The Effects of Vitamins A, D, E, and C on Apoptosis and Dna Damage in Sodium Fluoride-Treated Renal and Osteoblast Cell Lines

Abstract

This study was planned to investigate the effects of the antioxidant and protective vitamins A, D, E, and C, on the expression and translation of certain apoptotic markers in the NRK-52E and hFOB 1.19 cell lines treated with NaF at half the maximal inhibitory concentration (IC50) for 24 hours. The IC50 for NaF and nontoxic vitamin doses were determined by the MTT viability test. For the biochemical assays, cells were harvested by trypsinization and lysed by the freeze/thaw method. The levels and gene expression of caspases 3, 8, and 9, and the levels of M30 and 8-OHdG were also measured with methods that included the use of ELISA and qRT-PCR. In the MTT studies, compared to the NaF-treated groups, it was found that the cell viability was higher in all the NaF+vitamin D-treated groups in the NRK-52E cell line, in some of the NaF+vitamin D-treated groups in the hFOB 1.19 cell line, and in some of the NaF+vitamin A, E, and C-treated groups for both cell lines. In the NRK-52E cell line, the NaF IC50 value was determined and found not to induce apoptosis sufficiently so that it was considered that mechanisms other than the apoptotic pathways were instrumental in causing cell death. In the hFOB 1.19 cell line, it was observed that the apoptotic M30 protein level was increased in the NaF+vitamin D and NaF+vitamin C groups. In addition, in the hFOB 1.19 cell line, the qRT-PCR results showed that, while the expression of caspase-3 increased with vitamin A and that of caspase-8 increased with NaF, treatment with NaF+vitamin A led to a lower levels of caspases 3 and 8. Future studies to investigate the most valid and active mechanism for NaF-induced cell death and to elucidate the inhibitory-activating effects of vitamins on this mechanism using different doses, durations of exposure, and analytic methods should be considered.