Effect of Aerobic Exercise Training on Left Ventricular Apoptotic and Antioxidant Indices in High Fat Diet and Streptozotocin-induced Type 2 Diabetic Rat Model

Exercise training has been suggested as a potential non-pharmacological strategy to prevent cardiovascular injuries. However, the role of exercise is controversial in preventing the progression of injuries caused by diabetic cardiomyopathy or their repairing. Therefore, this study aimed to evaluate the effect of aerobic exercise training on left ventricular apoptotic and antioxidant indices in a high-fat diet and streptozotocin-induced type 2 diabetic rat model.

  Twenty-four male Wistar rats, 7-8 weeks of age, were randomly divided into two groups of normal diet (n = 8, ND) and high-fat diet (n = 16, HFD). The high-fat diet rats were given a free diet containing 55% fat for four weeks. For diabetes induction, 30 mg/kg of streptozotocin (STZ) was injected intraperitoneally into obese rats. Diabetic rats were subdivided into two groups: control diabetic (n= 8, CD) and diabetic-training (n = 8, TD) groups. The training group performed aerobic exercises on a treadmill for four weeks. The normal diet and control diabetic groups did not receive any exercise training.

Diabetes caused left ventricular catalase activity (p=0.001) reduction and increased caspase-9 (p=0.001) and P53 (p=0.001). Exercise training increased the maximum oxygen consumption rate by 37% (p=0.003) in the diabetic rats. The TD group had lower HOMA-IR (p=0.01) and plasma glucose (p=0.003) than the CD group. Also, aerobic training increased catalase (p=0.01) but decreased caspase-9 (p=0.001) and P53 (p=0.005) in the diabetic rats.

Progressive aerobic exercise training can contribute to insulin resistance amelioration by increasing catalase activity and reducing apoptotic indices. Therefore, aerobic exercise training can be used as an effective non-pharmacological method of treating diabetic cardiomyopathy.