Articles |
From the Department of Biochemistry, Kyushu University School of Medicine, Fukuoka (D.G., T.O., M.O., M.K.) and Research Institute, Sankyo Company, Shinagawa, Tokyo (H.S., K.A., Y.T.), Japan.
Correspondence to D. Goto, Department of Biochemistry, Kyushu University School of Medicine, Fukuoka 812-82, Japan.
Abstract Gemfibrozil reduces the plasmal levels of cholesterol and triglyceride in patients with hyperlipidemia by a mechanism that is not well understood. The present study evaluated the effect of gemfibrozil on the LDL receptor in human hepatoma cells compared with that of pravastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase. Exposure to gemfibrozil, 40 µmol/L, for 3 days increased the binding of 125I-LDL to the surface of three lines of human hepatoma cell, HepG2, HuH7, and HLE by 1.5- to 2.0-fold. Similar findings were observed with pravastatin. Scatchard analysis with 125I-LDL indicated an increased number of LDL receptors on the cell surface of HepG2 cells when treated with gemfibrozil and pravastatin. However, the gemfibrozil-treated cells exhibited no increase in the binding of 125I-epidermal growth factor (EGF). Gemfibrozil increased the levels of LDL receptor mRNA and protein in HepG2 cells. The increase in LDL receptor activity induced by pravastatin was abolished by concomitant administration of mevalonic acid, 770 µmol/L. This effect was not seen with gemfibrozil, suggesting the mechanism differs for the two lipid-lowering drugs. To determine whether this increase in mRNA was due to transcriptional activation, we prepared HepG2 cells transfected with an LDL receptor promoter-reporter construct that contained a sterol regulatory element. The expression of LDL receptor regulated by the sterol regulatory element was increased by pravastatin, but not by gemfibrozil. We evaluated the stability of the mRNA in the presence of actinomycin D to explain the increase in the LDL receptor mRNA. Gemfibrozil prolonged the half-life of the mRNA for LDL receptor but not that for the EGF receptor. Stabilization of the LDL receptor mRNA is suggested to be the novel mode of action of gemfibrozil.
Key Words: gemfibrozil pravastatin low density lipoprotein receptor mRNA stability
This article has been cited by other articles:
![]() |
S. Kourimate, C. Le May, C. Langhi, A. L. Jarnoux, K. Ouguerram, Y. Zair, P. Nguyen, M. Krempf, B. Cariou, and P. Costet Dual Mechanisms for the Fibrate-mediated Repression of Proprotein Convertase Subtilisin/Kexin Type 9 J. Biol. Chem., April 11, 2008; 283(15): 9666 - 9673. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Abidi, Y. Zhou, J.-D. Jiang, and J. Liu Extracellular Signal-Regulated Kinase-Dependent Stabilization of Hepatic Low-Density Lipoprotein Receptor mRNA by Herbal Medicine Berberine Arterioscler Thromb Vasc Biol, October 1, 2005; 25(10): 2170 - 2176. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Post, H. Duez, P. P. Gervois, B. Staels, F. Kuipers, and H. M.G. Princen Fibrates Suppress Bile Acid Synthesis via Peroxisome Proliferator-Activated Receptor-{alpha}-Mediated Downregulation of Cholesterol 7{alpha}-Hydroxylase and Sterol 27-Hydroxylase Expression Arterioscler Thromb Vasc Biol, November 1, 2001; 21(11): 1840 - 1845. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. D. Santos, L. I. Ventura, A. C. Sposito, R. Schreiber, J. A.F. Ramires, and R. C. Maranhao The effects of gemfibrozil upon the metabolism of chylomicron-like emulsions in patients with endogenous hypertriglyceridemia Cardiovasc Res, February 1, 2001; 49(2): 456 - 465. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Knouff, S. Malloy, J. Wilder, M. K. Altenburg, and N. Maeda Doubling Expression of the Low Density Lipoprotein Receptor by Truncation of the 3'-Untranslated Region Sequence Ameliorates Type III Hyperlipoproteinemia in Mice Expressing the Human ApoE2 Isoform J. Biol. Chem., February 2, 2001; 276(6): 3856 - 3862. [Abstract] [Full Text] [PDF] |
||||
|
ATVB Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1997 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |