title: Vitamin C supplementation affects oxidative-stress blood markers in response to a 30-minute run at 75% VO2max.
abstract: Vitamin C supplementation (VC) (either 500 or 1000 mg/d for 2 wk) was compared to a placebo treatment (P) to ascertain if VC could influence oxidative stress. Twelve healthy males (25 +/- 1.4 y) were randomly assigned in a counter-balanced design with a 2-wk period between treatments. Data were analyzed using repeated measures ANOVA. Exercise intensity measures (VO(2), RER, RPE, HR, lactate) were similar across treatments. Resting blood oxidative-stress markers were unaffected by treatment. Exercise decreased total blood glutathione (TGSH) and reduced glutathione (GSH) and increased oxidized glutathione (GSSG) (P < 0.01) independent of treatment. Protein carbonyls (PC) increased 3.8 fold in the P (P < 0.01). VC attenuated the PC exercise response in a dose-dependent manner ( P < 0.01). Thiobarbituric acid reactive substances (TBARS) was not influenced by exercise (P = 0.68) or VC. These data suggest that VC supplementation can attenuate exercise-induced protein oxidation in a dose-dependent manner with no effect on lipid peroxidation and glutathione status.
authors.affiliation: Exercise and Sport Science Dept, University of North Carolina, Greensboro, NC, 27402-6169, USA.
authors.forename: Allan H
authors.initials: AH
authors.lastname: Goldfarb
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Patrick
authors.forename: Scott
authors.initials: S
authors.lastname: Bryer
authors.forename: Tongjian
authors.initials: T
authors.lastname: You
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000975:Antioxidants / Q000008:administration & dosage* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000097:blood / Q000187:drug effects; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects / Q000502:physiology; D008297:Male; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010101:Oxygen Consumption; D012420:Running / Q000502:physiology*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017392:Thiobarbituric Acid Reactive Substances; D005978:Glutathione; D001205:Ascorbic Acid