PeerJ. 2020 ;8:e10125. Epub 2020 Oct 7. PMID: 33083147
BS15 improves intestinal environment against fluoride-induced memory impairment in mice-a study based on the gut-brain axis hypothesis.
Background: Excessive fluoride can lead to chronic neurodegeneration characterized by neuron and myelin loss and memory dysfunction. The gut-brain axis hypothesis suggests that gut microbiota plays a crucial role in regulating brain function. Thus, using probiotics to adjust the gut microenvironment may be a potential therapy for mental diseases.Methods: Mice in the prob group were administrated withBS15 for 28 days prior to and throughout a 70-day exposure to sodium fluoride. The drinking water of all groups (F and prob groups) except the control group were replaced by high-fluoride water (100 mg NaF/L) on day 28. Animals in each group were divided into two subsets: one underwent behavioral test, and the other was sacrificed for sampling. The mRNA expression level and protein content related to inflammatory reaction in the ileum and hippocampus were respectively detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of proteins related to myelin structure, apoptosis, and memory in the hippocampus and tight junction proteins in the ileum were determined by RT-qPCR and/or immunohistochemistry. Gut permeability markers (D-lactate and diamine oxidase (DAO)) in the serum were also examined by ELISA.Results: The results showed that fluoride exposure induced a lower spontaneous exploration (