Journal Article

Slow and fast dietary proteins differently modulate postprandial protein accretion

Laboratoire de recherches de technologie laitière ; Institut National de la Recherche Agronomique (INRA), Dangin, Martial, Vasson, M.P, Gachon, P, Boirie, Yves, Unité de Nutrition Humaine (UNH) ; Institut National de la Recherche Agronomique (INRA)-Université d'Auvergne - Clermont-Ferrand I (UdA)-Clermont Université, Maubois, J.L, Beaufrère, B

1997

Overview

The speed of absorption of dietary amino acids by the gut varies according to the type of ingested dietary protein. This could affect postprandial protein synthesis, breakdown, and deposition. To test this hypothesis, two intrinsically 13C-leucine-labeled milk proteins, casein (CAS) and whey protein (WP), of different physicochemical properties were ingested as one single meal by healthy adults. Postprandial whole body leucine kinetics were assessed by using a dual tracer methodology. WP induced a dramatic but short increase of plasma amino acids. CAS induced a prolonged plateau of moderate hyperaminoacidemia, probably because of a slow gastric emptying. Whole body protein breakdown was inhibited by 34% after CAS ingestion but not after WP ingestion. Postprandial protein synthesis was stimulated by 68% with the WP meal and to a lesser extent (+31%) with the CAS meal. Postprandial whole body leucine oxidation over 7 h was lower with CAS (272 +/- 91 micromoles . kg-1) than with WP (373 +/- 56 micromoles . kg-1). Leucine intake was identical in both meals (380 micromoles . kg-1). Therefore, net leucine balance over the 7 h after the meal was more positive with CAS than with WP (P 0.05, WP vs. CAS). In conclusion, the speed of protein digestion and amino acid absorption from the gut has a major effect on whole body protein anabolism after one single meal. By analogy with carbohydrate metabolism, slow and fast proteins modulate the postprandial metabolic response, a concept to be applied to wasting situations

• Publisher: National Academy of Sciences,CCSD,National Academy of Sciences of the United States of America,National Acad Sciences,The National Academy of Sciences of the USA
• Subject: ABSORCION DIGESTIVA / ABSORPTION DIGESTIVE / ACIDE AMINE / ACIDE AMINE LIBRE / Adult / Amino acid metabolism / AMINO ACIDS / Amino Acids - blood / AMINOACIDOS / AMINOACIDOS LIBRES / ANABOLISM / ANABOLISME / ANABOLISMO / Biological Sciences / blood / BLOOD CHEMISTRY / BLOOD COMPOSITION / CARBON / CARBONE / CARBONO / CASEIN / CASEINA / CASEINE / Caseins / Caseins - metabolism / Cellular Biology / COMPOSICION DE LA SANGRE / COMPOSITION DU SANG / DEGRADACION / DEGRADATION / Dietary protein / Dietary Proteins / Dietary Proteins - metabolism / DIGESTION / DIGESTIVE ABSORPTION / FOOD INTAKE / FREE AMINO ACIDS / GENERO HUMANO / GENRE HUMAIN / Humans / Ingestion / INGESTION DE ALIMENTOS / INSULIN / INSULINA / INSULINE / INTESTINAL ABSORPTION / ISOTOPE LABELING / ISOTOPE RADIOACTIF / Kinetics / LEUCINA / LEUCINE / Leucine - metabolism / Life Sciences / MANKIND / metabolism / METABOLISME DES PROTEINES / METABOLISMO PROTEICO / Milk protein / Milk Proteins / Milk Proteins - metabolism / NONOXIDATIVE LEUCINE DISPOSAL / OXIDACION / OXIDATION / OXYDATION / Postprandial Period / PRISE ALIMENTAIRE (HOMME) / PROTEIN ANABOLISM / protein degradation / protein intake / PROTEIN METABOLISM / PROTEIN SYNTHESIS / PROTEINAS / PROTEINAS DE SUERO DE LECHE / PROTEINE / PROTEINE DE LACTOSERUM / PROTEINS / Proteins - metabolism / RADIOISOTOPES / RADIOISOTOPOS / SINTESIS DE PROTEINAS / STABLE ISOTOPES / SYNTHESE PROTEIQUE / TECHNIQUE DES TRACEURS / TECNICAS DE TRAZADORES / TRACER TECHNIQUES / WHEY PROTEIN / Whey Proteins