Effect of fluoride on the viability and apoptosis of ameloblasts in vitro

Abstract

Abstract: PURPOSE: To evaluate the effect of fluoride on viability of rat ameloblasts in vitro. METHODS: The ameloblasts of rat was exposed to different concentrations of NaF (0, 0.4, 0.8, 1.6, 3.2, 6.4 mmol/L) for 24, 48 and 72 hours. CCK-8 assays were performed to measure the cells proliferation; The morphology of apoptosis was observed by Hoechst 33258 staining and the rate of apoptosis was determined by flow cytometry. The data was analyzed using SPSS 13.0 software package. RESULTS: ①The proliferation of ameloblasts was increased when concentrations of NaF between 0.4 mmol/L and 0.8 mmol/L, whereas inhibited at 1.6 mmol/L NaF and above. The effects were in time-dependent manner.②Cells in the 1.6 mmol/L NaF groups showed unclear karyorrhexis and apoptotic cell morphology. The effects were in concentration-dependent manner. CONCLUSIONS: ① Fluoride has two-phase effects to ameloblasts: At low doses, it promoted cell proliferation while at high doses it had negative effects. ②1.6 mmol/L NaF could induce apoptosis of ameloblasts.

Key words: Fluoride, Ameloblast, CCK8, Flow cytometry, Hoechst 33258 fluorescence staining

MA Lin, ZHANG Ying, ZHONG Ming, ZHU Li, ZHANG Kai-qiang, GU He-feng, LIU Lu, ZHANG Si-yu, CHENG Rui-bo. Effect of fluoride on the viability and apoptosis of ameloblasts in vitro[J]. Shanghai Journal of Stomatology, 2014, 23(5): 519-523.

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