Colitis Colon Research Articles

18 A HUMAN-DERIVED 5-MER PEPTIDE (MTADV), WHICH RESTRICTIVELY ALLEVIATES THE PRO-INFLAMMATORY ACTIVITY OF SERUM AMYLOID A (SAA), SUBSTANTIALLY AMELIORATES IBD PATHOLOGY: NEW POTENTIAL DRUG (MTADV) AND THERAPEUTIC TARGET CANDIDATE (SAA) FOR IBD

Abstract A human anti-inflammatory 5-MER peptide MTADV (methionine-threonine-alanine-aspartic acid-valine) derived from a sequence of a pro-inflammatory CD44 variant was first described by us in Nedvetzki et al., J. Clin. Invest. 111,1211-1220, 2003. A NCBI BLAST RefSeq protein sequence database, that contains at present 81,347 human protein sequences, reveals that only one additional protein contains this unique MTADV sequence of alternating hydrophobic and hydrophilic amino acids. This human peptide displays an efficient anti-inflammatory effect in Inflammatory Bowel Disease (IBD), Rheumatoid Arthritis and Multiple sclerosis mouse models, all share amyloid proteins in the relevant target organs. We show here that the 5-MER peptide, administered after the onset of disease,either by SC injections or oral delivery, inhibited the pathological activity of two IBD models (TNBS and DSS), as indicated by histopathology analysis (Ameho’s score) or Bioluminescence Imaging, sensing the release of Reactive Oxdative Species (ROS), which reflect colon inflammation (Fig 1). The 5-MER MTADV peptide, while inhibiting chronic inflammation, neither interferes with normal immune responses nor induce neutralizing antibodies. A pull-down experiment with mass spectrometric analysis revealed that the 5-MER peptide specifically binds to serum amyloid A (SAA), a stress pro-inflammatory protein, which generates aggregated amyloid deposits in the IBD colon (de Villiers at al Cytokine 12:1337-1347,2000). Our studies further provide in vitro evidence, strengthened by in vivo experiments, that SAA is a significant target of this pentamer. To this end, the 5-MER peptide (but not the corresponding scrambled peptide) inhibits the release of the pro-inflammatory cytokines IL-6 and IL-1β from SAA-activated fibroblasts. Furthermore, the 5-MER peptide was found to retard the early stages of amyloid-type aggregation of SAA in solution (Fig 2). Adopting the β-sheet conformation, MTADV would display opposing hydrophobic and hydrophilic faces that could interact with the β-sheet-forming amyloidogenic sequences in SAA. This suggests that the mechanism of action for the 5-MER peptide in vivo may depend on its ability to slow the aggregation of SAA, thus reduce its contribution to chronic inflammation. Finally, using bioinformatics and qRT-PCR, we have found the pentamer up-regulates set of genes involved in resistance to chronic inflammations. Hence, our study provides both a new potential drug (MTADV) and a new therapeutic target candidate (SAA) for IBD.

14 COLONIC EPITHELIAL CELL-SPECIFIC AFTIPHILIN KNOCKDOWN REGULATES EPITHELIAL BARRIER FUNCTION THROUGH MYOSIN LIGHT CHAIN-ASSOCIATED ACTIN ORGANIZATION IN VITRO AND INTESTINAL LENGTH IN VIVO

