The maintenance of skeletal muscle mass and metabolic capacity is extremely important for human health and quality of life (Wolfe RR 2006). Skeletal muscle has distinct metabolic and contractile properties that can be influenced by nutrients uptake, microenvironment, and contractile activity. Plasticity and heterogeneity have also been shown to be hallmarks of skeletal muscle as shown by muscle morphology, fiber type, and oxidative capacity. Age, disuse, fasting and various degenerative diseases alter skeletal muscle mass and function. In elderly patients, sarcopenia and failure of basal autophagy (García-Prat L, et al. 2016) is leading to muscle loss, whilst in neurodegenerative diseases the loss of neuromuscular junctions leads to muscle atrophy and even to death (Walston JD. 2012, Goljanek-Whysall K et al. 2016). In addition, the application of radiation to skeletal muscle has also been shown to alter the response to overload and impair regenerative processes (Gulati AK. 1987, Rosenblatt JD et al. 1992, Rosenblatt JD et al. 1994), even though due to the post-mitotic state of myofibers, it’s often mistakenly said that skeletal muscle is the most radiation resistant tissue in the body (Lewis RB. 1954, Khan MY. 1974).
