Ulcerative Colitis Colon Research Articles

Agmatine attenuates the severity of immunometabolic disorders by suppressing macrophage polarization: an in vivo study using an ulcerative colitis mouse model

Agmatine, an endogenous polyamine generated by the gut microbiota, positively affects host lifespan by regulating mononuclear cell or macrophage function. Although the regulatory pathways governing monocyte/macrophage differentiation have been well studied, the influence of the microbiome and its metabolites on monocyte/macrophage function have not been fully elucidated. To address this, we aimed to investigate the mechanisms whereby agmatine inhibits immunometabolic disorders using the colon of ulcerative colitis (UC) model mice. Agmatine (10 mM) attenuated pathological damage to colonic tissue and significantly improved the survival rate of UC model mice. In particular, treatment of UC model mice with 0.4, 2, and 10 mM agmatine resulted in mortality rates of 70 %, 20 %, 10 %, and 0 %, respectively. In a macrophage-depletion model, agmatine regulated the inflammatory microenvironment by affecting macrophages: it reduced the proportion of M1 macrophages and increased that of M2 macrophages in UC model mice. In cultured macrophages, agmatine inhibited lipopolysaccharide-induced inflammatory cytokine and NO secretion, as detected by enzyme-linked immunosorbent assay and the Griess assay, respectively. Agmatine partially reduced inflammatory factor production by inhibiting histone deacetylase, as detected by fluorometric assay. These findings provide evidence that agmatine efficiently suppresses macrophage polarization in UC mice, highlighting its potential as an anti-inflammatory agent against UC.

The intestinal mucin isoform landscape reveals region-specific biomarker panels for inflammatory bowel disease patient stratification.

Mucosal healing is considered as a key therapeutic endpoint in inflammatory bowel diseases (IBD) and comprises endoscopic improvement of inflammation without taking barrier healing into account. Mucins are critical components of the mucosal barrier function that give rise to structurally diverse isoforms. Unraveling disease-associated mucin isoforms that could act as an indication for barrier function would greatly enhance IBD management. We present the intestinal mucin RNA isoform landscape in IBD and control patients using a targeted mucin isoform sequencing approach on a discovery cohort (n = 106). Random Forest modeling (n = 1683 samples) with external validation (n = 130 samples) identified unique mucin RNA isoform panels that accurately stratified IBD patients in multiple subpopulations based on inflammation, IBD subtype (Crohn's disease (CD), ulcerative colitis (UC)), and anatomical location of the intestinal tract (i.e. ileum, proximal colon, distal colon, rectum). Particularly, the mucin RNA isoform panels obtained from the inflamed UC and CD distal colon showed high performance in distinguishing inflamed biopsies from their control counterparts (AUC of 93.3% and 91.1% in the training, 95.0% and 96.0% in the test, and 89.5% and 78.3% in the external validation datasets, respectively). Furthermore, the differentially expressed MUC4 (PB.1238.363), MUC5AC (PB.2811.15), MUC16 (ENST00000397910.8) and MUC1 (ENST00000462317.5, ENST00000620103.4) RNA isoforms frequently occurred throughout the different panels highlighting their role in IBD pathogenesis. We unveiled region-specific mucin RNA isoform panels capturing the heterogeneity of the IBD patient population and showing great potential to indicate barrier function in IBD patients.

Identifying polyamine related biomarkers in diagnosis and treatment of ulcerative colitis by integrating bulk and single-cell sequencing data

Ulcerative colitis (UC) is a chronic inflammatory disorder of the colon, and its pathogenesis remains unclear. Polyamine metabolic enzymes play a crucial role in UC. In this study, we aimed to identify pivotal polyamine-related genes (PRGs) and explore the underlying mechanism between PRGs and the disease status and therapeutic response of UC. We analyzed mRNA-sequencing data and clinical information of UC patients from the GEO database and identified NNMT, PTGS2, TRIM22, TGM2, and PPARG as key PRGs associated with active UC using differential expression analysis and weighted gene co-expression network analysis (WCGNA). Receiver operator characteristic curve (ROC) analysis confirmed the accuracy of these key genes in UC and colitis-associated colon cancer (CAC) diagnosis, and we validated their relationship with therapeutic response in external verification sets. Additionally, single-cell analysis revealed that the key PRGs were specific to certain immune cell types, emphasizing the vital role of intestinal tissue stem cells in active UC. The results were validated in vitro and in vivo experiments, including the colitis mice model and CAC mice model. In conclusion, these key PRGs effectively predict the progression of UC patients and could serve as new pharmacological biomarkers for the therapeutic response of UC.

Interferon γ Expressing Mucosal Cells in Pediatric Chronic Inflammatory Bowel Disease.

The pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC) is multifactorial and includes aberrations in the composition of gastrointestinal mucosal inflammatory cells. Accurate identification of CD and UC is important as treatment and prognosis differs; however, CD and UC may be difficult to differentiate. Interferon γ (IFNγ) expression appears to be increased in ileal mucosa from CD patients, implying that IFNγ could be a diagnostically useful marker to differentiate CD from UC. This study uses automated assessment of IFNγ immunohistochemical expression in archival GI mucosal biopsies from stomach, duodenum, terminal ileum, and colon in a pediatric population to address this possibility. IFNγ positive mucosal cells are increased in the colon in both CD and UC compared to normal colon and in the ileum of CD compared to normal and UC. The abundance of IFNγ positive cells is not correlated with the presence of active inflammation, indicating that active inflammation is not responsible for the variance in abundance of IFNγ positive cells between cohorts and sites. Overlap between CD, UC, and normal suggests that IFNγ immunohistochemistry may only be clinically useful in select situations such as undetermined inflammatory bowel disease and additional study in these areas is warranted.

Clinical and diagnostic value of transrectal ultrasound in assessing the severity of ulcerative colitis

Background. Endoscopic and histological studies play a decisive role in the diagnosis of inflammatory bowel diseases, as they allow confirming the diagnosis, determining the degree of inflammatory activity, the extent of intestinal damage, and monitoring the course of disease and the effectiveness of therapy. Howe­ver, it is not possible to assess the state of all intestinal layers with colonoscopy. Modern non-invasive methods such as ultrasound, computed tomography, and magnetic resonance imaging cope best with this purpose. With their help, you can assess the state of the intestinal wall and obtain a cross-sectional image of the intestine, evaluate extraintestinal structures (lymph nodes, vessels, fatty tissue). It can be said that endoscopy and ultrasound search for the same type of information but look at different things. Deepening the knowledge about the role of ultrasound of the distal parts of the colon in ulcerative colitis (UC) will contribute to the improvement of diagnosis, development of methods for determining the activity of UC, control of therapy, which will allow optimizing the choice of adequate treatment measures. The goal of the work: to improve the diagnosis of ulcerative colitis based on the study of ultrasonographic parameters of the rectum. Materials and methods. Transrectal ultrasound was performed on an expert-class SonoScape S60 ultrasound scanner using a low-frequency convex probe of 3.5 MHz and a rectovaginal convex probe of 6 MHz. Transperineal and transrectal approaches were used. Results. Wall thickness and submucosal thickness differed significantly in moderate and severe UC. Analysis of transrectal ultrasound indicators depending on the endoscopic activity of the UC revealed no significant differences in the rectal wall thickness. But there was a tendency to increase in the thickness of the mucous layer and the coefficient of deformation with increasing endoscopic activity. Most patients had an increase in the degree of blood flow density, which depended on the disease severity. During the regression analysis, a relationship was found between the intestinal wall thickness (r = 0.44; p = 0.0121) and submucosal layer thickness (r = 0.86; p = 0.006) with the Mayo index. A correlation was revealed between the thickness of the colon wall and the frequency of bowel movements (r = 0.37; p = 0.018), leukocytosis (r = 0.38; p = 0.016) and erythrocyte sedimentation rate (r = 0.35; p = 0.027). The blood flow density in the intestinal wall positively correlated with the presence of edema (r = 0.32; р = 0.045), the severity of the vascular pattern (r = 0.42; р = 0.008), the presence of erosions (r = 0.4; р = 0.011) and bleeding of the mucous membrane (r = 0.50; p = 0.001). The coefficient of deformation positively correlated with the presence of flatulence (r = 0.35; р = 0.048). Conclusions. Endoscopic exa­mination in patients with UC should be supplemented with transrectal ultrasound. A correlation was found between the intestinal wall thickness and the thickness of the submucosal layer in patients with UC and the Mayo index. A tendency to increase in the thickness of the mucous layer and the coefficient of deformation with increasing endoscopic activity was determined. Relationships between endoscopic and ultrasound parameters can be used to assess disease activity.

P172 Spatial Transcriptomics Characterization of S1P Pathway Genes in Ulcerative Colitis and Crohn’s Disease Colon Tissues

