title: Effect of acute and chronic insulin administrations on major factors involved in the control of muscle protein turnover in rainbow trout (Oncorhynchus mykiss).
abstract: In this study, the effect of acute and chronic insulin treatments on major factors involved in the control of muscle protein turnover were investigated in rainbow trout (Oncorhynchus mykiss). We found that acute but not chronic insulin administration leads to the induction of the phosphorylation of several key factors (IRS1, TOR and 4E-BP1) involved in the control of the protein synthesis and to the concomitant down-regulation of the expression of ubiquitin-proteasome-related genes (atrogin1, C2, C9) and the calpains inhibitor calpastatin. In contrast, no modification of autophagy-related gene (LC3B, gabarpl1, atg4b) expressions was observed suggesting that the mechanisms controlling this proteolytic route have diverged throughout the evolution. Overall, these results provide a possible explanation of the growth-promoting properties of insulin previously described in fish and indicate that this hormone acutely administrated is able to exert a regulatory influence on various factors associated with growth in skeletal muscle.
authors.affiliation: INRA, UR1067 Nutrition Métabolisme et Aquaculture, Saint-Pée-sur-Nivelle, France. seiliez@st-pee.inra.fr
authors.forename: Iban
authors.initials: I
authors.lastname: Seiliez
authors.forename: Stéphane
authors.initials: S
authors.lastname: Panserat
authors.forename: Sandrine
authors.initials: S
authors.lastname: Skiba-Cassy
authors.forename: Sergio
authors.initials: S
authors.lastname: Polakof
mesh_terms: D000818:Animals; D029941:Fish Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D007328:Insulin / Q000494:pharmacology*; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000254:growth & development / Q000378:metabolism; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D010766:Phosphorylation; D014176:Protein Biosynthesis / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D029941:Fish Proteins; D007328:Insulin; D009124:Muscle Proteins