37 research outputs found
First insights into serum metabolomics of trenbolone/estradiol implanted bovines; screening model to predict hormone-treated and control animalsâ status
International audienceThe use of anabolic agents in livestock production is a subject of much concern. Although prohibited for more than 20 years within the EU, growth promoting practices are still widely suspected. To meet the current challenges for detecting illicit practices, âomicsâ strategies have recently been demonstrated as important new investigative tools. These investigations, based on the observation of physiological disturbances, mainly in urine, demonstrated the possibility to monitor biomarkers enabling high throughput determination of animal status in terms of hormonal treatment. In this context, serum was investigated for the first time as an alternative and potential complementary sample type. A metabolomic approach based on liquid chromatography coupled to high resolution mass spectrometry, was exploited in order to, highlight metabolic perturbations in serum of Revalor-XSÂź (trenbolone acetate/estradiol) implanted bovines. Univariate and multivariate statistical analyses were carried out to establish descriptive and predictive models. These models enabled the discrimination of anabolised from control animals, and highlighted a number of metabolites which contributed the most in the observed discrimination. Further, a screening model combining a set of selected markers intensities was generated and it successfuly classified animals according to their status, up to 4 weeks post Revalor-XSÂź implant. This research indicates, for the first time, that serum metabolomics has an important role in screening to detect for anabolic misuse in bovines.</p
Effect of oral exposure to polycyclic aromatic hydrocarbons on goat's milk contamination
The impact of chronic exposure to polycyclic aromatic hydrocarbons (PAHs) on milk contamination was evaluated by oral administration of a mixture of fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo(k)fluorene, benzo(a)pyrene and benzo(g,h,i)perylene at 0.02 mg/kg to lactating goats for 28 days. We analysed PAHs and their major metabolites in milk by gas chromatography-mass spectrometry. The results evidence several major points: (1) benzo(k)fluorene, benzo(a)pyrene and benzo(g,h,i)perylene were not detected in the milk; (2) unexpectedly, the concentration of fluorene, phenanthrene, anthracene, fluoranthene, pyrene and chrysene did not change with time; (3) monohydroxylated PAH metabolites (-OH), namely 2-OH-fluorene, 3-OH-phenanthrene and 1-OH-pyrene were detected shortly after administration. The concentrations of 2-OH-fluorene and 3-OH-phenanthrene reached, respectively, maxima of 0.41 and 0.22 ng/mL during the first exposure week, whereas the concentration of 1-OH pyrene increased to reach a maximum of 0.97 ng/mL on day 14, then slightly decreased during the last two exposure weeks. Those findings suggest a lack of activation of a metabolism that could lead to an excretion of PAHs into milk under native forms. However, a slight increase in concentration could induce the metabolism, which should lead to an increase in the excretion of metabolites into the milk. In spite of the absence of a significant transfer of parent PAHs to milk, the appearance of metabolites in milk raises questions of their impact on human health
Stratégie de mesure non ciblée de type métabolomique (couplage LC-HRMS ) pour identifier différents groupes de composés bioactifs accumulés dans les mollusques bivalves
La bioactivitĂ© des toxines du phytoplancton qui sâaccumulent dans les coquillages est presque toujours Ă©valuĂ©e sur modĂšle animal (test souris). MalgrĂ© ses avantages, la capacitĂ© de ce test Ă expliquer la nature de cette bio-activitĂ© reste limitĂ©e. Par ailleurs, le contrĂŽle sanitaire actuellement basĂ© sur une mĂ©thode ciblĂ©e dâidentification et de quantification dâun ensemble de toxines connues ne permet pas de dĂ©tecter des toxines encore inconnues. Afin de rĂ©pondre Ă ce besoin de caractĂ©risation de substances toxiques inconnues, une nouvelle approche de profilage chimique diffĂ©rentiel et non ciblĂ©, de type mĂ©tabolomique, a Ă©tĂ© proposĂ©e. Les 2 extraits sĂ©lectionnĂ©s sont ceux ayant montrĂ© une toxicitĂ© positive chez la souris, sans que les substances potentiellement responsables de cet effet toxique nâaient Ă©tĂ© rĂ©vĂ©lĂ©es par des mesures ciblĂ©es
Alteration of microcystin-LR by hypochlorous acid: reactants consumption and byproducts formation
International audienc
Hyphenated LC-MS / LTQ-Orbitrap analysis for cyanotoxin chlorination by-products identification and monitoring
International audienc
Chlorination of the cyanotoxin microcystin-LR: Reactants consumption and by-products identification
International audienc