Muscle Biomarkers as Molecular Signatures for Early Detection and Monitoring of Muscle Health in Aging.

Maintaining muscle health is essential for preserving mobility, independence, and quality of life with age. As muscle mass and function decline, the risk of frailty, chronic disease, and disability increases. Sarcopenia, characterized by the progressive loss of muscle mass, strength, and function, is a major contributor to these adverse outcomes in older adults. Early identification and monitoring of sarcopenia are critical for timely intervention to prevent irreversible decline. Muscle biomarkers offer a promising approach for detecting muscle deterioration and guiding treatment strategies. This review explores key biomarkers-including insulin-like growth factor 1 (IGF-1), myostatin, interleukin-6 (IL-6), irisin, interleukin 15 (IL-15), and procollagen type III N-terminal propeptide (P3NP)-that reflect underlying processes such as muscle anabolism, inflammation, metabolism, and remodeling. Alterations in these markers are associated with muscle health status. Furthermore, hormonal status, biological sex, and nutritional factors all modulate biomarker levels, emphasizing the need for personalized assessments. Integrating biomarker analysis into clinical practice has the potential to enhance early diagnosis, inform personalized interventions, and ultimately promote healthy aging by maintaining muscle function and reducing disability risk.