Distal Colon Research Articles

Perineuronal net in the extrinsic innervation of the distal colon of mice and its remodeling in ulcerative colitis.

The perineuronal net (PNN) is a well-described highly specialized extracellular matrix structure found in the central nervous system. Thus far, no reports of its presence or connection to pathological processes have been described in the peripheral nervous system. Our study demonstrates the presence of a PNN in the spinal afferent innervation of the distal colon of mice and characterizes structural and morphological alterations induced in an ulcerative colitis (UC) model. C57Bl/6 mice were given 3% dextran sulfate sodium (DSS) to induce acute or chronic UC. L6/S1 dorsal root ganglia (DRG) were collected. PNNs were labeled using fluorescein-conjugated Wisteria Floribunda (WFA) l lectin, and calcitonin gene-related peptide (CGRP) immunofluorescence was used to detect DRG neurons. Most DRG cell bodies and their extensions toward peripheral nerves were found surrounded by the PNN-like structure (WFA+), labeling neurons' cytoplasm and the pericellular surfaces. The amount of WFA+ neuronal cell bodies was increased in both acute and chronic UC, and the PNN-like structure around cell bodies was thicker in UC groups. In conclusion, a PNN-like structure around DRG neuronal cell bodies was described and found modulated by UC, as changes in quantity, morphology, and expression profile of the PNN were detected, suggesting a potential role in sensory neuron peripheral sensitization, possibly modulating the pain profile of ulcerative colitis.

Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer

Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking. To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy. This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021. Invitation to endoscopic screening. Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial. This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death. The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.

To Diet or Not to Diet This Is the Question in Food-Protein-Induced Allergic Proctocolitis (FPIAP)-A Comprehensive Review of Current Recommendations.

Food-protein-induced allergic proctocolitis (FPIAP) is an increasingly reported transient and benign form of colitis that occurs commonly in the first weeks of life in healthy breastfed or formula-fed infants. Distal colon mucosal inflammation is caused by a non-IgE immune reaction to food allergens, more commonly to cow's milk protein. Rectal bleeding possibly associated with mucus and loose stools is the clinical hallmark of FPIAP. To date, no specific biomarker is available, and investigations are reserved for severe cases. Disappearance of blood in the stool may occur within days or weeks from starting the maternal or infant elimination diet, and tolerance to the food allergen is typically acquired before one year of life in most patients. In some infants, no relapse of bleeding occurs when the presumed offending food is reassumed after a few weeks of the elimination diet. Many guidelines and expert consensus on cow's milk allergy have recently been published. However, the role of diet is still debated, and recommendations on the appropriateness and duration of allergen elimination in FPIAP are heterogeneous. This review summarizes and compares the different proposed nutritional management of infants suffering from FPIAP, highlighting the pros and cons according to the most recent literature data.

Tissue-location-specific transcription programs drive tumor dependencies in colon cancer

Cancers of the same tissue-type but in anatomically distinct locations exhibit different molecular dependencies for tumorigenesis. Proximal and distal colon cancers exemplify such characteristics, with BRAFV600E predominantly occurring in proximal colon cancers along with increased DNA methylation phenotype. Using mouse colon organoids, here we show that proximal and distal colon stem cells have distinct transcriptional programs that regulate stemness and differentiation. We identify that the homeobox transcription factor, CDX2, which is silenced by DNA methylation in proximal colon cancers, is a key mediator of the differential transcriptional programs. Cdx2-mediated proximal colon-specific transcriptional program concurrently is tumor suppressive, and Cdx2 loss sufficiently creates permissive state for BRAFV600E-driven transformation. Human proximal colon cancers with CDX2 downregulation showed similar transcriptional program as in mouse proximal organoids with Cdx2 loss. Developmental transcription factors, such as CDX2, are thus critical in maintaining tissue-location specific transcriptional programs that create tissue-type origin specific dependencies for tumor development.

