Efeito protetor do treinamento de corrida na cardiotoxicidade induzida pela doxorrubicina em ratos wistar

Abstract

Introduction: Doxorubicin is widely used as a chemotherapy agent in the treatment of different types of cancer. Although it is very effective, it is known to be highly cytotoxic, which leads to serious cardiac damage, compromising the quality of survival of patients. Therefore, many cardioprotective therapy strategies have been investigated, and aerobic exercise has been very promising. Objective: To evaluate whether aerobic training on a treadmill performed before exposure to chemotherapy is capable of maintaining performance and attenuating the cardiotoxicity induced by Doxorubicin. Material and Methods: 39 Wistar rats were used, with a mean age of 3 months and body weight between 250 and 300 grams, divided into 4 groups, Control (C), Doxorubicin (D), Trained (T), Trained + Doxorubicin (TD). The animals in groups T and TD were collected during running training on a treadmill for 4 weeks prior to treatment with Doxorubicin. The animals in groups D and TD received intraperitoneal injections of Doxorubicin hydrochloride, three times a week, over two weeks, reaching a total cumulative dose of 7.5 mg/kg. Results: An increase in total collagen fibers was observed in group D, which did not increase when the treatment was associated with exercise. In addition, we observed attenuation in the increase in the number of cardiac mast cells in animals treated with doxorubicin and running training. In the echocardiogram, we observed a lower value in group D in relation to group C in the following variables: end-systolic volume (ESV-51%); end-diastolic volume (EDV-44%); left ventricular diameters in systole (LVDs-22%); left ventricular diameter in diastole (DIVEd-14%) and stroke volume (SV-40%). Running training was able to maintain the resistance of animals treated with doxorubicin compared to animals in groups C and D. Conclusion: Running training was able to maintain the endurance of animals treated with doxorubicin compared to animals in groups C and D. Aerobic training on a treadmill maintains the performance of rats treated with doxorubicin and attenuates the cardiac damage from cardiotoxicity, evidenced by maintenance of interstitial collagen fibers and mitigation of the increase in the number of mast cells when treatment was associated with training.