RESUMO
OBJECTIVE: Doxorubicin (DOX) is an effective chemotherapeutic agent used in the treatment of various neoplasms. Nevertheless, its therapeutic efficacy is hampered by life-threatening heart failure. Therefore, the current study was undertaken to investigate whether dichloroacetate (DCA), a metabolic and mitochondrial modulator, when administered at a therapeutically feasible dose could potentially reverse acute DOX cardiotoxicity. Furthermore, the possible underlying mechanisms of cardioprotection were also assessed. MATERIALS AND METHODS: Different techniques were performed to assess cardiac injury like echocardiography, histopathology, transmission electron microscope, biomarkers of cardiac injury, and oxidative stress markers. Further, the expression levels of mRNA and protein were quantified by PCR and immunohistochemistry, respectively. RESULTS: Echocardiography showed that mice that received DOX/DCA combination were protected against heart failure. Additionally, histopathology and transmission electron microscopy revealed structural damage alleviation by DOX/DCA combination, which was confirmed biochemically via significant suppression of elevated CK-MB and AST levels. Mechanistically, DOX dysregulated the expression of PGC-1α and SIRT-3 genes which are key to normal mitochondrial functioning. Of note, co-treatment with DCA effectively restored PGC-1α/SIRT-3 signaling and normalized the mitochondrial DNA index. Moreover, events downstream of DOX-triggered mitochondrial dysfunction such as oxidative stress and p53-dependent apoptosis were all abrogated by combination with DCA. CONCLUSIONS: The present study is the first to provide in vivo evidence that DCA is effective in protecting against acute DOX cardiotoxicity. Additionally, the study highlights the potential of administering metabolic modulators to safeguard against DOX cardiotoxicity.
