Resveratrol Attenuates Ischemia/Reperfusion Injury in Neonatal Cardiomyocytes and Its Underlying Mechanism

This study was designed to investigate whether Resveratrol (Res) could be a prophylactic factor in the prevention of I/R injury and to shed light on its underlying mechanism. Primary culture of neonatal rat cardiomyocytes were randomly distributed into three groups: the normal group (cultured cardiomyocytes were in normal conditions), the I/R group (cultured cardiomyocytes were subjected to 2 h simulated ischemia followed by 4 h reperfusion), and the Res+I/R group (100 µmol/L Res was administered before cardiomyocytes were subjected to 2 h simulated ischemia followed by 4 h reperfusion). To test the extent of cardiomyocyte injury, several indices were detected including cell viability, LDH activity, Na⁺-K⁺-ATPase and Ca²⁺-ATPase activity. To test apoptotic cell death, caspase-3 activity and the expression of Bcl-2/Bax were detected. To explore the underlying mechanism, several inhibitors, intracellular calcium, SOD activity and MDA content were used to identify some key molecules involved. Res increased cell viability, Na⁺-K⁺-ATPase and Ca²⁺-ATPase activity, Bcl-2 expression, and SOD level. While LDH activity, capase-3 activity, Bax expression, intracellular calcium and MDA content were decreased by Res. And the effect of Res was blocked completely by either L-NAME (an eNOS inhibitor) or MB (a cGMP inhibitor), and partly by either DS (a PKC inhibitor) or Glybenclamide (a K_ATP inhibitor). Our results suggest that Res attenuates I/R injury in cardiomyocytes by preventing cell apoptosis, decreasing LDH release and increasing ATPase activity. NO, cGMP, PKC and K_ATP may play an important role in the protective role of Res. Moreover, Res enhances the capacity of anti-oxygen free radical and alleviates intracellular calcium overload in cardiomyocytes.