The natural compound celastrol inhibits necroptosis and alleviates ulcerative colitis in mice

Int Immunopharmacol. 2015 Dec;29(2):552-559. doi: 10.1016/j.intimp.2015.09.029. Epub 2015 Oct 9.

Abstract

Ulcerative colitis (UC) is a chronic intestinal inflammatory disease. Necroptosis plays an important role in the pathogenesis of UC. Celastrol, a triterpene from the root bark of the Chinese medicinal plant Tripterygium wilfordii, has been reported to have anti-oxidant and anti-inflammatory activities in colitis. It is not known, however, how celastrol exerts its beneficial effects. The aim of this study is to investigate the effects and possible mechanism of celastrol in UC. Colitis was induced in mice by administration of 5% dextran sulfate sodium (DSS) in drinking water for 4days. Celastrol was administered intraperitoneally (1mg/kg) for 7days after colitis was induced. Our results showed that celastrol treatment ameliorated the severity of colitis, decreased the level of interleukin (IL)-1β, IL-6 and myeloperoxidase (MPO) and upregulated the level of E-cadherin in colitis mice. Moreover, the TUNEL staining and cleaved caspase-3 immunohistochemistry staining proved decreased necrotic cell death after celastrol treatment. On the mechanism, decreased level of necroptosis factors RIP3 and MLKL, and increased level of active caspase-8 were detected after celastrol treatment. Taken together, our results demonstrated that celastrol exerted beneficial effects in colitis treatment via suppressing the RIP3/MLKL necroptosis pathway.

Keywords: Celastrol; MLKL; Necroptosis; RIP3; Ulcerative colitis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Ulcer Agents / administration & dosage
  • Anti-Ulcer Agents / therapeutic use*
  • Caspase 8 / metabolism
  • Cell Death
  • Colitis, Ulcerative / chemically induced
  • Colitis, Ulcerative / drug therapy*
  • Colitis, Ulcerative / pathology
  • Dextran Sulfate
  • Female
  • Injections, Intraperitoneal
  • Interleukin-6 / biosynthesis
  • Interleukin-6 / genetics
  • Mice
  • Mice, Inbred C57BL
  • Necrosis / drug therapy*
  • Necrosis / pathology
  • Pentacyclic Triterpenes
  • Protein Kinases / biosynthesis
  • Protein Kinases / genetics
  • Receptor-Interacting Protein Serine-Threonine Kinases / biosynthesis
  • Receptor-Interacting Protein Serine-Threonine Kinases / genetics
  • Tripterygium / chemistry
  • Triterpenes / administration & dosage
  • Triterpenes / therapeutic use*
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors

Substances

  • Anti-Ulcer Agents
  • Interleukin-6
  • Pentacyclic Triterpenes
  • Triterpenes
  • Tumor Necrosis Factor-alpha
  • interleukin-6, mouse
  • Dextran Sulfate
  • MLKL protein, mouse
  • Protein Kinases
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk3 protein, mouse
  • Caspase 8
  • celastrol