Red wine polyphenols, in the absence of alcohol, reduce lipid peroxidativestress in smoking subjects

(P)henolic compounds in red wine can exert antioxidant effects on in vitro lipoprotein oxidation, This has led to speculation that red wine consumptio n mediates unique anti-atherosclerotic effects compared to other alcoholic beverages. However, studies assessing the effects of red wine consumption o n lipoprotein oxidation ex vivo have not been conclusive. The recent identi fication of the F-2-isoprostanes as oxidative products of arachidonic acid has provided a reliable measure of in vivo lipid peroxidation. This randomi zed trial investigated changes in plasma and urinary F-2-isoprostane concen trations following red wine, white wine, or dealcoholized red wine consumpt ion in humans, Eighteen male smokers consumed, in random order, red wine, w hite wine, or dealcoholized red wine, for two weeks with one week washout b etween beverages. Plasma and urinary F-2-isoprostane concentrations were me asured before and alter each beverage. Serum gamma -glutamyl transpeptidase (gamma -GT) and urinary 4-O -methylgallic acid were measured as markers of alcohol consumption and phenolic acid absorption, respectively. Plasma F-2 -isoprostanes (p < .05) decreased significantly with dealcoholized red wine but not with the alcohol-containing beverages. Urinary excretion of F-2-is oprostanes showed a similar trend. <gamma>-GT decreased significantly with dealcoholized red wine and increased with both alcohol-containing beverages (p < .01). Urinary excretion of 4-O-methylgallic acid increased significan tly (p < .001) in the 24 h urine samples following red wine or dealcoholize d red wine ingestion, but not with white wine, Serum urate increased and be ta -carotene decreased with both alcoholic beverages relative to dealcoholi zed red wine. There was no change in the antioxidants alpha- and gamma -toc opherol or vitamin C with any of the beverages. The results suggest that po lyphenols in dealcoholized red wine can reduce in vivo lipid peroxidation a s measured by F-2-isoprostanes in smoking subjects. However, no reduction i n lipid peroxidation was observed following red or white wine consumption, suggesting that any protective effects of wine drinking on cardiovascular d isease are unlikely to be related to inhibition of lipid oxidation. (C) 200 1 Elsevier Science Inc.