Intestinal mucosal barrier is injured by BMP2/4 via activation of NF-κB signals after ischemic reperfusion

Mediators Inflamm. 2014:2014:901530. doi: 10.1155/2014/901530. Epub 2014 Jul 16.

Abstract

Intestinal ischemic reperfusion (I/R) can cause dysfunction of the intestinal mucosal barrier; however, the mechanism of the intestinal mucosal barrier dysfunction caused by I/R remains unclear. In this study, using intestinal epithelial cells under anaerobic cultivation and an in vivo rat intestinal I/R model, we found that hypoxia and I/R increased the expression of BMP2/4 and upregulated BMP type Ia receptor and BMP type II receptor expression. We also found that exogenous BMP2/4 can activate the ERK and AKT signaling pathways in rat small intestine (IEC-6) cells, thereby activating NF-κB signaling, which leads to increased levels of inflammatory factors, such as TNF-α and IL-6. Furthermore, recombinant BMP2/4 decreased the expression of the tight junction protein occludin via the activation of the NF-κB pathway; these effects were abolished by treatment with the BMP-specific antagonist noggin or the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC). All these factors can destroy the intestinal mucosal barrier, thereby leading to weaker barrier function. On the basis of these data, we conclude that BMP2/4 may act as the pathogenic basis for intestinal mucosal barrier dysfunction when the intestines suffer an I/R injury. Our results provide background for the development pharmacologic interventions in the management of I/R injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Bone Morphogenetic Protein 2 / metabolism*
  • Bone Morphogenetic Protein 4 / metabolism*
  • Cell Line
  • Interleukin-6 / metabolism
  • Intestinal Mucosa / drug effects*
  • Intestinal Mucosa / metabolism*
  • Male
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / metabolism*
  • Pyrrolidines / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Reperfusion Injury / metabolism*
  • Signal Transduction / drug effects
  • Thiocarbamates / pharmacology
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Bone Morphogenetic Protein 2
  • Bone Morphogenetic Protein 4
  • Interleukin-6
  • NF-kappa B
  • Pyrrolidines
  • Thiocarbamates
  • Tumor Necrosis Factor-alpha
  • pyrrolidine dithiocarbamic acid