Integrated Metabolomics And 16s RDNA Sequencing Technology To Explore The Complex Mechanism Of Ganmaidazao Decoction Against Alzheimer’s Disease

Objective: Alzheimer’s disease is a common neurodegenerative disease,and due to its complex etiology,lack of drugs that can be used to diagnose,relieve symptoms of Alzheimer’s disease,improve prognosis and that can be used for a long time with few side effects,has become a serious influence on the quality of life of the elderly disease.Studies have shown that traditional Chinese medicine targeting gut flora have potential therapeutic effects on alleviating the clinical manifestations of Alzheimer’s disease,in which intestinal metabolites are considered to be the bridge of communication between the brain-gut axis.In our previous study,we found that Chinese herbal compound Ganmaidazao Decoction was effective in alleviating cognitive dysfunction in Alzheimer’s disease.Therefore,this study first explored the distribution of components in the body after administration of Ganmaidazao Decoction,and then explored the molecular mechanism of Ganmaidazao Decoction against Alzheimer’s disease by integrating 16 S r DNA high-throughput sequencing technology and metabolomics technology.Methods:(1)Ultrahigh liquid chromatography quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF/MS)and UINIFI software were used to analyze and identify the distribution of main components in the blood and colon of rats after administration of Ganmaidazao Decoction.(2)Screening of differential flora and target bacteria of Ganmaidazao Decoction based on high-throughput sequencing microbiome method(16S r DNA sequencing).(3)Based on UPLC-Q-TOF/MS metabonomics technology combined with multivariate analysis method,stool metabolomics of rats were analyzed.(4)Spearman correlation analysis was used to analyze the relationship between differential microflora and differential metabolites.(5)The key pathways and targets of improving Alzheimer’s disease with Ganmaidazao Decoction were identified by PICRUSt 2 intestinal flora function prediction combined with fecal metabolomics results.Results:(1)Under positive mode,53 components were found in feces and 12 in plasma.Under negative mode condition,28 components were found in feces and 6 in plasma.(2)Ganmaidazao decoction improved the abundance and diversity of intestinal microflora in Alzheimer’s disease rats,and reversed the changes of fecal metabolites.Differential intestinal microflora was highly correlated with differential metabolites.(3)PICRUSt 2 predicts that phenylalanine metabolism may be a key metabolic pathway,and Ganmaidazao Decoction can reduce the accumulation of phenylalanine and secondary metabolite phenylpyruvate,and promote phenylalanine metabolism by restoring the activity of phenylalanine hydroxylase,a key enzyme in this pathway.Conclusion: This comprehensive multi-omics approach plays an important role in understanding the complex mechanism of Ganmaidazao Decoction in the treatment of Alzheimer’s disease,and adds new evidence to the application of traditional Chinese medicine in the treatment of neurodegenerative diseases.