サルコペニア予防・治療のための電気刺激ベースの治療技術の進歩

Sarcopenia, an age-related disorder characterized by the progressive loss of skeletal muscle mass and function, has emerged as a major health concern in the aging population. Conventional pharmacological approaches, such as myostatin inhibitors and anabolic agents, have shown limited efficacy and safety, underscoring the need for noninvasive therapeutic alternatives. In this context, electrical stimulation (ES) has recently gained significant attention as a promising electroceutical strategy for restoring muscle structure and function. Through direct activation of skeletal muscle fibers, ES (i) induces hypertrophy, (ii) enhances contractile strength, and (iii) restores metabolic balance. This review summarizes the conceptual framework, current limitations, and emerging trends in ES-based sarcopenia therapy, spanning from in vitro mechanistic studies to in vivo efficacy and clinical applications. In particular, we compare conventional clinical ES modalities, including neuromuscular, functional, pulsed, and microcurrent stimulation (NMES, FES, PES, and MT), with self-powered energy-harvesting systems, discussing their therapeutic mechanisms, clinical outcomes, and technical challenges. These advances collectively highlight ES as an alternative approach linking fundamental muscle physiology with clinical rehabilitation. Understanding recent progress in biomaterials, regenerative medicine, and wearable technologies will further guide the development of personalized, adaptive rehabilitation strategies for age-related muscle degeneration.