Abstract Background Inflammatory bowel diseases (IBD), such as ulcerative colitis (UC) and Crohn’s disease (CD) are chronic inflammatory diseases of the gastrointestinal tract, related to the confluence of environmental and immunological factors in genetically predisposed individuals. Activated T and B cells migrate from the lymphoid tissue into the circulation through the interaction of Sphingosine-1-phosphate (S1P) and the S1P1 receptor (S1P1), which can perpetuate inflammation and lead to tissue damage. Targeting of cellular migratory pathways has emerged as a novel therapeutic paradigm in IBD. The aim of this study is to characterize the S1P pathway-related genes and signaling pathways driving the pathogenesis of UC and CD. Methods Spatial transcriptomics analysis was performed in health volunteer (HV, n=2), UC (n=4) and CD (n=2) FFPE colon tissues using the GeoMX platform and NanoString whole transcriptome atlas (WTA) assay. The WTA panel was run on 8 samples stained with antibodies to S1P1, pan Cytokeratin, and CD45. Six regions of interests (ROIs) were selected in each sample based on the staining and each ROI were split into two areas (CD45+ or CD45-). Differential gene expression and enriched pathways analysis including S1P pathway genes were performed in CD45+ and CD45- segments in HV, UC and CD colon tissues. Results A total of 6085 and 6054 differentially expressed genes were identified from the CD45+ segments in UC and CD respectively, compared to HV colon (P=0.05), including the genes that are involved in T cell activation (e.g., HLA-DPA1, CCDC13), immune cell migration (e.g., ADAM15, CCL5) and tissue damage (e.g., FABP6, PDK4). Interestingly, significant differences were identified in UC and CD in S1P pathway gene expression. Specifically, SMPD1, a gene involved in generating ceramide and regulating inflammatory responses, was the most significantly up-regulated gene from both CD45+ and CD45- compartments in UC compared to HV colon. While CERS2 and CERS6, genes related to S1P metabolism, were significantly down-regulated genes in CD45+ and CD45- compartment in UC respectively, as compared to HV colon. Additionally, RTN4 (participates in the intestinal epithelial barrier function) and PLPP3 (dephosphorylates extracellular S1P to sphingosine) were most significantly down-regulated genes from CD45+ segments in both UC and CD compared to HV colon. Conclusion In summary, our study successfully validated the GeoMx transcriptome analysis approach in FFPE colon tissue and assessed the S1P pathway gene signature difference in HV, UC and CD colon tissues supporting the pathway’s role in IBD. Results could also facilitate the identification of potential S1P pathway UC and CD disease biomarkers.

P052 Mucosal IgG-like naive B-cell expansion and maturation contribute to ulcerative colitis pathogenesis

Abstract Background A higher abundance of colonic naive B-cells and IgG plasma cells is implicated in the pathogenesis of ulcerative colitis (UC) during active inflammatory episodes. However, B-cell inhibition by targeting CD20 was found to be ineffective in achieving remission in UC patients indicating that the causal role of the B-cell expansion in UC is not well understood. In this study, we performed single cell RNA-sequencing (scRNA-seq) on mucosal tissue where we interrogated the B-cells in inflamed and non-inflamed UC colon biopsies. We subsequently explored the pathogenic role of B-cells in colitis mouse models. Methods We collected biopsies from the colon of 5 UC patients with active inflammation and 5 UC patients showing no inflamed mucosa. Three mucosal biopsies were collected from the same colon location for each patient and processed for scRNA-seq. We acquired usable transcriptomes of 21.475 cells. In a T-cell transfer colitis mice model, we evaluated the effects of the co-transfer of naive B-cells. Both CD4+ T and naive B-cells were transferred into SCID mice through intraperitoneal injection in ratios of 2:1, 1:1 and 1:2 (T:B ratio). The colitis course was followed for 35 days. Results Differential abundance analysis relative to all immune cells confirmed a higher abundance of naive B-cells (p= 0.03) and IgG plasma B-cells (p= 0.002) in inflamed relative to non-inflamed UC patient tissue, whereas no differences in abundance of transitional B-cells and memory B-cells were found. Pseudo-time analysis indicated a higher rate of maturation in the naive B-cells in inflamed tissue. This was evidenced by higher expression of IGHG1 (p= 0.025) and IGHG3 (p< 0.001) in naive B-cells in inflamed tissue. In a T-cell transfer model, we co-transferred naive B-cells to the CD4+ T-cell pool into SCID mice in various ratios (2:1, 1:1 and 1:2 T to B-cells respectively) and T-cell only control. Significant increase in disease severity was observed in a 1:2 T:B ratio based on body weight loss, increase of colon density, mouse colitis histology index and histological changes by disrupted mucosa. This observation was associated to significant elevated IgG concentration in serum and colon and B-cell presence in colon through immunohistochemistry. Conclusion We observed significantly higher abundance of naive B-cells and IgG plasma cells in inflamed relative to non-inflamed UC colon tissue, where naive B-cells were shown to be more mature and IgG-like in inflamed condition. Notably, transferring increased ratio of naive B-cells resulted in elevated disease severity in a colitis model, demonstrating its pathogenic role. Our findings suggest that specific targeting of the IgG-like naive B-cell may be beneficial for UC patients.

Increased ACE2 and TMPRSS2 expression in ulcerative colitis

Ulcerative colitis (UC) is a cryptogenic inflammatory bowel disease, and there is an urgent need to elucidate its pathogenesis. ACE2 and TMPRSS2, the entry molecules of SARS-CoV-2, are reportedly associated with the disease; however, no consensus has been reached yet. In this study, we examined the expression of ACE2 and TMPRSS2 in colon and rectal specimens of UC. We collected colorectal specimens from 60 patients (30 patients with UC and 30 controls from 2018 to 2021) and analyzed the proportion and intensity of ACE2 and TMPRSS2 using immunohistochemistry. The results revealed a significant increase in the proportion of ACE2 expression and the intensity of TMPRSS2 expression in patients with UC. ACE2 and TMPRSS2 expression in UC remained unaffected by the COVID-19 pandemic. We demonstrated that ACE2 and TMPRSS2 are likely involved in the pathogenesis of UC.

