scholarly journals Molecular analysis of faecal and duodenal samples reveals significantly higher prevalence and numbers of Pseudomonas aeruginosa in irritable bowel syndrome

2011 ◽  
Vol 60 (2) ◽  
pp. 236-245 ◽  
Author(s):  
Angèle P. M. Kerckhoffs ◽  
Kaouther Ben-Amor ◽  
Melvin Samsom ◽  
Michel E. van der Rest ◽  
Joris de Vogel ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Irritable Bowel Syndrome ◽  
Small Intestine ◽  
Healthy Subjects ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Pcr Analysis ◽  
Rrna Gene ◽  
Faecal Samples ◽  
Small Intestinal ◽  
Irritable Bowel

Intestinal microbiota may play a role in the pathophysiology of irritable bowel syndrome (IBS). In this case–control study, mucosa-associated small intestinal and faecal microbiota of IBS patients and healthy subjects were analysed using molecular-based methods. Duodenal mucosal brush and faecal samples were collected from 37 IBS patients and 20 healthy subjects. The bacterial 16S rRNA gene was amplified and analysed using PCR denaturing gradient gel electrophoresis (DGGE). Pooled average DGGE profiles of all IBS patients and all healthy subjects from both sampling sites were generated and fingerprints of both groups were compared. The DGGE band fragments which were confined to one group were further characterized by sequence analysis. Quantitative real-time PCR (q-PCR) was used to quantify the disease-associated microbiota. Averaged DGGE profiles of both groups were identical for 78.2 % in the small intestinal samples and for 86.25 % in the faecal samples. Cloning and sequencing of the specific bands isolated from small intestinal and faecal DGGE patterns of IBS patients showed that 45.8 % of the clones belonged to the genus Pseudomonas, of which Pseudomonas aeruginosa was the predominant species. q-PCR analysis revealed higher levels (P<0.001) of P. aeruginosa in the small intestine of IBS patients (8.3 %±0.950) than in the small intestine of healthy subjects (0.1 %±0.069). P. aeruginosa was also significantly (P<0.001) more abundant (2.34 %±0.31) in faeces of IBS patients than in faeces of healthy subjects (0.003 %±0.0027). This study shows that P. aeruginosa is detected more frequently and at higher levels in IBS patients than in healthy subjects, suggesting its potential role in the pathophysiology of IBS.

scholarly journals Evaluation of Small Intestinal Motility in a Rat Model of Irritable Bowel Syndrome

2021 ◽  
Author(s):  
Masamichi Sato ◽  
Takahiro Kudo ◽  
Nobuyasu Arai ◽  
Reiko Kyodo ◽  
Kenji Hosoi ◽  
...  
Keyword(s):  
Irritable Bowel Syndrome ◽  
Small Intestine ◽  
Real Time ◽  
Rat Model ◽  
Intestinal Motility ◽  
Restraint Stress ◽  
Rat Models ◽  
Small Intestinal Motility ◽  
Small Intestinal ◽  
Irritable Bowel

Abstract Background: The correlation between small intestinal motility alteration and irritable bowel syndrome (IBS) is not well evaluated. Aims: To assess the small intestinal and colonic transits in an IBS rat model with restraint stress and determine the role of small intestinal motility in the IBS pathophysiology.Methods: Restraint stress was utilized to make adolescent IBS rat models that were evaluated for clinical symptoms, including stool frequency and diarrhea. The small intestinal motility and transit rate were also evaluated. The amounts of mRNA encoding corticotropin-releasing hormone, mast cell, and serotonin (5-Hydroxytryptamine; 5-HT) receptor 3a were quantified using real-time polymerase chain reaction (PCR); the 5-HT expression was evaluated using immunostaining.Results: Restraint stress significantly increased the number of fecal pellet outputs, stool water content, and small intestinal motility in the IBS rat models. There was no difference in real-time PCR results, but immunostaining analysis revealed that 5-HT expression in the small intestine was significantly increased in the IBS rat models.Conclusions: In the adolescent rat model of IBS with restraint stress, we observed an increase in small intestinal and colonic motility. In the small intestine, enhanced 5-HT secretion in the distal portion may be involved in increasing the small intestinal motility.

