脑梗死合并2型糖尿病患者的肠道菌群特征

Characteristics of intestinal flora in patients with cerebral infarction complicated with Type 2 diabetes mellitus

目的:单纯性脑梗死(cerebral infarction,CI)和CI合并2型糖尿病(CI complicated with Type 2 diabetes mellitus,CI-T2DM)患者的肠道微生物特征尚不清楚。本研究旨在分析单纯CI患者和CI-T2DM患者肠道菌群的变化特征。方法:回顾性纳入2021年9月至2022年9月在莆田学院附属医院住院的患者,分为CI组(n=12)和CI-T2DM组(n=12),同时选择12名健康人作为对照组。从受试人群粪便标本中提取总DNA。通过Illumina Novaseq平台进行宏基因组测序。使用Knead Data、Kraken2和Bracken软件对测序结果进行分析。结果:在门水平,CI-T2DM组厚壁菌、拟杆菌和变形杆菌的平均比例分别为33.07%、54.80%和7.00%,CI组的分别为14.03%、69.62%和11.13%,对照组的分别为50.99%、37.67%和5.24%,其中厚壁菌在3组间的分布差异有统计学意义(F=6.130,P=0.011)。在科水平,与CI组相比,CI-T2DM组中真/优杆菌科的相对丰度(t=8.062,P<0.001)显著增加,而棒状杆菌科(t=4.471,P<0.001)、甲烷杆菌科(t=3.406,P=0.003)和假单胞菌科(t=2.352,P=0.028)的相对丰度显著减少。在属水平,与CI组相比,CIT2DM组中痤疮丙酸杆菌属(t=6.242,P<0.001)、真/优杆菌属(t=8.448,P<0.01)和黏液真杆菌属(t=3.442,P=0.002)的相对丰度显著增加;甲烷短杆菌属(t=3.466,P=0.002)、锥体杆菌属(t=2.846,P=0.009)和假单胞菌属(t=2.352,P=0.028)的分布显著减少。在种水平,与CI组相比,CI-T2DM组痤疮丙酸杆菌的相对丰度(t=6.242,P<0.001)显著增加,铜绿假单胞菌(t=2.352,P=0.028)显著减少。线性判别分析(linear discriminant analysis effect size,LEfSe)法表明:在属水平,CI-T2DM组和CI组之间的假单胞菌和黏液真杆菌属的分布差异最大。在种水平上,3组的操作分类单元(operational taxonomic units,OTU)总数为1491;CI-T2DM组、CI组和对照组分别有169、221和192种独特的OTU。结论:从门水平到种水平,CI-T2DM患者的肠道菌群组成均与单纯CI患者不同;与健康人群相比,厚壁菌门、拟杆菌门和变形菌门数量比例发生改变是CI与CI-T2DM患者肠道菌群失调的一个重要特征;单形拟杆菌、产丁酸盐菌差异分布需要引起重视。

Objective:The intestinal microbial characteristics of patients with simple cerebral infarction(CI)and CI complicated with Type 2 diabetes mellitus(CI-T2DM)are still not clear.This study aims to analyze the differences in the variable characteristics of intestinal flora between patients simply with CI and CI-T2DM.Methods:This study retrospectively collected the patients who were admitted to the Affiliated Hospital of Putian University from September 2021 to September 2022.The patients were divided into a CI group(n=12)and a CI-T2DM group(n=12).Simultaneously,12 healthy people were selected as a control group.Total DNA was extracted from feces specimens.Illumina Novaseq sequencing platform was used for metagenomic sequencing.The Knead Data software,Kraken2 software,and Bracken software were applied for sequencing analysis.Results:At phylum level,the average ratio of Firmicutes,Bacteroidetes,and Proteobacteria in the CI-T2DM group were 33.07%,54.80%,and 7.00%,respectively.In the CI group,the ratios of each were 14.03%,69.62%,and 11.13%,respectively,while in the control group,the ratios were 50.99%,37.67%,and 5.24%,respectively.There was significant differences in the distribution of Firmicutes(F=6.130,P=0.011)among the 3 groups.At the family level,compared with the CI group,the relative abundance of Eubacteriaceae(t=8.062,P<0.001)in the CI-T2DM group was significantly increased,while Corynebacteriaceae(t=4.471,P<0.001),Methanobacteriaceae(t=3.406,P=0.003),and Pseudomonadaceae(t=2.352,P=0.028)were decreased significantly.At the genus level,compared with the CI group,there was a relative abundance of Cutibacterium(t=6.242,P<0.001),Eubacterium(t=8.448,P<0.001),and Blautia(t=3.442,P=0.002)in the CI-T2DM group which was significantly increased.In terms of Methanobrevibacter(t=3.466,P=0.002),Pyramidobacter(t=2.846,P=0.009)and Pseudomonas(t=2.352,P=0.028),their distributions were decreased significantly in the CI-T2DM group.At the species level,compared with the CI group,the relative abundance of Cutibacterium acnes(t=6.242,P<0.001)in the CI-T2DM group was significantly increased,while Pseudomonas aeruginosa(t=2.352,P=0.028)was decreased significantly.Still at the genus level,linear discriminant analysis effect size(LEfSe)analysis showed that the distributions of Pseudomonas and Blautia were determined to be the most significantly different between the CI-T2DM and the CI group.At the species level,the total number of operational taxonomic units(OTUs)in the 3 groups was 1491.There were 169,221,and 192 kinds of OTUs unique to the CI-T2DM,CI,and control group,respectively.Conclusion:From phylum level to species level,the composition of intestinal flora in the patients with CI-T2DM is different from those in the patients simply with CI.The change in the proportion of Firmicutes,Bacteroidetes and Proteus compared with the healthy population is an important feature of intestinal flora imbalance in the patients with CI and with CI-T2DM.Attention should be paid to the differential distribution of Bacteroides monocytogenes and butyrate producing bacteria.