title: Improvement in muscular performance and decrease in tumor necrosis factor level in old age after antioxidant treatment.
abstract: Aging-related loss of muscle function is a predictor of mortality and a surrogate parameter of the aging process. Its consequences include a high risk for falls, hip fractures, and loss of autonomy. Aging is associated with changes in the oxidant/antioxidant balance including a decrease in plasma thiol (cysteine) concentration. To assess the importance of cysteine, we determined in a double-blind study the effects of N-acetylcysteine on the functional capacity of frail geriatric patients and their response to physical exercise. The subjects on placebo showed only a relatively weak response, and 31% showed even a decrease in more than one parameter during the observation period. Low plasma arginine levels were correlated with a weak overall performance before exercise and a poor response to exercise. N-Acetylcysteine strongly enhanced the increase in knee extensor strength and significantly increased the sum of all strength parameters if adjusted for baseline arginine level as a confounding parameter. N-acetylcysteine had no significant effect on growth hormone and IGF-1 levels but caused a significant decrease in plasma TNF-alpha. These findings may provide a basis for therapeutic intervention and suggest that the loss of function involves limitations in cysteine and one or more other amino acids which may compromise muscular protein synthesis.
authors.affiliation: Bethanien Krankenhaus, Geriatrisches Zentrum der Universität Heidelberg, Rohrbacher Strasse 149, 69126, Heidelberg, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Hauer
authors.forename: Wulf
authors.initials: W
authors.lastname: Hildebrandt
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Sehl
authors.forename: Lutz
authors.initials: L
authors.lastname: Edler
authors.forename: Peter
authors.initials: P
authors.lastname: Oster
authors.forename: Wulf
authors.initials: W
authors.lastname: Dröge
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology*; D000368:Aged; D000975:Antioxidants / Q000494:pharmacology*; D003071:Cognition / Q000187:drug effects; D015444:Exercise; D006801:Humans; D009132:Muscles / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D014409:Tumor Necrosis Factor-alpha; D000111:Acetylcysteine