FATTY-ACID COMPOSITION OF MICROSOMAL PHOSPHOLIPIDS IN RATS FED DIFFERENT OILS AND ANTIOXIDANT VITAMINS SUPPLEMENT

The aim of the study was to examine effects of feeding diets containin g different oils and antioxidant vitamins supplementation of the fatty acid composition of hepatic microsomal phospholipids in the rat. Fort y-eight male Sprague Dawley rats were fed for 20 days diets containing 15% corn, olive, fish, or hazelnut oil, without or with the addition of beta-carotene (30 mg/kg) and dl-alpha-tocopherylacetate (500 mg/kg) , n = 6 per group. Microsomal phospholipids of rats fed corn oil exhib ited higher content of linoleic, arachidonic,and docosatetraenoic acid s (P < 0.05). Compared with corn oil (control group), olive oil intake increased palmitic, oleic,and vaccenic acids in phosphatidylcholine a nd phosphatidylserine + phosphatidylinositol, and vaccenic acid in pho sphatidylethanolamine (P < 0.05). Fish oil intake increased the level of n-3 long-chain polyunsaturated fatty acids,and decreased arachidoni c acid in all phospholipids (P < 0.05). ON the other hand, the intake of hazelnut oil increased palmitoleic and oleic acids in phosphatidylc holine and phosphatidylethanolamine, and palmitoleic and vaccenic acid s in phosphatidylserine + phosphatidylinositol (P < 0.05). Vitamin sup plementation increased microsomal retinol in rats fed corn oil, and al pha-tocopherol in all groups fed vegetable oils P < 0.05). The intake of vitamins supplement induced slight modifications of the fatty acid profile of microsomal phospholipids: a higher level of monounsaturated fatty acids, mainly oleic acid, with a reduction of polyunsaturated f atty acids was observed. These results manifest that the composition o f microsomes is affected by the fatty acid profile of dietary oils and the intake of antioxidant vitamins supplements. (C) Elsevier Science Inc. 1998.