Abstract
To investigate the effects of sodium fluoride (NaF) on apoptosis, c-Fos mRNA and protein expression levels, and methylation status as well as Dnmt1, Dnmt3a, and Dnmt3b mRNA expression levels in human embryo hepatocyte (L-02) which were exposed to different concentrations of NaF (0, 20, 40, and 80 mg/l) for 24 h in vitro. Results showed that the percentage of apoptosis and c-Fos mRNA and protein expression levels in 40 and 80 mg/l NaF-treated groups were higher than those in the control group (P < 0.05). Further, Dnmt1 mRNA expression level was significantly decreased in the 80 mg/l NaF-treated groups compared to the control group (P < 0.05); Dnmt3a and Dnmt3b mRNA expression levels were significantly decreased in 40 and 80 mg/l NaF-treated groups compared to the control group (P < 0.05). c-Fos methylation levels, according to the bisulfite sequencing results, were decreased in 20, 40, and 80 mg/l NaF-treated groups against the control group. These results suggest that NaF could induce apoptosis and upregulate mRNA and protein expression level of c-Fos as well as decrease mRNA expression levels of Dnmt1, Dnmt3a, and Dnmt3b in L-02 cells. The decrease in c-Fos methylation levels might be involved in the early phase of apoptosis induced by NaF in L-02 cells.
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Acknowledgments
The work was supported by grants from the National Nature Science Foundation of China (Nos. 81072266 and 30972555) and the Foundation in the Ministry of Science and Technology of China (2010DFB30530).
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The authors declare that they have read the manuscript and agree to its submission to the journal, and that the manuscript is original and has not been published elsewhere, all authors have not any potential conflict of interest.
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Niu, Q., Liu, H., Guan, Z. et al. The Effect of c-Fos Demethylation on Sodium Fluoride-induced Apoptosis in L-02 Cells. Biol Trace Elem Res 149, 102–109 (2012). https://doi.org/10.1007/s12011-012-9392-y
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DOI: https://doi.org/10.1007/s12011-012-9392-y