Effects of a Mikania laevigata extract on bone resorption and RANKL expression during experimental periodontitis in rats

Objectives: the mikania laevigata extract (mle) (popularly known in brazil as guaco) possesses anti-inflammatory properties. in the present study we tested the effects of mle in a periodontitis experimental model in rats. we also investigated possible mechanisms underlying such effects. material and methods: periodontal disease was induced by a ligature placed around the mandibular first molars of each animal. male wistar rats were divided into 4 groups: non-ligated animals treated with vehicle; non-ligated animals treated with mle (10 mg/kg,daily); ligature-induced animals treated with vehicle and ligature-induced animals treated with mle (10 mg/kg,daily). thirty days after the induction of periodontal disease,the animals were euthanized and mandibles and gingival tissues removed for further analysis. results: morphometric analysis of alveolar bone loss demonstrated that mle-treated animals presented a decreased alveolar bone loss and a lower expression of the activator of nuclear factor-κb ligand (rankl) measured by immunohistochemistry. moreover,gingival tissues from the mle-treated group showed decreased neutrophil migration myeloperoxidase (mpo) assay. conclusions: these results indicate that mle may be useful to control bone resorption during progression of experimental periodontitis in rats.