Comparison of the effect of 8 weeks of endurance training in the morning and at night on gene expression of some mitochondrial biogenesis factors in the heart of male diabetic rats

Due to the increasing development of metabolic diseases such as diabetes, the heart is one of the most important tissues that are damaged by this disease. Also, long-term oxidative stress in the heart tissue causes changes in the expression of various genes, including mitochondrial biogenesis genes. The effect of exercise in different phases of the circadian cycle on the protection of heart tissue in diabetes is unknown. The aim of this study was the effect of endurance training in the light and dark phase on some indicators of mitochondrial biogenesis in the heart tissue of diabetic rats. In this study, 30 NMRI mice with an average age of 8 to 10 weeks were randomly divided into 6 groups: dark phase healthy control, light phase healthy control, dark phase diabetic control, light phase diabetic control, dark phase diabetic exercise, and exercise. Diabetics were placed in the light phase. Then they became diabetic by feeding with high-fat diet and intraperitoneal injection of streptozotocin. The endurance training protocol (Vmax 50-60%) was 5 days a week for 8 weeks. After anesthesia, blood and heart tissue were removed. The data were evaluated by ANOVA method at a significance level of p < 0.05. 8 weeks of endurance training significantly increased the expression of PGC-1α, NRF-1, Atf2, AMPK genes (P˂ 0.05) in the heart tissue of diabetic rats. The changes in the two phases of light and darkness in different groups did not show any significant difference (P˂ 0.05). Endurance training can lead to better performance by increasing the expression of mitochondrial biogenesis genes in the heart tissue of subjects with diabetes. Endurance activity in two phases of light and dark has no significant difference in the desired factors and more research is needed.