Evaluation of the protease activated receptor 2(PAR-2) expression in chronic periodontitis patients, before and after non-surgical periodontal treatment

Abstract

The association of protease activated receptor 2 (PAR-2) with periodontitis, an oral chronic inflammation that leads to bone loss and consequently to tooth loss, was first suggested by in vitro studies which have demonstrated that osteoblasts, epithelial cells and human gingival fibroblasts express PAR-2. In addition, it was observed that local administration of a PAR-2 selective agonist (SLIGRL) causes gingival granulocyte infiltration and periodontitis in rats. Furthermore, PAR-2 knockout mice (PAR-2-/-) showed less inflammation due to Porphyromonas gingivalis (Pg) infection. In a recent study by our group, we have shown that in chronic periodontitis patients, an increased genetic expression of PAR-2 is associated to the presence of increased levels of pro-inflammatory mediators, total proteolytic activity, proteinase-3, and increased Pg prevalence, from which gingipain is derived. However, these results did not show whether this genetic expression is found increased due to the presence of periodontal disease or due to a constitutive feature that favors the commencement of periodontal disease. Therefore, in this present study, crevicular cells will be evaluated regarding the correlation between genetic and protein expression of PAR-2 (Real Time-PCR, Western blot) and the periodontal clinical parameters in human chronic periodontitis, before and after conventional periodontal treatment.