MiRNA-181a regulates Toll-like receptor agonist-induced inflammatory response in human fibroblasts

Genes Immun. 2014 Jul-Aug;15(5):333-7. doi: 10.1038/gene.2014.24. Epub 2014 May 22.

Abstract

MicroRNAs (miRNAs) regulate the synthesis of cytokines in response to Toll-like receptor (TLR) activation. Our recent microarray study comparing normal and inflamed human dental pulps showed that miRNA-181 (miR-181) family is differentially expressed in the presence of inflammation. Prior studies have reported that the dental pulp, which is composed primarily of TLR4/2+ fibroblasts, expresses elevated levels of cytokines including interleukin-8 (IL-8) when inflamed. In this study, we employed an in-vitro model to determine the role of the miRNA-181 family in the TLR agonist-induced response in human fibroblasts. TLR4/2+ primary human dental pulp fibroblasts were stimulated with lipopolysaccharide from Porphyromonas gingivalis (Pg LPS), a known oral pathogen, and IL-8 and miR-181 expression measured. An inversely proportional relationship between IL-8 and miR-181a was observed. In-silico analysis identified a miR-181a-binding site on the 3' untranslated region (UTR) of IL-8, which was confirmed by dual-luciferase assays. MiR-181a directly binds to the 3'UTR of IL-8, an important inflammatory component of the immune response, and modulates its levels. This is the very first report demonstrating miR-181a regulation of IL-8.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Binding Sites
  • Cells, Cultured
  • Dental Pulp / cytology
  • Fibroblasts / immunology
  • Fibroblasts / metabolism*
  • Humans
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism*
  • Lipopolysaccharides / pharmacology
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Toll-Like Receptors / agonists

Substances

  • 3' Untranslated Regions
  • Interleukin-8
  • Lipopolysaccharides
  • MIrn181 microRNA, human
  • MicroRNAs
  • Toll-Like Receptors