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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
12:16

Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells

Published on: December 17, 2015

Porphyromonas gingivalis is associated with protease-activated receptor-2 upregulation in chronic periodontitis

José Américo G Fagundes1, Letícia D Monoo, Vanessa Tubero Euzébio Alves

  • 1Department of Periodontology, University of Taubaté, São Paulo, Brazil.

Journal of Periodontology
|April 26, 2011
PubMed
Abstract

Insights

Porphyromonas gingivalis (Pg) presence in chronic periodontitis sites correlates with increased protease-activated receptor-2 (PAR2) gene expression and elevated inflammatory markers. This suggests Pg drives PAR2-mediated inflammation and periodontal destruction.

Area of Science:

  • Periodontology
  • Microbiology
  • Immunology

Background:

  • Chronic periodontitis patients exhibit elevated protease-activated receptor-2 (PAR2) and inflammatory mediators (IL-1α, IL-6, IL-8, TNF-α).
  • Increased total proteolytic activity and Porphyromonas gingivalis (Pg) prevalence were noted in periodontitis patients compared to healthy controls.

Purpose of the Study:

  • To investigate the relationship between Pg presence at the site level and PAR2 expression in chronic periodontitis.
  • To assess the association of Pg with clinical parameters and inflammatory mediators in periodontal pockets.

Main Methods:

  • Samples from chronic periodontitis patients analyzed for Pg presence using PCR.
  • PAR2 mRNA expression quantified via RT-PCR.
  • Gingival crevicular fluid analyzed for proteolytic activity and inflammatory mediators (IL-1α, IL-6, IL-8, TNF-α).

Main Results:

  • Pg-positive sites showed significantly higher probing depth, clinical attachment level, and bleeding on probing.
  • Proinflammatory mediators (except IL-8) and proteolytic activity were positively associated with Pg presence.
  • Pg presence correlated with increased PAR2 mRNA expression.

Conclusions:

  • Periodontal pockets with Pg exhibit upregulated PAR2 gene expression.
  • Pg presence is linked to a heightened proinflammatory profile and advanced clinical destruction.
  • Pg plays a key role in PAR2-mediated periodontal inflammation in humans.

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