An Integrated Multicenter Amplicon Sequencing Data Reveals New Evidence of the Interaction Between the Gut Microbiota and Irritable Bowel Syndrome

Abstract

Background Gut dysbacteriosis has been reported as one of the etiologies for irritable bowel syndrome (IBS). However, the association between gut microbiota and IBS is still inconclusive. The study aims to provide new evidence of the interaction between the gut Microbiota and IBS. Method A paired-sample study was designed by retrieving original multicenter 16s-rRNA data of IBS patients and healthy controls from the GMrepo database. The propensity score matching (PSM) algorithm was applied to reduce confounding bias. The differential analysis of microbiota composition was performed at different taxonomic levels. The co-occurrence network was established. Subgroup analysis was performed to identify specific microbial compositions in different IBS subtypes. Results A total of 1522 amplicon samples were initially enrolled. After PSM, 708 samples (354 IBS and 354 healthy individuals) were eligible for further analysis. A total of 1,160 genera were identified. We identified significantly changed taxa in IBS groups (IBS-enriched: the families Enterobacteriaceae, Moraxellaceae, and Sphingobacteriaceae; the genera Streptococcus, Bacillus, Enterocloster, Sphingobacterium, Holdemania, and Acinetobacter. IBS-depleted: the phyla Firmicutes, Euryarchaeota, Cyanobacteria, Acidobacteria, and Lentisphaerae; the families Bifidobacteriaceae, Ruminococcaceae, Methanobacteriaceae, and the other 25 families; the genera Faecalibacterium, Bifidobacterium, and other 68 genera). In subgroup analysis, we profiled microbial compositions in IBS with predominant diarrhea and constipation. We further identified the genera Bilophila and Enterocloster that may be involved in linking IBS with psychiatric disorders. The co-occurrence network identified three hub genera and six hub species (including Faecalibacterium prausnitzii) that may be important in IBS pathophysiology. Strong positive interactions were identified among the Bifidobacterium longum, Bifidobacterium breve, and Bifidobacterium adolescentis in the Bifidobacterium community. Conclusion This study provides updated evidence in identifying specific microbes that may involve in IBS pathogenesis. Future modalities may be further validated by targeting these microorganisms.