Endocrine Abstracts

Low circulating sex hormone-binding globulin (SHBG) is an independent risk factor for cardiovascular disease. Mediterranean diet has been associated with a decreased risk of cardiovascular disease. We have recently shown that olive oil consumption is associated with elevated SHBG serum levels and that PPARγ downregulation induced by oleoyl-CoA is an important underlying mechanism of such regulation. Red wine is also an important component of the Mediterranean diet and its moderate consumption has health benefits on cardiovascular and metabolic disease. The aim of the present study was to investigate whether treatment with red wine could increase SHBG levels in HepG2 cells and the molecular mechanisms involved. We performed treatments in HepG2 cells with red wine, white wine or ethanol (as a control) during 3 days. Our results showed that red wine treatment increased SHBG (mRNA and protein) when compared with white wine and ethanol treatments in HepG2 cells. Since the concentration of the polyphenolic compound resveratrol in red wine is higher than in white wine, we next wanted to study if resveratrol could increase SHBG production over the course of 3 days in HepG2 cells. The results showed that resveratrol (10 or 25 μM) treatment was able to increase SHBG levels (mRNA and protein) in a dose-dependent manner when compared with vehicle-treated HepG2 cells. This effect was not mediated by HNF4α and PPARγ, two important transcription factors involved in SHBG regulation. In conclusion, resveratrol, a component of red wine, increases SHBG production in HepG2 cells. Our results suggest that the cardioprotective effect of red wine could be mediated in part by increasing SHBG levels. However, further studies are needed to elucidate the exact molecular mechanisms underlying SHBG upregulation by resveratrol.