Antioxidant effect of red wine polyphenols on red blood cells

The protective effect of red wine polyphenols against hydrogen peroxide (H2 O2)-induced oxidation was investigated in normal human erythrocytes (RBCs). RBCs, preincubated with micromolar amounts of wine extract and challenged with H2O2, were analyzed for reactive oxygen species (ROS), hemolysis, meth emoglobin production, and lipid peroxidation. All these oxidative modificat ions were prevented by incubating the RBCs with oak barrel aged red wine ex tract (SD95) containing 3.5 mM gallic acid equivalent (GAE) of phenolic com pounds. The protective effect was less apparent when RBCs were incubated wi th wines containing lower levels of polyphenols. Furthermore, resveratrol a nd quercetin, well known red wine antioxidants, showed lower antioxidant pr operties compared with SD95, indicating that interaction between constituen ts may bring about effects that are not necessarily properties of the singu lar components. Our findings demonstrate that the nonalcoholic components o f red wine, mainly polyphenols, have potent antioxidant properties, support ing the hypothesis of a beneficial effect of red wine in oxidative stress i n human system. (C) Elsevier Science Inc. 2000 (J. Nutr. Biochem. 11:114-11 9, 2000) (C) Elsevier Science Inc. 2000. All rights reserved.