A59 EXPLORING THE ROLE OF ARID1A IN COLONIC HOMEOSTASIS AND REGENERATION

Abstract Background Recent advances in cancer genome analysis have revealed frequently mutated epigenetic regulators as a novel feature in cancer development. Within this context, the Arid1a (AT-rich interactive domain-containing protein 1A) gene, a subunit of the BAF chromatin remodeling complex, has emerged as a frequently mutated gene in many cancers. Additionally, repeated colonic injury caused by diseases such as inflammatory bowel disease (IBD), is also a major risk factor leading to colorectal cancer. Therefore, understanding the connection between colonic epigenetic regulation and its role in response to injury is particularly important for understanding the pathobiology of colorectal cancer. Aims Aim 1: Exploring the role of Arid1a during colonic homeostasis. Mouse model with Arid1a conditionally knocked out in the colon will be analysed at different time points to test whether Arid1a is required during colonic homeostasis. Aim 2: Determining the role of Arid1a during colonic injury and regeneration. Mice will be exposed to a known colitis model to induce colonic injury. Arid1a will be deleted after injury to find out its role during regeneration and recovery from the injury. Methods To examine the effect of Arid1a loss on colonic homeostasis, mice between 6-10 weeks old were injected with 2mg/20g tamoxifen for three days to induce Arid1a knockout using the VilCreERT2; Arid1afl/fl mousseline. Mice were then euthanised using CO2 chamber and analysed 10 days, 3 weeks, and 8 weeks post Arid1a deletion. Histological analysis was performed to examine morphological changes in the colon. To examine the effect of Arid1a on injury caused by colitis, mice were treated with dextran sulfate sodium (DSS) to cause colitis-like injury. Then, Arid1a is deleted by injecting 2mg/20g tamoxifen. Changes in histology and specific cell types will be examined both in the short- and long-term. Results To test whether Arid1a loss alone causes morphological changes in the colon, I compared the crypt lengths between VilCreERT2; Arid1afl/fl mutant mice with their littermate controls and saw that there was no difference in both morphology and length of the crypts. My results show that Arid1a loss in the colon after injury resulted in impaired regeneration characterized by the prolonged loss of goblet cells and cryptal structure in the distal colon. In the long term, Arid1a loss before or after DSS treatment both lead to tumor formation, suggesting that Arid1a is required for colonic regeneration and repair while suppressing tumorigenesis. Conclusions Based on my results, I conclude that Arid1a deletion alone does not cause significant morphological changes in the colon, but this loss affects colonic regeneration and recovery compared to colons with Arid1a intact. In the long term, the dysregulated colonic regeneration may lead to tumorigenesis. Funding Agencies University of Toronto Department of Molecular Genetics

A7 CANNABINOID 1 AND 2 RECEPTOR AGONISTS AND MU-OPIOID RECEPTOR AGONISTS SYNERGISTICALLY INHIBIT COLONIC NOCICEPTION DURING ACUTE COLITIS

