Aging influences the expression of early response genes following acute resistance exercise in trained skeletal muscle

Abstract

To identify the influence of age on skeletal muscle transcriptional responses to resistance exercise (RE), we recruited 14 young (<40 y) and 8 older (>;60 y) participants. They underwent 12‐week unilateral arm RE training, and conducted one bout of acute RE one week later. Biceps brachii muscle biopsies were obtained 4h and 24h post exercise (PE). Gene expression was assessed using Affymetrix U133A microarrays, and analyzed using an intensity‐based Bayesian moderated paired t‐test. The immediate‐early response genes FOS, EGR1, JUNB, and NR4A3, and other key genes for muscle metabolism including IL6R, PRKAG2, EIF2AK3, HEY1, and ANKRD1, showed striking differences between young and old muscle. They were dramatically up‐regulated PE in the young, but highly down‐regulated in the old (Table 1). This age effect might implicate the diminished metabolic and hypertrophic benefits of RE with aging.Funding for this study was provided by NIH RO1 NS40606–01