Fluoride Action Network

Abstract

To investigate the effects of fluoride exposure on the microglialmorphology and the expression of inflammatory cytokines in the cerebral cortex of mice, thirty-six ICR male mice were randomly divided into groups and given different doses of sodium fluoride (0, 25, and 50 mg/L NaF). After 50 days, the microglialmorphology and the expression of interleukin-6 (IL-6), interleukin-1B (IL-1B),transforming growth factor-B (TGF-B), and tumor necrosis factor-a (TNF-a) were detected using immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). In our results, the degeneration of pyramidal cells and glial cells was one of the most obvious pathological changes in the fluoride-exposed brains. Compared to the control group, the number of ramified, intermediate, and amoeboid microglia was significantly elevated in the NaF treatment groups. Additionally, the ELISA results showed that 50 mg/L NaF dramatically increased the expression of IL-6, IL-1B, TGF-B,and TNF-a when compared to the control group. These findings suggest that NaF can promote morphological changes of activated microglia and the release of inflammatory factors in the cortex, which may be one of the mechanisms of fluoride-induced nerve damage.