Grape polyphenols decrease circulating branched chain amino acids in overfed adults

Introduction and aims: Dietary polyphenols have long been associated with health benefits, including the prevention of obesity and related chronic diseases. Overfeeding was shown to rapidly induce weight gain and fat mass, associated with mild insulin resistance in humans, and thus represents a suitable model of the metabolic complications resulting from obesity. We studied the effects of a polyphenol-rich grape extract supplementation on the plasma metabolome during an overfeeding intervention in adults, in two randomized parallel controlled clinical trials. Methods: Blood plasma samples from 40 normal weight to overweight male adults, submitted to a 31-day overfeeding (additional 50% of energy requirement by a high calorie-high fructose diet), given either 2 g/day grape polyphenol extract or a placebo at 0, 15, 21, and 31 days were analyzed (Lyon study). Samples from a similarly designed trial on females (20 subjects) were collected in parallel (Lausanne study). Nuclear magnetic resonance (NMR)-based metabolomics was conducted to characterize metabolome changes induced by overfeeding and associated effects from polyphenol supplementation. The clinical trials are registered under the numbers NCT02145780 and NCT02225457 at ClinicalTrials.gov. Results: Changes in plasma levels of many metabolic markers, including branched chain amino acids (BCAA), ketone bodies and glucose in both placebo as well as upon polyphenol intervention were identified in the Lyon study. Polyphenol supplementation counterbalanced levels of BCAA found to be induced by overfeeding. These results were further corroborated in the Lausanne female study.Conclusion: Administration of grape polyphenol-rich extract over 1 month period was associated with a protective metabolic effect against overfeeding in adults

Filmer les procès, un enjeu social

International audienc

Filmer les procès, un enjeu social

International audienc

Plasma lutein and zeaxanthin and other carotenoids as modifiable risk factors for age-related maculopathy and cataract: the POLA Study.

PURPOSE: To assess the associations of plasma lutein and zeaxanthin and other carotenoids with the risk of age-related maculopathy (ARM) and cataract in the population-based Pathologies Oculaires Li? ?'Age (POLA) Study. METHODS: Retinal photographs were graded according to the international classification. ARM was defined by the presence of late ARM (neovascular ARM, geographic atrophy) and/or soft indistinct drusen (>125 microm) and/or soft distinct drusen (>125 microm) associated with pigmentary abnormalities. Cataract classification was based on a direct standardized lens examination at the slit lamp, according to Lens Opacities Classification System III. Plasma carotenoids were measured by high-performance liquid chromatography (HPLC), in 899 subjects of the cohort. RESULTS: After multivariate adjustment, the highest quintile of plasma zeaxanthin was significantly associated with reduced risk of ARM (OR=0.07; 95% CI: 0.01-0.58; P for trend=0.005), nuclear cataract (OR=0.23; 95% CI: 0.08-0.68; P for trend=0.003) and any cataract (OR=0.53; 95% CI: 0.31-0.89; P for trend=0.01). ARM was significantly associated with combined plasma lutein and zeaxanthin (OR=0.21; 95% CI: 0.05-0.79; P for trend=0.01), and tended to be associated with plasma lutein (OR=0.31; 95% CI: 0.09-1.07; P for trend=0.04), whereas cataract showed no such associations. Among other carotenoids, only beta-carotene showed a significant negative association with nuclear cataract, but not ARM. CONCLUSIONS: These results are strongly suggestive of a protective role of the xanthophylls, in particular zeaxanthin, for the protection against ARM and cataract

Characterization and identification of eight designer benzodiazepine metabolites by incubation with human liver microsomes and analysis by a triple quadrupole mass spectrometer

International audienceDesigner benzodiazepines (DBZDs) have become of particular importance in the past few years. The metabolite monitoring of DBZD in biological fluids could be of great interest in clinical and forensic toxicology. However, DBZD metabolites are not known or not commercially available. The identification of some DBZD metabolites has been mostly explored by self-administration studies or by in vitro studies followed by high-resolution mass spectrometry. The question arose whether a unit resolution instrument could be efficient enough to allow the identification of DBZD metabolites. In this study, we used an in vitro experiment where eight DBZDs (diclazepam, flubromazepam, etizolam, deschloroetizolam, flubromazolam, nifoxipam, meclonazepam and clonazolam) were incubated with human liver microsomes (HLMs) and metabolite identification was carried out by using a UHPLC coupled to a QTRAP triple quadrupole linear iontrap tandem mass spectrometer system. Post-mortem samples obtained from a real poisoning case, involving deschloroetizolam and diclazepam, were also analysed and discussed. Our study using HLM allowed the identification of 26 metabolites of the 8 DBZDs. These were denitro-, mono- or di-hydroxylated and desmethyl metabolites. In the forensic case, diclazepam was not detected whereas its metabolites (lormetazepam and lorazepam) were present at high concentrations in urine. We also identified hydroxy-deschloroetizolam in urine, while the parent compound was not detected in this matrix. This supports the approach that LC coupled to a simple QTRAP could be used by laboratories to identify other not-known/not-commercialized new psychoactive substance (NPS) metabolites

