Treatment of Intestinal Fibrosis in Experimental Inflammatory Bowel Disease by the Pleiotropic Actions of a Local Rho Kinase Inhibitor

Gastroenterology. 2017 Oct;153(4):1054-1067. doi: 10.1053/j.gastro.2017.06.013. Epub 2017 Jun 19.


Background: Intestinal fibrosis resulting in (sub)obstruction is a common complication of Crohn's disease (CD). Rho kinases (ROCKs) play multiple roles in TGFβ-induced myofibroblast activation that could be therapeutic targets. Because systemic ROCK inhibition causes cardiovascular side effects, we evaluated the effects of a locally acting ROCK inhibitor (AMA0825) on intestinal fibrosis.

Methods: Fibrosis was assessed in mouse models using dextran sulfate sodium (DSS) and adoptive T-cell transfer. The in vitro and ex vivo effects of AMA0825 were studied in different cell types and in CD biopsy cultures.

Results: ROCK is expressed in fibroblastic, epithelial, endothelial, and muscle cells of the human intestinal tract and is activated in inflamed and fibrotic tissue. Prophylactic treatment with AMA0825 inhibited myofibroblast accumulation, expression of pro-fibrotic factors, and accumulation of fibrotic tissue without affecting clinical disease activity and histologic inflammation in 2 models of fibrosis. ROCK inhibition reversed established fibrosis in a chronic DSS model and impeded ex vivo pro-fibrotic protein secretion from stenotic CD biopsies. AMA0825 reduced TGFβ1-induced activation of myocardin-related transcription factor (MRTF) and p38 mitogen-activated protein kinase (MAPK), down-regulating matrix metalloproteinases, collagen, and IL6 secretion from fibroblasts. In these cells, ROCK inhibition potentiated autophagy, which was required for the observed reduction in collagen and IL6 production. AMA0825 did not affect pro-inflammatory cytokine secretion from other ROCK-positive cell types, corroborating the selective in vivo effect on fibrosis.

Conclusions: Local ROCK inhibition prevents and reverses intestinal fibrosis by diminishing MRTF and p38 MAPK activation and increasing autophagy in fibroblasts. Overall, our results show that local ROCK inhibition is promising for counteracting fibrosis as an add-on therapy for CD.

Keywords: Colitis; Epithelial-to-Mesenchymal Transition; Mesenchymal Cells; Stenosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adoptive Transfer
  • Animals
  • Autophagy / drug effects
  • Case-Control Studies
  • Collagen / metabolism
  • Dextran Sulfate
  • Disease Models, Animal
  • Enzyme Activation
  • Fibrosis
  • Humans
  • Ileum / drug effects*
  • Ileum / enzymology
  • Ileum / immunology
  • Ileum / pathology
  • Inflammatory Bowel Diseases / chemically induced
  • Inflammatory Bowel Diseases / enzymology
  • Inflammatory Bowel Diseases / pathology
  • Inflammatory Bowel Diseases / prevention & control*
  • Interleukin-6 / metabolism
  • Intestinal Obstruction / chemically induced
  • Intestinal Obstruction / enzymology
  • Intestinal Obstruction / pathology
  • Intestinal Obstruction / prevention & control*
  • Male
  • Matrix Metalloproteinases / metabolism
  • Mice, Inbred C57BL
  • Myofibroblasts / drug effects*
  • Myofibroblasts / enzymology
  • Myofibroblasts / immunology
  • Myofibroblasts / pathology
  • Protein Kinase Inhibitors / pharmacology*
  • Signal Transduction / drug effects
  • T-Lymphocytes / immunology
  • T-Lymphocytes / transplantation
  • Time Factors
  • Tissue Culture Techniques
  • p38 Mitogen-Activated Protein Kinases / metabolism
  • rho-Associated Kinases / antagonists & inhibitors*
  • rho-Associated Kinases / metabolism


  • Interleukin-6
  • Protein Kinase Inhibitors
  • interleukin-6, mouse
  • Collagen
  • Dextran Sulfate
  • rho-Associated Kinases
  • p38 Mitogen-Activated Protein Kinases
  • Matrix Metalloproteinases