Molecular basis of the myogenic profile of aged human skeletal muscle satellite cells during differentiation

Tiziana Pietrangelo , Cristina Puglielli , Rosa Mancinelli , Sara Beccafico , Giorgio Fanò , Stefania Fulle

is the age-related loss of muscle mass, strength and function. Human muscle proteins are synthesized at a slower rate in the elderly than in young adults, leading to atrophy and muscle mass loss with a decline in the functional capability. Additionally, aging is accompanied by a decrease in the ability of muscle tissue to regenerate following injury or overuse due to the impairment of intervening satellite cells, in which we previously reported oxidative damage evidences. The aim of the present study was to determine the effects of aging on myoblasts and myotubes obtained from human skeletal muscle, and characterize the transcriptional profile as molecular expression patterns in relation to age-dependent modifications in their regenerative capacity. Our data show that the failure to differentiate does not depend on reduced myogenic cell number, but difficulty to complete the differentiation program. Data reported here suggested the following findings: i) oxidative damage accumulation in molecular substrates, probably due to impaired antioxidant activity and insufficient repair capability, ii) limited capability of elderly myoblasts to execute a complete differentiation program; restricted fusion, possibly due to altered cytoskeleton turnover and extracellular matrix degradation, and iii) activation of atrophy mechanism by activation of a specific FOXO-dependent program.

Mots clés: satellite cells

Tiziana Pietrangelo, Cristina Puglielli, Rosa Mancinelli, Sara Beccafico, Giorgio Fanò, et al.. Molecular basis of the myogenic profile of aged human skeletal muscle satellite cells during differentiation. Experimental Gerontology, 2009, 44 (8), pp.523. ⟨10.1016/j.exger.2009.05.002⟩. ⟨hal-00504929⟩