title: Ethanol withdrawal increases glutathione adducts of 4-hydroxy-2-hexenal but not 4-hydroxyl-2-nonenal in the rat cerebral cortex.
abstract: Ethanol withdrawal increases lipid peroxidation of the polyunsaturated fatty acid (PUFA) docosahexaenoate (22:6; n-3) in the CNS. To further define the role of oxidative damage of PUFAs during ethanol withdrawal, we measured the levels of glutathione adducts of 4-hydroxy-2-hexenal (GSHHE) and 4-hydroxy-2-nonenal (GSHNE) as biomarkers of brain lipid peroxidation of n-3 and n-6 PUFAs, respectively. In this study rats received an ethanol-containing diet for 6 weeks followed by withdrawal ranging from 0 to 7 days. GSHHE content was elevated (>350%) in the cerebral cortex after 2 days of withdrawal with no change in GSHNE. The levels of GSHHE were significantly greater (2- to 20-fold) than those of GSHNE in multiple brain regions. Experiments demonstrated that intoxication and withdrawal did not alter the enzymatic rate of formation of GSHHE or GSHNE, but the rate of formation of GSHHE was higher (approximately 50%) than that of GSHNE. These results indicate that selective oxidative damage to n-3 PUFAs occurs in the cerebral cortex as a result of ethanol withdrawal and that 4-hydroxy-2-hexenal is metabolized to the GSH adduct more efficiently than HNE.
authors.affiliation: Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota, Grand Forks, ND 58203-9037, USA.
authors.forename: Eric K
authors.initials: EK
authors.lastname: Long
authors.forename: Thad A
authors.initials: TA
authors.lastname: Rosenberger
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Picklo
mesh_terms: D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism*; D002853:Chromatography, Liquid; D000431:Ethanol / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D005978:Glutathione / Q000737:chemistry* / Q000378:metabolism*; D015227:Lipid Peroxidation; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000447:Aldehydes; D005227:Fatty Acids; C045934:4-hydroxy-2-hexenal; D000431:Ethanol; D005978:Glutathione; C027576:4-hydroxy-2-nonenal