scholarly journals No distinct microbiome signature of irritable bowel syndrome found in a Swedish random population

Gut ◽  
2019 ◽  
Vol 69 (6) ◽  
pp. 1076-1084 ◽  
Author(s):  
Luisa W Hugerth ◽  
Anna Andreasson ◽  
Nicholas J Talley ◽  
Anna M Forsberg ◽  
Lars Kjellström ◽  
...  
Keyword(s):  
Irritable Bowel Syndrome ◽  
Gut Microbiome ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Self Rated Health ◽  
Faecal Samples ◽  
Rrna Gene Sequencing ◽  
Irritable Bowel ◽  
Taxonomic Groups ◽  
Faecal Microbiome

ObjectiveThe ethiopathogenesis of irritable bowel syndrome (IBS) is unknown. While a link to the gut microbiome is postulated, the heterogeneity of the healthy gut makes it difficult to draw definitive conclusions. We aimed to describe the faecal and mucosa-associated microbiome (MAM) and health correlates on a community cohort of healthy and IBS individuals with no colonoscopic findings.DesignThe PopCol study recruited a random sample of 3556 adults; 745 underwent colonoscopy. IBS was defined by Rome IV criteria and organic disease excluded. 16S rRNA gene sequencing was conducted on sigmoid biopsy samples from 376 representative individuals (63 IBS cases) and faecal samples from 185 individuals (32 IBS cases).ResultsWhile sigmoid MAM was dominated by Lachnospiraceae, faeces presented a higher relative abundance of Ruminococcaceae. Microbial richness in MAM was linearly correlated to that in faeces from the same individual (R²=0.255, p<3E-11) as was diversity (R²=0.06, p=0.0022). MAM diversity decreased with increasing body mass index (BMI; Pearson’s r=−0.1, p=0.08) and poorer self-rated health (r=−0.15, p=0.007), but no other health correlates. Faecal microbiome diversity was correlated to stool consistency (r=−0.16, p=0.043). Several taxonomic groups were correlated to age, BMI, depression and self-reported health, including Coprococcus catus associated with lower levels of depression (r=−0.003, p=0.00017). The degree of heterogeneity observed between IBS patients is higher than that observed between healthy individuals.ConclusionsNo distinct microbial signature was observed in IBS. Individuals presenting with low self-rated health or high BMI have lower gut microbiome richness.

scholarly journals A novel stepwise integrative analysis pipeline reveals distinct microbiota-host interactions and link to symptoms in irritable bowel syndrome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Annikka Polster ◽  
Lena Öhman ◽  
Julien Tap ◽  
Muriel Derrien ◽  
Boris Le Nevé ◽  
...  
Keyword(s):  
Irritable Bowel Syndrome ◽  
Complex Variable ◽  
16S Rrna Gene Sequencing ◽  
Integrative Analysis ◽  
Rrna Gene ◽  
Analysis Pipeline ◽  
Host Interactions ◽  
Functional Relationships ◽  
Irritable Bowel ◽  
Host Genes

AbstractAlthough incompletely understood, microbiota-host interactions are assumed to be altered in irritable bowel syndrome (IBS). We, therefore, aimed to develop a novel analysis pipeline tailored for the integrative analysis of microbiota-host interactions and association to symptoms and prove its utility in a pilot cohort. A multilayer stepwise integrative analysis pipeline was developed to visualize complex variable associations. Application of the pipeline was demonstrated on a dataset of IBS patients and healthy controls (HC), using the R software package to analyze colonic host mRNA and mucosal microbiota (16S rRNA gene sequencing), as well as gastrointestinal (GI) and psychological symptoms. In total, 42 IBS patients (57% female, mean age 33.6 (range 18–58)) and 20 HC (60% female, mean age 26.8 (range 23–41)) were included. Only in IBS patients, mRNA expression of Toll-like receptor 4 and genes associated with barrier function (PAR2, OCLN, TJP1) intercorrelated closely, suggesting potential functional relationships. This host genes-based “permeability cluster” was associated to mucosa-adjacent Chlamydiae and Lentisphaerae, and furthermore associated to satiety as well as to anxiety, depression and fatigue. In both IBS patients and HC, chromogranins, secretogranins and TLRs clustered together. In IBS patients, this host genes-based “immune-enteroendocrine cluster” was associated to specific members of Firmicutes, and to depression and fatigue, whereas in HC no significant association to microbiota was identified. We have developed a stepwise integrative analysis pipeline that allowed identification of unique host-microbiota intercorrelation patterns and association to symptoms in IBS patients. This analysis pipeline may aid in advancing the understanding of complex variable associations in health and disease.

scholarly journals On the Pathogenesis of the Irritable Bowel Syndrome: The Irritable Bowel or the Irritable Patient?

