Mitochondrial transplantation ameliorates doxorubicin-induced cardiac dysfunction via activating glutamine metabolism

Summary: Doxorubicin is a wildly used effective anticancer agent. However, doxorubicin use is also related to cardiotoxic side effect in some patients. Mitochondrial damage has been shown to be one of the pathogeneses of doxorubicin-induced myocardial injury. In this study, we demonstrated that mitochondrial transplantation could inhibit doxorubicin-induced cardiotoxicity by directly supplying functional mitochondria. Mitochondrial transplantation improved contractile function and respiratory capacity, reduced cellular apoptosis and oxidative stress in cardiomyocytes. Mitochondria isolated from various sources, including mouse hearts, mouse and human arterial blood, and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), all exerted similar cardioprotective effects. Mechanically, mitochondrial transplantation activates glutamine metabolism in doxorubicin-treated mice heart and blocking glutamine metabolism attenuated the cardioprotective effects of mitochondrial transplantation. Overall, our study demonstrates that mitochondria isolated from arterial blood could be used for mitochondrial transplantation, which might serve as a feasible promising therapeutic option for patients with doxorubicin-induced cardiotoxicity.