Treinamento aeróbio de natação aumenta a atividade de enzimas antioxidantes e o conteúdo de glicogênio no músculo esquelético de ratos

Abstract

The present study verified the effects of aerobic swimming training (AST) on biomarkers of oxidative stress, glycogen content and cell growth in the skeletal muscle of rats. Eighteen male Wistar rats (60 days) were divided into two groups: Sedentary Group (GS; n=10): sedentary rats; and Trained Group (GT; n=8): rats subjected to AST (5.0% of body weight), 1h/day, 5x/week, during 8 weeks. The activity of antioxidant enzymes (AOE) superoxide dismutase (SOD [U/ml]), catalase (CAT [µmol/min.mg protein]), glutathione peroxidase (GPx [nmol/min/100mg]), and substances that react with thiobarbituric acid levels (TBARs [nmol MDA/mg protein]) were determined in the right gastrocnemius muscle. Glycogen (mg/100mg), protein (g/100g), and DNA (g/100g) contents were evaluated in the left gastrocnemius muscle. The Mann-Whitney test was used to detect differences between the means. AOE activity was higher in the GT group (CAT: 0.87±0.04; SOD: 6.49±0.45; GPX: 6.49±0.52) when compared to GS group (CAT: 0.52±0.03; SOD: 4.10±0.37; GPx: 2.87±0.35). TBARs levels was lower in GT (GS: 8.90 ± 0.47; GT: 2.35±0.45;). Gastrocnemius glycogen content (GS: 0.108±0.013; GT: 0.320±0.012) and protein/DNA ratio (GS: 24.94±3.25; GT: 41.68±4.02) were higher in GT group. Altogether, these data provide evidence that AST improved antioxidant defense, which may be associated with increased glycogen content and cell growth, hypertrophic level, skeletal muscle of animals.