Abstract Background and Aims Colonic epithelial integrity is often compromised during colonic inflammation and Inflammatory Bowel Disease. Aftiphilin (AFTPH) is a downstream target of microRNA-133a and its expression is reduced in colonic tissues of wild type mice from experimental colitis models and colonic biopsies from patients with ulcerative colitis. We have previously shown that AFTPH is involved in regulating intestinal epithelial barrier function and actin organization in human colonic epithelial cells in vitro (DDW 2016). On the other hand, our results suggested that global aftiphilin knock-out is embryonic lethal in mouse models (DDW 2019). Here, we further examined the role of AFTPH in regulating actin organization in vitro and characterize the colonic epithelial cell-specific aftiphilin knock-out mice. Methods Human colonic epithelial NCM460 cells were transfected with si-RNA against AFTPH to achieve transient AFTPH gene-silencing. Stable AFTPH knock-down clones were generated by transducing Caco2-BBE cells with recombinant lentivirus carrying sh-AFTPH or control sh-RNA. To create intestinal epithelial cell-specific aftiphilin knock-out mice, Aftph flox/flox mice were cross-bred with B6.Cg-Tg(Vil1-cre)997Gum/J mice, which express Villin-driven Cre recombinase (Vil-Cre), to generate intestinal epithelial cell-specific aftiphilin knock-out mice (Aftph Vil-/Vil-). Protein expression of F- and G-actin and p70S6K were detected using Western blot. Tissues from various organs were collected with Aftph Vil-/Vil- and its wildtype counterparts at 12 weeks. Results Results from western blot analysis showed that F-/G-actin ratio in AFTPH gene-silenced NCM460 cells were 0.6±0.17 fold, when compared to the treatment control. In addition, AFTPH gene-silencing in human colonic epithelial cells activated p70S6K, a kinase that is involved in actin organization, when compared to treatment control (1.2±0.15 vs. 2.0±0.15, p=0.0354). Furthermore, transepithelial electric resistance (TER) of Caco2-BBE cells deficient in AFTPH is significantly lower than that of control cells (0.5±0.07 fold). Lastly, in vivo intestinal epithelial cell-specific Aftph knock-out increased the length of small intestine, when compared to that of wild type mice (30.7±0.33 vs. 34.8±0.97, p=0.02), while the tissue weight of spleen to body weight was reduced (0.30±0.011 vs. 0.26±0.006, p=0.0169). Summary and Conclusions Our results indicate that AFTPH directly regulates epithelial barrier function and actin organization through mediating F-/G-actin ratio in human colonic epithelial cells, possibly through p70S6K. Importantly, intestinal epithelial cell-specific knock-out in vivo increased intestinal length and reduced size of the spleen. Our results suggested that AFTPH is crucial in regulating colonic epithelial barrier function in vitro and intestinal homeostasis.

Role of the δ-Opioid Receptor in 2 Murine Models of Colitis.

Crohn disease and ulcerative colitis, collectively referred to as inflammatory bowel disease (IBD), are chronic inflammatory disorders of the gastrointestinal tract. Currently, the etiology of IBD is unknown, and immunosuppressive therapies have become the standard of care to reduce the inflammation; however, these agents only induce remission 50% of the time in patients and can have serious side effects. Recently, endogenous opioids and opioid receptors have been shown to play a role in the mediation of inflammation. In addition, opioid receptor blockade with a nonselective antagonist, naltrexone, has been shown to reduce colitis in both murine models and human subjects. The goal of the current study was to determine if the antiinflammatory effects of naltrexone are mediated through the delta (δ) opioid receptor. Male C57BL/6NCrl (6 to 8 wk.; n = 110) and female BALB/cAnNCrl (6-8 wk.; n = 91) mice were studied using 2 animal models of chemically induced colitis: dextran sodium sulfate (DSS) and 2, 4, 6-trinitrobenzenesulfonic acid (TNBS). The selective δ-receptor antagonists naltrindole and 7-benzylidenenaltrexone were administered to examine the role of the δ-opioid receptor in colonic inflammation. The quantitative measurement of colitis activity, colon weight and length, Hct, WBC count, and gross and microscopic aberrations were analyzed. Administration of naltrexone in the DSS colitis model significantly improved overall disease activity indices on day 5 of therapy. The use of δ-antagonists and naltrexone had limited to no effect on TNBS colitis. Similar findings were obtained by using the DSS colitis model. Based on the current findings, the authors conclude that naltrexone therapy has limited effect on the improvement of colitis in 2 murine models; however, the δ-opioid receptor was not responsible for mediating the effects.

Ulcerative colitis induced with acetic acid is ameliorated by Antrocaryon micraster through reduced serum levels of tumor necrosis factor alpha and interleukin-6 in sprague dawley rats

Background: Antrocaryon micraster possesses significant antioxidant and anti-inflammatory activities. These properties are shared by medicinal plants that have demonstrated beneficial effects in the treatment of ulcerative colitis. Objectives: To assess the effect of the total ethanol stem bark of A. micraster extract (AME) on damage to the rat colon in acetic acid-induced colitis. Materials and Methods: Rats were pretreated with sulphasalazine 500 mg/kg or AME 30, 100, and 300 mg/kg daily for 3 days after which colitis was induced in test animals with acetic acid (4% V/V). Rats were sacrificed 24 h later and blood samples were obtained for hematological and cytokine assays. Colons were dissected for assessment of macroscopic and microscopic damage. Results: AME treatment modified hematological parameters and reduced serum levels of tumor necrosis factor alpha and interleukin-6. Macroscopic assessment showed that AME reduced mucosal erythema, edema, erosions, bleeding, and ulceration. Histology showed preserved mucosal architecture, reduced inflammatory cell infiltration, decreased mucosal thickening, preserved goblet cell numbers, and inhibition of mast cell proliferation and degranulation in the colons. Conclusion: Taken together, the total ethanol stem bark AME exerts ameliorative effects on damage to the rat colon in acetic acid-induced colitis.

Stachyose modulates gut microbiota and alleviates dextran sulfate sodium-induced acute colitis in mice

Background/Aim:Ulcerative colitis (UC) has been implicated to imbalanced enteric flora and reduced microbial diversity. Stachyose is a kind of natural prebiotic which favorably modulate the composition of the gut microbiota. The present study aims to investigate the effects of stachyose on inflammatory levels and gut microbiota of acute colitis mice.Materials and Methods:In this study, the mice were randomly divided into four groups: (1) control group; (2) stachyose group; (3) dextran sulfate sodium (DSS) group; (4) stachyose + DSS group. Hemotoxylin and Eosin (H and E) staining was performed for the distal colon to examine the inflammation and tissue damage. The inflammatory cytokines including IL-6, IL-10, IL-17a, and TNF-α in serum were determined by ELISA assay. The differences in the gut microbiota were analyzed by 16S rDNA gene sequencing.Results:Histological assay showed that the stachyose treatment significantly reduced the lesions of the colon in DSS-induced colitis. And the upregulated inflammatory cytokines induced by DSS were significantly inhibited by stachyose treatment. Additionally, the sequencing analysis showed that the stachyose changed the gut microbiota composition with a higher level of Akkermansia, as well as selectively increasing some probiotics, including Lactobacillus.Conclusions:Our results suggested that stachyose increased beneficial microbiota and bacterial diversity to alleviate acute colitis in mice, which might be a new promising option to UC patients.

Sturgeon hydrolysates alleviate DSS-induced colon colitis in mice by modulating NF-κB, MAPK, and microbiota composition.

Sturgeon muscle byproduct collected after caviar production is usually not fully utilized, and sometimes may be discarded, thus causing a lot of waste. Yet dietary protein hydrolysates, which may be derived from sturgeon muscle, have been reported to have versatile beneficial biological activities. Studying the biological activities of sturgeon muscle-derived hydrolysates holds much promise for adding value to sturgeon. The current study aimed to study the therapeutic anti-inflammatory effects of sturgeon muscle-derived hydrolysates and the underlying mechanisms. The administration of sturgeon hydrolysates (SH) significantly decreased the severity of DSS-induced damage, evidenced by increased body weight, colon length, and decreased disease activity index (DAI) and histological scores. SH also inhibited myeloperoxidase (MPO) activity and reduced the serum levels of IL-6, IL-1β, and TNF-α. Western blotting results revealed that SH suppressed DSS-induced activation of the NF-κB and MAPK pathways in the colon. Furthermore, SH partially restored the alteration of the gut microbiota in colitic mice. SH increased the Bacteroidetes/Firmicutes ratio and the relative abundance of Ruminococcaceae, Porphyromonadaceae, and Bacteroidetes S24-7, while decreased the abundance of potentially harmful bacteria Erysipelotrichaceae and Enterococcaceae. These results suggest that SH inhibited DSS-induced colitis by regulating the NF-κB and MAPK pathways and modulating microbiota composition.

