Effect Of Xixin Decoction On Neuroinflammation Level And Intestinal Flora In AD Model Rats

ObjectiveTo explore the effects of Xixin Decoction on the spatial learning and memory ability,neuroinflammatory response-related protein expression and the structure of intestinal flora in AD model rats,and to explore the possible mechanism of Xixin Decoction on the prevention and treatment of AD disease from the brain-gut axis vision.Methods（1）Forty-eight healthy SPF male rats were randomly divided into sham operation group,model group,Anlishen group,Xixintang group,with 12 rats in each group.In addition to the sham operation group,the rats in the other groups were given the same amount of normal saline,and the rats in the other groups were injected intraperitoneally with D-galactose combined with bilateral ventricular injection of Aβ_25-35to establish an AD model.The rats in the other groups were given intragastric administration for 4 weeks.（2）Morris water maze experiment was used to observe the spatial memory ability of rats in each group.（3）HE staining to observe the pathological changes of rat brain tissues in different groups.（4）The expression of Aβ_1-42,GFAP and IBA-1 in the hippocampus of brain tissue were detected by immunohistochemistry and western blotting respectively.（5）ELISA method to detect the expression levels of TNF-α,IL-1βand IL-10 in the hippocampus.（6）Using 16s rRNA technology to detect changes in the structure of the intestinal flora of each group.Results（1）The results of the Morris water maze experiment showed that compared with the sham operation group,the escape latency of rats in the model group was significantly prolonged（p<0.01）,the stagnation time of the platform quadrant and the number of entry into the effective area were significantly reduced（p<0.01）,compared with the model group In the Xixintang group,the escape latency time was shortened（p<0.01）,the stagnation time in the platform quadrant and the number of entry into the effective area increased（p<0.05,p<0.01）.（2）The results of HE staining showed that compared with the sham operation group,the hippocampus tissue cells in the model group were stained more deeply,the number of vertebral nerves was less,the cell bands were arranged disorderly and sparsely,there were neuron loss,free cells,cell cavities,and no cell bodies.Morphological changes such as rules;compared with the model group,the cell morphology of the treatment group was roughly normal,the neuron cells were arranged more neatly,and the cell cavities were reduced.（3）The results of immunohistochemistry showed that compared with the sham operation group,the expression levels of Aβ_1-42,GFAP and IBA-1 in the hippocampus of the model group increased（p<0.01）.Compared with the model group,the protein expression of Aβ_1-42,GFAP and IBA-1 in the hippocampus of Xixintang group decreased（p<0.01）.（4）Western blot results showed that compared with the sham operation group,the expression levels of GFAP and IBA-1 in the hippocampus of the model group increased（p<0.01）.Compared with the model group,the expression of GFAP and IBA-1 protein in the hippocampus of Xixintang group decreased（p<0.01）.（5）The ELISA method showed that compared with the sham operation group,the levels of IL-1βand TNF-αin the hippocampus of the model group increased（p<0.01）,and the content of IL-10 decreased（p<0.01）;compared with the model group Compared with,the levels of IL-1βand TNF-αin the hippocampus of rats in the Xixintang group were decreased（p<0.01）,and the content of IL-10 was significantly increased（p<0.01）.（6）The 16s rRNA test results showed that compared with the sham operation group,the model group had more abundant Bacteroides in the intestines,and weakened the abundance of Firmicutes and Proteobacteria.Compared with the model group,the abundance of bacteria in the posterior intestinal wall of rats in the Xixintang group increased,while the abundance of Bacteroides and Proteobacteria decreased.Conclusion（1）Xixin Decoction can improve the learning and memory ability of D-gal combined with hippocampal Aβ_25-35AD model rats to a certain extent,and reduce the hippocampal Aβplaque deposition and pathological changes.（2）Xixin Decoction can down-regulate the expression of inflammatory proteins GFAP and IBA-1 in the hippocampus of AD model rats,down-regulate the levels of pro-inflammatory factors IL-1βand TNF-α,and up-regulate the levels of anti-inflammatory factor IL-10,thereby inhibiting Inflammation,play an anti-inflammatory and neuroinflammation protection.（3）Xixin Decoction can reversely adjust the microflora structure of the intestinal flora of AD model rats to a certain extent,and adjust the imbalance of intestinal microecology.