Protective Effects of Low-Frequency Magnetic Fields on Cardiomyocytes from Ischemia Reperfusion InjuryviaROS and NO/ONOO⁻

Abstract

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 injury via ROS regulation remains unclear. Methods. To simulate in vivo cardiac 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 (including O2 − 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 (including O2 − 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 was via the phosphorylation of endothelial nitric oxide synthase (eNOS). Conclusion. LFMFs could protect myocardium against I/R injury via regulating ROS generation and NO/ONOO− balance. LFMFs treatment might serve as a promising strategy for cardiac I/R injury.

The effects of glycine, glutamate and their combination on cardiodynamics, coronary flow and oxidative stress in isolated rat hearts

“…Also, Ca 2+ overload due to NMDA receptor activation induce increased H 2 O 2 production in complex I, III and II (41). The lack of a vasodilatory effect of NO in our study could be the consequence of conversion of NO and O 2 − to peroxynitrite, which is one of free radicals with most potent deleterious effect and could mediate the adverse effects of NMDA stimulation by glycine and glutamate (42,43).…”

Low Frequency Electromagnetic Field Conditioning Protects against I/R Injury and Contractile Dysfunction in the Isolated Rat Heart

“…The study of the effects of LF-EMF on the cardiovascular system demonstrated protection against myocardial infarction (MI) [ 7 ]. Similarly, data from Ma and colleagues [ 8 ] suggest that LF-EMFs inhibit the generation of reactive oxygen species, such as nitric oxide and peroxynitrite, thereby protecting cardiomyocytes from I/R and oxidative damage. The protective effects of LF-EMF are further supported by a study examining the effects of LF-EMF on skin wound healing which suggests that LF-EMF stimulates endogenous antioxidant systems.…”

Naringin protects against anoxia/reoxygenation-induced apoptosis in H9c2 cells via the Nrf2 signaling pathway

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