Protective Effects of Low-Frequency Magnetic Fields on Cardiomyocytes from Ischemia Reperfusion InjuryviaROS and NO/ONOO−
Background. Cardiac ischemia reperfusion (I/R) injury is associated with overproduction of reactive oxygen species (ROS). Low frequency pulse magnetic fields (LFMFs) have been reported to decrease ROS generation in endothelial cells. Whether LFMFs could assert protective effects on myocardial from I/R injuryviaROS regulation remains unclear.Methods. To simulatein vivocardiac I/R injury, neonatal rat cardiomyocytes were subjected to hypoxia reoxygenation (H/R) with or without exposure to LFMFs. Cell viability, apoptosis index, ROS generation (includingO2-and ONOO−), and NO production were measured in control, H/R, and H/R + LFMF groups, respectively.Results. H/R injury resulted in cardiomyocytes apoptosis and decreased cell viability, whereas exposure to LFMFs before or after H/R injury significantly inhibited apoptosis and improved cell viability (P<0.05). LFMFs treatment could suppress ROS (includingO2-and ONOO−) generation induced by H/R injury, combined with decreased NADPH oxidase activity. In addition, LFMFs elevated NO production and enhanced NO/ONOO−balance in cardiomyocytes, and this protective effect wasviathe phosphorylation of endothelial nitric oxide synthase (eNOS).Conclusion. LFMFs could protect myocardium against I/R injuryviaregulating ROS generation and NO/ONOO−balance. LFMFs treatment might serve as a promising strategy for cardiac I/R injury.