Objective To investigate the expressions of receptor for advanced glycation endproducts (RAGE) and nuclear factor kB (NF-kB) in brain hippocampus of rat with chronic fluorosis, and to reveal the mechanism of brain damage resulted from chronic fluorosis.
Methods Sixty clean grade SD rats were randomly divided to three groups (20 rats in each group,10 female and 10 male) fed with different contents of fluoride, control group with normal tap-water (< 0.5 mg/L fluoride), small dosage of fluoride exposure group (10 mg/L fluoride in tap-water) and large dosage of fluoride exposure group (50 mg/L fluoride) for six months.Then the rats were killed by femoral artery bleeding and hippocampus was removed. Protein and mRNA levels of RAGE and NF-kB in the hippocampus were determined by Western blotting and quantitative real time PCR, respectively.
Results As compared to the control groups [(100.00 ± 2.60)%, (100.00 ± 7.80)%], the expressions of RAGE and NF-kB at protein level in the hippocampus were significantly increased in the small dosage of fluoride exposure groups [(205.00 ± 15.30)%, (156.00 ± 12.20)%] and the large dosage of fluoride exposure groups [(232.00 ± 10.90)%, (162.00 ± 9.80)%, all P < 0.05]; for the mRNA level of RAGE and NF-kB, the expressions were higher in the small dosage of fluoride exposure groups (1.27 ± 0.09, 0.83 ± 0.15) and the large dosage of fluoride exposure groups (2.60 ± 0.19, 1.27 ± 0.19) than those of the control groups (0.66 ± 0.18, 0.32 ± 0.08, all P < 0.05).
Conclusions The increased expressions of RAGE and NF-kB in the hippocampus of rat brain are caused by chronic fluorosis,and these changes may be associated with the mechanism of nerve injury.