| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
,**,**
* Departments of Internal Medicine, University of Kentucky Medical Center, Lexington, KY 40536
Biochemistry, University of Kentucky Medical Center, Lexington, KY 40536
Gill Heart Institute, University of Kentucky Medical Center, Lexington, KY 40536
** Department of Veterans Affairs Medical Center, Lexington, KY 40511
1 To whom correspondence should be addressed. e-mail: nrwebb1{at}pop.uky.edu
Scavenger receptor BI (SR-BI) is a multi-ligand lipoprotein receptor that mediates selective lipid uptake from HDL, and plays a central role in hepatic HDL metabolism. In this report, we investigated the extent to which SR-BI selective lipid uptake contributes to LDL metabolism. As has been reported for human LDL, mouse SR-BI expressed in transfected cells mediated selective lipid uptake from mouse LDL. However, LDL-cholesteryl oleoyl ester (CE) transfer relative to LDL-CE bound to the cell surface (fractional transfer) was 
18-fold lower compared with HDL-CE. Adenoviral vector-mediated SR-BI overexpression in livers of human apoB transgenic mice (10-fold increased expression) reduced plasma HDL-cholesterol (HDL-C) and apolipoprotein (apo)A-I concentrations to nearly undetectable levels 3 days after adenovirus infusion. Increased hepatic SR-BI expression resulted in only a modest depletion in LDL-C that was restricted to large LDL particles, and no change in steady-state concentrations of human apoB. Kinetic studies showed a 19% increase in the clearance rate of LDL-CE in mice with increased SR-BI expression, but no change in LDL apolipoprotein clearance. Quantification of hepatic uptake of LDL-CE and LDL-apolipoprotein showed selective uptake of LDL-CE in livers of human apo B transgenic mice. However, such uptake was not significantly increased in mice over-expressing SR-BI.
We conclude that SR-BI-mediated selective uptake from LDL plays a minor role in LDL metabolism in vivo.
Abbreviations: CE, cholesteryl oleoyl ester; CEt, cholesteryl oleoyl ether; CHO, Chinese hamster ovary; SR-BI, scavenger receptor class B type I
Supplementary key words scavenger receptor BI • selective uptake • apolipoprotein B • transfected cells • low density lipoprotein receptor • transgenic mice • adenoviral vector
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  M. Van Eck, M. Hoekstra, R. Out, I. S. T. Bos, J. K. Kruijt, R. B. Hildebrand, and T. J. C. Van Berkel Scavenger receptor BI facilitates the metabolism of VLDL lipoproteins in vivo J. Lipid Res., January 1, 2008; 49(1): 136 - 146. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Sun, E. R. M. Eckhardt, S. Shetty, D. R. van der Westhuyzen, and N. R. Webb Quantitative analysis of SR-BI-dependent HDL retroendocytosis in hepatocytes and fibroblasts J. Lipid Res., August 1, 2006; 47(8): 1700 - 1713. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Out, M. Hoekstra, S. C. A. de Jager, P. de Vos, D. R. van der Westhuyzen, N. R. Webb, M. Van Eck, E. A. L. Biessen, and T. J. C. Van Berkel Adenovirus-mediated hepatic overexpression of scavenger receptor class B type I accelerates chylomicron metabolism in C57BL/6J mice J. Lipid Res., June 1, 2005; 46(6): 1172 - 1181. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. R. Brodeur, V. Luangrath, G. Bourret, L. Falstrault, and L. Brissette Physiological importance of SR-BI in the in vivo metabolism of human HDL and LDL in male and female mice J. Lipid Res., April 1, 2005; 46(4): 687 - 696. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. R. Webb, M. C. de Beer, B. F. Asztalos, N. Whitaker, D. R. van der Westhuyzen, and F. C. de Beer Remodeling of HDL remnants generated by scavenger receptor class B type I J. Lipid Res., September 1, 2004; 45(9): 1666 - 1673. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Fu, D. Mukhopadhyay, N. O. Davidson, and J. Borensztajn The Peroxisome Proliferator-activated Receptor {alpha} (PPAR{alpha}) Agonist Ciprofibrate Inhibits Apolipoprotein B mRNA Editing in Low Density Lipoprotein Receptor-deficient Mice: EFFECTS ON PLASMA LIPOPROTEINS AND THE DEVELOPMENT OF ATHEROSCLEROTIC LESIONS J. Biol. Chem., July 2, 2004; 279(27): 28662 - 28669. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Out, J. K. Kruijt, P. C. N. Rensen, R. B. Hildebrand, P. de Vos, M. Van Eck, and T. J. C. Van Berkel Scavenger Receptor BI Plays a Role in Facilitating Chylomicron Metabolism J. Biol. Chem., April 30, 2004; 279(18): 18401 - 18406. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. R. Webb, M. C. de Beer, F. C. de Beer, and D. R. van der Westhuyzen ApoB-containing lipoproteins in apoE-deficient mice are not metabolized by the class B scavenger receptor BI J. Lipid Res., February 1, 2004; 45(2): 272 - 280. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Zhang, P. G. Yancey, Y. R. Su, V. R. Babaev, Y. Zhang, S. Fazio, and M. F. Linton Inactivation of Macrophage Scavenger Receptor Class B Type I Promotes Atherosclerotic Lesion Development in Apolipoprotein E-Deficient Mice Circulation, November 4, 2003; 108(18): 2258 - 2263. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Rigotti, H. E. Miettinen, and M. Krieger The Role of the High-Density Lipoprotein Receptor SR-BI in the Lipid Metabolism of Endocrine and Other Tissues Endocr. Rev., June 1, 2003; 24(3): 357 - 387. [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 |
