Control of muscle mass during growth and aging: Clinical targets and pathways

Muscle mass is a strong indicator of overall health in older adults. In healthy individuals, an adequate muscle mass is maintained through a balance between anabolic pathways, such as the mTOR pathway (mammalian target of rapamycin), and catabolic pathways, including the myostatin signaling. With aging, hormonal decline, insulin resistance, mitochondrial dysfunction, and lifestyle factors contribute to the development of anabolic resistance. Thus, the regulation of muscle protein synthesis becomes less efficient in older adults. Diagnostic parameters for sarcopenia are highly useful in this population as they enable proper assessment of muscle mass, muscle strength and physical performance. Appropriate management of sarcopenia relies on a multimodal approach that combines physical exercise, tailored nutritional strategies, and potential pharmacological intervention, representing a key strategy for preserving muscle mass, functional capacity, and quality of life in older adults.