Abstract Background Abdominal pain is a debilitating symptom in patients with inflammatory bowel disease. Previously we have shown that combining sub-analgesic doses of cannabinoid 1 receptor (CB1R), but not cannabinoid 2 receptor (CB2R), and mu-opioid receptor (MOR) agonists synergistically inhibits colonic nociception in healthy mice. However, it is unknown whether this combination has analgesic efficacy in a pre-clinical model of colitis. Aims To determine the effects of combining sub-analgesic doses of CBR and MOR agonists on colonic nociception during acute colitis. Methods Colitis was induced in male and female C57BL/6 mice with 2.5% dextran sulfate sodium in drinking water. Extracellular afferent nerve recordings were obtained from ex vivo flat sheet preparations of mouse distal colon. Mechanosensitivity of single afferent axons was assessed via probing of the colon with a 1g von Frey hair before and after superfusion of agonists of CB1R or CB2R plus MOR. To examine effects in vivo, visceromotor response (VMR) to colorectal distention (volume range 20-80 µL) was measured via electromyography. Mice were injected intraperitoneally with vehicle, or a combination of CB1R or CB2R agonist plus morphine 30-minutes prior to VMR experiment. Data were analyzed using a one or two-way ANOVA with Bonferroni test. N denotes number of mice; n denotes number of single afferent axons. Results In afferent nerve recordings, in contrast to healthy mice, the CB2R agonist HU-308 (1 µM and 3 µM) inhibited colonic mechanosensitivity in mice with colitis (1 µM: p<0.01, N=5, n=12; 3 µM: p<0.01, N=7, n=10); a lower concentration (300 nM) had no effect (p=0.52, N=6, n=10). The CB1R agonist ACEA (10 µM) reduced mechanosensitivity during acute colitis (p<0.05, n=11, N=6), whereas 100 nM (p>0.99, n=7, N=5) and 1 µM (p=0.25, n=10, N=6) had no effect. A combination of sub-analgesic concentrations of ACEA (100 nM) and DAMGO (MOR agonist, 1 nM) inhibited colonic mechanosensitivity in healthy mice (p<0.01, N=4, n=8) and during acute colitis (p<0.05, N=6, n=8). While a combination of sub-analgesic concentrations of HU-308 (300 nM) and DAMGO (1 nM) had no effect in healthy mice (p=0.70, N=4, n=8), it inhibited colonic mechanosensitivity during acute colitis (p<0.01, N=8, n=15). In VMR experiments, a combination of a sub-analgesic dose of ACEA (0.3 mg/kg) with morphine (0.3 mg/kg) reduced VMR (p<0.01, N=7) during acute colitis. Similarly, a combination of a sub-analgesic dose of HU-308 (1 mg/kg) and morphine (0.3 mg/kg) reduced VMR (p<0.01, N=6) during acute colitis. Conclusions A CB2R agonist inhibits colonic nociception during acute colitis, but not in healthy mice. A sub-analgesic combination of CB1R and MOR agonists can inhibit pain in healthy and inflamed mice, while combining sub-analgesic CB2R and MOR agonists is only inhibitory during acute colitis. Funding Agencies NRC

A194 EARLY LIFE WESTERN-TYPE DIET ACCELERATES THE ONSET OF MURINE IL-10 KO COLITIS

Abstract Background Early life is a critical time for gut microbiome and immune development, including the establishment of proper host-microbe interactions. While exposures to western world environmental factors are associated with inflammatory bowel disease (IBD) susceptibility, the link between environment in early life and later disease onset is unclear. One of the most important western world environmental factors is diet, which can distinctly alter the gut microbiome. We believe an early life western-type diet (WD) can affect disease progression in a murine IL-10 KO colitis model through dysregulated T-cell responses against the microbiome. Aims We aimed to characterize how an early life WD given to IL-10 KO mice would affect colitis development and the gut microbiome. Methods IL-10 KO mice were housed in specific pathogen free conditions and fed normal chow (NC) or WD ad libitum, either between days 10 to 35 (early WD, eWD) or days 35 to 60 (adolescent WD, aWD). Stool was collected from mice at days 35, 56, and 84 for lipocalin-2 (LCN-2) and 16S rDNA sequencing. Mice were sacrificed at day 84, assessing mesenteric lymph node weight, gene expression, colon damage by histopathology, and colon lamina propria leukocyte (LPL) phenotype and cytokine expression by flow cytometry. Results Compared to NC and aWD, the eWD fed IL-10 KO mice displayed increased fecal LCN-2 at days 56 and 84, indicating greater inflammation. At sacrifice, eWD fed mice had larger mesenteric lymph nodes and more significant colon damage by histopathological scoring. Colon LPL preparations showed that eWD fed IL-10 KO mice had higher proportions and absolute numbers of effector and regulatory T-cells. Additionally, higher proportions and absolute numbers of those T-cells were IFNγ+, IL-17A+, and IL-22+. qPCR of distal colon tissue revealed increased gene expression of innate and type 3 proinflammatory cytokines such as Il1b, Tnfα, and Il23, while showing no change in Il6 and Il4. Taxa positively associated with WD were able to establish a persistent niche in eWD fed mice but not in aWD fed mice. An increase in only one specific taxon was associated with eWD at all timepoints while also most strongly correlating with inflammatory markers. Conclusions This data suggests that eWD feeding during gut microbiome and immune development is uniquely capable of increasing long-term susceptibility to intestinal inflammation in IL-10 KO mice. This appears to be associated with persistent colonization of potentially more inflammatory taxa. This work provides insight into the potential role of early life environmental risk factors, i.e. WD, in the later development of IBD. Funding Agencies CAG, CIHRUniversity of Toronto, Taconic Biosciences

