Quercetin Reduces the Susceptibility to Cardiac Reperfusion Arrhythmias in Ovariectomized Rats

Cardiovascular diseases (CVDs) are the leading cause of death globally. Decrease in female sex hormones during menopause increases the risk of cardiovascular disease, mainly ischemic heart disease (IHD). Quercetin, a flavonoid, has beneficial properties in CVDs due to its antioxidant, anti-inflammatory, and anti-apoptotic effects. The aim of this study was to investigate the effects of quercetin on susceptibility to cardiac reperfusion arrhythmias and mitochondrial function in ovariectomized rats (OVX). Three-month-old Wistar female rats were randomly assigned to the following experimental groups: SHAM-operated, vehicle-treated (DMSO 10% + PBS, 1 mL kg^-1); OVX (vehicle-treated); and OVX+Q (25 mg·kg^-1). The three experimental groups were carried out for 4 weeks (five times a week) by oral gavage. Quercetin treatment effectively decreased myocardial infarct size and susceptibility to reperfusion arrhythmias. Quercetin treatment was also effective in preventing mitochondrial swelling, while increased ATP production compared to the OVX group. In conclusion, our results indicate that quercetin could have a therapeutic effect in preventing some of the pathophysiological changes caused by low estrogen levels in the cardiovascular system.