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Background and purpose: One of the main issues in cancer treatment is to reduce the side effects of drugs on healthy tissues. The aim of this study was to investigate the preventative effects of continuous aerobic exercise on apoptosis ratio and liver fibrosis induced by doxorubicin in aging rats.
Materials and methods: In this experimental research, 42 adult Wistar rats were randomly divided into 6 groups (n= 7), including the Young, Aged, Aged+ Saline, Aged+ Dox, Aged+ Exercise+ Saline, and Aged+ Exercise+ Dox. The training groups practiced on treadmill while considering the principle of overload (five sessions per week/ six weeks). On the last 15 days of exercise, doxorubicin or saline solution were injected (1 mg/kg/daily). Then, 48 hours after completing the trainings, liver tissue sampling was performed to evaluate the fibrosis and expression of Bax and Bcl-2 proteins. Data analysis was done using One-way ANOVA at a significant level of P≤0.05.
Results: Doxorubicin caused a significant increase in liver fibrosis, expression of Bax protein and Bax/Bcl-2 ratio, and a significant reduction in expression of Bcl-2 protein (p≤0.05). On the other hand, aerobic training significantly reduced the expression of Bax protein, Bax/Bcl-2 ratio and hepatic fibrosis, and significantly increased the expression of Bcl-2 protein (p≤0.05).
Conclusion: Continuous aerobic exercises, reduce the Bax/Bcl-2 ratio which is an indicator of increase in survival rate and also reduce liver fibrosis against doxorubicin.