Modulatory Effect of Aerobic Exercise Training on Doxorubicin-Induced Cardiotoxicity in Rats with Different Ages

We tested the hypothesis that aerobic exercise training (AET) would modulate doxorubicin-induced cardiotoxicity in rats of various ages. Wistar male rats (n = 72) were assigned to three groups (young, adult, and elderly) with three subgroups for each age: doxorubicin (DG, n = 8), AET + doxorubicin (AETDG, n = 8), AET + Saline (AETSG, n = 8). Following the AET intervention, rats were anesthetized and killed to collect heart tissues in order to determine heat shock protein 70 (HSP70), superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-10 (IL10), and c-reactive protein (CRP). Greater levels of SOD and lower levels of MDA were found in young as compared to elderly rats (P < 0.05). CRP was significantly lower in young as compared to adult and elderly rats, respectively (P < 0.05). IL10 also was significantly lower in young as compared to elderly rats (P < 0.05). Furthermore, lower HSP70 and SOD levels were found in DG as compared to AETDG and AETSG (P < 0.05). Conversely, MDA and CRP were significantly higher in DG as compared to other groups (P < 0.05). A significant higher IL10 was noted in DG as compared to AETDG (P < 0.05). Our findings suggest that AET prior to doxorubicin treatment could be useful in minimizing toxicity after chemotherapy with doxorubicin mainly up-regulating of antioxidant defense capacity, with greatest benefit in the young group. Future studies examining the exercise-induced changes and age-related differences following chemotherapy are necessary in human.