Role of Exercise in Skeletal Muscle Atrophy: A Mechanistic Investigation

Abstract

PURPOSE Skeletal muscle atrophy induces overall health problems and many related diseases in older adults. In particular, sarcopenia is related to lowered quality of life, decreased physical activity, high levels of morbidity and mortality owing to chronic diseases, and even falling. Despite the many clinical studies on skeletal muscle atrophy, a little study had been about the exact mechanism of skeletal muscle atrophy at the molecular level. In 2017, A disease code (ICD-10-CM) for skeletal muscle atrophy related to sarcopenia was announced to attempt a clinical approach in the United States. According to these approaches, non-invasive clinical treatment is the most effective method for treating skeletal muscle atrophy. The purpose of this study was to analyze the molecular mechanisms of muscular exercise and related skeletal muscle atrophy factors. METHODS This systemic review focused on skeletal muscle atrophy and muscular exercise. The keywords were used on “MeSH: muscle atrophy OR skeletal muscle atrophy OR muscle OR atrophy AND physical exercise OR exercise OR exercise training” for English and Korean. This paper searched PubMED, OVIDMEDLINE, and EMBASE for literature consideration. RESULTS Skeletal muscle atrophy was related to a complex molecular network, and exercise affects IGF-1/Akt/mTOR signaling. The related skeletal muscle atrophy factors were evaluated as MurF1, MAFbx, IGF-1, and NFkB. We proposed new related factors such as ATF 4, Gadd45a, and p21; however, the results related to exercise were not shown in recent studies. CONCLUSIONS In conclusion, we identified skeletal muscle atrophy factors at the molecular level of muscle physiology, and these new factors may become an interesting field of study in clinical human trial and animal studies.

Keywords

• exercise
• skeletal muscle atrophy
• sarcopenia
• aging