149 Connective tissue growth factor is the key factor in extracellular matrix protein deposition in myocardial fibrosis development after hypertension derived from angiotensin II exposure

2011 ◽  
Vol 27 (5) ◽  
pp. S116
Author(s):  
N. Rosin ◽  
T. Myers ◽  
T.D. Lee ◽  
J. Légaré
2006 ◽  
Vol 290 (1) ◽  
pp. L153-L161 ◽  
Author(s):  
Janette K. Burgess ◽  
Qi Ge ◽  
Maree H. Poniris ◽  
Sarah Boustany ◽  
Stephen M. Twigg ◽  
...  

Airway remodeling describes the structural changes that occur in the asthmatic airway that include airway smooth muscle hyperplasia, increases in vascularity due to angiogenesis, and thickening of the basement membrane. Our aim in this study was to examine the effect of transforming growth factor-β on the release of connective tissue growth factor and vascular endothelial growth factor from human airway smooth muscle cells derived from asthmatic and nonasthmatic patients. In addition we studied the immunohistochemical localization of these cytokines in the extracellular matrix after stimulating bronchial rings with transforming growth factor-β. Connective tissue growth factor and vascular endothelial growth factor were released from both cell types and colocalized in the surrounding extracellular matrix. Prostaglandin E2 inhibited the increase in connective tissue growth factor mRNA but augmented the release of vascular endothelial growth factor. Matrix metalloproteinase-2 decreased the amount of connective tissue growth factor and vascular endothelial growth factor, but not fibronectin deposited in the extracellular matrix. This report provides the first evidence that connective tissue growth factor may anchor vascular endothelial growth factor to the extracellular matrix and that this deposition is decreased by matrix metalloproteinase-2 and prostaglandin E2. This relationship has the potential to contribute to the changes that constitute airway remodeling, therefore providing a novel focus for therapeutic intervention in asthma.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Toru Tanaka ◽  
Takehisa Shimizu ◽  
Norimichi Koitabashi ◽  
Hiroki Matsui ◽  
Hiroshi Doi ◽  
...  

[Objective] Runx2, a key transcription factor in osteoblast differentiation, is expressed in calcified atherosclerotic plaques. We have recently shown that Runx2 represses vascular smooth muscle cells (VSMCs) differentiation and promotes their osteogenic differentiation. Connective tissue growth factor (CTGF) has been implicated in the progression to vulnerable plaque by inducing mononuclear cell chemotaxis and VSMCs apoptosis despite of its potent stimulatory effect on connective tissue cell the proliferation and extracellular matrix synthesis. To assess the role of Runx2 in the process of plaque development, we investigated the molecular mechanism of the CTGF gene expression by Runx2 in VSMCs. [Methods and Results] RT-PCR analyses showed that adenovirally overexpressed Runx2 significantly repressed the basal expression of the CTGF gene in human aortic SMCs (HASMCs). Consistent with this, knockdown of the Runx2 expression in HASMCs by small interfering RNA (siRNA) increased CTGF mRNA levels. Luciferase assays showed that Runx2 reduced the transcriptional activity of the CTGF promoter. Transfection of a series of 5′-deletion constructs revealed that Runx2 inhibited CTGF expression through the sequence element located at 5′ untranslated region of CTGF mRNA. We next examined the effects of Runx2 on the TGFβ-induced CTGF expression. Runx2 overexpression significantly repressed CTGF expression in HASMCs stimulated with TGFβ, and knockdown of Runx2 by siRNA enhanced the induction of CTGF expression in response to TGFβ. Runx2 repressed TGFβ-induced CTGF promoter activity through the sequence including Smad binding element (SBE). Overexpression of Runx2 significantly reduced TGFβ- and Smad3-mediated luciferase activity of Smad-dependent promoter which contains four copies of SBE. Biotinylated DNA pulldown assay using SBE of CTGF promoter showed that Runx2 formed a complex with Smad3 and Smad4. [Conclusion] Runx2 repressed basal and TGFβ-induced CTGF gene expression in VSMCs. Thus, in addition to the potential for inducing vascular calcification, Runx2 may affect plaque stability by modulating extracellular matrix synthesis through inhibiting CTGF gene expression and TGFβ signaling.


2001 ◽  
Vol 281 (5) ◽  
pp. C1457-C1467 ◽  
Author(s):  
Gaétan Thibault ◽  
Marie-Josée Lacombe ◽  
Lynn M. Schnapp ◽  
Alexandre Lacasse ◽  
Fatiha Bouzeghrane ◽  
...  

Using a novel pharmacological tool with125I-echistatin to detect integrins on the cell, we have observed that cardiac fibroblasts harbor five different RGD-binding integrins: α8β1, α3β1, α5β1, αvβ1, and αvβ3. Stimulation of cardiac fibroblasts by angiotensin II (ANG II) or transforming growth factor-β1 (TGF-β1) resulted in an increase of protein and heightening by 50% of the receptor density of α8β1-integrin. The effect of ANG II was blocked by an AT1, but not an AT2, receptor antagonist, or by an anti-TGF-β1 antibody. ANG II and TGF-β1 increased fibronectin secretion, smooth muscle α-actin synthesis, and formation of actin stress fibers and enhanced attachment of fibroblasts to a fibronectin matrix. The α8- and β1-subunits were colocalized by immunocytochemistry with vinculin or β3-integrin at focal adhesion sites. These results indicate that α8β1-integrin is an abundant integrin on rat cardiac fibroblasts. Its positive modulation by ANG II and TGF-β1 in a myofibroblast-like phenotype suggests the involvement of α8β1-integrin in extracellular matrix protein deposition and cardiac fibroblast adhesion.


Cardiology ◽  
2013 ◽  
Vol 127 (2) ◽  
pp. 114-120 ◽  
Author(s):  
Song Gao ◽  
Tie-wen Liu ◽  
Zhe Wang ◽  
Zhen-yu Jiao ◽  
Jun Cai ◽  
...  

2020 ◽  
Vol 295 (9) ◽  
pp. 2687-2697 ◽  
Author(s):  
Thomas J. Broekelmann ◽  
Nicholas K. Bodmer ◽  
Robert P. Mecham

Microfibril-associated glycoprotein-1 (MAGP-1) is a component of vertebrate extracellular matrix (ECM) microfibrils that, together with the fibrillins, contributes to microfibril function. Many of the phenotypes associated with MAGP-1 gene inactivation are consistent with dysregulation of the transforming growth factor β (TGFβ)/bone morphogenetic protein (BMP) signaling system. We have previously shown that full-length MAGP-1 binds active TGFβ-1 and some BMPs. The work presented here further defines the growth factor–binding domain of MAGP-1. Using recombinant domains and synthetic peptides, along with surface plasmon resonance analysis to measure the kinetics of the MAGP-1–TGFβ-1 interaction, we localized the TGFβ- and BMP-binding site in MAGP-1 to a 19-amino acid–long, highly acidic sequence near the N terminus. This domain was specific for binding active, but not latent, TGFβ-1. Growth factor activity experiments revealed that TGFβ-1 retains signaling activity when complexed with MAGP-1. Furthermore, when bound to fibrillin, MAGP-1 retained the ability to interact with TGFβ-1, and active TGFβ-1 did not bind fibrillin in the absence of MAGP-1. The absence of MAGP was sufficient to raise the amount of total TGFβ stored in the ECM of cultured cells, suggesting that the MAGPs compete with the TGFβ large latent complex for binding to microfibrils. Together, these results indicate that MAGP-1 plays an active role in TGFβ signaling in the ECM.


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