Expression of NLRP3 and P2X7 transcripts in gingival tissues of chronic periodontitis patients and its correlation with P. gingivalis load and periodontal parameters

Abstract

BackgroundInflammasomes are pivotal regulators of the host innate defense in periodontal tissues. Porphyromonas gingivalis modulates NLRP3 inflammasome complex and P2X7 receptor for survival in tissues through its virulence factors. AimTo estimate the expression of NLRP3 and P2X7 in gingival tissues of chronic periodontitis patients and to assess its correlation with periodontal clinical parameters and P. gingivalis load in subgingival plaque samples. Materials and methodsInterproximal gingival tissue and subgingival plaque samples (collected from same site) from systemically healthy chronic periodontitis patients (n = 22) and healthy controls (n = 22) were collected and stored in −80 °C. NLRP3 and P2X7 gene expression in gingival tissues and load of P. gingivalis in sub gingival plaque were assessed using real time Polymerase Chain Reaction. ResultsThe expression of NLRP3 in chronic periodontitis was marginally higher than healthy controls though the difference was statistically insignificant. P2X7 expression was higher in healthy controls and down regulated in chronic periodontitis patients (p = 0.04). A statistically significant correlation was observed between the probing pocket depth and expression of P2X7 gene in chronic periodontitis (p = 0.04). Correlation between P. gingivalis load and expression of the genes in tissues was either moderate (P2X7 control group) or negligible (both test and control of NLRP3). ConclusionA marginal increase in expression of NLRP3 and statistically significant decrease in P2X7 expression in chronic periodontitis patients was present. A statistically significant correlation was observed between P2X7 and P. gingivalis load in control group and periodontal parameters in test group. The study confirms involvement of genes in periodontal pathogenesis.