Green Tea, Cocoa, and Red Wine Polyphenols Moderately Modulate Intestinal Inflammation and Do Not Increase High-Density Lipoprotein (HDL) Production

Abstract

Although polyphenols are often merely perceived as antioxidants, their biological activities are manifold and include anti-inflammatory actions. A new area of research on polyphenols and health concerns their putative role in cholesterol metabolism, in particular, their high-density lipoprotein-cholesterol (HDL-c)-raising potential. Indeed, some human studies showed that administration of polyphenol-rich foods such as cocoa, green tea, and extra virgin olive oil modulate and increase HDL-c concentrations. This study assessed the effects of polyphenols on intestinal inflammation, using the physiologically relevant Caco-2 Transwell model and using lipopolysaccharide (LPS) to trigger inflammation. This study also investigated the mechanisms of actions behind the proposed HDL-c-increasing effects of polyphenols. The data suggest that polyphenols (at least those from red wine, cocoa, and green tea) administered at a dietary dose moderately modulate intestinal inflammation but do not increase cholesterol secretion by intestinal cells or enhance HDL functionality. Nutraceuticals and supplements provide pharmanutritional doses that might, conversely, produce beneficial effects.