Triclocarban exposure exaggerates colitis and colon tumorigenesis: roles of gut microbiota involved

ABSTRACT Triclocarban (TCC) is a widely used antimicrobial ingredient in consumer products and is a ubiquitous contaminant in the environment. In 2016, the FDA removed TCC from over-the-counter handwashing products, but this compound is still approved for use in many other personal care products. A better understanding of its impact on human health could lead to significant impact for public health and regulatory policies. Here we show that exposure to low-dose TCC exaggerated the severity of colitis and exacerbated the development of colitis-associated colon tumorigenesis, via gut microbiota-dependent mechanisms. Exposure to TCC increased dextran sodium sulfate (DSS)- and interleukin 10 (IL-10) knockout-induced colitis, and exaggerated azoxymethane (AOM)/DSS-induced colon tumorigenesis in mice. Regarding the mechanisms, TCC exposure reduced the diversity and altered the composition of gut microbiota and failed to promote DSS-induced colitis in mice lacking the microbiota, supporting that the presence of the microbiota is critical for the pro-colitis effects of TCC. Together, these results support TCC could be a novel risk factor for colitis and colitis-associated colon cancer, and further regulatory policies on this compound could be needed.

Long-Chain Polyphosphate Is a Potential Agent for Inducing Mucosal Healing of the Colon in Ulcerative Colitis.

The goal of ulcerative colitis (UC) treatment has recently been shown to be “mucosal healing,” as no drug directly induces mucosal healing. Probiotics possess sufficient safety, but their efficacy in the treatment of UC remains controversial because of the influence of intestinal conditions. It is believed that the identification of bioactive molecules produced by probiotics and their application will help to solve this issue. We therefore identified a probiotic‐derived long‐chain polyphosphate as a molecule enhancing the intestinal barrier function. This study demonstrated that long‐chain polyphosphate exhibited antiinflammatory effects in a human macrophage and interleukin‐10 knockout transfusion mouse model. The first‐in‐human trial showed that 7 of the 10 enrolled patients acquired clinical remission, 4 of whom achieved endoscopic remission despite a history of treatment with anti–tumor necrosis factor (TNF)–α agents. No adverse reactions were observed. Long‐chain polyphosphate might be useful for the treatment of refractory UC, even in patients with failure or intolerance to anti‐TNF‐α therapy.

Protective Role of Fecal Microbiota Transplantation on Colitis and Colitis-Associated Colon Cancer in Mice Is Associated With Treg Cells.

Colitis-associated cancer (CAC) is the most serious outcome of inflammatory bowel disease, which has an alteration of commensal intestinal microbiota. However, the role of intestinal microbiota on CAC progression is not well-understood. Fecal microbiota transplantation (FMT) was used for treating murine azoxymethane–dextran sodium sulfate (AOM-DSS) model of CAC. Composition of gut microbiota during FMT treatment was analyzed. RT-PCR and ELISA were used to detect the inflammatory factors, and immunofluorescence was applied to examine the phospho-nuclear factor (NF)-κB p65/p100 and Ki67-positive cells in the colons. In addition, flow cytometry was performed to analyze the immune cell after FMT treatment. Rehabilitation of the intestinal microbiota by FMT restored both the ratio and diversity of microbiota during CAC progression. Remarkably, a favorable morphometric outcome characterized by decreased tumor load and size was observed in CAC mice with FMT treatment. In addition, an anti-inflammatory function of FMT was demonstrated by decreasing pro-inflammatory factors but increasing anti-inflammatory factors through inhibiting canonical NF-κB activity and cellular proliferation in colons of CAC mice. The expression of CD4+CD25+Foxp3+ regulatory T cells (Tregs) was significantly increased after FMT treatment in CAC mice, but not T helper (Th)1/2/17 cells. Our study aids in the understanding of CAC pathogenesis and reveals a previously unrecognized role for FMT in the treatment of CAC through restoring the intestinal microbiota and inducing regulatory T cells.

