Mechanisms mediating the cardioprotective effect of carvedilol in cadmium induced cardiotoxicity. Role of eNOS and HO1/Nrf2 pathway.

Cadmium (Cd) is a highly toxic heavy metal with several harmful effects including cardiotoxicity. For the first time, we aimed to evaluate the possible cardioprotective effect of carvedilol (CAR) in Cd induced cardiotoxicity and study the mechanisms involved in such protection including endothelial nitric oxide synthase (eNOS) and HO1/Nrf2 pathway. CAR (1,10 mg/kg/d) was administered orally for 4 weeks with Cd induced cardiac injury (3 mg/kg/d) orally for 4 weeks. We measured cardiac enzymes, mean arterial pressure changes, heme oxygenase-1 (HO1) and total antioxidant capacity (TAC). Moreover; cardiac tissue malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), western blotting of caspase3 and eNOS levels and histopathology were evaluated. Immunoexpression of eNOS in cardiac tissue, gene expression changes of HO1, and nuclear factor erythroid 2-related factor 2 (Nrf2) using real time polymerase chain reactions (rtPCR) were detected. Our results showed that CAR could significantly decrease Cd induced cardiotoxicity.