Molecular and cellular determinants of skeletal muscle atrophy and hypertrophy.
The maintenance of adult skeletal muscle mass is ensured by physical exercise. Accordingly, physiological and pathological situations characterized by either impaired motor neuron activity, reduced gravity (microgravity during space flights), or reduced physical activity result in loss of muscle mass. Furthermore, a plethora of clinical conditions, including cancer, sepsis, diabetes, and AIDS, are associated with varying degrees of muscle atrophy. The cellular and molecular pathways responsible for maintaining the skeletal muscle mass are not well defined. Nonetheless, studies aimed at the understanding of the mechanisms underlying either muscular atrophy or hypertrophy have begun to identify the physiological determinants and clarify the molecular pathways responsible for the maintenance of muscle mass.
Sartorelli
Vittorio
V
Muscle Gene Expression Group Laboratory of Muscle Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA. sartorev@mail.nih.gov
Fulco
Marcella
M
D000818:Animals; D006801:Humans; D006984:Hypertrophy / Q000235:genetics*; D018482:Muscle, Skeletal / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D009133:Muscular Atrophy / Q000235:genetics*