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557 Publications avant 2019
Molecular and Cellular Endocrinology, 475, pp. 92-106.
Antignac, J.P., Applanat, M., Appenzeller, B.M.R., Beaudouin, R., Belzunces, L.P., Canivenc-lavier, M.C., Chevalier, A., Chevrier, C., Cravedi, J.P., Elefant, E., Emond, C., Eustache, F., Habert, R., Kolf-clauw, M., Le magueresse-battistoni, B., Mhaouty-kodja, S., Minier, C., Multignier, L., Schroeder, H., Thonneau, P., Pviguie, C., Pouzaud, F., Thierry-mieg, M., Burga, K., Verines-join, L., Fiore, K., Beausoleil, C., Michel, C., Rousselle, C., Pasquier, E.
The extensive database on BPA provides strong evidence of its adverse effects on reproductive, neurobehavioural, metabolic functions and mammary gland. Disruption of estrogenic pathway is central in the mediation of these effects although other modes of action may be involved. BPA has a weak affinity for ERα/β but interaction with extranuclearly located pathways activated by estrogens such as ERRγ and GPER reveals how BPA can act at low doses.
The effects are observed later in life after developmental exposure and are associated with pathologies of major societal concern in terms of severity, incidence, impact on quality of life, burden on public health system. The complexity of the dose response raise uncertainties on the possibility to establish safe levels and the scope of ED-mediated effects of BPA may be wider. These concerns fulfill the requirements for ED identification under REACH regulation.
Molecular and Cellular Endocrinology, 475, pp. 4-9.
Beausoleil, C., Emond, C., Cravedi, J.P., Antignac, J.P., Applanat, M., Appenzeller, B.M.R., Beaudouin, R., Belzunces, L.P., Canivenc, M.C., Chevalier, A., Chevrier, C., Elefant, E., Eustache, F., Habert, R., Kolf-clauw, M., Le magueresse-battistoni, B., Mhaouty-kodja, S., Minier, C., Multignier, L., Schroeder, H., Thonneau, P., Viguie, C., Pouzaud, F., Ormsby, J.N., Rousselle, C., Verines-jouin, L., Pasquier, E., Michel, C.
BPA is one of the most investigated substances for its endocrine disruptor (ED) properties and it is at the same time in the center of many ED-related controversies. The analysis on how BPA fits to the regulatory identification as an ED is a challenge in terms of methodology. It is also a great opportunity to test the regulatory framework with a uniquely data-rich substance and learn valuable lessons for future cases. From this extensive database, it was considered important to engage in a detailed analysis so as to provide specific and strong evidences of ED while reflecting accurately the complexity of the response as well the multiplicity of adverse effects. An appropriate delineation of the scope of the analysis was therefore critical. Four effects namely, alterations of estrous cyclicity, mammary gland development, brain development and memory function, and metabolism, were considered to provide solid evidence of ED-mediated effects of BPA.
Journal of Nuclear Cardiology, https://doi.org/10.1007/s12350-018-1404-7
Clément, A., Boutley, H., Poussier, S., Pierson, J., Lhuillier, M., Kolodziej, A., Olivier, J.-L., Karcher, G., Marie, P.-Y., Maskali, F.
Molecular and Cellular Endocrinology, 475, pp. 54-73.
Mhaouty-Kodja, S., Belzunces, L.P., Canivenc, M.C., Schroeder, H., Chevrier, C., Pasquier, E.
Many rodent studies and a few non-human primate data report impairments of spatial and non-spatial memory induced by exposure to bisphenol A (BPA), which are associated with neural modifications, particularly in processes involved in synaptic plasticity. BPA-induced alterations involve disruption of the estrogenic pathway as established by reversal of BPA-induced effects with estrogenic receptor antagonist or by interference of BPA with administered estradiol in ovariectomized animals. Sex differences in hormonal impregnation during critical periods of development and their influence on maturation of learning and memory processes may explain the sexual dimorphism observed in BPA-induced effects in some studies. Altogether, these data highly support the plausibility that alteration of learning and memory and synaptic plasticity by BPA is essentially mediated by disturbance of the estrogenic pathways. As memory function in humans involves similar signaling pathways, this mode of action of BPA has the potential to alter human cognitive abilities.
Oilseeds and fats, Crops and Lipids, 25 (4), pp. D406-D413.
Pinchaud, K., Maguin Gaté, K., Olivier, J.-L.
L’acide arachidonique alimentaire : un acteur à deux faces dans le cerveau et la maladie d’Alzheimer ? L’acide arachidonique est le second acide gras polyinsaturé cérébral et le premier de la série des ω-6. Les apports alimentaires d’acide arachidonique varient entre 50 et 300 mg/jour dans les régimes occidentaux mais pourraient être sous-estimés. Les triglycérides de la partie grasse des viandes fourniraient des quantités similaires aux phospholipides de la partie maigre. La maladie d’Alzheimer est une maladie neurodégénérative associée à l’âge et un problème de santé publique majeur dans le monde. Les oligomères de peptides β amyloïde en sont désormais reconnus comme l’agent principal, bien que la présence de la protéine tau est nécessaire à leur action. Avec d’autres auteurs, nous avons établi que la phospholipase A2 cytosolique, spécifique de l’acide arachidonique, assure les effets neurotoxiques des oligomères de peptide β amyloïde. Nous avons ensuite montré qu’un régime riche en acide arachidonique augmente la sensibilité des souris aux effets de ces oligomères, sans augmentation majeure de ses niveaux cérébraux. Ceci suggère que cet acide gras peut agir sur le cerveau par des effets périphériques comme une sub-inflammation dont le rôle dans la relation intestin-cerveau est discutée dans la littérature. Les apports alimentaires d’acide arachidonique devrait être intégrés dans la prévention de la maladie d’Alzheimer.
Arachidonic acid is the second polyunsaturated fatty acid in brain and the first one belonging to the ω-6 series. Dietary intakes of arachidonic are between 50 and 300 mg/day in western diets but they might be underestimated. Triglycerides from fat would provide similar amounts than phospholipids of lean meat. Alzheimer’s disease is an age-associated degenerative disease and a critical health concern worldwide. Amyloid-β peptide oligomers are presently recognized as the main and earliest agents of Alzheimer’s disease although their neurotoxicity requires the presence of tau protein. We and others established that the arachidonic-specific cytosolic phospholipase A2 is critical for the amyloid-β peptide oligomer neurotoxicity. Then, we showed that an arachidonic acid-rich diet increases the mouse sensitivity to the amyloid-β peptide oligomer deleterious effect without major increase of arachidonic acid levels in brain. This suggests that dietary arachidonic acid can exert its effects in brain through peripheral modifications. Involvement of systemic sub-inflammation and gut-brain communications are discussed based on the recent literature. The various data suggest that dietary arachidonic acid should be taken into account in the design of preventive strategies against Alzheimer’s disease.
Archives of Toxicology, 91 (8), pp. 2813-2825.
Appenzeller, B.M.R., Hardy, E.M., Grova, N., Chata, C., Fays, F., Briand, O., Schroeder, H., Duca, R.C.
Urine and plasma have been used to date for the biomonitoring of exposure to pollutants and are still the preferred fluids for this purpose; however, these fluids mainly provide information on the short term and may present a high level of variability regarding pesticide concentrations, especially for nonpersistent compounds. Hair analysis may provide information about chronic exposure that is averaged over several months; therefore, this method has been proposed as an alternative to solely relying on these fluids. Although the possibility of detecting pesticides in hair has been demonstrated over the past few years, the unknown linkage between exposure and pesticides concentration in hair has limited the recognition of this matrix as a relevant tool for assessing human exposure. Based on a rat model in which there was controlled exposure to a mixture of pesticides composed of lindane, β-hexachlorocyclohexane, β-endosulfan, p,p′-DDT, p,p′-DDE, dieldrin, pentachlorophenol, diazinon, chlorpyrifos, cyhalothrin, permethrin, cypermethrin, propiconazole, fipronil, oxadiazon, diflufenican, trifluralin, carbofuran, and propoxur, the current work demonstrates the association between exposure intensity and resulting pesticide concentration in hair. We also compared the results obtained from a hair analysis to urine and plasma collected from the same rats. Hair, blood, and urine were collected from rats submitted to 90-day exposure by gavage to the aforementioned mixture of common pesticides at different levels. We observed a linear relationship between exposure intensity and the concentration of pesticides in the rats’ hair (R Pearson 0.453–0.978, p < 0.01). A comparison with results from urine and plasma samples demonstrated the relevance of hair analysis and, for many chemicals, its superiority over using fluids for differentiating animals from different groups and for re-attributing animals to their correct groups of exposure based on pesticide concentrations in the matrix. Therefore, this study strongly supports hair analysis as a reliable tool to be used during epidemiological studies to investigate exposure-associated adverse health effects.
Journal of Functional Foods, 38 (A), pp. 464-473.
Benoit, S., Chaumontet, C., Schwarz, J., Cakir-Kiefer, C., Tomé, T., Miclo, L.
α-Casozepine, a bioactive peptide from milk casein, displays an anxiolytic-like activity in many species. Since its mode of action is still not elucidated, a study was conducted in Swiss mice to investigate c-Fos expression, a marker of neuronal activity, in different brain areas. After an intraperitoneal injection of α-casozepine (1 mg/kg), animals were placed either in a non-stressful or in an anxiety-inducing situation triggered with a light/dark box. No effect of α-casozepine on c-Fos expression was observed in the non-stressful situation. In the stressful situation, modulation of neuronal activity by α-casozepine was observed in different brain regions compared to that of vehicle. However, while diazepam, a benzodiazepine, modulated neuronal activity the same way in hippocampus, accumbens nucleus and hypothalamus, differences were observed in c-Fos expression in amygdala and prefrontal cortex compared to α-casozepine. These results strengthen the assumption that the anxiolytic mechanisms of α-casozepine differ partly of those of diazepam.
Journal of Alzheimer's Disease, 57 (2), pp. 437-445.
Gervaise-Henry, C., Watfa, G., Albuisson, E., Kolodziej, A., Dousset, B., Olivier, J.-L., Rivasseau Jonveaux, T., Malaplate-Armand, C.
Plos One, 17 (7), e0178668.
Guillot, X., Martin, H., Seguin-Py, S., Maguin-Gaté, K., Moretto, J., Totoson, P., Wendling, D., Demougeot, C., Tordi, N.
Objectives: Local cryotherapy is widely and empirically used in the adjuvant setting in rheumatoid arthritis treatment, however its own therapeutic and anti-inflammatory effects are poorly characterized. We aimed to evaluate the effects of local cryotherapy on local and systemic inflammation in Adjuvant-induced arthritis, a murine model of rheumatoid arthritis.
Methods: The effects of mild hypothermia (30°C for 2 hours) on cytokine protein levels (Multiplex/ELISA) were evaluated in vitro in cultured rat adjuvant-induced arthritis patellae. In vivo, local cryotherapy was applied twice a day for 14 days in arthritic rats (ice: n = 10, cold gas: n = 9, non-treated: n = 10). At day 24 after the induction of arthritis, cytokine expression levels were measured in grinded hind paws (Q-RT-PCR) and in the plasma (Multiplex/ELISA).
Results: In vitro, punctual mild hypothermia down-regulated IL-6 protein expression. In vivo, ice showed a better efficacy profile on the arthritis score and joint swelling and was better tolerated, while cold gas induced a biphasic response profile with initial, transient arthritis worsening. Local cryotherapy also exerted local and systemic anti-inflammatory effects, both at the gene and the protein levels: IL-6, IL-17A and IL-1β gene expression levels were significantly down-regulated in hind paws. Both techniques decreased plasma IL-17A while ice decreased plasma IL-6 protein levels. By contrast, we observed no effect on local/systemic TNF-α pathway.
Conclusions: We demonstrated for the first time that sub-chronically applied local cryotherapy (ice and cold gas) is an effective and well-tolerated treatment in adjuvant-induced arthritis. Furthermore, we provided novel insights into the cytokine pathways involved in Local cryotherapy's local and systemic anti-inflammatory effects, which were mainly IL-6/IL-17A-driven and TNF-α independent in this model.
Current Drug Targets, 18 (11), pp. 1269-1280.
Niaz, T., Hafeez, Z., Imran, M.
Background: Global death rate due to cardiovascular diseases (CVDs) is highest as compared to other ailments. Principal risk factor associated with CVDs is hypertension. Major classes of current antihypertensive (AHT) therapies include angiotensin converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARBs) and calcium channel blockers (CCBs). All these antihypertensive therapeutic drugs have low oral bioavailability and can induce upper respiratory tract abstraction, angioedema, reflex tachycardia and extreme hypotensive effect after oral administration which can cause lethal effects in patients with heart diseases.
Objective: Controlled and targeted release by using antihypertensive nano-medicines can provide better solution to overcome above-mentioned side effects.
Results: Scientific evolution towards the development of biopolymer based nano-carrier systems has unlocked new horizons for safe and/or edible nano drug delivery systems. In this article, we have reviewed in detail various mechanisms of AHT drugs, major draw backs associated with current therapeutic strategies, and the advantages of AHT nano-medicines over conventional drugs. Furthermore, recent reports of bio-based nano/micro -carrier systems with different AHT drugs have been analyzed with their key features. In depth review has been presented for chitosan as a potential carrier of AHT drugs due to its distinctive properties comprising muco-adhesive attribute, permeation enhancement as well as its biocompatible and biodegradable nature.
Conclusion: Chitosan based novel AHT nano-ceuticals can improve oral bioavailability, reduce hydrophobicity and increase the plasma half-life of AHT drugs by their sustained release in lower part of the GIT.
Brain, Behavior, and Immunity, 63, pp. 137-147.
Soualeh, N., Dridi, I., Eppe, G., Nemos, C., Soulimani, R., Bouayed, J.
Several lines of evidence indicate that early-life inflammation may predispose to mental illness, including depression, in later-life. We investigated the impact of perinatal exposure to polluted eels on neonatal, postnatal, and adult brain inflammation, and on the resignation behavior of male and female adult offspring mice. The effects of maternal standard diet (laboratory food) were compared to the same diet enriched with low, intermediate, or highly polluted eels. Brain inflammatory markers including cytokines were assessed in offspring mice on the day of birth (i.e., on the postnatal day–PND 1), upon weaning (PND 21) and at adulthood (PND 100). Plasma myeloperoxidase and corticosterone levels were evaluated at PND 100. Immobility behavior of offspring was assessed in adulthood (i.e., at PNDs 95–100), using the tail suspension and forced swimming tests. Chronic brain inflammation was found in male and female offspring mice compared to controls, as assessed at PNDs 1, 21, and 100. The level of myeloperoxidase was found to be significantly higher in both adult males and females vs. control offspring. However, high corticosterone levels were only found in male offspring mice that were perinatally exposed to eels, suggesting a gender-selective dysregulation of the adult hypothalamic-pituitaryadrenal (HPA) axis. Gender-specific differences were also detected in adulthood in regard to offspring resignation behavior. Thus, compared to controls, males, but not females, whose mothers were fed eels during pregnancy and lactation exhibited a depressive-like behavior in adult age in both behavioral models of depression. Depressive symptoms were more pronounced in male mice perinatally exposed to either intermediate or highly polluted eels than those exposed to only lowly polluted eels. Our results indicate that early-life inflammatory insult is a plausible causative factor that induces the depressive phenotype exhibited by male adult offspring mice, most likely through a gender-specific HPA axis enhanced activation.
Alzheimer's Research & Therapy, 9 (1), p. 69 : doi: 10.1186/s13195-017-0295-1
Thomas, M.H., Paris, C., Magnien, M., Colin, J., Pelleïeux, S., Coste, F., Escanyé, M.-C., Pillot, T., Olivier, J.-L.
Polyunsaturated fatty acids play a crucial role in neuronal function, and the modification of these compounds in the brain could have an impact on neurodegenerative diseases such as Alzheimer's disease. Despite the fact that arachidonic acid is the second foremost polyunsaturated fatty acid besides docosahexaenoic acid, its role and the regulation of its transfer and mobilization in the brain are poorly known.
Two groups of 39 adult male BALB/c mice were fed with an arachidonic acid-enriched diet or an oleic acid-enriched diet, respectively, for 12 weeks. After 10 weeks on the diet, mice received intracerebroventricular injections of either NaCl solution or amyloid-β peptide (Aβ) oligomers. Y-maze and Morris water maze tests were used to evaluate short- and long-term memory. At 12 weeks on the diet, mice were killed, and blood, liver, and brain samples were collected for lipid and protein analyses.
We found that the administration of an arachidonic acid-enriched diet for 12 weeks induced short-term memory impairment and increased deleterious effects of Aβ oligomers on learning abilities. These cognitive alterations were associated with modifications of expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, postsynaptic density protein 95, and glial fibrillary acidic protein in mouse cortex or hippocampus by the arachidonic acid-enriched diet and Aβ oligomer administration. This diet also led to an imbalance between the main ω-6 fatty acids and the ω-3 fatty acids in favor of the first one in erythrocytes and the liver as well as in the hippocampal and cortical brain structures. In the cortex, the dietary arachidonic acid also induced an increase of arachidonic acid-containing phospholipid species in phosphatidylserine class, whereas intracerebroventricular injections modified several arachidonic acid- and docosahexaenoic acid-containing species in the four phospholipid classes. Finally, we observed that dietary arachidonic acid decreased the expression of the neuronal form of acyl-coenzyme A synthetase 4 in the hippocampus and increased the cytosolic phospholipase A2 activation level in the cortices of the mice.
Dietary arachidonic acid could amplify Aβ oligomer neurotoxicity. Its consumption could constitute a risk factor for Alzheimer's disease in humans and should be taken into account in future preventive strategies. Its deleterious effect on cognitive capacity could be linked to the balance between arachidonic acid-mobilizing enzymes.
Journal of Functional Foods, 37, pp. 74-89.
Uriot, O., Denis, S., Junjua, M., Roussel, Y., Dary, A., Blanquet-Diot, S.
Probiotics are defined as live microorganisms that when administered in adequate amount confer a health benefit to the host. To be considered as a probiotic, a bacterial strain must not only be safe but should also survive in the human gastrointestinal tract and exert health benefits on its host. Streptococcus thermophilus is a Gram positive bacterium widely used in dairy fermentations for the production of yogurt and cheese. In contrast with other lactic acid bacteria, the probiotic status of S. thermophilus remains still questioned. This review gives an update of the human trials, in vivo assays in animal models and in vitro experiments, which have assessed the resistance of S. thermophilus to gastrointestinal stresses and have investigated its positive health effects. The underlying mechanisms of action are also described and the probiotic status of the bacterium is debated with respect to the available literature.
Clinical and experimental immunology, 188 (2), pp. 208-218.
Verhoeven, F., Totoson, P., Maguin-Gaté, K., Prigent-Tessier, A., Marie, C., Wendling, D., Moretto, J., Prati, C., Demougeot, C.
To determine the effect of glucocorticoids (GCs) on endothelial dysfunction (ED) and on traditional cardiovascular (CV) risk factors in the adjuvant-induced arthritis (AIA) rat model. At the first signs of AIA, a high dose (HD) [10 mg/kg/day, intraperitoneally (i.p.), GC-HD] or low dose (LD) (1 mg/kg/day, i.p., GC-LD) of prednisolone was administered for 3 weeks. Endothelial function was studied in aortic rings relaxed with acetylcholine (Ach) with or without inhibitors of nitric oxide synthase (NOS), cyclooxygenase 2 (COX-2), arginase, endothelium derived hyperpolarizing factor (EDHF) and superoxide anions (?O–2°) production. Aortic expression of endothelial NOS (eNOS), Ser1177-phospho-eNOS, COX-2, arginase-2, p22phox and p47phox was evaluated by Western blotting analysis. Arthritis scores, blood pressure, heart rate and blood levels of cytokines, triglycerides, cholesterol and glucose were measured. GC-HD but not GC-LD reduced arthritis score significantly and improved Ach-induced relaxation (P < 0·05). The positive effect of GC-HD resulted from increased NOS activity and EDHF production and decreased COX-2/arginase activities and O–2° production. These functional effects relied upon increased phospho-eNOS expression and decreased COX-2, arginase-2 and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression. Despite the lack of effect of GC-LD on ED, it increased NOS and EDHF and down-regulated O–2° pathways but did not change arginase and COX-2 pathways. GC-HD increased triglycerides levels and blood pressure significantly (P < 0·05). Both doses of GCs decreased to the same extent as plasma interleukin (IL)-1β and tumour necrosis factor (TNF)-α levels (P < 0·05). Our data demonstrated that subchronic treatment with prednisolone improved endothelial function in AIA via pleiotropic effects on endothelial pathways. These effects occurred independently of the deleterious cardiometabolic effects and the impact of prednisolone on systemic inflammation.
Toxicology Letters, 245, pp. 7-14.
Ardzivian Elnar, A., Desor, F., Legay, S., Nemos, C., Yen, F.T., Oster, T., Bohn, T., Soulimani, R.
The developing central nervous system is particularly vulnerable to environmental contaminants such as non-dioxin-like polychlorinated biphenyls (NDL-PCBs). This study investigated the potential oxidative effects in mice pups exposed via lactation to the sum of the six indicator NDL-PCBs (∑6 NDL-PCBs) at 0, 1, 10 and 100 ng/kg per 14 days, constituting levels below the guidance values fixed by French food safety agencies for humans at 10 ng/kg body weight per day. For this purpose, the oxidative status was assessed by flow cytometry via dichloro-dihydro-fluorescein diacetate in the cerebellum of juvenile male offspring mice during brain growth spurt [postnatal day (PND) 14]. No significant differences were found in the levels of reactive oxygen species in the cerebellar neurons or glial cells (astrocytes, oligodendrocytes and microglia) of lactationally exposed male mice at PND 14 (p>0.05). Concordantly, oxidative-stress related gene expression was measured by qPCR for catalase, copper zinc superoxide dismutase 1, glyoxalase 1, glutathione peroxidase 1, and glutathione reductase 1, in the cerebellum at PND 14 appeared unaffected, as also verified at the protein level by immunoblots. Moreover, transcriptomic data from our previous work have not shown differences in the mRNA expressions of genes belonging to GO terms involved in oxidative stress in neurons of male mice exposed to ∑6 NDL-PCBs compared to controls; except for glyoxalase 1 which was downregulated in neurons isolated from exposed group compared to controls. Our findings suggest that lactational exposure to NDL-PCBs at environmental relevant concentrations may not cause significant oxidative effect on juvenile cerebellum.
International Dairy Journal, 56, pp. 159-168.
El Hatmi, H., Jrad, Z., Khorchani, T., Jardin, J., Poirson, C., Perrin, C., Cakir-Kiefer, C., Girardet, J.-M.
Camel milk was fermented by Streptococcus thermophilus LMD-9 strain, the proteolytic system of which yielded peptides from the milk proteins. The peptides were isolated by cation-exchange chromatography and ultrafiltration, and then separated into 9 fractions by reversed-phase high-performance liquid chromatography. Two fractions displayed efficient radical-scavenging properties shown by Trolox equivalent antioxidant capacity assay. At least 347 peptides distributed in the different fractions were identified by tandem mass spectrometry. They mainly derived from the four different caseins, glycosylation-dependent cell adhesion molecule-1 (GlyCAM-1), also called lactophorin, and peptidoglycan recognition protein-1. For the first time, cleavage sites were identified for these six proteins and the susceptibility of GlyCAM-1 towards bacterial proteolysis directly in milk was shown. Investigation of peptide sequences homologous to known bioactive peptides highlighted not less than 16 different putative biological activities. Fermentation of camel milk was thus a means of food processing to produce potential bioactive peptides.
Dairy Science and Technology, 96, pp. 623-636.
Galia, W., Jameh, N., Perrin, C., Genay, M., Dary, A.
The acquisition of prtS by Streptococcus thermophilus strains allowed hydrolysis
of caseins into peptides and then to increase their growth in milk. This leads to faster
milk acidification, which is important in dairy industry. However, some strains harboring
the same allele of prtS present different acidification rates, which could be explained by a
difference in the regulation of prtS expression.We chose two strains with the same allele
of prtS (including the same promoter region): one, PB302, is with high acidification rate
while the other, PB18O, is without. They exhibited similar growth in M17, but not in
milk, where PB302 showed better growth. The expression of prtS and activity of PrtS
were lower in PB18O, in the two media tested.We demonstrated that other genes known
to be involved in carbon and nitrogen metabolism were overexpressed in PB302.
Interestingly, these genes were overexpressed in milk compared to M17. Nearly all these
genes possessed a putative CodY-box in their promoter region. Taken together, difference
of gene expression detected in PB302 between milk (low-peptide medium) and
M17 (rich-peptide medium) and presence of a putative CodY-box is a feature of the
transcriptional pattern of CodY-regulated genes. Altogether, our results propose that
acquisition of prtS is not enough in certain strains to achieve rapid milk acidification.
High transcriptional level of dtpT, amiF, ilvC, ilvB, bcaT, livJ, ackA, codY, and prtS in fast
acidifying strain suggests that this transcriptional pattern could be required for fast milk
acidification in Streptococcus thermophilus.
Food Chemistry, 209, pp. 114-122.
Guerin, J., Kriznik, A., Ramalanjaona, N., Le Roux, Y., Girardet, J.-M.
Bile salts act as steroidal detergents in the gut, which could also interact with peptides and improve their bioavailability, but according to an unclear mechanism. The occurrence of direct interaction between milk bioactive peptides, Ile-Asn-Tyr-Trp, Leu-Asp-Gln-Trp, and Leu-Gln-Lys-Trp, and different bile salts in submicellar or micellar state was investigated by intrinsic fluorescence measurement and dynamic light scattering, above the critical micellar concentration, the latter being determined by isothermal titration calorimetry. The peptides form aggregates, spontaneously. In the presence of bile salts, some released peptide monomers were bound at the micellar surface. The lack of hydrogen bond involving the C12-OH group of the steroid skeleton and the acidic function of some bile salts might promote the interaction with the peptides, as well as the lack of the C12-OH group rather than that of the C7-OH group. At submicellar concentrations, sodium taurochenodeoxycholate and taurodeoxycholate readily interacted with the most hydrophobic peptide Ile-Asn-Tyr-Trp.
Food Research International, 86, pp. 34-45.
Jameh, N., Galia, W., Awussi, A. A., Roux, É., Genay, M., Perrin, C., Dary, A.
In silico analysis of the genome of Streptococcus thermophilus LMD-9 revealed that this strain has a potential new peptide/nickel ABC transporter. We named this system OTS for Oligopeptide Transporter of S. thermophilus. It is composed of a peptide/nickel binding protein OtsA, two permeases OtsB and OtsC and a double ATPase OtsD. This system was presumably acquired by horizontal transfer from Actinobacteria or distant species like Lactococcus raffinolactis or Enterococcus asini may be via an intermediate like Lactococcus lactis or its ancestor. RT-PCR experiments proved that OTS gene cluster is transcribed and that at least the otsB, otsC, and otsD genes constitute an operon. A mutant LMD-9?ots, partially deleted for the otsA and otsB genes was constructed. Growth of LMD-9 and LMD-9?ots strains was monitored in the presence of different nitrogen sources and in the presence of urea and nickel. Results revealed that OTS is not implicated in nickel transport, but constitutes a new characterized transporter of peptides of small size, possibly di- and tripeptides in S. thermophilus.
LWT - Food Science and Technology, 70 (1), pp. 78-87.
Junjua, M., Kechaou, N., Chain, F., Awussi, A. A., Roussel, Y., Perrin, C., Roux, É., Langella, P., Bermúdez-Humarán, L.G., Le Roux, Y., Chatel, J.-M., Dary, A.
In spite of its contribution to health benefits of yogurt, probiotic properties of Streptococcus thermophilus remain less explored. Hence, we evaluated the capacities of 30 strains of different origins, to resist the stresses prevailing in digestive tracts, of adhering to the mucus producing HT29-MTX cells, as well as their anti-inflammatory properties. First, on the basis of results obtained by multilocus sequence typing, two very closely related groups were distinguished phylogenetically. However, it appeared that in spite of this phylogenetic proximity, resistance to low pH, bile salts and H2O2 and their capacities of adhesion highly varied from one strain to another. Furthermore, most of the strains reduced the production of the pro-inflammatory interleukin IL-8 after co-incubation with HT-29 cells, while they induced production of the anti-inflammatory interleukin IL-10, when incubated with Peripheral Blood Mononuclear Cells. On the basis of ratio of synthesis of IL-10 and of IL-12, currently used to evaluate the anti-inflammatory potential of a probiotic bacterium, three strains appeared to display a strong and promising in vitro anti-inflammatory potential, suggesting that they could be appropriate for elaborating anti-inflammatory functional fermented foods. Finally, the Principal Component Analysis method enabled us to cluster strains into 6 classes displaying distinct phenotypic properties.
Applied Microbiology and Biotechnology, 100 (8), pp. 3667-3679.
Kebouchi, M., Galia, W., Genay, M., Soligot-Hognon, C., Lecomte, X., Awussi, A. A., Perrin, C., Roux, É., Dary, A., Le Roux, Y.
Streptococcus thermophilus (ST) is a lactic acid
bacterium widely used in dairy industry and displays several
properties which could be beneficial for host. The objective of
this study was to investigate, in vitro, the implication of
sortase A (SrtA) and sortase-dependent proteins (SDPs) in
the adhesion of ST LMD-9 strain to intestinal epithelial cells
(IECs) and resistance to bile salt mixture (BSM;
taurocholoate, deoxycholate, and cholate). The effect of mutations
in prtS (protease), mucBP (MUCin-Binding Protein),
and srtA genes in ST LMD-9 in these mechanisms were examined.
The HT29-MTX, HT29-CL.16E, and Caco-2 TC7
cell lines were used. HT29-MTX and HT29-CL.16E cells
express different mucins found in the gastro intestinal tract;
whereas, Caco-2 TC7 express cell surface proteins found in
the small intestine. All mutants showed different adhesion
profiles depending on cell lines. The mutation in genes srtA
and mucBP leads to a significant decrease in LMD-9 adhesion
capacity to Caco-2 TC7 cells. A mutation in mucBP gene has
also shown a significant decrease inLMD-9 adhesion capacity
to HT29-CL.16E cells. However, no difference was observed
using HT29-MTX cells. Furthermore, ST LMD-9 and srtA
mutant were resistant to BSM up to 3 mM. Contrariwise, no
viable bacteria were detected for prtS and mucBP mutants at
this concentration. Two conclusions could be drawn. First,
SDPs could be involved in the LMD-9 adhesion depending
on the cell lines indicating the importance of eukaryotic-cell
surface components in adherence. Second, SDPs could contribute
to resistance to bile salts probably by maintaining the
cell membrane integrity.
Food Microbiology, 53 (A), pp. 2-9.
Lecomte, X., Gagnaire, V., Lortal, S., Dary, A., Genay, M.
Streptococcus thermophilus is the second most used bacterium in dairy industry. It is daily consumed by millions of people through the worldwide consumption of yogurts, cheeses and fermented milks. S. thermophilus presents many features that make it a good candidate for the production of heterologous proteins. First, its ability to be naturally transformable allows obtaining swiftly and easily recombinant strains using various genetic tools available. Second, its Generally Recognised As Safe status and its ability to produce beneficial molecules or to liberate bioactive peptides from milk proteins open up the way for the development of new functional foods to maintain health and well-being of consumers. Finally, its ability to survive the intestinal passage and to be metabolically active in gastrointestinal tract allows considering S. thermophilus as a potential tool for delivering various biological molecules to the gastrointestinal tract. The aim of this review is therefore to take stock of various genetic tools which can be employed in S. thermophilus to produce heterologous proteins and to highlight the advantages and future trends of use of this bacterium as a heterologous expression host.
Small Ruminant Research, 137, pp. 91-98.
Mahmoudi, I., Moussa, O. B., Khaldi, T. E. M., Kebouchi, M., Soligot-Hognon, C., Le Roux, Y., Hassouna, M.
Tweenty probiotic lactic acid bacteria (LAB) strains from Tunisian camel raw milk were identified among a collection of 177 isolates. The selected strains were able to tolerate pH 2, pepsin, pancreatin and bile salts, as restrictive criteria for probiotic potential. LAB strains were identified using 16S rRNA gene sequencing. Fourteen isolates belonged to the species Lactobacillus fermentum and six to Lactobacillus plantarum. None of this LAB showed mucin degradation or hemolytic activity, while proving resistant to a series of clinically antibiotics. All strains have antibacterial activity against Listeria monocytogenes, Staphylococcus aureus and Escherchia coli. However, only 18 strains inhibited Salmonella thyphimirium. The L. fermentum strains showed an important level of adhesion to human Caco-2 and HT29-MTX epithelial cells. Our work suggests that camel raw milk is valuable source of probiotic bacteria with functional characters of intestinal lactobacilli. These bacteria may be further used in probiotic applications.
Neurotoxicology, 53, pp. 321-333.
Peiffer, J., Grova, N., Hidalgo, S., Salquèbre, G., Rychen, G., Bisson, J.-F., Appenzeller, B.M., Schroeder, H.
Journal of Neurology & Neuromedicine, 1 (9), pp. 1-6.
Thomas, M., Pelleieux, S., Vitale, N., Olivier, J.-L.
Alzheimer’s disease is a very complex disease in which neuroinflammation and synaptic dysfunctions play a critical role in association with the two well-known molecular agents of the disease, the Aβ1-42 peptide oligomers and the hyperphosphorylated tau protein. Arachidonic acid, the main member of the ω-6 series, is quantitatively the second polyunsaturated fatty acid in brain and is mainly esterified in membrane phospholipids. It is specifically released by the cytosolic phospholipase A2 whose inhibition or gene suppression counteract the deleterious effects of Aβ1-42 peptide oligomers on cognitive abilities. Arachidonic acid can be reincorporated under the action of the acyl-CoA synthetase-4 and lysophospholipid acyltransferases which remain to be characterized. Free arachidonic acid can be involved in Alzheimer’s disease through several mechanisms. First it is converted by cyclooxygenases-1/2 and the specific prostaglandin synthases into PGE2 and PGD2 which contributes to the occurrence and progression of neuroinflammation. Neuroinflammation has positive as well as negative effects, by favoring Aβ1-42 peptide clearance on one hand and by increasing the production of neurotoxic compounds on the other hand. Second, free arachidonic acid is also involved in synaptic functions as a retrograde messenger and as a regulator of neuromediator exocytosis. Third, some studies indicated that free arachidonic acid and its derivatives activate kinases involved in tau hyperphosphorylation. In addition, the dietary intakes of arachidonic acid in western food increased in the last period. Taken together, these various reports support the hypothesis that arachidonic acid is interesting target in nutrition-based preventive strategies against this disease.
Biochimie, S0300-9084 (16) 30145-6
Thomas, M., Pelleieux, S., Vitale, N., Olivier, J.-L.
Alzheimer's disease and associated diseases constitute a major public health concern worldwide. Nutrition-based, preventive strategies could possibly be effective in delaying the occurrence of these diseases and lower their prevalence. Arachidonic acid is the second major polyunsaturated fatty acid (PUFA) and several studies support its involvement in Alzheimer's disease. The objective of this review is to examine how dietary arachidonic acid contributes to Alzheimer's disease mechanisms and therefore to its prevention. First, we explore the sources of neuronal arachidonic acid that could potentially originate from either the conversion of linoleic acid, or from dietary sources and transfer across the blood-brain-barrier. In a second part, a brief overview of the role of the two main agents of Alzheimer's disease, tau protein and Aβ peptide is given, followed by the examination of the relationship between arachidonic acid and the disease. Third, the putative mechanisms by which arachidonic acid could influence Alzheimer's disease occurrence and evolution are presented. The conclusion is devoted to what remains to be determined before integrating arachidonic acid in the design of preventive strategies against Alzheimer's disease and other neurodegenerative diseases.
Plos One, 11 (1), e0146744.
Totoson, P., Maguin-Gaté, K., Nappey, M., Wendling, D., Demougeot, C.
Objectives: To determine mechanisms involved in endothelial dysfunction (ED) during the course of arthritis and to investigate the link between cytokines, chemokines and osteoprotegerin.
Approach and results: Experiments were conducted on aortic rings at day 4 (preclinical), day 11 (onset of disease), day 33 (acute disease) and day 90 (chronic disease) after adjuvant-induced arthritis (AIA) in Lewis rats. At day 4, the unique vascular abnormality was a reduced norepinephrine-induced constriction. At day 11, endothelial function assessed by the relaxation to acetylcholine was normal despite increased cyclo-oxygenase-2 activity (COX-2) and overproduction of superoxide anions that was compensated by increased nitric oxide synthase (NOS) activity. At day 33, ED apparition coincides with the normalization of NOS activity. At day 90, ED was only observed in rats with a persisting imbalance between endothelial NOS and COX-2 pathways and higher plasma levels of IL-1β and TNFα. Plasma levels of IL-1β, TNFα and MIP-1α negatively correlated with Ach-induced relaxation throughout the course of AIA.
Conclusions: Our data identified increased endothelial NOS activity as an important compensatory response that opposes the ED in the early arthritis. Thereafter, a cross-talk between endothelial COX-2/NOS pathways appears as an important element for the occurrence of ED. Our results encourage determining the clinical value of IL-1β, TNFα and MIP-1α as biomarkers of ED in RA.
Rheumatology (Oxford), 55 (7), pp. 1308-1317.
Totoson, P., Maguin-Gaté, K., Prigent-tessier, A., Monnier, A., Verhoeven, F., Marie, C., Wendling, D., Demougeot, C.
Objectives: To determine the effect of etanercept on endothelial dysfunction and on traditional cardiovascular (CV) risk factors in the adjuvant-induced arthritis (AIA) rat model.
Methods: At the first signs of arthritis, etanercept (10 mg/kg/3 days, s.c.) or saline was administered for 3 weeks in AIA rats. Body weights and arthritis scores were monitored daily. Endothelial function was studied in aortic rings relaxed with acetylcholine (Ach) with or without inhibitors of nitric oxide synthase (NOS), cyclo-oxygenase (COX-2), arginase, endothelium-derived hyperpolarizing factor and superoxide anions (O2 (-)°) production. Aortic expression of endothelial nitic oxide synthase (eNOS), Ser1177-phospho-eNOS, COX-2, arginase-2, p22(phox) and p47(phox) was evaluated by western blotting analysis. Blood pressure, heart rate and blood levels of triglycerides, cholesterol and glucose were measured.
Results: Etanercept significantly reduced arthritis score (P < 0.001). It improved Ach-induced relaxation (P < 0.05) as a result of increased NOS activity, decreased COX-2/arginase activities and decreased O2 (-)° production. These functional effects relied on increased eNOS expression and phosphorylation, and decreased COX-2, arginase-2 and p22(phox) expressions. No correlation was found between arthritis score and Ach-induced relaxation. The treatment did not change triglycerides, cholesterol and glucose levels, but significantly increased systolic blood pressure and heart rate (P < 0.05).
Conclusion: Our data demonstrated that efficient dosage of etanercept on inflammatory symptoms improved endothelial function in AIA. This beneficial effect on endothelial function is disconnected from its impact on CV risk factors and relates to pleiotropic effects of etanercept on endothelial pathways. These results suggest that etanercept could be a good choice for patients with rheumatoid arthritis at high risk of CV events.
Food Microbiology, 53 (A), pp. 18-29.
Uriot, O., Galia, W., Awussi, A. A., Perrin, C., Denis, S., Chalancon, S., Lorson, É., Poirson, C., Junjua, M., Le Roux, Y., Alric, M., Dary, A., Blanquet-Diot, S., Roussel, Y.
Streptococcus thermophilus, a lactic acid bacterium used to produce yogurts and cheeses is more and more considered for its potential probiotic properties. This implies that additional information should be obtained regarding its survival and metabolic activity in the human Gastro-Intestinal Tract (GIT). In this study, we screened 30 S. thermophilus strains for urease, small heat shock protein, and amino-acid decarboxylase functions which may play a role in survival in the upper part of the GIT. The survival kinetics of 4 strains was investigated using the TIM, a physiologically relevant in vitro dynamic gastric and small intestinal model. The three strains LMD9, PB18O and EBLST20 showed significantly higher survival than CNRZ21 in all digestive compartments of the TIM, which may be related to the presence of urease and heat shock protein functions. When LMD9 bacterial cells were delivered in a fermented milk formula, a significant improvement of survival in the TIM was observed compared to non-fermented milk. With the RIVET (Recombinase In Vivo Expression Technology) method applied to the LMD9 strain, a promoter located upstream of hisS, responsible for the histidyl-transfer RNA synthesis, was found to be specifically activated in the artificial stomach. The data generated on S. thermophilus survival and its adaptation capacities to the digestive tract are essential to establish a list of biomarkers useful for the selection of probiotic strains.
Arthritis research and therapy, 18 (1), pp. 258.
Verhoeven, F., Prati, C., Maguin-Gaté, K., Wendling, D., Demougeot, C.
Rheumatoid arthritis (RA) is the most common systemic autoimmune disease characterized by articular and extra-articular manifestations involving cardiovascular (CV) diseases. RA increases the CV mortality by up to 50 % compared with the global population and CV disease is the leading cause of death in patients with RA. There is growing evidence that RA favors accelerated atherogenesis secondary to endothelial dysfunction (ED) that occurs early in the course of the disease. ED is a functional and reversible alteration of endothelial cells, leading to a shift of the actions of the endothelium towards reduced vasodilation, proinflammatory state, proliferative and prothrombotic properties. The mechanistic links between RA and ED have not been fully explained, but growing evidence suggests a role for traditional CV factors, auto-antibodies, genetic factors, oxidative stress, inflammation and iatrogenic interventions such as glucocorticoids (GCs) use. GCs have been used in RA for several decades. Whilst their deleterious CV side effects were described in the 1950s, their effect on CV risk associated with inflammatory arthritis remains subject for debate. GC might induce negative effects on endothelial function, via a direct effect on endothelium or via increasing CV risk factors. Conversely, they might actually improve endothelial function by decreasing systemic and/or vascular inflammation. The present review summarizes the available data on the impact of GCs on endothelial function, both in normal and inflammatory conditions, with a special focus on RA patients.
Toxicology, 328, pp. 57-65.
Ardzivian, A., Desor, F., Marin F., Soulimani, R., Nemos, C.
Previously, we evaluated the effects of lactational exposure to a representative mixture of the six indicator non-dioxin-like polychlorinated biphenyls (∑6 NDL-PCBs) at low levels on the neurobiological changes and developmental/behavioral performances in mice. In this study, we analyzed the global gene expression profile in cerebellar neurons isolated from male mice presenting the most significant induction of anxiety-like behavior in our previous study (10 ng/kg ∑6 NDL-PCBs). Our results revealed changes in the expression of 16658 genes in the neurons of the exposed mice. Among these, 693 upregulated [fold change (FC) > 2; p < 0.05] and 665 downregulated (FC < 2; p < 0.05) genes were statistically linked to gene ontology terms (GO). Overexpressed genes belonged to GO terms involved with the cell cycle, DNA replication, cell cycle checkpoint, response to DNA damage stimulus, regulation of RNA biosynthetic processes, and microtubule cytoskeleton organization. Downregulated genes belonged to terms involved with the transmission of nerve impulses, projection neurons, synapse hands, cell junctions, and regulation of RNA biosynthetic processes. Using qPCR, we quantified gene expression related to DNA damage and validated the transcriptomic study, as a significant overexpression of Atm-Atr Bard1, Brca2, Fancd2, Figf, Mycn, p53 and Rad51 was observed between groups (p < 0.001). Finally, using immunoblots we determined the expression level of six selected proteins. We found that changes in the protein expression of Atm Brca1, p53, Kcnma1, Npy4r and Scn1a was significant between exposed and control groups (p < 0.05), indicating that the expression pattern of these proteins agreed with the expression pattern of their genes by qPCR, further validating our transcriptomic findings. In conclusion, our study showed that early life exposure of male mice to a low level of ∑6 NDL-PCBs induced p53-dependent responses to cellular stress and a decrease in the expression of proteins involved in the generation, conduction, and transmission of electrical signals in neurons.
Food Chemistry, 183, pp. 129-135.
Canabady-Rochelle, L.L.S., Harscoat-Schiavo, C., Kessler, V., Aymes, A., Fournier, F., Girardet, J.-M.
The purpose of this study was to improve two common tests used for antioxidant capacity measurements, i.e. the reducing power and chelating ability measurements, for appropriate comparisons between the molecules tested and chosen references, as the usual methods are often performed in a qualitative way rather than a quantitative way. After revision, it was then possible to determine an AERC indice (Ascorbate Equivalent Reducing Capacity) and a CECC (Carnosine Equivalent Chelating Capacity) or EECC (EDTA Equivalent Chelating Capacity) indice according to the standard chosen, by analogy to the TEAC indice (Trolox Equivalent Antioxidant Capacity) already used in many reported works to determine the free radical scavenging activity. Thus, the determination of these relative indices enables the comparison of antioxidative capacities obtained in various studies. The adaptation of these two tests to micro-scales and the calculation of AERC, EECC and CECC were performed on model peptides.
Transl Psychiatry., 5, e595.
Corlier, F., Rivals, I., Lagarde, J., Hamelin, L., Corne, H., Dauphinot, L., Ando, K., Cossec, J.-C., Fontaine, G., Dorothée, G., Malaplate-Armand, C., Olivier, J.-L., Dubois, B., Bottlaender, M., Duyckaerts, C., Sarazin, M., Potier, M.-C., ImaBio3
Identification of blood-based biomarkers of Alzheimer's disease (AD) remains a challenge. Neuropathological studies have identified enlarged endosomes in post-mortem brains as the earliest cellular change associated to AD. Here the presence of enlarged endosomes was investigated in peripheral blood mononuclear cells from 48 biologically defined AD patients (25 with mild cognitive impairment and 23 with dementia (AD-D)), and 23 age-matched healthy controls using immunocytochemistry and confocal microscopy. The volume and number of endosomes were not significantly different between AD and controls. However, the percentage of cells containing enlarged endosomes was significantly higher in the AD-D group as compared with controls. Furthermore, endosomal volumes significantly correlated to [C(11)]PiB cortical index measured by positron emission tomography in the AD group, independently of the APOE genotype, but not to the levels of amyloid-beta, tau and phosphorylated tau measured in the cerebrospinal fluid. Importantly, we confirmed the presence of enlarged endosomes in fibroblasts from six unrelated AD-D patients as compared with five cognitively normal controls. This study is the first, to our knowledge, to report morphological alterations of the endosomal compartment in peripheral cells from AD patients correlated to amyloid load that will now be evaluated as a possible biomarker.
Journal of Agricultural and Food Chemistry, 63 (34), pp. 7522-7531.
Hafeez, Z., Cakir-Kiefer, C., Girardet, J.-M., Lecomte, X., Paris, C., Galia, W., Dary, A., Miclo, L.
The influence on the hydrolysis of isracidin of cell-associated extracellular aminopeptidase and X-prolyl dipeptidyl peptidase activities in addition to protease PrtS of Streptococcus thermophilus strains was investigated. S. thermophilus LMD-9 (PrtS+ phenotype) efficiently hydrolyzed the isracidin mainly through the PrtS activity, whereas strain CNRZ1066 (PrtS- phenotype) and two mutant strains LMD-9-?prtS and LMD-9-?prtS-?htrA also displayed substrate hydrolysis, but different from that of the wild type strain LMD-9. Identification by mass spectrometry of breakdown products of isracidin revealed the existence of novel cell-associated extracellular carboxypeptidase and peptidyl dipeptidase activities in all PrtS- strains, besides known cell-associated extracellular aminopeptidase and X-prolyl dipeptidyl peptidase activities. Both aminopeptidase and peptidyl dipeptidase activities were not able to cleave the isracidin at peptide bonds with proline residues. No hydrolysis of isracidin was detected in cell free filtrate for all the strains studied, indicating that no cell lysis had occurred. Taken together, these results suggested the presence of cell-associated extracellular peptidase activities in S. thermophilus strains that could be vital for the growth of PrtS- strains.
