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Updated: Aug 15, 2026

Molecular Analysis of Endothelial-mesenchymal Transition Induced by Transforming Growth Factor-β Signaling
07:49

Molecular Analysis of Endothelial-mesenchymal Transition Induced by Transforming Growth Factor-β Signaling

Published on: August 3, 2018

Antagonism of transforming growth factor-Beta signaling inhibits fibrosis-related genes

Xing-Jun Liu1, Cheng-Mai Ruan, Xian-Feng Gong

  • 1Protein & Peptide Pharmaceutical Laboratory, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China.

Biotechnology Letters
|October 26, 2005
PubMed

Insights

SB-431542 and Smad3 siRNA effectively inhibit fibrosis-related gene expression. These compounds show promise as potential therapeutics for fibrotic diseases by targeting the transforming growth factor-beta1/Smad3 pathway.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Pharmacology

Background:

  • The transforming growth factor-beta1 (TGF-beta1)/Smad3 signaling pathway is crucial in the fibrotic process.
  • Identifying antagonists of this pathway is key to developing anti-fibrotic therapies.

Purpose of the Study:

  • To screen for antagonists of TGF-beta1/Smad3 signaling.
  • To investigate the effects of identified antagonists on fibrosis-related genes.

Main Methods:

  • Construction of a molecular model utilizing a luciferase reporter gene.
  • Dose-dependent suppression assays using SB-431542 and Smad3 small interference RNA (siRNA).
  • Quantitative analysis of plasminogen activator inhibitor-type 1 (PAI-1) and type I collagenalpha1 (Col Ialpha1) gene expression in rat hepatic stellate cells.

Main Results:

  • Both SB-431542 and Smad3 siRNA demonstrated dose-dependent suppression of the reporter gene.
  • Significant inhibition of PAI-1 and Col Ialpha1 gene expression was observed with both SB-431542 and Smad3 siRNA.
  • These effects were validated in rat hepatic stellate cells.

Conclusions:

  • SB-431542 and Smad3 siRNA are effective inhibitors of TGF-beta1/Smad3 signaling.
  • These compounds significantly reduce the expression of key fibrosis-associated genes.
  • SB-431542 and Smad3/siRNA represent potential therapeutic agents for treating fibrotic conditions.

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