Attenuation of ROS-mediated myocardial ischemia-reperfusion injury by morin via regulation of RISK/SAPK pathways

Background Oxidative stress plays an important role in the pathogenesis of myocardial ischemia-reperfusion (IR) injury. Morin, a bioflavonoid, has demonstrated antioxidant, anti-inflammatory and other diverse pharmacological activities in various experimental models such as isoproterenol-induced myocardial injury, doxorubicin-induced cardiotoxicity and neurotoxicity, as well as cisplatin-induced nephrotoxicity. Thus, this study aimed to evaluate the effect of morin in myocardial IR injury model and its underlying mechanisms. Method To accomplish this, male albino Wistar rats were pre-treated with morin (40 and 80 mg/kg; po) for 28 days and on 29th day, rats experienced 45-min myocardial ischemia followed by 60-min reperfusion. Results In comparison to IR-control group, morin pre-treatment significantly normalized hemodynamic parameters, restored antioxidant status, improved pathological changes, reduced the release of cardiac injury markers, inhibited inflammation (TNF-alpha/IL-6/NF kappa B/IKK beta) and apoptosis (increased Bcl-2, decreased Bax/Caspase-3 and TUNEL positivity) in the myocardium. This improvement in antioxidant, inflammation and anti-apoptosis markers could be due to downregulation of SAPK (p38/JNK) pathway and upregulation of survival kinase, i.e. RISK pathway (ERK/eNOS) in the myocardium. Conclusion Thus, morin attenuated myocardial IR injury in rats by regulation of RISK/SAPK pathways. Graphic abstract