Red wine increases the expression of human endothelial nitric oxide synthase: A mechanism that may contribute to its beneficial cardiovascular effects

OBJECTIVES: The study tested the effect of red wine on endothelial-type nitric oxide synthase (eNOS) expression and eNOS activity in human endothelial cells. BACKGROUND: Endothelial-type nitric oxide (NO) synthase exerts vasoprotective effects. Moderate alcohol consumption has been associated with a reduction of cardiovascular disease, and red wine seems to offer more benefits than any other type of drink. However, the molecular basis of this protective effect is unclear. METHODS: Human endothelial cells were treated with red wine, and eNOS messenger ribonucleic acid (mRNA) expression was measured by RNase protection assay, eNOS protein expression by Western blotting, and eNOS activity by RFL-6 reporter cell assay. The eNOS promoter activity was analyzed in transfected endothelial cells; binding activities of relevant transcription factors were determined by electrophoretic mobility shift assay. RESULTS: Incubation of endothelial cells with red wines from France upregulated eNOS mRNA and protein expression. In contrast, red wines from Germany showed little or no effect on eNOS expression. No significant difference in eNOS mRNA expression could be detected between "en barrique" (matured in oak barrels) and "non-barrique" (matured in steel tanks)-produced French red wines. Endothelial cells treated with French red wines produced up to three times more bioactive NO than did control cells. French red wines increased the activity of the eNOS promoter, with the essential trans-stimulated sequence being located in the proximal 326 bp of the promoter sequence. The eNOS mRNA stability was also increased by red wine. CONCLUSIONS: The increase in eNOS expression and activity brought about by red wines from France (and probably other locations) may contribute to the beneficial effects of this beverage on the cardiovascular system.