ABSTRACT
OBJECTIVES@#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 1 491. There were 169, 221, and 192 kinds of OTUs unique to the CI-T2DM, CI, and control group, respectively.@*CONCLUSIONS@#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.