Effects of Eight Weeks of High-Intensity Interval Training on the Expression of the Nkx2.5 and Tbx5 Genes in the Heart Tissue of Type 2 Male Diabetic Rats

Exercise and antioxidants consumption are known as protective effect against the risk of diabetes. Therefore, the current study aimed to investigate the effects of eight weeks of high-intensity interval training (HIIT) and thyme honey on the expression of Nkx2.5 and Tbx5 genes in the heart tissue of male type 2 diabetic rats.

This experimental study was performed on 36 male diabetic rats which were randomly divided into four groups of control (n=8), HIIT (n=10), thyme honey (n=8), and HIIT+thyme honey (n=10). The HIIT training intervention was conducted in eight weeks (five sessions per week) and included 2 to 8 intervals with 2 min running at 80%-90% VO2max and 1 min at 50%-56% VO2max. Additionally, the supplement groups consumed 3 g/kg of thyme honey, 5 days/week. Both Nkx2.5 and Tbx5 gene expression in heart tissue were measured using real-time RT-PCR. To evaluate the differences among the groups, ANOVA and LSD post hoc tests were used at the significance level of P≤0.05.

The results revealed that the expression of the Nkx2.5 gene was significantly increased only in the HIIT group, compared to the control group (P=0.03); however, it was not observed in other intervention groups (P>0.05). The expression of the Tbx5 gene was significantly increased in both HIIT (P=0.02) and HIIT+thyme honey (P=0.02) groups, compared to the control group.

The HIIT is associated with increased expression of the Nkx2.5 and Tbx5 genes in the heart tissue of diabetic rats; however, it can not be said exactly that thyme honey has similar effects in diabetic rats.