肝硬化食管胃底静脉曲张患者口腔和肠道菌群变化

Changes of oral and gut microbiota in patients with cirrhosis and esophagogastric varices

目的分析健康人群和肝硬化食管胃底静脉曲张患者口腔和肠道菌群的不同,探讨口腔菌群与肠道菌群的关系。方法收集15例健康志愿者(HC组)和17例肝硬化食管胃底静脉曲张患者(CEGV组)的唾液和粪便标本,提取细菌DNA进行16S rRNA基因文库制备,对结果进行OTU聚类、物种分析、组成分析、差异性分析和多样性分析。结果HC组和CEGV组口腔和肠道菌群门水平和属水平部分菌属构成丰度具有明显差异性(P<0.05),2组口腔中优势菌属均为拟杆菌门下的普氏菌属,CEGV组肠道菌群中优势菌群是拟杆菌属而HC组是普氏菌属;HC组口腔、肠道菌群Alpha多样性较CEGV组高,但差异无统计学意义(P>0.05);Venn图显示2组口腔和肠道菌群共有73个物种,肠道菌群的物种数目要多于口腔菌群,富集于口腔内的奈瑟菌属、卟啉单胞菌属等在CEGV组肠道菌群中被检测出,而在HC组肠道中存在很少。结论肝硬化食管胃底静脉曲张患者与健康人群口腔和肠道菌群在门、属水平部分菌属的相对丰度存在差异;肝硬化食管胃底静脉曲张患者口腔中的微生物可能向肠道中转移。

Objective To explore the differences in oral and gut microbiota between healthy population and patients with cirrhosis and esophagogastric varices,and to identify the correlation between oral microbiota and gut microbiota in the latter population.Methods Saliva specimens and feces specimens were collected from 15 healthy volunteers(HC group)and 17 patients with cirrhosis and esophagogastric varices(CEGV group).Bacterial DNA was extracted and subjected to 16S rRNA gene sequencing.Operational taxonomic unit(OTU)clustering,species analysis,composition analysis,differential expression analysis and diversity analysis were performed.Results There were significant differences in the composition abundance of some oral and gut microbiota at phylum and genus level between HC group and CEGV group(P<0.05).Prevotella species,related to Bacteroides were the dominant oral bacteria in both groups,and Bacteroides and Prevotella were the dominant gut bacteria in CEGV group and HC group,respectively.Alpha diversity of oral and gut microbiota in HC group was higher than that in CEGV group,although no significant difference was detected(P>0.05).The Venn diagram showed that there were 73 species of oral and gut microbiota in the two groups,and species of intestinal microbiota were much abundant than those of oral microbiota.Neisseria and Porphyromonas,which were often enriched in the oral cavity,were detected in the intestinal microbiota of CEGV group,but few were found in the gut microbiota of HC group.Conclusion There are differences in the relative abundances of some bacteria at phylum and genus level in oral and intestinal microbiota of patients with cirrhosis and esophagogastric varices and healthy people.Oral microbiota in patients with cirrhosis and esophagogastric varices may migrate to the gut.