DIFFERENCES IN THE SERUM LEVELS OF ACETALDEHYDE AND CYTOTOXIC ACETALDEHYDE-ALBUMIN COMPLEXES AFTER THE CONSUMPTION OF RED AND WHITE WINE - IN-VITRO EFFECTS OF FLAVONOIDS, VITAMIN-E, AND OTHER DIETARY ANTIOXIDANTS ON CYTOTOXIC COMPLEXES

After the consumption of ethanol, acetaldehyde levels increase in the serum, and the serum develops a nondialyzable cytotoxic activity cause d by the formation of unstable acetaldehyde-albumin complexes. The con centration of acetaldehyde in the serum and the cytotoxic activity in serum albumin 8.5 hr after six healthy volunteers began to drink 94 g of ethanol were significantly less when the ethanol was consumed as re d wine than as white wine. The serum acetaldehyde was measured by a fl uorigenic HPLC assay, and the cytotoxic activity in albumin was determ ined using two different assays based on dissimilar endpoints: (1) det achment of adherent A9 cells and (2) impairment of the ability of A9 c ells to reduce tetrazolium. When serum obtained from five other health y volunteers after the consumption of white wine was incubated at 37 d egrees C for 3 hr with a number of dietary antioxidants at a concentra tion of 100 mu mol/liter, the cytotoxicity of the albumin was markedly reduced. The antioxidants studied consisted of six flavonoids (kaemph erol, fisetin, quercetin, catechin, taxifolin, and coumarin) and three nonflavonoids (salicylic acid, tannic acid, and alpha-tocopherol). In the case of alpha-tocopherol, a statistically significant reduction o f cytotoxicity was observed at a concentration of 10 mu mol/liter. In addition, the cytotoxicity of artificially prepared acetaldehyde-album in complexes was significantly reduced when such complexes were incuba ted with 50 to 100 mu mol/liter of kaempherol, fisetin, quercetin, cou marin or salicylic acid, or 10 mu mol/liter of alpha-tocopherol at 37 degrees C for 3 hr. Evidently, in vitro, flavonoid and nonflavonoid di etary constituents reduce the amount of unstable acetaldehyde-albumin complexes found in both postalcohol serum and in artificially produced acetaldehyde-albumin complexes. The difference in the amount of unsta ble acetaldehyde-albumin complexes found in serum after the consumptio n of red and white wine may therefore be caused by the higher concentr ation of antioxidants, including flavonoids, in red wine than in white wine. Because acetaldehyde and acetaldehyde-albumin complexes have be en implicated in the pathogenesis of alcohol-mediated tissue damage, t hese data suggest that dietary antioxidants may influence the biologic al consequences of excess alcohol consumption.