Introduction: Type 2 diabetes is associated with mitochondrial dysfunction and defects in mitophagy. The PINK1–Parkin signaling pathway plays a key role in the removal of damaged mitochondria and maintenance of glucose homeostasis. The aim of this study was to investigate the independent and combined effects of high-intensity interval training and vitamin E PINK1 and Parkin protein levels in type 2 diabetic rats.
Methods: 40 male rats divided into five groups including healthy control, control diabetes, diabetes + exercise, diabetes + vitamin E, and diabetes + exercise + vitamin E. Type 2 diabetes was induced by high-fat diet and injection of streptozotocin. The HIIT protocol was performed for eight weeks and vitamin E supplementation was administered daily. At the end of the intervention period, pancreatic tissue was extracted and PINK1 and Parkin protein expression was measured.
Results: Diabetes induction significantly decreased the expression of PINK1 and Parkin proteins compared to the healthy control group (P<0.001). Both HIIT and vitamin E interventions, alone and in combination, significantly increased the expression of these proteins compared to the diabetic control group (P<0.05); however, no significant difference was observed between the combination group and the individual interventions.
Conclusion: Type 2 diabetes was associated with a significant reduction in pancreatic PINK1 and Parkin expression. HIIT and vitamin E supplementation each independently improved this decrease; however, their combination did not produce a significant additive or synergistic effect. These findings indicate that each intervention may play an effective role in ameliorating mitophagy impairment in type 2 diabetes.