The Expression of Nitric Oxide Synthase (NOS) Isoforms in relation to Resveratrol Administration in Hypoxic Injury of Myocardial Cells

ABSTRACT

PURPOSE: Resveratrol (trans-3,4',5-trihydroxystilbene), abundant in skin of grapes and red wines, has been known to protect heart cells from hypoxia/ischemia injury through its anti-oxidant properties and may also exert its cardioprotective action. There, to date, are no reports about the relationship with nitric oxide (NO)-mediated mechanism. Therefore, we investigated whether resveratrol can regulate the expression of NO synthase (NOS) in an in vitro hypoxic model of cultured H9c2 cardiomyoblasts. METHODS: The cultured H9c2 cardiomyoblasts were divided into four groups a normal control group, a hypoxic group, two groups each treated with resveratrol before and after hypoxic insult. The control cells were placed in 5% CO2 incubator, and the hypoxic and resveratrol-treated groups were placed in 1% O2 incubator. NO activity was determined for all three isoforms of NOS; induced NOS (iNOS), endothelial NOS (eNOS), and neuronal NOS (nNOS) using real-time PCR. RESULTS: The expressions of iNOS and eNOS were decreased in the hypoxic group compared to the control group, whereas the expression of nNOS was greater in the hypoxic group than in the control group. In contrast, the group treated with resveratrol before hypoxic insult showed increased expressions of iNOS and eNOS as compared to the hypoxic group. CONCLUSION: The results of the present study demonstrate that activation of iNOS and eNOS, but not nNOS, may be one of the mechanisms involved in the protective effect on resveratrol against hypoxic myocardial injury.