HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jialal, I. Articles by Chait, A. Search for Related Content PubMed PubMed Citation Articles by Jialal, I. Articles by Chait, A. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol 30, 1561-1568, Copyright © 1989 by Lipid Research, Inc.

ARTICLES

Differences in the metabolism of oxidatively modified low density lipoprotein and acetylated low density lipoprotein by human endothelial cells: inhibition of cholesterol esterification by oxidatively modified low density lipoprotein

I Jialal and A Chait
Department of Medicine, University of Washington, Seattle 98195.

The rate of degradation of oxidatively modified low density lipoprotein (Ox-LDL) by human endothelial cells was similar to that of unmodified low density lipoprotein (LDL), and was approximately 2-fold greater than the rate of degradation of acetylated LDL (Ac-LDL). While LDL and Ac-LDL both stimulated cholesterol esterification in endothelial cells, Ox-LDL inhibited cholesterol esterification by 34%, demonstrating a dissociation between the degradation of Ox-LDL and its ability to stimulate cholesterol esterification. Further, while LDL and Ac-LDL resulted in a 5- and 15-fold increase in cholesteryl ester accumulation, respectively, Ox-LDL caused only a 1.3-fold increase in cholesteryl ester mass. These differences could be accounted for, in part, by the reduced cholesteryl ester content of Ox-LDL. However, when endothelial cells were incubated with Ac-LDL in the presence and absence of Ox-LDL, Ox-LDL led to a dose-dependent inhibition of cholesterol esterification without affecting the degradation of Ac-LDL. This inhibitory effect of Ox-LDL on cholesteryl ester synthesis was also manifest in normal human skin fibroblasts incubated with LDL and in LDL-receptor-negative fibroblasts incubated with unesterified cholesterol to stimulate cholesterol esterification. Further, the lipid extract from Ox-LDL inhibited cholesterol esterification in LDL- receptor negative fibroblasts. These findings suggest that the inhibition of cholesterol esterification by oxidized LDL is independent of the LDL and scavenger receptors and may be a result of translocation of a lipid component of oxidatively modified LDL across the cell membrane.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				H. Du, S. Schiavi, N. Wan, M. Levine, D. P. Witte, and G. A. Grabowski Reduction of Atherosclerotic Plaques by Lysosomal Acid Lipase Supplementation Arterioscler. Thromb. Vasc. Biol., January 1, 2004; 24(1): 147 - 154. [Abstract] [Full Text] [PDF]

				S. Devaraj, I. Hugou, and I. Jialal {{alpha}}-Tocopherol decreases CD36 expression in human monocyte-derived macrophages J. Lipid Res., April 1, 2001; 42(4): 521 - 527. [Abstract] [Full Text]

				A. J. Brown, E. L. Mander, I. C. Gelissen, L. Kritharides, R. T. Dean, and W. Jessup Cholesterol and oxysterol metabolism and subcellular distribution in macrophage foam cells: accumulation of oxidized esters in lysosomes J. Lipid Res., February 1, 2000; 41(2): 226 - 237. [Abstract] [Full Text]

				P. G. Yancey and W. G. Jerome Lysosomal sequestration of free and esterified cholesterol from oxidized low density lipoprotein in macrophages of different species J. Lipid Res., July 1, 1998; 39(7): 1349 - 1361. [Abstract] [Full Text]

				W. G. Jerome, C. Cash, R. Webber, R. Horton, and P. G. Yancey Lysosomal lipid accumulation from oxidized low density lipoprotein is correlated with hypertrophy of the Golgi apparatus and trans-Golgi network J. Lipid Res., July 1, 1998; 39(7): 1362 - 1371. [Abstract] [Full Text]

				L. Kritharides, W. Jessup, E. L. Mander, and R. T. Dean Apolipoprotein A-I–Mediated Efflux of Sterols From Oxidized LDL–Loaded Macrophages Arterioscler. Thromb. Vasc. Biol., February 1, 1995; 15(2): 276 - 289. [Abstract] [Full Text]