Abstract
Background: The potential role of exercise in physiological cardiac hypertrophy is rooted in both hormonal and genetic components.
Objectives: The aim of this study was to determine the impact of resistance exercise on the expression of PI3K and AKT1 in cardiac tissue of type 2 diabetes (T2D) rats and their physiological cardiac hypertrophy.
Methods: First, 21 male Wistar rats (220±20 g) were obese with 6-week high-fat diet (HFD) and were randomly assigned into non-diabetes, control T2D, and exercise diabetes groups. After inducing obesity, T2D was induced by intraperitoneal injection of streptozotocin (25 mg/kg) for diabetes groups. Rats in the exercise group completed a 6-week resistance exercise program, 5 sessions per week. PI3K/AKT1 expression and the weight ratio of left ventricular to heart, heart to body, and left ventricular to body were compared by analysis of variance (ANOVA) between groups.
Results: In response to the induction of diabetes, the expression of PI3K/AKT1 in heart tissue decreased significantly compared to that of non-diabetic rats (P=0.001 and P=0.001, respectively). Further, resistance training led to a significant increase in PI3K expression (P=0.028) and AKT1 (P=0.032) and the weight ratio of left ventricular to heart (P=0.001), heart to the body (P=0.001), and left ventricular to the body (P=0.001) compared to control diabetic rats.
Conclusion: Resistance training is associated with physiological cardiac hypertrophy in diabetic rats, and this improvement may be attributed to the PI3K/AKT1 signaling pathway.