Hepatic Progenitor Cells Contribute to the Progression of 2-Acetylaminofluorene/Carbon Tetrachloride-Induced Cirrhosis via the Non-Canonical Wnt Pathway

PLoS One. 2015 Jun 18;10(6):e0130310. doi: 10.1371/journal.pone.0130310. eCollection 2015.

Abstract

Hepatic progenitor cells (HPCs) appear to play an important role in chronic liver injury. In this study, cirrhosis was induced in F-344 rats (n = 32) via subcutaneous injection of 50% carbon tetrachloride (CCl4) twice a week for 8 weeks. Then, 30% CCl4 was administered in conjunction with intragastric 2-acetylaminofluorine (2-AAF) for 4 weeks to induce activation of HPCs. WB-F344 cells were used to provide direct evidence for differentiation of HPCs to myofibroblasts. The results showed that after administration of 2-AAF, the hydroxyproline content and the expressions of α-SMA, Col I, Col IV, TGF-β1, CD68, TNF-α, CK19 and OV6 were significantly increased. OV6 and α-SMA were largely co-expressed in fibrous septum and the expressions of Wnt5b, frizzled2, frizzled3 and frizzled6 were markedly increased, while β-catenin expression was not statistically different among the different groups. Consistent with the above results, WB-F344 cells, treated with TGF-β1 in vitro, differentiated into myofibroblasts and α-SMA, Col I, Col IV, Wnt5b and frizzled2 expressions were significantly increased, while β-catenin expression was decreased. After blocking the non-canonical Wnt pathway via WIF-1, the Wnt5b level was down regulated, and α-SMA and F-actin expressions were significantly decreased in the WIF-1-treated cells. In conclusion, these results indicate that HPCs appear to differentiate into myofibroblasts and exhibit a profibrotic effect in progressive cirrhosis via activation of the non-canonical Wnt pathway. Blocking the non-canonical Wnt pathway can inhibit the differentiation of HPCs into myofibroblasts, suggesting that blocking this pathway and changing the fate of differentiated HPCs may be a potential treatment for cirrhosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Acetylaminofluorene
  • Animals
  • Carbon Tetrachloride
  • Cell Differentiation
  • Female
  • Inflammation / chemically induced
  • Inflammation / immunology
  • Inflammation / pathology
  • Liver / cytology*
  • Liver / drug effects
  • Liver / immunology
  • Liver / pathology*
  • Liver Cirrhosis / chemically induced
  • Liver Cirrhosis / immunology
  • Liver Cirrhosis / pathology*
  • Myofibroblasts / drug effects
  • Myofibroblasts / immunology
  • Myofibroblasts / pathology
  • Rats
  • Rats, Inbred F344
  • Stem Cells / drug effects
  • Stem Cells / immunology
  • Stem Cells / pathology*
  • Wnt Signaling Pathway*

Substances

  • 2-Acetylaminofluorene
  • Carbon Tetrachloride

Grants and funding

This study was supported by the National Natural Science Foundation of China (2011, NO. 81173223) and (2012, NO. 81273728). Dr. Yongping Mu received the funding.