Role of TLR5 in inflammation and tissue damage after intestinal ischemia-reperfusion injury

Biochem Biophys Res Commun. 2019 Oct 29;519(1):15-22. doi: 10.1016/j.bbrc.2019.08.083. Epub 2019 Aug 28.

Abstract

Background: Intestinal ischemia/reperfusion (I/R) injury is a life-threatening complication that leads to inflammation and remote organ damage. However, the underlying mechanism is not yet fully understood. Toll-like receptor 5 (TLR5) is highly expressed in mucosa and recognizes flagellin, the main component of the bacterial flagella. Here, we investigated the role of TLR5 in inflammation and tissue damage after intestinal I/R injury using TLR5-deficient mice.

Methods and results: Intestinal levels of TLR5 mRNA and flagellin protein were elevated in wild-type mice subjected to intestinal I/R. Although TLR5 deficiency had no effect on intestinal flagellin levels, it significantly attenuated intestinal injury and inflammatory responses after intestinal I/R. TLR5 deficiency also markedly improved survival in mice after intestinal I/R injury. In wild-type mice, intestinal I/R injury induced remote organ damage, particularly in the lung, which was attenuated by TLR5 deficiency. Furthermore, TLR5 deficiency prevented lung inflammatory responses and vascular permeability after intestinal I/R injury.

Conclusion: These findings demonstrate a novel role of TLR5 and provide new insights into the mechanism underlying inflammation and tissue damage after intestinal I/R injury.

Keywords: Cytokines; Inflammation; Interleukin; Intestine; Lung.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Inflammation / metabolism*
  • Inflammation / pathology
  • Intestinal Mucosa / metabolism*
  • Intestinal Mucosa / pathology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Reperfusion Injury / metabolism*
  • Reperfusion Injury / pathology
  • Toll-Like Receptor 5 / metabolism*

Substances

  • Tlr5 protein, mouse
  • Toll-Like Receptor 5