The effect of eight weeks of high intensity interval training on cardiac tissue of p-AMPK, T-AMPK and fibrosis and glycemic index in male Wistar diabetic rats

  Intense interval training (HIIT) activates metabolic factors by increasing the cell's need for energy in the shortest time; However, its role in AMPK activation and subsequent reduction of cardiac tissue fibrosis in type 2 diabetes (T2DM) patients is unclear. Therefore, the present study was conducted to determine the effect of eight weeks of High intensity interval training on AMPK levels and cardiac tissue fibrosis, fasting blood glucose and insulin, and insulin resistance in streptozocin-induced diabetic rats.

In this experimental study, 20 heads (293.16 ± 49.96 g) of adult white Wistar rats were divided into four groups (n=5): healthy control, diabetic control, healthy exercise, and diabetic exercise. The HIIT protocol was performed on a treadmill for eight weeks (five sessions per week including three phases of warm-up, main body of exercise and cool-down in each session). The training intensity was 85-90% of the maximum speed (~27-30 m/min) in 6-12 two-minute intervals with a three-minute active rest, including continuous running at an intensity of 30% of the maximum speed on the treadmill. Shapiro-Wilk, 2x2 two-way analysis of variance, one-way analysis of variance and Bonferroni's post hoc tests at a significance level of <0.05 were used to analyze the data.

A significant increase in p-AMPK and p-AMPK/T-AMPK values ​​of heart tissue was observed in healthy exercise rats compared to other groups (p<0.05). Also, cardiac tissue fibrosis in the diabetic exercise group was significantly reduced compared to the diabetic control group (p<0.05). However, in the diabetic exercise group, the values ​​of p-AMPK and p-AMPK/T-AMPK in cardiac tissue were not affected (p>0.05) and Also, T-AMPK showed a significant increase in the diabetic control group compared to other groups (p<0.05).

Probably, reduction of cardiac tissue fibrosis in T2DM rats, at least during eight weeks of HIIT, is independent of AMPK.