Differences in Muscle Protein Synthesis and Anabolic Signaling in the Postabsorptive State and in Response to Food in 65–80 Year Old Men and Women
Year: 2008
Type: article
Abstract: Women have less muscle than men but lose it more slowly during aging. To discover potential underlying mechanism(s) for this we evaluated the muscle protein synthesis process in postabsorptive conditions and during feeding in twenty-nine 65-80 year old men (n = 13) and women (n = 16). We discovered that the basal concentration of phosphorylated eEF2(Thr56) was approximately 40% less (P<0.05) and the basal rate of MPS was approximately 30% greater (P = 0.02) in women than in men; the basal concentrations of muscle phosphorylated Akt(Thr308), p70s6k(Thr389), eIF4E(Ser209), and eIF4E-BP1(Thr37/46) were not different between the sexes. Feeding increased (P<0.05) Akt(Thr308) and p70s6k(Thr389) phosphorylation to the same extent in men and women but increased (P<0.05) the phosphorylation of eIF4E(Ser209) and eIF4E-BP1(Thr37/46) in men only. Accordingly, feeding increased MPS in men (P<0.01) but not in women. The postabsorptive muscle mRNA concentrations for myoD and myostatin were not different between sexes; feeding doubled myoD mRNA (P<0.05) and halved that of myostatin (P<0.05) in both sexes. Thus, there is sexual dimorphism in MPS and its control in older adults; a greater basal rate of MPS, operating over most of the day may partially explain the slower loss of muscle in older women.
Source: PLoS ONE
Institutions: Washington University in St. Louis, University of Nottingham
Language: English
Subfield: Nutrition and Dietetics
Field: Nursing
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,382
Funders: Research Councils UK, European Commission, University of Nottingham, National Institutes of Health, Directorate for Biological Sciences, Biotechnology and Biological Sciences Research Council, National Institute on Aging, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Center for Research Resources
Awards: G1513729285, G1565341982, G3051445963, A Resource for Biomedical Mass Spectrometry, Effects of sex and adiposity on muscle protein synthesis, G637079156, G785008235, Weight Loss and Exercise in Frail Obese Elderly Subjects, G889535532, G8957907046, G9000071536, G9000108806, Washington University Nutrition Obesity Research Center, GENERAL CLINICAL RESEARCH CENTER
OpenAlex ID: W2169296372