E. Waddington et al., Identification and quantitation of unique fatty acid oxidation products inhuman atherosclerotic plaque using high-performance liquid chromatography, ANALYT BIOC, 292(2), 2001, pp. 234-244
Oxidation of lipoproteins, particularly low-density lipoprotein, is thought
to play a major role in the development of atherosclerosis, We set out to
identify and quantitate the major fatty acid oxidation products in human at
herosclerotic plaque obtained from individuals undergoing carotid endartere
ctomy. Oxidized lipids were extracted from plaque homogenate under conditio
ns to prevent artifactual oxidation, Identification and quantitation was pe
rformed using HPLC and GC-MS, High levels of hydroxyoctadecanoic acids (0.5
1 +/- 0.17 ng/mug of linoleic acid), 15-hydroxyeicosatetranoic acid (HETE)
(0.66 +/- 0.24 ng/mug of arachidonic acid), and 11-HETE (0.84 +/- 0.24 ng/m
ug of arachidonic acid) were detected in all atherosclerotic plaques (n = 1
0), Low levels of 9-oxo-octadecanoic acid (oxoODE) (0.04 +/- 0.01 ng/mug of
linoleic acid), were present in all samples, while 13-oxoODE (0.01 +/- 0.0
08 ng/mug of linoleic acid) was present in only 4 of the 10 plaque samples.
Of interest was the identification of two previously unidentified compound
s in atherosclerotic plaque, 11-oxo-eicosatetranoic acid in 9 of the 10 sam
ples and 5,6-dihydroxyeicosatetranoic acid in 3 samples. Chiral analysis re
vealed that all the major compounds identified in this study are of a nonen
zymatic origin. This study is the first to provide a convenient HPLC method
to quantify all the products of both linoleic acid and arachidonic acid ox
idation in human atherosclerotic plaque. The quantitation of lipid peroxida
tion products in plaque may be important given the potential biological act
ivity of these compounds and their possible relationship to plaque pathogen
esis and instability. (C) 2001 Academic Press.