International Dairy Journal, 49, pp. 78-88.
Matéos, A., Guyard-Nicodème, M., Baglinière, F., Jardin, J., Gaucheron, F., Dary, A., Humbert, G., Gaillard, J.-L.
UHT milk made from milk contaminated by Pseudomonas LBSA1 destabilised during storage. Sedimentation of UHT milk was observed; zeta potential of casein micelles decreased, while contents of noncasein nitrogen and non-protein nitrogen increased. Pseudomonas LBSA1 produced an extracellular
protease that hydrolysed caseins but not whey proteins; this was identified as AprX, a thermoresistant
protease belonging to the serralysin family. This protease showed a broad range of pH activity (pH 6 to
pH 10) and an optimal temperature of activity of 40°C. Peptides released from purified alpha-s1-, beta- and kappa-caseins were determined by tandem mass spectrometry. The identified cleavage sites did not reveal a strong specificity of the extracellular protease. However, the presence of basic or aromatic amino acid residues in the P1 position had a positive influence on cleavage in comparison with acidic amino acid residues or proline.
Neurotoxicology & Teratology, 52 (Part B), pp. 170-180.
Maurice, N., Olry, J.-C., Cariou, R., Dervilly-Pinel, G., Le Bizec, B., Travel, A., Jondreville, C., Schroeder, H.
J Alzheimers Dis, 45 (1), pp. 195-204.
Pincon, A., Thomas, M., Huguet, M., Allouche, A., Colin, J., Georges, A., Derrien, A., Lanhers, M.-C., Malaplate-Armand, C., Oster, T., Corbier, C., Pillot, T., Olivier, J.-L., Yen, F.T.
Alzheimer’s disease (AD) is a neurodegenerative disease that has been linked to changes in cholesterol metabolism. Neuronal cholesterol content significantly influences the pro-apoptotic effect of amyloid-beta peptide42 (Abeta42), which plays a key role in AD development. We previously reported that aged mice with reduced expression of the lipolysis stimulated lipoprotein receptor (LSR+/−), demonstrate membrane cholesterol accumulation and decreased intracellular lipid droplets in several brain regions, suggesting a potential role of LSR in brain cholesterol distribution.We questioned if these changes rendered the LSR+/− mouse more susceptible to Abeta42-induced cognitive and biochemical changes. Results revealed that intracerebroventricular injection of oligomeric Abeta42 in male 15-month old LSR+/+ and LSR+/− mice led to impairment in learning and long-term
memory and decreased cortical cholesterol content of both groups; these effects were significantly amplified in the Abeta42- injected LSR+/− group. Total latency of the Morris test was significantly and negatively correlated with cortical cholesterol content of the LSR+/− mice, but not of controls. Significantly lower cortical PSD95 and SNAP−25 levels were detected in Abeta42-injected LSR+/− mice as compared to Abeta42-injected LSR+/+ mice. In addition, 24S-hydroxy cholesterol metabolite levels were significantly higher in the cortex of LSR+/− mice. Taken together, these results suggest that changes in cortex cholesterol regulation as a result of the LSR+/− genotype were linked to increased susceptibility to amyloid stress, and we would therefore propose the aged LSR+/− mouse as a new model for understanding the link between modified cholesterol regulation as risk
factor for AD.
Food Chemistry, 187, pp. 305-313.
Zennia, S.S.A., Mati, A., Saulnier, F., Verdier, Y., Chiappetta, G., Mulliert, G., Miclo, L., Vinh, J., Girardet, J.-M.
Nonenzymatic deamidation of asparaginyl residues can occur spontaneously under physiological conditions principally when a glycyl residue is at the carboxyl side of Asn and leads to formation of aspartyl and isoaspartyl residues. This modification can change the biological activity of proteins or peptides and trigger an auto-immune response. The alpha-lactalbumins of members of the Camelidae family are the only of described alpha-lactalbumins that carry two AsnGly sequences. In the present study, high-resolution mass spectrometry, which enables accurate mass measurement has shown that Asn16 and Asn45 underwent a nonenzymatic deamidation, the sequence Asn45–Gly46 being deamidated spontaneously at nearneutral and basic pH and Asn16–Gly17 rather at basic pH. The 16–17 sequence was probably stabilized at near-neutral pH by hydrogen bonds according to the molecular modelisation performed with the camel protein.
PLOS One, 9 (1), pp. e87607-e87607.
Bunet, R., Riclea, R., Laureti, L., Hôtel, L., Paris, C., Girardet, J.-M., Spiteller, D., Dickschat, J.-S., Leblond, P., Aigle, B.
The phosphopantetheinyl transferases (PPTases) are responsible for the activation of the carrier protein domains of the polyketide synthases (PKS), non ribosomal peptide synthases (NRPS) and fatty acid synthases (FAS). The analysis of the Streptomyces ambofaciens ATCC23877 genome has revealed the presence of four putative PPTase encoding genes. One of these genes appears to be essential and is likely involved in fatty acid biosynthesis. Two other PPTase genes, samT0172 (alpN) and samL0372, are located within a type II PKS gene cluster responsible for the kinamycin production and an hybrid NRPS-PKS cluster involved in antimycin production, respectively, and their products were shown to be specifically involved in the biosynthesis of these secondary metabolites. Surprisingly, the fourth PPTase gene, which is not located within a secondary metabolite gene cluster, appears to play a pleiotropic role. Its product is likely involved in the activation of the acyl- and peptidyl-carrier protein domains within all the other PKS and NRPS complexes encoded by S. ambofaciens. Indeed, the deletion of this gene affects the production of the spiramycin and stambomycin macrolide antibiotics and of the grey spore pigment, all three being PKS-derived metabolites, as well as the production of the nonribosomally produced compounds, the hydroxamate siderophore coelichelin and the pyrrolamide antibiotic congocidine. In addition, this PPTase seems to act in concert with the product of samL0372 to activate the ACP and/or PCP domains of the antimycin biosynthesis cluster which is also responsible for the production of volatile lactones.
International Dairy Journal, 38 (2), pp. 104-115.
Chang, O.-K., Roux, É., Awussi, A. A., Miclo, L., Jardin, J., Jameh, N., Dary, A., Humbert, G., Perrin, C.
Bioactive peptides can be produced from milk proteins in fermented products by proteases of lactic acid
bacteria. The cell envelope protease (PrtS) of Streptococcus thermophilus is anchored at the cellwall, but we
recently discovered that the 4F44 strain produces a soluble form that can be recovered in medium supernatant.
This workwas aimed at optimising the production of bioactive peptides from bovine caseins. By
growing S. thermophilus 4F44 in the newly designed YLUNi medium, a high quantity of the soluble form of
PrtS could be produced that could be directly used as the proteolytic agent on sodium caseinate. Peptide
production was monitored by reverse phase-high performance liquid chromatography and tandem mass
spectrometry; of 247 peptides identified, 143 were derived from beta-casein. Twenty-two peptides, already
reported in the literature as bioactive, include ACE-inhibitory, antioxidant, immunomodulating, or antibacterial
peptides; addition of such peptides could improve the health benefits of dairy products.
Neurotoxicology, 43 (1), pp. 90-101.
Crepeaux, G., Grova, N., Bouillaud-Kremarik, P., Sikahyeva, N., Salquebre, G., Rychen, G., Soulimani, R., Appenzeller, B.M., Schroeder, H.
J. Chromatogr. A, 1364 (1), pp. 183-191.
Grova, N., Salquebre, G., Hardy, E., Schroeder, H., Appenzeller, B.M.
Food Research International, 63 (A), pp. 71-80.
Hafeez, Z., Cakir-Kiefer, C., Roux, É., Perrin, C., Miclo, L., Dary, A.
Besides their basic nutritional role, dietary proteins contain bioactive peptides which are encrypted in their sequence and may modulate different body functions such as digestive, cardiovascular, immune and nervous systems, and therefore contribute in maintaining consumer health. Currently, milk proteins are considered to be the major source of bioactive peptides. The occurrence of these peptides has already been reported in fermented milk products such as yogurt, sour milk or kefir and some of them have been shown to confer health benefits. This review focuses on different strategies that could be employed to enhance the production of bioactive peptides from the milk proteins that will be consequently used to functionalize the fermented milk products. Three types of strategies are developed. The first exploits the proteolytic system of lactic acid bacteria (LAB) or food grade enzymes or combination of both to release the functional peptides from the milk proteins directly in the fermented milk products. The second concerns the supplementation of the fermented milk products with the bioactive peptides obtained outside of the product through the hydrolysis of the purified proteins by the same enzyme sources. Finally, the last consists in the production of the bioactive peptides, initially identified from the milk-proteins, by microorganisms using recombinant DNA technology.
Dairy Science & Technology, 94 (3), pp. 205-224.
Jrad, Z., El Hatmi, H., Adt, I., Girardet, J.-M., Cakir-Kiefer, C., Jardin, J., Degraeve, P., Khorchani, T., Oulahal, N.
Camel milk and colostrum are known to be a rich source of bioactive proteins. Camel milk, colostrum and colostral whey proteins were successively hydrolysed by pepsin and pancreatin using an in vitro protocol mimicking gastro-intestinal digestion. The degradation of proteins was characterised by electrophoresis and reversed-phase ultra-high performance liquid chromatography. Two whey proteins, α-lactalbumin and immunoglobulins G, were more resistant to the digestive proteolytic enzymes than other camel milk and colostrum proteins. Undigested and digested samples were assayed for their antioxidant, angiotensin I-converting enzyme inhibitory and antimicrobial properties. Camel colostrum, colostral whey and milk proteins had unveiled angiotensin I-converting enzyme (ACE) inhibitory activity following in vitro enzymatic digestion and a higher free radical scavenging activity than before their digestion. Moreover, Escherichia coli XL1 blue and Listeria innocua LRGIA01 cells growth were both inhibited by undigested and digested samples, suggesting that antimicrobial proteins resisted to the action of digestive enzymes or that antimicrobial fragments of camel milk and colostrum proteins were released or both. After pepsin and pancreatin hydrolysis, camel milk and colostrum proteins digests still had an antibacterial activity and their antioxidative and ACE-inhibitory activity even increased, suggesting that bioactive fragments of camel milk and colostrum proteins such as antioxidative and ACE-inhibitory peptides were released. Among 181 peptides identified by tandem mass spectrometry, 25 were homologous to known bioactive peptides, particularly with ACE inhibitors and free radical scavengers.
Journal of Applied Microbiology, 116 (3), pp. 620-631.
Junjua, M., Galia, W., Gaci, N., Uriot, O., Genay, M., Bachmann, H., Kleerebezem, M., Dary, A., Roussel, Y.
Objectifs
Construire et valider l'outil R-IVET chez Streptococcus thermophilus (ST)
Matériel et méthodes et Résultats
Le système R-IVET que nous avons construit dans la souche LMD-9 comprend le plasmide pULNcreB qui permet la fusion transcriptionnelle avec le gène codant le recombinase site-spécifique Cre et la cassette chromosomique contenant un gène de résistance à la spectinomycine flanqué par 2 sites loxP. Sur milieu M17, les promoteurs des gènes codant la protéase PrtS, la protéine de choc thermique Hsp16 et l'opéron lactose ont conduit à la délétion de la cassette, indiquant une activité promotrice dans ces conditions. Le promoteur de l'opéron lactose était également activé durant le transit dans le tractus gastrointestinal d'une souris.
Conclusion
Le système R-IVET développé chez ST est relativement stable, fonctionnel, très sensible et peut être utilisé pour mesurer l'activité des promoteurs qui sont spécifiquement actifs in vivo.
Impact de l'étude
Cette première adaptation de l'outil R-IVET chez ST fournit un outil très précieux permettant une exploration de l'état physiologique de ST dans le TGI de mammifères, lors du processus de fermentation ou dans les produits laitiers.
To construct and validate the recombinase-based in vivo expression technology (R-IVET) tool in Streptococcus thermophilus (ST).
The R-IVET system we constructed in the LMD-9 strain includes the plasmid pULNcreB allowing transcriptional fusion with the gene of the site-specific recombinase Cre and the chromosomal cassette containing a spectinomycin resistance gene flanked by two loxP sites. When tested in M17 medium, promoters of the genes encoding the protease PrtS, the heat-shock protein Hsp16 and of the lactose operon triggered deletion of the cassette, indicating promoter activity in these conditions. The lactose operon promoter was also found to be activated during the transit in the murine gastrointestinal tract.
The R-IVET system developed in ST is relatively stable, functional, very sensitive and can be used to assay activity of promoters, which are specifically active in in vivo conditions.
This first adaptation of R-IVET to ST provides a highly valuable tool allowing an exploration of the physiological state of ST in the GIT of mammals, fermentation processes or dairy products.
Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics, 1844 (7), pp. 1317-1331
Kuhn, I., Kellenberger, E., Cakir-Kiefer, C., Muller-Steffner, H., Schuber, F.
Bovine CD38/NAD(+) glycohydrolase catalyzes the hydrolysis of NAD(+) to nicotinamide and ADP-ribose and the formation of cyclic ADP-ribose via a stepwise reaction mechanism. Our recent crystallographic study of its Michaelis complex and covalently-trapped intermediates provided insights into the modalities of substrate binding and the molecular mechanism of bCD38. The aim of the present work was to determine the precise role of key conserved active site residues (Trp118, Glu138, Asp147, Trp181 and Glu218) by focusing mainly on the cleavage of the nicotinamide-ribosyl bond. We analyzed the kinetic parameters of mutants of these residues which reside within the bCD38 subdomain in the vicinity of the scissile bond of bound NAD(+). To address the reaction mechanism we also performed chemical rescue experiments with neutral (methanol) and ionic (azide, formate) nucleophiles. The crucial role of Glu218, which orients the substrate for cleavage by interacting with the N-ribosyl 2'-OH group of NAD(+), was highlighted. This contribution to catalysis accounts for almost half of the reaction energy barrier. Other contributions can be ascribed notably to Glu138 and Asp147 via ground-state destabilization and desolvation in the vicinity of the scissile bond. Key interactions with Trp118 and Trp181 were also proven to stabilize the ribooxocarbenium ion-like transition state. Altogether we propose that, as an alternative to a covalent acylal reaction intermediate with Glu218, catalysis by bCD38 proceeds through the formation of a discrete and transient ribooxocarbenium intermediate which is stabilized within the active site mostly by electrostatic interactions.
Microbial Cell Factories, 13 (1), pp. 82-82.
Lecomte, X., Gagnaire, V., Briard-Bion, V., Jardin, J., Lortal, S., Dary, A., Genay, M.
CONTEXTE:
Des études fondamentales aux procédés industriels, la synthèse de protéines hétérologues par des micro-organismes est largement utilisée. La sécrétion de protéines hétérologues solubles dans le milieu extracellulaire facilite leur récupération, tandis que leur fixation à la surface de la cellule permet l'utilisation de cellules hôtes recombinantes comme supports de protéines ou de peptides. Un des points clés pour mener à bien l'expression hétérologue est de choisir l'hôte approprié. Nous proposons d'élargir le panel des hôtes de sécrétion hétérologues en utilisant Streptococcus thermophilus LMD-9. Cette bactérie lactique a un statut GRAS, est largement utilisée dans la fabrication de yaourts, laits fermentés et fromages, et est facilement transformable par compétence naturelle. Cette étude démontre la faisabilité de la sécrétion d'une protéine hétérologue ancrée à la surface de S. thermophilus. Pour cela, nous avons utilisé la cell envelope proteinase (CEP) PrtH de Lactobacillus helveticus CNRZ32 CIRM-BIA 103.
RÉSULTATS:
En utilisant S. thermophilus LMD-9 comme souche de base, trois souches recombinantes ont été construites: i) un contrôle négatif correspondant à S. thermophilus PrtS-mutant dans lequel le gène codant pour la CEP PrtS a été partiellement délété; ii) un mutant PrtH+ exprimant la pro-protéine PrtH de L. helveticus avec son propre motif d'attachement à la paroi cellulaire (de type S-layer) et iii) un mutant PrtH+WANS exprimant la pro-protéine PrtH avec le motif d'ancrage LPXTG de PrtS. Les niveaux d'expression des gènes prtH+ et prtH+WANS ont été mesurés par RT-PCR quantitative dans les mutants correspondants comparés à celui du gène prtS dans la souche sauvage LMD-9. Les niveaux d'expression des deux gènes recombinants, quel que soit le motif d'ancrage, ont atteint jusqu'à 76% du niveau d'expression de prtS. Les CEP ont été recherchées et identifiées sur la surface de la souche sauvage LMD-9 et des 2 mutants PrtH+ et PrtH+WANS en utilisant la technique du shaving suivie par l'identification des peptides par spectrométrie de masse, ce qui démontre que la sécrétion hétérologue et l'ancrage d'une protéine de plus de 200 kDa était efficace. L'ancrage à la paroi cellulaire semble être plus efficace lorsque le motif LPXTG de PrtS a été utilisé à la place du motif S-layer de PrtH.
CONCLUSIONS:
Nous avons démontré que S. thermophilus LMD-9 était capable de sécréter une protéine hétérologue de poids moléculaire élevé, et probablement de l'ancrer de manière covalente à la paroi cellulaire.
From fundamental studies to industrial processes, synthesis of heterologous protein by micro-organisms is widely employed. The secretion of soluble heterologous proteins in the extracellular medium facilitates their recovery, while their attachment to the cell surface permits the use of the recombinant host cells as protein or peptide supports. One of the key points to carry out heterologous expression is to choose the appropriate host. We propose to enlarge the panel of heterologous secretion hosts by using Streptococcus thermophilus LMD-9. This lactic acid bacterium has a generally recognised as safe status, is widely used in the manufacture of yogurts, fermented milks and cheeses, and is easy to transform by natural competence. This study demonstrates the feasibility of secretion of a heterologous protein anchored to the cell surface by S. thermophilus. For this, we used the cell envelope proteinase (CEP) PrtH of Lactobacillus helveticus CNRZ32 CIRM-BIA 103.
Using S. thermophilus LMD-9 as the background host, three recombinant strains were constructed: i) a negative control corresponding to S. thermophilus PrtS- mutant where the prtS gene encoding its CEP was partially deleted; ii) a PrtH+ mutant expressing the L. helveticus PrtH pro-protein with its own motif (S-layer type) of cell-wall attachment and iii) a PrtH+WANS mutant expressing PrtH pro-protein with the LPXTG anchoring motif from PrtS. The PrtH+ and PrtH+WANS genes expression levels were measured by RT-qPCR in the corresponding mutants and compared to that of prtS gene in the strain LMD-9. The expression levels of both fused prtH CEPs genes, regardless of the anchoring motif, reached up-to more than 76% of the wild-type prtS expression level. CEPs were sought and identified on the cell surface of LMD-9 wild-type strain, PrtH+ and PrtH+WANS mutants using shaving technique followed by peptide identification with tandem mass spectrometry, demonstrating that the heterologous secretion and anchoring of a protein of more than 200 kDa was efficient. The anchoring to the cell-wall seems to be more efficient when the LPXTG motif of PrtS was used instead of the S-layer motif of PrtH.
We demonstrated S. thermophilus LMD-9 could heterologously secrete a high molecular weight protein and probably covalently anchor it to the cell-wall.
J Alzheimers Dis, 41 (2), pp. 377-386.
Sauvée, M., DidierLaurent, G., Latarche, C., Escanyé, M.-C., Olivier, J.-L., Malaplate-Armand, C.
Cerebrospinal fluid (CSF) biomarkers have recently been included in the criteria for the diagnosis of Alzheimer's disease (AD). Since interpretation of CSF profile requires the combination of three parameters, biological data are not always conclusive and isolated elevation of phosphorylated tau (P-tau) or reduction of amyloid-β (Aβ)42 alone can be observed. In these cases, Aβ42/Aβ40 ratio could be more relevant than Aβ42 absolute values by considering inter-individual variations in the total amyloid load.
The objective of this study was to assess the use of Aβ42/Aβ40 ratio to improve the accuracy of biological conclusions in the diagnosis of patients with ambiguous CSF Aβ42 or tau results.
Among 386 lumbar punctures analyzed in the lab in 2 years, 122 showed ambiguous biological data that were completed by CSF Aβ40 quantification and Aβ42/Aβ40 ratio calculation. A biological conclusion was then made using 0.05 as the Aβ42/Aβ40 ratio cut-off.
Our results showed that one-third of the biological profiles of patients with atypical dementia were ambiguous. The addition of Aβ42/Aβ40 ratio increased the proportion of interpretable biological profiles from 69% to 87%, without changing the conclusion when usual biomarkers (Aβ42 and P-tau) were concordant.
Our results support the use of the Aβ42/Aβ40 ratio in addition to the usual CSF AD biomarkers for patients with ambiguous biological profiles. This method could be specifically directed to this population in order to improve the level of certainty for clinical routine practice.
Emirates Journal of Food and Agriculture, 26 (4), pp. 309-316.
El Hatmi, H., Jrad, Z., Khorchani, T., Dary, A., Girardet, J.-M.
The aim of this study was to investigate the radical-scavenging properties towards a stable radical cation, ABTS, of Camelus dromedarius whey proteins (CWP) separated onto a cation-exchanger by fast protein liquid chromatography. The highest activities were found for CWP and fraction F1 mainly composed of a-lactalbumin. Fractions F2, F3 and F4 contained a mixture of lactoferrin, immunoglobulins G and probably camel whey basic protein (CWBP). These three fractions displayed low radical-scavenging activities. Lactoferrin was eluted almost pure in the last fraction (F5) but did not possess detectable radical-scavenging activity. The present results suggested that the cation-exchange chromatography is of great interest to yield, in a single step, whey protein fractions with various biological activities, i.e. a highly-enriched α-lactalbumin fraction displaying efficient antioxidant activity, a fraction (pool of F2-F4) mainly composed of heavy-chain immunoglobulins potentially interesting for human therapy and a fraction of pure lactoferrin having numerous biological activities such as antimicrobial and immunomodulating properties.
International Dairy Journal, 31 (2), pp. 55-61.
Baglinière, F., Matéos, A., Tanguy, G., Jardin, J., Briard-bion, V., Rousseau, F., Robert, B., Beaucher, E., Gaillard, J.-L., Amiel, C., Humbert, G., Dary, A., Gaucheron, F.
Destabilisation of ultra high temperature (UHT) treated milk has been linked to residual proteolytic activity after UHT treatment. To understand the physico-chemical modifications of casein micelles by the protease AprX, produced by Pseudomonas fluorescens F, this enzyme was purified and added to raw milkbefore UHT treatment. Destabilisation of the UHT milk, over three months of storage, was investigated at macroscopic, colloidal and molecular scales. A visual destabilisation appeared progressively over time. At colloidal scale, aggregates were formed and a parallel decrease in zeta potential and hydration of casein micelles was observed. At molecular scale, peptides were released from casein micelles and identified by reversed-phase liquid chromatography coupled with tandem mass spectrometry. The alpha-S1-, alpha-S2-, beta- and kappa-caseins were hydrolysed, with a preference for beta-casein. The results were consistent with the proposition that proteolysis by Ps. fluorescens leading to the destabilisation of milk was due to the activity of AprX.
Food and Chemical Toxicology, 56, pp. 371-380.
Chahin, A., Peiffer, A., Olry, J-C., Crepeaux, G., Schroeder, H., Rychen, G., Guiavarc’h, Y.
Little is known in terms of multi-matrix cytochrome P450 activity induction under repeated oral exposure
to planar halogenated and polycyclic aromatic hydrocarbons (PHH, PAH). In the present study, 60
rats were daily exposed, during 28 days, to oral ingestion of a mixture consisting of phenanthrene, pyrene
and benzo(a)pyrene at 0, 6 or 600 lg/day. EROD activity, reflecting almost exclusively CYP1A1 and
CYP1B1 activities, was measured in brain and liver microsomes as well as in peripheral blood lymphocytes
(PBLs). All induction kinetics could be appropriately fitted using logistic-like models. After 28 days
of exposure to a 6 lg/day dose, EROD activity was found to be 91, 152 and 94-fold increased in lymphocytes,
liver and brain, respectively, compared to day 0. Plateau activities could be appropriately fitted versus
ingested doses using Hill or Michaelis–Menten models. Correlations between matrices made it
possible to conclude that EROD activity in PBL should be considered as a sensitive, convenient and
non-destructive approach for (i) evaluating EROD activity in liver, which was found to represent 98%
of the observed EROD activities in the three tested matrices and (ii) evaluating oral exposure of homogeneous
groups of farm animals (race, diet) to CYP inducing PAH and PHH.
Journal of Dairy Science, 96 (9), pp. 5544-5555.
Chang, O.-K., Seol, K.-H., Jeong, S.-G., Oh, M.-H., Park, B.-Y., Perrin, C., Ham, J.-S.
Toxicology Letters, 221 (1), pp. 40-46.
Crepeaux, G., Bouillaud-Kremarik, P., Sikhayeva, N., Rychen, G., Soulimani, R., Schroeder, H.
Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants originating from incompletecombustion processes. Humans are mainly exposed through contaminated food ingestion. PAHs are neu-rotoxic compounds both for human and rodents, and may be found in placenta, umbilical cord blood andbreast milk, suggesting that early exposure may impact developing central nervous system.In a previous study we showed that PAH exposure during both gestation and lactation periods in ratsincreased anxiety-related behaviours and decreased cerebral metabolism in several key structures linkedto the limbic system on male pups at the adult stage. The aim of the present study was to assess the effectsof an exclusive gestational PAH exposure on the same aspects of brain functionality. Female rats wereexposed through diet to a 16 PAH mixture at doses of 2 g/kg/day or 200 g/kg/day during gestation.Late neurotoxic effects were evaluated by carrying out behavioural and cognitive tests and histochemicalanalyses using cytochrome oxidase activity as a cerebral metabolism marker in different brain areas.The results of this study revealed that behaviour and cerebral metabolism on prenatally PAH exposedadult rats was not significantly affected by the exposure to these pollutants. Finally this work highlights that the exposure period to pollutants such as PAHs at very early stages ofdevelopment play a key role on the neurological impairment induced.
Neurotoxicology, 38, pp. 74-83.
Domange, C., Schroeder, H., Violle, N., Peiffer, J., Canlet, C., Paris, A., Priymenko, N.
C57BL/6J mice orally exposed to 9% H. radicata (HR) are metabolically competent laboratory animals which can be used as model of Australian stringhalt, a neurological horse disease induced by HR ingestion. So, the present study was conducted to assess the brain metabolome and the behavioural performances of mice fed with a 9%-HR-based diet for 21 days. By the end of the period of exposure, mice were investigated for motor activity and coordination, anxiety level, learning and memory performances, social behaviour and rewarding properties of for the plant. Thus, the animals were sacrificed and the brain metabolome was studied using 1H NMR spectroscopy. HR-exposed mice displayed a motor hyperactivity in several tasks, a less resignation in the forced swimming test, and paradigm place preference for the plant. A bootstrap-based regularized canonical analysis performed on merged behavioural and metabolic datasets showed a clear relationship in HR-treated mice between an increase in cerebral scyllo-inositol, an increased motor activity, and seemingly rewarding properties of HR. These results underlie the interest of such a dual approach to characterize functional end-points of a pathophysiological model of the Australian stringhalt in equine species.
Chem Biol Interact, 206 (2), pp. 356-363.
Fabian, J., Hanekamp, W., Thomas, M.H., Olivier, J.-L., Lehr, M.
Cytosolic phospholipase A2α (cPLA2α) plays a key role in the pathogenesis of many inflammatory diseases, such as rheumatoid arthritis, atopic dermatitis and Alzheimer's disease. Therefore, inhibition of this enzyme is assumed to provide a novel therapeutic option for the treatment of these maladies. In this study we investigated the metabolism of the potent cPLA2α inhibitors 1-[3-(4-phenoxyphenoxy)-2-oxopropyl]indole-5-carboxylic acid (1) and 3-isobutanoyl-1-[3-(4-phenoxyphenoxy)-2-oxopropyl]indole-5-carboxylic acid (2). Incubation of 1 with a mixture of human recombinant CYP1A2, 2C8, 2C9, 2C19, 2D6, 3A4 and NADPH-cytochrome P450 reductase enzymes led to reduction of its keto group and to hydroxylation at the terminal phenoxy residue. To identify the enzymes responsible for the observed reactions, experiments with isoform inhibitors were performed. In rat liver S9 fractions the only metabolite found was the alcohol 3 formed by the reduction of the keto group of 1. This reaction here was mainly catalyzed by cytosolic short-chain dehydrogenases/reductases (cSDR) as shown by inhibition experiments with different carbonyl reductase inhibitors. Furthermore, the metabolic stability of 2 in mouse brains was studied after intracerebroventricular application of this compound into the right brain hemispheres of mice. HPLC/MS analyses revealed that 2 is also readily reduced in the brain to an inactive alcohol metabolite most likely by carbonyl reductases.
Applied Microbiology and Biotechnology, 97 (22), pp. 9787-9799.
Hafeez, Z., Cakir-Kiefer, C., Girardet, J.-M., Jardin, J., Perrin, C., Dary, A., Miclo, L.
The trend to confer new functional properties to fermented dairy products by supplementation with bioactive peptides is growing in order to encounter the challenge of health-promoting foods. But these functional ingredients have not to be hydrolysed by proteases of bacteria used in the manufacture of these products. One of the two yoghurt bacteria, Streptococcus thermophilus, has long been considered as weakly proteolytic since its only cell wall-associated subtilisin-like protease, called PrtS, is not always present. Nevertheless, a recent study pointed out a possible peptidase activity in certain strains. In this present study, the stability of milk-derived bioactive peptides, e.g. the anxiolytic peptide, αs1-CN-(f91-97), in the presence of two different S. thermophilus strains with PrtS+ or PrtS− phenotype was studied. Both strains appeared to be capable of hydrolysing the αs1-CN-(f91-97) and other bioactive peptides by recurrent removal of N-terminal residues. The hydrolysis was neither due to intracellular peptidases nor to HtrA protease. Results obtained showed that the observed activity originates from the presence at the surface of both strains of an extracellular aminopeptidase activity. Moreover, a cell wall-associated X-prolyl dipeptidyl peptidase activity was also highlighted when β-casomorphin-7 was used as substrate. All of these findings suggest that, in order to use fermented milks as vector of bioactive peptides, the stability of these bioactive peptides in this kind of products implies to carefully characterize the potential action of the surface proteolytic enzymes of S. thermophilus.
PlosOne, 8 (8), e71713.
Peiffer, J., Cosnier, F., Grova, N., Nunge, H., Salquebre, G., Decret, M.J., Cossec, B., Rychen, G., Appenzeller, B.M., Schroeder, H.
Fluorene is one of the most abundant polycyclic aromatic hydrocarbons in air and may contribute to the neurobehavioral alterations induced by the environmental exposure of humans to PAHs. Since no data are available on fluorene neurotoxicity, this study was conducted in adult rats to assess the behavioral toxicity of repeated fluorene inhalation exposure. Male rats (n?=?18/group) were exposed nose-only to 1.5 or 150 ppb of fluorene 6 hours/day for 14 consecutive days, whereas the control animals were exposed to non-contaminated air. At the end of the exposure, animals were tested for activity and anxiety in an open-field and in an elevated-plus maze, for short-term memory in a Y-maze, and for spatial learning in an eight-arm maze. The results showed that the locomotor activity and the learning performances of the animals were unaffected by fluorene. In parallel, the fluorene-exposed rats showed a lower level of anxiety than controls in the open-field, but not in the elevated-plus maze, which is probably due to a possible difference in the aversive feature of the two mazes. In the same animals, increasing blood and brain levels of fluorene monohydroxylated metabolites (especially the 2-OH fluorene) were detected at both concentrations (1.5 and 150 ppb), demonstrating the exposure of the animals to the pollutant and showing the ability of this compound to be metabolized and to reach the cerebral compartment. The present study highlights the possibility for a 14-day fluorene exposure to induce some specific anxiety-related behavioral disturbances, and argues in favor of the susceptibility of the adult brain when exposed to volatile fluorene.
Toxicology and Applied Pharmacology, 271 (2), pp. 175-183.
Schellenberger, M.T., Grova, N., Farinelle, S., Willième, S., Schroeder, H., Muller, C.P.
Benzo[a]pyrene (B[a]P) is a small molecular weight carcinogen and the prototype of polycyclic aromatic hydrocarbons (PAHs). While these compounds are primarily known for their carcinogenicity, B[a]P and its metabolites are also neurotoxic for mammalian species. To develop a prophylactic immune strategy against detrimental effects of B[a]P, female Balb/c mice immunized with a B[a]P-diphtheria toxoid (B[a]P-DT) conjugate vaccine were sub-acutely exposed to 2mg/kg B[a]P and behavioral performances were monitored in tests related to learning and memory, anxiety and motor coordination. mRNA expression of the NMDA receptor (NR1, 2A and 2B subunits) involved in the above behavioral functions was measured in 5 brain regions. B[a]P induced NMDA1 expression in three (hippocampus, amygdala and cerebellum) of five brain regions investigated, and modulated NMDA2 in two of the five brain regions (frontal cortex and cerebellum). Each one of these B[a]P-effects was reversed in mice that were immunized against this PAH, with measurable consequences on behavior such as anxiety, short term learning and memory. Thus active immunization against B[a]P with a B[a]P-DT conjugate vaccine had a protective effect and attenuated the pharmacological and neurotoxic effects even of high concentrations of B[a]P.
Biochemistry, 52 (48), pp. 8722-8731.
Zidane, F., Zeder-Lutz, G., Altschuh, D., Girardet, J.-M., Miclo, L., Corbier, C., Cakir-Kiefer, C.
Somatic angiotensin I-converting enzyme (ACE) possesses two catalytic domains and plays a major role in the regulation of blood pressure, thus representing a therapeutic target for the treatment of hypertension. We present a comprehensive surface plasmon resonance (SPR) study of the interaction of human somatic ACE with the pharmacological inhibitors captopril and lisinopril, the bradykinin potentiating peptide BPP-11b, and the food peptidic inhibitors from bovine αs2-casein, F(174)ALPQYLK(181) and F(174)ALPQY(179). SPR binding curves recorded with the high potency inhibitors captopril, lisinopril, and BPP-11b were evaluated both by regression analysis and by kinetic distribution analysis. The results indicated that captopril and lisinopril bound ACE with two KD's differing by a factor 10-20 and >30, respectively (lowest KD = 0.1-0.3 nM for both inhibitors). This shows, for the first time in a direct binding assay with the two-domain enzyme, the existence of two binding modes of the pharmacological inhibitors, presumably with the two ACE domains. The BPP-11b-ACE binding curves were complex but showed a predominant interaction with KD in the nanomolar range. The caseinopeptides, known to inhibit ACE with an IC50 of 4.3 μM, bound to ACE with KD = 3-4 μM. Mapping of the F(174)ALPQY(179) binding site on ACE by sequential binding studies using captopril or BPP-11b indicated that it bound to (or near) the two active sites of ACE, in agreement with the stoichiometry of 2 determined from data fitting. Our results provide a detailed characterization of ACE-inhibitor binding modes and validate SPR for predicting the inhibitory potential of new compounds.
Reprod. Fert. Develop. (accepté)
?arski D., Krejszeff S., Pali?ska K., Targo?ska K., Kupren K., Fontaine P., Kestemont P., Kucharczyk D.
FEBS Journal, 279 (23), pp. 4361-4373.
Ahmad, N., Girardet, J.-M., Akbar, S., Lanhers, M.-C., Paris, C., Yen, F.T., Corbier, C.
The hepatic removal of triglyceride-rich chylomicrons during the postprandial phase represents an important step towards determining the bioavailability of dietary lipids amongst the peripheral tissues. Indeed, elevated postprandial lipemia is often associated with obesity and increased risk of coronary heart disease. The milk protein, lactoferrin, has been shown to inhibit hepatic chylomicron remnant removal by the liver, resulting in increased postprandial lipemia. Despite numerous studies on potential targets for lactoferrin, the molecular mechanisms underlying the effect of lactoferrin remain unclear. We recently demonstrated that the lipolysis stimulated lipoprotein receptor (LSR) contributes to the removal of triglyceride-rich lipoproteins during the postprandial phase. Here, we report that while lactoferrin does not have any significant effect on LSR protein levels in mouse Hepa1-6 cells, this protein colocalizes with LSR in cells but only in the presence of oleate, which is needed to obtain LSR in its active form as lipoprotein receptor. Ligand blotting using purified LSR revealed that lactoferrin binds directly to the receptor in the presence of oleate and prevents the binding of triglyceride-rich lipoproteins. Both C- and N-lobes of lactoferrin as well as a mixture of peptides derived from its hydrolysis retained the ability to bind LSR in its active form. We propose then that the elevated postprandial lipemia observed upon lactoferrin treatment in vivo is mediated in part by its direct interaction with free fatty acid activated LSR, thus preventing clearance of chylomicrons and their remnants through the LSR pathway.
Toxicology, 299 (1), pp. 44-54.
Ardzivian Elnar, A., Diesel, B., Desor, F., Feidt, C., Bouayed, J., Kiemer, A.K., Soulimani, R.
Food Chemistry, 135 (4), pp. 2593-2603.
Baglinière, F., Tanguy, G., Jardin, J., Matéos, A., Briard, V., Rousseau, F., Robert, B., Beaucher, E., Humbert, G., Dary, A., Gaillard, J.-L., Amiel, C., Gaucheron, F.
Pseudomonas fluorescens grows at low temperature and produces thermo-resistant protease(s) that can destabilize UHT (Ultra High Temperature) milk during its storage. The consequences of contamination of microfiltered milk with 9 strains of P. fluorescens on the stability of the corresponding UHT milk during storage had been investigated in this study.
The strains were classified in two groups according to their ability to destabilize UHT milk. For the group of highly destabilizing strains, sedimentations of UHT milks, low values to phosphate test and the presence of aggregates were observed. Zeta potential and hydration of casein micelles decreased, whereas non casein nitrogen (NCN) and non protein nitrogen (NPN) contents increased. The analyses of NCN fraction by liquid chromatography coupled to mass spectrometry indicated that the different casein molecules were hydrolyzed in a similar way for the destabilizing strains suggesting that the same enzyme was implicated. For the group of slightly or not destabilizing strains no visual and biochemical alteration were found. This study showed that destabilization of UHT milk by P. fluorescens was highly variable and strain-dependent.
Basic & Clinical Pharmacology & Toxicology, 110 (6), pp. 544-550.
Bouayed, J., Bohn, T., Tybl, E., Kiemer, A.K., Soulimani, R.
Benzo[α]pyrene (B[α]P) is a ubiquitous environmental pollutant exhibiting adverse effects on cognitive function and behaviour. In this study, depressive or antidepressive effects of B[α]P were investigated. Here, we report that a subacute B[α]P oral exposure (0.02-0.2 mg/kg) increases mobility behaviour in female adult mice in the tail suspension test, but not in the forced swimming test, without altering locomotion, suggesting that the tail suspension test was a more sensitive indicator of B[α]P-induced neurobehavioural disturbance. This might be because of differences in neurochemical substrates and pathways, mediating the performance in these behavioural models of depression. The effect of B[α]P on female adult mice in the tail suspension test was similar to that obtained with subacute treatment of the antidepressant reference drug imipramine (10 mg/kg). Therefore, B[α]P at 0.02 mg/kg and 0.2 mg/kg induces an antidepressant-like effect in mice, suggesting a neurobehavioural disturbance after oral exposure to this environmental compound. Furthermore, oral exposure to B[α]P at 0.02 mg/kg significantly increased gene expression levels of the brain receptors 5-hydroxytryptamine (serotonin) 1A (5HT(1A)) and alpha-1D adrenergic (ADRA(1D)). In summary, the presented findings suggest that subacute oral exposure to B[α]P results in behavioural changes in female adult mice, possibly caused by alterations in the serotoninergic and adrenergic systems.
Food Chemistry, 131 (4), pp. 1466-1472.
Bouayed, J., Deußer, H., Hoffmann, L., Bohn, T.
Theriogenology 78(2):432-442.
Castets M.D., Schaerlinger B., Silvestre F., Gardeur J.-N., Dieu M., Corbier C., Kestemont P., Fontaine P.
International Dairy Journal, 23 (2), pp. 91-98.
Chang, O.K., Perrin, C., Galia, W., Saulnier, F., Miclo, L., Roux, E., Driou, A., Humbert, G., Dary, A.
PrtS is the sole cell envelope protease (CEP) characterized in Streptococcus thermophilus. It is believed that it is anchored to the cell wall by sortase A (SrtA) through the LPXTG motif present at its C-terminus. Two soluble proteases corresponding to PrtS in its proenzyme and mature form were detected in the supernatant of S. thermophilus strain 4F44. In this strain, 60% of the PrtS molecules are anchored to the cell wall and 40% released in the medium. Such a release might result from a partial deficiency in the strain 4F44 of SrtA, even if its sequence slightly differs from that of S. thermophilus strain LMD-9, in which PrtS is anchored. Indeed, the presence of an intact LPXTG motif at the C-terminus of the released proteases showed that the linking process driven by SrtA did not occur and these proteases were not released by proteolysis after their anchoring.
Toxicology Letters, 211 (2), pp. 105-113.
Crépeaux, G., Bouillaud-Kremarik, P., Sikhayeva, N., Rychen, G., Soulimani, R., Schroeder, H.
Environmental Science and Technology, 46 (11), pp. 6252-6260.
Denys, S., Caboche, J., Tack, K., Wragg, J., Cave, M., Jondreville, C., Feidt, C.
Neurobiol Aging, 33 (6), pp. e17-e29.
Desbene, C., Malaplate-Armand, C., Youssef, I., Garcia, P., Stenger, C., Sauvée, M., Fischer, N., Rimet, D., Koziel, V., Escanyé, M.-C., Oster, T., Kriem, B., Yen, F.T., Pillot, T., Olivier, J.-L.
Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ oligomers activate cytosolic phospholipase A(2) (cPLA(2)), which specifically releases arachidonic acid from membrane phospholipids. We here observed that cPLA(2) gene inactivation prevented the alterations of cognitive abilities and the reduction of hippocampal synaptic markers levels noticed upon a single intracerebroventricular injection of Aβ oligomers in wild type mice. We further demonstrated that the Aβ oligomer-induced sphingomyelinase activation was suppressed and that phosphorylation of Akt/protein kinase B (PKB) was preserved in neuronal cells isolated from cPLA(2)(-/-) mice. Interestingly, expression of the Aβ precursor protein (APP) was reduced in hippocampus homogenates and neuronal cells from cPLA(2)(-/-) mice, but the relationship with the resistance of these mice to the Aβ oligomer toxicity requires further investigation. These results therefore show that cPLA(2) plays a key role in the Aβ oligomer-associated neurodegeneration, and as such represents a potential therapeutic target for the treatment of Alzheimer's disease.
Fish Physiol. Biochem., 38, 389-399
Dorts J., Grenouillet G., Douxfils J., Mandiki R., Milla S., Kestemont P.
Fish Shellfish Immunol., 33, 1112-112
Douxfils J., Deprez M., Mandiki S.N.M., Milla S., Henrotte E., Mathieu C., Silvestre F., Vandecan M., Rougeot C., Mélard C., Dieu M., Raes M., Kestemont P.
PLoS One, 7 (12), e52567.
Dukic-Stefanovic, S., Walther, J., Wosch, S., Zimmermann, G., Wiedemann, P., Alexander H., Claudepierre, T.
Extra-gonadal role of gonadotropins has been re-evaluated over the last 20 years. In addition to pituitary secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH), the CNS has been clearly identified as a source of hCG acting locally to influence behaviour. Here we demonstrated that human retina is producing this gonadotropin that acts as a neuroactive molecule. Müller glial and retinal pigmented epithelial (RPE) cells are producing hCG that may affects neighbour cells expressing its receptor, namely cone photoreceptors. It was previously described that amacrine and retinal ganglion (RGC) cells are targets of the gonadotropin releasing hormone that control the secretion of all gonadotropins. Therefore our findings suggest that a complex neuroendocrine circuit exists in the retina, involving hCG secreting cells (glial and RPE), hCG targets (photoreceptors) and hCG-release controlling cells (amacrine and RGC). The exact physiological functions of this circuit have still to be identified, but the proliferation of photoreceptor-derived tumor induced by hCG demonstrated the need to control this neuroendocrine loop.
PlosOne, 7 (4), pp. 1-9.
Egea, P.F., Muller-Steffner, H., Kuhn, I., Cakir-Kiefer, C., Oppenheimer, N.J., Stroud, R.M., Kellenberger, E., Schuber, F.
Bovine CD38/NAD+glycohydrolase (bCD38) catalyses the hydrolysis of NAD+ into nicotinamide and ADP-ribose and the formation of cyclic ADP-ribose (cADPR). We solved the crystal structures of the mono N-glycosylated forms of the ecto-domain of bCD38 or the catalytic residue mutant Glu218Gln in their apo state or bound to aFNAD or rFNAD, two 2′-fluorinated analogs of NAD+. Both compounds behave as mechanism-based inhibitors, allowing the trapping of a reaction intermediate covalently linked to Glu218. Compared to the non-covalent (Michaelis) complex, the ligands adopt a more folded conformation in the covalent complexes. Altogether these crystallographic snapshots along the reaction pathway reveal the drastic conformational rearrangements undergone by the ligand during catalysis with the repositioning of its adenine ring from a solvent-exposed position stacked against Trp168 to a more buried position stacked against Trp181. This adenine flipping between conserved tryptophans is a prerequisite for the proper positioning of the N1 of the adenine ring to perform the nucleophilic attack on the C1′ of the ribofuranoside ring ultimately yielding cADPR. In all structures, however, the adenine ring adopts the most thermodynamically favorable anti conformation, explaining why cyclization, which requires a syn conformation, remains a rare alternate event in the reactions catalyzed by bCD38 (cADPR represents only 1% of the reaction products). In the Michaelis complex, the substrate is bound in a constrained conformation; the enzyme uses this ground-state destabilization, in addition to a hydrophobic environment and desolvation of the nicotinamide-ribosyl bond, to destabilize the scissile bond leading to the formation of a ribooxocarbenium ion intermediate. The Glu218 side chain stabilizes this reaction intermediate and plays another important role during catalysis by polarizing the 2′-OH of the substrate NAD+. Based on our structural analysis and data on active site mutants, we propose a detailed analysis of the catalytic mechanism.
Environmental Science and Pollution Research, 19 (2), pp. 440-447.
Fournier, A., Feidt, C., Marchand, P., Vénisseau, A., Le Bizec, B., Sellier, N., Engel, E., Ratel, J., Travel, A., Jondreville, C.
Introduction: High concentrations of hexabromocyclododecane (HBCD) sometimes recorded in free-range hens' eggs are thought to be due to soil ingestion. Of the three stereoisomers of HBCD (α-, β-, and γ-HBCD), γ-HBCD is the main component in the commercial mixture, as well as in environmental matrices, whereas the isomer profile is α-dominated in biota. In fish and in mammals, this shift is thought to be due to a rapid elimination of γ-HBCD and to its bioisomerization to the more persistent α-HBCD. The aim of the current controlled study was to better understand the fate of ingested HBCD in laying hens. The isomer profile in soil being γ-dominated, excretion kinetics of γ-HBCD into egg yolk, and accumulation in liver and in abdominal fat were investigated. Materials and methods: Forty-eight laying hens were individually housed and fed with a spiked diet containing 1.1-ng γ-HBCD per gram for 21 days and with a clean diet for the following 18 days. Hens were sequentially slaughtered throughout the 39-day experiment. α-, β-, and γ-HBCD were analyzed in egg yolk, in abdominal fat, and in liver by LC-MS/MS. α- and γ-HBCD were quantified in the three tissues, while β-HBCD was never quantified. Results and conclusion: Kinetics of the two isomers suggests that γ-HBCD is rapidly biotransformed and eliminated, and partly isomerized into the more persistent α-HBCD. Carry-over rate of ingested γ-HBCD to egg yolk was estimated at 1.2%. Estimated half-lives of γ-HBCD in egg yolk, in abdominal fat, and in liver were 2.9, 13, and 0.41 days, respectively.
