Hypoxia and gastrointestinal disease

J Mol Med (Berl). 2007 Dec;85(12):1295-300. doi: 10.1007/s00109-007-0277-z. Epub 2007 Nov 20.

Abstract

The gastrointestinal mucosa is a richly perfused vascular bed directly juxtaposed with the anaerobic and nonsterile lumen of the gut. As such, intestinal epithelial cells, which line the mucosa, experience a uniquely steep physiologic oxygen gradient in comparison with other cells of the body. Inflammation associated with a loss of epithelial barrier function and unregulated exposure of the mucosal immune system to luminal antigens leads to inflammatory bowel disease (IBD), a relatively common disorder with severe morbidity and a limited therapeutic repertoire. During IBD, increased tissue metabolism and vasculitis renders the chronically inflamed mucosa and particularly the epithelium hypoxic, giving rise to the activation of the hypoxia-responsive transcription factor hypoxia-inducible factor (HIF). Recent studies utilizing conditional intestinal epithelial hif1a-null mice have revealed a protective role for epithelial HIF-1alpha in murine models of IBD. Such protection occurs, at least in part, through HIF-dependent induction of barrier-protective genes in the epithelium. More recently, studies employing pharmacologic activation of HIF via inhibition of HIF prolyl hydroxylases revealed a profoundly protective effect of these agents in murine models of colitis. In this paper, we review this pathway in detail and examine the therapeutic potential for targeting HIF hydroxylases in intestinal mucosal inflammatory disease.

Publication types

  • Review

MeSH terms

  • Animals
  • Cell Hypoxia
  • Enzyme Inhibitors / pharmacology
  • Gastrointestinal Agents / pharmacology
  • Humans
  • Hypoxia / metabolism*
  • Hypoxia-Inducible Factor 1 / metabolism
  • Inflammatory Bowel Diseases / metabolism*
  • Inflammatory Bowel Diseases / prevention & control
  • Intestinal Mucosa / drug effects
  • Intestinal Mucosa / enzymology
  • Intestinal Mucosa / metabolism*
  • Mucositis / metabolism*
  • Mucositis / prevention & control
  • NF-kappa B / metabolism
  • Oxygen / metabolism*
  • Procollagen-Proline Dioxygenase / antagonists & inhibitors
  • Procollagen-Proline Dioxygenase / metabolism
  • Signal Transduction

Substances

  • Enzyme Inhibitors
  • Gastrointestinal Agents
  • Hypoxia-Inducible Factor 1
  • NF-kappa B
  • Procollagen-Proline Dioxygenase
  • Oxygen