Precision therapy for ulcerative colitis: insights from mitochondrial dysfunction interacting with the immune microenvironment.

Accumulating evidence reveals mitochondrial dysfunction exacerbates intestinal barrier dysfunction and inflammation. Despite the growing knowledge of mitochondrial dysfunction and ulcerative colitis (UC), the mechanism of mitochondrial dysfunction in UC remains to be fully explored. We integrated 1137 UC colon mucosal samples from 12 multicenter cohorts worldwide to create a normalized compendium. Differentially expressed mitochondria-related genes (DE-MiRGs) in individuals with UC were identified using the "Limma" R package. Unsupervised consensus clustering was utilized to determine the intrinsic subtypes of UC driven by DE-MiRGs. Weighted gene co-expression network analysis was employed to investigate module genes related to UC. Four machine learning algorithms were utilized for screening DE-MiRGs in UC and construct MiRGs diagnostic models. The models were developed utilizing the over-sampled training cohort, followed by validation in both the internal test cohort and the external validation cohort. Immune cell infiltration was assessed using the Xcell and CIBERSORT algorithms, while potential biological mechanisms were explored through GSVA and GSEA algorithms. Hub genes were selected using the PPI network. The study identified 108 DE-MiRGs in the colonic mucosa of patients with UC compared to healthy controls, showing significant enrichment in pathways associated with mitochondrial metabolism and inflammation. The MiRGs diagnostic models for UC were constructed based on 17 signature genes identified through various machine learning algorithms, demonstrated excellent predictive capabilities. Utilizing the identified DE-MiRGs from the normalized compendium, 941 patients with UC were stratified into three subtypes characterized by distinct cellular and molecular profiles. Specifically, the metabolic subtype demonstrated enrichment in epithelial cells, the immune-inflamed subtype displayed high enrichment in antigen-presenting cells and pathways related to pro-inflammatory activation, and the transitional subtype exhibited moderate activation across all signaling pathways. Importantly, the immune-inflamed subtype exhibited a stronger correlation with superior response to four biologics: infliximab, ustekinumab, vedolizumab, and golimumab compared to the metabolic subtype. This analysis unveils the interplay between mitochondrial dysfunction and the immune microenvironment in UC, thereby offering novel perspectives on the potential pathogenesis of UC and precision treatment of UC patients, and identifying new therapeutic targets.

Proteomic Differences in Colonic Epithelial Cells in Ulcerative Colitis Have an Epigenetic Basis

The colonic epithelium serves as both a barrier to lumenal contents and a gatekeeper of inflammatory responses. In ulcerative colitis (UC), epithelial dysfunction is a core feature, but little is known about the cellular changes that may underlie disease pathology. We therefore evaluated how the chromatin epigenetics and proteome of epithelial cells differs between health and UC. We sorted live CD326+ epithelial cells from colon biopsies of healthy control (HC) screening colonoscopy recipients and from inflamed or uninflamed colon segments of UC patients on no biologic nor immunomodulator therapy (n= 5-7 subjects per group). Cell lysates were analyzed by proteomic evaluation and nuclei were analyzed for open chromatin with assay for transposase-accessible chromatin using sequencing. Proteins most highly elevated in inflamed UC biopsies relative to HC were those encoded by the HLA-DRA (P= 3.1× 10-33) and CD74 (P= 1.6× 10-27), genes associated with antigen presentation, and the antimicrobial dual oxidase 2 (DUOX2) (P= 3.2× 10-28) and lipocalin-2 (P= 2.2× 10-26) genes. Conversely, the water channel aquaporin 8 was strikingly less common with inflammation (P= 1.9× 10-18). Assay for transposase-accessible chromatin using sequencing revealed more open chromatin around the aquaporin 8 gene in HCs (P= 2.0× 10-2) and more around the DUOX2/DUOXA2 locus in inflamed UC colon (P= 5.7× 10-4), suggesting an epigenetic basis for differential protein expression by epithelial cells in health and disease. Numerous differences exist between the proteome and chromatin of colonic epithelial cells in UC patients and HCs, some of which correlate to suggest specific epigenetic mechanisms regulating the epithelial proteome.

Xianglian Zhixie Tablet Antagonizes Dextran Sulfate Sodium-Induced Ulcerative Colitis by Attenuating Systemic Inflammation and Modulating Gut Microbiota.