Chemosphere, 88 (3), pp. 300-306.
Fournier, A., Feidt, C., Travel, A., Le Bizec, B., Vénisseau, A., Marchand, P., Jondreville, C.
Fish Physiol. Biochem., 38, 1619-1626
Gennotte V, Sawadogo P., Milla S., Kestemont P., Mélard C., Rougeot C.
Aquat. Toxicol., 122-123, 181-187
Hatef A., Hadi Alavi S.M., Milla S., K?iš?an J., Golshan M., Fontaine P., Linhart O.
Ecotox. Environ. Safe, 76 (1), pp. 56-62.
Hatef, A., Alavi, S.M.H., Abdulfatah, A., Fontaine, P., Rodina, M., Linhart, O.
ANIMAL, 6 (8), pp. 1350-1359.
Jurjanz, S., Feidt, C., Perez-Prieto, L.A., Ribeiro filho, H.M.N., Rychen, G., Delagarde, R.
Involuntary soil intake by cows on pasture can be a potential route of entry for pollutants into the food chain. It therefore appears necessary to know and quantify factors affecting soil intake in order to ensure the food safety in outside rearing systems. Thus, soil intake was determined in two Latin-square trials with 24 and 12 lactating dairy cows. In Trial 1, the effect of pasture allowance (20 vs 35 kg dry matter (DM) above ground level/cow daily) was studied for two sward types (pure perennial ryegrass vs mixed perennial ryegrass/white clover) in spring. In Trial 2, the effect of pasture allowance (40 vs 65 kg DM above ground level/cow daily) was studied at two supplementation levels (0 or 8 kg dry matter of a maize-silage-based supplement) in autumn. Soil intake was determined by the method based on acid insoluble ash used as an internal marker. The daily dry soil intake ranged, between treatments, from 0.17 to 0.83 kg/cow in Trial 1 and from 0.15 to 0.85 kg/cow in Trial 2, reaching up to 1.3 kg during some periods. In both trials, soil intake increased with decreasing pasture allowance, by 0.46 and 0.15 kg in trials 1 and 2, respectively. In Trial 1, this pasture allowance effect was greater on mixed swards than on pure ryegrass swards (0.66 vs 0.26 kg reduction of daily soil intake between medium and low pasture allowance, respectively). In trial 2, the pasture allowance effect was similar at both supplementation levels. In trial 2, supplemented cows ate much less soil than unsupplemented cows (0.20 vs 0.75 kg/d, respectively). Differences in soil intake between trials and treatments can be related to grazing conditions, particularly pre-grazing and post-grazing sward height, determining at least in part the time spent grazing close to the ground. A post-grazing sward height lower than 50 mm can be considered as a critical threshold. Finally, a dietary supplement and a low grazing pressure, i.e. high pasture allowance increasing post-grazing sward height, would efficiently limit the risk for high level of soil intake, especially when grazing conditions are difficult. Pre-grazing and post-grazing sward heights, as well as faecal crude ash concentration appear to be simple and practical tools for evaluating the risk for critical soil intake in grazing dairy cows.
Environmental Science and Pollution Research, 19(7): 2802-2812.
Lazartigues A., Banas D., Feidt C., Brun-Bellut J., Thomas M.
JOURNAL OF DAIRY SCIENCE Volume: 95 Issue: 4 Pages: 1956-1970
Lerch S, Ferlay A, Pomies D, Martin B, Pires JAA, Chilliard Y
JOURNAL OF DAIRY SCIENCE Volume: 95 Issue: 9 Pages: 5221-5241
Lerch S, Ferlay A, Shingfield KJ, Martin B, Pomies D, Chilliard Y
JOURNAL OF DAIRY SCIENCE Volume: 95 Issue: 12 Pages: 7269-7287
Lerch S, Shingfield KJ, Ferlay A, Vanhatalo A, Chilliard Y
LETOURNEAU-MONTMINY M.-P., JONDREVILLE C., SAUVANT D., NARCY A.,
Optimizing phosphorus (P) utilization in pigs requires improving our capacity to predict the amount of P absorbed and retained, with the main modulating factors taken into account, as well as precisely determining the P requirements of the animals. Given the large amount of published data on P utilization in pigs, a meta-analysis was performed to quantify the impact of the different dietary P forms, calcium (Ca) and exogenous phytases on the digestive and metabolic utilization criteria for dietary P in growing pigs. Accordingly, the amount of phytate P (PP) leading to digestible P (g/kg) was estimated to be 21%, compared with 73% for non-phytate P (NPP) from plant ingredients and 80% for NPP from mineral and animal ingredients (P < 0.001). The increase in total digestible dietary P following the addition of microbial phytase (PhytM) from Aspergillus niger (P < 0.001) was curvilinear and about two times higher than the increase following the addition of plant phytase, which leads to a linear response (P < 0.001). The response of digestible P to PhytM also depends on the amount of substrate, PP (PhytM(2) × PP, P < 0.001). The digestibility of dietary P decreased with dietary Ca concentration (P < 0.01) independently of phytase but increased with body weight (BW, P < 0.05). Although total digestible dietary P increased linearly with total NPP concentration (P < 0.001), retained P (g/kg), average daily gain (ADG, g/day) and average daily feed intake (ADFI, g/day) increased curvilinearly (P < 0.001). Interestingly, whereas dietary Ca negatively affected P digestibility, the effect of dietary Ca on retained P, ADG and ADFI depended on total dietary NPP (NPP × Ca, P < 0.01, P < 0.05 and P < 0.01, respectively). Increasing dietary Ca reduced retained P, ADG and ADFI at low NPP levels, but at higher NPP concentrations it had no effect on ADG and ADFI despite a positive effect on retained P. Although the curvilinear effect of PhytM on digestible P increased with PP (P < 0.001), this effect was lessened by total NPP for ADG and ADFI (PhytM × NPP and PhytM(2) × NPP, P < 0.05) and depended on both total NPP and Ca for retained P (PhytM(2) × NPP × Ca, P < 0.01). This meta-analysis improves our understanding of P utilization, with major modulating factors taken into account. The information generated will be useful for the development of robust models to formulate environmentally friendly diets for growing pigs.
Animal, 6 (10), pp. 1590-1600.
Létourneau-montminy, M.-P., Jondreville, C., Sauvant, D., Narcy, A.
PloS One, 7 (9), pp. e43053--.
Lhomme, P., Ayasse, M., Valterová, I., Lecocq, T., Rasmont, P.
Social parasites exploit the colony resources of social insects. Some of them exploit the host colony as a food resource or as a shelter whereas other species also exploit the brood care behavior of their social host. Some of these species have even lost the worker caste and rely completely on the host's worker force to rear their offspring. To avoid host defenses and bypass their recognition code, these social parasites have developed several sophisticated chemical infiltration strategies. These infiltration strategies have been highly studied in several hymenopterans. Once a social parasite has successfully entered a host nest and integrated its social system, its emerging offspring still face the same challenge of avoiding host recognition. However, the strategy used by the offspring to survive within the host nest without being killed is still poorly documented. In cuckoo bumblebees, the parasite males completely lack the morphological and chemical adaptations to social parasitism that the females possess. Moreover, young parasite males exhibit an early production of species-specific cephalic secretions, used as sexual pheromones. Host workers might thus be able to recognize them. Here we used a bumblebee host-social parasite system to test the hypothesis that social parasite male offspring exhibit a chemical defense strategy to escape from host aggression during their intranidal life. Using behavioral assays, we showed that extracts from the heads of young cuckoo bumblebee males contain a repellent odor that prevents parasite males from being attacked by host workers. We also show that social parasitism reduces host worker aggressiveness and helps parasite offspring acceptance.
Exp Eye Res., 96 (1), pp. 24-35.
Li, Y.-N., Pinzon-Duarte, G., Dattilo, M., Claudepierre, T., Koch, M., Brunken, W.J.
Netrin-4, a member of the netrin family, is a potent regulator of embryonic development. It promotes neurite extension and regulates pulmonary airway branching, vasculogenesis patterning, and endothelial proliferation in pathological angiogenesis. The initial characterization of netrin-4 expression was focused on epithelial-derived organs (kidney, lung and salivary gland) and the central nervous system. Ocular development is an ideal system to study netrin-4 expression and function, as it involves both ectodermal (cornea, lens and retina) and mesodermal (sclera and choroid) derivatives and has an extensive and well-characterized angiogenic process. Netrin-4 is expressed in all ocular tissues. It is a prominent component of the basement membranes of the lens and cornea, as well as all three basement membranes of the retina: the inner limiting membrane, vascular basement membranes, and Bruch's membrane. Netrin-4 is differentially deposited in vascular basement membranes, with more intense anti-netrin-4 reactivity on the arterial side. The retinal microcirculation also expresses netrin-4. In order to test the function of netrin-4 in vivo, we generated a conventional mouse lacking Ntn4 expression. Basement membrane formation in the cornea, lens and retina is undisrupted by netrin-4 deletion, demonstrating that netrin-4 is not a major structural component of these basement membranes. In the Ntn4 homozygous null (Ntn4-/-) cornea, the overall morphology of the cornea, as well as the epithelial, stromal and endothelial stratification are normal; however, epithelial cell proliferation is increased. In the Ntn4-/- retina, neurogenesis appears to proceed normally, as does retinal lamination. In the Ntn4-/- retina, retinal ganglion cell targeting is intact, although there are minor defects in axon fasciculation. In the retinal vasculature of the Ntn4-/- retina, the distribution patterns of astrocytes and the vasculature are largely normal, with the possible exception of increased branching in the deep capillary plexus, suggesting that netrin-4 may act as a negative regulator of angiogenesis. These data, taken together, suggest that netrin-4 is a negative regulator of corneal epithelial cell proliferation and retinal vascular branching in vivo, whereas netrin-4 may be redundant with other members of the netrin family in other ocular tissue development. Ntn4-/- mice may serve as a good model in which to study the role of netrins in vivo of the pathobiologic vascular remodeling in the retina and cornea.
Journal of Agricultural and Food Chemistry, 60 (2), pp 554-565.
Miclo, L., Roux, E., Genay, M., Brusseaux, E., Poirson, C., Jameh, N., Perrin, C., Dary, A.
Milk proteins contain numerous potential bioactive peptides, which may be released by digestive proteases or by the proteolytic system of lactic acid bacteria during food processing. The capacity of Streptococcus thermophilus to generate peptides, especially bioactive peptides, from bovine caseins was investigated. Strains expressing various levels of the Cell Envelope Proteinase, PrtS, were incubated either with αs1-, αs2- or β-casein. Analysis of the supernatants by LC-ESI-MS/MS showed that the β-casein was preferentially hydrolyzed first, followed by αs2-casein and then αs1-casein. Numbers and types of peptides released were strain-dependent. Hydrolysis appeared to be linked with the accessibility of different casein regions by protease. Analysis of bonds hydrolyzed in the region 1-23 of αs1-casein suggests that PrtS is at least in part responsible for the peptide production. Finally, among the generated peptides, 13 peptides from β-casein, 5 from αs2-casein and 2 from αs1-casein have been reported as bioactive, 15 of them being angiotensin-converting enzyme inhibitors.
Fish Physiol. Biochem., 38, 1287-1298
Nyina-wamwiza L., Defreyne P.S., Ngendahayo L., Milla S., Mandiki R.
Theriogenology 77, 184-194.
Nyina-wamwiza L., Milla S., Pierrard M.A., Rurangwa E., Mandiki R., Van Look K.J.W., Kestemont P.
J Neurochem, 123 (4), pp. 467-476.
Stenger, C., Pinçon, A., Hanse, M., Royer, L., Koziel, V., Comte, A., Olivier, J.-L., Pillot, T., Yen, F.T.
Brain lipid homeostasis is important for maintenance of brain cell function and synaptic communications, and is intimately linked to age-related cognitive decline. Because of the blood–brain barrier’s limiting nature, this tissue relies on a complex system for the synthesis and receptor-mediated uptake of lipids between the different networks of neurons and glial cells. Using immunofluorescence, we describe the region-specific expression of the lipolysis-stimulated lipoprotein receptor (LSR), in the mouse hippocampus, cerebellum Purkinje cells, the ependymal cell interface between brain parenchyma and cerebrospinal fluid, and the choroid plexus. Colocalization with cell-specific markers revealed that LSR was expressed in neurons, but not astrocytes. Latency in arms of the Y-maze exhibited by young heterozygote LSR+/ mice was significantly different as compared to control LSR+/+, and increased in older LSR+/ mice. Filipin and Nile red staining revealed membrane cholesterol content accumulation accompanied by significantly altered distribution of LSR in the membrane, and decreased intracellular lipid droplets in the cerebellum and hippocampus of old LSR+/ mice, as compared to control littermates as well as young LSR+/ animals. These data therefore suggest a potential role of LSR in brain cholesterol distribution, which is particularly important in preserving neuronal integrity and thereby cognitive functions during aging.
Ecotoxicology and Environmental Safety, 77 (1), pp. 35-44.
Thomas, M., Lazartigues, A., Banas, D., Brun-Bellut, J., Feidt, C.
Neurochem Res, 37 (7), pp. 1524-1533.
Unterlauft, J.D., Eichler, W., Kuhne, K., Yang, X.M., Yafai, Y., Wiedemann, P., Reichenbach, A., Claudepierre, T.
Survival of retinal ganglion cells (RGC) is compromised in several vision-threatening disorders such as ischemic and hypertensive retinopathies and glaucoma. Pigment epithelium-derived factor (PEDF) is a naturally occurring pleiotropic secreted factor in the retina. PEDF produced by retinal glial (Müller) cells is suspected to be an essential component of neuron-glial interactions especially for RGC, as it can protect this neuronal type from ischemia-induced cell death. Here we show that PEDF treatment can directly affect RGC survival in vitro. Using Müller cell-RGC-co-cultures we observed that activity of Müller-cell derived soluble mediators can attenuate hypoxia-induced damage and RGC loss. Finally, neutralizing the activity of PEDF in glia-conditioned media partially abolished the neuroprotective effect of glia, leading to an increased neuronal death in hypoxic condition. Altogether our results suggest that PEDF is crucially involved in the neuroprotective process of reactive Müller cells towards RGC.
Aquaculture Research 43 : 713-721
Zarski D., Kucharczyk D., Targonska K., Palinska K., Kupren K., Fontaine P., Kestemont P.
Food Chemistry, 132 (1), pp. 391-398.
Zidane, F., Matéos, A., Cakir-Kiefer, C., Miclo, L., Rahuel-Clermont, S., Girardet, J.-M., Corbier, C.
To better understand the mechanism of metal ion transport through the gastrointestinal tract to their absorption sites, isothermal titration calorimetry (ITC) was used to investigate the binding of dicationic metals to beta-CN(1–25)4P, a beta-casein tetraphosphorylated peptide. ITC technology was found suitable for studying weak bonds between metal ions and phosphopeptides and provided a direct means of thermodynamic and stoichiometric characterisation of complex formation. Thus, one mole of beta-CN(1–25)4P binds two moles of Ca2+, Mg2+ or Zn2+ under experimental conditions close to those of the ileum (pH 8, 37°C), with rather low binding affinity constants (K = 4900–11,200 M-1). These low affinities should facilitate the release of metal ions during intestinal absorption. By contrast, Cu2+ did not bind to beta-CN(1–25)4P at pH 8, despite its reported significant affinity towards beta-casein and the 1–25 peptide at near-neutral pH.
Ethnozootechnie 90 : 7-12
Teletchea, F.
Aquaculture 322-323: 169-176
Abdulfatah, A., Fontaine, P., Kestemont, P., Gardeur, J.-N., Marie, M.
Environmental Science and Technology, 45 (15), pp. 6584-6591.
Berge, P., Ratel, J., Fournier, A., Jondreville, C., Feidt, C., Roudaut, B., Le Bizec, B., Engel, E.
The study investigated the feasibility of using volatile compound signatures of liver tissues in poultry to detect previous dietary exposure to different types of xenobiotic. Six groups of broiler chickens were fed a similar diet either noncontaminated or contaminated with polychlorinated dibenzo-p-dioxins/-furans (PCDD/Fs; 3.14 pg WHO-TEQ/g feed, 12% moisture), polychlorinated biphenyls (PCBs; 0.08 pg WHO-TEQ/g feed, 12% moisture), polybrominated diphenyl ethers (PBDEs; 1.63 ng/g feed, 12% moisture), polycyclic aromatic hydrocarbons (PAHs; 0.72 mu g/g fresh matter), or coccidiostats (0.5 mg/g feed, fresh matter). Each chicken liver was analyzed by solid-phase microextraction - mass spectrometry (SPME-MS) for volatile compound metabolic signature. and by gas chromatography - high resolution mass spectrometry (GC-HRMS), gas chromatography - tandem mass spectrometry (GC-MS/MS), and liquid chromatography - tandem mass spectrometry (LC-MS/MS) to quantify xenobiotic residues. Volatile compound signature evidenced a liver metabolic response to PAH although these rapidly metabolized xenobiotics are undetectable in this organ by the reference methods. Similarly, the volatile compound metabolic signature enabled to differentiate the noncontaminated chickens from those contaminated with PBDEs or coccidiostats. In contrast, no clear signature was pointed out for slowly metabolized compounds such as PCDD/Fs and PCBs although their residues were found in liver at 50.93 (+/-6.71) and 0.67 (+/-0.1) pg WHO-TEQ/g fat, respectively.
Journal of Medicinal Food, 14 (12), pp, 1631–1637.
Bouayed, J., Hoffmann, L., Bohn, T.
Many health beneficial functions of dietary ingredients, including antimutagenity and anticarcinogenity, have been discussed in relation to their antioxidant properties. In this study, antioxidative mechanisms of whole-apple antioxidants (from seven varieties) were investigated using the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity assay, the ferric-reducing antioxidant power (FRAP) assay, and the ferrous iron(II) chelating activity assay. Results indicated the ability of primary antioxidants to act as hydrogen or electron donors, with considerable differences depending on variety, with ABTS and FRAP values ranging from 270 to 1,142 mg of vitamin C equivalents/100 g and from 695 to 3,143 μmol of Fe/100 g, respectively. However, varieties did not display measurable chelating activity except for Florina and Graham, exhibiting a weak activity (0.1-0.2 μg of EDTA equivalents/100 g). Correlation analyses showed that polyphenols were major primary antioxidants contributing to antioxidative mechanisms (r>0.99, P<.001), whereas their involvement as secondary antioxidants (i.e., as chelating compounds) was negligible. Our findings further showed that the intake of 100 g of apple fruits can provide antioxidants equivalent to approximately 270-1,140 mg of vitamin C, with highest antioxidant concentrations for the older varieties Grauapfel and Goldparmäne.
Food Chemistry, 128 (1), pp. 14-21.
Bouayed, J., Hoffmann, L., Bohn, T.
Neurochem. Res., 36 (8), pp. 1407-1416.
Bougrid, A., Claudepierre, T., Picaud, S., Ayad, G., Mornet, D., Dorbani-Mamine, L., Rendon, A., Darbeida, H.
The dystrophin-associated-protein complex (DAPC) has been extensively characterized in the central nervous system where it is localized both in neuronal and glial cells. Few studies have characterized this complex in the neurohypophysis. To further study this complex in pituicytes, the resident astroglia of the neurophypophysis, we used adult pituicyte cultures and determined the expression and localization of dystrophins/utrophins and the DAPC by RT-PCR, western blotting and immunofluorescence. Our data show that the pituicytes express dystrophins, utrophins and several members of the DAPC including dystroglycans, δ-, γ-sarcoglycans, α-dystrobrevin-1 and α1-syntrophin. Double immunofluorescence analysis shows that laminin colocalizes with dystroglycan, suggesting that similarly to muscle and astrocytes, the DAPC interacts with the extracellular matrix in pituicytes. Collectively these findings show that dystrophins/utrophins and members of the DAPC are expressed in pituicytes where they may form multiprotein complexes and play a role in the retraction-reinsertion of pituicyte endfeet during specific physiological conditions.
Journal of Agricultural and Food Chemistry, 59 (9), pp. 4464-4472.
Cakir-Kiefer, C., Le Roux, Y., Balandras, F., Trabalon, M., Dary, A., Laurent, F., Gaillard, J.-L., Miclo, L.
α-Casozepine is a peptide, corresponding to the sequence 91−100 of the bovine αs1-casein, displaying anxiolytic activity in the rat. The αs1-casein tryptic hydrolysate containing this peptide decreases stress effects after oral administration in various species including man. Therefore, the stability of this peptide toward gastric and pancreatic proteases has been assessed by using pepsin, chymotrypsin/trypsin, Corolase PP, pepsin followed by chymotrypsin/trypsin or pepsin followed by Corolase PP. α-Casozepine was slowly degraded by chymotrypsin, much more sensitive to pepsin and Corolase PP but not completely destroyed after 4 h kinetics. The bonds in the region 91 to 95 of the α-casozepine were totally resistant to hydrolysis by all studied proteases. Surprisingly, a fragment, corresponding to the sequence 91−97 and found in all the hydrolysis media in significant amount, possessed an anxiolytic activity in three behavioral tests measuring this parameter. This peptide could participate in the in vivo activity of α-casozepine.
Journal of Agricultural and Food Chemistry, 59 (22), pp. 11956–11965.
Cakir-Kiefer, C., Miclo, L., Balandras, F., Dary, A., Soligot, C., Le Roux, Y.
α-Casozepine and f91–97, peptides from αs1-casein, display anxiolytic activity in rats and may have to cross the intestinal epithelium to exert this central effect. We evaluated their resistance to hydrolysis by the peptidases of Caco-2 cells and their ability to cross the cell monolayer. To mimic physiological conditions, two preparations of bile salts were used in noncytotoxic concentrations: porcine bile extract and an equimolar mixture of taurocholate, cholate, and deoxycholate. The presence and composition of bile salts appeared to modulate the peptidase activities of the Caco-2 cells involved (i) in the hydrolysis of α-casozepine, leading to much higher formation of fragments f91–99, f91–98, and f91–97, and (ii) in the hydrolysis of f91–97, leading to lower degradation of this peptide. Transport of α-casozepine across Caco-2 monolayer increased significantly, in the presence of bile extract, and of fragment f91–97, in the presence of bile salts.
Milchwissenschaft, 66 (3), pp. 282-285.
Chang, O.K., Lee, B.O., Humbert, G., Saulnier, F.
Biotechnol Prog, 27 (1), pp. 181-190.
Clincke, M.-F., Guedon, E., Yen F.T., Ogier, V., Roitel, O., Goergen, J.-L.
The control of glycosylation to satisfy regulatory requirements and quality consistency of recombinant proteins produced by different processes has become an important issue. With two N-glycosylation sites, γ-interferon (IFN-γ) can be seen as a prototype of a recombinant therapeutic glycoprotein for this purpose. The effect of the nonionic surfactant Pluronic F-68 (PF-68) on cell growth and death was investigated, as well as production and glycosylation of recombinant IFN-γ produced by a CHO cell line that was maintained in a rich protein-free medium in the absence or presence of low agitation. Under these conditions, a dose-dependent effect of PF-68 (0-0.1%) was shown not only to significantly enhance growth but also to reduce cell lysis. Interestingly, supplementing the culture medium with PF-68 led to increased IFN-γ production as a result of both higher cell densities and a higher specific production rate of IFN-γ. If cells were grown with agitation, lack of PF-68 in the culture medium decreased the fraction of the fully glycosylated IFN-γ glycoform (2N) from 80% to 65-70% during the initial period. This effect appeared to be due to a lag phase in cell growth observed during this period. Finally, a global kinetic study of CHO cell metabolism indicated higher efficiency in the utilization of the two major carbon substrates when cultures were supplemented with PF-68. Therefore, these results highlight the importance of understanding how media surfactant can affect cell growth as well as cell death and the product quality of a recombinant glycoprotein expressed in CHO cell cultures.
Trends in Biotechnology, 29 (10), pp. 499-508.
Daniel, C., Roussel, Y., Kleerebezem, M., Pot, B.
The safety status of lactic acid bacteria (LAB) and their capacity to survive the passage through the gastrointestinal tract (GI tract) have rendered them excellent candidates for the production of therapeutic proteins and their delivery in situ to the GI tract. During the past two decades, major health benefits of mucosally administered recombinant LAB have been successfully demonstrated, predominantly using animal models. However, the field has recently moved into the era of human clinical trials. In this review, we provide a timely update on the recent important advances made in this field, and outline the potential of recombinant LAB as therapeutic tools for their safe and efficient use in human health.
Toxicology Letters, 204 (1), pp. 57-63.
Daubie, S., Bisson, J.F., Lalonde, R., Schroeder, H., Rychen, G.
Polybrominated diphenyl ethers (PBDEs) are flame retardants. Because of their high lipophilicity and persistence, PBDEs bioaccumulate in all abiotic and biological matrices. The aim of this study was to investigate the long-term neurobehavioral and physiological effects of exposure to environmental doses of PBDE-99 in adult rats. Rats received a daily administration of PBDE-99 for 90 days by oral gavage at 0.15, 1.5 and 15 µg/kg, doses which are relevant of human exposure. Before and after the 90 days of exposure, behavioral tests including the open-field and the elevated plus-maze tests for locomotor activity and anxiety, and the Morris water maze for spatial learning were conducted. Physiological measures such as body weight, food and water consumption, organs weight, hepatic enzymes levels and PBDE-99 concentration in adipose tissue were also evaluated at the end of exposure. There was no effect on body weight, food and water consumption, organs weight, hepatic enzymes levels despite rising PBDE-99 concentration in adipose tissue with the doses tested. Moreover, there was no effect on locomotor activity and exploration, and spatial learning. Deleterious effects of BDE-99 at high doses have often been highlighted in many studies after an acute dose whereas exposure during 90 days at realistic doses would have no significant effect in adult rats.
Evidence-based Complementary and Alternative Medicine, 2011, art. no. 620862.
Dicko, A., Muanda, F.N., Bouayed, J., Djilani, A., Yao, C., Soulimani, R.
Desmodium adscendens plant is widely used as juice or tea in various parts of the world against a wide range of diseases. This study determines the quality and the quantity of polyphenols, flavonoids, anthocyanins, and tannins in D. adscendens leaves by UV-spectrophotometry and RP-HPLC methods. In addition, the antioxidant capacity of these phenolic compounds is evaluated by ABTS (2, 2 -azino-bis(3-ethylbenzothiazoline-6-sulfonic)), DPPH (2,2'-diphenyl-1 picrylhydrazyl), and Cellular tests. D. adscendens leaves are mainly composite of flavonoid compounds with 12.8mg of catechin equivalent (CE)/g dw. The amounts of total polyphenol compounds are 11.1mg of gallic acid equivalent (GAE)/g dw. The quantity of total anthocyanin and total tannin compounds is not considerable 0.0182mg CgE/g dw and 0.39mg CE/g dw, respectively. A direct correlation between phenolic compounds and antioxidant activity is observed (R2 = 0.96). The RP-HPLC analyses reveal that the main phenolic compound identified in the methanol-water extract is quercetrin dihydrat (2.11mg/mL). According to the results, it is observed that D. adscendens leaves possess a considerable scavenging antioxidant and antiradical capacity, therefore these antioxidant properties might increase the therapeutic value of this medicinal plant.
Comp. Biochem. Physiol. Part A., 159, 92-99
Douxfils J., Mandiki R., Marotte G., Wang N., Silvestre F., Milla S., Henrotte E., Rougeot C., Mélard C., Kestemont, P.
Fish Shellfish Immunol. 31, 1113-21
Douxfils J., Mathieu C., Mandiki SN., Milla S., Henrotte E., Wang N., Vandecan M., Dieu M., Dauchot N., Pigneur LM., Li X., Rougeot C., Mélard C., Silvestre F., Van Doninck K., Raes M., Kestemont P.
Journal of Dairy Science, 94 (6), pp. 2779-2793.
Dufour, D., Germon, P., Brusseaux, E., Le Roux, Y., Dary, A.
Mastitis pathogens belonging to Escherichia coli species are often considered as environmental opportunistic pathogens that invade the udder and are rapidly killed by the immune system of cows. However, several studies have reported that some of these strains are able to persist in the udder for prolonged periods or to adhere and invade mammary epithelial cells, suggesting that they might possess some specific properties or genes that could be involved in their capacity to provoke mastitis. The aim of this work was to search for such specific genes in the E. coli strain P4, which was isolated from a case of severe mastitis and is often used to induce experimental mastitis. We established that this strain belongs to phylogenetic group A of the E. coli species, and that its core genome is very similar to that of the commensal nonpathogenic strain E. coli K-12 MG1655. Seventeen transfer RNA loci, known to be frequently associated with genomic islands, were screened and an altered structure was detected for 7 of them. The partial characterization of 5 of these loci (asnT, leuX, pheV, serU, and thrW) and the complete characterization of 1 (argW) revealed the presence of genomic islands that differ from those already described in pathogenic or nonpathogenic E. coli strains.
Biochem. J., 439 (2), pp. 185-193.
Gaboriaud, C., Gregory-Pauron, L., Teillet, F., Thielens, N.-M., Bally, I., Arlaud, G.-J.
CUB domains are 110-residue protein motifs exhibiting a β-sandwich fold and mediating protein-protein interactions in various extracellular proteins. Recent X-ray structural and mutagenesis studies have led to the identification of a particular CUB domain subset, cbCUB (Ca(2+)-binding CUB domain). Unlike other CUB domains, these harbour a homologous Ca(2+)-binding site that underlies a conserved binding site mediating ionic interaction between two of the three conserved acidic Ca(2+) ligands and a basic (lysine or arginine) residue of a protein ligand, similar to the interactions mediated by the low-density lipoprotein receptor family. cbCUB-mediated protein-ligand interactions usually involve multipoint attachment through several cbCUBs, resulting in high-affinity binding through avidity, despite the low affinity of individual interactions. The aim of the present review is to summarize our current knowledge about the structure and functions of cbCUBs, which represent the majority of the known CUB repertoire and are involved in a variety of major biological functions, including immunity and development, as well as in various cancer types. Examples discussed in the present review include a wide range of soluble and membrane-associated human proteins, as well as some archaeal and invertebrate proteins. The fact that these otherwise unrelated proteins share a common Ca(2+)-dependent ligand-binding ability suggests a mechanism inherited from very primitive ancestors. The information provided in the present review should stimulate further investigations on the crucial interactions mediated by cbCUB-containing proteins.
Developmental Psychobiology, 53 (3), pp. 303-316.
Gelhaye, M., Padzys, G.S., Olry, J.C., Thornton, S.N., Martrette, J.M., Trabalon, M.
Chemical Research in Toxicology, 24 (10), pp. 1653-1667.
Grova, N., Salquèbre, G., Schroeder, H., Appenzeller, B.M.R.
An efficient and selective method for the quantitative determination of polycyclic aromatic hydrocarbons (PAHs) and their monohydroxylated metabolites (OH-PAHs) in rat brain tissue using gas chromatography tandem (triple quadrupole) mass spectrometry (GC–MS/MS) was developed and validated. The list of molecules investigated comprised the 16 PAHs from the US-EPA list and 53 of their OH-PAHs. Brain extract was submitted to enzymatic hydrolysis, followed by liquid–liquid extraction, and then purified by solid-phase extraction. Limits of quantification ranged from 0.6 to 29 pg/mg and from 0.5 to 30 pg/mg for PAHs and OH-PAHs respectively. The analysis of rat brain samples exposed to PAH mixture (0.01–1 mg/kg, 28 days, ip) demonstrated that this method allowed the detection of 16 PAHs and 28 OH-PAHs out of the 69 analytes investigated. Mean concentrations of PAHs in animal brain samples exposed to 1 mg/kg of PAH mixture ranged from 3.0 ± 2 pg/mg for benzo[b]fluoranthene to 146 ± 29 pg/mg for phenanthrene. Concomitantly, mean concentrations of OH-PAHs ranged from 0.49 ± 0.4 to 26.5 ± 23 pg/mg for 2-OH-chrysene and 1-OH-pyrene respectively. This study proves, for the first time, the bioavailability of most of the PAHs and OH-PAHs in mammalian brain tissue and should provide an important new tool for future neurotoxicological studies.
Environmental Toxicology and Chemistry, 30 (6), pp. 1346-1353.
Guiavarc'h, Y., Chahin, A., Dziurla, M.A., Yen, F., Jondreville, C., Rychen G.
Nat. Struct. Mol. Biol., 18 (8), pp. 915-919.
Guillet, V., Knibiehler, M., Gregory-Pauron, L., Remy, M.-H., Chemin, C., Raynaud-Messina, B., Bon, C., Kollman, J.-M., Agard, D.-A., Merdes, A., Mourey, L.
Microtubule nucleation in all eukaryotes involves γ-tubulin small complexes (γTuSCs) that comprise two molecules of γ-tubulin bound to γ-tubulin complex proteins (GCPs) GCP2 and GCP3. In many eukaryotes, multiple γTuSCs associate with GCP4, GCP5 and GCP6 into large γ-tubulin ring complexes (γTuRCs). Recent cryo-EM studies indicate that a scaffold similar to γTuRCs is formed by lateral association of γTuSCs, with the C-terminal regions of GCP2 and GCP3 binding γ-tubulin molecules. However, the exact role of GCPs in microtubule nucleation remains unknown. Here we report the crystal structure of human GCP4 and show that its C-terminal domain binds directly to γ-tubulin. The human GCP4 structure is the prototype for all GCPs, as it can be precisely positioned within the γTuSC envelope, revealing the nature of protein-protein interactions and conformational changes regulating nucleation activity.
Ecotoxicology and Environmental Safety, 76: 56-62.
Hatef A., Alavi S.M.H., Abdulfatah A., Fontaine P., Rodina M., Linhart O.
Lipids, 46, 179-187.
Henrotte E., Milla S., Mandiki R., Kestemont P.
PLoS One, 6 (1), e16106.
Hirrlinger, P.G., Pannicke, T., Winkler, U., Claudepierre, T., Varshney, S., Schulze, C., Reichenbach, A., Brunken, W.J., Hirrlinger, J.
Glial cells such as retinal Müller glial cells are involved in potassium ion and water homeostasis of the neural tissue. In these cells, inwardly rectifying potassium (Kir) channels and aquaporin-4 water channels play an important role in the process of spatial potassium buffering and water drainage. Moreover, Kir4.1 channels are involved in the maintenance of the negative Müller cell membrane potential. The subcellular distribution of Kir4.1 and aquaporin-4 channels appears to be maintained by interactions with extracellular and intracellular molecules. Laminins in the extracellular matrix, dystroglycan in the membrane, and dystrophins in the cytomatrix form a complex mediating the polarized expression of Kir4.1 and aquaporin-4 in Müller cells.
The aim of the present study was to test the function of the β2 and γ3 containing laminins in murine Müller cells. We used knockout mice with genetic deletion of both β2 and γ3 laminin genes to assay the effects on Kir4.1 and aquaporin-4. We studied protein and mRNA expression by immunohistochemistry, Western Blot, and quantitative RT-PCR, respectively, and membrane currents of isolated cells by patch-clamp experiments. We found a down-regulation of mRNA and protein of Kir4.1 as well as of aquaporin-4 protein in laminin knockout mice. Moreover, Müller cells from laminin β2 and γ3 knockout mice had reduced Kir-mediated inward currents and their membrane potentials were more positive than those in age-matched wild-type mice.
These findings demonstrate a strong impact of laminin β2 and γ3 subunits on the expression and function of both aquaporin-4 and Kir4.1, two important membrane proteins in Müller cells.
J. Endocrinol., 209, 221-235.
Kiilerich P., Milla S., Sturm A., Chevolleau S., Giton F., Terrien X., Fiet J., Prunet P.
Journal of Environmental Protection, 2 (1), pp. 90-96.
Konuspayeva, G., Jurjanz, S., Loiseau, G., Barci, V., Akhmetsadykova, S., Meldebekova, A.A., Faye, B.
In Kazakhstan, camel breeding mainly occupies areas sometimes close to polluting industries or other sources of pollu- tion as industrial agriculture, mainly cotton. Products issued from camel farms close to these sources as camel raw milk and fermented milk (shubat), wool and meat, traditionally used by humans could be contaminated. We investigated camel raw milk and fermented milk for the content of heavy metals (lead, cadmium, zinc and copper), radionuclide and some organic pollutants (PAHs, pesticides and indicator PCBs) in samples from different regions with a priori high risk of pollution (Atyrau, Kyzylorda, South-Kazakhstan and Almaty region). In the present paper, only some milk samples presented high lead concentration (> 500 ppb). After analysis for organic pollutants, it was observed some traces of hexachlorocyclohexane, lindane, hexanchlorothalonil in milk samples from different regions. One sample was also slightly contaminated with radionuclide. These preliminary results allow establishing a first map of risk for camel farming. As the whole, South-Kazakhstan appeared the most exposed region.
Talanta, 85 (3), pp. 1500-1507.
Lazartigues, A., Fratta, C., Baudot, R., Wiest, L., Feidt, C., Thomas, M., Cren-Olive, C.
Pesticides residues in aquatic ecosystems are an environmental concern which requires efficient analytical methods. In this study, we proposed a generic method for the quantification of 13 pesticides (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl) in three environmental matrices. Pesticides from water were extracted using a solid phase extraction system and a single solid-liquid extraction method was optimized for sediment and fish muscle, followed by a unique analysis by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Limits of quantification were below 5 ng L(-1) for water (except for fluroxypyr and iprodion) and ranged between 0.1 ng g(-1) and 57.7 ng g(-1) for sediments and regarding fish, were below 1 ng g(-1) for 8 molecules and were determined between 5 and 49 ng g(-1) for the 5 other compounds. This method was finally used as a new routine practice for environmental research.
Chemosphere, 84 (10), pp. 1489-1494.
Lazartigues, A., Thomas, M., Grandclaudon, C., Brun-Bellut, J., Feidt, C.
Eurasian perch (Perca fluviatilis) was exposed trophically to phenanthrene, pyrene and benzo[a]pyrene. Accumulation kinetics in the muscle tissue of parent PAHs and hydroxylated metabolites were established for 56. days at 3 levels of exposure (0, 100 and 500μg/kg BW). Benzo[a]pyrene and 3-hydroxy-benzo[a]pyrene were not detected in the muscles. During exposure, there was an increase in phenanthrene, pyrene and their hydroxylated metabolites in the muscle tissue. Low transfer to muscle tissue was observed at equilibrium for phenanthrene (4.4 ± 0.6% and 2.7 ± 0.8%) and pyrene (1.0 ± 0.2% and 0.33 ± 0.09%), depending on the concentrations in the spiked feed.
Analytical and Bioanalytical Chemsitry, 400 (7), pp. 2185-2193.
Lazartigues, A., Wiest, L., Baudot, R., Thomas, M., Feidt, C., Cren-Olive, C.
Pesticide residues in fish muscle are an environmental and a health safety concern which requires analytical methods presenting high sensitivity and low limits of quantification. In this study, adapted QuEChERS method, coupled to liquid chromatography tandem mass spectrometry (Scheduled MRM-5500 QTRAP), was developed to quantify 13 pesticides (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl) in muscle of fish. Quantification limits were below 1 ng g(-1) except for clomazone (1.8 ng g(-1)) and quizalofop (7.4 ng g(-1)). Best recoveries were observed for perch (> 80%) and roach (> 68%), except for thifensulfuron-methyl. Lower recoveries had been observed for carp (6% to 86%). Relative standard deviation was lower than 28% for intra-day and 29% for inter-day analysis, respectively. This method was successfully tested on three fish species, naturally or orally exposed: roach (Rutilus rutilus), perch (Perca fluviatilis) and carp (Cyprinus carpio). Few levels were observed in fish naturally exposed, but carp and perch orally contaminated showed measurable levels in their muscles.
Systematic Entomology, 36 (3), pp. 453-469.
Lecocq, T., Lhomme, P., Michez, D., Dellicour, S., Valterová, I., Rasmont, P.
Many methods, based on morphological, molecular or chemical characters, have been used to address the question of species taxonomic status. Integrative taxonomy aims to define stronger supported taxonomic hypotheses by considering complementary datasets from different characters. By following an integrative approach, the present study includes molecular, chemical and morphological criteria to establish the taxonomic status of two rare and doubtful cuckoo bumblebee taxa: Bombus (Psithyrus) barbutellus and Bombus (Psithyrus) maxillosus. These two sympatric taxa are discriminated by few morphological criteria (mainly wing darkness and hair length). We used these morphological character diagnoses to establish an a priori status of our samples (23 specimens). We developed a combined molecular dataset from one nuclear gene, elongation factor 1? (EF-1?), and one mitochondrial gene, cytochrome c oxidase subunit I (COI ), spanning 1623 bp, and a chemical dataset of sexual marking pheromones (73 compounds). The molecular data were subjected to maximum-likelihood and Bayesian phylogenetic inference under partitioned model and maximum parsimony. The chemical data were analysed by clustering and the two-group k-means method to test divergences between the two species. The resulting phylogenetic trees show no consistent divergence between the two taxa. Moreover, we found no divergence in the sexual marking pheromones in the clustering and two-group k-means analyses. These converging results support the conspecificity of both taxa. Nonetheless, our determinations using the traditional morphological criteria separated our samples into two taxa. We conclude that the morphological criteria seem to relate to intraspecific variations: B. maxillosus is regarded as a syn.n. of B. barbutellus.
Journal of Animal Science, 89 (11), pp. 3596-3611.
Letourneau-Montminy, M. P., Narcy, A., Lescoat, P., Magnin, M., Bernier, J. F., Sauvant, D., Jondreville, C., Pomar, C.
Environmental effects of excess P from manure and the soaring price of
phosphates are major issues in pig production. To optimize P
utilization, it is crucial to improve our capacity to predict the amount
of P absorbed, while taking into account the main factors of variation.
Mathematical modeling can represent the complexity of the processes and
interactions in determining the digestive utilization of P in growing
pigs. This paper describes and evaluates a model developed to simulate
the fate of the dietary forms of P in the digestive tract of growing
pigs, with particular emphasis on the effect of dietary Ca and exogenous
phytase on P digestive utilization. The model consists of 3 compartments
associated with specific anatomical sections: stomach, proximal small
intestine, and distal small intestine. The main metabolic processes
occurring in these sections are, respectively, P
solubilization/insolubilization and phytate P hydrolysis, and P
absorption and P insolubilization. Model parameters governing these
flows were derived from in vitro and in vivo literature data. The
sensitivity analysis revealed that the model was stable within a large
range of model parameter values (+/- 1.5 SD). The model was able to
predict the efficacy of Aspergillus niger microbial phytase in
accordance with literature values, as well as the decreased efficacy of
plant phytase compared with microbial phytase. The prediction
capabilities of the model were assessed by comparing actual and
simulated P and Ca apparent total-tract digestibility (ATTD) based on
published pig data not used for model development. Prediction of P
digestibility across 66 experiments and 281 observations was adequate [P
ATTD observed = 0.24 (SE, 0.943) + 0.98 (SE, 0.0196) x P ATTD predicted;
R(2), 0.90; disturbance error (ED), 96.5%], whereas prediction of Ca
digestibility across 47 experiments and 193 observations was less
accurate (Ca ATTD observed = 11.1 + 0.75 x Ca ATTD predicted; R(2),
0.78; ED, 20.4%). A lack of agreement between experimental and simulated
Ca digestibility was found. This model is, therefore, useful in
evaluating P digestibility for different feedstuffs and feeding
strategies. It can also be used to provide insight for improving dietary
P utilization, especially from plant sources, by quantifying the effect
of the mean sources of variation affecting P utilization.
Aquac. Res., 42, 693-703
Mandiki R., Milla S., Wang N., Blanchard G., Djonkack T., Tanascaux S., Kestemont P.
Journal of Dairy Science, 94 (11), pp. 5369-5374.
Martí-De Olives, A., Le Roux, Y., Rubert-Alemán J., Peris, C., Molina, M.P.
The aim of this work was to evaluate the effect of intramammary infection (IMI) on the endogenous proteolysis of milk. Four control checks were carried out in the half-udder milk of 10 ewes that acquired unilateral subclinical mastitis. Two of these checks were conducted before the infection was established and 2 after. Ten healthy ewes were tested as a control group. The presence of a subclinical IMI involved an increase of the products of casein hydrolysis, the proteose-peptone (p-p) fraction and minor (m) caseins, and a decrease of β-casein. As a result, a significant increase in the proteolysis index (PI), calculated as the ratio of m-casein to the sum of caseins (α + β + κ), took place. α-Casein and κ-casein were not significantly affected by IMI. Correlations confirmed the scenario: log10 of somatic cell count (SCC) was positively correlated with p-p content and negatively with β-casein, whereas log10 SCC was not correlated with α-casein or κ-casein. On the other hand, p-p content was positively correlated with m-casein and PI and negatively with β-casein, but no correlation was detected between p-p content and α- or κ-casein. Furthermore, between casein fractions, m-casein was only significantly correlated with β-casein. These results suggest that use of indices of proteolysis of caseins such as p-p, m-casein, and PI, could be applied together with SCC to evaluate the cheese-making quality of milk.
Ecotoxicology, 20, 305-319
Milla S., Depiereux S., Kestemont P.
Aqua. Res., 42, 1061-1065.
Milla S., Sambroni E., Kestemont P., Jalabert B.
International Dairy Journal, 21 (4), pp. 214-221.
Sadat, L., Cakir-Kiefer, C., N’Negue, M.-A., Gaillard, J.-L., Girardet, J.-M., Miclo, L.
The second main bovine whey protein, α-lactalbumin, was hydrolyzed by thermolysin at 70 °C, i.e., in a molten-globule conformational state susceptible to enzyme attack, for production of small peptides with potential antioxidative properties. The main thermolytic fragments were then purified by reversed-phase liquid chromatography and identified by mass spectrometry. Antioxidant activities of the protein, its thermolytic hydrolyzate, and pure peptides were evaluated using 2,2′-azinobis[3-ethylbenzothiazoline-6-sulfonate] (ABTS+) radical-scavenging activity. The whole protein and its hydrolyzate exhibited antioxidant activities comparable with that of Trolox, a vitamin E analog. Among the thermolytic fragments, five peptides, all containing at least one Tyr or Trp residue located at one of the extremities of the sequence, displayed the most efficient antioxidant activities. In particular, Ile101-Asn-Tyr-Trp104 and Leu115-Asp-Gln-Trp118 possessed remarkable radical-scavenging capacity, 5-fold and 10-fold higher, respectively, than those of gallic acid and Trolox tested under the same experimental conditions.
International Journal of Food Microbiology, 146 (1), pp. 1-13.
Sadat-Mekmene, L., Genay, M., Atlan, D., Lortal, S., Gagnaire, V.
