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278 résultat(s) trouvé(s)
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Fournier A - Feidt C - Travel A - Le Bizec B - Marchand P - Jondreville C
Relative bioavailability to laying hens of indicator polychlorobiphenyls present in soil
Transfer of indicator polychlorobiphenyls (PCBs) from soil into hen eggs may occur in hens reared outdoor, which ingest significant amounts of soil. This transfer depends on the bioavailability of the ingested compounds. The impact of soil on the bioavailability of indicator PCBs was assessed by means by a relative bioavailability (RBA) trial, in which their deposition in egg yolk and in abdominal fat, in response to their ingestion through contaminated-soil and through spiked-oil were compared. A sandy soil (709 µg indicator PCBs kg-1 dry matter) was collected in the vicinity of a former fire involving treated wood. Twenty-eight laying hens were individually housed and fed one of the seven experimental diets during 14 d. The seven experimental diets were an uncontaminated control diet, three diets in which contaminated soil was introduced at levels of 3%, 6% and 9% and three diets in which spiked oil was introduced to achieve similar levels and profile of contaminants. Yolk, abdominal fat and liver were collected at the end of exposure. Indicator PCBs were extracted by ASE (Accelerated Solvent Extraction) and analyzed by GC–HMRS. Within each ingested matrix, the concentration of indicator PCBs in yolk and in abdominal fat linearly increased with the amount of indicator PCB ingested (P < 0.001). Except for PCB 28, the slopes of the responses to soil and to oil could not be differentiated (P > 0.1). RBA estimates did not differ from 1for all indicator PCBs except for PCB 28, for which it was 0.58–0.59. Measurements performed on liver confirm these conclusions. © 2012 Elsevier Ltd. All rights reserved.

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Fournier A - Feidt C - Marchand P - Le Bizec B - Venisseau A - Sellier N - Engel E - Ratel J - Travel A - Jondreville C
Kinetic study of γ-hexabromocyclododecane orally given to laying hens (Gallus domesticus)
Environmental Science and Pollution Research
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. © Springer-Verlag 2011.

Sous presse, 2012
DOI 10.1007/s11306-012-0415-7
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Moyon T - La Marec F - Qannari El M - Vigneau E - Le Plain A - Courant F - Antignac JP - Parnet P - Alexandre-Gouabau MC
Statistical strategies for relating metabolomics and proteomics data: a real case study in nutrition research area
The current investigations were carried out in the context of a nutritional case study aiming at assessing the postnatal impact of maternal dietary protein restriction during pregnancy and lactation on rat offspring plasma metabolome and hypothalamic proteome. Although data generated by different ‘‘Omics’’ technologies are usually considered and analyzed separately, their interrelation may offer a valuable opportunity for assessing the emerging ‘integrated biology’ concept. The overall strategy of analysis first investigated data pretreatment and variable selection for each dataset. Then, three multivariate analyses were applied to investigate the links between the abundance of metabolites and the expression of proteins collected on the same samples. Unfold principal component analysis and regularized canonical correlation analysis did not take into account the presence of groups of individuals related to the intervention study. On the contrary, the predictive MultiBlock Partial Least Squares method used this information. Regularized canonical correlation analysis appeared as a relevant approach to investigate of the relationships between the two datasets. However, in order to highlight the molecular compounds, proteins and metabolites, associated in interacting or common metabolic pathways for the experimental groups, MultiBlock partial least squares was the most appropriate method in the present nutritional case study. © Springer Science+Business Media, LLC 2012.

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Bellet V - Hernandez-Raquet G - Dagnino S - Sérée L - Pardon P - Bancon-Montigny C - Fenet H - Creusot N - Aït-Aïssa S - Cavailles V - Budzinski H - Antignac JP - Ballaguer P
Occurrence of androgens in sewage treatment plants influents is associated with antagonist activities on other steroid receptors
Water Research
The occurrence of endocrine disrupting chemicals such as estrogens in raw urban sewage is well documented. By contrast, the presence of other steroidal activities in wastewater has been poorly studied, although they can cause undesirable biological responses in the environment. In this work, extracts of raw wastewater were tested for agonist and antagonist activities on estrogen, androgen, progesterone, mineralocorticoid and glucocorticoid receptors. We detected strong estrogenic activities that correlated well with the concentration of natural estrogens (estrone, estriol and 17b-estradiol) measured by chemical analysis. We also measured strong androgenic activities which were not due to estrogen receptor ligands based on the use of recombinant estrogen receptor a affinity columns. Several molecules with androgenic activities were identified in wastewater samples, testosterone, dihydrotestosterone and epiandrosterone being the most abundant. However, they explain only a small part of the detected androgenic activity, as indicated by the comparison of the detected biological responses with the results of the targeted chemical analysis. Finally, we found that our samples also contained strong antagonist activities on progesterone, glucocorticoid and mineralocorticoid receptors. Very interestingly, we identified pregnenolone (the precursor to all steroid hormones in humans) as a major endocrine disrupting chemical which accounts for most of the antimineralocorticoid activities present in raw wastewater. In conclusion, this study demonstrates the occurrence of androgen agonists as well as other steroid receptor antagonists such as pregnenolone in raw wastewater. Further research is needed to assess the fate of such compounds during sewage treatment and their potential effect on living organisms. © 2012 Elsevier Ltd. All rights reserved.

