关键词: 肠道菌群, 1型糖尿病, 儿童, 16SrRNA测序

Abstract: Objective To explore the characteristics of intestinal flora in children with type 1 diabetes mellitus (T1DM) by 16SrRNA gene sequencing method, and to compare the differences on gut microbiota between T1DM patients and healthy controls, so as to provide theoretical basis and evidence for clinical application of probiotics in early intervention for T1DM children. Methods A total of 18 children aged 5 to 14 years who were newly diagnosed with T1DM in the Department of Endocrinology and Metabolism, Kunming Children′s Hospital were enrolled in this study from October 2018 to October 2019.At the same time, 19 healthy children with similar gender and age were selected as controls.After collecting fresh stool samples from two groups, 16SrRNA gene sequencing experiments were performed, and QIIME 2 analysis processes were used for bioinformatics analysis.Then the marked differences of gut microbiota among two groups were compared. Results 1) Totally 3 248 Features with 100% similarity were obtained by using QIIME2 software.2) Most of intestinal bacteria were classified into genus and species after identification and annotation.3) Alpha diversity analysis showed that the sequencing depth was sufficient in this study.Moreover, the richness and diversity of gut microbiota in T1DM children were lower than those in healthy controls (P<0.05).4) In the analysis of beta diversity, the PCoA image indicated that the gut microbiota structure was different between T1DM group and healthy controls.5) At the level of phylum, the abundance of Actinobacteria, Bacteroidetes and Cyanobacteria was increased while the abundance of Proteobacteria and Patescibacteria was decreased in T1DM group(P<0.05).At the genus level, the abundance of Faecalibacterium, Bifidobacterium and Bacteroides was increased in T1DM group, but the abundance of Escherichia_Shigella, Enterococcus and Blautia was reduced (P<0.05). Conclusions The ecology of gut microbiota is imbalanced in T1DM children.Compared with healthy children, the richness and diversity are notably lower in T1DM children as well.Moreover, there are obvious differences on the structure of gut microbiota between T1DM children and healthy children.

Key words: gut microbiota, type 1 diabetes mellitus, children, 16SrRNA sequencing