EFFECT OF METHIONINE ON THE FATTY ACID COMPOSITION OF CELLULAR MEMBRANES IN RATS WITH CHRONIC ETHANOL CONSUMPTION AND JEJUNOILEAL BYPASS

The objective of this study was to investigate the effect ofalcohol administration on jejunoileal bypass (JIB)-induced liverdysfunction in rats resulting in abnormalities of fatty acidcomposition of cell membranes, and whether methionine is ableto reverse these changes. Male Wistar rats were subjected toa jejunoileal bypass operation. For 12 weeks, all groups werepair-fed either an alcohol-containing (36% of total calories)liquid diet or a liquid diet in which alcohol was replaced isocaloricallyby starch. Methionine supplementation in three control groupswas 0, 32 and 160 mg/kg body weight/day and the rats in thefour alcohol feeding groups received 0, 32, 160 and 224 mg/kgbody weight/day. In the alcohol group without any methioninesupplementation, higher proportions of oleic and linoleic acidand lower proportions of docosahexaenoic and arachidonic acidbecame evident in tissue samples of liver and jejunum, in comparisonwith the other alcohol group A possible explanation for thisreduction in tissue polyunsaturated fatty acid (PUFA) may bea decrease in the activities of 6-and 5-desaturases, and subsequentlya displacement of PUFA from lipid fractions by other fatty acids.Interestingly, in the alcohol group with the highest methioninesupplementation, compared to all other alcohol groups, lowerproportions of oleic acid, and higher proportions of docosahexaenoicacid, appeared. A possible explanation for this increase ofPUFA in tissue may be increased activities of 6-and 5-desaturases.