Osteogenic effect of Drynariae rhizoma extracts and Naringin on MC3T3-E1 cells and an induced rat alveolar bone resorption model

Objective: To investigate if Drynariae rhizoma (DR) and its main ingredient Naringin could reduce alveolar bone loss by stimulating the proliferation and differentiation of osteoblasts. Materials and methods: The effect of DR water (DRWE), ethanolic extract (DREE), and Naringin on MC3T3-E1 cells was evaluated respectively by MTT method and by measuring the activity of alkaline phosphatase (ALP activity) as well as the level of osteocalcin in medium. Bone mineral density (BMD) detection, osteoclast counting by tartrate resistant acid phosphatase staining, and histopathological analysis were performed in an induced rat model of alveolar bone resorption after gastric perfusion with DR extracts or Naringin. Results: DRWE and Naringin effectively increased the proliferation of MC3T3-E1 cells, whilst DREE and Naringin enhanced the differentiation of osteoblastic cells. The in vivo study indicated an elevated BMD value in the tooth-periodontal tissues from DRWE, DREE and Naringin treated groups after 10, 20 and 30 days of perfusion (P < 0.05). In DRWE treated group, the number of osteoclasts at days 10, 20 and 30 decreased remarkably as compared to the corresponding negative controls (P < 0.05), and no osteoclast could be found at day 30. New non-calcified bone-like matrix attached by osteoblasts at the root furcation was also shown. Conclusions: DR could be a supplementary medicine for periodontal therapy as it could reduce bone resorption in rat model of alveolar bone resorption and exert osteogenic effect on osteoblasts. (C) 2011 Elsevier Ltd. All rights reserved.