Ginsenoside Rb3 ameliorates myocardial ischemia-reperfusion injury in rats

Context: Panax ginseng C. A. Mey (Araliaceae) has been widely used in clinic for treatment of cardiovascular diseases in China. Ginsenoside Rb3 is the main chemical component of Panax ginseng. Objective: The aim of this study was to evaluate the effect of ginsenoside Rb3 on myocardial ischemia-reperfusion injury in rats. Methods: Sprague-Dawley rats were orally treated with Rb3 (5, 10 or 20 mg/kg) daily for 3 days followed by subjecting to left anterior descending coronary artery ligation for 30 min and reperfusion for 24 h. Results: This study showed that ginsenoside Rb3 treatment resulted in a reduction in myocardial infarct size. Ginsenoside Rb3 significantly attenuated the changes of creatine kinase activity and lactate dehydrogenase activity. The cardioprotective effect of ginsenoside Rb3 was further confirmed by histopathological examination. Ginsenoside Rb3 alleviated the increase of malondialdehyde content and the decrease of superoxide dismutase activity in left ventricle. Treatment with ginsenoside Rb3 also decreased plasma endothelin and angiotensin II levels. Conclusion: These findings suggested that ginsenoside Rb3 possesses the effect against myocardial IR injury and the underlying mechanism is related to its antioxidant activity and microcirculatory improvement.