Lactobacillus helveticus is a lactic acid bacterium very used in fermented milks and cheese. The rapid growth of L. helveticus in milk is supported by an efficient cell envelope proteinase (CEP) activity, due to subtilisin-like serine proteases. These enzymes play also crucial roles in texture and flavor formation in dairy products as well as in generating in situ bioactive peptides. In L. helveticus, several genes encoding putative CEPs were detected and characterized by a large intraspecific diversity; little is known about regulation of expression of CEP-encoding genes. Anchored at the bacterial surface, CEPs are large-sized enzymes (>150kDa) hydrolyzing β- and α(s1)-casein as well. Substrate cleavages occur after almost all types of amino acids residues, but mass spectrometry analysis revealed L. helveticus strains with specific profiles of substrate hydrolysis, which could explain identification of strains associated with interesting technological properties. In this review, the most recent data regarding CEP-encoding genes, CEP activities toward caseins and L. helveticus strain diversity are discussed.
Critical Reviews in Environmental Science and Technology, 41 (22), pp. 2026-2047.
Schroeder, H.
Because the developing brain is highly susceptible to toxic injuries, the effects of early exposure to air pollutants such as polycyclic aromatic hydrocarbons have to be questioned. In addition to direct inhalation, food consumption appears to be the main source of intake for these pollutants in humans. Thus, a risk does exist for newborns and young infants through ingestion of contaminated milk from their mothers or commercial ruminant preparations at a moment of extreme vulnerability for the brain. The author reviews human and animal studies, which provide some evidence of the potent toxicity of polycyclic aromatic hydrocarbons for the developing brain.
Aquaculture Research 42: 630-654
Teletchea, F., Fontaine, P.
Aquaculture 316 : 104-110
Trabelsi, A., Gardeur, J.-N., Teletchea, F., Fontaine, P.
Adv. Funct. Mater., 21 (22), pp. 4202.
Wittmer, C.R., Claudepierre, T., Reber, M., Wiedemann, P., Garlick, J.A., Kaplan, D., Egles, C.
The repair of central nerves remains a major challenge in regenerative neurobiology. Regenerative guides possessing critical features such as cell adhesion, physical guiding and topical stimulation are needed. To generate such a guide, silk protein materials are prepared using electrospinning. The silk is selected for this study due to its biocompatibility and ability to be electrospun for the formation of aligned biofunctional nanofibers. The addition of Brain Derived Neurotrophic Factor (BDNF), Ciliary Neurotrophic Factor (CNTF) or both to the electrospun fibers enable enhanced function without impact to the structure or the surface morphology. Only a small fraction of the loaded growth factors is released over time allowing the fibers to continue to provide these factors to the cells for extended periods of time. The entrapped factors remain active and available to the cells as rat retinal ganglion cells (RGCs) exhibit longer axonal growth when in contact with the biofunctionalized fibers. Compare to non-functionalized fibers, the growth of neurites increased 2 fold on fibers containing BDNF, 2.5 fold with fibers containing CNTF and by almost 3-fold on fibers containing both factors. The results demonstrate the potential of aligned and functionalized electrospun silk fibers to promote nerve growth in the central nervous system, underlying the great potential of complex biomaterials in neuroregenerative strategies following axotomy and nerve crush traumas.
Alter Agri, 105, pp. 16-18.
Jurjanz, S., Jondreville, C.
Phytotherapie, 9 (1), pp. 2-6.
Kambouche, N., Merah, B., Derdour, A., Bellahouel, S., Younos, C., Soulimani, R.
ß-sitoglucoside saponin was separated from Anabasis articulata: plant used in traditional medicine for treatment of diabetes (Chenopodiaceae). Different methods and spectroscopic chromatography have allowed to identify the product isolated. Experiments were performed in non-diabetic mice, and in diabetic mice (glucose treated mice) showed that oral administration of the butanolic extract (saponins) 10 mg/kg decreased the glycaemia to 20.09% (P < 0.05), six hours after administration. These results also showed that oral administration of 4 mg/kg of ß-Sitoglucoside decrease the glycaemia to 24.2% (P < 0.05) after six hours of treatment and corresponding to the greatest reduction in diabetic mice (anti-hyperglycemic effect) similar to the antidiabetic action of reference molecule: glibenclamide (10 mg/kg). This dose has been able to restore the blood glucose level in diabetic mice, whereas the concentration of 2 mg/kg had no appreciable effect. This study confirms the effect of the antidiabetic compound separated.
Bulletin de Veille Scientifique de l'ANSES, 12, pp. 91-98.
Schroeder, H.
Bulletin de Veille Scientifique de l'ANSES, 13, pp. 85-92.
Schroeder, H.
Bulletin de Veille Scientifique de l'ANSES, 14, pp. 73-78.
Schroeder, H.
Bulletin de Veille Scientifique de l'ANSES, 15, pp. 97-102.
Schroeder, H.
Algerian Journal of Arid Environment, 1 (1), pp. 28-36.
Tankari dan-badjo, A., Yadji, G., Dan lamso, N., Ducoulombier, C., Feidt, C., Sterckman, T., Echevarria, G., Rychen, G.
Indian Journal of Science and Technology, 4 (8), pp. 313-314.
Teletchea, F., Fontaine, P.
Copper mobilization affected by weather conditions in a stormwater detention system receiving runoff waters from vineyard soils (Champagne, France).
Environmental Pollution, 158 (2), pp. 476-482.
Banas, D., Marin, B., Skraber, S., Chopin, E.I.B., Zanella, A.
Copper, a priority substance on the EU-Water Framework Directive list, is widely used to protect grapevines against fungus diseases. Many vineyards being located on steep slopes, large amounts of Cu could be discharged in downstream systems by runoff water. The efficiency of stormwater detention basins to retain copper in a vineyard catchment was estimated. Suspended solids, dissolved (Cudiss) and total Cu (Cutot) concentrations were monitored in runoff water, upstream, into and downstream from a detention pond. Mean Cutot concentrations in entering water was 53.6 μg/L whereas it never exceeded 2.4 μg/L in seepage. Cutot concentrations in basin water (>100 μg/L in 24% of the samples) exceeded LC50 values for several aquatic animals. Copper was principally sequestered by reduced compounds in the basin sediments (2/3 of Cutot). Metal sequestration was reversible since sediment resuspension resulted in Cu remobilization. Wind velocity controlled resuspension, explained 70% of Cudiss variability and could help predicting Cu mobilization.
Current Nutrition and Food Science, 6 (1), pp. 13-18.
Bouayed, J.
Oxidative Medicine & Cellular Longevity, 3 (4), pp. 63–67.
Bouayed, J., Bohn, T.
Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering, 45 (10), pp. 1264-1274.
Caboche, J., Denys, S., Feidt, C., Delalain, P., Tack, K., Rychen, G.
This investigation was undertaken to identify the most significant parameters that can be used to model the bioaccessibility of lead in contaminated soils. Twenty-five soil samples contaminated by two distinct sources of contamination (mining and smelting areas) were investigated in this work. Edaphic soil properties were determined using the classic techniques. Speciation and solid phase distribution of Pb were determined by sequential fractionation and physical analysis (XRD and SEM-EDX). Bioaccessibility of Pb was measured using the unified BARGE protocol on each soil samples and each residue following the different steps of the sequential extraction procedure. Results showed that Pb speciation varied according to the source of contamination. Pb gastric bioaccessibility ranged from 12% to 86% in mining soils and from 40% to 95% in smelting soils. Soil edaphic properties (pH, CEC, clays content or organic matter content) cannot be used to model Pb bioaccessibility as these parameters could not be extrapolated from on site to another. The differences in Pb bioaccessibility between the 25 soils were better reflected by the nature of the Pb-bearing minerals as characterized by sequential extractions. Soluble, exchangeable and acid-soluble phases could explain from 70 to 98% of Pb bioaccessibility. Consequently, Pb bioaccessibility is extremely sensitive to the Pb-bearing phase distribution. This distribution should be thoroughly evaluated before applying any remedial techniques that would potentially affect Pb speciation in soils.
Agronomy for Sustainable Development, 30 (4), pp. 769-775.
Costera, A., Rychen, G., Feidt, C., Soligot, C., Jurjanz, S.
Airborne polycyclic aromatic hydrocarbons (PAHs) are deposited on agricultural grasses. In turn, PAHs enter the food chain through animals eating grasses. However, the risk of food contamination, e.g. of milk, is unknown because mechanisms ruling the fate of PAHs during digestion by cows are not understood, especially in the rumen. Here, we studied the disappearance rate of phenanthrene, pyrene and benzo[a]pyrene, n-alkanes, and dry matter from contaminated grass samples in the rumen, the first compartment of the ruminant digestive tract. Three cows fitted with a rumen cannula were used for this study and the grass samples were incubated in sacco for 1, 3, 6, 12, 24 and 48 h. The results show that the disappearance rate of PAHs was fast and higher than that of n-alkanes. On average, 83% of PAHs disappeared after 1 h of incubation. Phenanthrene showed a disappearance rate higher than 90%. The findings suggest a fast desorption of PAHs from the surface of the grass leaves. The digestive hydrolysis of the grass is not required to release PAHs, contrary to other fractions. As a consequence, the bioavailability of PAHs is not limited by the grass.
Chemosphere, 78 (8), pp. 1004-1010.
Fournier, A., Feidt, C., Dziurla, M.A., Grandclaudon, C., Jondreville, C.
The kinetic of transfer into egg yolk of Persistent Organic Pollutants with contrasting properties regarding biotransformation and bioaccumulation was investigated. Twenty-four Hy line hens, aged 26 weeks, were orally administered, during 1 or 3 consecutive days, 6 mg of a mixture of three PAHs (phenanthrene, pyrene, benzo[a]pyrene) in equal amounts (w:w) or 3 mg of lindane per kg body weight daily. Each day, contaminants were administered 1 h after oviposition in one gelatin capsule. Eggs were collected daily during the 12 d following the first dosing. Concentrations of PAHs and their main hydroxylated metabolites in yolk were determined using HPLC coupled with fluorimetric detection, while lindane was analysed by GC-ED. At the end of the experiment, hens were sacrified and preovulatory yolks were collected and weighed. All three PAHs were recovered in yolks, mainly as metabolites, indicating an active biotransformation of these compounds in hens. Within 10 d, PAHs and metabolites concentrations in yolks were back to initial values. However, the recovery rate of these compounds to yolk calculated over the 12-d experiment, was very low, reaching 0.089%, 0.034% and 0.006% for Phe, Pyr and B[a]P, respectively. Daily deposition of yolk and of PAHs and metabolites were found to be directly proportional, indicating that no significant body storage of these PAHs occurred and that they were rapidly hydroxylated after ingestion. In contrast, lindane and yolk deposition could not be related. Storage of lindane in body fat explains its slower elimination via eggs.
Small Ruminant Research, 91 (2-3), pp. 141-152.
Guiavarc'h, Y.P., Chahin, A., Dziurla, M.-A., Toussaint, H., Feidt, C., Rychen, G.
Despite its interest, little is known about the potential of 1-hydroxypyrene to be used as biomarker of exposure of dairy ruminants (goat, sheep and cow) to pyrene or other polycyclic aromatic hydrocarbons (PAHs) and, to date, no clear approach has been proposed to evaluate and use this biomarking potential for evaluating exposure to pyrene and other polycyclic aromatic hydrocarbons also prone to contaminate the vegetal cover ingested by these dairy ruminants. In the present study, three Alpin goats were daily submitted to two different levels (0.04 and 0.28 mg/day) of pyrene oral ingestion, together with phenanthrene and benzo(a)pyrene, during 1 week each. Extraction and HPLC-fluorimetry analysis results on 1-hydroxypyrene in milk and urine as well as on 1, 2, 3 and 4-OH-phenanthrene and 3-OH benzo(a)pyrene in urine were fruitfully combined with few recently published results on 1-hydroxypyrene excretion achieved in a former and similar experiment performed on a set of four goats with doses 1, 7 and 49 mg/day/goat. Statistical analysis demonstrated the biomarking potential of 1-hydroxypyrene to be used for evaluation of oral exposure to pyrene under low and large levels of exposure and transfer (linear) equations were proposed. Finally, a literature based approach, combined with the achieved experimental transfer rates, was proposed for evaluating the amounts of 12 additional polycyclic aromatic hydrocarbons into the fodder, thus extending the potential of 1-hydroxypyrene in urine and/or milk to be used as a biomarker of oral exposure to PAHs. Keeping in mind that milk is much easier to sample as compared to urine, such approach may be used as a first step for evaluation of oral exposure of goat and likely other dairy ruminants to polycyclic aromatic hydrocarbons prior to any exhaustive, time and cost consuming analytical investigation.
Productions Animales, 23(2), pp. 205-214.
Jondreville, C., Fournier, A., Travel, A., Feidt, C., Roudaut, B.
Polycyclic Aromatic Compounds, 30 (3), pp. 141-152.
Lazartigues, A., Thomas, M., Brun-Bellut, J., Feidt, C.
This study aimed to determine the incorporation of PAHs into muscle of Cyprinus carpio. Three model compounds (phenanthrene, pyrene and benzo[a]pyrene) were orally administered during 56 days, in a series of three increasing doses (0, 100, 500 μg of each PAHs per kg of fish). PAHs and their hydroxylated metabolites were analyzed by a HPLC-Fluorimetry method. Results of this study showed a significant increase of phenanthrene and pyrene in muscle. Benzo[a]pyrene incorporation to muscle was not effective. Concerning hydroxylated metabolites, they were not detected in muscle of carp. Steady states for phenanthrene and pyrene were obtained after 28 days of exposure. Low incorporation to muscle was observed at equilibrium for phenanthrene (6% and 3%) and pyrene (3% and 1%), depending of the dose tested.
Animal, 4 (11), pp. 1844-1853.
Létourneau-Montminy, M.P., Narcy, A., Lescoat, P., Bernier, J.F., Magnin, M., Pomar, C., Nys, Y., Sauvant, D., Jondreville, C.
Pollution relative to phosphorus excretion in poultry manure as well as the soaring prices of phosphate, a non-renewable resource, remain of major importance. Thus, a good understanding of bird response regarding dietary phosphorus (P) is a prerequisite to optimise the utilisation of this essential element in broiler diets. A database built from 15 experiments with 203 treatments was used to predict the response of 21-day-old broilers to dietary non-phytate P (NPP), taking into account the main factors of variation, calcium (Ca) and microbial phytase derived from Aspergillus niger, in terms of average daily feed intake (ADFI), average daily gain (ADG), gain to feed (G:F) and tibia ash concentration. All criteria evolve linearly (P < 0.001) and quadratically (P < 0.001) with dietary NPP concentration. Dietary Ca affected the intercept and linear component for ADG (P < 0.01), G:F (P < 0.05) and tibia ash concentration (P < 0.001), whereas for ADFI, it affected only the intercept (P < 0.01). Microbial phytase addition impacted on the intercept, the linear and the quadratic coefficient for ADFI (P < 0.01), ADG (P < 0.001) and G:F (P < 0.05), and on the intercept and the linear component (P < 0.001) for tibia ash concentration. An evaluation of these models was then performed on a database built from 28 experiments and 255 treatments that were not used to perform the models. Results showed that ADFI, ADG and Tibia ash concentration were predicted fairly well (slope and intercept did not deviate from 0 to 1, respectively), whereas this was not the case for G:F. The increase in dietary Ca concentration aggravated P deficiency for all criteria while phytase addition had a positive effect. The more P deficiency was marked, the more the bird response to ADFI, ADG, G:F and tibia ash concentration was exacerbated. It must also be considered that even if the decrease in dietary Ca may improve P utilisation, it could in turn become limiting for bone mineralisation. In conclusion, this meta-analysis provides ways to reduce dietary P in broiler diets without impairing performance, taking into account dietary Ca and microbial phytase.
Journal of Animal Science, 88 (5), pp. 1706-1717.
Létourneau-Montminy, M.P., Narcy, A., Magnin, M., Sauvant, D., Bernier, J.F., Pomar, C., Jondreville, C.
The present study was conducted to assess the effect of 2 dietary Ca concentrations on P and Ca digestive and metabolic utilization in weanling pigs fed diets providing practical concentrations of P, with or without phytase. The responses of pigs fed diets adequate or moderately deficient in Ca and P postweaning were compared. A total of 60 pigs weaned at 28 d of age were used. Two groups of 30 pigs with differing mineral status resulted from a 10-d depletion period, during which the animals received depletion diets (DD) that consisted of corn-soybean meal with either 1.42% Ca and 0.80% P (DD+) or 0.67% Ca and 0.43% P (DD-), designed to achieve the same Ca:digestible P ratio. At the end of the depletion period, a plasma sample was taken from each pig and 12 pigs (6 from each group) were slaughtered for bone assessment to establish the baseline mineral status. The animals fed the DD-diet had signs of P deficiency with reduced plasma P (13%; P < 0.01) and femur ash concentration (8%; P < 0.05), and increased plasma Ca (9%; P < 0.05) and alkaline phosphatase activity (31%; P < 0.01). For the subsequent 25-d period, the remaining 24 pigs from each group were fed 1 of 4 repletion diets: 1) 0.56% P, 1.06% Ca; 2) 0.56% P, 0.67% Ca; 3) diet 1 + 1,000 phytase units (FTU) of Natuphos phytase/kg; and 4) diet 2 + 1,000 FTU of Natuphos phytase/kg. Total feces and urine were collected from d 5 to 11, and a blood sample was taken from each pig at d 11 and 25. The initial moderate P deficiency (DD-) stimulated Ca absorption (5%; P < 0.01), irrespective of the repletion diet, and stimulated P absorption (5%; DD × phytase, P < 0.05), only when the diets contained phytase. At the end of the repletion period, because of these compensatory phenomena, the depleted pigs achieved full recovery of femur DM and ash weight when they received phytase, whereas ash concentration tended to remain reduced by 3% (P = 0.08). Phosphorus digestibility was improved in the diets supplemented with phytase (73.0 vs. 56.0%; P < 0.001), whereas an increase in dietary Ca decreased P digestibility (65.6 vs. 63.4%; P < 0.05). Those 2 effects were independent, indicating that dietary Ca reduced equally P digestibility with and without phytase and did not influence the efficiency of phytase in releasing P in the digestive tract. In pigs fed diets with phytase, however, the reduction of Ca (Ca:P from 1.9 to 1.3) increased urinary P losses 5-fold. Those extra losses were due to a lack of Ca for skeleton ash deposition, resulting in a 4% reduction in femur ash concentration. In the end, reducing the dietary Ca:P from 1.9 to 1.3 in a practical diet containing 0.56% P did not improve the efficiency of phytase in releasing P. Moreover, the reduction in dietary Ca (Ca:P) caused an imbalance between Ca and P that impaired bone mineralization.
Rapid Communications in Mass Spectrometry, 24 (11) pp. 1533-1542.
Matéos, A., Girardet, J.-M., Mollé, D., Corbier, C., Gaillard, J.-L., Miclo, L.
Equine beta-casein is phosphorylated at variable degrees and isoforms carrying 3 to 7 phosphate groups (3P–7P) have been found in milk, but the phosphorylated amino acid residues of each isoform are not yet identified. In the present work, the different phosphorylation variants were first isolated by ionexchange chromatography and then hydrolysed by trypsin to generate caseinophosphopeptides (CPPs), each containing all the potential phosphorylation sites. The equine CPPs were prepared by metal oxide affinity chromatography, a method based on the affinity of phosphate groups towards titanium dioxide immobilized onto a micro-column. This method turned out to be an efficient tool to separate the CPPs Arg1–Lys34 and Glu4–Lys34 from non-phosphorylated peptides. Purification was achieved by reversed-phase high-performance liquid chromatography (RP-HPLC) and each CPP was hydrolyzed by endoproteinase Glu-C. Finally, the digests were analyzed by RP-HPLC/electrospray ionization mass spectrometry (RP-HPLC/ESI-MS) and identified by nano-electrospray ionization tandem mass spectrometry (nESI-MS/MS) to locate the phosphorylated sites of the beta-casein isoforms 4P–7P with accuracy. Thus, the isoform 4P was found to be phosphorylated on residues Ser9, Ser23, Ser24, and Ser25. Addition of phosphate groups on Ser18, Thr12, and Ser10 led to the formation of the isoforms 5P–7P, respectively. The results indicated that the in vivo phosphorylation of the equine beta-casein follows a sequential way and is not randomly performed.
Fish Shellfish Immunol. 28, 931-941.
Milla S., Wang N., Mandiki R., Nadzialek S., Kestemont P.
Numerical modelling of vertical suspended solids concentrations and irradiance in a turbid shallow system (Vaccares, France).
Hydrobiologia, 638, pp.161-179.
Millet, B., Robert, C., Grillas, P., Coughlan, C., Banas, D.
In shallow ecosystems, the short temporal variability of available underwater irradiance is considered a major process controlling submerged macrophytes development. Mechanistic models that estimate photosynthetically available radiation (PAR) in shallow ecosystems at very short time scales are needed for use in predicting submerged macrophyte growth and persistence. We coupled a 2D horizontal circulation model with, first, a 1D vertical numerical model of suspended solid (SS) re-suspension, diffusion and settling, and next, with a model of vertical extinction of irradiance, previously validated at the same site. The study site was the Vaccarès lagoon (France) where a large data set of high frequency bottom irradiance and SS concentration were available. SS and irradiance measurements were conducted at a vertical study station, monitored over a 6 month period (from December 1995 to May 1996) characterized by wide-ranging wind velocities (1.5-18 ms-1). In addition, grain-size analyses conducted over the whole lagoon, allowed adaptation of the 1D numerical model to the silt-sized (7 μm) and clay-sized (0.3 μm) fractions that prevail in the local sediment. First, model results showed that about 60% of the variance in bottom irradiance time series can be explained by our deterministic formulations, thus representing the same level of efficiency than those already obtained by a stochastic model previously developed with the same data set. Second, model results showed that the fit of the model to the field data (SS concentrations and bottom irradiance) depended mainly on storm occurrence and season (winter or spring). Finally, model results suggested that the underwater irradiance regime was controlled by seasonal succession of the horizontal circulation of turbid water in the lagoon, with increased solids concentrations in winter, followed by submerged canopy development and decreased solids concentrations in spring.
Environmental Science and Technology, 44 (7), pp. 2682-2688.
Ounnas, F., Feidt, C., Toussaint, H., Marchand, P., Bizec, B.L.E., Rychen, G., Jurjanz, S.
This study investigated milk excretion kinetics of PCBs, tetraBDE (BDE 47), and penta-BDE (BDE 99) in goats exposed to contaminated soil under controlled conditions. The animals were fed (80 days) with feed containing 5% of contaminated soil. During this exposure period, milk was analyzed weekly. At the end of the experiment the PCBs and PBDEs retained in hepatic and adipose tissues were also determined. The soilmilk carry over rates (CORs) of PCBs ranged from 6 to 62%. This result suggests that a large part of ingested soil-bound PCBs was recovered in milk. Significantly different levels between the congeners were reported in the tissues (fat, liver). BDE 47 and 99 excretions in milk achieved a plateau after 2 weeks of exposure, and their corresponding CORs were about 30%. These two congeners showed a significantly (P < 0.05) lower accumulation in the adipose tissue than the major PCB congeners. The concentrations of BDE 47 and 99 in the liver were the same as PCB concentrations. This result suggests that the low brominated congeners are submitted to the metabolism more extensively than the major PCBs.
NeuroImmunoModulation, 17 (1), pp. 1-8.
Rammal, H., Bouayed, J., Falla, J., Boujedaini, N., Soulimani, R.
In the present study, we aimed to examine whether a high anxiety level affects various parameters of immunity in mice. Methods: We used the behavioral light/dark choice test to evaluate whether high anxiety has an impact on various parameters of cellular (granulocytes, monocytes, total lymphocytes, TCD4+, TCD8+ and NK numbers) and humoral (IgA, E and G concentrations) immunity. Secondly, we investigated whether the cellular and humoral immune systems of mice with contrasting levels of anxiety responded differently to stressors (such as physical restraint) by monitoring blood markers of the both types of immunity. Results: High levels of anxiety inhibited part of the cellular and humoral immune systems by significantly decreasing total lymphocytes numbers (including TCD4+ and TCD8 +) and immunoglobulin (A and E) concentrations. However, no significant changes in the number of granulocytes, monocytes or NK cells were observed. As a consequence, overall, our results suggest that high anxiety led to a decrease in the efficiency of the immune system of anxious mice. On the other hand, our findings also showed that restraint stress (acute and subacute) produced the same immunological profile as high anxiety in mice. This was independent of the animals' anxiety status. At the same time, we observed that restraint stress produced significant increases in the levels of granulocytes and monocytes. Conclusions: High anxiety and restraint stress exerted adverse effects on cellular and humoral immunity in mice. While the effect of restraint stress was independent of the anxiety levels in mice, this stress led to an aggravation of the immune response from the high degree of anxiety. Therefore, anxious subjects could be more vulnerable to infections and inflammation, particularly when they are exposed to stressful situations.
European Journal of Pharmacology, 627 (1-3), pp. 173-176.
Rammal, H., Bouayed, J., Soulimani, R.
Disturbances in oxidative metabolism are involved in many acute and chronic diseases, as well as in several other conditions. The objective of the present study was to examine the relationship between the level of intracellular reactive oxygen species in the peripheral blood granulocytes of mice, as evaluated by 2',7'-dichlorofluorescin diacetate (DCFH-DA), a sensor of reactive oxygen species, and the aggressive behavior of these mice, as estimated by the resident/intruder test. Our results showed a significant, linear and positive relationship (P < 0.001) between the intracellular redox status of peripheral blood granulocytes and the aggressive behavior levels of adult male mice (correlation coefficients (R2) ranging from 0.75 to 0.77). This suggests that the granulocytes of aggressively behaving mice have high levels of oxidative stress.
Journal of Dairy Science, 93 (7), pp. 2906-2921.
Rousseau-Ralliard, D., Goirand, F., Tardivel, S., Lucas, A., Algaron, F., Mollé, D., Robert, V., Auchère, D., Boudier, J.-F., Gaillard, J.-L., Monnet, V., Tauzin, J., Grynberg, A.
A great number of milk-derived peptides have been shown to exhibit angiotensin converting enzyme (ACE) inhibitory properties and thus potential utility in the regulation of blood pressure. The present work aimed to investigate the effects of 2 milk trypsin hydrolysates from αs1- and αs2-casein (CH1 and CH2, respectively) on ACE activity evaluated in human umbilical vein endothelial cells (HUVEC) in vitro, rat aortic tissues ex vivo, and renovascular hypertensive rat in vivo. Incubation of HUVEC and rat aortic tissues with CH1 or CH2 induced a concentration-dependent inhibition of hydrolysis of the ACE substrate hippuryl-histidyl-leucine (HHL), the hydrolysates being much less potent than perindopril (an ACE inhibitor). However, in contrast to perindopril, CH1 and CH2 failed to modify angiotensin I-induced aortic ring vasoconstriction. The HPLC profiles of rat plasma after intragastric administration were variable among individuals but none of the observed peaks corresponded to peptides comprising CH1 or CH2 or to fragments of these peptides. During 4 wk of cardiovascular monitoring, in hydrolysate-fed renovascular hypertensive rats, systolic blood pressure weakly decreased compared with the control group. However, the CH1-fed hypertensive rats exhibited a decrease of heart rate during the nocturnal period of activity. To conclude, our results show that CH1 and CH2 inhibited ACE activity in HUVEC and rat aortic tissue but failed to antagonize the aortic-constricting effects of the natural agonist angiotensin I. Moreover, we demonstrated that CH1, to a greater extent than CH2, can slightly affect cardiovascular parameters although the ingested bioactive peptides could not be detected in the blood.
Animal, 4 (2), pp. 1-10.
Schlegel, P., Nys, Y., Jondreville, C.
The study was conducted to evaluate the effects of dietary zinc addition (0 or 15 mg/kg of Zn as inorganic or organic zinc) to three maize-soybean meal basal diets varying in their native Zn, phytic P contents and phytase activity (expressed in kg of feed: P- with 25 mg Zn and 1.3 g phytic P, P+ with 38 mg Zn and 2.3 g phytic P or P+/ENZ being P+ including 500 units (FTU) of microbial phytase per kg) in two monogastric species (piglets, broilers). Measured parameters were growth performance, zinc status (plasma, and bone zinc) and soluble zinc in digesta (stomach, gizzard and intestine). The nine experimental diets were fed for 20 days either to weaned piglets (six replicates per treatment) or to 1-day-old broilers (10 replicates per treatment). Animal performance was not affected by dietary treatments (P > 0.05) except that all P- diets improved body weight gain and feed conversion ratio in piglets (P < 0.05). Piglets fed P- diets had a better Zn status than those fed P+ diets (P < 0.05). In both species, Zn status was improved with supplemental Zn (P < 0.05), irrespective of Zn source. Phytase supplementation improved piglet Zn status to a higher extent than adding dietary Zn, whereas in broilers, phytase was less efficient than supplemental Zn. Digestive Zn concentrations reflected the quantity of ingested Zn. Soluble Zn (mg/kg dry matter) and Zn solubility (% of total Zn content) were highest in gizzard contents, which also presented lower pH values than stomach or intestines. The intestinal Zn solubility was higher in piglet fed organic Zn than those fed inorganic Zn (P < 0.01). Phytase increased soluble Zn in piglet stomach (P < 0.001) and intestine (P = 0.1), but not in broiler gizzard and intestinal contents. These results demonstrate (i) that dietary zinc was used more efficiently by broilers than by piglets, most probably due to the lower gizzard pH and its related higher zinc solubility; (ii) that zinc supplementation, irrespective of zinc source, was successful in improving animal's zinc status; and (iii) suggest that supplemented Zn availability was independent from the diet formulation. Finally, the present data confirm that phytase was efficient in increasing digestive soluble Zn and improving zinc status in piglets. However, the magnitude of these effects was lower in broilers probably due to the naturally higher Zn availability in poultry than in swine.
J. Fish Biol. 77: 257-278.
Teletchea F. Fontaine P.
Review. Aquaculture 2: 209-222.
Wang, N., Teletchea, F., Kestemont, P., Milla, S., Fontaine P.
Albeitar, 135, pp. 50-52.
Jondreville, C., Genthon, C., Bouguennec, A., Nys, Y.
Comptes Rendus - Biologies, 333 (9), pp. 663-669.
Muanda, F.N., Dicko, A., Soulimani, R.
The present study was carried out to evaluate the antioxidant activities of the root bark extract of Securidaca longepedunculata. This plant material is commonly used in folk medicine in several parts in the world. The bark extracts of S. longepedunculata were evaluated for their total phenols, flavonoids, anthocyanins, tannins content and total antioxidant capacity. The compounds were identified and quantified both by RP-HPLC and UV spectrophotometer; the antioxidant capacity was assessed by ABTS and DPPH tests and expressed as IC50. The total phenolic compounds determinate was 9.86 mg gallic acid equivalents/g dw, the total flavonoid contents was 5.85 mg catechin equivalents/g dw, the total anthocyanin contents was 0.032 mg cyanidin-3-glycosyl equivalents/g dw and the condensed tannins content were 1.03 mg catechin equivalents/g dw. The major compound identified using RP-HPLC was quercetin (0.98 mg/ml). The IC50 value reached 5.5 µg/ml, revealing that the root barks of S. longepedunculata have a very high antioxidant and anti-inflammation properties.
Bulletin de Veille Scientifique de l'AFSSET, 10, pp. 96-101.
Schroeder, H.
Bulletin de Veille Scientifique de l'ANSES, 11, pp. 83-88.
Schroeder, H.
Can we use stable isotopes for ecotoxicological studies? Effect of DDT on isotopic fractionation in Perca fluviatilis
Chemosphere, 76 (6), pp 734-739.
Banas, D., Vollaire, Y., Danger, M., Thomas, M., Oliveira-Ribeiro, C.A., Roche, D., Ledoré, Y.
Stable isotope analysis is frequently used as a complementary method of dietary analysis, to describe trophic relationships and assess food-web structure. These studies allow a precise determination, based on the calculation of a diet-tissue fractionation factor. The fractionation factor, determined for whole organisms or specific tissues, may vary substantially in natura. In the present study, δ13C and δ15N were assessed in lipid-free tissues (spleen, liver, viscera, scales, gills, spine, white muscle, brain) and in available energy reserves (proteins, glycogen, lipids) of Eurasian perch (Perca fluviatilis) reared under controlled conditions and fed for 4 months with the same artificial diet. Some discrepancies in δ15N and δ13C data were observed among tissues, respectively up to 3.43‰ and 2.54‰ for δ15N and δ13C. The 15N signature in organs depends on their metabolic activity. Despite a significant δ13C enrichment from feed to tissues, the lipids in spine, liver and viscera exhibit a certain stability.
Short hypoxia could attenuate the adverse effects of hyperhomocysteinemia on the developing rat brain by inducing neurogenesis.
Experimental Neurology, 216 (1), pp. 231-238.
Blaise, S.A., Nedelec, E., Alberto, J.M., Schroeder, H., Audonnet, S., Bossenmeyer-Pourie, C., Gueant, J.L., Daval, J.L.
Gestational deficiency in methyl donors such as folate and vitamin B12 impairs homocysteine metabolism and can alter brain development in the progeny. Since short hypoxia has been shown to be neuroprotective in preconditioning studies, we aimed to investigate the effects of brief, non-lesioning neonatal hypoxia (100% N2 for 5 min) on the developing brain of rats born to dams fed either a standard diet or a diet lacking vitamins B12, B2, folate and choline until offspring\'s weaning. While having no influence on brain accumulation of homocysteine and concomitant apoptosis in 21-day-old deficient pups, exposure to hypoxia reduced morphological injury of the hippocampal CA1 layer. It also markedly stimulated the incorporation of bromodeoxyuridine (BrdU) in permissive areas such as the subventricular zone and the hippocampus followed by the migration of new neurons. Scores in a locomotor coordination test (days 19-21) and learning and memory behavior in the eight-arm maze (days 80-84) were found to be significantly improved in rats exposed to hypoxia in addition to the deficient diet. Therefore, by stimulating neurogenesis in rat pups, brief neonatal hypoxia appeared to attenuate the long-term effects of early exposure to a deficiency in nutritional determinants of hyperhomocysteinemia.
Toxicology, 259 (3), pp. 97-106.
Bouayed, J., Desor, F., Rammal, H., Kiemer, A.K., Tybl, E., Schroeder, H., Rychen, G., Soulimani, R.
The harmful effects of exposure to benzo[a]pyrene (B[a]P), which is a neurotoxic pollutant, on mammalian neurodevelopment and/or behaviour as yet remain widely unclear. In the present investigation, we evaluated the impact of the lactational exposure to B[a]P on postnatal development of pups and behaviour of young mice. The neurobiological effects of B[a]P during lactation were also evaluated on pups\' brain. Here, we found that lactational exposure to B[a]P at 2 and 20 mg/kg affects the neuromaturation of pups by significantly decreasing their reflex as highlighted in surface righting reflex and negative geotaxis tests. However, we noted a significant increase in muscular strength of lactationally B[a]P mg/kg-exposed pups, which was probably due to the impact of the exposure to this toxic compound on body weight gain. At the pup stage, lactational exposure to B[a]P also provoked a neurobiological change, which was assessed by determination of neuronal receptor gene expression. Indeed, a significant reduction in gene expression of 5HT1A receptors in pups exposed to B[a]P through lactation was found in comparison to controls. Additionally, attenuation in the expression of MOR1 mRNA was observed, but statistically significant only in animals receiving the higher dose. Neither the expression levels of ADRA1D nor GABAA mRNA were altered. Interestingly, the harmful effects of lactational exposure to B[a]P on behaviour and cognitive function were still found despite a long post-weaning period. Young mice whose mothers were exposed to B[a]P displayed a disinhibition behaviour towards the aversive spaces of the elevated plus maze. Furthermore, a significant increase of spontaneous alternation in the Y-maze was observed, but only in young mice whose mothers were orally exposed to the lower dose of B[a]P. Our results suggest a close link between the neurobiological change highlighted in pups\' brain and the different behavioural disturbances observed during postnatal development period until young adult stage.
Journal of Hazardous Materials, 169 (1-3), pp. 581-585.
Bouayed, J., Desor, F., Soulimani, R.
Benzo[α]pyrene (B[α]P) is a neurotoxic pollutant which is also able to affect some behaviour and cognitive function. Here we report that a subacute oral exposure to B[α]P increases aggressiveness and affects copulatory behaviour in male mice. Indeed, after 3 weeks of exposure to B[α]P at 0.02 and 0.2 mg/kg, we have observed that B[α]P 0.02 mg/kg-treated male mice are more aggressive than control mice in resident-intruder test because a significant decrease in the latency time of the first attack and a significant increase in the number of attacks in B[α]P 0.02 mg/kg-treated mice were found. On the other hand, we have found that subacute exposure (4 weeks) to B[α]P, does not affect the appetitive aspects and sexual motivation in copulatory behaviour because the latency to the first mount between control and B[α]P-treated male mice was not significantly different. We have nevertheless, surprisingly found that B[α]P (0.02-0.2) mg/kg-treated mice have performed significantly more sexual behavioural acts including mounting, intromission latency and intromission frequency than control mice. Although these last results suggest that B[α]P improves the consummatory aspects of sexual behaviour, we cannot conclude that this neurotoxic pollutant has advantage of sexual function because B[α]P has been shown to alter the monoaminergic neurotransmitter system and causes endocrine dysregulation via toxic effect.
Journal of Medicinal Food, 12 (4), pp. 861-868.
Bouayed, J., Rammal, H., Dicko, A., Younos, C., Soulimani, R.
Epidemiological and scientific research has contributed to the identification of the key role of dietary antioxidants in maintaining human health by preventing oxidative damage to cellular components. The antiradical activity of seven varieties of plums and their protective effects against oxidative stress were comparatively evaluated in mouse granulocytes in this study using a 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) test and a cellular test. The class of phytochemical compounds responsible for the main antioxidant capacities observed was also investigated. The ABTS and cellular tests revealed that the total antioxidant capacities, expressed as vitamin C equivalents, ranged from 691.2 to 2,164.64 mg and from 613.98 to 2,137.59 mg per 100 g of fresh weight, respectively, suggesting that plums are rich in natural antioxidants and appreciably protect granulocytes from oxidative stress. Our results showed a linear correlation between either total phenolic or flavonoid contents and total antioxidant capacity, revealing that these compounds contribute significantly to the antioxidant activity of plums. The major polyphenolics in plums, identified and quantified using reversed-phase high-performance liquid chromatography, were tested to evaluate their protective effect on peripheral blood granulocytes from oxidative stress. The results suggest that individual polyphenolics contribute directly to the total protective effect of plums.
Oxidative Medicine and Cellular Longevity, 2 (2), pp. 63-67.
Bouayed, J., Rammal, H., Soulimani, R.
High O2 consumption, modest antioxidant defenses and a lipid-rich constitution make the brain highly vulnerable to redox imbalances. Oxidative damage in the brain causes nervous system impairment. Recently, oxidative stress has also been implicated in depression, anxiety disorders and high anxiety levels. The findings which establish a link between oxidative stress and pathological anxiety have inspired a number of other recent studies focusing on the link between oxidative status and normal anxiety and also on a possible causal relationship between cellular oxidative stress and emotional stress. This review examines the recent discoveries made on the link between oxidative status and normal anxiety levels and the putative role of oxidative stress in genesis of anxiety. We discuss the different opinions and questions that exist in the field and review the methodological approaches that are being used to determine a causal relationship between oxidative and emotional stress.
Tissue distribution of antimony (Sb) in piglets orally given graded levels of Sb (V)
Toxicological & Environmental Chemistry, 91 (2), pp. 267-278.
Caboche, J., Jondreville, C., Tack, K., Denys, S., Rychen, G., Feidt, C.
The potential risks from oral intake of soil antimony (Sb) depends mainly on the amount of metal ingested and its bioavailability. Relative bioavailability may be determined by comparing Sb present in soil to a reference compound, taking into account accumulation in different target tissues or excretion. However, due to the lack of scientific knowledge concerning the fate of Sb in the organism, there is a need to study the absorption and distribution of Sb in order to select target tissues for assessment of bioavailability of Sb in soils. Thus, 45 piglets were exposed to a soluble pentavalent antimony salt (KSb(OH)6), for 15 days at concentrations ranging from 0-1600 µg Sb/kg body weight (BW) per day. Following the exposure period, blood, plasma, liver, spleen, kidneys, hair, bone, bile and urine were obtained to measure Sb concentrations by ICP-MS. Results showed that tissue Sb levels were dose-related. Higher Sb concentrations were found in urine, kidneys, hair, bone and liver. Sb(V) was not detectable in blood and plasma. In the case of highly contaminated soil with soluble forms of Sb in concentrations ranging from 200-1600 µg Sb/kg BW, kidneys, liver and spleen are the most reliable compartments to determine Sb bioavailability from soil. However, for the soils with lower levels of contamination and a low Sb bioaccessibility, urine may serve as a relevant compartment.
Growth heterogeneity in rearing sea bass (Dicentrarchus labrax) : test of hypothesis with an iterative energetic model
Animal 3:9, pp 1299–1307
Campeas, A., Brun-Bellut, J., Baras, E., Kestemont, P., Gardeur, J.N.
This study aimed at modeling the relative importance of food intake on growth heterogeneity among cultured sea bass (Dicentrarchus labrax). First, we designed an individual growth model comprising 5 compartments (Energy intake, Losses, Net Energy, Recovered Energy and Maintenance). This model was calibrated with a first experiment carried out in 8 tanks, 130 juveniles (11 g) per tank were fed by a self-feeder (84 days, 20°C, 16L:8D, 30 g NaCl.L-1). A second experiment was performed to better understand the relation between individual food intake, individual growth and growth heterogeneity, using the model as a tool for a hypothetico-deductive approach on growth heterogeneity (135 PIT-tagged fish, same rearing conditions as above, individual food intake measured by x-ray every 14 days). The tested hypotheses were that food intake was a) homogeneous, b) proportional to the fish weight (i.e. to W1.00) x-ray c) proportional to W0.66, and d) reflected by the X-ray measurements of food intake. For each hypotheses, a simple linear regression between experimental and simulated results was produced, The Fitness indicators of these analyses, together with their confidence intervals (calculated by bootstrapping), allowed testing the relevance of these hypotheses. The analysis indicated that growth heterogeneity was largely accounted for by individual variations of food intake, as revealed by the x-ray analysis, and that food intake was proportional to W1.00, which suggests a dominance hierarchy where small fish are incapable of feeding maximally.
Bioavailability of polycyclic aromatic hydrocarbons (PAHs) from soil and hay matrices in lactating goats.
Journal of Agricultural and Food Chemistry, 57 (12), pp. 5352-5357.
Costera, A., Feidt, C., Dziurla, M.-A., Monteau, F., Le Bizec, B., Rychen, G.
This experiment was aimed at determining the bioavailability of three polycyclic aromatic hydrocarbons (PAHs) in goats: phenanthrene, pyrene, and benzo[a]pyrene. A Latin square design procedure was carried out involving three alpine lactating goats and three PAH-contaminated matrices (soil, hay, and oil as a control). Milk and urine samples were collected to assess PAH and hydroxy-PAH excretion kinetics and to compare the carry-over rates for the different matrices. PAHs were found to be excreted mainly in urine; metabolite concentrations were about 20 times higher in urine than in milk. 1-Hydroxypyrene was the major metabolite in both body fluids (8000 ng/mL urine and 450 ng/mL milk); it may be considered as a valuable indicator of the ruminant exposure to PAHs. Apparent absorption of PAHs estimated by the metabolite excretion in urine and milk reached 34% for pyrene from soil, and the bioavailability of soil-bound PAHs was found to be similar to the bioavailability of PAHs from the other matrices.
Journal of Biological Chemistry, 284 (14), pp. 9299-9310.
Couturier, J., Koh, C.S., Zaffagnini, M., Winger, A.M., Gualberto, J.M., Corbier, C., Decottignies, P., Jacquot, J.P., Lemaire, S.D., Didierjean, C., Rouhier, N.
Effects of a Bovine Alpha S1-Casein Tryptic Hydrolysate (CTH) on Sleep Disorder in Japanese General Population
The Open Sleep Journal, 2009, 2, 31-37.
de Saint-Hilaire, Z., Messaoudi, M., Desor, D., Kobayashi, T.
Biodisponibilité et bioaccessibilité des métaux et metalloïdes des sols pollués pour la voie orale chez l’homme.
Environnement, Risques & Santé, 8 (5), pp. 433-438.
Denys, S., Caboche, J., Feidt, C., Hazebrouck, B., Dor, F., Dabin, C., Floch-Barneaud, A., Tack, K.
Dans la gestion des sols contaminés, la notion de biodisponibilité des polluants des sols est fréquemment évoquée comme permettant d’optimiser l’évaluation du risque sanitaire. Toutefois, une certaine confusion existe entre les notions de biodisponibilité et bioaccessibilité des polluants dans les sols. Cela engendre des difficultés pour, d’une part, intégrer au mieux ces notions dans la gestion des sites et, d’autre part, sélectionner un protocole de mesure. L’objectif de cette synthèse est tout d’abord de définir les notions de biodisponibilité et bioaccessibilité pour l’homme des polluants des sols et d’établir les liens existant entre ces deux paramètres. Dans un second temps, différents protocoles permettant de caractériser ces deux paramètres sont décrits. Enfin, un retour d’expérience international faisant état de l’utilisation de ces deux paramètres dans la gestion effective des sites pollués est exposé.
Impact de la nutrition sur l’excrétion d’azote, de phosphore de cuivre et de zinc des porcs et sur les émissions d’ammoniac, de gaz à effet de serre et d’odeurs.
Productions Animales, 22 (1), pp. 41-48.
Dourmad, J.Y., Rigolot, C., Jondreville, C.
Can the mammopathogenic Escherichia coli P4 strain have a direct role on the caseinolysis of milk observed during bovine mastitis?
Journal of Dairy Science, 92 (4), pp. 1398-1403.
Dufour, D., Jameh, N., Dary, A., Le Roux, Y.
During bacterial bovine mastitis, the quality of milk is altered because of caseinolysis. Endogenous potential actors in milk responsible for this caseinolysis have been well studied, unlike the exogenous bacterial ones. The aim of this study was to evaluate the direct role in caseinolysis of a mammopathogenic strain, Escherichia coli P4. Secretion of at least 4 extracellular bacterial caseinolytic enzymes was highlighted by zymography, in 3 different growth media, and at each bacterial growth state, suggesting that their expression was constitutive. Different experimental conditions to evaluate caseinolytic potential did not show any significant caseinolytic activity of E. coli P4 and of the 4 extracellular proteases detected, suggesting that the high caseinolysis observed during E. coli bovine mastitis does result from endogenous milk actors.
Développement de la pisciculture continentale européenne et domestication de nouvelles espèces.
Cahiers Agricultures, 18 2-3, pp. 144-147.
Fontaine P.
Domestication de nouvelles espèces et développement durable de la pisciculture.
Cahiers Agricultures, 18 2-3, pp. 119-124.
Fontaine P., Legendre M., Vandeputte M., Fostier A.
Variability and molecular typing of Streptococcus thermophilus strains displaying different proteolytic and acidifying properties
International Dairy Journal, 19 (2), pp. 89-95.
Galia, W., Perrin, C., Genay, M., Dary, A.
Proteolytic and acidifying properties of Streptococcus thermophilus strains isolated from yoghurt or cheeses were evaluated. Among 30 strains tested, 12 exhibited cell envelope-associated proteinase activity (PrtS+), three displayed a slight PrtS activity (PrtS+/−) and 15 were PrtS−, despite the presence of the corresponding gene (prtS) in eight of them. Sequencing of the prtS gene in four PrtS− and one PrtS+ strains revealed that the absence of PrtS activity in the PrtS− strain probably results from an alteration of the prtS regulation. The strains displaying the highest acidifying capacities were all PrtS+. All but one PrtS+ strains were phylogenetically close, as shown by the sequencing of their rDNA internal transcribed spacer (ITS) 16S-23S. More specifically, the high proteolytic and acidifying capacities are associated with the presence of a type II-ITS.
prtH2, not prtH, is the ubiquitous cell wall proteinase gene in Lactobacillus helveticus
Applied and Environmental Microbiology, 75 (10), pp. 3238-3249.
