Fluoride induced down-regulation of IKBKG Gene expression inhibits hepatocytes senescence

Background: Accumulating evidences have confirmed that liver is one of the more severely damaged organs during chronic fluorosis. However, the detail mechanism is unclear to data. At present, the objective of this study was to investigate the relationship between down-regulation of IKBKG gene expression and hepatocyte senescence induced by sodium fluoride (NaF).

Methods: Chronic fluorosis rats and NaF-exposure human liver L02 cells were reproduced the model of hepatocyte senescence in vivo and in vitro. The mRNA and protein levels of p16, p21 and IKBKG, the IL-8 level were determined. The role of IKBKG in fluoride-induced senescence of hepatocytes was explored by knock down in hepatocytes in vivo and in vitro.

Results: The number of senescence-positive cells in rat liver tissues was increased as well as the level of IL-8 and the expression levels of p16, p21 and IKBKG in fluoride exposure to rat depending on the fluoride concentration. The similar results were obtained in NaF treated liver L02 cells, and the number of cells that stagnated in the G2 phase increased significantly. Further, our results confirmed that decreasing the expression of IKBKG in hepatocytes could reduce fluoride-induced hepatocyte senescence and the changes of senescence-related indicators both in vivo and in vitro.

Conclusion: These results indicated that the elevated expression of IKBKG was positive relation with the fluoride-induced senescence in hepatocytes, suggesting the hepatocyte senescence might have a special relationship with fluoride-caused liver damage. Because of the present results limitation, the mechanism of fluoride induced senescence in hepatocytes should be concentrated in the future in detail, especially the novel targets for fluoride induced liver injury.