A200 EXPOSURE TO CANNABIS SMOKE IN UTERO AFFECTS THE DEVELOPMENT OF THE ENDOCANNABINOID SYSTEM IN THE GASTROINTESTINAL TRACT

Abstract Background Recreational use of cannabis has been legalized in Canada since 2018. Increasing numbers of women are using cannabis while pregnant, with reported rates ampersand:003E10%. There is a disconnect with societal perceptions, with up to one third of women believing that cannabis is safe for use in pregnancy, but with preclinical and clinical studies demonstrating negative neurodevelopmental outcomes. A key component of gut-brain axis regulation is found in the endocannabinoid system (ECS), of which receptors, ligands and enzymes are extensively distributed throughout the gastrointestinal (GI) tract and are actively involved in GI motility and sensation. Aims We tested the hypothesis that exposure to cannabis smoke in utero could influence the expression of ECS components in the developing GI tract. Methods We developed a “real world” cannabis smoke inhalation model in which CD-1 pregnant mouse dams were exposed daily to a delta-9-tetrahydrocannabinol (THC)-dominant strain of cannabis in a smoking chamber unit, from embryonic days 6 (E6) to E18. Control mice were placed in a restraining cage and exposed to room air for the equivalent time-period. Dams were sacrificed at E18, fetuses removed and the fetal GI tract (from stomach to distal colon) collected for RNA extraction. Key components of the ECS were investigated by developing a NanoString Custom CodeSet, including receptors (cannabinoid receptors 1 and 2; CB1 and CB2, transient receptor potential vanilloid type 1; TRVP1, GPR55) and enzymes (diacylglycerol lipase; DAGL, fatty acid amide hydrolase; FAAH, monoacylglycerol lipase; MAGL, N-acylphosphatidyletanolamine phospholipase D; NAPE-PLD). Samples (n=per litter; 7 cannabis-exposed and 8 control) were processed in the Farncombe Metagenomics Facility and NanoString data analyzed using nSolver Analysis Software. Results We found a significant increase in the expression of ECS receptors in the cannabis-exposed compared to control GI tract at E18, including CB2 (pampersand:003C0.05), TRPV1 (pampersand:003C0.05) and GPR55 (pampersand:003C0.0005). Interestingly, no significant change in mRNA expression was detected for CB1. We also found a significant increase in mRNA encoding the full panel of ECS enzymes, including DAGL (pampersand:003C0.005), FAAH (pampersand:003C0.05), MAGL (pampersand:003C0.05) and NAPE-PLD (pampersand:003C0.005) in cannabis-exposed compared to control GI tract. Conclusions In conclusion, we have found a significant increase in mRNA expression in a panel of key ECS receptors and enzymes in the GI tract at a point of maximal exposure to cannabis in utero. Future research will be needed to further characterize potential impacts on postnatal GI development and function. Funding Agencies CIHRThe Azrieli Foundation

A188 ENHANCED MICROBIAL TRYPTOPHAN METABOLISM ACTIVATES THE ARYL HYDROCARBON RECEPTOR AND AMELIORATES INTESTINAL INFLAMMATION

