Efeito da suplementação oral crônica com L-glutamina e L-alanina livres ou como dipeptídeo sobre o estresse oxidativo e HSP27 em ratos submetidos a exercícios resistido

Abstract

Introduction: Athletic Resistance exercise way promotes chronic oxidative stress, which implies in exacerbated immune inflammatory response with consequent reduction in performance and health effects. At the same time, intense exercise improves consumption of glutamine for cells and tissues, thereby reducing the availability of this amino acid to the body. However, studies evaluating the glutamine metabolism in resistance exercise are still scarce. The synthesis of antioxidants such as glutathione (GSH) and cytoprotective proteins such as heat shock proteins (HSPs) can be influenced by the availability of glutamine. Objective: To evaluate the effect of chronic oral supplementation with L-glutamine and L-alanine, both in its free form or as dipeptide on oxidative stress and the cytoprotection mediated by HSP 27 in rats subjected to resistance exercise. Methods: Fifty (n = 10 per group) Wistar adult rats were divided into 5 groups: Sedentary (SED), Trained (CTRL) and supplemented with DIP, solution with L-glutamine and free L-alanine (GLN + ALA) and L-alanine (ALA). The trained groups were underwent to climb stairs protocol for six weeks. Supplementations were offered in 4% solution in drinking water in the last 21 days of the experiment. Were analyzed: maximum load test, blood lactate, glutamine and glutamate (in plasma, liver and muscle Tibialis and EDL), creatine kinase and myoglobin (plasma), transaminase (plasma), oxidized (GSSG) and reduced (GSH) glutathione (erythrocytes, liver and muscle-Tibialis and EDL), TBARS (liver and muscle Tibialis-and EDL), HSP-27 and Glutamine Synthetase expression (Tibialis muscle). Results: The results showed that resistance exercise protocol reduced glutamine concentration in muscle (p <0.05) increased the ratio [GSSG / GSH] in the liver, erythrocytes and muscle (p <0.05), and TBARS increase the tissue. The Supplementation with L-glutamine and L-alanine and free dipeptide and increased glutamine concentrations in the plasma and tissues (p <0.05), improved the ratio of [GSSG / GSH] in liver, erythrocytes and muscle (p <0.05). HSP 27 expression was also increased in Tibialis Muscle. There was reduction of TBARS in tissues and creatine kinase in plasma (p <0.05). Conclusion: Supplementations with L-glutamine and L-alanine in its free form or as dipeptide increase the synthesis of GSH and Expression HSP 27, thus reducing oxidative stress caused by resistance exercise.