[Effect of TGF-beta1 stimulation on the smad signal transduction pathway of human peritoneal mesothelial cells]
Related Experiment Video
Updated: Aug 16, 2026
Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
Published on: October 27, 2020
Hao Zhang1, Fu-You Liu, Ying-Hong Liu
1Department of Nephrology, Third Xiangya Hospital, Central South University, Changsha 410013, China. zhanghaoliaoqing@163.com
Objective:
To explore whether the Smad signal transduction pathway in human peritoneal mesothelial cells (HPMCs) influences the process of human peritoneal fibrosis stimulated by TGF-beta1.
Methods:
HPMCs were isolated from normal human omentum and 95% of the primary cultured cells was confirmed to be HPMCs. The third generation of cultured cells was stimulated by 5 ng/ml TGF-beta1. Immunohistochemistry, Western blotting, ELISA, and RT-PCR were employed to investigate the follows: the protein expression of p-Smad2/3 and its migration in HPMCs; the protein and mRNA expressions of SMAD 7 in cells; and the expressions of extracellular fibronectin (FN) protein, intracellular FN mRNA, as well as intracellular collenge-I (COL1) protein and mRNA.
Results:
The protein expression of p-Smad2/3 in HPMCs obviously increased 15 min (29% p-Smad2/3-positive cells) after TGF-beta1 stimulation, peaking from 30 min (81% ) to 1 h (84%) and dropping after 2 h (37%); Meanwhile, p-Smad2/3 mainly distributed in cytoplasm at 15 min, concentrated in cell nucleus and peri-nucleus from 30 min to 1 h, and distributed in cytoplasm again at 2 h. The protein expression of SMAD7 in cells obviously increased 24 h after TGF-beta1 stimulation, peaking at 48 h. The mRNA expression of SMAD7 time-dependently increased. The expressions of extracellular FN protein, intracellular FN mRNA, as well as intracellular COL1 protein and mRNA significantly increased and all of them displayed time dependency.
Conclusion:
The SMAD signal transduction pathway of HPMCs can be specifically activated by TGF-beta1 and influence the process of human peritoneal fibrosis. With the stimulation of TGF-beta1, the protein and mRNA expressions of SMAD 7 (an inhibitor of SMAD pathway) significantly increase as a result of feedback.
Insights
Transforming growth factor-beta1 (TGF-β1) activates the Smad pathway in human peritoneal mesothelial cells (HPMCs), driving peritoneal fibrosis. SMAD 7, an inhibitor, increases via feedback, suggesting a regulatory mechanism in fibrosis development.
Area of Science:
- Cell Biology
- Molecular Biology
- Pathology
Context:
- Human peritoneal fibrosis is a significant complication.
- The role of TGF-β1 signaling in fibrosis is well-established.
- Understanding cellular mechanisms in HPMCs is crucial for therapeutic development.
Purpose:
- To investigate the involvement of the Smad signal transduction pathway in TGF-β1-induced human peritoneal fibrosis.
- To analyze the expression and localization of key Smad proteins and SMAD 7 in HPMCs.
Summary:
- TGF-β1 stimulation rapidly activates p-Smad2/3 in HPMCs, with nuclear translocation observed.
- TGF-β1 also induces time-dependent increases in SMAD 7 protein and mRNA expression, indicating a feedback loop.
- Expressions of fibronectin and collagen I, key fibrosis markers, were significantly upregulated by TGF-β1 in a time-dependent manner.
Impact:
- This study elucidates the specific molecular mechanisms by which TGF-β1 influences peritoneal fibrosis via the Smad pathway.
- Findings highlight SMAD 7 as a potential negative regulator in this process.
- Provides a foundation for targeted therapies aimed at mitigating peritoneal fibrosis.
More Related Videos
07:49Molecular Analysis of Endothelial-mesenchymal Transition Induced by Transforming Growth Factor-β Signaling
Published on: August 3, 2018
06:02Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition
Published on: June 10, 2016
