Protective effects of S-carvedilol on doxorubicin-induced damages to human umbilical vein endothelial cells and rats.

Doxorubicin (DOX) is a highly active anticancer drug with severe cytotoxicity, which is strongly associated with oxidative stress. Carvedilol (CAR), used as its racemate with S-CAR and R-CAR (1:1), has been previously reported to ameliorate the DOX-induced cytotoxicity. However, the main contributor from CAR of its protective effects has not been clear. Therefore, in this study, we aimed to investigate further the different effects of CAR enantiomers on DOX-induced cytotoxicity in human umbilical vein endothelial cells and rats, respectively. Results indicated that S-CAR could significantly attenuate DOX-induced cell death, apoptotic morphological changes, decrease the mitochondrial membrane potential and oxidative stress responses by increasing the superoxide dismutase and catalase activities, and decreasing malondialdehyde contents and reactive oxygen species levels via the phosphoinositide 3-kinase/AKT/endothelial nitric oxide synthase pathway in vitro. Consistent with the in vitro study, the protective effects of S-CAR on the myocardial tissues and hemodynamics were also detected in rats suffering because of DOX treatment. With the obtained results, we can first conclude that S-CAR provides superior protection to injury induced by DOX relative to that of racemic CAR and R-CAR.