Therapeutic effects of 3,3′-diindolylmethane on the alveolar bone in mice with experimentally induced periodontitis

In this study, we investigated effects of 3,3′-diindolylmethane (DIM) on alveolar bone resorption in mice with experimentally induced periodontitis. Experimental periodontitis was induced by placing 5.0 silk sutures around the maxillary left second molar for 1 week. Fifty-three SPF, 6-8-week-old, female C57 mice were randomly divided into four groups: (1) healthy mice (control group), (2) mice with experimentally induced periodontitis (Ped group), (3) mice with periodontitis treated with corn oil (OIL-Ped group) and (4) mice with periodontitis treated with DIM dissolved in corn oil (DIM-Ped group). Infiltration of inflammatory cells in the gingival tissue was assessed via histomorphometrical analysis, inflammatory factors were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and changes in the alveolar bone were detected by micro-computed tomography (micro-CT) after treatment for 1 and 4 weeks. After 1 week of treatment, compared with the Ped and OIL-Ped groups, the DIM-Ped group showed decreased infiltration of inflammatory cells, preservation of connective tissue in the papilla and less interproximal and interradicular bone resorption. In the DIM-Ped group, the expression of IL-1β and RANKL decreased significantly (P