Abstract Background Intestinal microbiota, diet, and the immune system have been proposed to contribute to the development of inflammatory bowel diseases (IBD). The aryl hydrocarbon receptor (AhR) is a critical regulator of intestinal immunity and mucosal barrier homeostasis that is activated by agonists such as host and microbial tryptophan metabolites. IBD patients have altered microbiota and reduced AhR agonists in intestinal content resulting in downregulation of AhR. Our recent findings indicate that mice harbouring microbiota with impaired tryptophan metabolism and AhR agonist production develop more severe inflammation during colitis. Aims To study the influence of diet-microbe interventions on AhR activation and intestinal inflammation in mice with impaired microbial tryptophan metabolism. Methods Germ-free C57BL/6 mice from McMaster’s Axenic Gnotobiotic Unit were colonized with cecal content of mice harbouring reduced microbiota with impaired tryptophan metabolism with and without tryptophan metabolizing Clostridium sporogenes. Following three weeks of microbial stabilization, mice were provided a high tryptophan (HT) diet or a low tryptophan (LT) diet as a control. Experimental colitis was induced using dextran sulfate sodium in drinking water (DSS; 2.5% w/v). Briefly, DSS was provided ad libitum for five days, followed by two days of recovery before tissue collection. Activation of AhR was measured in stool and C. sporogenes cultures using an in vitro AhR luciferase reporter assay. AhR agonists were quantified by capillary-electrophoresis-mass spectrometry. Colonic expression of AhR pathway genes was evaluated by RT-qPCR. Susceptibility to colitis was assessed by histologic analysis of distal colon sections, fecal lipocalin-2, weight loss, and clinical scores. Inflammatory gene transcripts were quantified in colon tissue by Nanostring. Results C. sporogenes efficiently produces AhR agonists in vitro and in vivo. In mice with impaired tryptophan metabolism, the HT diet increased AhR agonists in intestinal content and colonic AhR pathway gene expression, which was further enhanced in mice colonized with C. sporogenes. Compared to mice fed LT and HT diets, mice colonized with C. sporogenes and fed HT were most protected from weight loss, tissue damage, and immune cell infiltration. Conclusions These findings highlight the potential of tryptophan-rich diets and targeted microbe interventions as a novel approach to enhance AhR activation and mitigate inflammation during colitis. Consequently, exploring methods to improve tryptophan metabolism through diet and manipulation of the microbiota could be a promising therapeutic avenue for IBD patients with impaired AhR activation. Funding Agencies CCC, CIHR

Comparing surface electroenterography measurements between patients suffering from Hirschsprung’s disease and controls: a feasibility study

Current diagnostics in Hirschsprung’s disease are often challenging and invasive. This study aims to investigate whether surface electroenterography can non-invasively discern healthy subjects from subjects suffering from Hirschsprung’s disease. Nine healthy subjects (seven children, two adults) and eleven subjects suffering from surgically untreated Hirschsprung’s disease (nine children, two adults) underwent an electroenterography procedure. This procedure consisted of ultrasound-guided placement of surface electrodes on the abdomen covering all parts of the colon, fasting and two 20-min electroenterography measurements separated by a meal. The dominant frequency, magnitude and relative increase (pre- to postprandial) of colonic activity were compared between both groups. The results showed that in the pediatric group, no significant differences in dominant frequency, colonic activity and relative power increase were observed between controls and patients. The adult patients showed decreased colonic motility and relative power increase in the electrodes closest to the distal colon, both when compared to the same electrodes in controls and to the more proximal electrodes of themselves. To conclude, electroenterography measurements in young children is challenging, but the results in adults demonstrate that these measurements can possibly distinguish between controls and Hirschsprung’s patients. Therefore, optimization of electroenterography measurements in young children is necessary.

Saccharomyces cerevisiae derived postbiotic alters gut microbiome metabolism in the human distal colon resulting in immunomodulatory potential in vitro.

The yeast-based postbiotic EpiCor is a well-studied formulation, consisting of a complex mixture of bioactive molecules. In clinical studies, EpiCor postbiotic has been shown to reduce intestinal symptoms in a constipated population and support mucosal defense in healthy subjects. Anti-inflammatory potential and butyrogenic properties have been reported in vitro, suggesting a possible link between EpiCor's gut modulatory activity and immunomodulation. The current study used a standardized in vitro gut model, the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®), to obtain a deeper understanding on host-microbiome interactions and potential microbiome modulation following repeated EpiCor administration. It was observed that EpiCor induced a functional shift in carbohydrate fermentation patterns in the proximal colon environment. Epicor promoted an increased abundance of Bifidobacterium in both the proximal and distal colon, affecting overall microbial community structure. Co-occurrence network analysis at the phylum level provided additional evidence of changes in the functional properties of microbial community promoted by EpiCor, increasing positive associations between Actinobacteria with microbes belonging to the Firmicutes phylum. These results, together with a significant increase in butyrate production provide additional support of EpiCor benefits to gut health. Investigation of host-microbiome interactions confirmed the immunomodulatory potential of the applied test product. Specific microbial alterations were observed in the distal colon, with metabotyping indicating that specific metabolic pathways, such as bile acid and tryptophan metabolism, were affected following EpiCor supplementation. These results, especially considering many effects were seen distally, further strengthen the position of EpiCor as a postbiotic with health promoting functionality in the gut, which could be further assessed in vivo.

Polyphenol- and Glucuronoxylan-Rich Fiber Extract from Birch (Betula sp.) Wood Regulates Colonic Barrier Function and Cell Proliferation in Healthy Rats.

Birch wood-derived fiber extracts containing glucuronoxylans (GX) and polyphenols show potential for various food technological applications. This study investigated the effect of two extracts, GXpoly and pureGX, differing in lignin content on colonic barrier function. Healthy rats were fed diets containing 10% GXpoly, pureGX, or cellulose for 4 weeks. Colon crypt depth was lower in the GX groups than in the control group, but in the proximal colon, the result was significant only in GXpoly. An artificial intelligence approach was established to measure the mucus content and goblet cells. In the distal colon, their amounts were higher in the control group than in the GX groups. All diets had a similar effect on the expression of the tight junction proteins occludin, claudin-1, and claudin-7. GXpoly enhanced the fecal IgA production. Our results suggest that GX-rich extracts could support the colonic barrier and work as functional food ingredients in the future.

Gene coexpression networks reveal a broad role for lncRNAs in inflammatory bowel disease.

The role of long noncoding RNAs (lncRNAs) in disease is incompletely understood, but their regulation of inflammation is increasingly appreciated. We addressed the extent of lncRNA involvement in inflammatory bowel disease (IBD) using biopsy-derived RNA-sequencing data from a large cohort of deeply phenotyped patients with IBD. Weighted gene correlation network analysis revealed gene modules of lncRNAs coexpressed with protein-coding genes enriched for biological pathways, correlated with epithelial and immune cell signatures, or correlated with distal colon expression. Correlation of modules with clinical features uncovered a module correlated with disease severity, with an enriched interferon response signature containing the hub lncRNA IRF1-AS1. Connecting genes to IBD-associated single nucleotide polymorphisms (SNPs) revealed an enrichment of SNP-adjacent lncRNAs in biologically relevant modules. Ulcerative colitis-specific SNPs were enriched in distal colon-related modules, suggesting that disease-specific mechanisms may result from altered lncRNA expression. The function of the IBD-associated SNP-adjacent lncRNA IRF1-AS1 was explored in human myeloid cells, and our results suggested IRF1-AS1 promoted optimal production of TNF-α, IL-6, and IL-23. A CRISPR/Cas9-mediated activation screen in THP-1 cells revealed several lncRNAs that modulated LPS-induced TNF-α responses. Overall, this study uncovered the expression patterns of lncRNAs in IBD that identify functional, disease-relevant lncRNAs.

Age-, sex- and proximal–distal-resolved multi-omics identifies regulators of intestinal aging in non-human primates

The incidence of intestinal diseases increases with age, yet the mechanisms governing gut aging and its link to diseases, such as colorectal cancer (CRC), remain elusive. In this study, while considering age, sex and proximal–distal variations, we used a multi-omics approach in non-human primates (Macaca fascicularis) to shed light on the heterogeneity of intestinal aging and identify potential regulators of gut aging. We explored the roles of several regulators, including those from tryptophan metabolism, in intestinal function and lifespan in Caenorhabditis elegans. Suggesting conservation of region specificity, tryptophan metabolism via the kynurenine and serotonin (5-HT) pathways varied between the proximal and distal colon, and, using a mouse colitis model, we observed that distal colitis was more sensitive to 5-HT treatment. Additionally, using proteomics analysis of human CRC samples, we identified links between gut aging and CRC, with high HPX levels predicting poor prognosis in older patients with CRC. Together, this work provides potential targets for preventing gut aging and associated diseases.

Adult Height and Risk of Colorectal Cancer: A Pooled Analysis of 10 Population-based Cohort Studies in Japan.

