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Adding fuel to fire: microRNAs as a new class of mediators of inflammation

F J Sheedy1, L A J O'Neill

  • 1School of Biochemistry and Immunology, Trinity College Dublin, Ireland. sheedyf@tcd.ie

Annals of the Rheumatic Diseases
|December 17, 2008
PubMed

Insights

MicroRNAs regulate gene expression and are implicated in inflammation. Specific microRNAs, miR-146 and miR-155, are involved in inflammatory responses and rheumatoid arthritis pathogenesis.

Area of Science:

  • Molecular Biology
  • Immunology
  • Genetics

Background:

  • MicroRNAs (miRNAs) are key gene expression regulators.
  • Dysregulated miRNAs are linked to cancer and inflammatory diseases.
  • miRNAs target messenger RNAs (mRNAs) to inhibit protein translation.

Purpose of the Study:

  • To investigate the role of specific microRNAs in inflammatory disease pathogenesis.
  • To examine the function of miR-146 and miR-155 in inflammation and rheumatoid arthritis.

Main Methods:

  • Analysis of miRNA expression in inflammatory contexts.
  • Identification of miRNA targets and regulatory pathways.
  • Detection of miRNAs in relevant cell types like synovial fibroblasts.

Main Results:

  • miR-146 and miR-155 are induced by pro-inflammatory stimuli (e.g., interleukin 1, tumor necrosis factor alpha, Toll-like receptors).
  • These miRNAs are present in rheumatoid synovial tissue.
  • miR-146 inhibits Toll-like receptor signaling; miR-155 regulates Th1 cells and positively regulates tumor necrosis factor alpha mRNA.

Conclusions:

  • MicroRNAs, particularly miR-146 and miR-155, play significant roles in inflammatory processes.
  • These miRNAs are implicated in the pathogenesis of rheumatoid arthritis.
  • MicroRNAs offer substantial potential for understanding and treating inflammatory diseases.

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