Rosiglitazone reduces the evolution of experimental periodontitis in the rat

The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) receptor appears to play a pivotal role in the regulation of cellular proliferation and inflammation. Recent evidence also suggests that rosiglitazone, a PPAR-gamma agonist, reduces acute and chronic inflammation. We hypothesized that rosiglitazone would attenuate periodontal inflammation. In the present study, we investigated the effects of rosiglitazone in a rat model of ligature-induced periodontitis. At day 8, ligation significantly induced an increase in neutrophil infiltration, as well as of gingivomucosal tissue expression of iNOS, nitrotyrosine formation, and poly (ADP-ribose) polymerase activation. Ligation significantly increased Evans blue extravasation in gingivomucosal tissue and alveolar bone destruction. Intraperitoneal injection of rosiglitazone (10 mg/kg 10% DMSO daily for 8 days) significantly decreased all of the parameters of inflammation, as described above. Analysis of these data demonstrated that rosiglitazone exerted an anti-inflammatory role during experimental periodontitis, and was able to ameliorate the tissue damage associated with ligature-induced periodontitis.