![]()
|
|
||||||||
J. Biol. Chem., Vol. 279, Issue 8, 6526-6533, February 20, 2004
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||









||
From the
Department of Biochemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada and the ¶Northwest Lipid Research Laboratories, University of Washington, Seattle, Washington 98103
Elevated plasma concentrations of lipoprotein(a) (Lp(a)) are a risk factor for a variety of atherosclerotic disorders including coronary heart disease. In the current study, we report that incubation of cultured human umbilical vein or coronary artery endothelial cells with Lp(a) elicits a dramatic rearrangement of the actin cytoskeleton characterized by increased central stress fiber formation and redistribution of focal adhesions. These effects are mediated by the apolipoprotein(a) (apo(a)) component of Lp(a) since incubation of apo(a) with the cells evoked similar cytoskeletal rearrangements, while incubation with low density lipoprotein had no effect. Apo(a) also produced a time-dependent increase in transendothelial permeability. The cytoskeletal rearrangements evoked by apo(a) were abolished by C3 transferase, which inhibits Rho, and by Y-27632, an inhibitor of Rho kinase. In addition to actin cytoskeleton remodeling, apo(a) was found to cause VE-cadherin disruption and focal adhesion molecule reorganization in a Rho- and Rho kinase-dependent manner. Cell-cell contacts were found to be regulated by Rho and Rac but not Cdc42. Apo(a) caused a transient increase in the extent of myosin light chain phosphorylation. Finally apo(a) did not evoke increases in intracellular calcium levels, although the effects of apo(a) on the cytoskeleton were found to be calcium-dependent. We conclude that the apo(a) component of Lp(a) activates a Rho/Rho kinase-dependent intracellular signaling cascade that results in increased myosin light chain phosphorylation with attendant rearrangements of the actin cytoskeleton. We propose that the resultant increase in endothelial permeability caused by Lp(a) may help explain the atherosclerotic risk posed by elevated concentrations of this lipoprotein.
Received for publication, September 2, 2003 , and in revised form, November 20, 2003.
* This work was supported in part by Heart and Stroke Foundation of Ontario Grants T4844 (to M. L. K.) and T4905 (to G. P. C.) and Program Grant HSPRG 4522. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Supported by a J. D. Schultz Summer Student Scholarship from the Heart and Stroke Foundation of Ontario.
|| To whom correspondence should be addressed: Dept. of Biochemistry, Rm. A208 Botterell Hall, Queen's University, Kingston, Ontario K7L 3N6, Canada. Tel.: 613-533-6586; Fax: 613-533-2987; E-mail: mk11{at}post.queensu.ca.
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
G. P. van Nieuw Amerongen, R. J. P. Musters, E. C. Eringa, P. Sipkema, and V. W. M. van Hinsbergh Thrombin-induced endothelial barrier disruption in intact microvessels: role of RhoA/Rho kinase-myosin phosphatase axis Am J Physiol Cell Physiol, May 1, 2008; 294(5): C1234 - C1241. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Eiselein, D. W. Wilson, M. W. Lame, and J. C. Rutledge Lipolysis products from triglyceride-rich lipoproteins increase endothelial permeability, perturb zonula occludens-1 and F-actin, and induce apoptosis Am J Physiol Heart Circ Physiol, June 1, 2007; 292(6): H2745 - H2753. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Stamatovic, O. B. Dimitrijevic, R. F. Keep, and A. V. Andjelkovic Protein Kinase C{alpha}-RhoA Cross-talk in CCL2-induced Alterations in Brain Endothelial Permeability J. Biol. Chem., March 31, 2006; 281(13): 8379 - 8388. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. H. O'Neil, M. B. Boffa, M. A. Hancock, J. G. Pickering, and M. L. Koschinsky Stimulation of Vascular Smooth Muscle Cell Proliferation and Migration by Apolipoprotein(a) Is Dependent on Inhibition of Transforming Growth Factor-{beta} Activation and on the Presence of Kringle IV Type 9 J. Biol. Chem., December 31, 2004; 279(53): 55187 - 55195. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |