Colonic biogeography in health and ulcerative colitis.
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ABSTRACT:
SUBMITTER: Lavelle A
PROVIDER: S-EPMC5154370 | biostudies-other | 2016 Sep
REPOSITORIES: biostudies-other
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Project description:BackgroundRecent studies have found gut microbiota to be closely associated with onset and perpetuation of UC. Currently, studies about gut microbiota have mainly covered samples collected from the intestinal lumen. However, the luminal flora is only part of the gut microbiota. Studies of the changes in mucosal flora under pathological conditions have been lacking. In this study, we investigated the correlation between the onset of UC and flora changes in different intestinal layers.MethodsThe dextran sulfate sodium(DSS)-induced UC model was established by exposing mice to cycles of DSS. The luminal contents, an inner mucus layer, and outer mucus layer were harvested under sterile conditions. The samples were then analyzed using high-throughput sequencing of 16S rRNA V3 + V4 amplicons. The colonic microbiota composition and diversity were analyzed and compared using MetaStat, LefSe, multivariate analysis of variance, and spatial statistics.ResultsThe DSS-induced UC mouse model was successfully established. The diversity of the microbiota from luminal content, the outer mucus layer, and inner mucus layer were significantly different in both control and UC model groups. The statistically different OTUs belonged to Lachnospiraceae and Ruminococcaceae families within the order Clostridiales were mainly localized to the outer mucus layer.ConclusionsThe alterations in flora composition and diversity mainly occurred in the colonic outer mucus layer. The change of flora in the colonic mucus layers is of great significance in the understanding of common features of gut flora in IBD and the understanding of the relationship between gut flora and disease progression.
| S-EPMC6332670 | biostudies-literature
Project description:The samples are a part of a study aiming at diagnosing ulcerative colitis from genome-wide gene expression analysis of the colonic mucosa. Colonic mucosal samples were collected as endoscopic pinch biopsies from ulcerative colitis patients and from control subjects. Samples with and without macroscopic signs of inflammation were collected from the patients. Experiment Overall Design: The series contain eight UC samples with macroscopic signs of inflammation, 13 UC smaples without macroscopic signs of inflammation, five control subjects.
2008-06-20 | E-GEOD-9452 | biostudies-arrayexpress
Project description:Akkermansia muciniphila utilises colonic mucin as its substrate. Abundance is reduced in ulcerative colitis (UC), as is the relative proportion of sulphated mucin in the mucus gel layer (MGL). It is unknown if these phenomena are related, however reduced sulphated mucins could contribute to reduced abundance, owing to a lack of substrate. The aim of this study was to quantify A. muciniphila within the MGL and to relate these findings with markers of inflammation and the relative proportion of sulphomucin present. Colonic biopsies and mucus brushings were obtained from 20 patients with active UC (AC), 14 with quiescent UC (QUC) and 20 healthy controls (HC). A. muciniphila abundance was determined by RT-PCR. High iron diamine alcian-blue staining was performed for histological analysis. Patients with AC had reduced abundance of A. muciniphila compared to HC and QUC. A positive association was found between A. muciniphila abundance and higher percentage of sulphated mucin (ρ 0.546, p = 0.000). Lower abundances of A. muciniphila correlated with higher inflammatory scores (ρ = 0.294 (p = 0.001)). This study confirms an inverse relationship between A. muciniphila and inflammation and a positive association between A. muciniphila abundance and percentage of sulfated mucin in the MGL.
| S-EPMC6821857 | biostudies-literature
Project description:BACKGROUND:Ulcerative colitis (UC) is one of the major types of inflammatory bowel diseases and is associated with a significantly increased risk of not only lymphoproliferative disorders but also lymphomas, of which most cases are related to the long-term usage of immunosuppressants. Here, we demonstrate a very rare case of other iatrogenic immunodeficiency-associated colonic diffuse large B-cell lymphoma (Oii-DLBCL) complicating UC and rectal perforation. In addition, we reviewed the clinicopathological features of previous cases of DLBCL related to UC. CASE PRESENTATION:A 68-year-old man was diagnosed with left-sided UC 26?months prior. Although he was followed by immunosuppressive therapy with azathioprine and infliximab, an emergency total proctocolectomy was performed due to rectal perforation. The resected specimen exhibited irregular wall thickening and elevated multinodular lesions extending from the mid-transverse colon to the rectum, measuring up to 52?cm in length. Histologically, the lesion was diagnosed as Oii-DLBCL and crypt abscess surrounded by mixed inflammatory cell was remained. CONCLUSION:Oii-DLBCL complicating UC with rectal perforation is extremely rare. Macro- and microscopic findings are important for early diagnosis of the lesion.
| S-EPMC7137478 | biostudies-literature
Project description:Background and aimsPatients with ulcerative colitis [UC] with long disease duration have a higher risk of developing colitis-associated cancer [CAC] compared with patients with short-duration UC. The aim of this study was to identify transcriptomic differences associated with the duration of UC disease.MethodsWe conducted transcriptome profiling on 32 colonic biopsies [11 long-duration UC, ≥20 years; and 21 short-duration UC, ≤5 years] using Affymetrix Human Transcriptome Array 2.0. Differentially expressed genes [fold change > 1.5, p < 0.05] and alternative splicing events [splicing index > 1.5, p < 0.05] were determined using the Transcriptome Analysis Console. KOBAS 3.0 and DAVID 6.8 were used for KEGG and GO analysis. Selected genes from microarray analysis were validated using qPCR.ResultsThere were 640 differentially expressed genes between both groups. The top ten upregulated genes were HMGCS2, UGT2A3 isoforms, B4GALNT2, MEP1B, GUCA2B, ADH1C, OTOP2, SLC9A3, and LYPD8; the top ten downregulated genes were PI3, DUOX2, VNN1, SLC6A14, GREM1, MMP1, CXCL1, TNIP3, TFF1, and LCN2. Among the 123 altered KEGG pathways, the most significant were metabolic pathways; fatty acid degradation; valine, leucine, and isoleucine degradation; the peroxisome proliferator-activated receptor signalling pathway; and bile secretion, which were previously linked with CAC. Analysis showed that 3560 genes exhibited differential alternative splicing between long- and short-duration UC. Among them, 374 were differentially expressed, underscoring the intrinsic relationship between altered gene expression and alternative splicing.ConclusionsLong-duration UC patients have altered gene expressions, pathways, and alternative splicing events as compared with short-duration UC patients, and these could be further validated to improve our understanding of the pathogenesis of CAC.
| S-EPMC6535502 | biostudies-literature
Project description:OBJECTIVES:A healed intestinal mucosa is the aim of therapy in acute ulcerative colitis (UC). Disruption of mucosal wound healing may lead to severe complications including intestinal fibrosis. This study examined mucosal gene expression in the healing process of acute UC with a special focus on known mediators of fibrosis. METHODS:Endoscopic biopsies from patients with acute, moderate to severe UC were analyzed with a quantitative polymerase chain reaction array for 84 genes involved in fibrosis pathways. All patients were treated with infliximab (anti- tumor necrosis factor). Biopsies were taken before therapy and when disease remission was reached, defined as a Mayo score of ≤2, with an endoscopic subscore of 0 or 1. A healthy control group was included. Immunostaining of matrix metallopeptidase 9 and smooth muscle actin was performed. RESULTS:Mucosal biopsies from acute UC (n = 28), remission UC (n = 28), and healthy controls (n = 13) were analyzed. Fibrosis and extracellular matrix-associated genes were upregulated in the endoscopically healed UC mucosa vs controls, with collagen type III alpha 1 chain, actin alpha 2, lysyl oxidase, TIMP metallopeptidase inhibitor 3, and caveolin 1 uniquely showing no overlap with acute disease. Pro- and antifibrotic mediators (interleukin [IL]13 receptor subunit alpha 2, IL1B, IL10, tumor necrosis factor, snail family transcriptional repressor 1, and C-C motif chemokine ligand 2) were upregulated in both acute and healed UC compared with controls. An attenuated pattern of the canonical transforming growth factor beta (TGFB) pathway was observed in acute UC and to a lesser extent in the healed mucosa, except for TGFB2, which was enhanced. DISCUSSION:The endoscopically healed mucosa of UC showed a persisting dysregulation of fibrosis-associated mediators compared with controls, including extracellular matrix remodeling, profibrotic cytokines, and TGFB signaling pathways.
| S-EPMC6884345 | biostudies-literature
Project description:BackgroundWe aimed to identify the risk factors associated with colonic cytomegalovirus (CMV) infection in ulcerative colitis (UC) and to compare the clinical course between antiviral therapy-treated and -untreated groups in mucosal CMV-polymerase chain reaction (PCR) -positive cases.MethodsWe retrospectively selected 46 UC patients (>15 years old) in active phase who underwent colonoscopy with biopsy and were analyzed for CMV infection by mucosal PCR between October 2011 and December 2015 at our institution. Colonic CMV in inflamed mucosa was detected using quantitative real-time PCR. The clinical course was evaluated, including need for drug therapy/surgery or drug therapy intensification. In addition, we evaluated the clinical course between CMV-DNA- cases and CMV-DNA+ cases with low viral load.ResultsAt baseline, CMV-DNA+ patients were significantly older, had higher endoscopic scores, and required higher corticosteroid doses during the past 4 weeks than CMV-DNA- patients (p< 0.05). No significant differences were observed in disease duration, disease distribution, laboratory data, or use of other medication between CMV-DNA+ and CMV-DNA- patients. In the anti-CMV-treated group with a median (range) DNA load of 16,000 (9,000-36,400), 3patients achieved remission without additional UC therapy, 2 required additional UC therapy, and 1 required colectomy despite azathioprine and infliximab therapy. In the CMV-untreated group with a median (range) DNA load of 919 (157-5,480), all patients achieved remission with UC therapy alone. No significant difference was observed in the clinical course between CMV-DNA- cases and CMV-DNA+ cases with low viral loads.ConclusionsAging, endoscopic UC activity, and corticosteroid dose predispose to colonic CMV infection, as determined by mucosal PCR, in UC. UC treatment without anti-CMV therapy may be warranted, particularly in patients with low-load CMV-DNA. Anti-CMV therapy alone does not always achieve clinical response in UC even in cases with high-load PCR.
| S-EPMC5590814 | biostudies-literature
Project description:BackgroundStool DNA testing in patients with inflammatory bowel disease (IBD) may detect colorectal cancer and advanced precancers with high sensitivity; less is known about the presence of DNA markers in small IBD lesions, their association with metachronous neoplasia, or contribution to stool test positivity.MethodsAt a single center in 2 blinded phases, we assayed methylated bone morphogenic protein 3, methylated N-Myc downstream-regulated gene 4, and mutant KRAS in DNA extracted from paraffin-embedded benign lesions, and matched control tissues of patients with IBD, who were followed for subsequent colorectal dysplasia. Stool samples from independent cases and controls with lesions <1 cm or advanced neoplasms were assayed for the same markers.ResultsAmong IBD lesions (29 low-grade dysplasia, 19 serrated epithelial change, and 10 sessile serrated adenoma/polyps), the prevalence of methylation was significantly higher than in mucosae from 44 matched IBD controls (P < 0.0001 for methylated bone morphogenic protein 3 or methylated N-Myc downstream-regulated gene 4). KRAS mutations were more abundant in serrated epithelial change than all other groups (P < 0.001). Subsequent dysplasia was not associated with DNA marker levels. In stools, the sensitivity of methylated bone morphogenic protein 3 as a single marker was 60% for all lesions <1 cm, 63% for low-grade dysplasia ≥1 cm and 81% for high-grade dysplasia/colorectal cancer, all at 91% specificity (P < 0.0001).ConclusionsSelected DNA markers known to be present in advanced IBD neoplasia can also be detected in both tissues and stools from IBD patients with small adenomas and serrated lesions. Mutant KRAS exfoliated from serrated epithelial change lesions might raise false-positive rates. These findings have relevance to potential future applications of stool DNA testing for IBD surveillance.
