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Activation of protein serine/threonine phosphatase PP2Cα efficiently prevents liver fibrosis

Lirui Wang1, Xu Wang, Jing Chen

  • 1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.

Plos One
|December 15, 2010
PubMed
Abstract

Insights

Activating protein phosphatase 2C alpha (PP2Cα) inhibits liver fibrosis by halting hepatic stellate cell proliferation and key fibrotic pathways. The small molecule NPLC0393 shows promise as an antifibrotic treatment.

Area of Science:

  • Hepatology
  • Molecular Biology
  • Cell Biology

Background:

  • Liver fibrosis involves overactive TGFβ signaling and hepatic stellate cell (HSC) proliferation.
  • Protein serine/threonine phosphatase PP2Cα negatively regulates TGFβ signaling and cell cycle.
  • The role of PP2Cα in liver fibrogenesis requires further investigation.

Purpose of the Study:

  • To investigate the role of PP2Cα in liver fibrogenesis.
  • To evaluate PP2Cα activation as a potential therapeutic strategy for liver fibrosis.

Main Methods:

  • In vitro studies using human and rat HSCs (western blotting, real-time PCR, cell cycle analysis).
  • In vivo studies in CCl(4)- and bile duct ligation (BDL)-induced mouse models.
  • Assessment of TGFβ-Smad3 and TGFβ-p38 signaling pathways, HSC proliferation, and fibrotic markers (α-SMA, collagen, hydroxyproline).

Main Results:

  • PP2Cα activation, via overexpression or NPLC0393, inhibited TGFβ-Smad3 and TGFβ-p38 signaling.
  • PP2Cα activation induced cell cycle arrest in HSCs.
  • PP2Cα activation reduced α-SMA expression, collagen deposition, and hepatic hydroxyproline levels in fibrotic mice.

Conclusions:

  • PP2Cα activation represents a potential therapeutic strategy for liver fibrosis.
  • The small molecule NPLC0393 may serve as a lead compound for antifibrotic drug development.
  • This study provides evidence for the role of PP2C family members in fibrotic diseases.

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