The effects of endurance training and pumpkin seed consumption on oxidative stress and DNA damage markers in the cardiac muscle of rats poisoned with H2O2

Introduction: Oxidative stress can impair the antioxidant protective capacity of the body, which is associated with decreased capacity of the body's internal defense system. There are some evidences that training and pumpkin seed (PS) consumption by different mechanisms have a protective effect on myocardial tissue by inhibiting oxidative stress. The aim of the present study was to investigate the effects of endurance training (ET) and PS consumption on oxidative stress and DNA damage markers in the cardiac tissue of rats poisoned with H2O2. Materials and methods: In this experimental study, 42 healthy male Wistar rats were randomly divided into 7 groups, including: 1) control, 2) H2O2, 3) H2O2+ET, 4) H2O2+1mg/kg PS, 5) H2O2+2 mg/kg PS, 6) H2O2+ET+ 1 mg/kg PS, and 7) H2O2+ET+2 mg/kg PS. During eight weeks, groups 2 to 7 received 1 mg/kg of H2O2 (manufactured by Sigma Aldrich Co.) peritoneally; also, groups 3, 6, and 7 ran for 30 minutes on a treadmill at a speed of 23 m/min for 5 sessions per week. Independent sample t-test and two-way ANOVA with Bonferroni’s post- hoc tests were used to analyze the data (P<0.05). Results: H2O2poisoning significantly decreased ATP and increased cytochrome-C, MDA and PAB (P=0.001); on the other hand, ET and PS consumption alone significantly increased ATP and decreased cytochrome-C and MDA (P=0.001); but the interactive effects of ET and PS consumption on increase of ATP and decrease of cytochrome-C, MDA and PAB were not significant (P>0.05). In addition, although consumption of 1 mg/kg PS had no significant effect on increase of ATP and decrease of cytochrome-C and MDA (P>0.05), 2 mg/kg PS significantly increased ATP and decreased cytochrome-C, MDA and PAB (P<0.05). Conclusion: It seems that ET and PS consumption alone can be a good strategy to reduce the adverse effects of toxicity by inducing oxidative stress; however the effects of PS are dose-dependent.