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

Introduction: 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. Material & Methods: 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. (Ethic code: IR.SSRC.REC.1399.080) Findings: 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. Discussion & Conclusion: 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.