Analysis Of Intestinal Flora And Metabolomics Of Pregnant Women With AIT In Early Pregnancy And Their Correlation With Changes In Thyroid Antibodies

Objective: Autoimmune thyroiditis is one of the common diseases of endocrinology.Its clinical features are positive thyroid peroxidase antibody(TPOAb)and/or positive thyroglobulin antibody(TgAb),some patients may have thyroid insufficiency at the same time.The positive rate of TPOAb and TgAb in women during childbearing period is 10-20%,which varies with different ethnic groups.Some studies have shown that thyroid autoimmunity has a certain correlation with pregnancy-induced hypertension,miscarriage,placental abruption,premature birth and other pregnancy diseases and the higher incidence of adverse birth outcomes.Bacteria,viruses,protozoa and fungi together form the intestinal microbiota,forming a complex and huge microbial ecosystem.There is evidence that autoimmune thyroid disease may be related to changes or imbalances in the composition of the gut microbiota.Metabolomics can qualitatively quantify small molecular metabolites in biological samples,and is an important part of systems biology in the post-gene era.Collaborative multi-omics analysis is one of the hot spots in recent years.A small number of previous studies only explain the difference in the distribution of intestinal flora between AIT population and normal population.There has not been a multi-omics joint analysis of whether the intestinal flora or its metabolites are involved in the pathogenesis of AIT and its effect on the level of thyroid autoantibodies during pregnancy.Impacts and potential mechanisms,it is therefore necessary to further carry out multi-omics joint analysis of AIT population.In this study,firstly based on a large sample of pregnant natural population research cohort,we screened suitable research populations,analyzed the distribution of AIT intestinal flora in early pregnancy by 16 s rDNA sequencing,explored whether there are abnormalities in the structure of AIT intestinal flora during pregnancy,and analyzed the difference of bacteria The correlation between population and changes in thyroid autoantibody levels and its possible mechanism.Then analyze the differences in AIT stool metabolomics of the same batch of samples in early pregnancy and their relationship with changes in thyroid autoantibody levels,and analyze the different metabolites and related metabolic pathways that may affect the levels of thyroid autoantibodies.Finally,analyze the above-mentioned differences in serum metabolomics of pregnant women in the first trimester,and correlate them with the results of fecal 16 s rDNA sequencing and metabolomics,and explore the related metabolic pathways that may affect the level of thyroid autoantibodies.Methods:1.Based on the maternal-fetal-child-adolescent cohort study in the Northeast region,30 healthy pregnant women and 26 AIT pregnant women with matching age and BMI were selected in the early pregnancy,and the V4 region of the 16 S rDNA of the above-mentioned pregnant women’s stool samples were analyzed through the Illumina Mi Seq sequencing platform.High-throughput sequencing analysis.Bioinformatics was used to analyze the correlation between the difference in bacterial flora and environmental factors in the stool samples of the two groups of people.2.Using high performance liquid chromatography-mass spectrometry technology to conduct metabolomics research on stool samples of 30 healthy pregnant women and26 pregnant women with AIT,analyze the difference metabolites between the two,and look for the AIT pregnant population compared with the normal pregnant population Abnormal metabolic pathways,combined with the 16 s rDNA species distribution characteristics of AIT early pregnancy feces,explore biomarkers related to autoimmune thyroiditis during pregnancy,from the metabonomics level to diagnose and treat AIT diseases during pregnancy and changes in thyroid autoantibody levels The observations provide new directions for exploration.3.Analyze the metabolomics of serum samples of 30 healthy pregnant women and 26 pregnant women with AIT by high performance liquid chromatography-mass spectrometry technology to find the difference metabolites between the two,and look for abnormalities in the AIT pregnant population compared with the normal pregnant population Metabolic pathway,combined with the 16 S rDNA and metabolomics characteristics of AIT fecal specimens in early pregnancy,explore the related mechanisms of AIT disease and changes in thyroid autoantibody levels during pregnancy.Results:1.There are differences in the distribution of intestinal microbes between pregnant women with AIT and healthy pregnant women in the first trimester.At the level of species taxonomy,the species abundance of Firmicutes and Verrucomicrobia in early pregnancy with AIT is higher than that of healthy pregnant women,while the species abundance of Bacteroides,Proteobacteria and Actinomycetes is lower than that of healthy pregnant women;in