Xianglian Zhixie Tablet (XLZXT), a classical traditional Chinese medicine formulation, is commonly used to treat Ulcerative Colitis (UC) in China. However, the therapeutic mechanisms of XLZXT for UC have yet to be fully understood. This study aimed to investigate the curative benefits of XLZXT and its associated mechanisms for healing UC in mice. In the present study, the 1% dextran sulfate sodium (DSS) solution was used to establish the UC model in C57BL/6N mice. To investigate the therapeutic effects of XLZXT on DSS-induced UC mice, several parameters were measured, including DAI score, colon length, spleen index, pathological changes in colon tissue, and levels of inflammatory factors in plasma and colon tissue. By investigating the gut microbiota, assessing the levels of intestinal mucosal protein expression, and looking at the proteins involved in the TLR4/MyD88/NF-B p65 signaling pathway, the mechanisms of XLZXT impact on UC were investigated. Mouse feces were examined for patterns of gut microbiota expression using high-throughput sequencing of 16S rRNA. XLZXT effectively alleviated UC symptoms and colon pathological damage in DSS-induced UC mice. It improved body weight loss, stool consistency, and hematochezia, while also repairing colon damage. Moreover, it down-regulated pro-inflammatory cytokines (such as TNF-α, IL-1β, and IL-6), and up-regulated anti-inflammatory cytokines (such as IL-10). XLZXT also increased the expression of MUC-2, Occludin and ZO-1, while decreasing the expression of NF-κB, MyD88 and TLR4. Additionally, it regulated gut microbiota disorder by increasing the abundance of beneficial bacteria and reducing the adhesion of intestinal harmful bacteria. XLZXT demonstrated therapeutic effects on DSS-induced UC mice. The mechanisms may be associated with repairing the intestinal mucosal barrier, regulating the TLR4/MyD88/NF-κB p65 signaling pathway, and restoring the balance of gut microbiota.

Biomarkers of ulcerative colitis disease activity CXCL1, CYP2R1, LPCAT1, and NEU4 and their relationship to immune infiltrates

The diagnosis and assessment of ulcerative colitis (UC) poses significant challenges, which may result in inadequate treatment and a poor prognosis for patients. This study aims to identify potential activity biomarkers for UC and investigate the role of infiltrating immune cells in the disease. To perform gene set enrichment analysis, we utilized the cluster profiler and ggplot2 packages. Kyoto encyclopedia of genes and genomes was used to analyze degenerate enrichment genes. Significant gene set enrichment was determined using the cluster profiler and ggplot2 packages. Additionally, quantitative PCR (qRT-PCR) was employed to validate the expression of each marker in the ulcerative colitis model. We identified 651 differentially expressed genes (DEGs) and further investigated potential UC activity biomarkers. Our analysis revealed that CXCL1 (AUC = 0.710), CYP2R1 (AUC = 0.863), LPCAT1 (AUC = 0.783), and NEU4 (AUC = 0.833) were promising activity markers for the diagnosis of UC. Using rat DSS model, we validated these markers through qRT-PCR, which showed statistically significant differences between UC and normal colon mucosa. Infiltrating immune cell analysis indicated that M1 macrophages, M2 macrophages, activated dendritic cells (DCs), and neutrophils played crucial roles in the occurrence and progression of UC. Moreover, the activity markers exhibited varying degrees of correlation with activated memory CD4 T cells, M0 macrophages, T follicular helper cells, memory B cells, and activated DCs. The potential diagnostic genes for UC activity, such as CXCL1, CYP2R1, LPCAT1, and NEU4, as well as the infiltration of immune cells, may contribute to the pathogenesis and progression of UC.

Matrix metalloproteinases are key targets of acupuncture in the treatment of ulcerative colitis.

The aim of this study was to elucidate the key targets of acupuncture in the colon of ulcerative colitis (UC) mice model using full-length transcriptome sequencing. 2.5% dextran sodium sulfate (DSS)-induced colitis mice were treated with or without acupuncture. Intestinal pathology was observed, and full transcriptome sequencing and bioinformatic analysis were performed. The results demonstrated that acupuncture treatment reduced the UC symptoms, disease activity index score, and histological colitis score and increased body weight, colon length, and the number of intestinal goblet cells. In addition, acupuncture can also decrease the expression of necrotic biomarker phosphorylates mixed lineage kinase domain-like pseudo kinase (p-MLKL). Full-length transcriptome analysis indicated that acupuncture reversed the expression of 987 of the 1918 upregulated differentially expressed genes (DEGs), and 632 of the 1351 downregulated DEGs induced by DSS. DEGs regulated by acupuncture were mainly involved in inflammatory responses and intestinal barrier pathways. The protein-protein interaction network analysis revealed that matrix metalloproteinases (MMPs) are important genes regulated by acupuncture. Gene set enrichment analysis revealed that extracellular matrix (ECM)-receptor interaction was an important target of acupuncture. In addition, alternative splicing analysis suggested that acupuncture improved signaling pathways related to intestinal permeability, the biological processes of xenobiotics, sulfur compounds, and that monocarboxylic acids are closely associated with MMPs. Overall, our transcriptome analysis results indicate that acupuncture improves intestinal barrier function in UC through negative regulation of MMPs expression.

Costs of Healthcare for Children with Inflammatory Bowel Diseases (IBD) in Poland.