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Anizan S - Bichon E - Di Nardo D - Monteau F - Cesbron N - Antignac JP - Le Bizec B
Screening of androstenedione misuse in cattle by LC-MS/MS profiling of glucuronide and sulfate steroids in urine
The use of anabolic agents in food producing animals is prohibited within the European Union since 1988. The illegal use of natural steroid hormones control is however still a current challenge, especially regarding the limitations of existing screening methods. In this context, the present study aimed to develop a new screening approach based on the emerging ‘untargeted profiling’ concept, but with a special emphasis on steroids phase II conjugated metabolites, in the scope of revealing potential biomarkers signing a fraudulent administration of 4-androstenedione. After extraction and separation of the urinary glucuronide and sulfate steroid fractions, each one was analyzed separately by UPLC–MS/MS using the precursor ion scan acquisition mode. This approach was carried out in order to monitor product ion characteristic of sulfate (m/z 97) and glucuronide (m/z 113) functional groups, and then to fish for any potential conjugated steroid leading to these ionic species after fragmentation. After statistical analysis, 86 metabolites (33 from steroid compounds and 53 from other unknown substances) were highlighted as potential biomarkers of 4-androstenedione abuse. After application of several robustness criteria, 26 metabolites (whom 5 were unambiguously structurally identified), were finally selected to build a statistical model which could be used as new diagnostic tool for screening purposes. © 2011 Elsevier B.V. All rights reserved.

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Qannari El M - Vigneau E - Moyon T - Courant F - Antignac JP
A simple continuum approach for canonical correlation analysis; applications to “omics” data
Curent Analytical Chemistry

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Kadar H - Veyrand B - Barbarossa A - Legrand A - Boquien CY - Durand S - Monteau F - Le Bizec B - Antignac JP
Development of an analytical strategy based on liquid chromatography - high resolution mass spectrometry for measuring perfluorinated compounds in human breast milk: application to the generation of preliminary data regarding perinatal exposure in France
Perfluorinated compounds (PFCs) are man-made chemicals for which endocrine disrupting properties and related possible side effects on human health have been reported, particularly in the case of an exposure during the early stages of development, (notably the perinatal period). Existing analytical methods dedicated to PFCs monitoring in food and/or human fluids are currently based on liquid chromatography coupled to tandem mass spectrometry, and were recently demonstrated to present some limitations in terms of sensitivity and/or specificity. An alternative strategy dedicated to the analysis of fourteen PFCs in human breast milk was proposed, based on an effective sample preparation followed by a liquid chromatography coupled to high resolution mass spectrometry measurement (LC–HRMS). This methodology confirmed the high interest for HRMS after negative ionization for such halogenated substances, and finally permitted to reach detection limits around the pg mL-1 range with an outstanding signal specificity compared to LC–MS/MS. The proposed method was applied to a first set of 30 breast milk samples from French women. The main PFCs detected in all these samples were PFOS and PFOA with respective median values of 74 (range from 24 to 171) and 57 (range from 18 to 102) pg mL-1, respectively. These exposure data appeared in the same range as other reported values for European countries. © 2011 Elsevier Ltd. All rights reserved.

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Alexandre-Gouabau MC - Courant F - Le Gall G - Moyon T - Darmaun D - Parnet P - Coupe B - Antignac JP
Offspring metabolomic response to maternal protein restriction in a rat model of intrauterine growth restriction (IUGR)
Journal of Proteome Research
Intrauterine growth restriction (IUGR), along with postnatal growth trajectory, is closely linked with metabolic diseases and obesity at adulthood. The present study reports the time-dependent metabolomic response of male offspring of rat dams exposed to maternal adequate protein diet during pregnancy and lactation (CC) or protein deprivation during pregnancy only (IUGR with rapid catch-up growth, RC) or through pregnancy and lactation (IUGR with slow postnatal growth, RR). Plasma LC-HRMS metabolomic fingerprints for 8 male rats per group, combined with multivariate statistical analysis (PLS-DA and HCA), were used to study the impact of IUGR and postnatal growth velocity on the offspring metabolism in early life (until weaning) and once they reached adulthood (8 months). Compared with CC rats, RR pups had clear-cut alterations in plasma metabolome during suckling, but none at adulthood; in contrast, in RC pups, alterations in metabolome were minimal in early life but more pronounced in the long run. In particular, our results pinpoint transient alterations in proline, arginine, and histidine in RR rats, compared to CC rats, and persistent differences in tyrosine and carnitine, compared to RC rats at adulthood. These findings suggest that the long-term deregulation in feeding behavior and fatty acid metabolism in IUGR rats depends on postnatal growth velocity. © 2011 American Chemical Society

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Vanden Bussche J - Kiebooms J - De Clercq N - Deceuninck J - Le Bizec B - De Brabander H - Vanhaecke L
Feed or food responsible for the presence of low-level thiouracil in urine of livestock and humans?
Journal of Agricultural and Food Chemistry
In recent years, questions have been raised on the possible semi-endogenous status of the alleged xenobiotic thyreostatic drug thiouracil; thiouracil has been detected in the urine of various animals (livestock and domesticated) at concentrations between 1 and 10 μg L-1 and also in human urine. Although several studies suggest Brassicaceae-derived feed as potential origin, no traces of thiouracil have been detected in feed so far. Therefore, the aimof this study was to elucidate the origin of thiouracil in the urine of livestock and humans. To this purpose various Brassicaceae feed and food sources (e.g., rapeseed, rapeseed coarse meal, cabbage, cauliflower, broccoli) were investigated for the presence of thiouracil. In addition, the impact of the Brassicaceae-related β-thioglucosidase enzyme was evaluated. This myrosinase enzyme appeared to be crucial, because without its catalyzed hydrolysis no thiouracil could be detected in the various Brassicaceae-derived samples. Therefore, a sample pretreatment with incorporated enzymatic hydrolysis was developed after ensuring the quality performance of the extracted myrosinase mixture with a single-point glucose assay. Upon enzymatic hydrolysis and LC-MS2 analysis, thiouracil was successfully detected in samples of traditional rapeseed, rapeseed-‘00’ variety coarse meal (values of erucic acid <2% and glucosinolates <25 μmol g-1), and rapeseed cake at 1.5, 1.6, and 0.4 μg kg-1, respectively. As for the food samples, broccoli and cauliflower displayed thiouracil concentrations of 6.0 and <1.0 μg g-1, respectively. To the best of the authors' knowledge this study is the first to report the presence of naturally occurring thiouracil in feed and food samples. Future research should investigate the pathway of thiouracil formation and identify its possible precursors. © 2011 American Chemical Society.

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Boyard-Kieken F
Comparison of different liquid chromatography stationary phases in LC-HRMS metabolomics for the detection of recombinant growth hormone doping control
Journal of Separation Science
Growth hormone (GH) is a polypeptide suspected of being used in horse racing to speed up physical performances. Despite scientific advances in the recent years, the control of its administration remains difficult. In order to improve it, a metabolomics study through LC-high resolution mass spectrometry measurements was recently initiated to assess the metabolic perturbations caused by recombinant equine growth hormone administration. Few tens of ions not identified structurally were highlighted as compounds responsible for the modification of metabolic profiling observed in treated animals. This previous work was based on the use of Uptisphere Strategy NEC as the chromatographic column. In parallel, more and more metabolomics studies showed the interest of the use of new chromatographic supports such as hydrophilic interaction chromatography for the analysis of polar compounds. It is in this context that an investigation was conducted on Uptisphere HDO and Luna hydrophilic interaction chromatography stationary phases to generate and process urinary metabolomics fingerprints, which could allow to establish a comparison with Uptisphere Strategy NEC. The chromatographic column the most adapted for the detection of new biomarkers of GH administration has been used to set up a relevant statistical model based on the analysis of more than hundred biological samples. & 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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