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Altered distribution of platelet-activating factor-acetylhydrolase activity between LDL and HDL as a function of the severity of hypercholesterolemia

Altered distribution of platelet-activating factor-acetylhydrolase activity between LDL and HDL as a function of the severity of hypercholesterolemia

Authors :
Vasilis Tsimihodimos
Sonia-Athena P. Karabina
Afroditi P. Tambaki
Eleni Bairaktari
George Miltiadous
John A. Goudevenos
Marios A. Cariolou
M. John Chapman
Alexandros D. Tselepis
Moses Elisaf
Source :
Journal of Lipid Research, Vol 43, Iss 2, Pp 256-263 (2002)
Publication Year :
2002
Publisher :
Elsevier, 2002.

Abstract

Platelet-activating factor-acetylhydrolase (PAF-AH) is a lipoprotein-associated phospholipase A2 capable of hydrolyzing platelet-activating factor (PAF) and oxidatively modified phospholipids. We studied the plasma- and lipoprotein-associated PAF-AH activity in patients with primary hypercholesterolemia. Thirty-eight unrelated patients with heterozygous familial hypercholesterolemia (HeteroFH), five patients with homozygous FH (HomoFH), and 33 patients with primary non-FH hypercholesterolemia (NonFH) participated in the study. In all patient groups the plasma PAF-AH activity was significantly elevated compared with 33 normolipidemic controls, the HomoFH having the highest and the NonFH patients showing the lowest enzyme activity. Gradient ultracentrifugation studies showed that this increase is not only due to the elevation in the plasma LDL but also to the increase in the PAF-AH activity associated with each LDL subfraction, being more profound in the small-dense LDL-5. Unlike LDL, no difference in the HDL-associated PAF-AH activity was observed among all groups. Consequently, an altered distribution of enzyme activity among apolipoprotein B (apoB)- and apolipoprotein A-I (apoA-I)-containing lipoproteins is observed in hypercholesterolemic patients, resulting in a significant decrease in the ratio of the HDL-associated PAF-AH to the total plasma enzyme activity compared with controls. This reduction is proportional to the increase of the plasma LDL-cholesterol (LDL-C) levels and consequently to the severity of the hypercholesterolemia. Thus, the ratio of HDL-associated PAF-AH-total plasma enzyme activity may be useful as a potential marker of atherogenicity in subjects with primary hypercholesterolemia.—Tsimihodimos, V., S-A. P. Karabina, A. P. Tambaki, E. Bairaktari, G. Miltiadous, J. A. Goudevenos, M. A. Cariolou, M. J. Chapman, A. D. Tselepis, and M. Elisaf. Altered distribution of platelet-activating factor-acetylhydrolase activity between LDL and HDL as a function of the severity of hypercholesterolemia.

Details

Language :
English
ISSN :
00222275
Volume :
43
Issue :
2
Database :
Directory of Open Access Journals
Journal :
Journal of Lipid Research
Publication Type :
Academic Journal
Accession number :
edsdoj.365f59849a924c4584b92aa7345135e4
Document Type :
article
Full Text :
https://doi.org/10.1016/S0022-2275(20)30167-X