| S-EPMC4911339 | biostudies-literature
Project description:BackgroundChronic ulcerative colitis (CUC) and colonic Crohn's disease (CD) increase colorectal neoplasia (CRN) risk. While sessile serrated polyp (SSP) is a known cancer precursor, serrated epithelial changes (SEC) are of uncertain prevalence and neoplastic risk.AimTo assess the serrated lesion detection rates in CUC and CD and documented incidence of subsequent CRN in a retrospective, single-centre cohort study.MethodsPatients were identified by a central diagnostic index and pathology review confirmed SEC, SSP, CUC and CD diagnoses from 2006-12. Matched controls were identified from among all CUC and CD patients having colonoscopy during the second half of the time period. All were followed for incident CRN, estimated by the Kaplan-Meier method.ResultsBetween 2006 and 2012, 79 SEC and 10 SSP cases were identified. Detection rates were estimated to be 10/1000 and 2/1000 patients, for SEC and SSP respectively, among 4208 unique CUC or CD patients having colonoscopy from 2010-12. With only 10 cases, SSP patients were not further analysed. Cumulative incidence of subsequent CRN at 1 and 3 years was 12% (95% CI, 0-30%) and 30% (3-57%), respectively, in SEC patients compared to 4% (0-12%) and 9% (0-23%), respectively, in CUC or CD controls (P = 0.047, log-rank). However, this statistical difference was not significant after patients were stratified for history of prior or synchronous dysplasia (P = 0.09).ConclusionsSerrated epithelial changes and sessile serrated polyps are uncommonly detected by colonoscopy in chronic ulcerative colitis and Crohn's disease patients. Histology with changes of serrated epithelium may be associated with risk of subsequent colorectal neoplasia, however further studies are needed to explore this relationship.
| S-EPMC4894660 | biostudies-literature
Project description:To investigate the miRNA expression in colonic mucosal biopsies from endoscopically inflamed and non inflamed regions of ulcerative colitis (UC) patients.Colonic mucosal pinch biopsies were analyzed from the inflamed and non inflamed regions of same UC patient. Total RNA was isolated and differential miRNA profiling was done using microarray platform. Quantitative Real Time PCR was performed in colonic biopsies from inflamed (n = 8) and non-inflamed (n = 8) regions of UC and controls (n = 8) to validate the differential expression of miRNA. Potential targets of dysregulated miRNA were identified by using in silico prediction tools and probable role of these miRNA in inflammatory pathways were predicted.The miRNA profile of inflamed colonic mucosa differs significantly from the non-inflamed. Real time PCR analysis showed that some of the miRNA were differentially expressed in the inflamed mucosa as compared to non inflamed mucosa and controls (miR-125b, miR-223, miR-138, and miR-155), while (miR-200a) did not show any significant changes. In contrast to microarray, where miR-378d showed downregulation in the inflamed mucosa, qRT-PCR showed a significant upregulation in the inflamed mucosa as compared to the non inflamed. The in silico prediction analysis revealed that the genes targeted by these miRNAs play role in the major signaling pathways like MAPK pathway, NF-κB signaling pathway, cell adhesion molecules which are all assciated with UC.The present study reports disease specific alteration in the expression of miR-125b, miR-155, miR-223 and miR-138 in UC patients and also predict their biological significance.
| S-EPMC5550781 | biostudies-other