[Regulatory role of miR-205-5p in the proliferation, differentiation and muscle atrophy of C2C12 myoblasts].

The growth and development of skeletal muscle are closely associated with the proliferation, differentiation, and fusion of myoblasts. MicroRNAs (miRNAs) are a class of non-coding RNAs approximately 22 nucleotides in length that regulate skeletal muscle formation. miR-205-5p has been implicated in various physiological processes and diseases; however, its role in muscle development remains unclear. Therefore, this study used C2C12 myoblasts as a model to investigate the regulatory effects of miR-205-5p on myoblast proliferation, differentiation, and muscle atrophy, and to preliminarily elucidate its role in maintaining skeletal muscle homeostasis. The results showed that overexpression of miR-205-5p significantly inhibited the proliferation of C2C12 myoblasts while promoting their differentiation (P0.05), whereas interference with miR-205-5p yielded opposite results. In both the muscle atrophy model established after 8 days of induced differentiation and the dexamethasone-induced muscle atrophy model, overexpression of miR-205-5p alleviated the occurrence of muscle atrophy, whereas suppression of miR-205-5p expression exacerbated muscle atrophy (P0.05). In conclusion, miR-205-5p contributes to the maintenance of skeletal muscle homeostasis during muscle development by inhibiting proliferation, promoting differentiation, and attenuating muscle atrophy. This study provides a new molecular basis for elucidating the regulatory mechanisms of microRNAs in muscle development and for muscle atrophy intervention research.