Sonic Hedgehog contributes to gastric mucosal restitution after injury

Lab Invest. 2013 Jan;93(1):96-111. doi: 10.1038/labinvest.2012.148. Epub 2012 Oct 22.

Abstract

Eradication of Helicobacter pylori correlates with regeneration of the gastric epithelium, ulcer healing and re-expression of the gastric morphogen Sonic Hedgehog (Shh). We sought to identify the role of Shh as a regulator of gastric epithelial regeneration during wound healing. A mouse model expressing a parietal cell-specific, tamoxifen-inducible deletion of Shh (HKCre(ERT2);Shh(flox/flox) or PC-iShhKO) was developed. Stomachs were collected and compared 7-150 days after the final vehicle or tamoxifen injection. Ulcers were induced in both controls and PC-iShhKO mice using acetic acid and ulcer size compared 1 and 7 days post induction. (1) Re-expression of Shh correlates with decreased hyperproliferation: Compared to controls, PC-iShhKO mice developed foveolar hyperplasia. Restoration of normal gastric epithelial architecture and differentiation correlated with the re-expression of Shh in PC-iShhKO mice 150 days after the final tamoxifen injection. At the tamoxifen dose used to induce Cre recombination there was no genotoxicity reported in either HKCre(ERT2) or Shh(flox/flox) control mouse stomachs. (2) Delayed wound healing in PC-iShhKO mouse stomachs: To identify the role of Shh in gastric regeneration, an acetic acid ulcer was induced in control and PC-iShhKO mice. Ulcers began to heal in control mice by 7 days after induction. Ulcer healing was documented by decreased ulcer size, angiogenesis, macrophage infiltration and formation of granulation tissue that correlated with the re-expression of Shh within the ulcerated tissue. PC-iShhKO mice did not show evidence of ulcer healing. Re-expression of Shh contributes to gastric regeneration. Our current study may have clinical implications given that eradication of H. pylori correlates with re-expression of Shh, regeneration of the gastric epithelium and ulcer healing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • Gastric Mucosa / chemistry
  • Gastric Mucosa / cytology
  • Gastric Mucosa / metabolism*
  • Hedgehog Proteins / genetics
  • Hedgehog Proteins / metabolism*
  • Kruppel-Like Transcription Factors / genetics
  • Kruppel-Like Transcription Factors / metabolism
  • Macrophages / metabolism
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism
  • Mice
  • Mice, Knockout
  • Platelet Endothelial Cell Adhesion Molecule-1 / genetics
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism
  • RNA, Messenger / analysis
  • Stomach Ulcer / metabolism*
  • Tamoxifen
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism
  • Wound Healing / physiology*
  • Zinc Finger Protein GLI1

Substances

  • Carrier Proteins
  • Gli1 protein, mouse
  • Hedgehog Proteins
  • Hhip protein, mouse
  • Kruppel-Like Transcription Factors
  • Membrane Glycoproteins
  • Platelet Endothelial Cell Adhesion Molecule-1
  • RNA, Messenger
  • Shh protein, mouse
  • Vascular Endothelial Growth Factor A
  • Zinc Finger Protein GLI1
  • vascular endothelial growth factor A, mouse
  • Tamoxifen