Whey proteins promote post prandial positive nitrogen balance in a muscle wasting situation but probably for a too short period of time to translate into muscle sparing

Background and aims: Muscle wasting occurred by an imbalance of muscle protein metabolism. Most of catabolic states are characterized by both an insulin and amino acid resistance which result into a food intake inefficiency to promote positive nitrogen balance during the post prandial period. So far, fast digested proteins (i.e whey) have been shown to be more efficient than casein to promote a stimulation of muscle protein synthesis (PS) in such situations; however, muscle mass is rarely improved. Our hypothesis is that this stimulation occurs only for a short period of time in the fed state, which remains insufficient to induce a significant increase in muscle mass. To address this point, a PS and proteolysis (PRO) kinetic study at the muscle level is required.Methods: Adult mini pigs were catheterized into both the femoral artery and vein and infused with 13C Phe to assess continuously) muscle PS and PRO in the hindlimb by the substrate and tracer arterio-venous difference method (every 30min before (PA) and after food intake). The catabolic state was induced by glucocorticoid treatment (8d); both casein and whey effects on PS and PRO were tested over time for 6.5 h.Results: After glucocorticoids, animals were in negative nitrogen balance at PA and casein intake had no effect on both PS and PRO and animals remained in negative nitrogen balance during the whole postprandial period. With whey, treated animals are able to generate a positive nitrogen balance for 120min after food intake (PS:+40% and PRO:-20%) which decreased thereafter along the postprandial period. Glucocorticoids were associated with insulin resistance (postprandial period: increased insulin/glycaemia). When fed whey, animals still presented hyperinsulinemia but normalized postprandial glycaemia.Conclusions. Whey are more efficient to generate positive muscle nitrogen balance in catabolic states but it remained only for a short period of time which may limit their efficiency on muscle wasting. Nutritional strategies have to be studied to optimize the duration of whey efficiency in the catabolic states. By contrast, whey are interesting to control post prandial hyperglycaemia in muscle protein wasting situations

En situation de catabolisme musculaire, les protéines de lactosérum permettent bien de restaurer un anabolisme musculaire post prandial mais d’une durée très transitoire probablement insuffisante pour limiter la fonte musculaire

En situation de catabolisme musculaire, les protéines de lactosérum permettent bien de restaurer un anabolisme musculaire post prandial mais d’une durée très transitoire probablement insuffisante pour limiter la fonte musculair

Les intérêts « nutrition-santé » de la fermentation

National audienc

Impact of dietary fibers on metabolic cross talk between the splanchnic area and the muscle/adipose in mini pigs

Hypercaloric diets are one of the causes of the increased obesity prevalence worldwide (and particularly in western countries). Conversely, dietary fibers consumption is associated with a better health status. Yet, dietary fibers consumption in western countries (20 g/d in France or Italy) is below the values of dietary fiber intake recommended by health care organizations (30 g/d). One of the ways to increase fiber intake in populations is to supply fiber-enriched foodstuffs, and particularly food products enriched with fibers capable to improve metabolic health (i.e. fermentable fibers). The aim of our work is to determine if, in overfed minipigs, dietary fermentable fibers supplementation included in a regularly consumed food (i.e. bread), was capable to limit the obesity-linked metabolic disorders induced by overfeeding

Quels effets des métabolites produits lors de la dégradation des fibres par le microbiote ? Focus sur l’insulino-résistance et le stockage des acides gras dans le foie

National audienc

Microbiote intestinal : ces bactéries qui nous veulent du bien

Interview par la journaliste Cécile Couma

Intérêt des aliments fermentés pour la santé

International audienceFermentation allows to preserve food in a sustainable way at a lower cost and contributes to the world food security. This method of preservation is currently very popular with a population in search of naturalness. Health virtues are also attributed to fermented foods because they contain living micro-organisms or specific macro- and micronutrients. Are these products, or the fermentation process, as such really beneficial to health?La fermentation permet de conserver de manière durable les aliments à moindre coût dans de nombreux pays et participe grandement à la sécurité alimentaire mondiale. Ce mode de conservation est actuellement très prisé par une population en recherche de naturalité. Des vertus santé sont également attribuées aux aliments fermentés parce qu’ils contiennent des microorganismes vivants ou des macro-micronutriments spécifiques. Ces produits, très divers, ou le processus de fermentation en tant que tel sont-ils bénéfiques pour la santé

un pain enrichi en fibres pour limiter les effets délétères de la surnutrition

Carte postale mise en place par l'Institut Carnot Qualiment : Pour valorisation des travaux vis à vis des industriels