[Role of mechanosensitive ion channels in skeletal muscle regeneration]

Skeletal muscle is composed of thousands of myofibers that enable contraction and relaxation. Myofibers are constantly exposed to biophysical stresses during repeated contractile processes; nevertheless, skeletal muscle maintains its "resilience" through both structural robustness and the ability to sense and adapt to biophysical forces. Regulation of intra- and extracellular ionic concentrations is a critical determinant for cell growth, fate determination, and death. In myofibers, Ca²⁺ release from sarcoplasmic reticulum is well established as the trigger for myofiber contraction, whereas accumulating evidence suggests the importance of Ca²⁺ influx across sarcolemma in myofiber homeostasis. Moreover, other ions such as magnesium ion are increasingly recognized for their roles in skeletal muscle functions. In this review, we summarize the current understandings of adaptive mechanisms dependent on Ca²⁺ influx in response to biophysical stresses, with a particular focus on membrane repair and myofiber regeneration processes.