Cholesterol efflux by acute-phase high density lipoprotein: role of lecithin : cholesterol acyltransferase

Citation
W. Khovidhunkit et al., Cholesterol efflux by acute-phase high density lipoprotein: role of lecithin : cholesterol acyltransferase, J LIPID RES, 42(6), 2001, pp. 967-975
Citations number
48
Categorie Soggetti
Biochemistry & Biophysics
Journal title
JOURNAL OF LIPID RESEARCH
ISSN journal
00222275 → ACNP
Volume
42
Issue
6
Year of publication
2001
Pages
967 - 975
Database
ISI
SICI code
0022-2275(200106)42:6<967:CEBAHD>2.0.ZU;2-H
Abstract
HDL plays an initial role in reverse cholesterol transport by mediating cho lesterol removal from cells, During; infection and inflammation, several ch anges in HDL composition occur that may affect the function of HDL; therefo re, we determined the ability of acute-phase HDL to prc,mote cholesterol re moval from cells. Acute-phase HDL was isolated from plasma of Syrian hamste rs injected with lipopolysaccharide. Cholesterol removal from J774 murine m acrophages by acute-phase HDL was less efficient than that by control HDL b ecause of both a decrease in cholesterol efflux and an increase in choleste rol influx, LCAT activity of acute-phase HDL was significantly lower than t hat of control HDL, When LCAT activity of control HDL was inactivated, chol esterol efflux decreased and cholesterol influx increased to the level obse rved in acute-phase HDL, Inactivation of LCAT had little effect on acute-ph ase HDL, In GM 3468A human fibroblasts, the ability of acute-phase HDL to r emove cholesterol from cells Tvas also lower than that of normal HDL, The i mpaired cholesterol removal, however, was primarily a result of an increase in cholesterol influx without changes in cholesterol efflux, When control HDL in which LCAT had been inactivated was incubated with fibroblasts, chol esterol influx increased to a level comparable to th;lt of acute-phase HDL, without any change in cholesterol efflux. These results suggest that the a bility of acute-phase HDL to mediate cholesterol removal was impaired compa red with that of control HDL and the lower LCAT activity in acute-phase HDL may be responsible for this impairment, The decreased ability of acute-pha se HDL to remove cholesterol from cells may be one of the mechanisms that a ccount for the well-known relationship between infection/inflammation and a therosclerosis. - Khovidhunkit, W., J. K. Shigenaga, A. H. Moser, K. R. Fei ngold, and C. Grunfeld. Cholesterol efflux by acute-phase high density lipo protein: role of lecithin:cholesterol acyltransferase.