Epithelial–mesenchymal transition of rat peritoneal mesothelial cells via Rhoa/Rock pathway

  • Hao Zhang
  • Xiaoxian Liu
  • Yan Liu
  • Bin Yi
  • Xueqing Yu


The objective of this study was to investigate the role of the RhoA/Rock signaling pathway in the epithelial–mesenchymal transition (EMT) of rat peritoneal mesothelial cells (RPMCs). Primary SD rat peritoneal mesothelial cells were cultured in vitro. RPMCs were randomly assigned to four groups: group A (control), group B (TGF-β1, 10 μg/L), group C (10 μg/L TGF-β1 + 10 μmol/L Y-27632, an inhibitor of Rock that was pre-applied for 2 h before TGF-β1 stimulation), and group D (Y-27632 alone, 10 μmol/L). Our results were as follows: (1) TGF-β1 stimulation elicited a robust increase in RhoA activity in a time-dependent manner; the increase was 2.57 ± 0.52 times larger than the activity observed for the control group (P < 0.05) after 10 min of stimulation. RhoA activity peaked at 1 h and was 4.35 ± 0.41 times the value observed for the control group (P < 0.05). (2) TGF-β1 up-regulated mRNA and/or protein expression of α-SMA, vimentin, and collagen and down-regulated mRNA and protein expression of E-cadherin in RPMCs. (3) The Rock inhibitor Y-27632 effectively reduced TGF-β1-induced expression of α-SMA, collagen, and vimentin; the mRNA levels of α-SMA and collagen decreased by 53.8% and 55.7%, respectively, and the protein levels of α-SMA, vimentin, and collagen decreased by 42.6%, 60.1%, and 58.1%, respectively, as compared to TGF-β1-stimulated groups (P < 0.05). However, the Rock inhibitor Y-27632 had no effect on the level of E-cadherin. In conclusion, the RhoA/Rock signaling pathway may mediate EMT induced by TGF-β1 in rat peritoneal mesothelial cells. The RhoA/Rock pathway may be a potential therapeutic target for the treatment of peritoneal fibrosis.


Retroperitoneal fibrosis Peritoneal dialysis RhoA/Rock signaling pathway Peritoneal mesothelial cells Epithelial–mesenchymal transition 


Competing interests

The authors declare that they have no competing interests.


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Copyright information

© The Society for In Vitro Biology 2010

Authors and Affiliations

  • Hao Zhang
    • 1
  • Xiaoxian Liu
    • 1
  • Yan Liu
    • 1
  • Bin Yi
    • 1
  • Xueqing Yu
    • 2
  1. 1.Division of Nephrology, The Third Xiangya HospitalSouth Central UniversityHunanChina
  2. 2.Sun Yat-sen UniversityGuangzhouChina

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