Root-Securing And Brain-Fortifying Decoction On Intestinal Microflora And C/EBPβ/AEP Signaling Pathway In AD Rats

Objective:To explore the effect of Root-Securing and Brain-Fortifying decoction on THE C/EBPβ/AEP signaling pathway by regulating the intestinal flora of AD rats.Methods:50 MALE SD rats were randomly divided into 5 groups,including normal group,model group,Root-Securing and Brain-Fortifying decoction high-low dose group（hereinafter referred to as gugao and gulow group）and probiotic group,with 10 rats in each group.AD model was established by injecting Aβ_25-35into the hippocampus of both the model group and the treatment group.From the 4th day after modeling,gu high group and gu low group were given Root-Securing and Brain-Fortifying decoction by intragastric administration,while probiotics group was given bifidobacteria triplex viable tablets by intragastric administration.After continuous intragastric administration for 8 weeks,the spatial memory ability of rats was detected by water maze test.The distribution and quantity of Ni’s corpuscles were detected by Ni’s staining.HE staining was used to detect the number and morphology of neurons in each group.Western blot was used to detect the expression of C/EBPβ/AEP signaling pathway proteins in hippocampus,including C/EBPβ,P-C/EBPβand AEP.16Sr RNA was used to detect the abundance and diversity of microflora at phylum and genus level.Results:Water maze test confirmed that in the directional navigation test,the escape latency of rats in normal group was significantly shorter than that in model group（P<0.05）,and the escape latency of rats in model group was significantly longer than that in solid high group,solid low group and probiotic group（P<0.05）,and the movement trajectory was chaotic.In the space exploration experiment,compared with the normal group,the number of rats crossing the target quadrant platform in the model group was significantly reduced（P<0.05）,while the number of rats crossing the target quadrant platform in the drug administration groups was significantly increased compared with the model group（P<0.05）.The results of Nissl staining showed that the nuclei of normal group were complete and neatly arranged,and the number of neuron nissl was abundant.In the model group,the nuclei were broken and scattered,and the number of nite in the cells was rare.Compared with model group,the number of neuron cells in probiotic group,solid high group and solid low group was less damaged,the morphology of cell nucleus was significantly improved,and the arrangement of nite was relatively orderly,uniform and compact.HE staining showed that the number of hippocampal neurons in the normal group was the largest and the morphology was complete,while the number of hippocampal neurons in the model group was significantly reduced and the arrangement was sparse and scattered.Compared with the model group,the number of neurons in all treatment groups was increased and the arrangement of neurons was relatively neat and uniform.Western blot showed that the expression levels of three proteins in the normal group were lower than that in the model group（P<0.05）.Compared with the model group,the expression levels of C/EBPβ,P-C/EBPβand AEP in the solid high group,solid low group and probiotic group were all decreased（P<0.05）.It was confirmed by 16Sr RNA assay that the diversity and richness of microbial species were revealed by Alpha diversity analysis of Shannon curve,dilution curve,Rank abundance curve and species accumulation curve.Desulfobacterota abundance in the model group is higher than that in the blank group and the drug group at phylum level,and at the genus level,compared with that in the drug group,The abundance of Turicibacte-R and Blautia in the model group was relatively decreased（P<0.05）,while the abundance of Turicibacte-R and Blautia in the model group was relatively decreased（P<0.05）.The relative abundance of Lachn-Ospiraceae NK4A136 Group,Colidextribacter and Desulfovibrionaceae in the model group was increased（P<0.05）.Conclusion:Root-Securing and Brain-Fortifying decoction can improve the learning and memory ability induced by Aβ25-35 in AD rats,and the mechanism may be related to the regulation of intestinal flora and the"gut-brain axis"mechanism,thus inhibiting the expression of C/EBPβ/AEP signaling pathway.