|
|
|
|
Deutsches Herzzentrum (D.Z., T.G.N., A.E.M., R.S., K.D., A.S.) and Institut für Pathologie (T.R.), Technische Universität München, Munich, Germany; Micromet AG, Munich, Germany (P.A.B.); Herz-Zentrum, Bad Krozingen, Germany (F.-J.N.); and Indiana Center for Vascular Biology & Medicine, Indianapolis, Indiana (M.A.C.)
Neointima formation, the leading cause of restenosis, is caused by proliferation of coronary artery smooth muscle cells (CASMCs) and is associated with infiltration by monocytes. Rapamycin inhibits neointima formation after stent implantation in humans. It reduces proliferation by its effects on mammalian target of rapamycin (mTOR) kinase. In this study, we investigated the expression of mTOR in human neointima and the effect of rapamycin on global transcriptional events controlling CASMC phenotype. In neointimal CASMCs, mTOR exhibited increased phosphorylation and was translocated to the nucleus compared with control. Comparative gene expression analysis of CASMCs treated with rapamycin (100 ng/ml) revealed down-regulation of the transcription factor E2F-1, a key regulator of G1/S-phase entry, and of various retinoblastoma protein/E2F-1-regulated genes. In addition, we found changes in the expression of genes associated with replication, apoptosis, and extracellular matrix formation. Furthermore, rapamycin decreased the gene expression of endothelial monocyte-activating polypeptide-II (EMAP-II). This decrease of EMAP-II expression was reflected in a reduced adhesiveness of CASMCs for monocytic cells. Addition of EMAP-II counteracted the antiadhesive effect of rapamycin. Therefore, EMAP-II may comprise a mechanism of rapamycin-mediated reduction of the proinflammatory activation of CASMCs. The effects reported here of rapamycin on the down-regulation of genes involved in cell cycle progression, apoptosis, proliferation, and extracellular matrix formation in CASMCs provide an explanation of how rapamycin reduces CASMC proliferation. In addition, rapamycin may contribute to a reduction of inflammatory responses by reducing the adhesiveness of CASMC, a mechanism suggested to be mediated by the production and release of EMAP II.
Received May 16, 2003; accepted January 6, 2004.
Address correspondence to: Dr. Dietlind Zohlnhöfer, Deutsches Herzzentrum, Lazarettstr. 36, D-80636 München, Germany. E-mail: zohlnhoefer{at}dhm.mhn.de
This article has been cited by other articles:
![]() |
J. B.K. Schwarz, N. Langwieser, N. N. Langwieser, M. J. Bek, S. Seidl, H.-H. Eckstein, B. Lu, A. Schomig, H. Pavenstadt, and D. Zohlnhofer Novel Role of the CXC Chemokine Receptor 3 in Inflammatory Response to Arterial Injury: Involvement of mTORC1 Circ. Res., January 30, 2009; 104(2): 189 - 200. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. K. Reddy, J. K. Vasir, S. K. Sahoo, T. K. Jain, M. M. Yallapu, and V. Labhasetwar Inhibition of Apoptosis Through Localized Delivery of Rapamycin-Loaded Nanoparticles Prevented Neointimal Hyperplasia and Reendothelialized Injured Artery Circ Cardiovasc Interv, December 1, 2008; 1(3): 209 - 216. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Tang, Y. Wang, Y. Fan, Y. Zhu, S. Chien, and N. Wang Suppression of c-Cbl Tyrosine Phosphorylation Inhibits Neointimal Formation in Balloon-Injured Rat Arteries Circulation, August 12, 2008; 118(7): 764 - 772. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. G. Nuhrenberg, N. Langwieser, J. B.K. Schwarz, Y. Hou, P. Frank, F. Sorge, S. Matschurat, S. Seidl, A. Kastrati, A. Schomig, et al. EMAP-II downregulation contributes to the beneficial effects of rapamycin after vascular injury Cardiovasc Res, February 1, 2008; 77(3): 580 - 589. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Wang, Y. Bai, L. Qin, P. Zhang, T. Yi, S. A. Teesdale, L. Zhao, J. S. Pober, and G. Tellides Interferon-{gamma} Induces Human Vascular Smooth Muscle Cell Proliferation and Intimal Expansion by Phosphatidylinositol 3-Kinase Dependent Mammalian Target of Rapamycin Raptor Complex 1 Activation Circ. Res., September 14, 2007; 101(6): 560 - 569. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. K. Reddy, J. K. Vasir, G. V. Hegde, S. S. Joshi, and V. Labhasetwar Erythropoietin Induces Excessive Neointima Formation: A Study in a Rat Carotid Artery Model of Vascular Injury Journal of Cardiovascular Pharmacology and Therapeutics, September 1, 2007; 12(3): 237 - 247. [Abstract] [PDF] |
||||
![]() |
T. Raj, P. Kanellakis, G. Pomilio, G. Jennings, A. Bobik, and A. Agrotis Inhibition of Fibroblast Growth Factor Receptor Signaling Attenuates Atherosclerosis in Apolipoprotein E-Deficient Mice Arterioscler Thromb Vasc Biol, August 1, 2006; 26(8): 1845 - 1851. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Rosner, N. McCarthy, and M. Bennett Rapamycin inhibits human in stent restenosis vascular smooth muscle cells independently of pRB phosphorylation and p53 Cardiovasc Res, June 1, 2005; 66(3): 601 - 610. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. I. Rotmans, P. M.T. Pattynama, H. J.M. Verhagen, I. Hino, E. Velema, G. Pasterkamp, and E. S.G. Stroes Sirolimus-Eluting Stents to Abolish Intimal Hyperplasia and Improve Flow in Porcine Arteriovenous Grafts: A 4-Week Follow-Up Study Circulation, March 29, 2005; 111(12): 1537 - 1542. [Abstract] [Full Text] [PDF] |
||||