Colitis Colon Research Articles

English

BACKGROUND Colonoscopy is considered as a diagnostic procedure of choice for patients presenting with chronic diarrhoea / bloody diarrhoea. Colonoscopic mucosal biopsies have shown to be accurate indicators of extent of the involvement of colon in inflammatory bowel disease. Also, colonoscopy is still considered as the gold standard in cancer surveillance. The present study was undertaken to find out the utility of colonoscopic biopsies in histomorphological spectrum of colorectal lesions. METHODS This was a three-year retrospective study carried out in the Department of Pathology, at MGM Medical College, Aurangabad. Patient’s clinical details, colonoscopic findings and apparent pathology were noted in 206 cases along with final histopathological diagnosis. Biopsies which showed significant findings were included in the study. RESULTS In the study, the male to female ratio was 2.4 : 1. Out of 206 colorectal biopsies, 146 (70.8 %) were non-neoplastic and 60 (29.2 %) were neoplastic lesions. Amongst non-neoplastic lesions, maximum cases were of chronic colitis with 4 cases of granulomatous colitis and 30 cases of inflammatory bowel disease. Adenocarcinoma was the most common histologic type in neoplastic lesions (66.6 %), with rectum being the most common site followed by colonic polyps (25 %). As far as age group was concerned, the 2nd decade was dominated by chronic colitis, 3rd decade by adenomatous polyps and 5th decade by adenocarcinoma. CONCLUSIONS Histomorphological profile of colorectal biopsies has a wide spectrum ranging from infectious diseases, inflammatory bowel disorders to colorectal malignancies. Histopathology with correlation of clinical and endoscopic findings plays a major role in accurate diagnosis of colorectal lesions. KEYWORDS Colonoscopy, Biopsies, Neoplastic, Non-Neoplastic, Colitis, Adenocarcinoma

Recommendations of the Spanish Working Group on Crohn’s disease and Ulcerative Colitis (Grupo Español de Trabajo en Enfermedad de Crohn y Colitis Ulcerosa — GETECCU) on dysplasia screening in inflammatory bowel disease patients

Colonic inflammatory bowel diseases have a higher risk of developing colorectal cancer compared to the general population, which is why they require endoscopic screening techniques with specific follow-up intervals based on the different risk factors described on the literature. This position paper analyzes the current scientific evidence for the different endoscopic techniques available today, how their implementation should be carried out in endoscopic units and describes in detail how their implementation should be carried out, in which patients and with what interval, and finally, what should be the response to finding dysplasia, proposing a specific follow-up algorithm.

Ramulus mori polysaccharide-loaded PLGA nanoparticles and their anti-inflammatory effects in vivo

In this study, ramulus mori polysaccharide (RMP) was encapsulated into Poly (lactic-co-glycolicacid) (PLGA) to form PLGA-RMP (PR). The aim of study is to investigate anti-inflammatory effects of PR. The particle size of PR nanoparticles was approximately 205.6 ± 1.86 nm. PR nanoparticles showed significant therapeutic effects on colitis mice model, evidenced by attenuation of the loss of body weight, reduction of the DAI score, and restoration of the colon length. From the histopathological analysis, alleviation of the histopathological damage, less production of IFN-γ and IL-6, and improvement of IL-10 were observed with the treatment of PR. Meanwhile, the treatment of PR not only promoted the expression of ZO-1 and occludin, but also improved the contents of acetate, propionate, and butyrate in the colitis colon. Furthermore, PR extenuated the reduction of the diversity and richness of gut microbiota induced by DSS, and decreased the ratio of Firmicutes to Bacteroidetes while increasing the proportion of Clostridium XIVa, Mucispirillum, and Paraprevotella in the gut microbiota. What's more, PR nanoparticles attenuated the metabolic disorders in the colitis colon induced by DSS. These results indicated that PR nanoparticles could serve as a potent nanomedicine to treat IBD and be used as potential prebiotics.

CGAS restricts colon cancer development by protecting intestinal barrier integrity

The DNA-sensing enzyme cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) regulates inflammation and immune defense against pathogens and malignant cells. Although cGAS has been shown to exert antitumor effects in several mouse models harboring transplanted tumor cell lines, its role in tumors arising from endogenous tissues remains unknown. Here, we show that deletion of cGAS in mice exacerbated chemical-induced colitis and colitis-associated colon cancer (CAC). Interestingly, mice lacking cGAS were more susceptible to CAC than those lacking stimulator of interferon genes (STING) or type I interferon receptor under the same conditions. cGAS but not STING is highly expressed in intestinal stem cells. cGAS deficiency led to intestinal stem cell loss and compromised intestinal barrier integrity upon dextran sodium sulfate-induced acute injury. Loss of cGAS exacerbated inflammation, led to activation of STAT3, and accelerated proliferation of intestinal epithelial cells during CAC development. Mice lacking cGAS also accumulated myeloid-derived suppressive cells within the tumor, displayed enhanced Th17 differentiation, but reduced interleukin (IL)-10 production. These results indicate that cGAS plays an important role in controlling CAC development by defending the integrity of the intestinal mucosa.

P606 Adherence to endoscopic surveillance guidelines for advanced lesions and colorectal cancer in Inflammatory Bowel Disease in Spain: a collaborative study of AEG and GETECCU

Abstract Background Patients with colon Inflammatory Bowel Disease (IBD) have a higher risk of colorectal cancer (CRC) than general population. Current guidelines establish endoscopic surveillance recommendations; however, epidemiological studies show poor compliance. The main aim of our study was to analyse adherence to endoscopic surveillance guidelines. Secondary aim was to evaluate the prevalence and time-to advanced lesions or CRC. Methods Retrospective multicentre study of patients with IBD followed-up in the participating centres between 2005 and 2020, who were diagnosed of IBD between 2005 and 2008, with criteria for CRC surveillance. Patients with CRC before IBD diagnosis were excluded. The ECCO 2013–2017 guidelines were used to evaluate adherence. Adenomatous lesions with >25% of villous component, >1cm or with high-grade dysplasia or serrated lesions >1cm or with any degree of dysplasia were considered advanced lesions. Software used for all analysis was R in its 3.6.1 version. Normality was checked with the Shapiro-Wilks test. Mean comparison was carried out using t-Student test while normality assumptions held true, otherwise, Mann-Whitney test. Time-to advanced lesions or CRC event between patients that had adherence to ECCO guidelines versus those who did not was performed through Kaplan-Meier and Log-rank test. P-values below 0.05 were considered significant. Results A total of 1004 (713 Ulcerative Colitis, 252 Crohn’s disease and 39 Indeterminate Colitis; 52% male) patients from 25 centres were recruited with a median age of 36 (26–47) years. 87% of all patients were included in the endoscopic surveillance programme. The main reasons for non-inclusion were the absence of indication by the physician (38%) and the presence of inflammatory activity (37%). Adherence to the first or subsequent surveillance colonoscopies was 45% and 61%, respectively, with a total adherence rate of 32%. Prevalence of advanced lesions or CRC was 4% and 7 cases of CRC were detected. Time-to-detection of these lesions since IBD diagnosis was significantly longer in non-adherent patients (13.4 + 1.3 vs13.04 + 1.7; p<0.001). Adherence was associated to a higher detection of advanced lesions or CRC compared to non-adherent patients (HR: 1.97; IC: 1.02–3.79; p=0.043) (Figure 1). Conclusion Adherence to ECCO guidelines for endoscopic surveillance is low in this Southern European population. A higher and earlier detection of advanced lesions or CRC was identified in the adherent group. The results of this study highlight the need to improve compliance with the recommendations to obtain better outcomes.

P041 CDKN2B-AS1 (ANRIL) expression is decreased in Inflammatory Bowel Disease epithelia and in Celiac, and its reduction is linked with induced cells proliferation

Abstract Background Long non-coding RNAs (lncRNAs) have attenuated expression in several immune-mediated disorders. Using mRNAseq of intestinal biopsies, we identified a widespread dysregulation of 459 lncRNAs in the ileum of treatment-naïve pediatric Crohn Disease (CD) patients. We noted that large fraction of downregulated lncRNAs were correlated with epithelial functions. CDKN2B-AS1 (ANRIL) is one of the top most down-regulated lncRNA in CD, and showed decreased expression in Ulcerative Colitis (UC) colon tissues in recent studies. Methods Transcriptomics data is used to evaluate CDKN2B-AS1 expression in mucosal biopsies datasets and in gut epithelia. siRNA oligonucleotides targeting most CDKN2B-AS1 transcripts using Lipofectamine RNAiMAX is used to modulate CDKN2B-AS1 function, and RT-PCR to evaluate mRNA expression. xCELLigence system with gold microelectrodes in plate base is used to measure the impedance as an indicator for cell index. Results CDKN2B-AS1 is down-regulated in bulk mucosal biopsies obtained from CD ileum [fold change (FC) -8, corrected p=1.6E-5], in UC rectum (FC -9.4, corrected p=3.9E-18), and in celiac duodenum (FC -2.3, corrected p=0.03) in comparison to controls. CDKN2B-AS1 is detected under basal conditions in HT-29 cells. Two sets of CDKN2B-AS1 siRNA oligonucleotides (targeting most transcripts) achieved up to 60% reduction in CDKN2B-AS1 expression in HT-29 cells (p=1E-04) as confirmed by RT-PCR using two sets of primers. CDKN2B-AS1 reduction significantly increased cell index as measured by xCELLigence (doubled the index, p=1.7E-03). mRNAseq of the CDKN2B-AS1 reduced HT-29, showed reduction of the tumor suppressor gene APC in CDKN2B-AS1 siRNA treated cells (FC=-1.75, p=0.04) and of TGFBR2 (FC=-1.75, p=0.04). In contrast, reduction of CDKN2B-AS1 resulted in increase in WNT11 (FC=2.1, p=0.02) and TGFB1 (FC=1.9, p=0.04), and induction of the replication associated topoisomerase TOP1MT (FC=2.7, p=0.001). We confirmed these mRNAseq results using RT-PCR. Finally, mimicking inflammation by treating HT-29 with IL1β and LPS, reduced CDKN2B-AS1 expression (by 70%, p=6.3E-04) and doubled the cell index (p=1.8E-03). Conclusion We detected reduced CDKN2B-AS1 expression in three inflammatory disease affecting the gut in different location along the GI tract. Using HT-29 model system we were able to show, as was previously shown, an increase in cell index in CDKN2B-AS1 siRNA treated cells. We supplement those showing effect on down-stream genes that may be relevant in controlling cell proliferation. We further show that upon inflammatory triggering of HT-29 cells, CDKN2B-AS1 expression is reduced and cell index is increased, which may suggest a potential role in epithelial renewal in inflammation.

Virtual chromoendoscopy with iSCAN as an alternative method to dye-spray chromoendoscopy for dysplasia detection in long-standing colonic inflammatory bowel disease: a case–control study

Objective Patients with long-standing colonic inflammatory bowel disease (cIBD) are at increased risk of developing colorectal cancer (CRC). Dye-spray chromoendoscopy (DCE) with targeted biopsies is the preferred technique for surveillance of dysplasia. Virtual chromoendoscopy (VCE) are arising to improve detection rates and adherence to surveillance guidelines, although its role is not yet well defined. The purpose of this study is to assess the effectiveness of VCE with iSCAN as an alternative method for dysplasia detection in cIBD. Methods Retrospective case–control study with 191 patients included, 98 in the DCE (Indigo carmine) group and 93 in the VCE (iSCAN, twin-mode 1–3) group. The dysplasia detection and the exploration time were analysed. A logistic regression analysis was performed to ascertain the factors related to colonic dysplasia. Results A total of 44 dysplastic lesions were detected in 21 (11%) patients. No differences were found in the per lesion and the per patient analysis (dysplastic versus non-dysplastic). Median withdrawal time was shorter in the VCE group than in the DCE group (9 min versus 14 min; p < .001). Location of lesions in the right colon was independently associated with an increased risk for colonic dysplasia (OR = 4.04, 95%CI 1.11–14.65; p = .034) after adjusting for age at inclusion, age at diagnosis, high risk for CRC and Kudo pit pattern. Conclusions VCE with iSCAN presents a similar diagnostic performance to conventional DCE in the detection of colonic dysplasia in patients with long-standing cIBD. Furthermore, VCE with iSCAN is a less time-consuming surveillance alternative to DCE.

Potential Mechanisms Mediating the Protective Effects of Tricholoma matsutake-Derived Peptides in Mitigating DSS-Induced Colitis.

Intestinal barrier dysfunction and inflammatory cytokine secretion play crucial roles in inflammatory bowel disease (IBD). Herein, we investigated the protective effects of Tricholoma matsutake-derived peptides SDIKHFPF and SDLKHFPF against dextran sulfate sodium-induced colitis. Both peptides alleviated colitis signs, including diarrhea, weight loss, bloody stools, colon shortening, and histopathological changes, while reducing mucus destruction, goblet cell exhaustion, and intestinal permeability. SDIKHFPF and SDLKHFPF protected the barrier function by promoting the expression of tight junction (TJ) zonula occludens-1 and occludin within the colon, as well as attenuating colonic inflammation through myeloperoxidase and pro-inflammatory cytokine suppression. Western blotting indicated that the peptides suppressed myosin light chain kinase (MLCK) and nuclear factor kappa B (NF-κB) levels, inhibiting MLC phosphorylation. SDLKHFPF was more potent than SDIKHFPF. These findings suggest that peptide SDLKHFPF mitigates colitis by regulating TJ protein expression and pro-inflammatory cytokine production via NF-κB/MLCK/p-MLC signaling, improving the barrier function.

DNA Methylation Change Profiling of Colorectal Disease: Screening towards Clinical Use.

Colon cancer remains one of the leading causes of cancer-related deaths worldwide. Transformation of colon epithelial cells into invasive adenocarcinomas has been well known to be due to the accumulation of multiple genetic and epigenetic changes. In the past decade, the etiology of inflammatory bowel disease (IBD) which is characterized by chronic inflammation of the intestinal mucosa, was only partially explained by genetic studies providing susceptibility loci, but recently epigenetic studies have provided critical evidences affecting IBD pathogenesis. Over the past decade, A deep understanding of epigenetics along with technological advances have led to identifying numerous genes that are regulated by promoter DNA hypermethylation in colorectal diseases. Recent advances in our understanding of the role of DNA methylation in colorectal diseases could improve a multitude of powerful DNA methylation-based biomarkers, particularly for use as diagnosis, prognosis, and prediction for therapeutic approaches. This review focuses on the emerging potential for translational research of epigenetic alterations into clinical utility as molecular biomarkers. Moreover, this review discusses recent progress regarding the identification of unknown hypermethylated genes in colon cancers and IBD, as well as their possible role in clinical practice, which will have important clinical significance, particularly in the era of the personalized medicine.

Berberine-Loaded Carboxylmethyl Chitosan Nanoparticles Ameliorate DSS-Induced Colitis and Remodel Gut Microbiota in Mice.

Inflammatory bowel disease (IBD) is a refractory disorder characterized by chronic and recurrent inflammation. The progression and pathogenesis of IBD is closely related to oxidative stress and irregularly high concentrations of reactive oxygen species (ROS). A new oxidation-responsive nano prodrug was constructed from a phenylboronic esters-modified carboxylmethyl chitosan (OC-B) conjugated with berberine (BBR) that degrades selectively in response to ROS. The optimized micelles exhibited well-controlled physiochemical properties and stability in a physiological environment. OC-B-BBR micelles could effectively encapsulate the anti-inflammatory drug berberine and exhibit ideal H2O2-triggered release behavior as confirmed by in vitro drug loading and release studies. The in vivo anti-inflammatory effect and regulation of gut microbiota caused by it were explored in mice with colitis induced by dextran sodium sulfate (DSS). The results showed that OC-B-BBR significantly ameliorated colitis symptoms and colon damage by regulating the expression levels of IL-6 and remodeling gut microbiota. In summary, this study exhibited a novel BBR-loaded Carboxylmethyl Chitosan nano delivery system which may represent a promising approach for improving IBD treatment.

An immuno-blocking agent targeting IL-1β and IL-17A reduces the lesion of DSS-induced ulcerative colitis in mice.

In recent decades when biological agents have flourished, a part of patients suffering from inflammatory bowel disease (IBD) have received the treatment of tumor necrosis factor inhibitors or IL-1 antibodies. This study aims to investigate the anti-colitis effects of bispecific antibody (FL-BsAb1/17) targeting IL-1β and IL-17A comparing with TNF-α soluble receptor medicine etanercept. IBD model in mice was established by drinking 3% DSS (dextran sulfate sodium salt). On the first day of drinking DSS, treatments with etanercept (5 mg/kg) or different doses of FL-BsAb1/17 (1 mg/kg, 5 mg/kg, and 10 mg/kg) were started by intraperitoneal injection every other day. The results demonstrated that FL-BsAb1/17 treatment was more effective than etanercept at the same dose (5 mg/kg) in relieving the typical symptom of ulcerative colitis induced by DSS (such as the severity score and intestinal shortening), and down-regulating the expression of inflammatory factors (IL-17A, IL-6, IL-12, IL-22, IL-1β, IL-23, TNF-α) in the serum and colon. FL-BsAb1/17 could also reduce the degree of intestinal fibrosis. The same dose of FL-BsAb1/17 (5 mg/kg) performed better than etanercept in down-regulating MDA and up-regulating SOD (superoxide dismutase), CAT (catalase), and T-AOC (total antioxidant capacity) in serum. Both FL-BsAb1/17 and etanercept could reduce the transcription of Bax and increase the transcription of Bcl-2 and slow down apoptosis in colitis colon tissue. We conclude that the blocking of IL-1β and IL-17A can inhibit DSS-induced ulcerative colitis and FL-BsAb1/17 may have potential to become a new dual-target candidate for colitis treatment.

The Western Dietary Pattern Combined with Vancomycin-Mediated Changes to the Gut Microbiome Exacerbates Colitis Severity and Colon Tumorigenesis.

Previous work by our group using a mouse model of inflammation-associated colorectal cancer (CAC) showed that the total Western diet (TWD) promoted colon tumor development. Others have also shown that vancomycin-mediated changes to the gut microbiome increased colorectal cancer (CRC). Therefore, the objective of this study was to determine the impact of vancomycin on colon tumorigenesis in the context of a standard mouse diet or the TWD. A 2 × 2 factorial design was used, in which C57Bl/6J mice were fed either the standard AIN93G diet or TWD and with vancomycin in the drinking water or not. While both the TWD and vancomycin treatments independently increased parameters associated with gut inflammation and tumorigenesis compared to AIN93G and plain water controls, mice fed the TWD and treated with vancomycin had significantly increased tumor multiplicity and burden relative to all other treatments. Vancomycin treatment significantly decreased alpha diversity and changed the abundance of several taxa at the phylum, family, and genus levels. Conversely, basal diet had relatively minor effects on the gut microbiome composition. These results support our previous research that the TWD promotes colon tumorigenesis and suggest that vancomycin-induced changes to the gut microbiome are associated with higher tumor rates.

Linking bacterial enterotoxins and alpha defensin 5 expansion in the Crohn's colitis: A new insight into the etiopathogenetic and differentiation triggers driving colonic inflammatory bowel disease.

Evidence link bacterial enterotoxins to apparent crypt-cell like cells (CCLCs), and Alpha Defensin 5 (DEFA5) expansion in the colonic mucosa of Crohn’s colitis disease (CC) patients. These areas of ectopic ileal metaplasia, positive for Paneth cell (PC) markers are consistent with diagnosis of CC. Retrospectively, we: 1. Identified 21 patients with indeterminate colitis (IC) between 2000–2007 and were reevaluation their final clinical diagnosis in 2014 after a followed-up for mean 8.7±3.7 (range, 4–14) years. Their initial biopsies were analyzed by DEFA5 bioassay. 2. Differentiated ulcer-associated cell lineage (UACL) analysis by immunohistochemistry (IHC) of the CC patients, stained for Mucin 6 (MUC6) and DEFA5. 3. Treated human immortalized colonic epithelial cells (NCM460) and colonoids with pure DEFA5 on the secretion of signatures after 24hr. The control colonoids were not treated. 4. Treated colonoids with/without enterotoxins for 14 days and the spent medium were collected and determined by quantitative expression of DEFA5, CCLCs and other biologic signatures. The experiments were repeated twice. Three statistical methods were used: (i) Univariate analysis; (ii) LASSO; and (iii) Elastic net. DEFA5 bioassay discriminated CC and ulcerative colitis (UC) in a cohort of IC patients with accuracy. A fit logistic model with group CC and UC as the outcome and the DEFA5 as independent variable differentiator with a positive predictive value of 96 percent. IHC staining of CC for MUC6 and DEFA5 stained in different locations indicating that DEFA5 is not co-expressed in UACL and is therefore NOT the genesis of CC, rather a secretagogue for specific signature(s) that underlie the distinct crypt pathobiology of CC. Notably, we observed expansion of signatures after DEFA5 treatment on NCM460 and colonoids cells expressed at different times, intervals, and intensity. These factors are key stem cell niche regulators leading to DEFA5 secreting CCLCs differentiation ‘the colonic ectopy ileal metaplasia formation’ conspicuously of pathogenic importance in CC.

Therapeutic and Prebiotic Effects of Five Different Native Starches on Dextran Sulfate Sodium-Induced Mice Model of Colonic Colitis.

The availability of studies related to the effects of natural macronutrients on inflammatory bowel disease (IBD) remain relatively limited. This study investigates whether and to what extent the consumption of five different native starches alleviate the clinical symptoms and dysbiosis of gut microbiota associated with colitis. Using dextran sodium sulfate (DSS)-induced mouse model of colitis, the potential effects of native potato starch (PS), pea starch (PEAS), corn starch (CS), Chinese yam starch (CYS), and red sorghum starch (RSS) on the clinical manifestations and dysbiosis of gut microbiota are studied. Compared to CS and RSS, the consumption of PEAS, PS, and CYS significantly diminishes clinical enteritis symptoms, including reduced disease activity index, and the alleviated degree of colonic histological damage. Furthermore, the analysis of gut microbiota reveals the significant prebiotic characteristics of PEAS, PS and CYS, as indicated by the maintenance of gut microbiota hemostasis and the inhibition of typically pathogenic bacteria, including Escherichia coli and Helicobacter hepaticus. Starches from potato, pea, and Chinese yam alleviate colitis symptoms in a mouse model, and also show significant prebiotic characteristics. These findings suggest a cost-effective and convenient dietary strategy for the management of IBD.

Dietary Taxifolin Protects Against Dextran Sulfate Sodium-Induced Colitis via NF-κB Signaling, Enhancing Intestinal Barrier and Modulating Gut Microbiota.

Taxifolin is a natural antioxidant polyphenol with various bioactivities and has many beneficial effects on human gut health. However, little is known of its function on colitis. In this study, the protective effects of taxifolin on colitis symptoms, inflammation, signaling pathways, and colon microbiota were investigated using dextran sulfate sodium (DSS)-induced colitis mice. Intriguingly, pre-administration of taxifolin alleviated the colitis symptoms and histological changes of the DSS-challenged mice. Supplementation of taxifolin significantly inhibited the secretions of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 and significantly increased the secretions of IL-10, secretory immunoglobulin A, superoxide dismutase, and immunoglobulins (IgA, IgG, and IgM) in DSS-induced colitis mice. In addition, the activation of nuclear factor kappa B (NF-κB; p65 and IκBα) signaling was significantly suppressed by taxifolin supplementation. The expression of tight junction proteins (claudin-1 and occludin) was significantly increased by taxifolin. Moreover, 16S rDNA sequencing revealed that the DSS-induced changes of colon microbiota composition and microbial functions (amino acid metabolism and MAPK signaling) were restored by taxifolin, including the decreases of the abundances of Bacteroides, Clostridium ramosum, Clostridium saccharogumia, Sphingobacterium multivorum, and the ratio of Bacteroidetes/Firmicutes, and the increases of the abundances of Desulfovibrio C21 c20 and Gemmiger formicilis at species level. In conclusion, these results revealed that dietary taxifolin has a great potential to prevent colitis by inhibiting the NF-κB signaling pathway, enhancing intestinal barrier, and modulating gut microbiota.

Macrophage-derived EDA-A2 inhibits intestinal stem cells by targeting miR-494/EDA2R/\u03b2-catenin signaling in mice

The mucosa microenvironment is critical for intestinal stem cell self-renewal and reconstruction of the epithelial barrier in inflammatory bowel disease (IBD), where the mechanisms underlying cross-talk between intestinal crypts and the microenvironment remain unclear. Here, we firstly identified miR-494-3p as an important protector in colitis. miR-494-3p levels were decreased and negatively correlated with the severity in human IBD samples, as well as in colitis mice. In colitis crypts, a notable cytokine–cytokine receptor, miR-494-3p-targeted EDA2R and the ligand EDA-A2, suppressed colonic stemness and epithelial repair by inhibiting β-catenin/c-Myc. In differentiated IECs, miR-494-3p inhibits macrophage recruitment, M1 activation and EDA-A2 secretion by targeting IKKβ/NF-κB in colitis. A miR-494-3p agomir system notably ameliorated the severity of colonic colitis in vivo. Collectively, our findings uncover a miR-494-3p-mediated cross-talk mechanism by which macrophage-induced intestinal stem cell impairment aggravates intestinal inflammation.

Accurate Classification of Pediatric Colonic Inflammatory Bowel Disease Subtype Using a Random Forest Machine Learning Classifier.

The pediatric inflammatory bowel disease (PIBD) classes algorithm was developed to bring consistency to labelling of colonic IBD, but labels are exclusively based on features atypical for ulcerative colitis (UC). The aim of the study was to develop an algorithm and identify features that discriminate between pediatric UC and colonic Crohn disease (CD). Baseline clinical, endoscopic, radiologic, and histologic data, including the PIBD class features in 74 colonic IBD (56: UC, 18: colonic CD) patients were collected. The PIBD class features and additional features common to UC were used to perform initial clustering, using similarity network fusion (SNF). We trained a Random Forest (RF) classifier on the full dataset and used a leave-one-out approach to evaluate model accuracy. The top-features were used to build a new classifier, which we tested on 15 previously unused patients. We then performed clustering with SNF on the top RF features and assessed ability to discriminate between UC and colonic-CD independent of a supervised model. The initial SNF clustering with 58 patients demonstrated 2 groups: group 1 (n = 39, 90% UC) and group 2 (n = 19, 68% colonic-CD). Our RF classifier correctly labelled 97% of the 58 patients based on leave-one-out cross validation and identified the 7 most important features (3 histological and 4 endoscopic) to clinically distinguish these groups. We trained a new RF classifier with the top 7 features and found 100% accuracy in a set of 15 held-out patients. Finally, post hoc clustering with these 7 features revealed 2 groups of patients: group 1 (n = 55, 98% UC) and group 2 (n = 18, 94% colonic-CD). A combination of supervised and unsupervised analyses identified a short list of features, which consistently distinguish UC from colonic CD. Future directions include validation in other populations.

