scholarly journals Thrombin induced connective tissue growth factor expression in rat vascular smooth muscle cells via the PAR-1/JNK/AP-1 pathway

2012 ◽  
Vol 33 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Wen-chin Ko ◽  
Bing-chang Chen ◽  
Ming-jen Hsu ◽  
Chia-ti Tsai ◽  
Chuang-ye Hong ◽  
...  
2020 ◽  
Vol 10 (23) ◽  
pp. 8729
Author(s):  
Wen-Chin Ko ◽  
Chia-Ti Tsai ◽  
Kai-Cheng Hsu ◽  
Yu-Che Cheng ◽  
Tony Eight Lin ◽  
...  

Restenosis and destructive vascular remodeling are the main reasons for treatment failure in patients undergoing percutaneous coronary intervention (PCI). In this study, we explored the efficacy of magnolol (a traditional Chinese medicine) in the treatment of restenosis. The results of this study showed that the activities of thrombin and PAR-1 (protease-activated receptor 1) were significantly decreased by the treatment of magnolol. Based on protein docking analysis, magnolol exhibits its potential to bind to the PAR-1 active site. In addition, thrombin-induced connective tissue growth factor (CTGF) expression and the upstream of CTGF such as JNK-1 (but not JNK-2), c-Jun, and AP-1 were distinctly inhibited by magnolol (50 μM) in vascular smooth muscle cells (VSMC). For the functional assay, magnolol (50 μM) significantly inhibited the migration of VSMC, and rats treated with magnolol (13 mg/kg/day) after balloon angioplasty has observed a significant reduction in the formation of common arterial neointima. In conclusion, we identified a novel mechanism by which magnolol acts as the thrombin activity inhibitor and may be the PAR-1 antagonist. In accordance with these functions, magnolol could decrease thrombin-induced CTGF expression in VSMCs via PAR-1/JNK-1/AP-1 signaling.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Yoshiaki Ohyama ◽  
Toru Tanaka ◽  
Takehisa Shimizu ◽  
Hiroko Sato ◽  
Norimichi Koitabashi ◽  
...  

[Background] Runx2, a key transcription factor for osteoblastic differentiation, is expressed in calcified atherosclerotic plaques. We recently reported that Runx2 represses vascular smooth muscle cells (VSMC) differentiation and promotes its osteogenic differentiation. Connective tissue growth factor (CTGF) has been implicated in the progression to vulnerable plaque by inducing mononuclear cell chemotaxis and VSMC apoptosis despite of its potent stimulatory effect on synthesis of extracellular matrix. In this study, we investigated the regulatory mechanism of CTGF gene expression by Runx2 in VSMC. [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 attenuated the TGFβ-mediated induction of CTGF expression in HASMCs, 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 containing Smad binding element (SBE), and luciferase assay using SBE-specific mutation construct showed that Runx2 repressed CTGF promoter activity in an SBE-dependent manner. Overexpression of Runx2 significantly reduced TGFβ and Smad3-mediated luciferase activity of 4xSBE-tkLuc, which contains four copies of SBE. Co-immunoprecipitation showed that Runx2 formed a complex with Smad4. [Conclusion] These data demonstrate that Runx2 represses basal and TGFβ-induced CTGF gene expression in VSMC, and thus suggest that besides the potential for inducing vascular calcification, Runx2 may affect plaque stability by modulating extracellular matrix synthesis through inhibiting CTGF gene expression and TGFβ signaling.


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