title: Sarcopenia, age, atrophy, and myopathy: Mitochondrial oxidative enzyme activities.
abstract: We studied mitochondrial impairment as a factor in the pathologic equivalent of sarcopenia, muscle fiber atrophy associated with increased age.
  
  
  
  Mitochondrial oxidative enzyme activities and coenzyme Q10 levels were measured in frozen human proximal limb muscles with combined age and atrophy, age alone, atrophy alone, denervation, immune myopathies, and mitochondrial disorders with ophthalmoplegia.
  
  
  
  Sarcopenia (age and atrophy) had reduced mean activities of mitochondrial Complexes I, II, and II+III, with severe reduction of Complex I activity in 54% of patients. Atrophy, and specific denervation atrophy, had similar patterns of changes. Age alone had moderately reduced Complex I activity. Mitochondrial myopathies had mildly lower Complex IV activity. Immune myopathies had unchanged enzyme activities.
  
  
  
  Mitochondrial oxidative enzyme activities, especially Complex I, but also Complexes II and II+III, are reduced in muscles with the pathologic equivalent of sarcopenia. Individually, atrophy and age have different patterns of oxidative enzyme changes. Muscle Nerve 56: 122-128, 2017.
authors.affiliation: Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, Box 8111, Saint Louis, Missouri, 63110, USA.|Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Pestronk
authors.affiliation: Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, Box 8111, Saint Louis, Missouri, 63110, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Keeling
authors.affiliation: Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, Box 8111, Saint Louis, Missouri, 63110, USA.
authors.forename: Rati
authors.initials: R
authors.lastname: Choksi
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D042967:Electron Transport Complex I / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000378:metabolism* / Q000473:pathology; D009135:Muscular Diseases / Q000473:pathology*; D055948:Sarcopenia / Q000473:pathology*
chemical_list: D042967:Electron Transport Complex I
keywords: aging; atrophy; mitochondria; muscle; myopathy; sarcopenia