Difference Of Gut Microbiota In Alzheimer’s Disease Patients Based On 16SrRNA Sequence Analysis

Background:Alzheimer’s disease(AD),the most common type of dementia,is a great burden to the patients and their families.However,there is no effective treatment plan at present,and all treatments only slow the progression of AD,not a cure.The main pathological mechanisms of AD are extracellular plaques composed of Amyloid beta(Aβ)and Neurofibrillary tangles(NFTs)mainly composed of Tau.However,no significant results have been reported for these two mechanisms.Little has been achieved,so we need new ideas to find better methods.Human intestinal flora is a complex microbial communities,the intestinal flora through the gut-brain axis with important influence on the central nervous system,such as emotion,cognitive function,but the interaction between gut microbes and the AD is still have differences,unclear may exist between the biomarkers,and the AD is a disease with gender differences,The prevalence of AD is different in different genders.At present,there are few studies on the differences of intestinal flora in patients with AD of different genders.Therefore,further studies should be conducted to find out.Purpose:To explore the differences in the abundance and composition of intestinal microorganisms between AD patients and the normal population,and analyse the differences in intestinal microorganisms between AD patients of different genders,To find the relevant changes in intestinal microorganisms in AD patients,so as to provide a new basis for the study of AD.Method:A total of 42 AD patients,including 15 males and 27 females,were enrolled as the AD group in the mental health department of Zhejiang People’s Hospital.A total of 27 patients,including 9 males and 15 females,were selected as the control group.DNA was extracted from the collected fecal samples and analyzed by microbial 16 SrRNA gene sequencing.Result:1.The diversity and abundance of gut microflora in AD group were higher than those in normal control group(P<0.05)。2.There were significant differences in class,order,family and genus between AD group and control group,and the differences were statistically significant(P<0.05).Turicibacterales,Campylobacterales and Oceanospirillales in the order level;In families with abundance greater than 0.1%,the abundance of unidentified Clostridiales and Alcaligenaceae in AD group was higher than that in control group,while the abundance of Peptostreptococcaceae and Veillonellaceae in control group was higher.At the genus level where the abundance of intestinal microorganisms was greater than 0.1%,we found that the abundance ratio of AD group in unidentified Clostridiales,Oscillospira,Coprobacillus and Sutterella was higher than HC group,while in Megamonas,the content of HC group was higher,and there was also a statistical difference between AD group and control group in Haemophilus.3.In the AD group,there were statistically significant differences in gender,especially in the level of intestinal flora(P<0.05): Prevotella,Megamonas,Victivallaceae,Sutterella,Alcaligenaceae,Oxalobacteraceae.4.There were statistically significant differences between age,family history and intestinal microbial diversity in AD patients(P<0.05).Conclusion:There were significant differences in the abundance and composition of intestinal flora between AD patients and healthy controls,and there were also significant differences in the composition of intestinal flora among AD patients with different genders.The intestinal flora provides new ideas for the diagnosis and treatment of AD.