Effect of 4 weeks high intensity interval training on gene expression of Ryanodine receptor calcium channels (RyR2), SERCA2a and Phospholamban in diabetic rat's heart

Diabetic cardiomyopathy (DCM) is one of the most important complications of diabetes and is one of the major causes of death in diabetic patients. DCM at the molecular level is rooted in down regulation of expression or activity of those various proteins involved in maintenance or regulation of intracellular calcium homeostasis. The aim of this study was to investigate the effect of 4 weeks of high intensity interval training (HIIT) on gene expression of calcium channel of ryanodine receptors (RyR2), SERCA2a and phospholamban (PLB) in the heart of diabetic male rats. In this experimental study, 24 male Wistar rats were divided into two groups: sedentary control and HIIT. Diabetes was induced in both groups by intraperitoneal injection of Streptozotocin (STZ) solution. 24 hours after the last training session, the rats were euthanized and their left ventricle was extracted. Real Time-PCR technique was used to determine the gene expression of RyR2, SERCA2a and PLB. To compare the two groups, independent t test was used at alpha level of 0.05. The results revealed that 4 weeks of HIIT significantly increased gene expression of RyR2 in the left ventricle of the heart of HIIT group (P=0.03). Although gene expression of SERCA2a and phospholamban increased, they were not significantly different. Based on these findings, it can be concluded that 4 weeks of HIIT could prevent and minimize the maladjustments in these 2 proteins affecting cycle of cardiac contraction and reduce the risk of diabetic cardiomyopathy through increased RyR2 gene expression in the heart of diabetic rats.