The last two decades have seen an increase in the incidence of inflammatory bowel disease (IBD) in many regions of the world, which has had a significant impact on both the social and economic burden of governments and healthcare systems. The aim of this study was to determine the level of hospitalization and outpatient treatment costs for children and adolescents with Crohn's disease and ulcerative colitis, depending on age, location, and activity of the disease. Methods were a retrospective analysis of the medical documentation of 240 children with IBD, hospitalized in the Gastroenterology Ward, Department of Pediatrics Medical University of Silesia (Katowice, Poland), along the three years follow up. The costs of treatment consisted of calculations of the supply of oral and intravenous drugs, calculations of the costs of laboratory tests, imaging, and consultations, as well as person-day costs. The most important results, determined with high costs of IBD treatment, are associated with younger age, high disease activity, localization in the small intestine in Crohn's disease (CD), and inflammatory changes in the entire colon in Ulcerative Colitis (UC). During the observation, it was noticed that the shortening of the hospitalization time did not significantly affect the total costs, which remained at a stable level.

The Role of hsa-miR-125b-5p Interaction with S1P/Ceramide Axis in the Potential Development of Inflammation-Associated Colon Cancer in Primary Sclerosing Cholangitis.

Primary sclerosing cholangitis (PSC) is characterised by the co-occurrence of inflammatory bowel diseases, particularly ulcerative colitis (UC). We investigated how the interaction of miR-125b with the sphingosine-1-phosphate (S1P)/ceramide axis may predispose patients with PSC, PSC/UC, and UC to carcinogenesis in the ascending and sigmoid colons. The overexpression of miR-125b was accompanied by the upregulation of S1P, ceramide synthases, ceramide kinases, and the downregulation of AT-rich interaction domain 2 in the ascending colon of PSC/UC, which contributed to the progression of high microsatellite instability (MSI-H) colorectal carcinoma. We also showed that the overexpression of sphingosine kinase 2 (SPHK2) and the genes involved in the glycolytic pathway in the sigmoid colon of UC led to the upregulation of Interleukin 17 (IL-17). In vitro stimulation of human intestinal epithelial cells (Caco-2, HT-29, and NCM460D) with lipopolysaccharide suppressed miR-125b and increased proinflammatory cytokines, whereas the induction of miR-125b activity by either a miR-125b mimetic or lithocholic acid resulted in the inhibition of miR-125b targets. In summary, miR-125b overexpression was associated with an imbalance in the S1P/ceramide axis that can lead to MSI-H cancer progression in PSC/UC. Furthermore, SPHK2 overexpression and a change in the cellular metabolic flux are important players in inflammation-associated colon cancer in UC.

Oral iron supplementation exacerbates dextran sulfate sodium (DSS)-induced colitis in mice

Background: Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) characterized by diarrhea, abdominal pain, and bloody, mucous-laden stools. In one-third of UC patients, severity of blood loss is sufficient to cause iron deficiency anemia, making it the most common extra-intestinal manifestation of UC. Oral iron supplementation is the first line treatment for IDA. However, there is a debate concerning the safety of orally administered iron, as some studies have reported an exacerbation of disease, whereas others report the treatment is well tolerated and effective. Aim: The purpose of this study was to determine the effect of oral iron administration on disease activity in dextran sulfate sodium (DSS)-induced colitis in mice, a model that effectively recapitulates ulcerative colitis. Hypothesis: We hypothesize that iron-supplemented chow will increase disease activity and lead to pathogenic changes in mice with DSS-induced colitis. Methods: Experimental acute colitis (UC) was produced in BALBc/AnNCrl (male and female; 7 weeks old) mice by administration of 3% DSS dissolved in drinking water for 7 days. Control mice received standard water. Normal control (NC) and UC (UC) animals were fed standard chow contained 200 parts per million (ppm) ferrous sulfate (2018 Teklad Global 18% Protein Rodent Diet, Huntingdon, UK), while normal (NCFe) and UC (UCFe) experimental animals were fed an iron-supplemented diet containing 600 ppm ferrous sulfate (2018 Teklad Global 18% Protein Rodent Custom Diet, Huntingdon, UK). Food and water were provided ad libitum. Daily scores for weight loss, stool consistency, and fecal blood content were averaged to produce a disease activity index as previously described by Friedman and co-workers (DAI, 2009). On day-8 post-treatment, mice were euthanized with 5% isoflurane. Length of colon was measured from cecum to rectum, and epithelial cells were isolated from distal colon by EDTA chelation technique. Histopathology, RNA isolation, and qRT-PCR analyses were performed using standard techniques. Results: Food and water consumption were not significantly altered among the 4 groups of mice. Additional iron supplementation significantly: 1) increased DAI; 2) decreased fecal dry weight; and 3) increased blood inflammatory cytokine levels in UCFe as compared to UC group. Colon length was shortened one-third in UC as compared to NC, but was not further significantly altered by iron supplementation. Loss of crypt architecture and increased influx of inflammatory cells identified in UC colon was not significantly altered in colons from the UCFe group. Expression of apical iron importer DMT1 was increased in UC as compared to NC, but not in the UCFe group. In total, there were no differences due to iron supplementation, and no differences were present due to gender. Conclusion: We conclude that iron supplementation increases the severity of colitis by stimulating water secretion. This study was supported by the National Institute of Health NIDDK DK104791 and DK112085 grants This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

TRPV1 participates in the protective effect of propolis on colonic tissue of ulcerative colitis.