species At the level of taxonomic genus,the species abundance of Faeculus,Rosea,Oncoccus and Mitsuoka in AIT pregnant women in early pregnancy is higher than that of healthy pregnant women,while Bacteroides,Prevotella,and Clostridium are more abundant.The abundance of species of the genus and Parabacteroides is lower than that of healthy pregnant women.2.Significant difference analysis found that the abundance of Microbacteria,Rosella,and Micrococcaceae in AIT pregnant women in early pregnancy was significantly lower than that in healthy pregnant women,while Rhodospirillum,Rhodospirillum and α-Proteobacteria were abundant.The degree is significantly higher than that of healthy pregnant women.3.The abundance of Enterobacteriaceae,Enterobacteriaceae,and Escherichia-Shigella species in the intestinal microbes of AIT pregnant women with a higher degree of TgAb decline in the third trimester than in the early trimester of pregnancy,while the abundance of Faecoccus species Decrease;AIT pregnant women with a higher degree of TPOAb decline in the third trimester than in the early trimester of pregnancy,the abundance of Rumenococcus and Proteobacteria species in the intestinal microbes in the early pregnancy.4.Serum TgAb levels of pregnant women with AIT in early pregnancy are negatively correlated with the species abundance of intestinal microbes Coprobacter,Tycoccus and Odobacter in the early pregnancy,and positively correlated with the species abundance of aminococcus acidis;serum TPOAb levels of pregnant women with AIT in early pregnancy are positively correlated with their early pregnancy The species abundance of intestinal microbes Macrococcus and Enterococcus was negatively correlated,but positively correlated with the species abundance of Bacillus,Blastomyces,Dallella,and Clostridium.5.The fecal metabolism patterns of pregnant women with AIT in early pregnancy and healthy pregnant women are different.KEGG pathway analysis found that there are four significantly different metabolic pathways in the two groups of pregnant women.Among them,the arachidonic acid pathway and serotonin are compared between pregnant women with AIT in early pregnancy and healthy pregnant women.Arachidonic acid,thromboxane B2,prostaglandin B2,prostaglandin F2 alpha and prostaglandin D2 are down-regulated in the synaptic pathway;Traumatic acid and13(S)-HOTr E are down-regulated in the α-linolenic acid metabolic pathway;in the bile secretion metabolic pathway Deoxycholic acid,prostaglandin F2 alpha,vabain and chenodeoxycholic acid were down-regulated.6.In the fecal arachidonic acid metabolism pathway of AIT pregnant women in early pregnancy,the down-regulation of arachidonic acid,thromboxane B2,prostaglandin B2,prostaglandin F2 alpha,and prostaglandin D2 may be related to the intestinal microbial Bacteroides and Bacteroides of AIT pregnant women in early pregnancy.The decrease in the abundance of Prevotella is related.7.There are differences in blood metabolism between pregnant women with AIT in early pregnancy and healthy pregnant women.KEGG pathway analysis found that there are 8 significantly different metabolic pathways in the two groups of pregnant women.Among them,pregnant women with AIT in early pregnancy have taurine and hypotaurine compared with healthy pregnant women.Glutamate in the acid metabolism pathway is up-regulated,and sulfoacetate is down-regulated;cis-aconitic acid is up-regulated in the citric acid cycle,glyoxylic acid and dicarboxylic acid metabolism pathways,and α-ketoglutarate is down-regulated;dihydroxy acid metabolism pathways are cis Aconitic acid is up-regulated,L-methionine is down-regulated;in the degradation of valine,leucine,isoleucine and propionic acid metabolism pathway,methylmalonic acid is up-regulated;D-glutamine and D-glutamate metabolism Α-ketoglutarate is down-regulated in the pathway;L-methionine is down-regulated in the folate metabolism pathway.8.Up-regulation of blood metabolite glutamate in pregnant women with AIT in early pregnancy may affect thyroid autoimmunity;down-regulation of α-ketoglutarate and up-regulation of cisaconitic acid may reflect the abnormality of tricarboxylic acid circulation in pregnant women with AIT during pregnancy.A sharp drop in TgAb during pregnancy may have a beneficial effect on the reduction of blood uric acid in pregnant women with AIT.Conclusions:1.The intestinal flora of the AIT population and the healthy group are different at different levels,and the difference in the flora may be related to the occurrence of AIT in early pregnancy.Changes in thyroid autoantibody levels may be affected by the abundance of multiple flora.2.Compared with healthy pregnant women,the stool metabolomics and blood metabolomics of pregnant women with AIT in early pregnancy have found abnormal metabolic pathways.The down-regulation of arachidonic acid pathway in stool metabolomics may be affected by the intestinal microbe Bacteroides in AIT pregnant women in early pregnancy The effect of reduced abundance of genus and Prevotella.