|
Journal of Lipid Research, Vol. 42, 1389-1394, September 2001
Copyright © 2001 by Lipid Research, Inc.
Decreased hepatic accumulation and enhanced esterification of cholesterol in mice deficient in mdr1a and mdr1b P-glycoproteins
Gary D. Lukera,b,
Julie L. Dahlheimera,b,
Richard E. Ostlund, Jr.c, and
David Piwnica-Wormsa,b
a Laboratory of Molecular Radiopharmacology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO 63110
b Mallinckrodt Institute of Radiology, and Department of Molecular Biology and Pharmacology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO 63110
c Division of Endocrinology, Diabetes, and Metabolism, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO 63110
Correspondence to:
David Piwnica-Worms, To whom correspondence should be addressed., piwnica-wormsd{at}mir.wustl.edu (E-mail)
Class I P-glycoproteins [Pgp; MDR1 (ABCB1) in humans, mdr1a and mdr1b in mice] confer resistance to structurally diverse chemotherapeutic drugs in cultured cells and intact animals, but the function of these proteins in normal physiology remains poorly characterized. Based on studies in cell culture, a putative role for class I Pgp in absorption and intracellular trafficking of sterols has been proposed. We examined wild-type and mdr1a-/-/1b-/- mice to determine whether class I Pgp affects cholesterol absorption and esterification in vivo. Using a dual-isotope protocol, absorption of orally administered radiolabeled cholesterol into serum did not differ between wild-type and mdr1a-/-/1b-/- mice, demonstrating that class I Pgp is not essential for overall absorption of cholesterol through the intestine. However, the ratio of oral to intravenous labeled cholesterol in liver was decreased significantly in mdr1a-/-/1b-/- mice. In the liver, but not other tested organs, deletion of class I Pgp enhanced kinetics of esterification of an oral bolus of radiolabeled cholesterol without affecting esterification of cholesterol administered intravenously. Steady-state hepatic content of cholesterol and esterified cholesterol also were unaffected by absence of mdr1a and mdr1b.
Thus, in normal animals, class I Pgp functions to kinetically increase hepatic accumulation and decrease esterification of orally administered cholesterol in vivo. Luker, G. D., J. L. Dahlheimer, R. E. Ostlund, Jr., and D. Piwnica-Worms. Decreased hepatic accumulation and enhanced esterification of cholesterol in mice deficient in mdr1a and mdr1b P-glycoproteins. J. Lipid Res. 2001. 42: 1389;1394.
Supplementary key words:
ATP-binding cassette transporters, multidrug resistance, liver, transgenic animals

CiteULike Complore Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
I. Bottova, A. B. Hehl, S. Stefanic, G. Fabrias, J. Casas, E. Schraner, J. Pieters, and S. Sonda
Host Cell P-glycoprotein Is Essential for Cholesterol Uptake and Replication of Toxoplasma gondii
J. Biol. Chem.,
June 26, 2009;
284(26):
17438 - 17448.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. F. De Rosa, C. Ackerley, B. Wang, S. Ito, D. M. Clarke, and C. Lingwood
Inhibition of Multidrug Resistance by AdamantylGb3, a Globotriaosylceramide Analog
J. Biol. Chem.,
February 22, 2008;
283(8):
4501 - 4511.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
W. Le Goff, M. Settle, D. J. Greene, R. E. Morton, and J. D. Smith
Reevaluation of the role of the multidrug-resistant P-glycoprotein in cellular cholesterol homeostasis
J. Lipid Res.,
January 1, 2006;
47(1):
51 - 58.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. F. De Rosa, D. Sillence, C. Ackerley, and C. Lingwood
Role of Multiple Drug Resistance Protein 1 in Neutral but Not Acidic Glycosphingolipid Biosynthesis
J. Biol. Chem.,
February 27, 2004;
279(9):
7867 - 7876.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2001 by the American Society for Biochemistry and Molecular Biology.
|
Advertisement
Advertisement
|