Protective effects of ginsenoside Rc against acute cold exposure-induced myocardial injury in rats.

Ginsenoside Rc is one of the cardinal bioactive components of Panax ginseng. The present study aimed to investigate whether ginsenoside Rc exerted protective effects against acute cold exposure-induced myocardial injury in rats. Forty rats were randomly assigned into four groups: Control, model, ginsenoside Rc 10 mg/kg, and 20 mg/kg groups. Rats were intragastrically administrated with ginsenoside Rc (10, 20 mg/kg) or vehicle daily for 7 days. On the seventh day, all rats except the control group were exposed to low temperature. Cardiac function, myocardial enzyme activities, hemorheology, and inflammatory response were detected. Histopathological examination and apoptosis of cardiac tissues were performed. The expressions of silent information regulator 1 (SIRT1), B-cell lymphoma (Bcl-2), Bcl-2-associated X (Bax), procaspase-3, and the mRNA (messenger RNA) level of SIRT1 were measured by western blot and real-time quantitative polymerase chain reaction (PCR) analysis. Ginsenoside Rc significantly improved cardiac function, diminished the activities of lactate dehydrogenase (LDH), aspartate aminotransferase, and creatine kinase isoenzyme (CK-MB), and regulated abnormal hemorheology in acute cold-exposed rats (p < 0.05 or p < 0.01). Furthermore, ginsenoside Rc could attenuate myocardial histological changes and structural abnormalities, decrease apoptotic cells and reduce the mRNA levels and activity of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 (p < 0.01). In addition, ginsenoside Rc upregulated the expressions of SIRT1, Bcl-2, and procaspase-3 and downregulated that of Bax (p < 0.01). The changes in both the mRNA and protein expression levels of SIRT1 were similar. The results of the current study suggested that ginsenoside Rc could alleviate acute cold exposure-induced myocardial injury in rats by inhibiting cardiomyocyte apoptosis via regulating SIRT1 expression and attenuating the inflammatory responses. PRACTICAL APPLICATION: The current study indicated that ginsenoside Rc could alleviate acute cold exposure-induced myocardial injury in rats. Ginsenoside Rc could be potentially used as a bioactive ingredient in processed functional food products or food supplements to prevent from acute cold exposure-induced myocardial injury.