Antioxidant Supplementation Restores Defective Leucine Stimulation of Protein Synthesis in Skeletal Muscle from Old Rats

Aging is characterized by a progressive loss of muscle mass that could be partly explained by a defect in the anabolic effect of food intake. We previously reported that this defect resulted from a decrease in the protein synthesis response to leucine in muscles from old rats. Because aging is assoc...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of nutrition 2008-11, Vol.138 (11), p.2205-2211
Main Authors: Marzani, Barbara, Balage, Michèle, Vénien, Annie, Astruc, Thierry, Papet, Isabelle, Dardevet, Dominique, Mosoni, Laurent
Format: Article
Language:English
Subjects:
Aging - physiology
animal models
Animals
antioxidants
Antioxidants - pharmacology
Biological and medical sciences
Biomarkers
Dietary Supplements
Feeding. Feeding behavior
Food and Nutrition
Fundamental and applied biological sciences. Psychology
inflammation
Inflammation - metabolism
leucine
Leucine - metabolism
Life Sciences
muscle physiology
Muscle Proteins - biosynthesis
Muscle, Skeletal - drug effects
Muscle, Skeletal - metabolism
old animals
Oxidative Stress - physiology
protein metabolism
protein synthesis
Rats
Rats, Wistar
Ribosomal Protein S6 Kinases - metabolism
sarcopenia
senescence
skeletal muscle
Striated muscle. Tendons
Vertebrates: anatomy and physiology, studies on body, several organs or systems
Vertebrates: osteoarticular system, musculoskeletal system
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Aging is characterized by a progressive loss of muscle mass that could be partly explained by a defect in the anabolic effect of food intake. We previously reported that this defect resulted from a decrease in the protein synthesis response to leucine in muscles from old rats. Because aging is associated with changes in oxidative status, we hypothesized that reactive oxygen species-induced oxidative damage may be involved in the impairment of the anabolic effect of leucine with age. The present study assessed the effect of antioxidant supplementation on leucine-regulated protein metabolism in muscles from adult and old rats. Four groups of 8- and 20-mo-old male rats were supplemented or not for 7 wk with an antioxidant mixture containing rutin, vitamin E, vitamin A, zinc, and selenium. At the end of supplementation, muscle protein metabolism was examined in vitro using epitrochlearis muscles incubated with increasing leucine concentrations. In old rats, the ability of leucine to stimulate muscle protein synthesis was significantly decreased compared with adults. This defect was reversed when old rats were supplemented with antioxidants. It was not related to increased oxidative damage to 70-kDa ribosomal protein S6 kinase that is involved in amino acid signaling. These effects could be mediated through a reduction in the inflammatory state, which decreased with antioxidant supplementation. Antioxidant supplementation could benefit muscle protein metabolism during aging, but further studies are needed to determine the mechanism involved and to establish if it could be a useful nutritional tool to slow down sarcopenia with longer supplementation.
ISSN:0022-3166
1541-6100
DOI:10.3945/jn.108.094029