Urinary 8-iso PGF2α and 2,3-dinor-8-iso PGF2α can be indexes of colitis-associated colorectal cancer in mice

Early diagnosis of colorectal cancer is needed to reduce the mortal consequence by cancer. Lipid mediators play critical role in progression of colitis and colitis-associated colon cancer (CAC) and some of their metabolites are excreted in urine. Here, we attempted to find novel biomarkers in urinary lipid metabolite of a murine model of CAC. Mice were received single administration of azoxymethane (AOM) and repeated administration of dextran sulfate sodium (DSS). Lipid metabolites in their urine was measured by liquid chromatography mass spectrometry and their colon was collected to perform morphological study. AOM and DSS caused inflammation and tumor formation in mouse colon. Liquid chromatography mass spectrometry-based comprehensive analysis of lipid metabolites showed that cyclooxygenase-mediated arachidonic acid (AA) metabolites, prostaglandins, and reactive oxygen species (ROS)-mediated AA metabolites, isoprostanes, were predominantly increased in the urine of tumor-bearing mice. Among that, urinary prostaglandin (PG)E2 metabolite tetranor-PGEM and PGD2 metabolite tetranor-PGDM were significantly increased in both of urine collected at the acute phase of colitis and the carcinogenesis phase. On the other hand, two F2 isoprostanes (F2-IsoPs), 8-iso PGF2α and 2,3-dinor-8-iso PGF2α, were significantly increased only in the carcinogenesis phase. Morphological study showed that infiltrated monocytes into tumor mass strongly expressed ROS generator NADPH (p22phox). These observations suggest that urinary 8-iso PGF2α and 2,3-dinor-8-iso PGF2α can be indexes of CAC.

Is diversion free ileal pouch-anal anastomosis a safe procedure? A meta-analysis of 4973 cases.

Ileal pouch-anal anastomosis (IPAA) has been established as the procedure of choice for patients who require excision of the colon and rectum for familial adenomatous polyposis and ulcerative colitis. The requirement for proximal stomal diversion in IPAA is controversial. To compare post-operative outcomes following IPAA with and without proximal diversion. Computerised literature search, of Ovid MEDLINE and EMBASE. Full-text comparative studies published between 1992 and 2019, in English language and on adult patients. Ileal pouch-anal anastomosis with or without proximal stomal diversion following proctocolectomy. Outcome measures were anastomotic leak, anastomosis strictures, re-operations, pouch failure, intra-abdominal sepsis, small bowel obstruction/ileus and mortality. Five hundred and forty-six studies were screened. Fourteen relevant studies included 4973 cases (1832 patients with no stomas vs 3141 with stomas). Anastomotic strictures (p≤0.0001 OR 0.40; 95% CI (0.26-0.62)) and pouch failures (p = 0.003 OR 0.54; 95% CI (0.36-0.82)) were higher in diverted than non-diverted patients. Re-operation was more frequently required in non-diverted patients (p= 0.02 OR 2.51; 95% CI (1.12-5.59)). Heterogeneity was low in 5 out of 7 variables. In selected patients, diversion-free IPAA is a safe procedure associated with lower anastomotic stricture and pouch failure rates than diverted IPAA. This appears to occur at the expense of a higher re-operation rate. An RCT is required to help define the selection criteria.

Mouse Models of Colitis-Associated Colon Cancer.

Crohn's disease (CD) and ulcerative colitis are two main clinically defined forms of chronic inflammatory bowel disease (IBD). Chronic intestinal inflammation is inextricably linked to colitis-associated colon carcinogenesis (CAC). Patients with ulcerative colitis (UC) and Crohn's disease (CD) have an increased risk of colon cancer. Our understanding of IBD and IBD-associated colon carcinogenesis depends largely on rodent models. AOM-DSS-induced colitis-associated colon cancer in mice is the most widely used and accepted model that can recapitulate the human IBD-associated colon cancer. Here, we have provided detailed protocols of this mouse model of experimentally induced chronic intestinal inflammation-associated colon cancer. We will also discuss the protocols for the isolation and analysis of inflammatory immune cells from the colon.