Regulatory roles of microRNAs in sarcopenia and exercise intervention / 生理学报

Sarcopenia is an age-related degenerative disease, in which skeletal muscle mass and function are reduced during aging process. Physical intervention is one of the most effective strategies available for the treatment of sarcopenia. Studies have shown that microRNAs (miRNAs), as important regulators of gene expression, play an important role in maintaining the homeostasis of senescent skeletal muscle cells by regulating skeletal muscle cell development (proliferation and differentiation), mitochondrial biogenesis, protein synthesis and degradation, inflammatory response and metabolic pathways. Furthermore, exercise can combat age-related changes in muscle mass, composition and function, which is associated with the changes in the expression and biological functions of miRNAs in skeletal muscle cells. In this article, we systematically review the regulatory mechanisms of miRNAs in skeletal muscle aging, and discuss the regulatory roles and molecular targets of exercise-mediated miRNAs in muscular atrophy during aging process, which may provide novel insights into the prevention and treatment of sarcopenia.

Regulatory Role of Exercise-induced Autophagy in Rehabilitation of Sarcopenia (review) / 中国康复理论与实践

Sarcopenia is an aging-related disease with a significant reduction in mass and strength of skeletal muscle due to the imbalance between protein synthesis and degradation. Autophagy acts as a conserved mechanism regulating the balance of protein metabolism in body and can be regulated by multiple signaling pathways such as AMP-activated protein kinase (AMPK), insulin like growth factor (IGF)/ protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) and phosphatidylinositol 3 kinase (PI3K)/Akt/mTOR induced by exercise. Exercise-activated autophagy regulates skeletal muscle remodeling and homeostasis under different physiological and pathological conditions, which is the key to skeletal muscle health maintenance. This article reviewed the regulator roles and potential molecular mechanisms of varying exercise-induced autophagy in the prevention, treatment and rehabilitation of sarcopenia.