The Therapeutic Effect of Endurance Training on Adriamycin-induced Cardiac Stress in Rats

Document Type : Original Article

Abstract

Abstract
Purpose: In recent years, by understanding the free radical mechanism of Adriamycin(ADR)-induced 
cardiac stress, it has become possible to develop effective strategies to prevent or modify their expected 
damages. Several strategies for detecting and preventing cardiac stress have been developed, including 
physical activity or limiting their accumulation. The purpose of this study was to determine the preventive 
effects of endurance training on various doses of adriamycin-induced cardiac stress in rats.
Material and Methods: Forty-eight male rats were randomly assigned to non-training (NT) and training (T) 
groups with three subgroups; including ADR10mg.kg
-1
, ADR20mg.kg
-1 and saline treatment. Training program 
included treadmill running for 25 to 54 min/day, 15 to 20 m/min, 5 days/week, for 6 weeks. After the last 
exercise session of the training groups, a new randomization of all groups into subgroups was performed as 
follows: non-training+saline(NT+saline); non-training+ADR10mg.kg
-1
(NT+ADR10); nontraining+ADR20mg.kg
-
1
(NT+ADR20); training+saline(T+saline); training+ADR10(T+ADR10) and training+ADR20(T+ADR20) and 
afterwards, injections were performed. Rats in all the groups were anesthetized with ketamine and xylazine 
after 10 to 12 hours of overnight fast. 
Results: 20mg.kg
_1 of ADR administration, caused an imbalance in markers related to cardioprotection(HSP70, 
SOD) and cardiac stress (MDA, CPK-MB, CK), as compared to NT+saline group. Preventive effect of 
endurance exercise in the presence of ADR with10 and 20mg.kg
_1 caused a significant increase in HSP70, SOD and 
an insignificant and significant decrease in MDA, an insignificant decrease and a significant increase in CPKMB and an insignificant decrease in total CK in comparison with NT+ADR10 and NT+ADR20 respectively. 
However, there was no significant difference between T+ADR10mg.kg
_1 and T+ADR20mg.kg
_1 in HSP70, MDA and 
total CK but there were significant differences in SOD and CPK-MB. ADR-induced cardiac stress is related to 
oxidative stress.
Discussion and Conclusions: Our study suggests that pre-treatment with endurance exercise may be 
considered as a potentially useful strategy for improving myocardial tolerance against ADR-induced oxidative 
damage. The biochemical mechanisms through which pre-treatment with endurance exercise training exerts its 
potential antioxidant properties, protects cardiac muscle tissue against the toxicity ADR-induced

Keywords

• Endurance training
• Adriamycin
• Cardiotoxicity
• HSP70

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