Comparison of the Effects of Aerobic Training with Vitamin C and Estradiol on Markers of the Liver among Ovariectomized and Normal Rats

Introduction: Postmenopausal estrogen deficiency, disturbance of the antioxidant defense system, and free radical production lead to oxidative stress. This results in metabolic disturbances affecting the liver. Therefore, it is important to properly evaluate the benefits of antioxidant administration and exercise on oxidative stress in the liver. The main purpose of this study was to compare the effects of aerobic training with vitamin C and estradiol on oxidative stress in the liver among ovariectomized and normal rats.   Materials & Methods: In total, sixty-four female rats were divided into two groups of normal (n=32) and ovariectomized (n=32). Each group was subdivided randomly into four subgroups consisting of sham, training, training+vitamin C, and training+estradiol. The experimental protocol was five 60-min running sessions for six weeks on a treadmill with average intensity and 55% Vo2max. Moreover, the rats were subjected to the injection of 250 mg and 0.25 mg/kg vitamin C and estradiol, respectively.  Liver oxidative damage was determined by the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST).   Findings: According to the results, ovariectomy resulted in vaginal atrophy. Moreover, it led to a significant increase in AST and ALT levels. In addition, the administration of estradiol decreased the serum level of these enzymes (P<0.05). However, aerobic training and vitamin C had no effect on the prevention of the increased levels of these enzymes in ovariectomized rats (P<0.05).   Discussion & Conclusions: In conclusion, the obtained results revealed that average intensity training had no effect on the prevention of increased levels of oxidative stress in ovariectomized rats. However, exercise training in combination with estradiol and vitamin C improved oxidative stress conditions in ovariectomized rats.