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) mainly characterized by inflammation, ulceration and erosion of colonic mucosa and submucosa. Transient receptor potential vanilloid 1 (TRPV1) is an important mediator of visceral pain and inflammatory bowel disease. This study aims to investigate the protective effect of water soluble propolis (WSP) on UC colon inflammatory tissue and the role of TRPV1. Male SD rats were randomly divided into 6 groups (n=8): a normal control (NC) group, an ulcerative colitis model (UC) group, a low-WSP (L-WSP) group, a medium-WSP (M-WSP) group, a high-WSP (H-WSP) group, and a salazosulfapyridine (SASP) group. The rats in the NC group drank water freely, and the other groups drank 4% dextran sulfate sodium (DSS) solution freely for 7 d to replicate the ulcerative colitis model. Based on the successful replication of the UC, the L-WSP, M-WSP, and H-WSP groups were given 50, 100, and 200 mg/kg of water-soluble propolis by gavage for 7 d, and the SASP group was given 100 mg/kg of sulfasalazine by gavage for 7 d. The body weight of rats in each group was measured at the same time every day, the fecal traits and occult blood were observed to record the disease activity index (DAI). After intragastric administration, the animals were sacrificed after fasted 24 h. Serum and colonic tissue were collected, and the changes of MDA, IL-6 and TNF-α were detected. The pathological changes of colon tissues were observed by HE staining, and the expression of TRPV1 in colon tissues was observed by Western blotting, immunohistochemistry, and immunofluorescence. The animals in each group that drank DSS freely showed symptoms such as weight loss, decreased appetite, depressed state, and hematochezia, indicating that the model was successfully established. Compared with the NC group, DAI scores of other groups were increased (all P<0.05). MDA, IL-6, TNF-α in serum and colon tissues of the UC group were increased compared with the NC group (all P<0.01), and they were decreased after WSP and SASP treatment (all P<0.01). The results of showed that the colon tissue structure was obviously broken and inflammatory infiltration in the UC group, while the H-WSP group and the SASP group significantly improved the colon tissue and alleviated inflammatory infiltration. The expression of TRPV1 in colon tissues in the UC group was increased compared with the NC group (all P<0.01), and it was decreased after WSP and SASP treatment. WSP can alleviate the inflammatory state of ulcerative colitis induced by DSS, which might be related to the inhibition of inflammatory factors release, and down-regulation or desensitization of TRPV1.

Identification of shared gene signatures and molecular mechanisms between chronic kidney disease and ulcerative colitis.

There is a complex interaction between chronic kidney disease (CKD) and ulcerative colitis (UC), but the pathophysiological mechanisms underlying the coexistence of CKD and UC are unclear. This study aimed to investigate the key molecules and pathways that may mediate the co-occurrence of CKD and UC through quantitative bioinformatics analysis based on a public RNA-sequencing database. The discovery datasets of CKD (GSE66494) and UC (GSE4183), as well as validation datasets of CKD (GSE115857) and UC (GSE10616), were downloaded from the Gene Expression Omnibus (GEO) database. After identifying differentially expressed genes (DEGs) with GEO2R online tool, the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses for the DEGs were performed. Next, protein-protein interaction network was constructed with Search Tool for the Retrieval of Interacting Genes (STRING) and visualized by Cytoscape. Gene modules were identified by the plug-in MCODE and hub genes were screened using the plug-in CytoHubba. Then, correlation between immune cell infiltration and hub genes was analyzed, and the receiver operating characteristic curves were used to assess the predictive value of hub genes. Finally, immunostaining of human specimens was used to validate the relevant findings. A total of 462 common DEGs were identified and selected for further analyses. GO and KEGG enrichment analyses indicated that these DEGs were primarily enriched in immune- and inflammation-related pathways. Among them, the PI3K-Akt signaling pathway ranked top in both discovery and validation cohorts, and the key signal molecule phosphorylated Akt (p-Akt) was shown to be significantly overexpressed in human CKD kidneys and UC colons, and further elevated in CKD-UC comorbidity specimens. Moreover, nine candidate hub genes, including CXCL8, CCL2, CD44, ICAM1, IL1A, CXCR2, PTPRC, ITGAX, and CSF3, were identified, of which ICAM1 was validated as a common hub gene. Besides, immune infiltration analysis revealed that neutrophils, macrophages, and CD4+ T memory cells significantly accumulated in both diseases, and ICAM1 was remarkably associated with neutrophil infiltration. Furthermore, intercellular adhesion molecule1 (ICAM1)-mediated neutrophil infiltration was validated to be upregulated in kidney and colon biopsies of CKD and UC patients, and further increased in patients diagnosed with both CKD and UC. Finally, ICAM1 had shown critical value as a diagnostic marker for the co-occurrence of CKD and UC. Our study elucidated that immune response, PI3K-Akt signaling pathway, and ICAM1-mediated neutrophil infiltration might be the common pathogenesis of CKD and UC, and identified ICAM1 as a key potential biomarker and therapeutic target for the comorbidity of these two diseases.

