Methods: Poly(D,L-lactide-co-glycolide) nanocapsules were used to encapsulate 15d-PGJ2, and function as a drug carrier system. Balb/c mice were infected on day 0, 2 and 4 with Aggregatibacter actinomycetecomitans in methylcellulose (2%), and the groups of animals (n=6) were daily treated (15 days) with 1, 3 or 10 µg/kg of 15d-PGJ2-NC (subcutaneously). Control groups were infected but did not receive the drug and another group was not infected. After 15 days, the animals were sacrificed and the submandibular lymph nodes were removed for FACS analysis and the jaws were analyzed for bone resorption. The gingival tissue was used for western blotting and ELISA. Statistical analyses were performed by Bonferroni test.
Results: The infected animals treated with the 15d-PGJ2-NC presented lower bone resorption (dose dependent, p<0.05) in comparison to the animals infected without treatment. Besides, infected-animals treated with 10 µg/kg of 15d-PGJ2-NC had a statistical reduction of CD4+CD25+FOXP3+ cells and CD4/CD8 ratio in the submandibular lymph node (only at 10 µg/kg). Also, CD55 was up-regulated and ICAM-1 was down-regulated in the gingival tissue in the 10 µg/kg-treated group (p<0.05). Elevated amounts of 15d-PGJ2 were found in the gingivae.
Conclusions: The 15d-PGJ2-NC has immunomodulatory effects decreasing the bone resorption and the inflammatory response in periodontitis.