Genay, M., Sadat, L., Gagnaire, V., Lortal, S.
Productions Animales, 22 (3), pp. 161-178.
Guemene, D., Germain, K., Aubert, C., Bouvarel, I., Cabaret, J., Chapuis, H., Corson, M., Jondreville, C., Juin, H., Lessire, M., Lubac, S., Magdelaine, P., Leroyer, J.
Phytotherapie, 7 (4), pp. 197-201.
Kambouche, N., Merah, B., Derdour, A., Bellahouel, S., Benziane, M.M., Younos, C., Firkioui, M., Bedouhene, S., Soulimani, R.
Anabasis articulata is a plant used by Algerian traditional medicine as a remedy for the treatment of diabetes. The aqueous extract was found to be non-toxic until at 1,000 mg/kg during period (24 and 72 hours). Experiments were performed in non-diabetic mice, and in diabetic mice (alloxan treated mice). Our results showed that the orally administration at a dose of 400 mg/kg decreased the glycaemia to 29.89% (p < 0.05), 6 hours after administration, corresponding to the greatest decrease of blood glucose in normoglycaemic mice (hypoglycemic effect). They also show that orally administration at 400 mg/kg decreased the glycaemia to 74.48% (p < 0.05) 21 days after treatment. Phytochemical screening exhibited that the aqueous extract contains alkaloid and saponin components with percentage 1.25 and 1.30%, respectively. Our findings displayed that saponin (at 5 mg/kg) was the active fraction, as it permitted to restore the normal blood glucose levels, after 21 days of treatment, and that the alkaloid fraction did not significantly reduce the blood glucose level. The present study shows the no toxic effect in sub-acute administration and to confirm the anti-diabetic traditional use of Anabasis articulata. With active support in saponins triterpenoids compounds.
African Journal of Biotechnology, 8 (20), pp. 5578-5583.
Kambouche, N., Merah, B., Derdour, A., Bellahouel, S., Bouayed, J., Dicko, A., Younos, C., Soulimani, R.
Anabasis articulata leaves decoction is widely used by Algerian traditional medicine practitioners as a remedy for the treatment of diabetes. The aqueous extract was found to be non-toxic at 1000 mg/kg, as no deaths or hazardous signs were recorded during treatment or the observation period (24 and 72 h) in either control or treated groups of mice. Experiments were performed in non-diabetic mice, and in hyperglycemic mice (glucose treated and alloxan treated mice) to confirm the antidiabetic potential of A. articulata. Our results showed that the orally administration at a dose of 400 mg/kg decreased the glycaemia by 29.89% after 6 h (p < 0.05), corresponding to the greatest decrease of blood glucose in normoglycaemic mice. This dose also lowered blood glucose concentrations in diabetic mice revealing antihyperglycemic effect of A. articulata leaves. The class of phytochemical responsible for antidiabetic effects in aqueous leaf extract was also investigated. Phytochemical screening showed that the aqueous extract contains alkaloids (1.25%) and saponin (1.30%). Our findings showed that saponin (5 mg/Kg) was the active fraction, since it restores the normal blood glucose levels after 21 days of treatment. The alkaloid fraction did not significantly reduce the blood glucose level. The present study confirms the antidiabetic proprieties of A. articulata leaves previously reported by Algerian healers.
Experimental and Toxicologic Pathology, 61 (2), pp. 161-167.
Kebieche, M., Lakroun, Z., Lahouel, M., Bouayed, J., Meraihi, Z., Soulimani, R.
Anticancer therapy with epirubicin (EPI) results in acute hepatotoxicity, likely due to the generation of free radicals. However, the oxidative status of rat liver cells and mitochondria after EPI toxicity has not been investigated. In the present study, we first investigated the pro-oxidant effect of EPI on both hepatic cells and mitochondrial function. Injection of EPI into rats at a dose of 9 mg/kg (cumulative dose in human chemotherapy), induced hepatic dysfunction, as revealed by a significant increase in serum glutamate oxaloacetate transaminases (SGOT) and glutamate pyruvate transaminases (SGPT). Oxidative stress in liver cells and mitochondria was provoked by EPI because a statistically significant reduction of catalase (CAT), superoxide dismutase (SOD) and cytosolic glutathione (GSH) levels, and a significant increase in malonedialdehyde (MDA) levels - an indicator of lipid peroxidation that can perforate biological membranes - were observed. Second, the protective effect of quercetin (QE) (0.33 mg/kg) against EPI-induced oxidative stress was also investigated. Indeed, the pretreatment of rats with QE protected liver cells and mitochondria from oxidative stress. This treatment prevented hepatic dysfunction by maintaining normal levels of serum transaminases following the inhibition of their hepatic leakage by preventing lipid peroxidation. Thus, QE works through the prevention of cellular membrane perforation and the antioxidant defense system of mitochondria from liver cells, which represent compartments for the permanent production of reactive oxygen species (ROS) through the respiratory chain.
Two-dimensional cartography of equine beta-casein variants achieved by isolation of phosphorylation isoforms and control of the deamidation phenomenon
Journal of Dairy Science, 92 (6) pp. 2389-2399.
Matéos, A., Girardet, J.-M., Mollé, D., Dary, A., Miclo, L., Gaillard, J.-L.
Because of variable degrees of phosphorylation, alternative splicing, and probable instability resulting from nonenzymatic deamidation, equine β-casein presents a complex pattern by 2-dimensional electrophoresis that needs clarification. β-Casein prepared from Haflinger mare’s milk by hydrophobic interaction chromatography was fractionated by ion-exchange chromatography according to the degree of phosphorylation. Isoforms were identified by mass spectrometry; they corresponded to the full-length protein having 3 to 7 phosphate groups and to the splicing variant involving exon 5 and containing 4 to 7 phosphate groups. Investigations of nonenzymatic deamidation showed that β-casein did not deamidate spontaneously in stored milk and during the different steps of chromatography, but deamidation could occur when 2-dimensional electrophoresis was performed, increasing the β-casein pattern complexity. This phenomenon was strongly minimized when the first dimension step was carried out at 10°C instead of at room temperature. Finally, spot attribution on 2-dimensional pattern of β-casein was achieved by mixing each phosphorylation isoform in its native state with the whole β-casein fraction.
Equine alpha-s1-casein: characterization of alternative splicing isoforms and determination of phosphorylation levels of multiple isoforms
Journal of Dairy Science, 92 (8), pp. 3604-3615.
Matéos, A., Miclo, L., Mollé, D., Dary, A., Girardet, J.-M., Gaillard, J.-L.
Alpha-s1-casein was isolated from Haflinger mare’s milk by hydrophobic interaction chromatography and displayed great micro-heterogeneity by 2-dimensional electrophoresis, probably because of a variable degree of phosphorylation and alternative splicing events. The aim of the present work was to investigate the complexity of the mare’s alpha-s1-casein. The different isoforms present in milk were submitted to a double treatment of dephosphorylation, first by using alkaline phosphatase and then acid phosphatase to achieve complete dephosphorylation. The apoforms were then analyzed by electrospray ionization mass spectrometry. The results revealed the existence of a full-length protein and 7 variants resulting from posttranscriptional modifications; that is, exon skipping involving exon 7, exon 14, or both and use of a cryptic splice site encoding a glutamine residue. The determination of the different phosphorylation degrees of the native isoforms of alpha-s1-casein was finally achieved by electrospray ionization mass spectrometry analysis after fractionation of the isoforms by ion-exchange chromatography. Thus, 36 different variants of equine alpha-s1-casein were identified with several phosphate groups ranging from 2 to 6 or 8 depending on whether exon 7 was skipped.
Anxiolytic-like effects and safety profile of a tryptic hydrolysate from bovine alpha s1-casein in rats.
Fundamental & Clinical Pharmacology 23 (3), pp. 323-330.
Messaoudi, M., Lalonde, R., Schroeder, H., Desor, D.
The anxiolytic activity and adverse benzodiazepine-like effects of a bovine alpha s1-casein tryptic hydrolysate (CH) were evaluated. The effects of CH orally administered at doses of 5 and 15 mg/kg were compared with those of diazepam (DZ) at 3 mg/kg in the conditioned defensive burying test. Rats treated either with CH at 15 mg/kg or with DZ showed a decrease in anxiety. A drug-related difference was observed in terms of duration, as the anxiolytic-like action of CH was maintained after 7 days with twice-daily administration, whereas that of DZ was not. CH and DZ were then evaluated for their potential effects on memory in a passive avoidance paradigm. CH-treated rats had significantly longer latencies before entering the dark compartment where they were previously delivered a shock, indicating better retention relative to DZ-treated rats. In the final test, CH and DZ were evaluated for place preference, an index of the possible addictive potential of these substances. DZ-treated rats spent more time in the compartment associated with drug exposure than control rats. This effect was not found in CH-treated rats. Thus, CH did not display side effects associated with DZ, despite its affinity for gamma-aminobutyric acid(A) (GABAA) receptors. Specific linking of CH on GABAA receptor function involved in anxiolysis, but not on that implied in memory-impairing effects, may be hypothesized to explain its specific activity. This profile might render it advantageous for nutritional purposes.
Gen. Comp. Endocrinol. 163, 242-250.
Milla S., Mandiki R., Hubermont P., Rougeot C., Melard C., Kestemont P.
Physiol. A. 153, 242-251.
Milla S., Wang N., Mandiki R., Kestemont P.
Plos One, 4 (12), e8268
Orozco-Barrios, C.E., Battaglia-Hsu, S.F., Arango-Rodriguez, M.L., Ayala-Davila, J., Chery, C., Alberto, J.M., Schroeder, H., Daval, J.L., Martinez-Fong, D., Gueant, J.L.
Relative bioavailability of soil-bound polycyclic aromatic hydrocarbons in goats.
Chemosphere, 77 (1), pp. 115-122.
Ounnas, F., Jurjanz, S., Dziurla, M.A., Guiavarc'h, Y., Feidt, C., Rychen, G.
This study aimed at determining the relative bioavailability (RB) of three soil-bound PAH model compounds (phenanthrene [PHE], pyrene [PYR] and benzo[a]pyrene [BaP]) in four lactating goats. RB was estimated by comparing the urinary or milk excretion of the major mono-hydroxylated metabolites of PAHs after ingestion of PAH spiked-soil and -oil feeds. A series of three increasing doses were orally administered in order to estimate the dose response of the two different matrices. The results of this study reveal that urinary excretion prevailed compared to milk excretion (30-fold higher). The recovery rate of mono-hydroxylated metabolites of PAHs in urine and milk indicate that PYR was absorbed at a minimum level of 36%. 3-OH PHE excreted in urine suggests a minimal absorption of at least 5% for PHE. 3-OH BaP remained under the limits of detection and quantification and no RB could be calculated for this compound. RB of soil-bound PYR compared to PYR in oil was 61% and 50% in milk and urine, respectively. Thus, a significantly reduced RB of PYR in soil has been shown. On the other hand, no significant differences were observed between oil and soil for urinary 3-OH PHE (RB = 100%). These results show that the soil matrix significantly reduces the bioavailability of certain PAHs. The decrease of bioavailability seems to be dependent on the compounds, i.e. higher for PYR than for PHE. This study also suggests that soil ingestion should be taken into account in risk assessment studies.
Phytotherapie, 7 (4), pp. 191-196.
Rammal, H., Bouayed, J., Desor, F., Younos, C., Soulimani, R.
Momordica charantia (L.) [Cucurbitaceae], more commonly known as the bitter cucumber or bitter melon, is a plant used for food and medicine. In the Ayurvedic tradition it is used to treat a range of disorders, including diabetes. This study has demonstrated the plant's anti-hyperglycaemic effect in mice with alloxan monohydrate induced diabetes. Two extracts were prepared, from both the fresh and the dried fruit of the plant, and their effects on blood sugar levels were compared with the reference anti-diabetes molecule glibenclamide. Aqueous extract of the fresh fruit at a dose of 200 mg/kg demonstrated a significant reduction in glycemia (62%), comparable with that of glibenclamide at a dose of 10 mg/kg. The two extracts at different doses showed no signs of toxicity. Thus, aqueous extract of the edible plant M. charantia would appear to be a viable alternative for reducing glycemia as well as providing an auxiliary and complementary treatment which would limit the secondary effects of allopathic remedies using synthetic drugs.
Phytotherapie, 7 (3), pp. 161-164.
Rammal, H., Bouayed, J., Desor, F., Younos, C., Soulimani, R.
Phytotherapie, 7 (1), pp. 26-27.
Rammal, H., Bouayed, J., Desor, F., Younos, C., Soulimani, R.
Phytotherapie, 7 (3), pp. 157-160.
Rammal, H., Bouayed, J., Younos, C., Soulimani, R.
Phytotherapie, 7 (1), pp. 28-30.
Rammal, H., Younos, C., Bouayed, J., Chakou, A., Necerbey, N., Soulimani, R.
Rice fields regulate organochlorine pesticides and PCBs in lagoons of the Nature Reserve of Camargue.
Chemosphere, 75 (4), pp. 526-533.
Roche, H., Vollaire, Y., Martin, E., Rouer, C., Coulet, E., Grillas, P., Banas, D.
In order to assess pollutant transfer in Camargue ponds from bordering agrosystems, a biomonitoring assay was conducted in irrigation and drainage channels of rice fields in the Rhone Delta (France). A filter-feeding bivalve, the Asian clam, Corbicula fluminea, was used as bioindicator and caged in upstream and downstream channels of an area of conventional rice fields. After 6 weeks incubation, many lipophilic biocides were identified in Corbicula tissues, including pesticides used in rice plantations (pretilachlor, oxadiazon), pesticides presumed in use in the Rhone basin [diuron and its metabolite 3,4 dichloroaniline (3,4-DCA)] and organochlorine pesticides (OCPs) banned for several decades. In addition, PCBs were highly bioaccumulated in Corbicula. Downstream bivalves had significantly lower concentrations of OCPs, PCB and 3,4-DCA. However, the exposure biomarkers (glutathione S-transferase, catalase and propionylcholinesterase) were not correlated with the decreased concentrations. The results of this experiment raise several questions concerning the potential role of immersed plants in a retention process.
Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France).
Environmental Pollution, 157 (8-9), pp. 2493-2506.
Roche, H., Vollaire, Y., Persic, A., Buet, A., Oliveira-Ribeiro, C., Coulet, E., Banas, D., Ramade, F.
During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas.
Control of puberty in farmed fish.
General Comparative Endocrinology, 165, 483-515
Taranger G.L., Carillo M., Schultz R.W., Fontaine P., Zanuy S., Felip A., Weltzien F.A., Dufour S., Karlsen O., Norberg B., Andersson E., Hansen T.
Comparative analysis of reproductive traits in 65 freshwater fish species: application to the domestication of new fish species.
Reviews in Fish Biology and Fisheries 19, pp 403–430
Teletchea, F., Fostier, A., Kamler, E., Gardeur, J.N., Le Bail, P.Y., Jalabert B., Fontaine P.
The relationship of oocyte diameter and incubation temperature to incubation time in temperate freshwater fish species
Journal of Fish Biology 74, pp. 652-668.
Teletchea, F., Gardeur, J.N., Kamler, E., Fontaine, P.
Effects of four factors on the quality of male reproductive cycle in pikeperch Sander lucioperca .
Aquaculture 291 (3-4), pp 217-223
Teletchea, F., Gardeur, J.N., Psenicka, M., Kaspar, V., Le Doré, Y., Linhart, O., Fontaine, P.
Advances in Natural and Applied Sciences, 3 (1), pp. 19-21.
Toudert, N., Djilani, S.E., Djilani, A., Dicko, A., Soulimani, R.
The crude methanolic and butanolic extracts of the aerial parts of Ampelodesma mauritanica were examined for antibacterial and antifungal activity in vitro using the disc diffusion method. Activity against five bacterial strains (gram positive bacteria and gram negative bacteria) and one fungal strain is discussed. Phytochemical screening shows that this plant is particularly rich in flavonoids and saponins which might be responsible for its antimicrobial activity.
Variations in illumination, closed wall transparency and/or extramaze space influence both baseline anxiety and response to diazepam in the rat elevated plus-maze.
Behavioural Brain Research, 203 (1), pp. 35-42.
Violle, N., Balandras, F., Le Roux, Y., Desor, D., Schroeder, H.
Numerous methodological-related variables have been demonstrated to influence the baseline anxiety level of rodents exposed to the elevated plus-maze (EPM), raising questions about the sensitivity of this test for the detection of the effects of anxiolytic drugs. Thus, the present study was designed (1) to assess the combined effects of illumination (40-lx red or white light), closed wall type (walls made of translucent or opaque material) and extramaze space size (small or spacious experimental room) on rat behaviour, and (2) to investigate the effects of such parameters on the relevance of the maze for detecting the effects of diazepam orally administrated at the anxiolytic dose of 3 mg/kg. Results indicate that illumination and closed wall type are two main independent parameters that are able to modify the open arm avoidance. Moreover, the closed wall type interacts with the extramaze space size since the reduction of the open arm exploration induced by opaque closed walls is two-fold stronger in the spacious experimental room than in the small one. Finally, the diazepam anxiolytic activity is significantly detected in our laboratory in specific EPM conditions (maze with opaque walls, use of a red light, maze located in a spacious experimental room). In conclusion, the present study demonstrates that an inappropriate baseline anxiety level due to the methodological use of the EPM can dramatically reduce the sensitivity of the maze for the detection of benzodiazepine-related compounds. This study also provides new insights into the perception of the EPM open space in rats.
Pollution and obesity... where lies the risk?
Obesite, 3 (3), pp. 128-132.
Amoussou, B., Guiavarc'h, Y., Heidi, H., Yen, F., Mejean, L.
The relationship between adipocytes and pollutants does not appear to be limited to molecular storage only, as pollutants follow the movements of fatty acids as they alternate between lipolysis and lipogenesis: an in vitro study in mice confirms that the presence of small quantities of benzoapyrene in the animal\'s food or environment gives rise to significant weight gain from the very first days of exposure. An in vitro study of isolated mouse adipocytes shows that the phenomenon is linked to a malfunction of transmembrane receptors (ß receptors, MC2-R receptors). Recent results suggest that an accumulation of pollutants in the cell membrane might affect the integrity of these particular receptors. The phenomenon\'s ubiquitous nature is also emphasised.
Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France
(2008) Environmental Pollution, 152 (3), pp. 679-685.
Banas, D., Masson, G., Leglize, L., Usseglio-Polatera, P., Boyd, C.E.
Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2-620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L.
Ultrastructural features of hepatocytes in cultured Eurasian perch (Perca fluviatilis L.) as affected by nutritional and husbandry conditions
British Journal of Nutrition, 100 (2), pp. 317-331.
Blanchard, G., Gardeur, J.N., Mathis, N., Brun-Bellut, J., Kestemont, P.
A wide range of factors can be attributed to the syndrome of fatty liver observed in some cultured fish species. The objective of the study was therefore to quantify different hepatocyte ultrastructural features as potentially influenced by twelve nutritional and husbandry factors, in order to discriminate the most influent factors in Eurasian perch (Perca fluviatilis), a typical carnivorous temperate fish species. Twenty-four groups of juveniles (initial weight 57.6 (sd 14.4) g) were intensively reared for 116 d and fed sixteen different isoproteic diets. The distribution of the experimental treatments was based on a multivariate fractional factorial design (L24212) with either high (+1) or low (-1) level of each of the following factors: diet (lipid and protein sources, lipid content, astaxanthin enrichment), feeding level, daily and weekly distribution frequency, fish density, initial weight heterogeneity, temperature, photoperiod, and light spectrum. Liver lipid droplets, glycogen, mitochondria and rough endoplasmic reticulum (RER) were semi-quantified and analysed by a soft imaging system using transmission electronic microscopy photographs. Important variability of hepatocyte ultrastructural features was observed. The present study confirms that the rearing temperature, through its influences in the general metabolic activity, seems to be the main factor modifying mainly lipid droplet accumulation and RER development. However, factors that could be pooled under the designation of factors leading to food accessibility and lipid and protein quality intensify or compensate the effect of temperature. © The Authors 2008.
Journal of Dairy Science., 91 (6) : 2257-2264
Cardot, V., Le Roux, Y., Jurjanz, S.
The water intake of 41 lactating dairy cows managed according to current dairy farm practices was individually and continuously monitored to 1) investigate drinking behavior and 2) determine factors affecting water intake. The cows were housed in a free-stall barn and fed once daily with a corn silage and concentrate-based total mixed ration (48% dry matter content; 20.6 +/- 3.3 kg/d of dry matter intake). Cows were milked twice daily, with a yield of 26.5 +/- 5.9 kg/d. The daily free water intake (FWI) was 83.6 +/- 17.1 L, achieved during 7.3 +/- 2.8 drinking bouts. The drinking bout water intake was 12.9 +/- 5.0 L. Almost three-fourths of the FWI occurred during working hours (0600 to 1900 h). Consumption peaks corresponded to feeding and milking times. More than one quarter of the daily FWI was met during the 2 h after each milking. About 75% of the present cows visited the watering point at least once during the 2 h after the evening milking. It is probable that drinking behavior evolved with lactation, but further studies are required to identify the relationship between lactation stage and drinking behavior. The most relevant factors affecting the daily FWI of lactating cows were best combined according to the following predictive equation: (R(2) = 0.45; n = 41 cows, n = 1,837): FWI, L/d = 1.53 x dry matter intake (kg/d) + 1.33 x milk yield (kg/d) + 0.89 x dry matter content (%) + 0.57 x minimum temperature ( degrees C) - 0.30 x rainfall (mm/d) - 25.65. The results obtained using these equations were in agreement with the equations developed by other researchers.
An atypical catalytic mechanism involving three cysteines of thioredoxin
Journal of Biological Chemistry, 283 (34), pp. 23062-23072.
Cha, S.K., Navrot, N.B., Didierjean, C., Rouhier, N., Hirasawa, M., Knaff, D.B., Wingsle, G., Samian, R., Jacquot, J.-P., Corbier, C., Gelhaye, E.
1-hydroxypyrene in milk and urine as a bioindicator of polycyclic aromatic hydrocarbon exposure of ruminants
Journal of Agricultural and Food Chemistry, 56 (5), pp. 1780-1786.
Chahin, A., Guiavarc'h, Y.P., Dziurla, M.-A., Toussaint, H., Feidt, C., Rychen, G.
Urinary 1-hydroxypyrene (1-OH-pyrene) is now largely considered to be a valuable biomarker of exposure of man and animals to pyrene and other polycyclic aromatic hydrocarbons (PAHs). However, from a practical and agronomic standpoint, the question remains whether such biomarking capability still holds when 1-OH-pyrene is analyzed in milk produced by ruminants. To assess this hypothesis, four goats were daily submitted to three different amounts of pyrene oral ingestion, together with phenanthrene and benzo(a)pyrene (1, 7, and 49 mg/day during 1 week each). An HPLC-fluorometric analysis of 1-OH-pyrene in milk revealed a perfect correlation between pyrene doses and 1-OH-pyrene detected in milk, thus fully confirming the biomarking capability of 1-OH-pyrene and providing information on its transfer coefficient toward milk. Transfer equations such as the ones found in the present study could be used as a valuable and practical risk assessment tool in (i) the accurate monitoring of exposure of ruminants to pyrene and (ii) the evaluation of occupational and environmental exposure of ruminants to PAH mixtures.
Pollution maps of grass contamination by platinum group elements and polycyclic aromatic hydrocarbons from road traffic
Agronomy for Sustainable Development, 28 (4), pp. 457-464.
Dan-Badjo, A.T., Rychen, G., Ducoulombier, C.
The increase in deposition of air pollutants such as the platinum group elements (PGEs) Pt, Pd and Rh, and polycyclic aromatic hydrocarbons (PAHs) from vehicles on plants has raised concerns about the risk for the quality of food and, in turn, for human health. Here, we report the first pollution maps of PGEs and PAHs at the agricultural scale. PGEs have recently emerged in ecosystems due to their massive use as catalysts in the automobile industry. PAHs are combustion by-products known for their carcinogenic properties. PAHs and PGEs emitted by vehicles can enter the food chain through deposition on plants growing near roads. Despite many investigations of PAHs and PGEs, knowledge on their spatial distribution near roads is very scarce. Here, we assessed their localization on the scale of an agricultural field close to a road with 7200 vehicles per day. While classical studies usually involve direct measurements of plants growing in the field, we used an alternative experimental approach to allow an unambiguous assessment of the pollution impact. Ryegrass (Lolium perenne) was first cultivated in pots in a closed greenhouse to isolate the plants from the outdoor atmosphere. Then, ryegrass pots were transferred to the agricultural field. The spatial distribution of PGEs and PAHs was assessed by placing ryegrass pots 0 m, 10 m, 25 m and 50 m from the road. This method thus allowed the measurement of PGE and PAH deposit from vehicle emissions during a known timeframe. After a one-month exposure, the PGE and PAH concentrations in ryegrass samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and high-pressure liquid chromatography (HPLC), respectively. Our results demonstrate a significant effect of pollution by the outdoor atmosphere for Pd and PAHs. Indeed, the concentrations increased by a factor of 1.5 for Pd and by a factor of 7 for PAHs after one month\'s exposure in the isolated pasture. The results also demonstrate clearly the impact of road traffic. Indeed, the highest PGE and PAH concentrations were detected in ryegrass exposed at the road site. Pd and PAH concentrations decreased significantly up to 39% and 60%, respectively, from 0 to 50 m away from the road. The pollution maps show that the maximum depositions occur precisely along the road plan. The highest pollution levels of grasses of 23 ng Pd/g grass and 260 ng PAHs/g grass dry weight were recorded between 0 and 10 m on both sides of the road. Pollution maps should thus help to assess more precisely the impact of road traffic on food quality.
Molecular typing of industrial strains of Pseudomonas spp. isolated from milk and genetical and biochemical characterization of an extracellular protease produced by one of them
International Journal of Food Microbiology, 125 (2), pp. 188-196.
Dufour, D., Nicodème, M., Perrin, C., Driou, A., Brusseaux, E., Humbert, G., Gaillard, J.-L., Dary, A.
Transfer of phenanthrene and its hydroxylated metabolites to milk, urine and faeces
Polycyclic Aromatic Compounds, 28 (2), pp. 98-111.
Grova, N., Feidt, C., Monteau, F., Le Bizec, B., Rychen, G.
Single oral ingestion of phenanthrene was administered in lactating goats with the aim of characterizing its behavior and its biotransformation in milk and other excretion products. Detection and identification of the analytes (phenanthrene, 1-, 2-, 3-, 4-, 9-hydroxyphenanthrene and 9,10- dihydroxyphenanthrene) were achieved using GC-MS procedure. The blood kinetics revealed the presence of phenanthrene and its hydroxylated forms quite soon (3-7 h) after the oral administration. The high concentration of metabolites in blood (3-300 ng/mL) suggests a very fast biotransformation process of phenanthrene. A direct link between the lipophily and the presence of the molecule in milk or urine was established. Indeed, 94% and 99.6% of the excreted phenanthrene were recovered under metabolite forms in milk and urine respectively. The non-metabolized phenanthrene was principally found in faeces. The more the solubility increased, the more the compound was transferred through milk and urine; as a consequence, the 9,10-diOHphenanthrene appeared mainly in urine whereas phenanthrene was practically not detectable. These results provide original information on the ability of the dairy ruminant to metabolize and to transfer phenanthrene. The extremely low rate transfer of phenanthrene and its metabolites to the milk (0.25%) should not, therefore, be considered as a major health concern.
Sub-acute administration of benzo[a]pyrene (B[a]P) reduces anxiety-related behaviour in adult mice and modulates regional expression of N-methyl-d-aspartate (NMDA) receptors genes in relevant brain regions
Chemosphere, 73 (1 SUPPL.), pp. S295-S302.
Grova, N., Schroeder, H., Farinelle, S., Prodhomme, E., Valley, A., Muller, C.P.
Abnormal glutamatergic transmission caused by modulation of N-methyl-d-aspartate (NMDA) receptors was demonstrated in animal models chronically exposed to various organic micropollutants. Recent developments in neurobiology have implicated these receptors in the regulation of anxiety. In order to investigate anxiety-related effects of benzo[a]pyrene (B[a]P), Balb/c mice were sub-acutely exposed to B[a]P (0.02-200 mg kg-1 day-1, 10 days, i.p.). Their performance was tested in the elevated-plus maze and the hole-board apparatus and the NMDA receptor expression genes (NR1, 2A and 2B subunits) was measured in eight brain regions. Mice treated with 20-200 mg kg-1 B[a]P showed a disproportionate accumulation of B[a]P and its metabolites (in particular, the toxic 7,8-diol-B[a]P) in the blood and even more in the brain. These mice were less anxious than controls in the hole-board test and the elevated-plus maze. This observation was associated with an overexpression of the NMDA NR1 receptor gene and concomitant decreases of the NR2A and NR2B subunits expression in the hippocampus, the hypothalamus and the cerebellum. In the temporal cortex, a significant dose-related decrease of NR2A was observed whereas the other subunits remained unchanged. In conclusion, a sub-acute exposure to B[a]P (20 and 200 mg kg-1) reduced anxiety-related behaviour in adult mice and concomitantly impaired NMDA receptor gene expression in relevant brain regions.
Interfacial approach to polyaromatic hydrocarbon toxicity: Phosphoglyceride and cholesterol monolayer response to phenantrene, anthracene, pyrene, chrysene, and benzo[a]pyrene
Journal of Physical Chemistry B, 112 (43), pp. 13518-13531.
Korchowiec, B., Corvis, Y., Viitala, T., Feidt, C., Guiavarch, Y., Corbier, C., Rogalska, E.
Interactions of phenantrene, anthracene, pyrene, chrysene, and benzo[a]pyrene (polyaromatic hydrocarbons) with model phospholipid membranes were probed using the Langmuir technique. The lipid monolayers were prepared using 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, 1,2-dipalmitoyl-sn-glycero-3- phosphoethano-lamine, 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol, 1,2-dipalmitoyl-sn-glycero-3-phosphoserine, 1,2-myristoyl-sn-glycero-3- phosphoethanolamine, 1,2-dilauroyl-sn-glycero-3-phosphocholine, and cholesterol. Surface pressure and electrical surface potential were measured on mixed phospholipid/PAH monolayers spread on a pure water subphase. The morphology of the mixed monolayers was followed with Brewster angle microscopy. Polarization-modulation infrared reflection-absorption spectroscopy spectra obtained on DPPE/benzo[a]pyrene showed that the latter interacts with the carbonyl groups of the phospholipid. On the other hand, the activity of phospholipase A2 toward DLPC used as a probe to locate benzo[a]pyrene in the monolayers indicates that the polyaromatic hydrocarbons are not accessible to the enzyme. The results obtained show that all PAHs studied affect the properties of the pure lipid, albeit in different ways. The most notable effects, namely, film fluidization and morphology changes, were observed with benzo[a]pyrene. In contrast, the complexity of mixed lipid monolayers makes the effect of PAHs difficult to detect. It can be assumed that the differences observed between PAHs in monolayers correlate with their toxicity.
Direct determination of recombinant bovine somatotropin in plasma from a treated goat by liquid chromatography/high-resolution mass spectrometry.
Rapid communications in mass spectrometry, 22 (20), pp. 3130-3136.
Le Breton, M.H., Rochereau-Roulet, S., Pinel, G., Bailly-Chouriberry, L., Rychen, G., Jurjanz, S., Goldmann, T., Le Bizec, B.
Recombinant bovine somatotropin (rbST) is used in dairy cattle to enhance milk production. Despite the ban on this hormone in some countries, especially in Europe, there is so far no method available for the direct detection of rbST either in milk or in plasma. An analytical strategy has been developed to analyze rbST in plasma, including a purification procedure based on a precipitation with ammonium sulphate, followed by a solid-phase extraction (SPE)-based clean-up on C4 sorbent and precipitation with cold methanol. The hormone was then digested with trypsin and analyzed by liquid chromatography/high-resolution mass spectrometry (LC/HRMSn) on a linear ion trap coupled with an Orbitrap. The tryptic N-terminal peptide, specific to the difference between the endogenous and recombinant form of the somatotropin, was fragmented and product ions were analyzed at high mass resolution. Applying this approach to goat plasma allowed the direct detection of 10 ng mL(-1) of rbST in fortified samples. It also showed the presence of rbST in plasma collected from a goat treated with the hormone, even 2 days after administration. These results are of a great interest in the field of somatotropin control and undoubtedly constitute a first step in the development of a method for the detection of rbST not only in bovine plasma, but also in other biological matrices such as milk.
Effects of reduced dietary calcium and phytase supplementation on calcium and phosphorus utilisation in broilers with modified mineral status
British Poultry Science, 49 (6), pp. 705-715.
Letourneau-Montminy, M.P., Lescoat, P., Narcy, A., Sauvant, D., Bernier, J.F., Magnin, M., Pomar, C., Nys, Y., Jondreville, C.
The impact of modified mineral status and dietary Ca:P ratio on Ca and P utilisation was measured in chicks with or without phytase supplementation. In a preliminary study, 4 diets were given to chicks from 3 to 15 d of age: D1 (65 g P/kg and Ca:P = 15) and D2, D3 and D4 (60, 54 and 50 g P/kg, respectively, and Ca:P = 12). Growth performance was similar across diets. Tibia ash was similar in chicks given D1 and D2, but was gradually depressed from D2 to D4 (-22%). In the depletion period, two groups of chicks, with similar performance, but with different mineral status were achieved by feeding them, from 5 to 15 d of age, diets with a similar Ca:P ratio of 12, but containing 63 or 52 g P/kg. During the subsequent 11 d of the repletion period, chicks from each of the two previous groups were given one of the 4 diets containing 57 g P/kg, but differing in their Ca (83 and 53 g Ca/kg) and microbial phytase (0 or 1000 FTU, Natuphos) levels in a 2 2 2 factorial arrangement. At the end of the repletion period, the initially depleted chicks could not be differentiated from the non-depleted chicks, indicating the capacity of chicks to compensate for their initial depleted mineral status. Interaction between dietary Ca and phytase levels was not significant. Phytase improved growth performance and bone characteristics. Reduced dietary Ca enhanced feed intake and growth rate, but depressed bone dry matter and ash weight. At the end, diets supplemented with phytase maximised bone ash weight when chicks were fed with a Ca:P ratio of 15 but elicited the highest growth rate when chicks were fed with a Ca:P ratio of 09.
Les populations de poissons dans le réservoir du Mirgenbach (1986-2006, CNPE Cattenom, France) : un modèle pour l’étude des effets d’un changement thermique global ?
Hydroécologie Appliquée, 16, pp. 135-167.
Masson, G., Demski, S., Staffolani, F., Wagner, P., Valente, E., Maazouzi, C., Banas, D., Poinssaint, J.F., Pihan, J.C.
Productions Animales, 21 (1), pp. 79-96.
Meschy, F., Jondreville, C., Dourmad, J.Y., Narcy, A., Nys, Y.
The effects of Garum Armoricum® (GA) on elevated-plus maze and conditioned light extinction tests in rats
Current Topics in Nutraceutical Research, 6 (1), pp. 41-45.
Messaoudi, M., Lalonde, R., Nejdi, A., Bisson, J.-F., Rozan, P., Javelot, H., Schroeder, H.
Garum Armoricum® (GA), a compound rich in polyunsaturated fatty acids, free amino acids, small peptides, vitamins and minerals, was evaluated on two fear-related assays in rats. GA and diazepam (DZP) increased entries into open arms relative to placebo, as well as percentage of open arm entries in the elevated plus-maze test. In a similar fashion, all drugged groups spent more time inside the open arms and less time inside the enclosed arms. After a two-day period of conditioned avoidance learning of an aversive bright light, GA and vehicle groups successfully discriminated the active from the inactive lever. On the initial day of acquisition, GA and piracetam (PIR) groups achieved successful discrimination though the control group did not. These results indicate that GA may have anxiolytic-like effects without causing learning deficiencies. These psychotropic properties of GA may be due to the synergistic action of its active constituents.
Reprod. Biol. Endocrinol. 2008, 6:19.
Milla S., Terrien X., Ibrahim F., Fiet J., Giton J., Prunet P., Le Gac F.
Trapping of the thioacylglyceraldehyde-3-phosphate dehydrogenase intermediate from Bacillus stearothermophilus: Direct evidence for a flip-flop mechanism
Journal of Biological Chemistry, 283 (31), pp. 21693-21702
Moniot, S., Bruno, S., Vonrhein, C., Didierjean, C., Boschi-Muller, S., Vas, M., Bricogne, G., Branlant, G., Mozzarelli, A., Corbier, C.
The effect of microbial phytase on true and apparent ileal amino acid digestibilities in growing-finishing pigs
Journal of Animal Science, 86 (7), pp. 1598-1608.
Pomar, C., Gagne, F., Matte, J.J., Barnett, G., Jondreville, C.
Ten 56-d-old, 15-kg barrows were surgically fitted with a postvalvular T-cecum cannula at the ileo-cecal junction to evaluate the effect of microbial phytase on apparent and true ileal AA digestibility and N utilization. A semipurified cornstarch- and soybean meal-based diet was formulated to contain 3.4 Mcal of DE/kg, 17.0% CP, 0.8% Ca, and 0.6% P but had a low phytate-P concentration (0.13%; all on an as-fed basis). Chromic oxide and dysprosium chloride were used as indigestible markers. The basal diet was supplemented with O or 1,000 phytase units/kg of microbial phytase. Postprandial plasma urea N and α-amino N concentrations, excretion of Ca, P, and N in feces and urine, and ileal AA digestibilities were determined 3 times at 4-wk intervals beginning at 70 d of age. The homoarginine (HA) method was used to determine endogenous AA flow by replacing 50% of the basal protein with guanidinated protein. Microbial phytase had no effect on apparent ileal digestibility (AID) or on true ileal digestibilities of N and most AA but did increase AID for arginine (P = 0.006) and methionine (P = 0.037). However, in HA diets, phytase increased the AID of CP (P = 0.01) and several AA. Addition of microbial phytase had no effect on the postprandial α-amino N concentrations in plasma but increased overall plasma urea N concentrations (P = 0.035). Barrows fed phytase-supplemented diets had decreased P in feces (P = 0.003) and greater P in urine (P = 0.001) but comparable total P excretion compared with barrows fed no phytase-supplemented diets. In conclusion, the addition of phytase to a semi-purified soybean meal-based diet did not affect the AID of several AA. In addition, differences between the basal and HA diets in N digestibilities indicated that that guanidination may limit the use of the HA method in determining endogenous protein losses.
Effect of organic and inorganic selenium sources in sow diets on colostrum production and piglet response to a poor sanitary environment after weaning
Animal, 2 (6), pp. 859-866.
Quesnel, H., Renaudin, A., Le Floc'h, N., Jondreville, C., Pere, M.C., Taylor-Pickard, J.A., Le Dividich, J.
The objectives of this study were to determine the effect of the chemical form of selenium (Se) fed to sows (1) on production and immune quality of colostrum and (2) on piglet response to a deterioration of sanitary conditions after weaning. Twenty-two pregnant sows were assigned to receive a diet supplemented with 0.3 ppm Se from either sodium selenite (inorganic Se) or Se-enriched yeast (organic Se as Sel-Plex® Alltech Inc., Nicholasville, KY, USA). Dietary treatments were applied during the last month of pregnancy and lactation. Blood samples were collected on sows before dietary treatment, on the day of weaning and 6 weeks later, and on three to five piglets within litters at birth, at weaning and 6 weeks post weaning. Whole blood was analysed for Se concentration. Colostrum samples were collected at 0, 3, 6 and 24 h post partum and milk samples on days 14 and 27 of lactation. Colostrum and milk were analysed for Se and immunoglobulin G (IgG) concentrations. At weaning, 40 pairs of littermate piglets were moved to rooms where sanitary conditions were good or purposely deteriorated. Piglets were reared individually and fed ad libitum. After 15 days, piglets and feed refusals were weighed and a blood sample was collected to measure plasma haptoglobin concentration. When sows were fed organic Se, Se concentrations were increased by 33% in colostrum (P < 0.05), 89% in milk (P < 0.001) and by 28% in whole blood of piglets at weaning (P < 0.001). Colostrum production during the 24 h after the onset of farrowing and IgG concentrations in colostrum and milk did not significantly differ between the two groups of sows. Weaned piglets reared in good sanitary conditions grew faster (P < 0.001) than piglets housed in poor conditions. Sanitary conditions did not influence mean plasma haptoglobin concentrations of piglets (P > 0.1). The source of Se fed to the dams did not influence piglet performance or haptoglobin concentrations after weaning. These findings confirm that, compared with inorganic Se, organic Se fed to the dam is better transferred to colostrum and milk, and consequently to piglets. They indicate that the Se source influences neither colostrum production nor IgG concentrations in colostrum, and that the higher Se contents of piglets does not limit the reduction of growth performance when weaning occurs in experimentally deteriorated sanitary conditions.
Effects of lifelong intervention with an oligofructose-enriched inulin in rats on general health and lifespan.
British Journal of Nutrition 100 (6), pp. 1192-1199.
Rozan, P., Nejdi, A., Hidalgo, S., Bisson, J.F., Desor, D., Messaoudi. M.
Dairy ruminant exposure to persistent organic pollutants and excretion to milk
Animal, 2 (2), pp. 312-323.
Rychen, G., Jurjanz, S., Toussaint, H., Feidt, C.
Human activities produce polluting compounds such as persistent organic pollutants (POPs), which may interact with agriculture. These molecules have raised concern about the risk of transfer through the food chain via the animal product. POPs are characterised by a strong persistence in the environment, a high volatility and a lipophilicity, which lead to their accumulation in fat tissues. These compounds are listed in international conventions to organise the information about their potential toxicity for humans and the environment. The aim of this paper is to synthesise current information on dairy ruminant exposure to POPs and the risk of their transfer to milk. Three major groups of POPs have been considered: the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), the polychlorobiphenyls (PCBs) and the polycyclic aromatic hydrocarbons (PAHs). The results show that contamination of fodder and soil by these compounds is observed when they are exposed to emission sources (steelworks, cementworks, waste incinerators or motorways) compared with remote areas. In general, soil contamination is considered higher than plant contamination. Highest concentrations of POPs in soil may be close to 1000 ng/kg dry matter (DM) for PCDD/Fs, to 10 000 mg/kg DM for PAHs and 100 μg/kg DM for PCBs. The contamination of milk by POPs depends on environmental factors, factors related to the rearing system (fodder and potentially contaminated soil, stage of lactation, medical state of the herd) and of the characteristics of the contaminants. Transfer rates to milk have been established: for PCBs the rate of transfer varies from 5% to 90%, for PCDD/Fs from 1% to 40% and for PAHs from 0.5% to 8%. The differential transfer of the compounds towards milk is related to the hydrophobicity of the pollutants as well as to the metabolic susceptibility of the compounds.
Comparative analysis of reproductive strategies of European fishes: applications to the domestication of species in aquaculture.
Cybium 32, pp. 300-302.
Teletchea F., Fostier A., Kamler E., Gardeur J.N., Le Bail P.Y., Jalabert B., Fontaine P.
In: Proceedings of the 8th International Symposium on Reproductive Physiology of Fish (Equipe “Reproduction des Poissons”, INRA, Ed), Cybium, 32 (2 suppl.), 192-193.
Wang N., Rodina M., Gardeur J.-N., Vuillard J.-T., Policar T., Henrotte E., Mandiki R., Kestemont P., Linhart O., Fontaine P.
Namur (Belgique) 23-24 Janvier 2008 Presses Universitaires de Namur. 150 pp
Fontaine P., Kestemont P., Teletchea F., Wang N.
In: Aquaculture explained: Farming o Eurasian perch. Vol. 1: Juvenile production. Irish Sea Fisheries Board publivation 24, pp 16-21.
Fontaine P., Kestemont P., Melard C.
In: Aquaculture explained: Farming o Eurasian perch. Vol. 1: Juvenile production. Irish Sea Fisheries Board publivation 24, pp 12-15.
Rougeot C., Fontaine P., Mendiki S.M.N.
Gestational vitamin B deficiency leads to homocysteine-associated brain apoptosis and alters neurobehavioral development in rats
American Journal of Pathology, 170 (2), pp. 667-679.
Blaise, S.A., Nedelec, E., Schroeder, H., Alberto, J.-M., Bossenmeyer-Pourie, C., Gueant, J.-L., Daval, J.-L.
Hyperhomocysteinemia has been identified as a risk factor for neurological disorders. To study the influence of early deficiency in nutritional determinants of hyperhomocysteinemia on the developing rat brain, dams were fed a standard diet or a diet lacking methyl groups during gestation and lactation. Homocysteinemia progressively increased in the offspring of the deficient group and at 21 days reached 13.3 ± 3.7 µmol/L versus 6.8 ± 0.3 µmol/L in controls. Homocysteine accumulated in both neurons and astrocytes of selective brain structures including the hippocampus, the cerebellum, the striatum, and the neurogenic subventricular zone. Most homocysteine-positive cells expressed p53 and displayed fragmented DNA indicative of apoptosis. Righting reflex and negative geotaxis revealed a delay in the onset of integration capacities in the deficient group. Between 19 and 21 days, a poorer success score was recorded in deficient animals in a locomotor coordination test. A switch to normal food after weaning allowed restoration of normal homocysteinemia. Nevertheless, at 80 days of age, the exploratory behavior in the elevated-plus maze and the learning and memory behavior in the eight-arm maze revealed that early vitamin B deprivation is associated with persistent functional disabilities, possibly resulting from the ensuing neurotoxic effects of homocysteine.
Impact of nutrition on nitrogen, phosphorus, Cu and Zn in pig manure, and on emissions of ammonia and odours
Livestock Science, 112 (3), pp. 192-198.
Dourmad, J.-Y., Jondreville, C.
Platinum and Palladium transfer to milk, organs and tissues after a single oral administration to lactating goats
Chemosphere, 68 (4), pp. 712-715.
Ducoulombier-Crepineau, C., Feidt, C., Rychen, G.
Milk-clotting activity of enzyme extracts from sunflower and albizia seeds and specific hydrolysis of bovine kappa-casein
International Dairy Journal, 17 (7), pp. 816-825.
Egito, A.S., Girardet, J.-M., Laguna, L.E., Poirson, C., Molle, D., Miclo, L., Humbert, G., Gaillard, J.-L.
Milk-clotting activity found in ammonium sulfate-precipitated protein extracts from Albizia lebbeck and Helianthus annuus seeds was studied. Specific clotting activity of albizia seed extract was 15 times higher than that of sunflower seed extract. Zymogram analysis revealed several proteolytic bands in albizia seed extract and one diffuse proteolytic band for sunflower seed extract. Whole bovine casein was incubated with the plant seed extracts or chymosin and some breakdown products were characterized by reversed-phase high-performance liquid chromatography and electrophoresis. Similar to chymosin, the two seed extracts exhibited proteolytic activity toward κ-casein, αs-casein and β-casein, with the highest activity observed for the albizia seed extract. Mass spectrometry analysis showed that the sunflower extract hydrolyzed κ-casein at the Phe105–Met106 bond, as does chymosin. The albizia extract also displayed activity on κ-casein, but the Lys116–Thr117 bond was its preferred target.
Characterisation of whey proteins of camel (Camelus dromedarius) milk and colostrum
Small Ruminant Research, 70 (2-3), pp. 267-271.
