Biological Trace Element Research

, Volume 174, Issue 2, pp 402–409 | Cite as

High-Dose Fluoride Induces Apoptosis and Inhibits Ameloblastin Secretion in Primary Rat Ameloblast

  • Lin WangEmail author
  • Yong Zhu
  • Danyang Wang


The objectives of this study are to establish the in vitro culture system for rat primary ameloblast and to investigate the effects of fluoride on cell viability, apoptosis, and ameloblastin (AMBN) secretion of primary rat ameloblast in vitro. Ameloblast was isolated from the tooth germ of the maxillomandibular molar and cultured in vitro. Cells were treated with NaF at 0.4, 0.8, 1.6, 3.2, and 6.4 mM for 24, 48, and 72 h, respectively. Cell viability was measured by MTT assay and apoptosis was tested by flow cytometry. The activation of Fas ligand (FasL)/Fas pathway was detected using immunoblotting for FasL, Fas, cleaved caspase-8, cleaved caspase-3, and cleaved PARP. Secretion of AMBN in culture medium was measured using ELISA. Primary rat ameloblast was successfully isolated and cultured. The effects of low-dose fluoride on cell viability were bi-phasic, while high-dose fluoride resulted in decreased cell viability uniformly. Fluoride induced ameloblast apoptosis via activation of FasL/Fas signaling pathway and diminished secretion of AMBN by ameloblast. Fluoride could decrease ameloblast viability, induce ameloblast apoptosis via activating FasL/Fas signaling pathway, and reduce AMBN secretion.


Fluoride Ameloblast Primary culture Ameloblastin FasL/Fas 



This study was funded by the special research project of Education Department of Shaanxi Provincial Government (research project number: 2013JK0784).

Compliance with Ethical Standards

This study was approved by the Ethical Committee of Xi’an Medical College. All animal procedures described herein were approved by the Experimental Animal Center of Xi’an Medical College.

Conflict of Interest

The authors declare that they have no competing interests.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of StomatologyXi’an Medical UniversityXi’anChina

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