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

ABSTRACT

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 < 0.05). After 4 weeks of treatment, periodontal inflammation level and alveolar bone absorption were similar among groups. However, in the DIM-Ped group, the expression of IL-1β, IL-6 and RANK significantly decreased (P < 0.05). As a whole, DIM treatment for 1 week can benefit alveolar bone recovery by inhibiting the inflammation of the periodontal tissue and expression of bone resorption-related cytokines.

KEYWORDS:

• 3,3′-diindolylmethane
• periodontitis
• bone resorption
• cytokines

Acknowledgements

We are grateful for the technical support from Guangzhou Medical University-Affiliated Stomatology Hospital.

Disclosure statement

The authors report no conflicts of interest related to this study.

Additional information

Funding

This project was supported by the Guangzhou Health and Family Planning Commission under a grant for the Guangzhou traditional Chinese medicine technology project [grant number 20142A011007] and the Guangdong traditional Chinese medicine science and technology plan project [grant number 20141175].