Modulation of brain lipids of rats by various dietary oils: Sunflower, high-oleic sunflower, olive, rapeseed or coriander oil

Feeding oils containing various proportions of the monounsaturated oleic (1 8:1 n-9) and petroselinic (18:1 n-!2) acids to rats was found to strongly a ffect the levels of arachidonate (AA, 20:4 n-6) [J Nutr 1995;125: 1563-1568 ; Nutr Res 1997; 17: 89-97] and docosahexaenoate (DHA, 22:6 n-3) [Nutr Res 1998; 18: 851-861] in liver and heart. In continuation of the above studies the pattern of long-chain polyunsaturated fatty acids (LC-PUFA) in brain l ipids was examined in male Wistar rats that were fed isocaloric diets conta ining 120 g/kg diet of conventional low-oleic sunflower oil (SF), high-olei c sunflower (HOS) and olive oils (OLI), medium-oleic Canola-type rapeseed o il (RAP) and high-petroselinic coriander oil (COR) for 10 wk. In the total lipids of brain the proportion of DHA was significantly higher after feedin g OLI and RAP as compared to SF and COR. In phosphatidylethanolamines (PE) and phosphatidylcholines (PC) the proportion of DHA was significantly highe r after feeding RAP as compared to SF and COR, which is attributed to a rel atively high level of alpha-linolenic acid in RAP. The proportion of AA and other n-6 LC-PUFA in both PE and PC was significantly lower after feeding COR than each of the other diets, which is envisaged to be caused by the pr esence in COR of high proportion of petroselinic acid having a Delta(6)-dou ble bond that inhibits the Delta(6)-desaturase as a pseudo-product by mimic king the structure of 18:3 n-6, a precursor of AA. Some dietary oil-mediate d alteration in the proportions of lignoceric (24:0) and nervonic (24:1) ac ids was observed in the sphingomyelins (SM) of brain. (C) 1999 Elsevier Sci ence Inc.