Abstract

To investigate the effects of fluoride on the expression levels of cytokines in the rat hippocampus, 60 adult Wistar albino rats were randomly divided into four groups of 15 rats each, whose drinking water contained: (1) double distilled water (the control group); (2) 25 mg sodium fluoride (NaF)/L, (11.3 mg F/L); (3) 50 mg NaF/L, (22.6 mg F/L); and (4) 100 mg NaF/L, (45.2 mg F/L). After five months treatment, the expression levels of the cytokines TGF-B1, IL-4, IL-1B, IL-6, and TNF-B gene were determined by real-time PCR, and the TGF-B1 protein levels were detected by ELISA. A significant decrease of TGF-B1 was found, in both the gene and protein levels, while no significant change occurred in the levels of IL-4, IL-1B, IL-6, and TNF-a gene. Fluoride may damage the hippocampus by significantly decreasing the expression of TGF-B1 gene and protein, possibly by an unknown post-transcriptional mechanism. The study provides a new perspective for evaluating the neurotoxicity of fluoride.