El-Hatmi, H., Girardet, J.-M., Gaillard, J.-L., Yahyaoui, M.H., Attia, H.
Simultaneous effects of nutritional and environmental factors on growth and flesh quality of Perca fluviatilis using a fractional factorial design study
Aquaculture, 273 (1), pp. 50-63.
Gardeur, J.-N., Mathis, N., Kobilinsky, A., Brun-Bellut, J.
Implication of stringent response in the increase of mutability of the whiG and whiH genes during Streptomyces coelicolor development
Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 624 (1-2), pp. 49-60.
Genay, M., Decaris, B., Dary, A.
Modulation of behavior and NMDA-R1 gene mRNA expression in adult female mice after sub-acute administration of benzo(a)pyrene
NeuroToxicology, 28 (3), pp. 630-636.
Grova, N., Valley, A., Turner, J.D., Morel, A., Muller, C.P., Schroeder, H.
The behavioral performances of adult mice exposed to sub-acute doses of benzo(a)pyrene (B(a)P) were monitored in tests related to learning and memory (Y maze and Morris water maze), locomotor activity (open-field test) and motor coordination (Locotronic apparatus). At low doses (0.02 and 0.2 mg/kg), B(a)P impaired short-term learning and spatial memory performance in the Y maze and in the Morris water maze tests. Surprisingly, in the Y maze, the performances of animals exposed to the highest dose of B(a)P (200 mg/kg) were quite similar to those of control animals. Hyperactivity/hyperarousal observed in both tests at this dose and attributed to an anxiolytic-like effect of B(a)P may have blurred the learning deficit in these mice faced with a new situation. These deficits seem to be unrelated to motor impairments because B(a)P had no effect on locomotor activity and motor coordination. We demonstrated that sub-acute exposure to B(a)P in adult mice also modulates gene expression of NMDA-R1 subunit in brain areas highly involved in cognitive function like the hippocampus, suggesting a relationship between the expression of functional NMDA-R1 mRNA, impairment of short-term and spatial memory and the B(a)P exposure levels.
Improvement of the ammonia measurement using a clarifying reagent and application to evaluate heat damage in commercial milk samples
International Dairy Journal, 17 (8), pp. 902-906
Humbert, G., Guingamp, M.-F., Gaillard, J.-L.
Characterisation of European varieties of triticale with special emphasis on the ability of plant phytase to improve phytate phosphorus availability to chickens
British Poultry Science, 48 (6), pp. 678-689.
Jondreville, C., Genthon, C., Bouguennec, A., Carre, B., Nys, Y.
Sparing effect of microbial phytase on zinc supplementation in maize-soya-bean meal diets for chickens
Animal, 1 (6), pp. 804-811.
Jondreville, C., Lescoat, P., Magnin, M., Feuerstein, D., Gruenberg, B., Nys, Y.
Journal of Agricultural and Food Chemistry, 55 (21), pp. 8800-8805.
Jurjanz, S., Rychen, G.
Efficacy of alpha s1-casein hydrolysate on stress-related symptoms in women.
European Journal of Clinical Nutrition 61 (4), pp. 536-541.
Kim, J.H., Desor, D., Kim, Y.T., Yoon, W.J., Kim, K.S., Jun, J.S., Pyun, K.H., Shim, I.
Crystal Structures of a Poplar Thioredoxin Peroxidase that Exhibits the Structure of Glutathione Peroxidases: Insights into Redox-driven Conformational Changes
Journal of Molecular Biology, 370 (3), pp. 512-529.
Koh, C.S., Didierjean, C., Navrot, N., Panjikar, S., Mulliert, G., Rouhier, N., Jacquot, J.-P., Aubry, A., Shawkataly, O., Corbier, C.
Milk and urine excretion of polycyclic aromatic hydrocarbons and their hydroxylated metabolites after a single oral administration in ruminants
Journal of Dairy Science, 90 (6), pp. 2624-2629.
Lapole, D., Rychen, G., Grova, N., Monteau, F., Le Bizec, B., Feidt, C.
Effects of dietary factors, stocking biomass and domestication on the nutritional and technological quality of the Eurasian perch Perca fluviatilis
Aquaculture, 262 (1), pp. 86-94.
Mairesse, G., Thomas, M., Gardeur, J.-N., Brun-Bellut, J.
Potential animal-centred indicators of dairy goat welfare.
Animal Welfare 16 (2), pp. 161-164.
Mazurek, M., Marie, M., Desor, D.
Staphylococcus aureus related mammary infection in cows: Correlation between somatic cell count and proteolysis during early and chronic phase of infection
Journal of Animal and Feed Sciences, 16, Suppl. 1, pp. 117–129.
Michelutti I., Haddadi K. and Y. Le Roux
Experimental mastitis induced by the S. aureus in six dairy cows was performed to investigate the relationship between somatic cell count (SCC) and proteolysis during early and chronic phase of infection (up to 28 days post-infection). An elevated level of infection was detected during the early phase and was characterized by a measurable link between SCC and proteose-peptone content. In contrast to this observation, no significant relationship was detectable between the two parameters during the chronic phase of infection. During this phase the measurement of SCC could not be established as a reliable indicator of milk proteolysis. Moreover, the results of this study demonstrated that the high risk of milk proteolysis associated with an elevated SCC content does not consistently obey the opinion that excessive SCC results in a high level of proteolysis of milk. Our results were compared with experimental E. coli mastitis in order to evaluate the differences that exist between the courses of bovine intramammary infection caused by S. aureus and E. coli.
The primary structure of a low-Mr multiphosphorylated variant of beta-casein in equine milk
Proteomics, 7 (8), pp. 1327-1335.
Miclo, L., Girardet, J.-M., Egito, A.S., Mollé, D., Martin, P., Gaillard, J.-L.
Highly phosphorylated casein with a low molecular mass was isolated from Haflinger mare\'s milk by RP-HPLC. It accounts for 4.0% of the casein content. Its mass was determined by LC-ESI-MS before and after treatment by alkaline phosphatase. The molecular mass found for the apo-form (10 591 ± 2 Da) is in agreement with its primary structure, which was established by ESI-MS/MS from tryptic peptides. It appeared that this short protein (94 amino acid residues) is an internally truncated form of the full-length equine ![\"\"](\"http://www3.interscience.wiley.com/giflibrary/12/beta.gif\")
-casein (226 residues). This low-Mr variant of equine -casein displays a large deletion (residues 50-181), due to a cryptic splice site usage occurring within exon 7 during the course of primary transcripts processing. The phosphorylation pattern of this equine -casein variant was investigated by LC-ESI-MS and 2-DE. Seven phosphorylation forms were identified with one to seven phosphate groups with pIs ranging between 4.67 and 4.01. The major isoforms carry five and six phosphate groups.
Fr. Peche Pisc. 384, 27-38.
Milla S., Sambroni E., Jalabert B.
Vaccine, 25 (15), pp. 2919-2929.
Roussel, Y., Harris, A., Lee, M.H., Wilks, M.
Deposition of platinum group elements and polycyclic aromatic hydrocarbons on ryegrass exposed to vehicular traffic
Agronomy for Sustainable Development, 27 (3), pp. 261-266.
Tankari Dan-Badjo, A., Ducoulombier-Crepineau, C., Soligot, C., Feidt, C., Rychen, G.
STOREFISH: A new database dedicated to the reproduction of temperate freshwater teleost fishes
Cybium, 31 (2), pp. 227-235.
Teletchea, F., Fostier, A., Le Bail, P.-Y., Jalabert, B., Gardeur, J.-N., Fontaine, P.
Potential of a Pycnoporus sanguineus laccase in bioremediation of wastewater and kinetic activation in the presence of an anthraquinonic acid dye
Enzyme and Microbial Technology, 41 (3), pp. 368-376.
Trovaslet, M., Enaud, E., Guiavarc'h, Y., Corbisier, A.-M., Vanhulle, S.
In the frame of the development of a bioprocess using the competences of White Rot Fungi to decolourise and detoxify dye contaminated effluents, laccases were produced by the strain Pycnoporus sanguineus MUCL 41582 in a malt extract medium. Two isoenzymes were detected among which LAC-1 was concentrated. A survey of the composition of industrial effluents showed that wastewaters from textile industry usually contain high concentrations of Na2SO4 or NaCl. Regarding the activity profile of the biocatalyst against pH, salts, temperature and target substrates, LAC-1 appears to be a good candidate for application in acid dye bath treatments. Studying the model anthraquinonic dye ABu62 decolourisation, we proved that this dye was a good substrate for LAC-1. Furthermore, unusual kinetic behaviour was observed suggesting that LAC-1 was activated in presence of ABu62. On the contrary, a classical Michaelis-Menten behaviour was observed for the oxidation of ABTS and LAC-1 showed a high affinity for this substrate as compared to data available for other laccases. To our knowledge, this is the first report showing this atypical behaviour of a laccase in the presence of dyes.
Stable isotope variability in tissues of the Eurasian perch Perca fluviatilis.
Comparative Biochemistry and Physiology, 148 (3), pp. 504-509.
Vollaire, Y., Banas, D., Thomas, M., Roche, H.
A new type of sediment trap, which overcomes a methodological gap in the study of sedimentation fluxes in shallow lentic systems, is described. The sedimentation rates measured in the field with these new traps were compared with those from other plate and cylindrical traps. As do other plate traps, the new traps allow the resuspension of deposited particles observed on bottom sediments. Furthermore, the new traps do not disturb particle sedimentation on the collecting area and allow to collect the net sedimentation rates in lentic systems.
Teletchea F., Fontaine P.
Biomarker responses in European eel (Anguilla anguilla) exposed to persistent organic pollutants. A field study in the Vaccarès lagoon (Camargue, France).
Chemosphere, 65 (10), pp. 1846-1858.
Buet, A., Banas, D., Vollaire, Y., Coulet, E., Roche, H.
A screening of relevant biomarkers was carried out in order to evaluate metabolic and cellular damages in European eels exposed to a non-point source contamination by persistent organic pollutants (POP) such as polycyclic aromatic hydrocarbons (PAH) and organochlorine compounds (OC) in a protected area, the Nature Reserve of Camargue (France). Investigations were focused on metabolic responses including detoxification mechanisms (biotransformation, antioxidant process), energy requirements and enzymatic membrane markers either involved in neuronal conduction (acetylcholinesterase, AChE) or in osmoregulation and energy metabolism (ATPases). The hepatic and muscular glycogen rates seemed to be suitable biomarkers as well as three hepatic activities involved in the protection against oxyradicals: catalase, glutathione peroxidase (SeGPx) and superoxide dismutases (SOD). The muscle and gill ATPases as well as the muscle and brain AChE showed more significant relevance in terms of biomarkers than the biotransformation enzymes: ethoxyresorufine-O-deethylase (EROD) and uridine diphospho-glucuronyl transferase (UDPGT). However, most of these enzymatic activities depend on numerous abiotic factors, which must be taken into account in such a biomarker assessment approach. Our study provides some conclusive elements to approve the use in situ of biomarkers developed from laboratory studies. It also raises a question regarding the location of contaminant impregnation in fish organ, in relation with age, development status or mode of contamination, and its influence on biomarker response. If the relevance of membrane indicators is confirmed, this study provides an original statement of the extent of the ecotoxicological threat for the aquatic species in a protected area, due to the occurrence of POP in the cell membranes.
PCDD/F and PCB transfer to milk in goats exposed to a long-term intake of contaminated hay
Chemosphere, 64 (4), pp. 650-657.
Costera, A., Feidt, C., Marchand, P., Bizec, B.L., Rychen, G.
Peptides with functional activities of milk | [Les peptides à activités fonctionnelles du lait].
Pratiques en Nutrition (8), pp. 63-65.
Desor, D.
The first crystal structure of a thioacylenzyme intermediate in the ALDH family: New coenzyme conformation and relevance to catalysis
Biochemistry, 45 (9), pp. 2978-2986.
D'Ambrosio, K., Pailot, A., Talfournier, F., Didierjean, C., Benedetti, E., Aubry, A., Branlant, G., Corbier, C.
Fast electrophoretic detection method of adulteration of caprine milk by bovine milk
Arquivo Brasileiro de Medicina Veterinaria e Zootecnia, 58 (5), pp. 932-939.
Egito, A.S., Rosinha, G.M.S., Laguna, L.E., Miclo, L., Girardet, J.M., Gaillard, J.L.
Influence of pre-inductive photoperiod variations on Eurasian perch Perca fluviatilis broodstock response to an inductive photothermal program.
Aquaculture, 255, pp. 410-416.
Fontaine P., Pereira C., Wang N., Marie M.
Genetic instability of whiG gene during the aerial mycelium development of Streptomyces ambofaciens ATCC23877 under different conditions of nitrogen limitations
Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 595 (1-2), pp. 80-90.
Genay, M., Catakli, S., Kleinclauss, A., Andrieux, A., Decaris, B., Dary, A.
Proteomics, 6 (12), pp. 3707-3717.
Girardet, J.-M., Miclo, L., Florent, S., Mollé, D., Gaillard, J.-L.
-Casein was isolated from Haflinger mare\'s milk by RP-HPLC, and displayed microheterogeneity by urea-electrophoresis and 2-DE probably due to a variable degree of phosphorylation. To investigate the degree of phosphorylation, the primary structure of equine -casein was determined by tryptic hydrolysis and MS of peptides released and by MS of the protein treated by alkaline phosphatase. The molecular mass found for the apo-form of Haflinger mare\'s -casein (25 514 ± 3 Da) was close to the theoretical mass of the reported sequence (GenBank AAG43954) modified by insertion of a region (residues 27-34) encoded by an exon sometimes out-spliced (25 511.40 Da). Hence, the -casein isolated from Haflinger mare\'s milk corresponded to a variant of 226 amino acid residues. The latter was composed by highly multi-phosphorylated isoforms with three to seven phosphate groups, and pIs, determined by 2-DE, ranging from 4.74 to 5.30. Moreover, the equine -casein was able to deamidate spontaneously, at the level of Asn in the potential deamidation motif 135Asn-Gly136. Approximately 80% of the protein was deamidated after 96 h of incubation under physiological conditions.
Effect of oral exposure to polycyclic aromatic hydrocarbons on goat's milk contamination
Agronomy for Sustainable Development, 26 (3), pp. 195-199.
Grova, N., Rychen, G., Monteau, F., Le Bizec, B., Feidt, C.
Polymorphonuclear neutrophils and Escherichia coli proteases involved in proteolysis of casein during experimental E. coli mastitis
International Dairy Journal, 16 (6), pp. 639-647.
Haddadi, K., Prin-Mathieu, C., Moussaoui, F., Faure, G.C., Vangroenweghe, F., Burvenich, C., Le Roux, Y.
Helicobacter, 11 (2), pp. 113-122.
Hatzifoti, C., Roussel, Y., Harris, A.G., Wren, B.W., Morrow, J.W., Bajaj-Elliott, M.
Journal of Dairy Research, 73 (4), pp. 464-471.
Humbert, G., Guingamp, M.-F., Linden, G., Gaillard, J.-L.
Importance of sanitary environment for growth performance and plasma nutrient homeostasis during the post-weaning period in piglets
Archives of Animal Nutrition, 60 (1), pp. 23-34.
Le Floc'h, N., Jondreville, C., Matte, J.J., Seve, B.
Journal of Agricultural and Food Chemistry, 54 (1), pp. 263-268.
Lutz, S., Feidt, C., Monteau, F., Rychen, G., Le Bizec, B., Jurjanz, S.
Effects of geographic source, rearing system, and season on the nutritional quality of wild and farmed Perca fluviatilis.
Lipids, 41 (3), pp. 221-229.
Mairesse, G., Thomas, M., Gardeur, J.-N., Brun-Bellut, J.
Influence of photoperiod on reproductive performances in Eurasian perch Perca fluviatilis
Aquaculture, 252 (2-4), pp. 385-393.
Migaud, H., Wang, N., Gardeur, J.-N., Fontaine, P.
J. Exp. Biol. 209, 1147-1156
Milla S., Jalabert B., Rime H., Prunet P., Bobe J.
Proteolysis of bovine alpha-lactalbumin by thermolysin during thermal denaturation
International Dairy Journal, 16 (10), pp. 1157-1167.
N'Negue, M.-A., Miclo, L., Girardet, J.-M., Campagna, S., Molle, D., Gaillard, J.-L.
Thermolysin was used to hydrolyze bovine α-lactalbumin at 25 and 70 °C under non-reducing conditions. The breakdown products were identified by mass spectrometry. At 25 °C, the low proportion of α-lactalbumin in an unfolded state in equilibrium with the native state underwent limited hydrolysis leading to the production of peptides, that were no longer degraded (final peptides). At 70 °C, the protein was in a molten globule-like state according to circular dichroism and complete cleavage of the protein was achieved. At 70 °C, the protein was first quickly cleaved, then unfolded, leading to the release of intermediate peptides, from which final peptides were eventually produced. The amino-terminal 1–58 and carboxy-terminal 95–123 regions were readily cleaved, whereas the central region including the calcium-binding domain was more resistant. Some peptides were produced at 70 °C, but not at 25 °C. The choice of accurate experimental conditions may be of importance for the preparation of functional peptides.
Invariant Thr244 is essential for the efficient acylation step of the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Streptococcus mutans
Biochemical Journal, 400 (3), pp. 521-530.
Pailot, A., D'Ambrosio, K., Corbier, C., Talfournier, F., Branlant, G.
Gen. Comp. Endocrinol. 147, 17-23.
Prunet P., Sturm A., Milla S.
Assessment of dietary zinc requirement of weaned piglets fed diets with or without microbial phytase
Journal of Animal Physiology and Animal Nutrition, 90 (1-2), pp. 50-59.
Revy, P.S., Jondreville, C., Dourmad, J.Y., Nys, Y.
Cahiers de Nutrition et de Dietetique, 41 (3), pp. 139-146.
Rychen, G., Ducoulombier-Crepineau, C., Jurjanz, S., Mejean, L., Feidt, C.
The thermal stability of Aspergillus oryzae alpha-amylase in presence of sugars and polyols
Journal of Food Process Engineering, 29 (3), pp. 287-303.
Samborska, K., Guiavarc'h, Y., Van Loey, A., Hendrickx, M.
The aim of this study was to test whether it is possible to estimate the heat stability of Aspergillus oryzae alpha-amylase (a-amylase) based on the amount of hydroxyl (OH) groups provided in a buffer solution. The thermal stability of the enzyme in a presence of different sugars (sucrose and trehalose) and polyols (mannitol, sorbitol, lactitol and glycerol) was investigated in the temperature range of 62-68C on a kinetic basis. It was investigated if the protective effect of additional substances was correlated to the number of hydroxyl groups (nOH) provided by each of them (per volume unit of the enzyme solution nOH). All additives showed a protective effect on the enzyme\'s heat stability, which was strongly dependent on the added compound concentration. Among all stabilizing compounds investigated, sucrose exhibited the largest protective effect. The decimal reduction time of a-amylase activity increased by 33.9 times when 420 mg/mL of sucrose was added to the environment. When the same concentration of trehalose was used, the D-value increased by 6.4 times compared to the value in the buffer system. The nOH provided in the enzyme solution could not be related to the D-values for the enzyme thermal inactivation, meaning that the enzyme heat stability was not dependent on the nOH.
Ethological comparison of the effects of a bovine alpha-s1-casein tryptic hydrolysate and diazepam on the behaviour of rats in two models of anxiety
Pharmacology Biochemistry and Behavior, 84 (3), pp. 517-523.
Violle, N., Messaoudi, M., Lefranc-Millot, C., Desor, D., Nejdi, A., Demagny, B., Schroeder, H.
A bovine alpha-S1-casein tryptic hydrolysate was previously demonstrated to display an anxiolytic-like activity in the conditioned defensive burying and in the elevated plus-maze models when i.p. injected. The present study assessed the anxiolytic-like effects of this tryptic hydrolysate after an oral administration in rats faced to the same behavioural situations using diazepam as a reference. In a first experiment, the behavioural effects of the hydrolysate in the conditioned defensive burying test were investigated at doses ranging 5-50 mg/kg. The results showed that the minimal dose required to elicit an anxiolytic-like activity is 15 mg/kg. In a second experiment, the alpha-S1-casein tryptic hydrolysate (15 mg/kg, p.o.) was demonstrated to display an anxiolytic-like activity similar to diazepam (3 mg/kg, p.o.) in the conditioned defensive burying test and the elevated plus-maze. However, the ethological analysis of behaviour indicated that this hydrolysate has a different activity compared to diazepam. While diazepam induced a disinhibition state in rats, possibly related to the risk-taking behaviour observed after a benzodiazepine ingestion in humans, the tryptic hydrolysate did not display such a side effect. These results suggest that the mechanism of action of the bovine alpha-s1-casein tryptic hydrolysate may differ from that of diazepam.
Determinism of the induction of the reproductive cycle in female Eurasian perch, Perca fluviatilis: Identification of environmental cues and permissive factors
Aquaculture, 261 (2), pp. 706-714.
Wang, N., Gardeur, J.-N., Henrotte, E., Marie, M., Kestemont, P., Fontaine, P.
Short time scale changes in underwater irradiance in a wind-exposed lagoon (Vaccarès lagoon, France): Efficiency of infrequent field measurements of water turbidity or weather data to predict irradiance in the water column.
Hydrobiologia, 551 (1), pp. 3-16.
Banas, D., Grillas, P., Auby, I., Lescuyer, F., Coulet, E., Moreteau, J.-C., Millet, B.
High frequency water sampling in the wind-exposed Vaccarès lagoon revealed frequent and rapid changes in suspended solid (SS) concentrations in the water column. SS concentrations, sometimes higher than 800 mg l -1, were significantly correlated with antecedent wind conditions. Mean wind velocity during the 5-33 h before water sampling or maximal wind velocity during the previous 8.5-22 h were good predictors of SS concentrations in the water column. Underwater irradiance at canopy level was modeled (r 2= 0.66, n = 7584) using the SS calculated from the relationship between SS and antecedent mean wind velocity and the surface irradiance data measured at the weather station close to the study site. On the other hand, we have shown that in this wind-exposed lagoon, mean underwater irradiance can not be effectively estimated using infrequent measurements of the optical properties of water.
Sigma factor WhiG and its regulation constitute a target of a mutational phenomenon occurring during aerial mycelium growth in Streptomyces ambofaciens ATCC23877
Research in Microbiology, 156 (3), pp. 328-340.
Catakli, S., Andrieux, A., Decaris, B., Dary, A.
Intestinal metabolism of PAH: In vitro demonstration and study of its impact on PAH transfer through the intestinal epithelium
Environmental Research, 98 (1), pp. 22-32.
Cavret, S., Feidt, C.
Food would seem to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). In vivo studies suggest a transfer in intestinal epithelium by diffusion, which appears extensively governed by the physicochemical properties of PAHs, particularly lipophilicity. However, other mechanisms, such as metabolism, are considered to intervene. Our work aimed at testing in vitro intestinal metabolism and defining its impact on transepithelial transport of PAHs. Caco-2 cells were cultivated on permeable filters and incubated with 14C-labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phe), which differ in their physicochemical properties. The results showed that the cells were able to metabolize the compounds. In basal media, Phe appeared to be the least hydroxylated molecule (45% after a 6-h exposure), followed by Pyr (65%) and finally BaP (96%). Inhibition of PAH metabolism showed a determinant effect on kinetics profiles. Transfer in the basal compartment of BaP, Pyr, and Phe radioactivities was, respectively, 26, 4, and 2 times lower with inhibitors, corroborating that intestinal metabolism of PAHs would have a positive impact on their transfer, an impact that increased with their lipophilicity. Furthermore, after a 6-h incubation, metabolites were also detected in apical medium. These findings suggested that intestinal metabolism might play a key role in intestinal barrier permeability and thus in the bioavailability of tested micropollutants.
Differential transfer of organic micropollutants through intestinal barrier using Caco-2 cell line
Journal of Agricultural and Food Chemistry, 53 (7), pp. 2773-2777.
Cavret, S., Feidt, C., Laurent, F.
Food seems to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs) and dioxins. In vivo studies showed a blood absorption of these xenobiotics after their ingestion. Our work aimed at studying the in vitro transfer of PAHs and dioxins through intestinal barrier. Caco-2 cells were cultivated on permeable filters to measure transepithelial permeability of 14C labeled 2,3,7,8- tetrachlorodibenzo-p-dioxin, benzo[a]pyrene, pyrene, and phenanthrene, which differed in their physicochemical properties. The results showed that the molecules were able to cross intestinal cell layers. All the molecules were detected associated with cells, even if the dioxin was the less uptaken compound. Phenanthrene appeared in basal media faster, and its level after a 6-h exposure was respectively 1.1, 2, and 7 times higher than pyrene, benzo[a]pyrene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin levels. These findings suggest that intestinal epithelium plays a key role in selective permeability and then in bioavailibility of micropollutants.
Short communication: Study of mammary epithelial role in polycyclic aromatic hydrocarbons transfer to milk
Journal of Dairy Science, 88 (1), pp. 67-70.
Cavret, S., Feidt, C., Le Roux, Y., Laurent, F.
Food would appear to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). Many studies have shown the presence of PAHs in milk and dairy products, suggesting that they can represent a part of this contamination. Our work aimed at defining in vitro the mammary barrier role in PAH transfer to milk. Mac T cells were cultivated on permeable filters to measure transepithelial permeability of 14C labelled benzo[a]pyrene, pyrene and phenanthrene which differed in their physicochemical properties. The results showed that only two molecules, phenanthrene and pyrene, were able to cross mammary cell layers. Phenanthrene radioactivity appeared more quickly in apical media and its level after a six-hour exposure was 1.3 times higher than for pyrene and 7.7 times higher than for benzo[a]pyrene. These findings suggested that mammary epithelium could play a key role in the selective transfer of PAHs from food to milk.
Phospholipid transfer protein (PLTP) deficiency reduces brain vitamin E content and increases anxiety in mice
FASEB Journal, 19 (2), pp. 296-297.
Desrumaux, C., Risold, P.-Y., Schroeder, H., Deckert, V., Masson, D., Athias, A., Laplanche, H., Le Guern, N., Blache, D., Jiang, X.-C., Tall, A.R., Desor, D., Lagrost, L.
Vitamin E supplementation constitutes a promising strategy in the prevention of neurodegenerative diseases. Here, we show that a phospholipid transfer protein (PLTP) is widely expressed in the brain where it appears to function as a transfer factor for α-tocopherol, the main isomer of vitamin E. PLTP deficiency results in significant depletion of brain α-tocopherol in both homozygous (–30.1%, P<0.0002) and heterozygous (–18.0%, P<0.05) PLTP knocked-out mice. α-tocopherol depletion in PLTP-deficient homozygotes is associated with the elevation of lipofuscin (+25% and +450% increases in cortex and substantia nigra, respectively), cholesterol oxides (+54.5%, P<0.05), and cellular peroxides (+32.3%, P<0.01) in the brain. Complete PLTP deficiency in homozygotes is accompanied by increased anxiety as shown by fewer entries (8.3% vs. 44.4% in controls, P<0.01) and less time spent (1.7% vs. 41.3% in controls, P<0.05) in the open arms of an elevated plus-maze, in the absence of locomotor deterioration. Thus, the vitamin E transfer activity of PLTP appears to be a key process in preventing oxidative damage in the brain, and PLTP-deficient mice could be a new model of the contribution of oxidative brain injury in the etiology of neurodegenerative diseases.
A 5-month period of epilepsy impairs spatial memory, decreases anxiety, but spares object recognition in the lithium-pilocarpine model in adult rats
Epilepsia, 46 (4), pp. 499-508.
Detour, J., Schroeder, H., Desor, D., Nehlig, A.
Purpose: In temporal lobe epilepsy (TLE), interictal behavioral disorders affect patient\'s quality of life. Therefore we studied long-term behavioral impairments in the lithium-pilocarpine (li-pilo) model of TLE. Methods: Eleven li-pilo adult rats exhibiting spontaneous recurrent seizures (SRSs) during 5 months were compared with 11 li-saline rats. Spatial working memory was tested in a radial arm maze (RAM), anxiety in an elevated plus-maze (EPM), and nonspatial working memory in an object-recognition paradigm. Neuronal loss was assessed on thionine brain sections after behavioral testing. Results: In the RAM, the time to complete each session and the number of errors per session decreased over a 5-day period in li-saline rats but remained constant and significantly higher in li-pilo rats. In the EPM, the number of entries in and time spent on open arms were significantly higher in li-pilo than li-saline rats. In the object-recognition task, the two groups exhibited a comparable novelty preference for the new object. Neuronal loss reached 47-90% in hilus, CA1, amygdala, and piriform and entorhinal cortex. Conclusions: In li-pilo rats having experienced SRS for 5 months, performance in the object-recognition task is spared, which suggests that object discrimination remains relatively intact despite extensive damage. Neuronal loss in regions mediating memory and anxiety, such as hippocampus, entorhinal cortex, and amygdala, may relate to impaired spatial orientation and decreased anxiety.
Crystal structure and solution NMR dynamics of a D (Type II) peroxiredoxin glutaredoxin and thioredoxin dependent: A new insight into the peroxiredoxin oligomerism
Biochemistry, 44 (6), pp. 1755-1767.
Echalier, A., Trivelli, X., Corbier, C., Rouhier, N., Walker, O., Tsan, P., Jacquot, J.-P., Aubry, A., Krimm, I., Lancelin, J.-M.
Determination of phenanthrene and hydroxyphenanthrenes in various biological matrices at trace levels using gas chromatography-mass spectrometry
Journal of Analytical Toxicology, 29 (3), pp. 175-181.
Grova, N., Monteau, F., Le Bizec, B., Feidt, C., Andre, F., Rychen, G.
A fast and efficient multiresidue extraction-purification procedure was developed for low levels (ppb range) of phenanthrene and hydroxyphenanthrene in biological matrices, in order to quantify phenanthrene and metabolites in blood, milk, urine, and biological tissues of lactating goats. Detection and identification of the analytes (phenanthrene and 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene) were achieved using gas chromatography coupled to mass spectrometry. Deuterium-labeled phenanthrene was used as internal standard for phenanthrene and 2-OHfluorene for metabolites. The developed method includes enzymatic hydrolysis, liquid-liquid extraction, and Envi-Chrom P SPE column purification. Analyses were performed in the selected ion monitoring mode to achieve ad hoc sensitivity in accordance with analyte concentrations in food samples. Detection limits were between 2.3 and 5.1 ng/mL (ppb) for milk samples, 0.5 and 2.5 ng/mL for urine and blood samples, and 1.9 and 8.0 ng/g for tissue samples. This original multiresidue and multimatrix analytical methodology was applied to metabolism studies and polycyclic aromatic hydrocarbon (PAH) risk assessment. We demonstrated, for the first time, that metabolites were present in milk. These results suggested that usual PAHs analysis methods based on the detection of native molecule are not representative of the real contamination of biological matrices.
Purification, characterization, thermal and high-pressure inactivation of a pectin methylesterase from white grapefruit (Citrus paradisi)
Innovative Food Science and Emerging Technologies, 6 (4), pp. 363-371.
Guiavarc'h, Y., Segovia, O., Hendrickx, M., Van Loey, A.
White grapefruit pectin methylesterase (PME) was successfully purified by affinity chromatography using a kiwi PME inhibitor as ligand. Electrophoretic analysis combined with isothermal and isobaric-isothermal inactivation treatments suggested the presence of a labile PME fraction and a stable PME fraction with molecular weights of 31.5 kDa and 23.7 kDa, respectively. Both isothermal and isobaric-isothermal PME inactivation could be described by fractional conversion models with about 20% of the initial activity corresponding to the stable fraction. Optimum pH-ionic strength conditions for grapefruit PME thermostability were determined. Purified heat-labile PME (in 20 mM Tris Buffer (pH 7.0)) was submitted to combined thermal and high-pressure inactivation experiments in the ranges 10-62 °C and 0.1-800 MPa. The combined pressure-temperature dependence of the inactivation rate constants could be accurately described by a third degree polynomial model, showing a clear antagonistic effect of pressure and temperature on PME inactivation at temperatur =58 °C in a pressure range of 0.1-300 MPa. In the context of fruit-juice processing, the results obtained suggest that a combined high-pressure-(low/mild) heat treatment can eliminate up to 80% of the total PME activity therefore significantly limiting the cloud-loss defect in juices.
Combined use of two single-component enzymatic time-temperature integrators: Application to industrial continuous rotary processing of canned ravioli
Journal of Food Protection, 68 (2), pp. 375-383.
Guiavarc'h, Y., Zuber, F., Van Loey, A., Hendrickx, M.
Two original, highly dehydrated, small single-component enzymatic time-temperature integrator (TTI) systems, TTIL and TTIS, were prepared. Their z-values were 13.9 and 16.4°C, respectively, and they were based on Bacillus licheniformis a-amylase and Bacillus subtilis a-amylase, respectively. The isothermal calibration of these two TTIs revealed that (i) they can be used in the temperature range of 100 to 140°C, (ii) results can be read within 5 min, and (iii) they can be used individually for the measurements of process values 13.9°CF 121.1°C and 16.4°CF121.1°C up to 98 min and 85 min, respectively. Because these two TTIs have different z-values above 10°C, they could be used in combination with the multicomponent TTI concept to estimate process values 10°CF121.1°C inside particles of a solid or liquid food submitted to rotary processing. Raviolis in tomato sauce sterilized in an industrial-scale reel and spiral continuous retort were examined in this study. Two methods, based on the combination of a one-dimensional explicit finite difference heat-transfer model with the experimental responses of the TTIs, were used to take into account the possible deviations in evaluation of 10°CF121.1°C values. A process value 10°CF121.1°C of 23.6 min with a standard deviation of 1.5 min was determined inside raviolis using the multicomponent TTI approach, and a process value 10°CF 121.1°C of 33.6 min with a standard deviation of 1.5 min inside the sauce was calculated from the temperature recording data.
Extended study on the influence of z-value(s) of single and multicomponent time-temperature integrators on the accuracy of quantitative thermal process assessment
Journal of Food Protection, 68 (2), pp. 384-395.
Guiavarc'h, Y.P., Van Loey, A.M., Hendrickx, M.E.
The possibilities and limitations of single- and multicomponent time-temperature integrators (TTIs) for evaluating the impact of thermal processes on a target food attribute with a ztarget value different from the ZTTI value(s) of the TTI is far from sufficiently documented. In this study, several thousand time-temperature profiles were generated by heat transfer simulations based on a wide range of product and process thermal parameters and considering a ztarget value of 10°C reference temperature of 121.1°C, both currently used to assess the safety of food sterilization processes. These simulations included 15 different ztarget=10°CF121.1°1C values in the range 3 to 60 min. The integration of the time-temperature profiles with ZTTI values of 5.5 to 20.5°C in steps of 1°C allowed generation of a large database containing for each combination of product and process parameters the correction factor to apply to the process value FmultiTTI, which was derived from a single- or multicomponent TTI, to obtain the target process value 10°CF]2\\.i-c• The table and the graph results clearly demonstrated that multicomponent TTIs with z-values close to 10°C can be used as an extremely efficient approach when a single-component TTI with a z-value of 10°C is not available. In particular, a two-component TTI with z1 and z2 values respectively above and below the Z target value (10°C in this study) would be the best option for the development of a TTI to assess the safety of sterilized foods. Whatever process and product parameters are used, such a TTI allows proper evaluation of the process value 10°CF121.C.
E. coli proteolytic activity in milk and casein breakdown
Reproduction Nutrition Development, 45 (4), pp. 485-496.
Haddadi, K., Moussaoui, F., Hebia, I., Laurent, F., Le Roux, Y.
Previous studies have focused on both LPS and E. coli experimental mastitis and underlined the respective roles of endogenous proteolysis (including plasmin from the blood stream and other proteases from milk leukocytes), as well as the presence of E. coli in a more intricate system. The aim of this study was to assess the role of E. coli in milk proteolysis and especially that of its proteases in casein breakdown. The first part consisted in the incubation of 104 cfu·mL-1 of the E. coli strain in raw milk at 37 °C for 24 h; the same milk was also incubated with 0.04% sodium azide. Several parameters were evaluated: CFU, plasmin activity, gelatinase activity and pH 4.6 insoluble peptides, including the proportion of ![\"$\\gamma$\"](\"http://rnd.edpsciences.org/articles/rnd/abs/2005/04/r5403/img1.gif\")
-CN. The profile of gelatinase activity was determined by zymography and identified by immunoblotting. In the second part of the study, we examined the profile of CN (![\"$\\alpha$\"](\"http://rnd.edpsciences.org/articles/rnd/abs/2005/04/r5403/img2.gif\")
s-, ![\"$\\beta$\"](\"http://rnd.edpsciences.org/articles/rnd/abs/2005/04/r5403/img3.gif\")
- and ![\"$\\kappa$\"](\"http://rnd.edpsciences.org/articles/rnd/abs/2005/04/r5403/img4.gif\")
-CN) breakdown by E. coli lysate. The results suggest that E. coli proteases have a direct effect on CN, and the increase of -CN in inoculated milk may be generated by both plasmin and the gelatinase. Moreover, the gelatinase activity in the inoculated milk was higher after 24 h of incubation.
Milchwissenschaft, 60 (2), pp. 134-137.
Humbert, G., Chang, O., Gaillard, J.-L.
Phosphorus in pig nutrition [Le phosphore dans la nutrition des porcs]
Productions Animales, 18 (3), pp. 183-192.
Jondreville, C., Dourmad, J.-Y.
Replacement of zinc sulphate by microbial phytase for piglets given a maize-soya-bean meal diet
Animal Science, 81 (1), pp. 77-83.
Jondreville, C., Hayler, R., Feuerstein, D.
Animal Research, 54 (1), pp. 3-15.
Jurjanz, S., Monteils, V.
Tissue distribution and bioconcentration factors of PCDD/Fs in the liver and adipose tissue following chronic ingestion of contaminated milk in rats
Chemosphere, 60 (7), pp. 929-938.
Laurent, C., Marchand, P., Feidt, C., Le Bizec, B., Rychen, G.
Appearance and technological characteristics in wild and reared Eurasian perch, Perca fluviatilis (L.)
Aquaculture, 246 (1-4), pp. 295-311.
Mairesse, G., Thomas, M., Gardeur, J.-N., Brun-Bellut, J.
Emptying of extensive fishponds: Practices, control and environmental incidences.
Bulletin d'Association de Geographes Francais, 82 (2), pp. 224-233.
Masson, G., Banas, D., Francois, D., Cizel, O., Leglize, L., Didier, S., Corbonnois, J.
Effects of a tryptic hydrolysate from bovine milk alpha S1- casein on hemodynamic responses in healthy human volunteers facing successive mental and physical stress situations.
European Journal of Nutrition 44 (2), pp. 128-132.
Messaoudi, M., Lefranc-Millot, C., Desor, D., Demagny, B., Bourdon, L.
Behavioural and cognitive effects of oligofructose-enriched inulin in rats.
British Journal of Nutrition 93, pp. S27-S30.
Messaoudi, M., Rozan, P., Nejdi, A., Hidalgo, S., Desor, D.
Journal of Applied Microbiology, 99 (3), pp. 641-648.
Nicodeme, M., Grill, J.-P., Humbert, G., Gaillard, J.-L.
Journal of Microbiological Methods, 62 (1), pp. 71-81.
Roussel, Y., Wilks, M., Harris, A., Mein, C., Tabaqchali, S.
Productions Animales, 18 (5), pp. 355-366.
Rychen, G., Ducoulombier-CREPINEAU, C., Grova, N., Jurjanz, S., Feidt, C.
The influence of moisture content on the thermostability of Aspergillus oryzae a-amylase
Enzyme and Microbial Technology, 37 (2), pp. 167-174.
Samborska, K., Guiavarc'h, Y., Van Loey, A., Hendrickx, M.
The thermal stability of Aspergillus oryzae a-amylase in systems of different moisture content was investigated. To obtain systems of reduced moisture content the enzyme was freeze-dried with addition of maltodextrin and equilibrated above saturated salt solutions. Other systems applied were aqueous solutions of maltodextrin. The thermal inactivation kinetics could be accurately described by a first-order model in all systems studied except the system at moisture content 0.029 g H2O/g dry basis, which showed a biphasic inactivation pattern. Reduced moisture content had a significant effect on a-amylase thermostability, the enzyme being far more thermostable in maltodextrin systems at reduced moisture content than in aqueous solutions. When the moisture content decreased from 3.5 g H2O/g dry basis to 0.029 g H2O/g dry basis, the temperature range of inactivation increased from 70-75°C to 100-115°C. The activation energy (z-value) of thermal inactivation was also affected by the moisture content in the system.
Antibacterial activity of lactophoricin, a synthetic 23-residues peptide derived from the sequence of bovine milk component-3 of proteose peptone
Journal of Dairy Science, 87 (6), pp. 1621-1626.
Campagna, S., Mathot, A.-G., Fleury, Y., Girardet, J.-M., Gaillard, J.-L.
In vitro intestinal transfer and metabolism of polycyclic aromatic hydrocarbons
Polycyclic Aromatic Compounds, 24 (4-5), pp. 513-525.
Cavret, S., Rychen, G., Feidt, C.
PAH contamination of the grass Lolium perenne exposed to vehicular traffic
Agronomie, 24 (8), pp. 503-506.
Crepineau-Ducoulombier, C., Dan-Badjo, A.T., Rychen, G.
Domestication des Poissons
Avant-propos. Numéro spécial Productions Animales, 17, 3.
FONTAINE P.
L'élevage de la perche commune, une voie de diversification pour l'aquaculture continentale
Productions Animales, 17 (3), pp. 189-193.
FONTAINE P.
Domestication et croissance chez les poissons
Productions Animales, 17 (3), pp. 217-225.
Fontaine P., Le Bail P.Y.
Multiple forms of equine alpha-lactalbumin: Evidence for N-glycosylated and deamidated forms
International Dairy Journal, 14 (3), pp. 207-217.
Girardet, J.-M., N'negue, M.-A., Egito, A.S., Campagna, S., Lagrange, A., Gaillard, J.-L.
Development characterization and use of a high-performance enzymatic time-temperature integrator for the control of sterilization process' impacts
Biotechnology and Bioengineering, 88 (1), pp. 15-25.
Guiavarc'h, Y., Van Loey, A., Zuber, F., Hendrickx, M.
A small sized single-component enzymatic time temperature integrator (TTI) was developed. It consisted of glass beads coated with Bacillus licheniformis a-amylase (BLA) and stabilizing additives in a dehydrated form. Post heating residual enzymatic activity was used as a response property of the TTI. Under isothermal conditions, different batches of the system were characterized by zTTI-values around 13.5°C in the temperature range 100-130°C as well as by their ability to provide a response within 5 min after thermal processing. When used under non-isothermal conditions in a model food (silicone spheres), the system allowed to measure process-values zTTIF121.1°C to 60 min with an average error of 10.9%. The capabilities of the system were validated in a real solid/liquid food matrix sterilized by retorting. The combination of FTTI-values with heat transfer simulations based on finite difference calculations allowed for the determination of process values, which evaluated actual process-values 10°CF121.1°C up to 90 min with an average error of 11.4%. The good performances of the system as well as its easiness of preparation and use, make the latter a valuable biological device for thermal process assessment.
Bacillus licheniformis a-amylase immobilized on glass beads and equilibrated at low moisture content: Potentials as a Time-Temperature Integrator for sterilisation processes
Innovative Food Science and Emerging Technologies, 5 (3), pp. 317-325.
Guiavarc'h, Y., Van Loey, A., Zuber, F., Hendrickx, M.
Time-Temperature Integrator (TTI) systems based on Bacillus licheniformis a-amylase (BLA), sucrose and salts immobilized at the surface of non-porous glass beads (inert filler) and under several low moisture conditions (aw in the range 0-0.63 after equilibrium at 4 °C) were studied. These systems showed interesting thermal stabilities in the range 100-132 °C under isothermal conditions. More precisely, the TTI system equilibrated at a w=0.48 (BLAGB48) showed capabilities, under non-isothermal conditions, for monitoring the process value zTTI=9.4°CF121.1°C in the range 0-30 min with an absolute average % error of 14%. Although this error is comparable to already reported systems, this TTI showed numerous advantages over the latter: (i) The time required for the moisture equilibration of the systems was significantly reduced (2-3 days instead of 3 weeks). (ii) The aggregation of the a-amylase during heating could be overcome enhancing the solubilization of the a-amylase after heat treatment in only 1 min. (iii) Consequently, it became possible to use convenient residual activity reading method (only 5 min required) instead of a residual heat denaturation enthalpy reading (15 min required) as a response property of the system. (iv) The amount of a-amylase required per TTI was 50-fold smaller. (v) Finally, larger thermal impacts (process values up to 30 min) could be monitored.
Lipids, 39 (1), pp. 19-24.
Jurjanz, S., Monteils, V., Juaneda, P., Laurent, F.
Endogenous proteolysis in quarter milk fraction after LPS infusion
Milchwissenschaft, 59 (1-2), pp. 6-10.
Le Roux, Y., Lutz, S., Laurent, F., Moussaoui, F.
Endogenous proteolysis in quarter milk fraction was studied after the infusion of 10 μg of lipopolysaccharide of E. coli, 64 h post-infusion, during a single milking. Several parameters were considered and compared to theuninfused heterolateral quarter: somatic cell count (SCC), proteose peptone content and plasmin activity. Qualitative change of proteose peptone fraction and somatic cell proteolytic activity were investigated. In milk of control quarter no increase of SCC was noticed, plasmin activity was the main origin of proteose peptone content. A very wide increase of SCC was measured in infused quarter between the 3 fractions of milk. In the same time, proteose peptone content increased and a specific peptide appeared in milk of infused quarter. Despite of the increase of SCC during milking of infused quarter, no qualitative change of cellular proteolytic activity was measured.
Reared perch v. wild perch - first results about organoleptical and technological quality.
Journal of Fish Biology. 2004, 65 : 321.
Mairesse, G. ; Thomas, M. ; Gardeur, J.N. ; Brun-Bellut, J.
Effects of geographic origin on growth and food intake in Eurasian perch (Perca fluviatilis L.) juveniles under intensive culture conditions.
Aquaculture, 229, pp. 117-128.
Mandiki R., Blanchard G., M?lard C., Koskela J., Darek D., Fontaine P. Kestemont P.
Effects of geographic origin on growth and food intake in Eurasian perch (Perca fluviatilis L.) juveniles under intensive culture conditions.
Aquaculture, 229, pp. 117-128.
Mandiki R., Blanchard G., Mélard C., Koskela J., Darek D., Fontaine P. Kestemont P.
Are sex steroids involved in the sexual growth dimorphism in Eurasian perch juveniles?
Physiology and Behavior, 80 (5), pp. 603-609.
Mandiki, S.N.M., Houbart, M., Babiak, I., Vandeloise, E., Gardeur, J.N., Kestemont, P.
Screening and construction of probiotic strains with enhanced protective properties against intestinal disorders
Microbial Ecology in Health and Disease, 16 (2-3), pp. 86-95.
Mercenier, A., Hols, P., Roussel, Y., Perez-Martinez, G., Buesa, J., Wilks, M., Pozzi, G., Remaut, E., Morelli, L., Grangette, C., Monedero, V., Palumbo, E., Foligne, B., Steidler, L., Nutten, S.
The endogenous androgen-regulated sialorphin modulates male rat sexual behaviour.
Hormones and Behavior 46 (5), pp. 684-691.
Messaoudi, M., Desor, D., Nejdi, A., Rougeot, C.
Influence of photoperiod on the onset of gonadogenesis in Eurasian perch Perca fluviatilis
Aquaculture, 241 (1-4), pp. 561-574.
