Sex differences in muscle health in simulated micro- and partial-gravity environments in rats.

Plant Biology & Bioregenerative Systems

influence, gonadectomy, muscle, health, micro, partial, gravity, environments, rats, muscle, loss, study, examining, influence, gonadectomy, health, micro, skeletal, atrophy, muscle, fibers, study, examining, influence, gonadectomy, health, micro, microgravity, causes

influence, gonadectomy, muscle, health, micro, partial, gravity, environments, rats

muscle, fibers, study, examining, influence, gonadectomy, health, micro, microgravity, causes

muscle, loss, study, examining, influence, gonadectomy, health, micro, skeletal, atrophy

Study examining influence of gonadectomy on muscle health in micro-. Microgravity causes rapid skeletal muscle atrophy, particularly affecting slow-twitch fibers. Protein synthesis decreases while breakdown increases, and muscle phenotype shifts toward faster fibers. Despite exercise countermeasures, significant muscle loss occurs, along with mitochondrial dysfunction and reduced oxidative capacity.

Study examining influence of gonadectomy on muscle health in micro-. Skeletal muscle atrophy progressed rapidly in microgravity with 10-20% mass loss within first month. Type I slow-twitch fibers were preferentially affected. Protein synthesis decreased while proteolytic pathways upregulated. Myosin heavy chain isoforms shifted toward faster phenotypes. Exercise countermeasures attenuated but did not prevent muscle loss. Mitochondrial function declined with reduced oxidative capacity.