Research On The Pathogenic Mechanisms Of The Crosstalk Network Between Gut Microbiota And MiR-122-5p In Type 2 Diabetes Mellitus

ObjectiveType 2 Diabetes Mellitus(T2DM)is the most common public health problem in China.Recent studies have shown that T2DM patients have specific changes of the Gut Microbiota and Micro RNAs,and also find that some intestinal microbiota and miRNAss could interact with each other in the course of pathogenesis.Therefore,the purpose of this experiment is to detect the composition and expression characters of gut microbiota and miRNAs in primary T2DM,to study the correlation between gut microbiota and circulatory miRNAs in the early stage of T2DM,and to explore the possible mechanism of gut microbiota-miRNAs crosstalk network involved in the regulation of glucose homeostasis and thus affecting insulin transmission related signaling pathway.In order to find early diagnostic indicators and theoretical basis of precision therapy of T2DM.MethodsOne case-control experiment was strictly implemented,this study recruited the groups of T2DM patients(n=30)and Normal Control(n=30),collected their fasting serum and fecal samples,and recorded the biochemical indexes such as fasting blood glucose,Hemoglobin A1c(Hb Alc),Total Cholesterol(TC),Triglyceride(TG),High Density Lipoprotein Cholesterol(HDL-C),Low Density Lipoprotein Cholesterol(LDL-C)and Fasting Serum Insulin(FINS).Using 16 Sr DNA sequencing technology to detect the 60 fecal samples,analyzing the variousness of intestinal microbiota in two groups,and screen the differential expression of miRNAs between the groups of T2DM patients(n=5)and Normal Control(n=5)by miRNAs microarray technology.This study combined bioinformatics and statistical methods to analyze the correlation and association between specifically changed intestinal microbiota and miRNAs expression.And then,16 S functional gene prediction analysis was implemented to predict relevant gut microbiota.For candidate miRNA,using Real-time technique quantitative Polymerase Chain Reaction to screen and verify them from 50 blood specimen.And implemented enrichment pathway analysis to predict relevant miRNAs.Results1.Compared with healthy controls,the biochemical indexes including the Body Mass Index(BMI),Hb Alc,FBG,TG,TC,LDL-C,FINS(P<0.001,P<0.001,P<0.001、P=0.0125,P=0.98,P<0.001,P=0.0013)were significantly increased,while the HDL-C was reduced(P=0.022).2.Newly diagnosed with T2DM patients have significantly changed intestinal microbiota structure and miRNAs expression characteristics,The richness and diversity of the gut microbiota was lower than the healthy people.Line Discriminant Analysis Effect Size analysis showed that there was a significant difference(p<0.05,|LDA|>4)in 13 intestinal bacteria between the two groups.Compared with normal control group,a total of expressions of 88 miRNAs were significantly downregulated,while 22 miRNAs were significantly upregulated in T2DM group.3.Some significantly changed of intestinal flora and miRNAs between two groups had statistically significant correlations,in which significantly different count of the bacteriodes uniformis and phascolarctobacterium faecium(p=0.023,0.031)had negative correlation between the expression of plasma miR-122-5p(p=0.014,FC=-2.36)(r=-0.69,-0.60,p=0.01,0.01).4.The bioinformatics prediction of gut microbiota and miRNAs suggests that the gut microbiota-miRNAs crosstalk network may affect glucose uptake and regulate insulin signal transduction through target regulation of key genes of gluconeogenesis like Peroxisome Proliferator–activated Receptor gamma,PPAR gamma coactivativator-1 alpha and Human for Head Box O1,thus regulating the occurrence and development of T2DM.Conclusions1.We found that patients with newly diagnosed T2DM had high blood sugar,were easy to co-exist abnormal index of triglyceride and total cholesterol,combined with BMI index,showed that obesity and T2DM were directly related,and obesity was a predisposing factor for type 2 diabetes.Moreover,people with T2DM may be at risk of superinducing cardiovascular disease.2.T2DM patients hold their own distribution characteristics of gut microbiota.Based on the correlation between intestinal microbes and environmental factors(basic biochemical indexes),demonstrated that the dysregulation of gut microbiota is involved in the occurrence and development of T2DM.3.The miRNAs spectrum of the primary stage of T2DM was significantly changed,and the miR-122-5p in the plasma of the patients can be used as a potential molecular index for early diagnosis and accurate treatment of the T2DM.4.The expression level of miR-122-5p was negatively correlated with intestinal colonized bacterial count of the bacteriodes uniformis and phascolarctobacterium Faecium,combined with bioinformatics prediction,it is suggested that the crosstalk network of gut microbiota-miRNAs might play an authoritative role in regulating T2DM development by controlling key genes of gluconeogenesis during.