title: Antioxidant response to oxidative stress induced by exhaustive exercise.
abstract: The aim of this work was to demonstrate the occurrence of oxidative stress during exhaustive exercise and to determine the antioxidant response. Eight voluntary male subjects participated in this study. The exercise was a cycling mountain stage (171 km) and the cyclists took a mean+/-S.E.M. time of 270+/-12 min to complete it. Blood samples were taken before the cycling stage, immediately after the stage, 3 h after finishing the stage and on the morning of the following day. We determined the activities of erythrocyte antioxidant enzymes, blood levels of oxidised glutathione, plasma levels of antioxidant vitamins and carotenoids, and the serum lipid and cholesterol profile. The mountain cycling stage induced significant increases in catalase and glutathione reductase activities. Significant decreases in glutathione peroxidase activity, both determined with hydrogen peroxide and with cumene hydroperoxide as substrates, were observed. Blood oxidised glutathione and serum uric acid rose after the stage. Plasma vitamin E increased after the stage but dropped to below basal values after 3 h of recovery. Triglycerides and VLDL-cholesterol increased significantly after the stage and remained high 3 h after the cycling stage. The mountain cycling stage induced oxidative stress, as was evidenced by the increases in blood GSSG and in serum urate concentrations and by the pattern of change of erythrocyte antioxidant enzyme activities. A specific utilisation of alpha-tocopherol against oxidative stress during recovery was evidenced.
authors.affiliation: Laboratori de Ciències de l'Activitat Física and Department de Biologia Fonamental i Ciències de la Salut, Edifici Guillem Colom, Facultat de Ciències, Universitat de les Illes Balears, Palma de Mallorca, Balears, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Aguiló
authors.forename: Pedro
authors.initials: P
authors.lastname: Tauler
authors.forename: Emilia
authors.initials: E
authors.lastname: Fuentespina
authors.forename: Josep A
authors.initials: JA
authors.lastname: Tur
authors.forename: Alfredo
authors.initials: A
authors.lastname: Córdova
authors.forename: Antoni
authors.initials: A
authors.lastname: Pons
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000975:Antioxidants / Q000032:analysis*; D002338:Carotenoids / Q000097:blood; D002784:Cholesterol / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D015444:Exercise / Q000502:physiology*; D019803:Glutathione Disulfide / Q000097:blood*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D013997:Time Factors; D014527:Uric Acid / Q000097:blood; D014815:Vitamins / Q000097:blood
chemical_list: D000975:Antioxidants; D008055:Lipids; D014815:Vitamins; D014527:Uric Acid; D002338:Carotenoids; D002784:Cholesterol; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D019803:Glutathione Disulfide