Migaud, H., Fontaine, P., Kestemont, P., Wang, N., Brun-Bellut, J.
Off-season spawning of Eurasian perch Perca fluviatilis
Aquaculture International, 12 (1), pp. 87-102.
Migaud, H., Gardeur, J.-N., Kestemont, P., Fontaine, P.
Proteolysis in milk during experimental Escherichia coli mastitis
Journal of Dairy Science, 87 (9), pp. 2923-2931.
Moussaoui, F., Vangroenweghe, F., Haddadi, K., Le Roux, Y., Laurent, F., Duchateau, L., Burvenich, C.
This work consisted of the intramammary infections (IMI) of 8 heifers by high doses of Escherichia coli to study both the proteolytic activity in milk and the resulting peptides. Therefore, a milking kinetic has been followed, and several parameters have been studied, such as proteose peptones (PP) fraction (quantitative and qualitative changes), plasmin activity (PA), milk somatic cell count (SCC), and bacterial count. A qualitative study of milk proteins and PP was performed by sodium dodecyl sulfate-PAGE, and the peptides recovered in PP during the acute phase of inflammation were amino-terminal micro-sequenced. A BSA increase in milk over time supported the hypothesis of an increase in the permeability of the epithelial barrier. A significant increase in PP content, considered to be an indicator of proteolysis, was observed from postinfusion hours (PIH) 12 to 48. Both the E. coli bacterial count and the SCC increased from PIH 3 to 216. Plasmin activity was increased noticeably from PIH 15 to 24. The respective increases in SCC, bacterial count, and PA suggest their involvement in a global mechanism responsible for the increase in proteolysis in milk after E. coli challenge. Somatic cell count and E. coli may be involved from PIH 3 to 216, and PA involvement might be highlighted during the maximum proteolysis, from PIH 15 to 24. A qualitative study of PP fraction by electrophoresis revealed the apparition of 5 peptide bands: P1 and P2 previously recovered during the lipopolysaccharide challenge, and E1 (27.0 kDa), E2 (15.5 kDa), and E3 (9.0 kDa) were specific to E. coli challenge; E1, E2, and E3 contained casein fragments. The roles played by leukocytes and E. coli are discussed.
Isolation and characterization of copolymers of beta-lactoglobulin, alpha-lactalbumin, beta-casein, and alphas1-casein generated by pressurization and thermal treatment of raw milk
Journal of Dairy Science, 87 (11), pp. 3614-3622.
Nabhan, M.A., Girardet, J.-M., Campagna, S., Gaillard, J.-L., Le Roux, Y.
Raw skim milk was submitted to high pressure (300 to 600 MPa) and temperature (4 to 70°C) treatments for 2 or 5 min. The combined effects of pressure and temperature on milk proteins induced structural changes and polymer and copolymer formation characterized by anion-exchange and size-exclusion fast protein liquid chromatography and electrophoretic techniques. Approximately half of the ß-lactoglobulin formed polymers, and the other half formed large copolymers, mainly with ![\"{kappa}\"](\"http://jds.fass.org/math/kappa.gif\")
-casein, ![\"{alpha}\"](\"http://jds.fass.org/math/agr.gif\")
-lactalbumin via intermolecular disulfide bond exchange, and s1-casein via physicochemical interactions, in proportions of 1.0:0.7:0.3:0.1, respectively. Minor whey proteins (serum albumin, immunoglobulins, and lactoferrin) also participated in the formation of the copolymers but to a lesser extent. Two populations of the copolymers were found with apparent molecular masses ranging from 440 to 2000 kDa for the first and more than 2000 kDa for the second. On the contrary, for heated milks the aggregation kinetics obtained by combination of high pressure and thermal treatment were very fast, as no intermediates such as dimers and small size oligomers were observed after pressurization, whatever the temperature studied. Lactosylation of proteins as well as proteolysis were very limited. A ß-casein amino-terminal peptide of 22 kDa was specifically recovered in milk samples treated under the more drastic conditions (500 MPa/55°C per 5 min and 600 MPa/70°C per 5 min) and might have been generated by neutral proteases such as elastase released from somatic cells present in milk. No casein was released from the micelle whatever the combination of high pressure and temperature studied.
Effect of zinc supplemented as either an organic or an inorganic source and of microbial phytase on zinc and other minerals utilisation by weanling pigs
Animal Feed Science and Technology, 116 (1-2), pp. 93-112.
Revy, P.S., Jondreville, C., Dourmad, J.Y., Nys, Y.
New antitumour cyclic astin analogues: Synthesis, conformation and bioactivity
Journal of Peptide Science, 10 (2), pp. 92-102.
Rossi, F., Zanotti, G., Saviano, M., Iacovino, R., Palladino, P., Saviano, G., Amodeo, P., Tancredi, T., Laccetti, P., Corbier, C., Benedetti, E.
Active site mutagenesis and phospholipid hydroperoxide reductase activity of poplar type II peroxiredoxin
Physiologia Plantarum, 120 (1), pp. 57-62.
Rouhier, N., Gelhaye, E., Corbier, C., Jacquot, J.P.
Influence of environment structure and food availability on the foraging behaviour of the laboratory rat.
Behavioural Processes 60 (3), pp. 191-198.
Arcis, V., Desor, D.
New plate sediment traps for lentic systems.
Archiv fur Hydrobiologie, 158 (2), pp. 283-288.
Banas, D., Masson, G.
A new type of sediment trap, which overcomes a methodological gap in the study of sedimentation fluxes in shallow lentic systems, is described. The sedimentation rates measured in the field with these new traps were compared with those from other plate and cylindrical traps. As do other plate traps, the new traps allow the resuspension of deposited particles observed on bottom sediments. Furthermore, the new traps do not disturb particle sedimentation on the collecting area and allow to collect the net sedimentation rates in lentic systems.
The delivery rate of dietary carbohydrates affects cognitive performance in both rats and humans.
Psychopharmacology 166 (1), pp. 86-90.
Benton, D., Ruffin, M.P., Lassel, T., Nabb, S., Messaoudi, M., Vinoy, S., Desor, D., Lang, V.
Effect of low continuous 99Tc intake on its absorption and metabolism in young rats
Journal of Environmental Radioactivity, 67 (3), pp. 169-180.
Berthol, D., Feidt, C., Brun Bellut, J.
Spontaneous chromosome circularization and amplification of a new amplifiable unit of DNA belonging to the terminal inverted repeats in Streptomyces ambofaciens ATCC 23877
Archives of Microbiology, 179 (6), pp. 387-393.
Catakli, S., Andrieux, A., Leblond, P., Decaris, B., Dary, A.
Intestinal absorption of 14C from 14C-phenanthrene, 14C-benzo[a]pyrene and 14C-tetrachlorodibenzo-para-dioxin: Approaches with the Caco-2 cell line and with portal absorption measurements in growing pigs
Reproduction Nutrition Development, 43 (2), pp. 145-154.
Cavret, S., Laurent, C., Feidt, C., Laurent, F., Rychen, G.
Contamination of pastures by polycyclic aromatic hydrocarbons (PAHs) in the vicinity of a highway
Journal of Agricultural and Food Chemistry, 51 (16), pp. 4841-4845.
Crepineau, C., Rychen, G., Feidt, C., Le Roux, Y., Lichtfouse, E., Laurent, F.
To assess PAH contamination pastures, grass and soil samples have been collected from 10 m (d1), 50 m (d2), and 150 m (d3) perpendicular to a French highway (70 000 vehicles per day) and at a control site in a rural area away from nearby contaminating sources. Total PAH concentration ranges from 767 ng/g dry weight to 3989 ng/g dry weight, according to the matrix and the distance from the highway. Distance is not a significant factor for PAH deposition on grass, while in soil it has an effect between d1 and d2 or d3. The total PAH concentration in highway samples is 8 times higher than in control site samples for grass and 7 to 4 times higher for soil. Fluoranthene, pyrene, and phenanthrene are the major PAHs in grass samples at the control site and the highway, but the concentrations are about 5 times higher near the highway. In soil samples collected near the highway, the values of concentrations between all compounds are not statistically different. PAH deposition on grass is linked to the physicochemical properties of the compounds, which lead to a specific distribution of each molecule (according to their volatility and the number of aromatic rings) while no specific behavior is revealed in soil.
Assessment of soil and grass Polycyclic Aromatic Hydrocarbon (PAH) contamination levels in agricultural fields located near a motorway and an airport
Agronomie, 23 (4), pp. 345-348.
Crepineau-Ducoulombier, C., Rychen, G.
Crystal structure of two ternary complexes of phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Bacillus stearothermophilus with NAD and D-glyceraldehyde 3-phosphate
Journal of Biological Chemistry, 278 (15), pp. 12968-12976.
Didierjean, C., Corbier, C., Fatih, M., Favier, F., Boschi-Muller, S., Branlant, G., Aubry, A.
Crystallization and preliminary X-ray studies of the glutaredoxin from poplar in complex with glutathione
Acta Crystallographica - Section D Biological Crystallography, 59 (6), pp. 1043-1045.
D'Ambrosio, K., Kauffmann, B., Rouhier, N., Benedetti, E., Jacquot, J.-P., Aubry, A., Corbier, C.
International Dairy Journal, 13 (10), pp. 813-820.
Egito, A.S., Girardet, J.-M., Poirson, C., Molle, D., Humbert, G., Miclo, L., Gaillard, J.-L.
Effect of cadmium on gonadogenesis and metamorphosis in Pleurodeles waltl (urodele amphibian)
Aquatic Toxicology, 64 (2), pp. 143-153.
Flament, S., Kuntz, S., Chesnel, A., Grillier-Vuissoz, I., Tankozic, C., Penrad-Mobayed, M., Auque, G., Shirali, P., Schroeder, H., Chardard, D.
In the amphibian Pleurodeles waltl, steroid hormones play a key role in sex differentiation. Since cadmium has been reported to block receptors of sex steroid hormones, we analyzed the effects of this heavy metal on Pleurodeles larvae gonadogenesis. At stage 42, larvae die in the presence of 10.9 µM Cd in the rearing tap water, with TL50 of 46.3 h, but the concentration of 5.5 µM is tolerated for more than 60 days. When used at 5.5 µM cadmium accumulation measured by atomic absorption spectrophotometry (AAS) in total homogenates of larvae at stage 54 (after 77 days of exposure to the heavy metal) reached 58.1 µg/g of dry weight. At stage 54, we did not detect inhibitory effects on gonadogenesis in larvae reared in the presence of 5.5 µM Cd since stage 42. When the exposure to 5.5 µM Cd was lengthened after stage 54, metamorphosis was delayed and could not be completed. When larvae were exposed to 10.9 µM Cd from stage 54, metamorphosis did not occur and gonad development was stopped. Our study demonstrates a lack of a direct effect of cadmium on sex determination-differentiation but a strong inhibitory effect on metamorphosis, which impairs further gonadal development.
Involvement of sex steroids in final stages of oogenesis in Eurasian perch, Perca fluviatilis
Fish Physiology and Biochemistry, 28 (1-4), pp. 331-332.
Fontaine, P., Migaud, H., Mandiki, R., Gardeur, J.N., Kestemont, P., Fostier, A.
Ca-Methyl, Ca-n-Propylglycine Homo-oligomers
Macromolecules, 36 (21), pp. 8164-8170.
Formaggio, F., Crisma, M., Toniolo, C., Broxterman, Q.B., Kaptein, B., Corbier, C., Saviano, M., Palladino, P., Benedetti, E.
Identification and characterization of a third thioredoxin h in poplar
Plant Physiology and Biochemistry, 41 (6-7), pp. 629-635.
Gelhaye, E., Rouhier, N., Vlamis-Gardikas, A., Girardet, J.-M., Sautiere, P.-E., Sayzet, M., Martin, F., Jacquot, J.-P.
Histopathological alterations and functional brain deficits after transient hypoxia in the newborn rat pup: A long term follow-up
Neurobiology of Disease, 14 (2), pp. 265-278.
Grojean, S., Schroeder, H., Pourie, G., Charriaut-Marlangue, C., Koziel, V., Desor, D., Vert, P., Daval, J.-L.
To assess temporal brain deficits consecutive to severe birth hypoxia, newborn rats were exposed for 20 min to 100% N2. This treatment induced a long-term growth retardation and a delayed, but only transient, neuronal loss (~25%) in the CA1 hippocampus and parietal cortex, starting from 3 days and peaking at 6 days post-hypoxia. The expression profiles of various apoptosis-regulating proteins (including Bcl-2, Bax, p53 and caspase-3) were well correlated to the alterations of nuclear morphology depicted by 4,6-diamidino-2-phenylindole (DAPI). Whereas they confirmed a gradual histological recovery, specific DNA fragmentation patterns suggested that birth hypoxia may transiently reactivate the developmental programme of neuronal elimination. Although they successfully achieved various behavioral tests such as the righting reflex, negative geotaxis, locomotor coordination, and the eight-arm maze tasks, both developing and adult hypoxic rats were repeatedly slower than controls, suggesting that birth hypoxia is associated to moderate but persistent impairments of functional capacities.
Influence of sugars and polyols on the thermal stability of purified tomato and cucumber pectinmethylesterases: A basis for TTI development
Enzyme and Microbial Technology, 33 (5), pp. 544-555.
Guiavarc'h, Y., Sila, D., Duvetter, T., Van Loey, A., Hendrickx, M.
Tomato and cucumber pectinmethylesterases (PME) were extracted and purified by affinity chromatography using kiwi PME inhibitor (PMEI) as a ligand. The optimal pH ionic strength combination, which led to a maximal thermostability of purified cucumber PME was identified as 6.7 and 1.25M NaCl, respectively. The effect of sugars such as sucrose and trehalose and the effect of polyols including mannitol, sorbitol, lactitol and glycerol on the thermostability of purified PME was evaluated based on the residual enzymic activity after isothermal treatments performed in temperatures between 55 and 77°C. Under all conditions, purified tomato PME showed a first order inactivation curve, while purified cucumber PME showed a biphasic inactivation curve. Purified tomato PME showed a maximal thermostability in citrate buffer, pH 4.5 complemented with glycerol 50% (v/v) (D77°C-value of 6.62min and z-value of 5.34°C). The heat stable fraction of purified cucumber PME exhibited a maximal thermostability in Bis-Tris buffer, pH 6.7, 1.25M NaCl complemented with glycerol 60% (v/v) (D75°C-value of 2.79min and z-value of 5.23°C). The potential of both PME to be used as time-temperature integrators (TTIs) to monitor pasteurization process is discussed. Finally, when calculating the equivalent number of hydroxyl groups (nOH) provided by each stabilizer per volume unit of enzyme solution, it could be observed that the D-value for purified tomato PME was exponentially related to the nOH. This observation may be used as a predictive tool for enzyme stabilization. The influence of the OH source on the thermal stability was also investigated in terms of nature of the OH source (nature of the molecule and level of polymerization of a polyvinyl alcohol, PVA).
Détermination et validation d’un intégrateur chimique temps-température utilisable dans les produits appertisés.
Bulletin du Centre Technique de la Conservation des Produits Agricoles, 46, pp. 4-10.
Guiavarc’h, Y., Bordese, D.
Dietary means to better control the environmental impact of copper and zinc by pigs from weaning to slaughter
Livestock Production Science, 84 (2), pp. 147-156.
Jondreville, C., Revy, P.S., Dourmad, J.Y.
Veterinary Research, 34 (5), pp. 629-645.
Le Roux, Y., Laurent, F., Moussaoui, F.
Influence of protein/energy ratio on carcass quality during the growing period of Eurasian perch (Perca fluviatilis)
Aquaculture, 217 (1-4), pp. 453-464.
Mathis, N., Feidt, C., Brun-Bellut, J.
Synthesis of sex steroids in final oocyte maturation and induced ovulation in female Eurasian perch, Perca fluviatilis
Aquatic Living Resources, 16 (4), pp. 380-388.
Migaud, H., Mandiki, R., Gardeur, J.-N., Fostier, A., Kestemont, P., Fontaine, P.
Influence of photoperiod regimes on the Eurasian perch gonadogenesis and spawning
Fish Physiology and Biochemistry, 28 (1-4), pp. 395-397.
Migaud, H., Mandiki, R., Gardeur, J.N., Kestemont, P., Bromage, N., Fontaine, P.
Journal of Dairy Science, 86 (4), pp. 1163-1170.
Moussaoui, F., Laurent, F., Girardet, J.M., Humbert, G., Gaillard, J.-L., Le Roux, Y.
Lait, 83 (2), pp. 101-110.
Moussaoui, F., Le Roux, Y., Laurent, F.
Zinc in pig nutrition: The essential trace element and potential adverse effect on environment [Le zinc dans l'alimentation du porc: Oligoelement essentiel et risque potentiel pour l'environnement]
Productions Animales, 16 (1), pp. 3-18.
Revy, P.S., Jondreville, C., Dourmad, J.Y., Nys, Y.
Proceedings of the National Academy of Sciences of the United States of America 100 (14), pp. 8549-8554.
Rougeot, C., Messaoudi, M., Hermitte, V., Gaëlle Rigault, A., Blisnick, T., Dugave, C., Desor, D., Rougeon, F.
Assessing the digestibility of proteins using the porto-arterial difference method in pigs [Mesure de la digestibilite des proteines par la methode des differences porto-arterielles chez l'espece porcine]
OCL - Oleagineux Corps Gras Lipides, 10 (1), pp. 25-30.
Rychen, G.
International Dairy Journal, 13 (1), pp. 15-27.
Tauzin, J., Miclo, L., Roth, S., Molle, D., Gaillard, J.-L.
a-aminoxy acids as building blocks for the oxime and hydroxylamine pseudopeptide links. Application to the synthesis of human elastase inhibitors
Journal of Peptide Science, 9 (5), pp. 282-299.
Vanderesse, R., Thevenet, L., Marraud, M., Boggetto, N., Reboud, M., Corbier, C.
Mortality and non-specific immune response of Eurasian perch, Perca fluviatilis, during the spawning season
Fish Physiology and Biochemistry, 28 (1-4), pp. 523-524.
Wang, N., Migaud, H., Acerete, L., Gardeur, J.N., Tort, L., Fontaine, P.
Nouvelles trappes à sédiment destinées aux milieux peu profonds vidangeables.
Revue des Sciences de l'Eau, 15 (1), pp. 263-272.
Banas, D., Capizzi, S., Masson, G., Leglize, L., Wagner, P., Pihan, J.C.
Sediment traps are a unique tool that can be used to investigate particle settling flux throughout the water column, whereas other methods such as sediment dating can only measure accumulation rates of bottom sediments. Several works on trapping efficiency have shown that cylindrical traps with height/diameter ratio greater than to 5 (10 in turbulent systems) are the more appropriate instruments to correctly measure the downward settling flux of particulate matter. Furthermore, traps with a diameter narrower than 5 cm should be avoided. It is well documented that bottle-type vessels overestimate the settling sediment whereas funnels and flat containers underestimate it. All this support the idea that an ideal trap must be at least 25 cm high, and in this sense, numerous studies investigating shallow aquatic systems have neglected a large proportion of the water column. Consequently, mechanical and biological processes occuring in this layer of the water column have not been taken into account. We have overcome this problem with a structure composed of two parts The first part is a receptacle (bucket) buried in the sediment and intended to receive cylindrical traps. The top of the receptable is placed 2 cm above the sediment. A guide made of a rope covered with a PVC tube is placed in the centre of the receptacle. This receptacle is intended to receive cylindrical traps whose tops stand less than 5 cm higher than the surface of the sediments. The second part is composed of seven cylinders (height/diameter ratio = 10) which are fixed in a PVC disc 600 mm in diameter and 15 mm deep. The cylinders are placed around the central axis of the PVC disc. The bottom of the cylinders is closed with a removable polyethylene cap. Another cylinder, through which the guide can slide, is placed on the central axis. The bottom part of this last cylinder is ballasted with concrete. The stability of this second part, during both deposition and removal steps, is ensured by the low density of the PVC disc, the ballast at the bottom of the central cylinder, and the symmetry of the structure. This removable part may be lifted from the receptacle with three 2 mm diameter ropes attached to the PVC disc and fixed to a float. This apparatus may be used as deep as five meters. The sediment traps were tested in two extensively-managed fish ponds in North-Eastern France. Our investigations showed that tubes with a diameter between 26 and 140 mm could be efficiently used to estimate the sedimentation rate, whereas cylinders with a narrower diameter missed a large amount of particles. The use of tubes with a diameter above 50 mm, which is preferable for the study of turbulent systems, seems to allow the collection of sufficient sediment during a short period of time. We selected tubes with a diameter of 57 mm, which made it possible to handle them easily during the removal. Our investigations showed that in turbulent systems and for high sedimentation rates (> 5 kg.m-2.month-1), the top of the cylinders must be placed 1 cm above the top of the PVC disc. When considering low sedimentation rates (< 5 kg.m-2.month-1), we did not observe any significant differences between the cylinders placed 0 and 1 cm above the PVC disc. Complementary investigations were conducted in order to compare sedimentation rates estimated 1) by the apparatus we designed, in which the top of the cylinders was placed 5 cm above the sediment surface, 2) by traditional traps (57 mm in diameter and a height/diameter ratio of 5) in which the top of the cylinders was 28.5 cm above the sediment surface. These results showed that in shallow systems (1.2 m deep), traditional traps underestimate the downward settling flux of particulate matter by 35 to 79%. Furthermore, we compared the organic matter content of the sediment collected by the two types of traps with the organic matter content of bottom sediment, suspended particles, and submerged macrophytes. Results showed that the underestimation of particles was not only due to the resuspension of bottom sediment, but also to the sedimentation of phytoplankton and submerged macrophyte fragments which are not collected by the traditional traps.
Discharge of sediments, nitrogen (N) and phosphorus (P) during the emptying of extensive fishponds: Effect of rain-fall and management practices
(2002) Hydrobiologia, 472, pp. 29-38.
Banas, D., Masson, G., Leglize, L., Pihan, J.C.
In 1997 and 1998 we assessed the input and output of suspended matter, nitrogen and phosphorus during the exploitation period of a fishpond in the Domaîne Départemental de Lindre (Moselle, north-eastern France). Special attention was given to the emptying period which was studied under different meteorological conditions (rainy and dry periods). The pond has a surface area of 2 ha, a volume of 16 000 m3 and is used for the production of various Cyprinidae (roach, bream, chub, pike, perch, carp). During the emptying operation, 630 and 2830 kg ha-1 of suspended matter, 10.8 and 36.5 kg ha-1 of Total-nitrogen and 1.2 and 5.1 kg ha-1 of Total-phosphorus were discharged from the pond during drought and heavy rainfall (50.5 mm in 166 h), respectively. Except for the emptying period, the pond retained 6850, 117 and 6.6 kg ha-1 of suspended matter, nitrogen and phosphorus, respectively. In the course of the emptying period, more than 32% of the suspended matter was discharged as was 8.5% of the nitrogen and 25% of the phosphate. For the whole exploitation period 4020 - 6220 kg ha-1 of suspended matter, 80-106 kg ha-1 of nitrogen and 1.6-5.5 kg ha-1 of phosphorus accumulated in the pond.
Temporal variations of sedimentation in shallow freshwater systems
Archiv fur Hydrobiologie, 153 (4), pp. 623-634.
Banas, D., Masson, G., Leglize, L., Pihan, J.C.
Nineteen new traps which made it possible to sample almost the whole water column in shallow systems were exposed on a monthly basis during 18 months in two ponds. Quantitative and qualitative temporal variation of settled particles was shown even though seasonal variation was generally masked by bottom sediment resuspension in these shallow aquatic systems. Sedimentation rates fluctuated on a seasonal basis. They were minimum in spring and maximum in summer. These fluctuations were linked to the high primary production observed. These new traps showed that decaying submersed macrophytes can be an important source of organic matter, as well as decay of blue-green algal blooms which have always been considered responsible for anoxic problems in fish ponds. Interference by the fish farmer at various times of the year also caused sudden high sedimentation rates (>200 g m-2 d-1). Sedimentation in the fish ponds was controlled by natural mechanisms partly similar to those that occur in lakes, and by mechanisms specific to shallow systems and to aquatic systems managed by man.
Lait, 82 (5), pp. 555-566.
Blel, M., Guingamp, M.-F., Gaillard, J.-L., Humbert, G.
Crystallization and preliminary X-ray data of a bifunctional peroxiredoxin from poplar
Acta Crystallographica Section D: Biological Crystallography, 58 (9), pp. 1501-1503.
Echalier, A., Corbier, C., Rouhier, N., Jacquot, J.-P., Aubry, A.
Separation and characterization of mares' milk alphaS1-, beta-, kappa-caseins, gamma-casein-like, and proteose peptone component 5-like peptides
Journal of Dairy Science, 85 (4), pp. 697-706.
Egito, A.S., Miclo, L., Lopez, C., Adam, A., Girardet, J.-M., Gaillard, J.-L.
Detection of polycyclic aromatic hydrocarbon levels in milk collected near potential contamination sources
Journal of Agricultural and Food Chemistry, 50 (16), pp. 4640-4642.
Grova, N., Feidt, C., Crepineau, C., Laurent, C., Lafargue, P.E., Hachimi, A., Rychen, G.
[14C] Milk, urine and faeces excretion kinetics in lactating goats after an oral administration of [14C]polycyclic aromatic hydrocarbons
International Dairy Journal, 12 (12), pp. 1025-1031.
Grova, N., Feidt, C., Laurent, C., Rychen, G.
Development of an enzymic time temperature integrator for sterilization processes based on Bacillus licheniformis a-amylase at reduced water content
Journal of Food Science, 67 (1), pp. 285-291.
Guiavarc'h, Y.P., Deli, V., Van Loey, A.M., Hendrickx, M.E.
The thermal stability of Bacillus licheniformis a-amylase at low moisture content was studied, based on isothermal experiments performed in a temperature range 113 to 125 °C. The thermal inactivation was monitored by measuring the decrease in thermal denaturation enthalpy and/or the decrease in enzymic activity on p-nitrophenyl-a-D-maltoheptaoside, or on starch as a substrate. Based on enthalpy readings, an enzymic system with a z-value of 10.4 °C was observed when using a relative humidity of 81% at 4 °C. A theoretical study showed that this system could be used as a Time Temperature Integrator (TTI) to monitor the safety of sterilization processes of numerous food products.
Validation and use of an enzymic time-temperature integrator to monitor thermal impacts inside a solid/liquid model food
Biotechnology Progress, 18 (5), pp. 1087-1094.
Guiavarc'h, Y.P., Dintwa, E., Van Loey, A.M., Zuber, F.T., Hendrickx, M.E.
Heat denaturation kinetics of Bacillus licheniformis a-amylase, equilibrated at 81% equilibrium relative humidity at 4°C (BLA81), was studied with help of isothermal and nonisothermal conditions by monitoring the decrease in enthalpy associated with the heat denaturation of the enzyme. Due to its low water content, BLA81 denaturation could be studied in the range of 118-124°C. Two batches of BLA81 were successfully validated under nonisothermal conditions allowing the determinations of process values (reference temperature of 121.1°C) in the range of 1-15 min. In a second step, BLA81 was used as a time-temperature integrator (TTI) to investigate potential differences of process values received by freely moving spherical particles as compared to a centrally fixed particle (single-position impact) inside cans containing water as brine. Results showed that the process value received by freely moving particles can be from 5.6% (4 rpm) to 19.7% (8 rpm) smaller than the process value received by the centrally fixed sphere. This means that evaluating the process value by means of a particle fixed at the critical point in a package can lead to potentially overestimations of the actual process value with possible hazardous quality/safety implications. These results highlight the potentials of the TTI technology to monitor the safety of heat-processed agitated solid/liquid foodstuffs.
Développement d’un intégrateur temps température enzymatique pour le contrôle des procédés de stérilisation.
Bulletin du Centre Technique de la Conservation des Produits Agricoles, 42, pp. 2-11.
Guiavarc’h, Y., Van Loey, A., Hendrickx. M.
Thioredoxins and related proteins in photosynthetic organisms: Molecular basis for thiol dependent regulation
Biochemical Pharmacology, 64 (5-6), pp. 1065-1069.
Jacquot, J.-P., Gelhaye, E., Rouhier, N., Corbier, C., Didierjean, C., Aubry, A.
Copper in pig nutrition: Essential trace element, growth promoter, and its potential adverse effects on human nutrition and environment [Le cuivre dans l'alimentation du porc: Oligoelement essentiel, facteur de croissance et risque potentiel pour l'Homme et l'environnement]
Productions Animales, 15 (4), pp. 247-265.
Jondreville, C., Revy, P.S., Jaffrezic, A., Dourmad, J.Y.
Portal absorption of 14C after ingestion of spiked milk with 14C-phenanthrene, 14C-benzo[a]pyrene or 14C-TCDD in growing pigs
Chemosphere, 48 (8), pp. 843-848.
Laurent, C., Feidt, C., Grova, N., Mpassi, D., Lichtfouse, E., Laurent, F., Rychen, G.
Induction of out-of-season spawning in Eurasian perch Perca Fluviatilis : effects of rates of cooling and cooling duration on female gametogenesis and spawning
Aquaculture, 205, pp. 253-267
Migaud, H., Fontaine, P., Sulistyo, I., Kestemont, P., Gardeur, J.N.
Journal of animal science, 80 (1), pp. 235-241.
Monteils, V., Jurjanz, S., Colin-Schoellen, Blanchart, G., Laurent, F.
Mechanisms involved in milk endogenous proteolysis induced by a lipopolysaccharide experimental mastitis
Journal of Dairy Science, 85 (10), pp. 2562-2570.
Moussaoui, F., Michelutti, I., Le Roux, Y., Laurent, F.
Enzymatic activities of bovine peripheral blood leukocytes and milk polymorphonuclear neutrophils during intramammary inflammation caused by lipopolysaccharide
Clinical and Diagnostic Laboratory Immunology, 9 (4), pp. 812-817.
Prin-Mathieu, C., Le Roux, Y., Faure, G.C., Laurent, F., Bene, M.C., Moussaoui, F.
Bioavailability of two sources of zinc in weanling pigs
Animal Research, 51 (4), pp. 315-326.
Revy, P.-S., Jondreville, C., Dourmad, J.-Y., Guinotte, F., Nys, Y.
Thirty-two pigs, weaned at 28 days of age with an average body weight of 9 kg, were used in an experiment devoted to the assessment of the bioavailability of an organic Zn source (ZnOrg) compared to Zn sulfate. Pigs were fed a basal diet containing 28 mg\'kg-11 of Zn supplemented with ZnS04 or ZnOrg to provide 0,10,20 and 30 mg\'kg-1 of supplemental Zn. In order to reduce the amount and the variability of their Zn stores, pigs were fed the basal diet for a 7-day adjustment period preceding a 19-day experimental period. Growth performance and bone bending moment were not affected by the level nor the source of zinc. On the contrary, plasma zinc concentration and alkaline phosphatase activity (P < 0.001), bone zinc concentration (P < 0. 001), liver and empty body zinc concentrations (P < 0.01) as well as the amount of Zn retained estimated both by the balance technique (BT) (P < 0.001) and by the comparative slaughter technique (CST) (P < 0.01) increased linearly in response to supplemental Zn. However, the two Zn sources exhibited a similar bioavailability. Twenty-seven percent of Zn intake was retained when measured by means of the balance technique, regardless of the dietary level or zinc source. Zn retention was 54% lower when measured by means of the CST as compared to the BT.
Milk-arterial plasma transfer of PCDDs and PCDFs in pigs
Journal of Agricultural and Food Chemistry, 50 (6), pp. 1695-1699.
Rychen, G., Laurent, C., Feidt, C., Grova, N., Lafargue, P.E., Hachimi, A., Laurent, F.
Journal of Dairy Research, 69 (1), pp. 95-101.
Rychen, G., Mpassi, D., Jurjanz, S., Mertes, M., Lenoir-Wijnkoop, I., Antoine, J.M., Laurent, F.
45Ca as a marker to assess portal absorption of calcium from milk in the growing pig
Lait, 82 (3), pp. 337-342.
Rychen, G., Mpassi, D., Laurent, F.
Elevated rate of collagen solubilization and postmortem degradation in muscles of lambs with high growth rates: Possible relationship with activity of matrix metalloproteinases
Journal of Animal Science, 80 (7), pp. 1871-1878.
Sylvestre, M.N., Balcerzak, D., Feidt, C., Baracos, V.E., Brun Bellut, J.
FEBS Letters, 531 (2), pp. 369-374.
Tauzin, J., Miclo, L., Gaillard, J.-L.
Verhandlungen Internationale Vereinigung für Theoretische und Angewandte Limnologie, 27(7), pp. 3982-3985.
Banas, D., Masson, G., Leglize, L.
Biological Activities and Structural Properties of the Atypical Bacteriocins Mesenterocin 52B and Leucocin B-TA33a
Applied and Environmental Microbiology, 67 (4), pp. 1418-1422.
Corbier, C., Krier, F., Mulliert, G., Vitoux, B., Revol-Junelles, A.-M.
Lait, 81 (6), pp. 715-729.
Denis, T., Humbert, G., Gaillard, J.-L.
Lait, 81 (6), pp. 775-785.
Egito, A.S., Girardet, J.-M., Miclo, L., Gaillard, J.-L.
Susceptibility of Equine alpha- and beta-caseins to hydrolysis by chymosin
International Dairy Journal, 11 (11-12), pp. 885-893.
Egito, A.S., Girardet, J.-M., Miclo, L., Molle, D., Humbert, G., Gaillard, J.-L.
Typology of individual growth in sea bass (Dicentrarchus labrax)
Aquatic Living Resources, 14 (4), pp. 223-231.
Gardeur, J.-N., Lemarie, G., Coves, D., Boujard, T.
Biostatistical implications of individual variability in growth in rainbow trout and Atlantic salmon
Aquaculture, 195 (1-2), pp. 51-59.
Gardeur, J.N., Paspatis, M., Gelineau, A., Boujard, T.
Dilational rheology of mixed ß-casein/Tween 20 and ß-casein (f114-169)/Tween 20 films at oil-water interface
Journal of Colloid and Interface Science, 243 (2), pp. 515-522.
Girardet, J.-M., Humbert, G., Creusot, N., Chardot, V., Campagna, S., Courthaudon, J.-L., Gaillard, J.-L.
Ileal digestibility of amino acids and estimates of endogenous amino acid losses in pigs fed wheat, triticale, rye, barley, maize and sorghum
Animal Research, 50 (2), pp. 119-134.
Jondreville, C., Van den Broecke, J., Ga^tel, F., Grosjean, F., Van Cauwenberghe, S., Se?ve, B.
Milk-blood transfer of 14C-tagged polycyclic aromatic hydrocarbons (PAHs) in pigs
Journal of Agricultural and Food Chemistry, 49 (5), pp. 2493-2496.
Laurent, C., Feidt, C., Lichtfouse, E., Grova, N., Laurent, F., Rychen, G.
Vaccine, 19 (28-29), pp. 3927-3935.
Lee, M.H., Roussel, Y., Wilks, M., Tabaqchali, S.
Crystal structure of the wild-type and D30A mutant thioredoxin h of Chlamydomonas reinhardtii and implications for the catalytic mechanism
Biochemical Journal, 359 (1), pp. 65-75.
Menchise, V., Corbier, C., Didierjean, C., Saviano, M., Benedetti, E., Jacquot, J.-P., Aubry, A.
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 15 (10), pp. 1780-1782.
Miclo, L., Perrin, E., Driou, A., Papadopoulos, V., Boujrad, N., Vanderesse, R., Boudier, J.F., Desor, D., Linden, G., Gaillard, J.L.
Portal absorptional of 15N and amino nitrogen in the growing pig after ingestion of labelled milk, yogurt or heat-treated yogurt
Reproduction Nutrition Development, 41 (2), pp. 153-162.
Mpassi, D., Rychen, G., Feidt, C., Mertes, M., Laurent, F., Lenoir-Wijnkoop, I., Antoine, J.-M.
International Journal of Developmental Neuroscience. 19(4), 365-72
Nebigil C.G., Etienne N., Schaerlinger B., Hickel P., Launay J.M., Maroteaux L.
Journal of Dairy Research, 68 (3), pp. 437-449.
Saint-Denis, T., Humbert, G., Gaillard, J.-L.
Post-mortem evolution of non-protein nitrogen and its peptide composition in growing lamb muscles
Meat Science, 58 (4), pp. 363-369.
Sylvestre, M.N., Feidt, C., Brun-Bellut, J.
Characterization of a novel integrative element, ICESt1, in the lactic acid bacterium Streptococcus thermophilus
Applied and Environmental Microbiology, 66 (4), pp. 1749-1753.
Burrus, V., Roussel, Y., Decaris, B., Guédon, G.
Livestock Production Science, 67 (1-2), pp. 41-53.
Colin-Schoellen, O., Jurjanz, S., Laurent, F.
Piv-Pro[psi][CH2-NH-O]Gly-NHiPr
Acta Crystallographica Section C: Crystal Structure Communications, 56 (8), pp. 995-996.
Corbier, C., Didierjean, C., Thevenet, L., Vanderesse, R., Marraud, M.
DNA rearrangements at the extremities of the Streptomyces ambofaciens linear chromosome: Evidence for developmental control
Biochimie, 82 (1), pp. 29-34.
Dary, A., Martin, P., Wenner, T., Decaris, B., Leblond, P.
Le transfert des micropolluants organiques dans la chaine alimentaire etat et perspectives de recherche
OCL - Oleagineux Corps gras Lipides, 7 (5), pp. 431-435.
Feidt, C., Grova, N., Laurent, C., Rychen, G., Laurent, F.
Journal of Dairy Science, 83 (11), pp. 2410-2421.
Girardet, J.-M., Debomy, L., Courthaudon, J.-L., Miclo, L., Humbert, G., Gaillard, J.-L.
Camel (Camelus dromedarius) milk PP3: Evidence for an insertion in the amino-terminal sequence of the camel milk whey protein
Biochemistry and Cell Biology, 78 (1), pp. 19-26.
Girardet, J.-M., Saulnier, F., Gaillard, J.-L., Ramet, J.-P., Humbert, G.
Ileal digestibility of protein and amino acids of feed peas with different trypsin inhibitor activity in pigs
Canadian Journal of Animal Science, 80 (4), pp. 643-652.
Grosjean, F., Jondreville, C., Williatte-Hazouard, I., Skiba, F., Carrouee, B., Gatel, F.
Gas chromatography-mass spectrometry study of polycyclic aromatic hydrocarbons in grass and milk from urban and rural farms
European Journal of Mass Spectrometry, 6 (5), pp. 457-460.
Grova, N., Laurent, C., Feidt, C., Rychen, G., Laurent, F., Lichtfouse, E.
Les intégrateurs enzymatiques temps-température pour le suivi des process de stérilisation : contexte et théorie.
Bulletin du Centre Technique de la Conservation des Produits Agricoles, 32, pp. 12-20.
Guiavarc'h, Y., Van Loey, A., Hendrickx. M.
Les intégrateurs enzymatiques temps-temperature pour le suivi des process de stérilisation : les dispositifs existants.
Bulletin du Centre Technique de la Conservation des Produits Agricoles, 33, pp. 2-11.
Guiavarc’h, Y., Van Loey, A., Hendrickx. M.
Ileal amino acid digestibility and estimates of endogenous amino acid losses in pigs fed rapeseed meal, sunflower meal and soybean meal
Canadian Journal of Animal Science, 80 (3), pp. 495-506.
Jondreville, C., Van Den Broecke, J., Gatel, F., Grosjean, F., Van Cauwenberghe, S., S?ve, B.
Ileal true digestibility of amino acids in wheat milling by-products for pigs
Animal Research, 49 (1), pp. 55-65.
Jondreville, C., Van Den Broecke, J., Grosjean, F., Van Cauwenberghe, S., Gatel, F.
Ileal digestibility of amino acids in maize gluten feed for pigs
Journal of Animal and Feed Sciences, 9 (1), pp. 99-111.
Jondreville, C., Van Den Broecke, J., Grosjean, F., Van Cauwenberghe, S., Ga^tel, F.
Influence of daylength on growth, heterogeneity, gonad development, sexual steroid and thyroid levels, and N and P budgets in Perca fluviatilis
Aquaculture, 186 (3-4), pp. 253-265.
Jourdan, S., Fontaine, P., Boujard, T., Vandeloise, E., Gardeur, J.N., Anthouard, M., Kestemont, P.
Free radical production and changes in superoxide dismutases associated with hypoxia/reoxygenation-induced apoptosis of embryonic rat forebrain neurons in culture
Free Radical Biology and Medicine, 29 (12), pp. 1291-1301.
Lievre, V., Becuwe, P., Bianchi, A., Koziel, V., Franck, P., Schroeder, H., Nabet, P., Dauca, M., Daval, J.-L.
Following hypoxia/reoxygenation (6h/96h), cultured neurons from the embryonic rat forebrain undergo delayed apoptosis. To evaluate the participation of oxidative stress and defense mechanisms, temporal evolution of intraneuronal free radical generation was monitored by flow cytometry using dihydrorhodamine 123, in parallel with the study of transcriptional, translational, and activity changes of the detoxifying enzymes Cu/Zn-SOD and Mn-SOD. Two distinct peaks of radical generation were depicted, at the time of reoxygenation (+ 27%) and 48 h later (+ 25%), respectively. Radical production was unaffected by caspase inhibitors YVAD-CHO or DEVD-CHO, which prevented neuronal damage, suggesting that caspase activation is not an upstream initiator of radicals in this model. Cell treatment by vitamin E (100 µM) displayed significant neuroprotection, whereas the superoxide generating system xanthine/xanthine oxidase induced apoptosis. Transcript and protein levels of both SODs were reduced 1 h after the onset of hypoxia, but activities were transiently stimulated. Reoxygenation was associated with an increased expression (139%), but a decreased activity (21%) of the inducible Mn-SOD, whereas Cu/Zn-SOD protein and activity were low and progressively increased until 48 h post-hypoxia, when the second rise in radicals occurred. In spite of a temporal regulation of SODs, which parallels radical formation, oxidative stress might account for neurotoxicity induced by hypoxia.
Identification and typing of Streptomyces strains: Evaluation of interspecific, intraspecific and intraclonal differences by RAPD fingerprinting
Research in Microbiology, 151 (10), pp. 853-864.
Martin, P., Dary, A., Andre, A., Decaris, B.
Crystal structure of a collagen-like polypeptide with repeating sequence Pro-Hyp-Gly at 1.4 A° resolution: Implications for collagen Hydration
Biopolymers, 56 (1), pp. 8-13.
Menchise, V., Corbier, C., Didierjean, C., Jacquot, J.P., Benedetti, E., Saviano, M., Aubry, A.
Electrophoresis, 21 (1), pp. 949-955.
Perrin, C., Gonzalez-Marquez, H., Gaillard, J.-L., Bracquart, P., Guimont, C.
High-performance liquid chromatographic analysis of muscular interstitial arginine and norepinephrine kinetics - A microdialysis study in rats
Journal of Chromatography B: Biomedical Sciences and Applications, 745 (2), pp. 279-286.
Siaghy, E.M., Devaux, Y., Schroeder, H., Sfaksi, N., Ungureanu-Longrois, D., Zannad, F., Villemot, J.P., Nabet, P., Mertes, P.M.
Complex interactions between the L-arginine/nitric oxide synthase (NOS) pathway and the sympathetic nervous system have been reported. Methods capable of measuring L-arginine and norepinephrine (NE) have mainly been reported for plasma. We report the use of the microdialysis technique combined with high-performance liquid chromatography (HPLC) for measurement of both L-arginine and NE within the same tissue microdialysis sample. The microdialysis probe consisted of linear flexible probes (membrane length: 10 mm, outside diameter: 290 µm, molecular weight cut-off 50 kDa). The method used for L-arginine measurement was HPLC with fluorescence detection, giving a within-run and a between-day coefficient of variation of 2.9 and 12.8%, respectively. The detection limit was 0.5 pM/20 µl injected for L-/D- arginine. The method used for NE measurement was HPLC with electrochemical detection. The coefficients of variation were 4% for within-assay precision and 7.5% for between-assay precision. The detection limit for NE was 1 fmol/20 µl injected. The microdialysis technique coupled with HPLC system was validated in vivo to measure muscular interstitial concentrations of both arginine and NE under baseline conditions and after intravenous infusion of 500 mg/kg of L-arginine or D-arginine. In conclusion, the microdialysis technique coupled to HPLC allows the simultaneous measurements of both L- arginine and NE within the same tissue microenvironment and will enable the study of the complex interactions between the L-arginine/NO pathway and sympathetic nervous system within the interstitial space of different organs.
Reproductive cycle and plasma levels of steroids in male Eurasian perch Perca fluviatilis
Aquatic Living Resources, 13 (2), pp. 99-106.
Sulistyo, I., Fontaine, P., Rinchard, J., Gardeur, J.-N., Migaud, H., Capdeville, B., Kestemont, P.
Transient hypoxia may lead to neuronal proliferation in the developing mammalian brain: From apoptosis to cell cycle completion
Neuroscience, 91 (1), pp. 221-231.
Bossenmeyer-Pourie, C., Chihab, R., Schroeder, H., Daval, J.L.
Cerebral hypoxia/ischemia was shown to induce delayed, apoptotic neuronal death occurring through biochemical pathways potentially sharing common events with cell proliferation. This study was designed to test the hypothesis that a sublethal hypoxia may promote mitotic activity in developing central neurons. After six days in vitro, cultured neurons from the forebrain of 14-day-old rat embryos were exposed to hypoxia (95% N2/5% CO2) for 3 h and re-oxygenated for up to 96 h. Controls were kept in normoxia. As a function of time, cell viability was measured by diphenyltetrazolium bromide, and rates of DNA and protein synthesis were monitored using [3H]thymidine and [3H]leucine, respectively. Morphological features of apoptosis, necrosis and mitosis were scored under fluorescence microscopy after nuclear staining with 4,6-diamidino-2-phenylindole, and the expression profile of proliferating cell nuclear antigen, a cofactor for DNA polymerase, was analysed by immunohistochemistry. Data were compared to those obtained after transient hypoxia for 6 h followed by re-oxygenation for 96 h and which was shown to induce apoptosis. Whereas a 6-h insult reduced cell viability, with 23% of the neurons exhibiting apoptosis by the end of re- oxygenation, a 3-h hypoxia led to a cycloheximide-sensitive increase in the final number of living neurons compared to controls (13%, P < 0.01), with no signs of apoptosis, significantly increased thymidine incorporation into acid-precipitable fraction, and persistent over-expression of proliferating cell nuclear antigen. Accordingly, final score of mitotic nuclei was significantly enhanced. In addition, the cell cycle inhibitor olomoucine (50 µM) prevented apoptosis consecutive to a 6-h hypoxia, but impaired the stimulatory effects of a 3-h insult. These findings support the conclusion that some neurons exposed to sublethal hypoxia may dodge apoptotic death by fully achieving the cell cycle.
Colloids and Surfaces B: Biointerfaces, 13 (6), pp. 299-309.
Campagna, S., Van Mau, N., Heitz, F., Humbert, G., Gaillard, J.-L.
Surface active and emulsifying properties of casein micelles compared to those of sodium caseinate
International Dairy Journal, 9 (3-6), pp. 411-412.
Courthaudon, J.-L., Girardet, J.-M., Campagne, S., Rouhier, L.-M., Campagna, S., Linden, G., Lorient, D.
Evolution of the linear chromosomal DNA in Streptomyces: Is genomic variability developmentally modulated?
Research in Microbiology, 150 (7), pp. 439-445.
Dary, A., Martin, P., Wenner, T., Leblond, P., Decaris, B.
