Effects of Resistance Exercise Training on Doxorubicin-Induced Cardiotoxicity

Although highly effective, doxorubicin (DOX) use is limited by a dose-dependent cardiotoxicity. The purpose of this study was to determine whether resistance training (RT) would protect against DOX-induced cardiac dysfunction and determine whether any observed functional preservation is a result of reduced lipid peroxidation or a preservation of the cardiac myosin heavy chain (MHC) isoform distribution. Rats were resistance-trained or remained sedentary for 12 weeks, then treated with 12.5 mg/kg DOX or 0.9% saline. Five days after DOX exposure, cardiac function, lipid peroxidation, and MHC isoform expression were quantified. RT preserved cardiac function and attenuated the α-to β-MHC shift that occurs with DOX treatment. No significant differences in lipid peroxidation were observed between sedentary and RT animals treated with DOX. These data suggest that resistance-type exercise can provide protection against DOX-induced cardiac dysfunction, which may be a result of a preservation of the cardiac MHC isoform distribution.