Impact of fluoride exposure from early life to adulthood on learning and memory abilities and the hippocampal NOTCH signaling pathway in offspring mice
10.3760/cma.j.cn231583-20241118-00390
- VernacularTitle:生命早期至成年期氟暴露对子代小鼠学习记忆能力与海马NOTCH信号通路的影响
- Author:
Ling LIU
1
;
Qi WU
1
;
Xueli PAN
1
Author Information
1. 贵州医科大学公共卫生与健康学院 环境污染与疾病监控教育部重点实验室，贵阳 561113
- Publication Type:Journal Article
- Keywords:
Fluoride;
Offspring mice;
Learning and memory;
Hippocampus;
NOTCH signaling pathway
- From:
Chinese Journal of Endemiology
2025;44(11):861-867
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the effects of fluoride exposure from early life to adulthood on learning and memory abilities of offspring mice and the expression of genes related to the NOTCH signaling pathway in hippocampal tissue.Methods:Thirty 8-week-old (body weight 18 - 24 g) clean-grade C57BL/6J mice, half male and half female, were randomly divided into 3 groups by body weight and then paired 1 ∶ 1 (10 mice per group). Successfully pregnant female mice were given tap water containing 0 (control), 20, or 40 mg/L sodium fluoride (NaF) during gestation and lactation until weaning. Offspring mice were exposed to fluoride until 12 weeks of age after weaning at 21 days, with fluoride exposure doses identical to those of the maternal mice. The 24-hour urine of the offspring mice was collected to determine urine fluoride level using fluoride ion selective electrode method, and Morris water maze was used to evaluate their spatial learning and memory ability. The offspring mice were euthanized under anesthesia, and protein and RNA were extracted from hippocampal tissue. Western blot was used to detect the protein expression levels of postsynaptic density protein 95 (PSD95) and synapsin-1 (SYN-1) in hippocampal tissues. Quantitative real-time PCR and Western blot were used to detect the mRNA and protein expression levels of NOTCH signaling pathway related genes (including NOTCH1, DLL3, HES5) in hippocampal tissue.Results:Compared with the control group [(0.86 ± 0.25) mg/L], the offspring mice of the 20 and 40 mg/L NaF groups had higher urinary fluoride levels [(3.77 ± 0.51), (6.04 ± 1.63) mg/L, P < 0.05]. The Morris water maze results showed that compared with the control group, the offspring mice in the 20 and 40 mg/L NaF groups had longer escape latency (day 5), fewer platform crossings, and shorter target platform dwell time ( P < 0.05). Compared with the control group, the protein expression level of synaptic related protein PSD95 in the hippocampal tissues of the offspring mice in the 40 mg/L NaF group was lower, and the protein expression level of SYN-1 in the 20 and 40 mg/L NaF groups was lower ( P < 0.05). The protein expression level of NOTCH1, a gene related to the NOTCH signaling pathway, was lower in the hippocampal tissue of offspring mice in the 40 mg/L NaF group. The mRNA and protein expression levels of DLL3 and HES5 were also lower in the 20 and 40 mg/L NaF groups, and the mRNA expression level of HES5 in the 40 mg/L NaF group was lower than that in the 20 mg/L NaF group ( P < 0.05). Conclusions:Exposure to fluoride from early life to adulthood can lead to a decline in the learning and memory abilities of offspring mice, as well as a decrease in the expression of synaptic related proteins. The mechanism of action may be related to the inhibition of the NOTCH signaling pathway in hippocampal tissue.
