Introduction: Autophagy is a key anti-aging process and plays a crucial role in maintaining the health of cardiomyocytes. On the other hand, with increasing age, the levels of free radicals (ROS) in cardiac muscle cells and mitochondria increase. Sirtuins are one of the primary molecular pathways involved in autophagy, which is related to cell longevity and enhances antioxidant defense.
Methods: Twenty-four old Wistar male rats with an average weight of 350 ± 50 grams were randomly divided into control, moderate-intensity continuous training (MICT), and high-intensity interval training (HIIT) groups and were trained for 8 weeks. The expression of Sirt1 and Sirt3 genes was measured using the real-time PCR technique, and the concentration of SOD and GPX was measured by optical absorption. To compare the groups, a one-way analysis of variance test was used at the alpha level of 0.05.
Results: The gene expression values of Sirt1 and Sirt3 in the HIIT and MICT groups were significant compared to the control group (percentage change 72.06% and 70.14%, respectively; P< 0.05). There was no significant difference in Sirt1 between the HIIT and MICT groups (percentage change 6.44%; P> 0.05), but a significant difference was observed in Sirt3 (percentage change 31.68%; P< 0.05). The concentration of SOD in both HIIT and MICT groups was significantly higher compared to the control group (percentage change: 26.37% and 23.36%, respectively; P < 0.05). The GPX concentration in both HIIT and MICT groups was also significant compared to the control group (percentage change 43.34% and 18.50%, respectively; P< 0.05).
Conclusion: Both types of exercise, compared to the non-exercise group, modulated the gene expression of Sirt1 and Sirt3, suggesting that exercise likely activates the anti-aging pathway of sirtuins in old rats. Additionally, the concentration of antioxidant factors increased due to exercise, especially high-intensity interval training.