While tall stature has been linked to an increase in the risk of colorectal cancer (CRC), its association with cancer in the colorectum and its subsites remains unclear among Asians. We conducted a pooled analysis of 10 population-based cohort studies among adults in Japan. Each study estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for CRC incidence associated with adult height were estimated using Cox proportional hazards regression with adjustment of the same set of covariates were then pooled to estimate summary HRs incidence using random-effect models. We identified 9,470 CRC incidences among 390,063 participants during 5,672,930 person-years of follow-up. Men and women with tall stature had a higher risk of CRC and colon cancer. HRs for CRC, colon cancer, and distal colon cancer for the highest versus lowest height categories were 1.23 (95% CI, 1.07-1.40), 1.22 (95% CI, 1.09-1.36), and 1.27 (95% CI, 1.08-1.49), respectively, in men and 1.21 (95% CI, 1.09-1.35), 1.23 (95% CI, 1.08-1.40), and 1.35 (95% CI, 1.003-1.81), respectively, in women. The association with proximal colon cancer and rectal cancer was less evident in both sexes. This pooled analysis confirms the link between tall stature and a higher risk of CRC and colon cancer (especially distal colon) among the Japanese and adds evidence to support the use of adult height to identify those at a higher risk of CRC.

Gastric Perineurioma: A Rare Entity with Molecular Analysis and Literature Review.

Perineuriomas of the gastrointestinal tract are benign neoplasms that commonly develop in the distal colon and are identified during screening colonoscopy; however, perineuriomas of the stomach are exceedingly rare and less frequently identified. Differentiating gastric perineuriomas from other more serious gastric neoplasms is critical to avoid unnecessarily aggressive treatments. Thus far, only six patients with gastric perineurioma have been described, and the molecular characterization of this entity is still lacking. We report a 52-year-old woman who presented with abdominal pain and gastric acid reflux and was found to have a 1.5 cm subepithelial gastric neoplasm composed of bland spindle cells displacing the gastric glands with no cytologic atypia or mitotic activity, suggesting a benign spindle cell neoplasm. Immunohistochemical analysis showed reactivity for perineurial markers glucose transporter-1 and epithelial membrane antigen, consistent with benign gastric perineurioma. DNA extracted from the tissue was used for a capture-based target sequence enrichment panel followed by Illumina next-generation sequencing and targeted bioinformatic analysis for oncogenic alterations within defined disease-associated target regions. No sequence variants in the BRAF gene were identified. This rare case of gastric perineurioma helps solidify our understanding of how to discern various types of gastric neoplasms through traditional laboratory analysis alongside genetic sequencing approaches. Although extremely rare, gastric perineurioma should be kept in the differential diagnosis when assessing spindle cell gastric tumors to avoid unnecessary therapies, and physicians should understand the molecular characteristics of benign versus malignant tumors.

Combined laparoscopic and endoscopic method for foreign body removal from descending colon: A case report

BACKGROUND The majority of published reports on foreign bodies (FBs) involve the rectum and applied a transanal retrieval. Usually, patients with FB above the rectum are subjected to laparotomy for removal. Here, we illustrate the case of a man with an FB that had migrated into the descending colon, and its successful removal via a laparoscopic approach. CASE SUMMARY A 43-year-old man, who had the habit of FB insertion into his anus to aid defecation, presented upon experience of such an FB slipping through and migrating upward to the distal colon. Plain abdominal radiograph revealed a bottle-shaped FB, positioned in the left iliac fossa region. The FB was successfully removed via a laparoscopic-assisted procedure in which we combined diagnostic laparoscopic and endoscopic techniques during surgery. The patient was monitored for 2 d postoperatively and subsequently discharged home. CONCLUSION A minimally invasive approach should be adopted to aid extraction of colorectal FB as it is effective and safe.

The Role of Beclin 1 and HER2 in Colorectal Carcinoma; An Immunohistochemical Study.

This study aimed to evaluate the expression of Beclin 1 and HER2 proteins using immunohistochemistry in CRC tissues compared to colonic adenoma, and to investigate the correlation of their expression with clinicopathological parameters and survival outcomes in CRC patients. The study utilized paraffin-embedded blocks from 17 colonic adenoma and 81 CRC cases. Immunohistochemical analysis was performed to assess the expression of Beclin 1 and HER2 proteins. The cytoplasmic expression of Beclin 1 was significantly higher in CRC tissues compared to adenoma specimens (P=0.051). High Beclin 1 expression was significantly associated with distal colon location (P=0.028). High HER2 cytoplasmic expression was significantly associated with vascular invasion (P=0.05), perineural invasion (P=0.03), and shorter overall survival (P=0.035). The findings suggest that Beclin 1 plays a role in colorectal carcinogenesis, with higher expression observed in CRC cases compared to adenoma cases. Furthermore, HER2 carries poor prognostic impact in CRC cases.

