Protective effect of ginsenoside Rd against isoproterenol-induced myocardial infarction in Wistar rats

Purpose: To investigate the protective effect of ginsenoside Rd (GRd) against isoproterenol (ISO)-induced myocardial infarction in a rat model. Methods: Forty healthy male rats were equally divided into four groups (10/group). Rats in the control group received only saline, whereas rats in GRd group were intraperitoneally (i.p.) injected GRd at a dose of 50 mg/kg body weight (b.wt.) for 14 days. The other two groups were ISO-treated rats. One group (MI model) received ISO at a dose of 80 mg/kg b.wt i.p. for 2 days, while the other group (GRd + ISO group) was pretreated with GRd at a dose of 50 mg/kg for 14 days prior i.p. administration of the same dose of ISO. Results: Treatment with GRd (for 14 days) prior to ISO exposure resulted in significant increase in the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) as well as significant decreases in heart-to-body weight ratio, infarct size, inflammatory markers {tumour nectosis factor alpha (TNF-alpha), nuclear factor kappa B (NF-kappa B), interleukin 1 beta (IL-1 beta) and interleukin 6 (IL-6)}, relative to ISO-treated rats (p > 0.05). In addition, prior exposure to ISO led to significant elevation in malondialdehyde (MDA), cardiac troponin T (cTnT), creatine kinase (CPK), lactate dehydrogenase (LDH) and apoptotic markers (caspase-3 and caspase-9). However, pre-treatment with GRd reversed the ISO-induced histopathological changes (necrosis/oedema and altered cardiac fibres) in cardiac tissue. Conclusion: These results demonstrate that GRd ameliorates ISO-induced cardiotoxicity in rats via upregulation of the activities of antioxidants, and suppression of inflammatory and apoptotic biomarkers. Thus, GRd has cardio-protective properties.