Alteration of Ascending Colon Mucosal Microbiota in Patients after Cholecystectomy

Abstract BACKGROUND Cholecystectomy is an effective therapy for gallstones, however, the incidence of CRC has increased significantly in post-cholecystectomy (PC) patients. Whether it is related to the changed mucosal microbiota in ascending colon is still unclear. AIM To explore the association between gut microbiota and cholecystectomy. METHODS Mucosal biopsy samples were collected from 30 PC patients (the test group) with gallbladder stones and 28 healthy individuals (the control group) by colonoscopy. Subsequently, the test group was subdivided into the YMA group or SNR group(age over or under 60), DG group or NG group (with or without diarrhea) and Log group or Sht group(duration over or under 5 years) according to patients’ clinical characteristics. 16S-rRNA gene amplicon sequencing was performed and alpha diversity, beta diversity and composition analysis were determined. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States based on the Kyoto Encyclopedia of Genes and Genomes database was used to predict the function of the microbiome. RESULTS The PC patients showed similar richness and overall composition with healthy controls, but PC patients over 60 years showed a different structure than those under 60 years. At the phylum level, the richness of Bacteroidetes was significantly higher in PC patients. Similarly, the genus Bacteroides , Parabacteroides and Bilophila were remarkably more abundant in PC patients compared with the controls. In addition, the PC patients had significant enrichments in both metabolic pathways, including Lipopolysaccharide and vancomycin group antibiotics biosynthesis compared to the controls. CONCLUSION Our study suggested that mucosal microbiota was changed in PC patients, which may reveal new insight into therapeutic options for colorectal cancer and diarrhea after cholecystectomy.