The Eleutherococcus senticosus fruits' intractum affects changes in the transepithelial electric potential in the distal section of the rabbit's large intestine and inhibits hyaluronidase

Ethnopharmacological relevanceEleutherococcus senticosus (Rupr. et Maxim.) Maxim. has been used in traditional Russian medicine due to its recognized immunostimulant and anti-inflammatory activities. Compounds present in the fruits have demonstrated the capability to modulate the activity of enzymes such as hyaluronidase, suggesting their potential value in the development of effective therapies for various conditions where anti-inflammatory properties are beneficial, such as gastrointestinal diseases and tumor growth. Aim of the studyIn order to support the use of the fruits in folk medicine, this study is aimed to evaluate, post-mortem, the impact of E. senticosus fruits intractum (40 % extract made from fresh fruits) on the transepithelial electrogenic transport of sodium ions in the colon. The objective of this study was also to examine the impact of the intractum on proinflammatory serum hyaluronidase in children diagnosed with acute leukemia. MethodsThe study employed the Ussing technique to examine electrophysiological characteristics of isolated epithelial tissue, using the distal colon wall isolated from 10 New Zealand white male rabbits. The effect of the intractum on the inhibition of human serum hyaluronidase was examined with turbidimetric screening methods, using the blood samples collected from patients diagnosed with acute leukemia. ResultsFor the first time, we discovered that the intractum used in the stimulation fluid, caused hyperpolarization reactions in colon tissue. Statistical analysis showed that these reactions were significantly different in relation to the control. The intractum significantly inhibited hyaluronidase activity with the mean value by group of 60 %, and 40 % for aescin used as a control. ConclusionThe results support the traditional use of the fruits in inflammatory-related diseases. The use of intractum of E. senticosus on the distal colon wall demonstrates its protective effect on the wall integrity and in a relation to hyaluronidase inhibition may additionally indicate its anti-inflammatory property. Thus, the results mean that the intractum may be used in colon-related diseases.

Exclusive Enteral Nutrition Beneficially Modulates Gut Microbiome in a Preclinical Model of Crohn's-like Colitis.

Exclusive enteral nutrition (EEN) is an established dietary treatment for Crohn's disease (CD) by alleviating inflammation and inducing remission. However, the mechanisms of action of EEN are incompletely understood. As CD is associated with gut microbiome dysbiosis, we investigated the effect of EEN on the microbiome in a rat model of CD-like colitis. The rat model of CD-like colitis was established by an intracolonic instillation of TNBS at 65 mg/kg in 250 µL of 40% ethanol. Sham control rats were instilled with saline. Rats were fed ad libitum with either regular pellet food or EEN treatment with a clear liquid diet (Ensure). Rats were euthanized at 7 days. Fecal pellets were collected from the distal colon for 16S rRNA sequencing analysis of gut microbiota. In addition, colon tissues were taken for histological and molecular analyses in all the groups of rats. EEN administration to TNBS-induced CD rats significantly improved the body weight change, inflammation scores, and disease activity index. The mRNA expression of IL-17A and interferon-γ was significantly increased in the colonic tissue in TNBS rats when fed with regular food. However, EEN treatment significantly attenuated the increase in IL-17A and interferon-γ in TNBS rats. Our 16S rRNA sequencing analysis found that gut microbiota diversity and compositions were significantly altered in TNBS rats, compared to controls. However, EEN treatment improved alpha diversity and increased certain beneficial bacteria such as Lactobacillus and Dubosiella and decreased bacteria such as Bacteroides and Enterorhabdus in CD-like rats, compared to CD-like rats with the regular pellet diet. In conclusion, EEN treatment increases the diversity of gut microbiota and the composition of certain beneficial bacteria. These effects may contribute to the reduced inflammation by EEN in the rat model of CD-like colitis.