Multiomics Study On Intestinal Microbiota And Metabolism Of Patients With Peutz-Jeghers Syndrome

BackgroundPeutz-Jeghers Syndrome(PJS)is a rare genetic disease,characterized by pigmentation of the skin and mucosa,multiple hamartomatous polyps of the gastrointestinal tract,and increased susceptibility of multisystem cancer.In addition to heredity,intestinal microenvironment is the most important and complex microbial dynamic system in the human gut,and its changes may have an impact on PJS.At present,it is not clear whether the imbalance of intestinal flora is related to PJS,however,intestinal flora is a new focus of current research,and it plays a crucial role in maintaining a dynamic balance.In order to further understand the role of intestinal flora in the pathophysiology of PJS and to search for new screening and treatment methods,further exploration of the complex intestinal microbial community of PJS patients is necessary.However,intestinal flora includes not only intracaval flora but also intestinal mucosal associated microbiota.Currently,most studies understand intracaval flora through fecal microbiota analysis,while there are few reports about mucosal associated microbiota on small intestine,which may due to the difficulty of collecting large amounts of small intestinal by enteroscopy.Since intestinal mucosal related microbiota has a more direct impact on host,and intestinal mucosal epithelium and intestinal cavity environment are also quite different,the study on intestinal mucosal related microbial community is of great significance.Liquid chromatography-tandem mass spectrometry(LC-MS)can detect alterations of metabolites,to study the metabolic pathway of PJS intestinal bacteria biological system,we hope that we will find key metabolites and special related metabolic pathways in PJS,explore changes in intestinal flora or abnormal metabolites of PJS patients,to provide basis for indepth understanding of PJS.AimThe purpose of this study was to evaluate the structure and composition of intestinal fecal flora,including bacteria and fungi,and mucosal microbiota in patients with PJS,and to explore the potential influence of intestinal microbiota disorders and metabolites changes on PJS.MethodsThe bacterial and fungal composition of the fecal microbiota was analyzed in 23 patients with PJS(cases),17 first-degree asymptomatic relatives(ARs),and 24 healthy controls(HCs)using 16S and ITS2 sequencing for bacteria and fungi,respectively.Differential analyses of the intestinal flora were performed from the phylum to species level.A total of 13 PJS patients and 12 healthy controls were included in the second part.The 16SrRNA gene sequencing was conducted on the small intestinal mucosa,to compare the changes of diversity and abundance in bacterial flora between the two groups.Moreover,LC-MS was used to study the differential metabolites of PJS patients and healthy controls and found different metabolites and metabolic biomarkers of small intestinal mucosa samples.Based on the results of microbial diversity and untargeted metabolomics,analyze comprehensively the correlation of microorganisms and metabolites between PJS patients and healthy controls.ResultsAlpha-diversity distributions of bacteria and fungi indicated that the abundance of both taxa differed between PJS cases and controls.However,while the diversity and composition of fecal bacteria in PJS cases were significantly different from those in ARs and HCs,fungal flora was more stable.High-throughput sequencing confirmed the special characteristics and biodiversity of the fecal bacterial and fungal microflora in patients with PJS.They had lower bacterial biodiversity than controls,with a higher frequency of the Proteobacteria,Enterobacteriaceae,and Escherichia-Shigella,and a lower frequency of the Firmicutes phylum.The abundance of intestinal mucosal microflora was significantly lower than fecal microflora,and the bacterial diversity of PJS patients was lower than that of controls,but there was no statistical significance.In addition,the small intestinal mucosa of PJS patients showed metabolic substances changed a lot.Lipid metabolism,amino acid metabolism,carbohydrate metabolism,nucleotide metabolism and other pathways were significantly different from those of healthy controls.ConclusionThe findings reported here confirm gut microbiota flora and metabolic disorders in patients with PJS.This is the first report on the bacterial and fungal microbiota,mucosal flora and metabolites profile of subjects with PJS,which may be meaningful to provide a structural basis for further research on intestinal microecology in PJS.