1990 ◽  
Vol 4 (1) ◽  
pp. 33-38
Author(s):  
Stephen M Collins
Keyword(s):  
Irritable Bowel Syndrome ◽  
Healthy Subjects ◽  
Behavioural Problem ◽  
Pain Tolerance ◽  
Organic Disease ◽  
Gastrointestinal Dysfunction ◽  
Traditional Philosophy ◽  
Irritable Bowel ◽  
Experience Pain

The traditional perspective of irritable bowel syndrome (IBS) as a behavioural problem has tended to downplay the role of gastrointestinal dysfunction. Contrary to predictions based on the traditional philosophy, a recent study has shown that IBS patients have increased pain tolerance compared to healthy subjects. This profile of pain tolerance is similar to that seen in chronic organic disease of the gut (eg, Crohn's disease), raising the possibility that IBS patients may experience pain resulting from gastrointestinal dysfunction. The recent finding of increased airway responsiveness to inhaled methacholine in certain IBS patients provides an objective and quantifiable measurement of tissue dysfunction in that syndrome, and focuses attention on possible mechanisms underlying the altered responsiveness of hollow organs in patients with IBS; these mechanisms are discussed.

scholarly journals Encapsulated cyclosporine does not change the composition of the human microbiota when assessed ex vivo and in vivo

2020 ◽  
Vol 69 (6) ◽  
pp. 854-863
Author(s):  
Catherine O'Reilly ◽  
Órla O’Sullivan ◽  
Paul D. Cotter ◽  
Paula M. O’Connor ◽  
Fergus Shanahan ◽  
...  
Keyword(s):  
Pilot Study ◽  
Gut Microbiota ◽  
Targeted Delivery ◽  
Healthy Subjects ◽  
Ex Vivo ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Microbiota Composition ◽  
Faecal Samples

Introduction. Management of steroid-refractory ulcerative colitis has predominantly involved treatment with systemic cyclosporine A (CyA) and infliximab. Aim. The purpose of this study was to assess the effect of using a colon-targeted delivery system CyA formulation on the composition and functionality of the gut microbiota. Methodology. Ex vivo faecal fermentations from six healthy control subjects were treated with coated minispheres (SmPill) with (+) or without (−) CyA and compared with a non-treated control in a model colon system. In addition, the in vivo effect of the SmPill+CyA formulation was investigated by analysing the gut microbiota in faecal samples collected before the administration of SmPill+CyA and after 7 consecutive days of administration from eight healthy subjects who participated in a pilot study. Results. Analysis of faecal samples by 16S rRNA gene sequencing indicated little variation in the diversity or relative abundance of the microbiota composition before or after treatment with SmPill minispheres with or without CyA ex vivo or with CyA in vivo. Short-chain fatty acid profiles were evaluated using gas chromatography, showing an increase in the concentration of n-butyrate (P=0.02) and acetate (P=0.32) in the faecal fermented samples incubated in the presence of SmPill minispheres with or without CyA. This indicated that increased acetate and butyrate production was attributed to a component of the coated minispheres rather than an effect of CyA on the microbiota. Butyrate and acetate levels also increased significantly (P=0.05 for both) in the faecal samples of healthy individuals following 7 days’ treatment with SmPill+CyA in the pilot study. Conclusion. SmPill minispheres with or without CyA at the clinically relevant doses tested here have negligible direct effects on the gut microbiota composition. Butyrate and acetate production increased, however, in the presence of the beads in an ex vivo model system as well as in vivo in healthy subjects. Importantly, this study also demonstrates the relevance and value of using ex vivo colon models to predict the in vivo impact of colon-targeted drugs directly on the gut microbiota.

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