Impact of high-fat diet and resistance training on oxidative stress and cardiac health in rats

Background: When metabolic demands increase due to an obesity-induced high-fat diet (HFD), mitochondrial function is impaired, production can increase, and oxidative stress occurs. This type of stress has been shown to play a key role in various pathological conditions such as heart disease, hypertension, diabetes, chronic kidney disease, and cancers. This study aims to evaluate the impact of HFD and resistance training (RT) on oxidative stress biomarkers and cardiac health in rats. Methods: In this experimental study, 21 male Wistar rats (weighing 200-300 g) were randomly and equally assigned into the following groups: control (CTRL), HFD, and HFD+ RT. Animals in the HFD groups received a high-fat diet for 23 weeks. During the treatments, rats in the HFD+ RT group, besides receiving a high-fat diet, performed the progressive RT protocol three times per week with 30- 100% of their body mass in the last eight weeks. At the end of the treatments, superoxide dismutase (SOD), glutathione peroxidase (GPX), total antioxidant capacity (TAC), and malondialdehyde (MDA) levels in cardiac tissue were measured by colorimetric method. The data were analyzed by one-way analysis of variance (ANOVA) and Tukey’s post hoc test at a significant level of P<0.05. Results: HFD did not alter levels of SOD, GPX, TAC, or MDA in cardiac tissue. Cardiac SOD (P=0.021), GPX (P=0.024), and TAC (P=0.041) levels in the HFD+ RT increased significantly compared to the HFD group, but there was no significant difference in cardiac MDA levels between the three groups (P=0.438). Conclusion: RT seems to improve cardiac tissue oxidative stress adaptations in an animal model fed with an HFD.