Abstract

PURPOSE:  To study the effect of fluoride on autophagy in rat ameloblasts both in vitro and in vivo.

METHODS:  Logarithmic-phase HAT-7 cells were cultured in different concentrations of fluoride for 48h. Transmission electron microscopy (TEM) was used to detect autophagosomes. Western blot and RT-qPCR were carried out to examine the expression of LC3 and Beclin 1. Forty Wistar rats were divided into 4 groups randomly. The expression of LC3 and Beclin 1 in rats was investigated by immunohistochemical staining in vivo. The data were analysed using SPSS13.0 software package.

RESULTS:  The amount of autophagosomes in the experimental group was significantly more than that in the control group (P<0.05). The expression of LC3 and Beclin 1 were up-regulated in dose dependent manner after treatment with fluoride. Regression analysis showed that fluoride dependently induced the expression of LC3 and Beclin 1 (P<0.05).Immunohistochemical analysis revealed that the expression of LC3 and Beclin 1 in rat ameloblasts in the experimental groups was positive compared to control group.

CONCLUSIONS:  Excessive fluoride induced autophagy in ameloblasts both in vitro and in vivo.

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