|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||


* Department of Internal Medicine, University of Kentucky Medical Center, Lexington, KY 40536, and Department of Veterans Affairs Medical Center, Lexington, KY, 40511
Department of Medicine, University of California, Los Angeles, CA 90095
Department of Statistics, University of Kentucky, Lexington, KY 40506
1 To whom correspondence should be addressed. e-mail: dvwest1{at}uky.edu
The class B scavenger receptors SR-BI and CD36 exhibit a broad ligand binding specificity. SR-BI is well characterized as a HDL receptor that mediates selective cholesteryl ester uptake from HDL. CD36, a receptor for oxidized LDL, also binds HDL and mediates selective cholesteryl ester uptake, although much less efficiently than SR-BI. Apolipoprotein A-II (apoA-II), the second most abundant HDL protein, is considered to be proatherogenic, but the underlying mechanisms are unclear. We previously showed that apoA-II modulates SR-BI-dependent binding and selective uptake of cholesteryl ester from reconstituted HDL. To investigate the effect of apoA-II in naturally occurring HDL on these processes, we compared HDL without apoA-II (from apoA-II null mice) with HDLs containing differing amounts of apoA-II (from C57BL/6 mice and transgenic mice expressing a mouse apoA-II transgene). The level of apoA-II in HDL was inversely correlated with HDL binding and selective cholesteryl ester uptake by both scavenger receptors, particularly CD36. Interestingly, for HDL lacking apoA-II, the efficiency with which CD36 mediated selective uptake reached a level similar to that of SR-BI.
These results demonstrate that apoA-II exerts a marked effect on HDL binding and selective lipid uptake by the class B scavenger receptors and establishes a potentially important relationship between apoA-II and CD36.
Abbreviations: apoA-II, apolipoprotein A-II; CE, cholesteryl ester; oxLDL, oxidized LDL; POPC, L-
-palmitoyloleoylphosphatidylcholine; rHDL, reconstituted HDL; SR-BI, scavenger receptor class B, type I
Supplementary key words lipoprotein metabolism selective lipid uptake atherosclerosis apolipoprotein A-II high density lipoprotein
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
B. F. Asztalos, M. de la Llera-Moya, G. E. Dallal, K. V. Horvath, E. J. Schaefer, and G. H. Rothblat Differential effects of HDL subpopulations on cellular ABCA1- and SR-BI-mediated cholesterol efflux J. Lipid Res., October 1, 2005; 46(10): 2246 - 2253. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. de Beer, D. van der Westhuyzen, N. L. Whitaker, N. R. Webb, and F. C. de Beer SR-BI-mediated selective lipid uptake segregates apoA-I and apoA-II catabolism J. Lipid Res., October 1, 2005; 46(10): 2143 - 2150. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Rotllan, V. Ribas, L. Calpe-Berdiel, J. M. Martin-Campos, F. Blanco-Vaca, and J. C. Escola-Gil Overexpression of Human Apolipoprotein A-II in Transgenic Mice Does Not Impair Macrophage-Specific Reverse Cholesterol Transport In Vivo Arterioscler. Thromb. Vasc. Biol., September 1, 2005; 25(9): e128 - e132. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. C. Shearer, J. W. Newman, B. D. Hammock, and G. A. Kaysen Graded Effects of Proteinuria on HDL Structure in Nephrotic Rats J. Am. Soc. Nephrol., May 1, 2005; 16(5): 1309 - 1319. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Cai, M. C. de Beer, F. C. de Beer, and D. R. van der Westhuyzen Serum Amyloid A Is a Ligand for Scavenger Receptor Class B Type I and Inhibits High Density Lipoprotein Binding and Selective Lipid Uptake J. Biol. Chem., January 28, 2005; 280(4): 2954 - 2961. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. W. Castellani, P. Gargalovic, M. Febbraio, S. Charugundla, M.-L. Jien, and A. J. Lusis Mechanisms mediating insulin resistance in transgenic mice overexpressing mouse apolipoprotein A-II J. Lipid Res., December 1, 2004; 45(12): 2377 - 2387. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Molecular and Cellular Proteomics | ASBMB Today |