基于16S rDNA测序技术分析功能性便秘患者粪便菌群

Fecal flora in patients with functional constipation based on 16S rDNA sequencing technology

目的运用16S rDNA测序技术分析功能性便秘(FC)患者粪便菌群特征,以期寻找FC特征菌,为FC诊治寻找新的治疗靶点。方法收集福建中医药大学附属第二人民医院60例实验组(FC患者)和30例正常组的粪便,采用16S rDNA测序技术分析粪便菌群结构,并进行基因功能的预测。结果两组在门水平上,主要由厚壁菌门和拟杆菌门组成;在属水平上,主要优势菌以粪杆菌属和拟杆菌属为主。实验组粪便菌群丰富度指数Chao1、Observed_OTUs较正常组升高(P<0.05),多样性指数Shannon指数和Simpson指数虽有上升趋势,但差异无统计学意义(P>0.05)。布劳特菌属、罗氏菌属、Ruminococcus_gnavus_group、Ruminococcus_gauvreauii_group、Eubacterium_hallii_group、Anaerostipes、Lachnospiraceae_ND3007_group、Dorea、乳球菌属在实验组中丰度均显著降低(P<0.01)。实验组特征菌为小杆菌属,正常组为布劳特菌属和埃希菌−志贺菌属。实验组蔗糖降解Ⅲ(PWY-621)、丙酮酸发酵成乙酸和乳酸(PWY-5100)和琥珀酸发酵成丁酸盐(PWY-5677)功能下降(P<0.05)。结论功能性便秘患者主要表现为肠道菌群丰度与多样性升高,FC的发病可能与菌群结构发生改变有关。

Objective To analyze the characteristics of fecal flora in patients with functional constipation(FC)using 16S rDNA sequencing technology,with the aim of finding characteristic FC bacteria and new therapeutic targets for FC diagnosis and treatment.Methods Stool samples were collected from 60 FC patients(observation group)and 30 healthy individuals(normal control group)in our hospital.The structure of stool flora was analyzed using 16S rDNA sequencing technology,and the prediction of gene function was performed.Results At the phylum level,the dominant bacteria was Firmicutes and Bacteroidetes;at the genus level,the dominant genera were mainly Faecalibaterium and Bacteroides.The fecal flora richness indices Chao1 and Observed_OTUs were higher in the observation group than those in the normal group(P<0.05),while the diversity indices Shannon and Simpson showed an increasing trend compared with the normal group,with no statistically significant difference(P>0.05).Blautia,Roseburia,Ruminococcus_gnavus_group,Ruminococcus_gauvreauii_group,Eubacterium_hallii_group,Anaerostipes,Lachnospiraceae_ND3007_group,Dorea,and Lactococcus spp.were significantly(P<0.01)less abundant in the observation group.The biomarker of the observation group Dialister,and the normal group had Blautia and Escherichia-Shigella as the biomarker.The functional levels of sucrose degradation III(sucrose invertase,PWY-621),pyruvate fermentation to acetate and lactate(PWY-5100),and succinate fermentation to butyrate(PWY-5677)in FC patients decreased(P<0.05).Conclusions There were significant differences in the structure of fecal flora between the observation group and the normal control group,mainly in terms of elevated abundance and diversity.The pathogenesis of FC may be related to the microflora alteration.