Fluoride Action Network



  • Chronic fluorosis decreased learning and memory of rats and induced neurotoxicity.
  • Thirteen corresponding DEGs and DAPs (cor-DEGs-DAPs) were identified.
  • Most of cor-DEGs-DAPs were related to neurodegenerative changes and oxidative stress response
  • The neurotoxicity by high fluoride involved in the changes in cholinergic pathway and oxidative stress.


To reveal the underling molecular mechanism in brain damage induced by chronic fluorosis, the neurotoxicity and its correlation were investigated by transcriptomics and proteomics.


Sprague-Dawley rats were treated with fluoride at different concentrations (0, 5, 50 and 100 ppm, prepared by NaF) for 3 months. Spatial learning and memory were evaluated by Morris water maze test; neuronal morphological change in the hippocampus was observed using Nissl staining; and the level of oxidative stress including reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) were detected by biological methods. The high-throughput transcriptome sequencing (RNA-Seq) and tandem mass tag (TMT) proteomic sequencing were performed to detect the expression of differentially expressed genes and proteins, respectively.


The results showed that compared with control group, rats exposed to high-dose fluoride exhibited declined abilities of learning and memory, decreased SOD activity and increased ROS and MDA levels, with lighter colored Nissl bodies. A total of 28 important differentially expressed genes (DEGs) were screened out by transcriptomics. Then, functional enrichment analyses showed that upregulated proteins enriched in cellular transport, while downregulated proteins enriched in synapse-related pathways. Thirteen corresponding DEGs and DAPs (cor-DEGs-DAPs) were identified by differential expressions selected with positively correlated genes/proteins, most of which were related to neurodegenerative changes and oxidative stress response.


These results provide new omics evidence that rats chronically exposed to high-dose fluoride can induce neurotoxicity in the brains through changes in the cholinergic pathway and oxidative stress.

*Original abstract online at https://www.sciencedirect.com/science/article/abs/pii/S0946672X20302534?via%3Dihub