The Effect Of Puerarin On Alleviation Of Neurotoxicity-induced By Bisphenol S Via Intestinal-brain Axis And Its Mechanism

Objective(s)In this study,we observed the effects of bisphenol S on the nervous system and colon of adult male C57BL/6 mice,explored the efficacy of puerarin in alleviating the neurotoxicity of bisphenol S,and further clarified the role of the gut-brain axis in the neurotoxicity of bisphenol S.Method(s)1.Thirty-six 8 male C57BL/6 mice were randomly divided into the control group,BPS group,and PUE+BPS group,12 mice in each group.The mice were treated with 150mg/kg PUE in the PUE+BPS group at 10 am every day,the same amount of distilled water in the control group and BPS group,and 50mg/kg BPS in the BPS group and PUE+BPS group at16 pm every day,and the same amount of sesame oil in the control group for seven weeks.2.Morris water maze test(MWM)and open field test(OPT)were used to evaluate the neurological function of mice.3.After the poisoning,pentobarbital was put to death under anesthesia.Hematoxylin-eosin(H&E)staining was used to observe the pathological changes of the brain.The expression of BDNF protein in serum of mice was detected by ELISA,and the m RNA and protein levels of SYN1,SYP,PSD-95,BDNF,Trk B and CREB were detected by q RT-PCR and Western Blot respectively.4.The pathological changes of colon were observed with hematoxylin-eosin(H&E)staining and periodic acid-Schiff(PAS)staining.The m RNA and protein levels of the colonic mucosal barrier markers ZO-1,OCLN,and CLD1 were detected by q RT-PCR and Western Blot.The m RNA and protein levels of IL-1β,IL-6,IL-8,IL-17 A,TNF-α and IFN-γ,which are related to colonic inflammation,were detected by q RT-PCR and Western Blot.5.Anus stimulation method was used to collect mouse feces.Analysis of intestinal flora changes based on 16 S r DNA sequencing technology.The changes of short-chain fatty acids(SCFA)were analyzed by UHPLC-MS/MS.Result(s)1.Morris water maze test showed that in the five-day positioning navigation test,from the third day of training,the time for mice in the BPS group to find the platform was longer than that of the control group.Compared to the BPS group,the BPS+PUE group was able to alleviate the delays from Day 4 onwards.In subsequent spatial probe tests,the number of entering the target quadrant in the BPS group was decreased,and the latency for entering the target quadrant was prolonged,whereas the situation in the PUE+BPS group was significantly improved as compared with that in the BPS group.In OFT,BPS-treated mice exhibited increased quiescent time and decreased total distance compared to controls,while BPS-induced increases in quiescent time and decreased total distance were improved by PUE administration.2.H&E staining showed that,compared with the control group,the pyramidal cell layer in hippocampal CA1 region of BPS group was significantly reduced and the cell morphology changed,and the granular cell neurons in DG region tended to be scattered and irregularly arranged.The above histological changes were improved in the PUE+BPS group as compared with the BPS group.Compared with the control,the BPS group reduced the expression of synaptic-related genes and proteins SYN1,SYP,and PSD-95 in the hippocampus,and inhibited the expression of BNDF,Trk B,and CREB genes and proteins.Compared with the BPS group,the PUE+BPS group restored the expression of synapse-related genes and proteins SYN1,SYP,and PSD-95 in the hippocampus,and up-regulated the expression of BNDF,Trk B,and CREB genes and proteins.3.Compared with the control group,PAS and H&E staining showed that there were fewer goblet cells in the colon,fewer glycoproteins secreted by the goblet cells and extensive infiltration of inflammatory cells in the BPS group.Compared with the BPS group,the colonic mucosal injury in the PUE+BPS group was improved.Compared with the control group,the mucosal barrier related indicators ZO-1,OCLN and CLD1 in the BPS group were significantly decreased,and compared with the BPS group,the mucosal barrier related indicators in the PUE+BPS group were restored.Compared with the control group,colonic inflammation-related indicators such as IL-1β,IL-6,IL-8,IL-17 A,TNF-αand IFN-γ were significantly increased in the BPS group.Compared with the BPS group,colonic inflammation-related indicators in the PUE+BPS group were down-regulated.4.Detection of 16 S rDNA intestinal flora showed that at the phylum level,Bacteroides and Sclerotinia were the most important phylum in the colonic mucosal tissues of the three groups of mice,followed by Proteus.BPS exposure increased the abundance of Sclerotinia in mice and decreased the abundance of Bacteroides.At the genus level,the relative abundance of clostridium Xl Va in the BPS group was increased.The flora of PUE+BPS group was closer to that of the control group than that of BPS group.SCFA analysis by UHPLC-MS/MS showed significantly lower concentrations of acetic acid,propionic acid,butyric acid,isobutyric acid,and isovaleric acid in the BPS group compared to the control group.At the same time,PUE reversed the decreases in acetic acid and propionic acid caused by BPS.Conclusion(s)1.BPS exposure changed the structure and morphology of hippocampus in mice,resulting in decreased synaptic plasticity and inhibition of BDNF-Trk B-CREB signaling pathway,resulting in abnormal neuroethology and neurotoxicity.2.BPS exposure induces decreased colonic mucosal integrity and mucosal barrier function in mice,inducing intestinal inflammation and flora imbalance,as well as decreased SCFA content.3.PUE can alleviate the neurotoxicity induced by BPS through the intestine-brain axis by improving intestinal permeability,repairing mucosal barrier,controlling colon inflammation,alleviating flora disorder,and recovering the content of SCFA.