Effects of Fluoride Exposure on Cell Proliferation and Osteogenic Differentiation of Periodontal Ligament Stem Cells

doi:10.13701/j.cnki.kqyxyj.2020.09.015

Abstract

Abstract: Objective: To disclose the biological effects of fluoride (F) exposure on cell proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs). Methods: PDLSCs were isolated and cultured from human periodontal ligament tissues. The surface markers of passage 3 cells were analyzed by flow cytometry. After treated with different concentrations of F (0.1-40 mg/L) for indicated period of time, the effects of F exposure on cell proliferation (CCK-8 assay), capability of colony-forming, cell circle phase changes (flow cytometry), as well as the osteogenic potential (Alizarin red staining and Western blot assay of expression of RUNX2 and ALP) were examined. Results: F exposure affected the cell proliferation and osteogenic differentiation of PDLSCs in a dose- and time-dependent manner. 0.1-10 mg/L F did not significantly affect cell proliferation (P>0.05), while 0.1 and 1 mg/L F significantly enhanced the osteogenic potential, which manifested as increased calcified nodules and upregualtion of RUNX2 and ALP expression (P<0.05). High dose of F (20 and 40 mg/L) significantly inhibited the cell proliferation (P<0.05), exhibiting remarkable cytotoxicity. Conclusion: F exposure affects the proliferation and osteogenic differentiation of PDLSCs. High concentration of F inhibits the proliferation of PDLSCs, while low F concentration (0.1 and 1 mg/L) has no significant effect on the proliferation of PDLSCs, and can promote cell osteogenic differentiation.

Key words: periodontal ligament stem cells, fluoride exposure, cell proliferation, cell differentiation

QIU Yinfeng, TANG Ying, SHEN Yifen, LIU Chao, SHEN Hao, GU Yongchun, YU Jinhua. Effects of Fluoride Exposure on Cell Proliferation and Osteogenic Differentiation of Periodontal Ligament Stem Cells[J]. Journal of Oral Science Research, 2020, 36(9): 866-870.

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