Journal of Lipid Research, Vol 30, 59-64, Copyright © 1989 by Lipid Research, Inc.
Effect of dietary supplementation with a fish oil concentrate on the alkenylacyl class of ethanolamine phospholipid in human platelets
HM Aukema and BJ Holub
Department of Nutritional Sciences, University of Guelph, Ontario, Canada.
It has been demonstrated that the alkenylacyl class of ethanolamine
phospholipid (PE) represents one of the major forms of eicosapentaenoic
acid (EPA)-containing phospholipid in the circulating platelets isolated
from human subjects consuming a fish oil concentrate. Since the alkenylacyl
PE from human platelets is enriched in the eicosanoid precursor arachidonic
acid (AA) and the n-6 polyunsaturate adrenic acid (AdA), it was of interest
to study changes in alkenylacyl PE fatty acid composition upon fish oil
supplementation. Healthy volunteers were given 20 capsules of MaxEPA daily
(3.6 g of EPA plus 2.4 g of docosahexaenoic acid, DHA) for 6 weeks followed
by a 6-week recovery period. Washed platelet suspensions were prepared and
the fatty acid compositions of the phospholipid components were evaluated
by thin- layer and gas-liquid chromatography at weeks 0, 3, 6, 9, and 12.
Fatty acid composition changes were more pronounced in the alkenylacyl PE
than in other platelet phospholipids as a result of fish oil consumption.
The alkenylacyl PE exhibited a greater drop (by 20.3 mol%, i.e., from 72.0
to 51.7 mol%) in AA than diacyl PE (by 1.6 mol%) or total (predominantly
diacyl) choline phospholipids (PC) (by 4.5 mol%). In alkenylacyl PE, the
predominant reservoir of AdA in human platelet phospholipid, a dramatic
reduction in the level of AdA also resulted with MaxEPA supplementation
(from 7.9 to 3.1 mol%); diacyl PE and total PC decreased by 0.6 and 0.3
mol%, respectively. With respect to the n-3 fatty acids, EPA rose by 12.5
mol% in alkenylacyl PE, compared to only 3.8 and 2.5 mol% in diacyl PE and
total PC, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)