I Rangel1, J Sundin1, S Fuentes2, D Repsilber1, W M de Vos2,3, R J Brummer1. 1. School of Health and Medical Sciences, Örebro University, Örebro, Sweden. 2. Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands. 3. Departments of Bacteriology & Immunology and Veterinary Biosciences, University of Helsinki, Helsinki, Finland.
Abstract
BACKGROUND: The faecal-associated microbiota is commonly seen as a surrogate of the mucosal-associated microbiota. However, previous studies indicate that they are different. Furthermore, analyses of the mucosal microbiota are commonly done after standard bowel cleansing, affecting the microbial composition. AIM: To compare the mucosal-associated microbiota, obtained from unprepared colon, with faecal-associated microbiota in healthy subjects and irritable bowel syndrome (IBS) patients. METHODS: Faecal and mucosal biopsies were obtained from 33 IBS patients and 16 healthy controls. Of IBS patients, 49% belonged to the diarrhoea-predominant subgroup and 80% suffered from IBS symptoms during at least 5 years. Biopsies were collected from unprepared sigmoid colon and faecal samples a day before colonoscopy. Microbiota analyses were performed with a phylogenetic microarray and redundancy discriminant analysis. RESULTS: The composition of the mucosal- and the faecal-associated microbiota in unprepared sigmoid colon differs significantly (P = 0.002). Clinical characteristics of IBS did not correlate with this difference. Bacteroidetes dominate the mucosal-associated microbiota. Firmicutes, Actinobacteria and Proteobacteria dominate the faecal-associated microbiota. Healthy subjects had a significantly higher (P < 0.005) abundance (1.9%) of the bacterial group uncultured Clostridiales I in the mucosal-associated microbiota than IBS patients (0.3%). Bacterial diversity was higher in faecal- compared with mucosal-associated microbiota in IBS patients (P < 0.005). No differences were found in healthy subjects. CONCLUSIONS: Differences in the mucosal-associated microbiota between healthy individuals and IBS patients are minimal (one bacterial group) compared to differences in the faecal microbiota of both groups (53 bacterial groups). Microbial aberrations characterising IBS are more pronounced in the faeces than in the mucosa.
BACKGROUND: The faecal-associated microbiota is commonly seen as a surrogate of the mucosal-associated microbiota. However, previous studies indicate that they are different. Furthermore, analyses of the mucosal microbiota are commonly done after standard bowel cleansing, affecting the microbial composition. AIM: To compare the mucosal-associated microbiota, obtained from unprepared colon, with faecal-associated microbiota in healthy subjects and irritable bowel syndrome (IBS) patients. METHODS: Faecal and mucosal biopsies were obtained from 33 IBSpatients and 16 healthy controls. Of IBSpatients, 49% belonged to the diarrhoea-predominant subgroup and 80% suffered from IBS symptoms during at least 5 years. Biopsies were collected from unprepared sigmoid colon and faecal samples a day before colonoscopy. Microbiota analyses were performed with a phylogenetic microarray and redundancy discriminant analysis. RESULTS: The composition of the mucosal- and the faecal-associated microbiota in unprepared sigmoid colon differs significantly (P = 0.002). Clinical characteristics of IBS did not correlate with this difference. Bacteroidetes dominate the mucosal-associated microbiota. Firmicutes, Actinobacteria and Proteobacteria dominate the faecal-associated microbiota. Healthy subjects had a significantly higher (P < 0.005) abundance (1.9%) of the bacterial group uncultured Clostridiales I in the mucosal-associated microbiota than IBSpatients (0.3%). Bacterial diversity was higher in faecal- compared with mucosal-associated microbiota in IBSpatients (P < 0.005). No differences were found in healthy subjects. CONCLUSIONS: Differences in the mucosal-associated microbiota between healthy individuals and IBSpatients are minimal (one bacterial group) compared to differences in the faecal microbiota of both groups (53 bacterial groups). Microbial aberrations characterising IBS are more pronounced in the faeces than in the mucosa.
Authors: Susana Fuentes; Noortje G Rossen; Mirjam J van der Spek; Jorn Ha Hartman; Laura Huuskonen; Katri Korpela; Jarkko Salojärvi; Steven Aalvink; Willem M de Vos; Geert R D'Haens; Erwin G Zoetendal; Cyriel Y Ponsioen Journal: ISME J Date: 2017-04-11 Impact factor: 10.302
Authors: Ann E Rogers; Yi-Juan Hu; Ye Yue; Emily F Wissel; Robert A Petit Iii; Simone Jarrett; Jennifer Christie; Timothy D Read Journal: PeerJ Date: 2021-05-11 Impact factor: 2.984