Supplementation with vitamin A enhances oxidative stress in the lungs of rats submitted to aerobic exercise

• Published in: Applied physiology, nutrition, and metabolism nutrition, and metabolism, 2015-12, Vol.40 (12), p.1253-1261
• Main Authors: Gasparotto, Juciano, Petiz, Lyvia Lintzmaier, Girardi, Carolina Saibro, Bortolin, Rafael Calixto, de Vargas, Amanda Rodrigues, Henkin, Bernardo Saldanha, Chaves, Paloma Rodrigues, Roncato, Sabrina, Matté, Cristiane, Zanotto-Filho, Alfeu, Moreira, José Cláudio Fonseca, Gelain, Daniel Pens
• Format: Article
• Language: English
• Subjects: aerobic exercise; Animals; Causes of; cytokines; Dietary supplements; Dietary Supplements - toxicity; exercice aérobie; Exercise; Glutathione Peroxidase - metabolism; Health aspects; Inflammation Mediators - metabolism; Interleukin-10 - metabolism; Lipid Peroxidation - drug effects; lung; Lung - drug effects; Lung - metabolism; Lungs; Male; Oxidants - toxicity; Oxidative stress; Oxidative Stress - drug effects; Physical Exertion; poumon; Protein Carbonylation - drug effects; Rats, Wistar; Reactive Oxygen Species - metabolism; Receptor for Advanced Glycation End Products - metabolism; Rodents; stress oxydatif; Superoxide Dismutase - metabolism; Swimming; Time Factors; Tumor Necrosis Factor-alpha - metabolism; Vitamin A; Vitamin A - toxicity; vitamine A
• ISSN: 1715-5312; 1715-5320
• DOI: 10.1139/apnm-2015-0218

Exercise training induces reactive oxygen species production and low levels of oxidative damage, which are required for induction of antioxidant defenses and tissue adaptation. This process is physiological and essential to improve physical conditioning and performance. During exercise, endogenous antioxidants are recruited to prevent excessive oxidative stress, demanding appropriate intake of antioxidants from diet or supplements; in this context, the search for vitamin supplements that enhance the antioxidant defenses and improve exercise performance has been continuously increasing. On the other hand, excess of antioxidants may hinder the pro-oxidant signals necessary for this process of adaptation. The aim of this study was to investigate the effects of vitamin A supplementation (2000 IU/kg, oral) upon oxidative stress and parameters of pro-inflammatory signaling in lungs of rats submitted to aerobic exercise (swimming protocol). When combined with exercise, vitamin A inhibited biochemical parameters of adaptation/conditioning by attenuating exercise-induced antioxidant enzymes (superoxide dismutase and glutathione peroxidase) and decreasing the content of the receptor for advanced glycation end-products. Increased oxidative damage to proteins (carbonylation) and lipids (lipoperoxidation) was also observed in these animals. In sedentary animals, vitamin A decreased superoxide dismutase and increased lipoperoxidation. Vitamin A also enhanced the levels of tumor necrosis factor alpha and decreased interleukin-10, effects partially reversed by aerobic training. Taken together, the results presented herein point to negative effects associated with vitamin A supplementation at the specific dose here used upon oxidative stress and pro-inflammatory cytokines in lung tissues of rats submitted to aerobic exercise.