Performance and Suitability of Mindray BS480©: A Fully Open Clinical Chemistry Analyzer.

International audienceMindray BS480©, a multi-parametric and random-access clinical chemistry instrument, is suitable for medium-sized hospital applications. Large laboratories in hospital environments require high throughput non-emergency settings that could slow routine production lines. In addition, the possibility to adapt to different methodologies is of great convenience for improving the transfer from manual to automated applications. The aim of the study is to evaluate analytical performances and to draw a comparison between analyzers for most common clinical parameters under simulated routine conditions

Carbon monoxide exposure enhances arrhythmia after cardiac stress: involvement of oxidative stress

International audienceArrhythmias following cardiac stress are a key predictor of death in healthy population. Carbon monoxide (CO) is a ubiquitous pollutant promoting oxidative stress and associated with hospitalization for cardiovascular disease and cardiac mortality. We investigated the effect of chronic CO exposure on the occurrence of arrhythmic events after a cardiac stress test and the possible involvement of related oxidative stress. Wistar rats exposed chronically (4 weeks) to sustained urban CO pollution presented more arrhythmic events than controls during recovery after cardiac challenge with isoprenaline in vivo. Sudden death occurred in 22% of CO-exposed rats versus 0% for controls. Malondialdehyde (MDA), an end-product of lipid peroxidation, was increased in left ventricular tissue of CO-exposed rats. Cardiomyocytes isolated from CO-exposed rats showed higher reactive oxygen species (ROS) production (measured with MitoSox Red dye), higher diastolic Ca 2? resulting from SR calcium leak and an higher occurrence of irregular Ca 2? transients (measured with Indo-1) in comparison to control cells after a high pacing sequence. Acute treatment with a ROS scavenger (N-acetylcysteine, 20 mmol/L, 1 h) prevented this sequence of alterations and decreased the number of arrhythmic cells following high pacing. Chronic CO exposure promotes oxidative stress that alters Ca 2? homeostasis (through RYR2 and SERCA defects) and thereby mediates the triggering of ventricular arrhythmia after cardiac stress that can lead to sudden death

Biopolitique, éthique et subjectivation, questions de modernité

Du 24 au 28 juin 2009, s’est tenue une université d’été internationale sur le campus de l’université nationale (publique) Chiao Tung, à Hsin Chu, une ville de 500 000 habitants, au sud-ouest de Taipeh, et où sont implantées plusieurs universités réputées. La « puissance invitante » à l’initiative de cette université d’été était « The Graduate Institute for Social Research and Cultural Studies », un département et centre de recherche de l’université Chiao-Tung. L’université Paris 8 et l’université de Porto étaient partenaires de cette initiative. Le thème de ce rassemblement, proposé par nos collègues taiwanais, était le suivant : « Biopolitics, Ethics and Subjectivation – Questions on Modernity » >> lire la suit

Philosophie et cinéma

Le comité de rédaction de la revue Appareil a décidé de regrouper dans ce nouveau numéro un certain nombre de textes déjà publiés sous la rubrique « Varia » s’inscrivant à la croisée des chemins entre philosophie et cinéma. Si quelques-uns de ces articles ont été remaniés à cette occasion par les auteurs, d’autres sont restés inchangés, d’autres encore y ont trouvé leur place pour une première publication. Le champ d’exploration de ce numéro est donc très vaste. Il s’y dessine néanmoins une préoccupation commune, à savoir la mise en évidence du lien étroit entre vérité d’une époque et technique dès lors qu’elle fait appareil. Or, le cinéma fait précisément appareil tel que nous le définissons dans le cadre de la revue comme J.-L. Déotte et D. Payot l’ont précisé dans À propos d’appareil pour sa présentation. >> lire la suit