Potentiation of ethanol-induced lipid peroxidation of biological membranes by vitamin C.
The hydroxyl free radical (.OH) was generated by the system of ADP-Fe++ and H2O2, trapped by 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and analyzed by electron spin resonance (ESR) spectroscopy. The addition of vitamin C to the system decreased considerably the amount of hydroxyl adduct of DMPO formed. In the presence of ethanol, the ESR spectrum observed was a composite signal of the hydroxyl and hydroxyethyl (HE) adducts of DMPO. However, in the presence of vitamin C and ethanol, pure HE adduct of DMPO was detected. We also detected the increase in lipid peroxidation in the presence of ethanol and vitamin C. These data lead us to hypothesize that in the biological system, formation of these long-lived HE free radicals may result in membrane damage due to an increase in lipid peroxidation.
Ahmad
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Sinclair Comparative Medicine Research Farm, University of Missouri, Columbia 65203-9497.
Cowan
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Sun
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D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D004357:Drug Synergism; D004578:Electron Spin Resonance Spectroscopy; D000431:Ethanol / Q000494:pharmacology*; D005609:Free Radicals; D008054:Lipid Peroxides / Q000378:metabolism*; D008315:Malondialdehyde / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism; D008861:Microsomes / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344
D005609:Free Radicals; D008054:Lipid Peroxides; D008563:Membrane Lipids; D000431:Ethanol; D008315:Malondialdehyde; D001205:Ascorbic Acid