P110 activation protein is strongly expressed in intestinal fibrosis in inflammatory bowel disease patients

Abstract Background Intestinal fibrosis is a common complication of inflammatory bowel disease (IBD) with limited diagnostic modalities to detect and determine the degree of fibrosis. Fibroblast activation protein alpha (FAP) is a protein with both dipeptidyl peptidase and endopeptidase properties which is virtually absent in healthy tissues and has increased expression in chronic inflammatory and fibrotic diseases. In this study, we investigated the presence of FAP in intestinal fibrosis caused by Crohn’s disease (CD) and ulcerative colitis (UC). Methods For this study, transmural surgical resection specimens were retrieved from the Tytgat institute IBD biobank located at Amsterdam University Medical Center. IBD patients undergoing an ileocecal resection for stricturing CD or a subtotal colectomy for therapy-refractory disease, and patients undergoing a right-sided hemicolectomy or ileocecal resection for dysplasia or non-metastasized colorectal cancer (CRC), were included. All patients had an established diagnosis of (CD, UC, dysplasia or CRC) by previous endoscopy and biopsies and had provided informed consent prior to surgery. FAP protein and gene expression levels were determined using immunohistochemistry staining and quantitative polymerase chain reaction (qPCR). Mass cytometry was used to identify FAP–expressing cells. Results In total, 59 ileal and 35 colonic samples were stained and quantified to asses FAP expression (figure 1). A 1.7-fold and 1.9-fold increase of FAP protein expression was seen in inflamed (mean 22.3, p=0.0069); and stenotic (mean 25.5 p=0.0002) CD ileum compared to healthy non-IBD tissue (mean 13.1). Inflamed UC colon (mean 26.8, p = 0.0406) showed a 1.4-fold increase compared to healthy colon (mean 19.2). For the gene expression, 66 ileal and 42 colonic samples were processed and used for qPCR analysis. A 5-fold and 6.4-fold increase of FAP was found in inflamed (mean 0.011, p=0.0475) and stenotic (mean 0.014, p=0.0042) CD ileum, and a 1.7-fold increase was seen in inflamed UC colon (mean 0.278, p=0.0195) compared to controls (means: ileum 0.002; colon 0.165). Conclusion This is the first study reporting the potential of FAP as a fibrotic biomarker not only in stricturing CD, but also in therapy-refractory UC. Significantly increased FAP protein and gene expression is found in inflamed and stenotic ileum in CD and inflamed colon in UC. Additionally, CD90+GP38+ cells have been identified as the most present FAP expressing cells.

Suppression of microRNA-222-3p ameliorates ulcerative colitis and colitis-associated colorectal cancer to protect against oxidative stress via targeting BRG1 to activate Nrf2/HO-1 signaling pathway.

Oxidative stress is an important pathogenic factor in ulcerative colitis (UC) and colitis-associated colorectal cancer (CAC), further impairing the entire colon. Intestinal epithelial cells (IECs) are crucial components of innate immunity and play an important role in maintaining intestinal barrier function. Recent studies have indicated that microRNA-222-3p (miR-222-3p) is increased in colon of UC and colorectal cancer (CRC) patients, and miR-222-3p is a crucial regulator of oxidative stress. However, whether miR-222-3p influences IEC oxidative stress in UC and CAC remains unknown. This study investigated the effect of miR-222-3p on the regulation of IEC oxidative stress in UC and CAC. An in vitro inflammation model was established in NCM460 colonic cells, mouse UC and CAC models were established in vivo, and IECs were isolated. The biological role and mechanism of miR-222-3p-mediated oxidative stress in UC and CAC were determined. We demonstrated that miR-222-3p expression was notably increased in dextran sulfate sodium (DSS)-induced NCM460 cells and IECs from UC and CAC mice. In vitro, these results showed that the downregulation of miR-222-3p reduced oxidative stress, caspase-3 activity, IL-1β and TNF-α in DSS-induced NCM460 cells. We further identified BRG1 as the target gene of miR-222-3p, and downregulating miR-222-3p alleviated DSS-induced oxidative injury via promoting BRG1-mediated activation Nrf2/HO-1 signaling in NCM460 cells. The in vivo results demonstrated that inhibiting miR-222-3p in IECs significantly relieved oxidative stress and inflammation in the damaged colons of UC and CAC mice, as evidenced by decreases in ROS, MDA, IL-1β and TNF-α levels and increases in GSH-Px levels. Our study further demonstrated that inhibiting miR-222-3p in IECs attenuated oxidative damage by targeting BRG1 to activate the Nrf2/HO-1 signaling. In summary, inhibiting miR-222-3p in IECs attenuates oxidative stress by targeting BRG1 to activate the Nrf2/HO-1 signaling, thereby reducing colonic inflammation and tumorigenesis.