To evaluate the role of wine polyphenols and that of alcohol on lipid peroxidation indexes and membrane composition in the liver, 40 Sprague-Dawley rats were fed for 28 days with a commercial AIN-76 diet to which was added one of four different beverages: red wine, alcohol solution, dealcoholated wine, or water. The beverage provided 26°7o of the caloric intake. Peroxidation indexes and antioxidative enzymes were determined: no significant differences were detected in catalase and glutathione peroxidase whereas superoxide dismutase was significantly lower in the wine-treated animals (220.3 + 15.4 vs. 342.2 + 43.0 U/mg protein of controls). The following significant differences in hepatic variables were observed: increased ct-tocopherol concentration in the alcohol group
(0.17 + 0.02 vs. 0.11 + 0.01 microg/rag protein of controls); increased concentration of cytochrome P450 in the rats given wine (0.75 + 0.06 vs. 0.51 + 0.08 nmol/mg protein of the alcohol group); increased concentration of cytochrome b5 in wine and dealcoholated wine treatment groups (0.30 +/- 0.01 vs. 0.23 +/- 0.02 nmol/mg protein of controls). The liver membrane fatty acid composition of the wine and dealcoholated wine groups was similar and showed an increase in the saturated fatty acid percentage and a decrease in the polyunsaturated one. The data presented indicate that the main action of polyphenols seems to be an induction of cytochrome activity and that the modality of red wine administration adopted combined with an adequate diet does not provoke any apparent physiological effect on the animals.
