十二指肠球部和末端回肠黏膜菌群多样性分析

Mucosal microbiome diversity and composition in duodenal bulb and terminal ileum under normal and inflammatory conditions

目的分析十二指肠球部与末端回肠正常状态下黏膜菌群多样性,比较不同部位菌群组成情况。方法选择胃镜及肠镜检查的健康体检者各15例,分别钳取十二指肠球部和末端回肠黏膜组织,使用16S rRNA测序法对球部和末端回肠黏膜组织进行生物信息分析。另外又选取8例球炎患者和15例末端回肠炎患者进行对比分析。结果球部黏膜菌群测得个28个门,397个属。末端回肠黏膜测得25个门,344个属。两个部位在门水平上均以梭杆菌门、变形菌门、厚壁菌门、拟杆菌门、放线菌门为主要菌群,球部优势菌群所占比例依次为49.43%、25.93%、8.68%、5.19%、5.76%;末端回肠优势菌群比例依次为38.30%、29.61%、17.56%、8.15%、3.70%。属水平球部黏膜以鲸甘菌属、气单胞菌属、贪铜菌属、不动杆菌属、梭菌属为主要菌群,比例依次为49.38%、6.42%、5.62%、4.78%、3.84%;末端回肠黏膜以鲸甘菌属、贪铜菌属、气单胞菌属、拟杆菌属、不动杆菌属为主要菌群,比例依次为37.56%、12.83%、4.2%、3.84%、2.74%。球部正常黏膜与炎症状态菌群组成差异有统计学意义(P<0.05)。末端回肠正常黏膜与炎症状态菌群差异无统计学意义(P>0.05)。结论不同部位的肠道黏膜菌群分布存在差异,球部黏膜菌群比末端回肠黏膜菌群更多样。球部黏膜菌群失调参与炎症发生;末端回肠黏膜菌群在炎症状态下有轻微改变。

Objective To analyze the mucosal microbiome diversity and composition of duodenal bulb and terminal ileum under normal and inflamatory conditions. Methods Thirty healthy subjects were selected for gastroscopy(15) and colonoscopy(15), respectively, biopsy samples were taken from the duodenal bulb and terminal ileum and analyzed with 16 S rRNA sequencing. In addition, 8 patients with duodenal bulb inflammation and 15 patients with terminal ileum inflammation were also selected for comparative analysis. Results Twenty-eight phyla and 397 genera were detected in duodenal bulb;while 25 phyla and 344 genera were detected in terminal ileum. At the phylum level, Fusobacteria, Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were the most abundant communities of the two sites, the proportion of these dominant microflora in duodenal bulb was 49.43%, 25.93%, 8.68%, 5.19% and 5.76%, respectively;while in terminal ileum were 38.30%, 29.61%, 17.56%, 8.15% and 3.70%, respectively. At the genera level, Cetobacterium, Aeromo-nadaceae, Cupriavidus, Acinetobacter and Clostridium were the dominant microbies in duodenal bulb, accounting for 49.38%, 6.42%, 5.62%, 4.78% and 3.84% respectively;while Cetobacterium, Cupriavidus, Aeromonadaceae, Bacteroides and Acinetobacter were the dominant microbies in the terminal ileum, accounting for 37.56%, 12.83%, 4.2%, 3.84% and 2.74%, respectively. There was a statistically significant difference in the composition of bacterial flora between normal and inflammatory state in bulbous mucosa(P<0.05);while there was no significant difference between the normal and the inflammatory state in mucosa of terminal ileum(P>0.05). Conclusion The distribution of intestinal mircobiome is different in different parts of the intestine. The mucosal microbiome in duodenal bulb is more diverse than that in terminal ileum. The results indicate that the dominant species in duodenal bulbs differs between healthy subjects and patients with inflammation;the mucosal microbiome dysbiosis is involved in the development of duodenal bulb inflammation;while it might be associated with terminal ileum inflammation.