Regulatory Roles of Exercise⁃regulated Circadian Rhythm in Muscular Atrophy / 中国生物化学与分子生物学报

ABSTRACT

As people age, the population of the elderly increases rapidly. With the change of work and lifestyle, the problems such as reduced physical activity and irregular routine become more serious, which results in the significantly increased incidence of skeletal muscle atrophy, and reduced health status and life quality of elderly. At the same time, the imbalance of diets, the decrease of physical activity, and the fluctuation of hormone levels further aggravate the occurrence of skeletal muscle atrophy, and its pathological mechanisms mainly correlated with chronic inflammation, mitochondrial dysfunction, deficient autophagy, increased apoptosis, impaired muscle satellite cell function, and disrupted circadian rhythm. Skeletal muscles, as the largest peripheral biological clock of the body, can affect the fiber structure, mitochondrial function, and muscle mass of skeletal muscles by regulating the circadian core genes BMAL1 and CLOCK. As an important intervention strategy to improve skeletal muscle masses, exercise can also activate the circadian signal pathway and regulate its phase, thus improving muscle regeneration and muscle strengths and delaying muscle atrophy. Therefore, from the perspective of circadian rhythm, this article summarizes the occurrence of muscular atrophy and the molecular mechanism of potential exercise intervention to provide new ideas for the targeted regulation of the prevention, treatment, and rehabilitation of muscular atrophy.