Release of major ions during rigor mortis development in kid Longissimus dorsi muscle
Meat Science, 51 (1), pp. 81-90.
Feidt, C., Brun-Bellut, J.
Proteolysis of milk casein micelle and sodium caseinate in oil-in-water emulsions
International Dairy Journal, 9 (3-6), pp. 409-410.
Girardet, J.-M., Courthaudon, J.-L., Campagna, S., Puyjalon, V., Lorient, D., Linden, G.
Lait, 79 (4), pp. 457-463.
Guingamp, M.-F., Humbert, G., Midon, P., Nicolas, M., Linden, G.
Intraclonal polymorphism in the bacterium Streptomyces ambofaciens ATCC23877: Evidence for a high degree of heterogeneity of the wild type clones
Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 430 (1), pp. 75-85.
Martin, P., Dary, A., Andre, A., Fischer, G., Leblond, P., Decaris, B.
Sequential changes in milk protein composition after experimental Escherichia coli mastitis
Lait, 79 (5), pp. 534-549.
Michelutti, I., Le Roux, Y., Rainard, P., Poutrel, B., Laurent, F.
Amino-terminal sequencing of the ovine milk fat globule membrane protein butyrophilin
Lait, 79 (2), pp. 275-279.
Montagne, L., Girardet, J.-M., Humbert, G.
Current Microbiology, 39 (1), pp. 342-347.
Perrin, C., Guimont, C., Bracquart, P., Gaillard, J.-L.
15N enrichment of casein amino acids in the milk from goats given a single intravenous dose of L-[15N]leucine
Journal of Dairy Research, 66 (2), pp. 283-288.
Rubert-Aleman, J., Rychen, G., Casseron, F., Laurent, F., Martin, G.J.
Modulation of lipid metabolism and spiramycin biosynthesis in Streptomyces ambofaciens unstable mutants
Applied and Environmental Microbiology, 65 (6), pp. 2730-2737.
Schauner, C., Dary, A., Lebrihi, A., Leblond, P., Decaris, B., Germain, P.
Hypoxia/reoxygenation induces apoptosis through biphasic induction of protein synthesis in cultured rat brain neurons
Brain Research, 787 (1), pp. 107-116.
Bossenmeyer, C., Chihab, R., Muller, S., Schroeder, H., Daval, J.-L.
To investigate biochemical events accounting for the outcome of central neurons following hypoxia/reoxygenation, cultured neurons from fetal rat forebrain were exposed to hypoxia (95% N2/5% CO2) for 6 h, and then reoxygenated for up to 96 h. Time-dependent changes in macromolecular biosynthesis were analysed by incorporation of [3H]uridine and [3H]leucine and were coupled to cell viability and lactate dehydrogenase leakage. Morphological features of necrosis and apoptosis were scored following nuclear incorporation of the fluorescent dye 4,6-diamidino-2-phenylindole. Hypoxia led to a 36% reduction of cell viability at the end of the reoxygenation period, while 23% of the neurons exhibited apoptosis. A biphasic increase in the rates of protein synthesis was measured 1 h after the onset of hypoxia (77% above controls) and by 48-h postreoxygenation (72%). The presence of cycloheximide during hypoxia inhibited both peaks of synthesis and prevented the development of apoptosis. Protein electrophoresis outlined specific alterations in constitutive proteins, and immunohistochemistry revealed an overexpression of the pro-apoptotic gene products Bax and ICE. Therefore, hypoxia followed by reoxygenation would trigger sequential changes in synthesis of specific proteins, leading to delayed and mainly apoptotic neuronal death.
Conformational Studies of a Synthetic Peptide from the Putative Lipid-binding Domain of Bovine Milk Component PP3
Journal of Dairy Science, 81 (12), pp. 3139-3148.
Campagna, S., Vitoux, B., Humbert, G., Girardet, J.M., Linden, G., Haertle, T., Gaillard, J.L.
Structure of the O-glycopeptides isolated from bovine milk component PP3
Glycoconjugate Journal, 15 (4), pp. 371-378.
Coddeville, B., Girardet, J.-M., Plancke, Y., Campagna, S., Linden, G., Spik, G.
Liberation of peptides during meat storage and their interaction with proteinase activity
Meat Science, 49 (2), pp. 223-231.
Feidt, C., Brun-Bellut, J., Dransfield, E.
Rapid separation of bovine whey proteins by membrane convective liquid chromatography, perfusion chromatography, continuous bed chromatography, and capillary electrophoresis
Lait, 78 (4), pp. 391-400.
Girardet, J.-M., Saulnier, F., Linden, G., Humbert, G.
Feeding value of pea (Pisum sativum, L.) 2. Nutritional value in the pig
Animal Science, 67 (3), pp. 621-625.
Grosjean, F., Bastianelli, D., Bourdillon, A., Cerneau, P., Jondreville, C., Peyronnet, C.
Journal of Dairy Science, 81 (11), pp. 2924-2933.
Jurjanz, S., Colin-Schoellen, O., Gardeur, J.N., Laurent, F.
Generation of a genetic polymorphism in clonal populations of the bacterium Streptomyces ambofaciens: Characterization of different mutator states
Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 421 (1), pp. 73-82.
Martin, P., Dary, A., Decaris, B.
Incorporation of [14C] in milk proteins after a ruminal infusion of D-[U-14C]glucose in dairy goats
Small Ruminant Research, 27 (3), pp. 251-256.
Rychen, G., Rubert-Aleman, X., Lucas, F., Blanchart, G., Laurent, F.
Long-term effects of early diazepam exposure on social differentiation in adult male rats subjected to the diving-for-food situation
Behavioral Neuroscience, 112 (5), pp. 1209-1217.
Schroeder, H., Toniolo, A.M., Nehlig, A., Desor, D.
The present study was designed to investigate the consequences of a chronic diazepam (DZ) exposure (10 mg/kg/day) during the first 3 weeks of life on social behavior of adult male rats measured in a situation of restricted access to food, the diving-for-food model. The treatment had no long-term effects on the acquisition of social roles related to feeding. However, DZ-exposed rats were less efficient than controls in carrying food from the feeder to the cage during the 1st session but were able to adapt and improve their performances during the 2nd one. In the home cage, DZ-exposed rats were more aggressive toward conspecifics than controls and compensated for their deficit of food by stealing it from the others. These results suggest that an early DZ exposure has long-term consequences on social behavior of rats, possibly reflecting a reduction of the level of emotionality.
Reproductive cycle and plasma levels of sex steroids in female Eurasian perch Perca fluviatilis
Aquatic Living Resources. 11, pp. 101-110.
Sulistyo, I., Rinchard, J., Fontaine, P., Gardeur, J.-N., Capdeville, B., Kestemont, P.
A new warning biomonitor using a weakly electric fish, Apteronotus albifrons (Gymnotiformes) and the effect of temperature on the bioelectric responses.
Environmental Monitoring and Assessment, 51, pp. 605-620.
Thomas, M., Florion, A., Chr?tien D.
Role of the O-phosphoserine clusters in the interaction of the bovine milk alpha(s1)-, beta-, kappa-caseins and the PP3 component with immobilized iron (III) ions
Biochimica et Biophysica Acta - Protein Structure and Molecular Enzymology, 1337 (1), pp. 149-159.
Bernos, E., Girardet, J.-M., Humbert, G., Linden, G.
Comparative enzymatic properties of GapB-encoded erythrose-4-phosphate dehydrogenase of Escherichia coli and phosphorylating glyceraldehyde-3- phosphate dehydrogenase
Journal of Biological Chemistry, 272 (24), pp. 15106-15112.
Boschi-Muller, S., Azza, S., Pollastro, D., Corbier, C., Branlant, G.
Urea recycling in the rumen of dairy goats: Effects of physiological stage and composition of intake
Small Ruminant Research, 23 (2-3), pp. 83-90.
Brun-Bellut, J.
15N enrichments of casein and plasma protein amino acids in cows ingesting 15N-labelled ammonium sulphate
Journal of Dairy Research, 64 (3), pp. 367-376.
Casseron, F., Rychen, G., Rubert-Aleman, X., Martin, G.J., Laurent, F.
Nitrogen-15 labelling of the nitrogenous fractions of milk using oral administration of labelled ammonium sulphate in the diet
Lait, 77 (2), pp. 307-316.
Colin-Schoellen, O., Claudon, C., Rychen, G., Antoine, J.M., Laurent, F., Vignon, B.
Animal Research, 46 (3), pp. 269-280.
Colin-Schoellen, O., Jurjanz, S., Laurent, F.
Influence of feeding level on growth, intraspecific weight variability and sexual growth dimorphism of Eurasian perch Perca fluviatilis L. reared in a recirculation system
Aquaculture, 157, pp. 1-9.
Fontaine, P., Gardeur, J.N., Kestemont, P., Georges, A.
Microbiology SGM, 143 (1), pp. 1587-1594.
Gonzalez-Marquez, H., Perrin, C., Bracquart, P., Guimont, C., Linden, G.
Biologically Active Factors in Bovine Milk and Dairy Byproducts: Influence on Cell Culture
Critical Reviews in Food Science and Nutrition, 37 (4), pp. 393-410.
Guimont, C., Marchall, E., Girardet, J.M., Linden, G.
Journal of Dairy Research, 64 (3), pp. 465-469.
Humbert, G., Guingamp, M.-F., Linden, G.
European Journal of Biochemistry, 248 (3), pp. 872-878.
Lecouvey, M., Frochot, C., Miclo, L., Orlewski, P., Driou, A., Linden, G., Gaillard, J.-L., Marraud, M., Cung, M.T., Vanderesse, R.
Letters in Peptide Science, 4 (4-6), pp. 359-364.
Lecouvey, M., Frochot, C., Miclo, L., Orlewski, P., Marraud, M., Gaillard, J.-L., Cung, M.T., Vanderesse, R.
Analysis of the genetic polymorphism between three Streptococcus thermophilus strains by comparing their physical and genetic organization
Microbiology, 143 (4), pp. 1335-1343.
Roussel, Y., Bourgoin, F., Guédon, G., Pébay, M., Decaris, B.
Isotopic enrichment kinetics of milk nitrogenous fractions in goats receiving a single intravenous injection of either L-(U-14C)-leucine or L-(1-13C)-leucine
Small Ruminant Research, 25 (1), pp. 23-31.
Rubert-Aleman, X., Rychen, G., Laurent, F.
Long-term consequences of neonatal exposure to diazepam on cerebral glucose utilization, learning, memory and anxiety
Brain Research, 766 (1-2), pp. 142-152.
Schroeder, H., Humbert, A.-C., Desor, D., Nehlig, A.
The long-term consequences of neonatal exposure to diazepam (DZP) on behavioral abilities and local cerebral glucose utilization (LCGU) in 12 brain regions involved in the control of memory and anxiety were studied in adult rats. Rat pups received a daily subcutaneous injection of 10 mg/kg DZP or of the dissolution vehicle from postnatal day (P) 2 to 21. Learning and memory were tested in P60-P70 rats over 5 consecutive days in a T maze and an eight-arm maze while anxiety and reaction to novelty were tested in a two- compartment box with a two-step staircase on the enriched side. LCGU was measured in the P60 rat by the quantitative autoradiographic [14C]deoxyglucose method. In the T maze, when performed without delay between the two trials, the rate of alternation was significantly lower in DZP- than in vehicle-exposed rats on the first 2 days of testing and similar in both groups on days 3-5. In the procedure with a 30 s intertrial delay, the rate of alternation was similar in DZP- and vehicle-treated rats on all days of testing. In the eight-arm maze, DZP-treated rats were more active, i.e., entered more arms per minute than control animals. The number of arms entered before the first error was lower on day 1 and higher on day 3 in DZP- compared to vehicle-exposed rats. In the two-compartment box, DZP-treated rats crossed more often and spent more time than controls on the lower step of the staircase while control rats made more matings and spent more time than DZP-exposed rats in the wall protected comer of the box. LCGU were decreased by early DZP exposure in six regions which were mammillary body, septum, visual and prefrontal cortices, dorsomedian caudate nucleus and mediodorsal thalamus. In conclusion, postnatal DZP treatment induced at adulthood an increase in activity, a delay in task acquisition but no learning-memory impairment and reduced the level of anxiety allowing active responding to novelty. These quite subtle behavioral changes were accompanied by discrete metabolic decreases in regions mediating anxiety, reflecting a change in the level of anxiety and emotionality.
Early chronic exposure to diazepam, cerebral metabolism and behavior: Long-term consequences. [Exposition chronique precoce au diazepam, metabolisme cerebral et comportement: Consequences a long terme chez le rat adulte]
Encephale, 23 (2), pp. 131-141.
Schroeder, H., Toniolo, A.-M., Desor, D., Nehlig, A.
The long-term consequences of a neonatal exposure to diazepam (DZP) on behavioral abilities and local cerebral metabolic rates for glucose (LCMRglc) in selected brain regions involved in the control of memory and anxiety were studied in adult rats. Rat pups received a daily subcutaneous injection of 10 mg/kg DZP or of the dissolution vehicle from postnatal day (P) 2 to 21. Learning and memory were tested in P60-P70 rats on 5 consecutive days in a T maze and an eight arm maze while anxiety and reaction to novelty were tested in a 2 compartment box with a 2 step staircase on one side. Social behavior was evaluated in a condition of restricted access to food. LCMRglcs were measured at P60 by the quantitative autoradiographic [14C]deoxyglucose method. In the T maze, when performed without delay between the 2 trials, the rate of alternation was significantly lower in DZP than in vehicle-exposed rats on the first 2 days of testing and similar in both groups on days 3-5. In the procedure with a 30 s intertrial delay, the rate of alternation was similar in DZP and vehicle-treated rats on all days of testing. In the eight arm maze, DZP-treated rats were more active, i.e. entering more arms per min than control animals. The number of arms entered before the first error was lower on day 1 and higher on day 3 in DZP compared to vehicle-exposed rats. In the 2 compartment box, DZP-treated rats crossed more often the lower step of the staircase and spent more time than controls on the 2 steps of the staircase while control rats made more rearings than DZP-exposed rats in the well protected corner of the box. LCMRglcs were decreased by early DZP exposure in several cortical regions, mammillary body, septum and dorsomedian caudate nucleus. In conclusion, an early chronic DZP treatment induces an increase in activity, only a delay but no impairment in learning and leads to a decrease in the level of anxiety and emotionality leading to an active response to novelty. These quite subtle behavioral changes are accompanied by discrete metabolic changes and probably reflect the state of hyperactivity/hyperarousal of these animals which could result from a change in the distribution, the sensitivity and/or function of GABA-BZD receptors.
The effect of pH and conductivity on the electric behaviour of Apteronotus albifrons (family Apteronotidae) in a pollution monitoring system.
Environmental Technology, 18, pp 1069-1083.
Thomas, M., Florion, A., Chr?tien, D.
An amplifiable and deletable locus of Streptomyces ambofaciens RP181110 contains a very large gene homologous to polyketide synthase genes
Microbiology, 142 (10), pp. 2815-2824.
Aigle, B., Schneider, D., Morilhat, C., Vandewiele, D., Dary, A., Holl, A.-C., Simonet, J.-M., Decaris, B.
Wheat phosphorus availability: 2 - In vivo study in broilers and pigs; relationship with endogenous phytasic activity and phytic phosphorus content in wheat
Journal of the Science of Food and Agriculture, 70 (1), pp. 69-74.
Barrier-Guillot, B., Casado, P., Maupetit, P., Jondreville, C., Gatel, F., Larbier, M.
Wheat phosphorus availability: 1 - in vitro study; factors affecting endogenous phytasic activity and phytic phosphorus content
Journal of the Science of Food and Agriculture, 70 (1), pp. 62-68.
Barrier-Guillot, B., Casado, P., Maupetit, P., Jondreville, C., Gatel, F., Larbier, M.
Characterization of a mosaic ISS1 element and evidence for the recent horizontal transfer of two different types of ISS1 between Streptococcus thermophilus and Lactococcus lactis
Gene, 178 (1-2), pp. 15-23.
Bourgoin, F., Guédon, G., Pébay, M., Roussel, Y., Panis, C., Decaris, B.
Changes affecting the Longissimus dorsi, Triceps brachii caput longum and Rectus femoris muscles of young Friesian bulls during meat ageing
Meat Science, 43 (3-4), pp. 335-344.
Bruas-Reignier, F., Brun-Bellut, J.
Comparison of the structures of wild-type and a N313T mutant of Escherichia coli glyceraldehyde 3-phosphate dehydrogenases: Implication for NAD binding and cooperativity
Journal of Molecular Biology, 257 (4), pp. 814-838.
Duee, E., Olivier-Deyris, L., Fanchon, E., Corbier, C., Branlant, G., Dideberg, O.
Release of free amino-acids during ageing in bovine meat
Meat Science, 44 (1-2), pp. 19-25.
Feidt, C., Petit, A., Bruas-Reignier, F., Brun-Bellut, J.
Rapid determination of fecal fat by Fourier transform infrared analysis (FTIR) with partial least-squares regression and an attenuated total reflectance accessory
Clinical Chemistry, 42 (12), pp. 2015-2020.
Franck, P., Sallerin, J.-L., Schroeder, H., Gelot, M.-A., Nabet, P.
Fecal lipid content is usually determined by titrimetric or gravimetric methods, but these methods are time consuming and involve dangerous solvents. We have developed a new method of measuring fecal lipids by Fourier transform infrared spectrometry (FTIR) with an attenuated total reflectance accessory that is fast and requires no solvents. The spectra of stools from 4000 to 750 cm-1 were analyzed, and the lipid concentrations were measured by using a calibration curve prepared by partial least-squares analysis of data from 34 stools. The linearity of the method was tested by mixing low-lipid stools with lipid-overloaded stools to give a range of 0.5-15% lipid. The prediction residual values were -0.49-0.78% for calibrators, and -2.55-2.34% for unknown samples. There was good agreement between the fecal lipids measured by gravimetric (x) and FTIR (y) methods:y = 0.87x + 5.5. The standard error of prediction was 1.07%.
PP3 component of bovine milk: A phosphorylated whey glycoprotein
Journal of Dairy Research, 63 (2), pp. 333-350.
Girardet, J.-M., Linden, G.
Milchwissenschaft, 51 (2), pp. 63-65.
Humbert, G., Guingamp, M.-F., Choukri, A., Linden, G.
Animal Research, 45 (5), pp. 467-476.
Jurjanz, S., Colin-Schoellen, O., Laurent, F.
Reproduction Nutrition Development, 36, pp. 414-415.
Perrin, E., Miclo, L., Driou, A., Gaillard, J.-L., Linden, G.
Analytical Communications, 33 (4), pp. 143-147.
Perrin, E., Miclo, L., Driou, A., Linden, G.
Amino acid composition analysis is sometimes used for the identification of peptides obtained from the hydrolysis of a protein of known sequence. Nevertheless, the interpretation of the analysis can be difficult if only one hydrochloric acid hydrolysis can be performed because of the partial destruction of some amino acids and the lack of cleavage of certain peptidic bonds. In this paper we propose combining the analysis of amino acids by two techniques (derivative UV spectrometry and retention time estimation) associated on-line with the purification step of the peptides (reversed-phase HPLC).
A set of 56 peptides from the peptic and chymotryptic hydrolysis of bovine αs1-casein (αs1-CN) were analysed in this manner. The difference between the theoretical and observed retention times was 1.9 min, for aromatic amino acids ratios the difference was 4.0%. The ambiguities coming from repeated residues in the sequence or the presence of Trp residues, destroyed by acidic hydrolysis, were solved and a fragment of the αs1-CN sequence could be attributed to each peptide.
Journal of Dairy Research, 63 (1), pp. 73-81.
Prin, C., El Bari, N., Montagne, P., Cuilliere, M.-L., Bene, M.-C., Faure, G., Humbert, G., Linden, G.
Lait, 76 (5), pp. 423-432.
Saulnier, F., Calco, M., Humbert, G., Linden, G.
Real-time detection of potassium cyanide pollution in surface waters using electric organ discharges wave emitted by the tropical fish, Apteronotus albifrons.
Environmental Technology, 17, pp. 561-574.
Thomas, M., Chr?tien, D., Florion, A., Terver, D.
Real-time biomonitoring of water contamination by cyanide based on analysis of the continuous electrical signal emitted by a tropical fish, Apteronotus albifrons.
Water Research, 30 (12), pp. 3083-3091.
Thomas, M., Chr?tien, D., Florion, A., Terver, D.
Effet de la nature de l'aliment concentré sur les performances zootechniques de vaches laitières recevant une ration complète
Annales de Zootechnie, 44, pp. 359-372
Colin-Schoellen, O., Jurjanz, S., Gardeur, J.N., Laurent, F.
Cow's milk proteins: a new raw material for drugs? [Les protéines du lait de vache : une nouvelle source de médicaments ?]
Cahiers de Nutrition et de Dietetique, 30 (6), pp. 359-364.
Driou, A., Jeantroux, M., Perrin, E., Miclo, L.
Structure of glycopeptides isolated from bovine milk component PP3
European Journal of Biochemistry, 234 (3), pp. 939-946.
Girardet, J.-M., Coddeville, B., Plancke, Y., Strecker, G., Campagna, S., Spik, G., Linden, G.
Characterization and distribution of two insertion sequences, IS1191 and iso-IS981, in Streptococcus thermophilus: Does intergeneric transfer of insertion sequences occur in lactic acid bacteria co-cultures?
Molecular Microbiology, 16 (1), pp. 69-78.
Guedon, G., Bourgoin, F., Pebay, M., Roussel, Y., Colmin, C., Simonet, J.M., Decaris, B.
Reproduction, nutrition, development, 35 (1), pp. 105-116.
Halbouche, M., Brun-Bellut, J.
Journal of Dairy Research, 62 (2), pp. 369-372. Cited 11 times.
Humbert, G., Guingamp, M.F., Choukri, A., Linden, G.
Proteolysis in samples of quarter milk with varying somatic cell counts. 1. Comparison of some indicators of endogenous proteolysis in milk.
Journal of dairy science, 78 (6), pp. 1289-1297.
Le Roux, Y., Colin, O., Laurent, F.
Proteolysis in samples of quarter milk with varying somatic cell counts. 2. Component PP3 and beta-casein-1P (f29-105 and f29-107) of the proteose-peptone fraction.
Journal of dairy science, 78 (6), pp. 1298-1305.
Le Roux, Y., Girardet, J.M., Humbert, G., Laurent, F., Linden, G.
International Journal of Peptide and Protein Research, 46 (2), pp. 186-192.
Miclo, L., Perrin, E., Driou, A., Mellet, M., Linden, G.
Le Lait, 75 (3), pp. 211-237.
Montagne, P., Cuillie?re, M.L., Marchal, E., El Bari, N., Montagne, M., Benali, M., Faure, G., Duheille, J., Humbert, G., Linden, G., Heurtaux, N., Blesche, J.L., Gosselin, D., Desmares, A., Delahaye, D.
Crystallization and preliminary X-ray diffraction studies of Escherichia coli glyceraldehyde-3-phosphate dehydrogenase
Acta Crystallographica - Section D Biological Crystallography, 51 (2), pp. 245-247.
Olivier, L., Buisson, G., Fanchon, E., Corbier, C., Branlant, G., Dideberg, O.
Journal of Chromatography B: Biomedical Applications, 664 (1), pp. 267-276.
Perrin, E., Miclo, L., Driou, A., Linden, G.
Effects of three microbial probiotics on postprandial portoarterial concentration differences of glucose, galactose and amino-nitrogen in the young pig
British Journal of Nutrition, 74 (1), pp. 19-26.
Rychen, G., Simoes Nunes, C.
Behavioral and metabolic consequences of neonatal exposure to diazepam in rat pups
Experimental Neurology, 131 (1), pp. 53-63.
Schroeder, H., Humbert, A.-C., Koziel, V., Desor, D., Nehlig, A.
The short-term consequences of a neonatal exposure to diazepam (DZP) on neurobehavioral development and postnatal changes in local cerebral metabolic rates for glucose (LCMRglcs) in selected regions were studied in rats. Rat pups received a daily subcutaneous injection of 10 mg/kg DZP or of the dissolution vehicle from Postnatal Day 2 (P2) to 21 (P21). DZP did not affect the static righting reflex tested at P4 but increased suspension time at P10 and time to complete a 180° pivoting on an inclined plane at P9. In a locomotor coordination test performed at P20, swimming or climbing on a vertical pole was not affected by DZP while the drug impaired the ability of the rat to place its hind-paws on the horizontal platform after climbing. Likewise, DZP induced marked decreases (19-45%) in LCMRglcs in most structures studied at P10, P14, and P21. The results of the present study show that neonatal DZP treatment induces motor deficits that appear to be quite subtle, to concern mainly posture and body balance. They are not apparent in tasks such as swimming or climbing but become obvious in more difficult tasks such as achieving a horizontal quadruped position on a platform after a climbing phase, Decreases in cerebral energy metabolism appear to be mainly located in areas controlling posture and body balance and are partly correlated with the locomotor impairments recorded in the present study.
Circular permutation within the coenzyme binding domain of the tetrameric glyceraldehyde-3-phosphate dehydrogenase from Bacillus stearothermophilus
Protein Science, 4 (5), pp. 994-1000.
Vignais, M.-L., Corbier, C., Mulliert, G., Branlant, C., Branlant, G.
Effects of supplemental phytase on performance and phosphorus utilisation in broiler chickens fed a low phosphorus diet without addition of inorganic phosphates.
British poultry science, 35 (2), pp. 273-280.
Broz, J., Oldale, P., Perrin-Voltz, A.H., Rychen, G., Schulze, J., Nunes, C.S.
Le Lait, 74, pp. 313-323.
Étienne, L., Girardet, J.-M., Linden, G.
TR-NOE NMR study of the E.coli wild-type GAPDH and its Thr313 mutant/NAD+ complex
PROTEIN PEPT.LETT., 1 (1), pp. 19-24.
Eyschen, J., Corbier, C., Vitoux, B., Branlant, G., Cung Manh Thong
Journal of Dairy Science, 77, pp. 1205-1215.
Girardet, J.-M., Saulnier, F., Driou, A., Linden, G., Coddeville, B., Spik, G.
Analytical Biochemistry, 222 (2), pp. 472-478.
Haissat, S., Marchal, E., Montagne, P., Humbert, G., Bene, M.C., Faure, G., Linden, G.
Physical and genetic map of Streptococcus thermophilus A054
Journal of Bacteriology, 176 (24), pp. 7413-7422.
Roussel, Y., Pebay, M., Guedon, G., Simonet, J.-M., Decaris, B.
Effects of early chronic diazepam treatment on incorporation of glucose and b-hydroxybutyrate into cerebral amino acids: Relation to undernutrition
International Journal of Developmental Neuroscience, 12 (5), pp. 471-484.
Schroeder, H., Collignon, A., Uttscheid, L., Pereira deVasconcelos, A., Nehlig, A.
The effects of early chronic diazepam (DZP) exposure on blood glucose and ketone body concentration and glucose and ß-hydroxybutyrate (ßHB) utilization for regional cerebral amino acidbiosynthesis were studied in suckling rats. The animals were treated from postnatal day 2 (P2) to 21 (P21) by a daily subcutaneous injection of 10 mg kg DZP or of the dissolution vehicle and studied at PS, P10, P14 and P21, together with an additional group of food-restricted rats obtained by an increase in litter size. DZP treatment induced a 9-26% decrease in body and brain weight. Under nutrition decreased body weight by 20-24% at all ages whereas brain weight was relatively spared. DZP and N-desmethyldiazepam concentrations decreased with age and were cleared from brain and plasma by 6-8 hrs after the injection. DZP decreased plasma glucose concentrations by 6-12% at P5, P14 and P21, whereas undemutrition did not change plasma glucose concentrations, except for a 7% decrease at P14. DZP treatment had no consequences on circulating concentrations of both ketone bodies while undernutrition increased their concentration by 45-362% at all ages. The conversion of [14C]glucose into cerebral amino acids was reduced by DZP at P5 and P10. The cerebral concentration of neurotransmitter arnino acids was not affected by DZP treatment which only increased the amount of neutral amino acids mainly in the cerebellum at PS and P10. After [U-14C]glucose injection, specific radioactivities of cerebral amino acids were mostly decreased by DZP from PS to P14 and significantly increased at P21. With [3-14C]13HB as a precursor, specific radioactivities of neurotransmitter amino acids were increased by DZP. In conclusion, P5 and P10 rats appear to be most sensitive to DZP effects whereas some tolerance to the drug seems to develop by P21. The lack of effects of DZP on blood ketone body concentrations compared to food restriction as well as the relative sparing of brain weight in undernourished rats confirms that the cerebral metabolic consequences of early DZP exposure on brain energy metabolism are mostly direct effects not mediated by sedation-induced undernutrition.
Early chronic exposure to diazepam, cerebral metabolism and behavior. I. Short-term effects. [Exposition chronique au diazépam, métabolisme cérébral et comportement. I. Effets à court terme]
Circulation et Metabolisme du Cerveau, 11 (4), pp. 343-365.
Schroeder, H., Desor, D., Nehlig, A.
The consequences of a chronic neonatal diazepam (DZP) treatment on the postnatal evolution of various aspects of cerebral energy metabolism and on behavior were studied in suckling rats. Animals were treated from postnatal day 2 to 21 by a daily subcutaneous injection of DZP (Valium injectable, Roche) at the dose of 10 mg/kg. Control animals received the same volume of the dissolution vehicle. Measurement of the incorporation of glucose carbon into cerebral amino acids and local cerebral glucose utilization were assessed at 5, 10, 14 and 21 days while behavioral testing was performed at 4, 9, 10 and 20 days. DZP exposure induced a decrease in body weight during the whole period studied as well as a delay in hair appearance. Circulating concentrations of glucose were reduced whereas those of ketone bodies were not affected by the treatment. Incorporation of glucose into amino acids was reduced at 5 and 10 days in the three brain regions studied and local cerebral glucose utilization was decreased essentially in sensory, motor and cortical areas during the same period of development. DZP treatment did not impair rat performances for the righting reflex, swimming or climbing a vertical rod. Conversely, DZP increased the time necessary to the rats to pivot by 180° on an inclined plane and altered their balance abilities, data that are in accordance with the decreases in functional activity in structures controlling balance and visuo-motricity. Finally, DZP prolonged the suspension time at 10 days, certainly as a result of its muscular relaxation properties.
Short- and long-term effects of neonatal diazepam exposure on local cerebral glucose utilization in the rat
Brain Research, 660 (1), pp. 144-153.
Schroeder, H., Nolte, A., Boyet, S., Koziel, V., Nehlig, A.
The short- and long-term consequences of a neonatal exposure to diazepam (DZP) on the postnatal changes in local cerebral metabolic rates for glucose (LCMRglcs) were studied by the quantitative autoradiographic [14C]2-deoxyglucose method in a total number of 66 brain structures of freely moving rats. Rat pups received a daily subcutaneous injection of 10 mg/kg DZP, of the dissolution vehicle or of saline from postnatal day 2 (P2) to 21 (P21). The animals were studied at 4 ages, P10, P14, P21 and P60; DZP induced a decrease in LCMRglcs which was restricted to 13 areas at P10, mainly sensory and limbic regions. At P14, the treatment had significant metabolic effects on 48 structures belonging to all functional systems. By P21, 23 brain areas were still affected by the treatment, mainly sensory, limbic and motor areas. At P60, i.e. at about 40 days after the end of drug exposure, LCMRglcs still decreased in 14 brain regions which were mainly sensory and limbic structures. The structures most sensitive to both short- and long-term consequences of the anticonvulsant treatment are mammillary body, limbic cortices and sensory regions. The dissolution vehicle increased LCMRglcs in few brain regions at P14 and P60, whereas it decreased metabolic levels in 5 brain regions at P21. The results of the present study show that the brain appears to be particularly vulnerable to the treatment at P14, period of active brain growth, whereas by P21, the drug is more actively metabolized and a tolerance to the treatment may occur. The long-term effects of the treatment are in good accordance with the well-known effects of DZP on anxiety, sedation and memory. The structures most sensitive to early neonatal DZP exposure are the mammillary body, limbic cortices and sensory regions that all contain a high density of benzodiazepine binding sites.
Le recours biologique pour la surveillance de la qualité des eaux.
Ichtyophysiologica Acta, 17, pp 167-188.
Thomas, M., Terver, D.
Effect of heat drying temperature on the nutritive value of corn in chickens and pigs
Animal Feed Science and Technology, 41 (2), pp. 149-159.
Barrier-Guillot, B., Zuprizal, Jondreville, C., Chagneau, A.M., Larbier, M., Leuillet, M.
An experiment was conducted to evaluate the effect of heat drying temperature on the nutritive value of corn for roosters and pigs. Two batches of a French cultivar grown in two consecutive years were treated by a two-step drying process. The first temperature was used to remove approximately two-thirds of the moisture, and the second was applied in order to obtain a final grain moisture of approximately 15%. Six treatments each year were compared: for Corn 1, control, 80-80, 100-90, 120-100, 140-110 and 160-120°C; for Corn 2, control, 100-90, 120-100, 130-105, 140-110 and 160-120°C. True metabolizable energy and true digestibility of protein and amino acids of both corns, and digestibility of starch in Corn 2 only, were measured with six intact 1-year old (Isa Brown) roosters per treatment. Apparent ileal digestibility of protein and amino acids of Corn 2 was determined with four castrated male (Large White) pigs weighing between 60 and 80 kg and fitted with an end-to-end ileo-rectal anastomosis. The heat drying processing had no effect on the chemical composition of the corns. In digestibility experiments with roosters, the optimal heat drying temperature to obtain the best nutritive value (true metabolizable energy and digestibility of protein and lysine) was at 120-100°C. However, treatment temperature had no effect on the digestibility of starch. In digestibility experiments with pigs, the apparent ileal digestibility of protein decreased regularly with temperature from the first treatment (100-90°C). For roosters and pigs, artificial drying at high temperatures had detrimental effects on the nutrient value of grain, especially for lysine. In our experimental conditions, the inlet air temperature during drying should never exceed 130°C.
Large genomic rearrangements of the unstable region in Streptomyces ambofaciens are associated with major changes in global gene expression
Molecular Microbiology, 10 (4), pp. 759-769.
Dary, A., Kaiser, P., Bourget, N., Thompson, C.J., Simonet, J.-M., Decaris, B.
Stable successional patterns of aquatic hyphomycetes on leaves decaying in a summer cool stream.
Mycological Research, 97 (2), pp. 163-172.
Gessner, M.O., Thomas, M., Jean-Louis, A.M., Chauvet,E.
Study of mechanism of lipolysis inhibition by bovine milk proteose-peptone component 3.
Journal of dairy science, 76 (8), pp. 2156-2163.
Girardet, J.M., Linden, G., Loye, S., Courthaudon, J.L., Lorient, D.
Mitogenic activity of hydrophobic fractions of proteose-peptone from cows', ewes' and goats' milk measured with MARK3 hybridoma culture
Journal of Dairy Research, 60, pp. 443-448.
Mati, A., Moulti-Mati, F., Girardet, J.-M., Fokou, E., Belleville-Nabet, F., Nabet, P., Linden, G.
Strain characterization, genome size and plasmid content in the Lactobacillus acidophilus group (Hansen and Mocquot)
Journal of Applied Bacteriology, 74 (5), pp. 549-556.
Roussel, Y., Colmin, C., Simonet, J.M., Decaris, B.
Effects of a microbial probiotic (Sporolactobacillus P44) on postprandial porto-arterial concentration differences of glucose, galactose and amino-nitrogen in the growing pig
Reproduction Nutrition Development, 33 (6), pp. 531-539.
Rychen, G., Simoes Nunes, C.
Amplification of a particular DNA sequence in Streptomyces ambofaciens RP181110 reversibly prevents spiramycin production
Research in Microbiology, 143 (1), pp. 99-112.
Dary, A., Bourget, N., Girard, N., Simonet, J.-M., Decaris, B.
Composition azotée et caractéristiques technologiques du lait de vache en relation avec la nature et le niveau d'apport de l'aliment concentré
Lait, 72, pp. 175-183
Laurent, F., Coomans, D., Gardeur, J.N., Vignon, B.
High-frequency deletion involving closely spaced rRNA gene sets in Streptococcus thermophilus
FEMS Microbiology Letters, 98 (1-3), pp. 51-55.
Pebay, M., Roussel, Y., Simonet, J.-M., Decaris, B.
Effects of acute administration of a new trimethylxanthine derivative, S 9977-2, on local cerebral blood flow and glucose utilization in the rat
European Journal of Pharmacology, 220 (2-3), pp. 217-229.
Schroeder, H., Dumont, I., Boyet, S., Mocaer, E., Nehlig, A.
S 9977-2 is a new trimethylxanthine derivative with promnesic properties. Its effects on cerebral glucose utilization and blood flow were studied by means of quantitative autoradiography. S 9977-2 was injected intravenously into adult rats at doses of 0.1, 1.0 and 10 mg/kg. At 0.1 mg/kg, S 9977-2 induced a significant increase in cerebral glucose utilization over control values in two white matter areas and in the vestibular nucleus. At 1.0 mg/kg, glucose utilization was affected in 14 areas out of the 63 studied, mainly limbic regions such as the hippocampus, raphe nuclei and locus coeruleus, as well as some posterior areas. Conversely, after the injection of 10 mg/kg S 9977-2, cerebral glucose utilization was similar to that of control rats. At the three doses tested, S9977-2 did not induce any significant variation in local rates of cerebral blood flow compared to those of controls. Likewise, S 9977-2 did not change the level of coupling between cerebral blood flow and metabolism, except at 10 mg/kg, where a relative hypoperfusion at a constant metabolic level was recorded. These data show that, at 1.0 mg/kg, S 9977-2 increased glucose utilization in hippocampal areas, an effect which may be related to the promnesic properties of this compound at the same dose. Moreover, at low doses, the lack of change in the level of coupling between cerebral blood flow and metabolism is indicative of the rather selective action of this compound, compared to that of caffeine. Thus S 9977-2 should have therapeutic effects, mainly via its promnesic properties, without having many side effects.
Genetic instability in Streptomyces ambofaciens: inducibility and associated genome plasticity
Gene, 115 (1-2), pp. 49-54
Simonet, J.-M., Schneider, D., Volff, J.-N., Dary, A., Decaris, B.
Tissue protein synthesis in lactating and dry goats
British Journal of Nutrition, 66 (3), pp. 451-465.
Baracos, V.E., Brun-Bellut, J., Marie, M.
Effects of the acute administration of a new trimethylxanthine derivative, S 9977-2, on cerebral blood flow and energy metabolism in the rat. [Effets de l'administration aigue d'un nouveau dérvié des triméthylxanthines, le S 9977-2, sur le débit sanguin et le métabolisme énergétique cérébral chez le rat]
Circulation et Metabolisme du Cerveau, 8 (3), pp. 157-174.
Dumont, I., Schroeder, H., Koziel, V., Mocaer, E., Nehlig, A.
Journal of Dairy Research, 58, pp. 85-98.
Girardet, J.-M., Mati, A., Sanogo, T., Étienne, L., Linden, G.
Le Lait, 71, pp. 259-273.
Mati, A., Girardet, J.-M., Xenakis, D., Linden, G.
International Journal of Biochemistry, 23 (3), pp. 377-381.
Nedjar, S., Humbert, G., Le Deaut, J.Y., Linden, G.
Le Lait, 71, pp. 511-518.
Saulnier, F., Ferrero, F., Choukri, A., Girardet, J.-M., Linden, G.
Influence of early chronic phenobarbital treatment on cerebral arteriovenous differences of glucose and ketone bodies in the developing rat
International Journal of Developmental Neuroscience, 9 (5), pp. 453-461.
Schroeder, H., Bomont, L., Nehlig, A.
The influence of an early chronic phenobarbital treatment on cerebral arteriovenous differences of glucose, lactate, pyruvate, ß-hydroxybutyrate and acetoacetate was studied in suckling rats. The animals were treated from day 2 to 21 after birth by a daily injection of 50 mg/kg phenobarbital or by saline and were studied at 10, 14 and 21 days. Phenobarbital treatment induced a decrease in cerebral arteriovenous difference of glucose at P14 and no change at P10 and P21. The barbiturate did not have any influence on cerebral arteriovenous difference of lactate and pyruvate at the three stages studied. Cerebral uptake of ß-hydroxybutyrate was unchanged at P10 and increased by two-fold at P14 and by threefold at P21 by phenobarbital. Cerebral arteriovenous difference of acetoacetate was low and did not change with the pharmacological treatment. At P14 and P21, the calculated amount of oxygen used by the brain for the oxidation of ketone bodies was twice as high in barbiturate- as in saline-treated rats and reached values of 47 and 16% respectively in phenobarbital-exposed animals. In addition, the barbiturate seemed to affect the carrier process of ß-hydroxybutyrate from blood to brain. The results of the present study are in good agreement with previous data from our laboratory showing that an early chronic phenobarbital treatment is able to induce a shift in the cerebral energy metabolism balance in favor of ketone bodies.
Characterization of a family of multimeric ccc molecules of amplified chromosomal DNA in Streptomyces ambofaciens DSM 40697
FEMS Microbiology Letters, 78 (1), pp. 25-32.
Simonet, B., Dary, A., Decaris, B., Simonet, J.M.
Probing the coenzyme specificity of glyceraldehyde-3-phosphate dehydrogenases by site-directed mutagenesis
Biochemistry?, 29 (30), pp. 7101-7106.
Corbier, C., Clermont, S., Billard, P., Skarzynski, T., Branlant, C., Wonacott, A., Branlant, G.
The nicotamide subsite of glyceraldehyde-3-phosphate dehydrogenase studied by site-directed mutagenesis
Biochimie, 72 (8), pp. 545-554.
Corbier, C., Mougin, A., Mely, Y., Adolph, H.W., Zeppezauer, M., Gerard, D., Wonacott, A., Branlant, G.
Site-directed mutagenesis of glyceraldehyde-3-phosphate dehydrogenase reveals the role of residue Ser148
Protein Engineering, 2 (7), pp. 559-562.
Corbier, C., Branlant, C., Wonacott, A., Branlant, G.
Molecular cloning of a nosiheptide resistance gene from Streptomyces actuosus [CLONAGE D'UN GENE DE RESISTANCE AU NOSIHEPTIDE DE STREPTOMYCES ACTUOSUS]
Comptes Rendus de l'Academie des Sciences - Serie III, 308 (2), pp. 35-41.
Dary, A., Simonet, B., Simonet, J.-M., Decaris, B.
Milchwissenschaft, 44 (11), pp. 692-696.
Girardet, J.-M., Paquet, D., Linden, G.
Effects of caffeine and doxapram administration on local cerebral glucose utilization in the rat. [Effets de l'administration de caféine et de doxapram sur l'utilisation cérébrale locale de glucose chez le rat]
Circulation et Metabolisme du Cerveau, 6 (2), pp. 160-173.
Schroeder, H., Boyet, S., Nehlig
Effects of caffeine and doxapram perfusion on local cerebral glucose utilization in conscious rats
European Journal of Pharmacology, 167 (2), pp. 245-254.
Schroeder, H., Boyet, S., Nehlig, A.
The quantitative autoradiographic 2-[14C]deoxyglucose method was used to measure the effects of a continuous infusion of the respiratory stimulants, caffeine or doxapram, 18 mg/kg per h, on local cerebral glucose utilization in the adult male rat. Local cerebral glucose utilization was measured in 54 cerebral structures from different systems. Caffeine induced widespread increases in energy metabolism, resulting in a significant increase in glucose utilization in 25 structures out of the 54 studied. These increases were distributed within all systems studied, sensory, extrapyramidal motor, limbic and hypothalamic systems. in addition, caffeine induced a non-significant, 10-15%, increase in local cerebral glucose utilization in central respiratory areas. Doxapram infusion did not change the rates of glucose utilization in any of the structures. The rates of local cerebral glucose utilization were significantly lower after doxapram than after caffeine exposure in five cerebral areas, among which were three central respiratory areas. The results confirm the absence of side-effects of doxapram as compared to caffeine when used as respiratory stimulant, especially in neonates. These results also favor a preferentially central action of caffeine on respiratory areas and a more peripheral action of doxapram on chemoreceptors, at least at therapeutic levels.
Role of the histidine 176 residue in glyceraldehyde-3-phosphate dehydrogenase as probed by site-directed mutagenesis
Biochemistry, 28 (6), pp. 2586-2592.
Soukri, A., Mougin, A., Corbier, C., Wonacott, A., Branlant, C., Branlant, G.
Effect of dietary restriction on the flow of organic matter and nitrogen in the digestive tract of goats [Effet d'une restriction alimentaire sur le flux de matiere organique et d'azote dans le tube digestif des caprins.]
Reproduction Nutrition Developpement, 28 Suppl 1, pp. 123-124.
Brun-Bellut, J., Halbouche, M., Vignon, B.
Use of site-directed mutagenesis to probe the role of Cys149 in the formation of charge-transfer transition in glyceraldehyde-3-phosphate dehydrogenase.
Protein Engineering, 2 (1), pp. 45-48.
Mougin, A., Corbier, C., Soukri, A., Wonacott, A., Branlant, C., Branlant, G.
Inter individual variability and repeatability in the prediction of the voluntary food intake of dairy cows
World Revue of Animal Production, 3, pp. 77-82.
Gardeur, J.N., Vignon, B.
Effects of early chronic phenobarbital treatment on the maturation of energy metabolism in the developing rat brain. II. Incorporation of ß-hydroxybutyrate into amino acids
Developmental Brain Research, 36 (2), pp. 231-236.
Pereira De Vasconcelos, A., Schroeder, H., Nehlig, A.
The influence of phenobarbital (PhB) on the utilization of ß-hydroxybutyrate by the cerebral cortex and the cerebellum was studied in rats during postnatal maturation. The animals were treated from day 2 to day 35 after birth either by a daily injection of 50 mg/kg PhB or by saline. The rats were studied at 5 postnatal stages: 7, 10, 14, 21 and 35 days. Plasma ß-hydroxybutyrate and acetoacetate levels reached their peak values between 10 and 14 days after birth. The concentration of both ketone bodies was significantly higher in PhB- than in saline-treated rats between 10 and 35 days after birth. The total incorporation of [3-14C]ß-hydroxybutyrate into amino acids reached a peak value at 14 days after birth and was down to very low values at 35 days. It was higher in PhB- than in saline-treated rats. The specific radioactivity values of glutamate, glutamine, aspartate and GABA were significantly higher in PhB- than in saline-treated especially at 10 days after birth. These results demonstrate that a PhB treatment induces an increase in brain ketone body utilization in neonate rats, which is likely to balance the decrease in brain glucose utilization induced by this pharmacological treatment.
Annales De Zootechnie, 33, 2, 25-39.
Brun-Bellut J., Blanchart G., Vignon B.
Microbiologie - Aliments - Nutrition, 2, 301-316.
Brun-Bellut, J., Laurent, F., Vignon, B.
Journal of Dairy Science, 66, 2271-2277.
Humbert G, Brun-Bellut J., Mora T., Alais C.
Reproduction Nutrition Developpement, 20 (5 B), pp. 1731-1737.
Blanchart, G., Brun-Bellut, J., Vignon, B.
Journal of Dairy Research, 46 (3), pp. 559-571.
Humbert, G., Alais, C.
Cahiers de Nutrition et de Dietetique, 14 (3), pp. 203-205.
Humbert, G., Grilliat, J.P., Moneret-Vautrin, D.
Annales de la nutrition et de l?alimentation, 32 (2-3), pp. 511-521.
Alais, C., Lorient, D., Humbert, G.
Biochimie, 58 (7), pp. 871-873.
Lorient, D., Humbert, G., Alais, C.