Calcium-activated chloride channel regulator 1 (CLCA1): More than a regulator of chloride transport and mucus production

CLCA1 is a member of the CLCA (calcium-activated chloride channel regulator) family and plays an essential role in goblet cell mucus production from the respiratory tract epithelium. CLCA1 also regulates Ca2+-dependent Cl− transport that involves the channel protein transmembrane protein 16A (TMEM16A) and its accessary molecules. CLCA1 modulates epithelial cell chloride current and participates in the pathogenesis of mucus hypersecretory-associated respiratory and gastrointestinal diseases, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, pneumonia, colon colitis, cystic fibrosis intestinal mucous disease, ulcerative colitis, and gastrointestinal parasitic infection. Most studies have been focused on the expression regulation of CLCA1 in human specimens. Limited studies used the CLCA1-deficient mice and CLCA1 blocking agents and yielded inconsistent conclusions regarding its role in these diseases. CLCA1 not only regulates mucin expression, but also participates in innate immune responses by binding to yet unidentified molecules on inflammatory cells for cytokine and chemokine production. CLCA1 also targets lymphatic endothelial cells and cancer cells by regulating lymphatic cell proliferation and lymphatic sinus growth in the lymphatic organs and controlling cancer cell differentiation, proliferation, and apoptosis, all which depend on the location of the lymphatic vessels, the type of cancers, the presence of Th2 cytokines, and possibly the availability and type of CLCA1-binding proteins. Here we summarize available studies related to these different activities of CLCA1 to assist our understanding of how this secreted modifier of calcium-activated chloride channels (CaCCs) affects mucus production and innate immunity during the pathogenesis of respiratory, gastrointestinal, and malignant diseases.

Injected laquinimod D-α-tocopheryl polyethylene glycol-1000 succinate polymeric micelles for the treatment of inflammatory bowel disease

Inflammatory bowel diseases (IBDs) are chronic relapsing disorders of the gastrointestinal tract characterized pathologically by intestinal inflammation and epithelial injury. Laquinimod (LAQ), a poorly water-soluble compound, was proved to be effective for colitis remission at low dose of 0.5 mg/kg in patients with Crohn’s disease. Due to its extremely low solubility in water, it was difficult to develop an injectable liquid dosage form. Herein, D-α-Tocopheryl polyethylene glycol-1000 succinate (TPGS) polymeric micelles were developed as a delivery vehicle of LAQ for the management of inflammatory bowel disease. Using the LAQ/TPGS ratio of 1:100, LAQ-loaded micelles were successfully prepared by thin-film dispersion method. The solubility of LAQ in water was significantly increased from 10.5 μg/mL in pure water to 500 μg/mL in TPGS micelles. LAQ-loaded micelles of TPGS exhibited the fine particle size of 34.6 nm and Zeta potential of -0.67 mV. Moreover, the good stability of LAQ-loaded micelles in physiology-mimicking medium was confirmed by detecting their particle size, zeta potential and leakage of the loading drug. Therapeutic effect of LAQ-loaded micelles on DSS-induced mice was proved by detecting DAI score, colon length and loss of body weight. Moreover, the morphology and colonic mucosal barrier of the injured colon of DSS-induced mice was largely recovered after treatment with LAQ-loaded micelles. Meanwhile, the inflammation of colitis colon was also obviously alleviated by LAQ-loaded micelles. Conclusively, polymeric micelles of TPGS may be a promising delivery vehicle of LAQ for the management of inflammatory bowel disease.

317 Increased Interval Between Screening and Surveillance Colonoscopy Is Associated With Decreased Withdrawal Time

INTRODUCTION: Colonoscopy is currently the most effective method for prevention of colon cancer in patients as seen by the declining rates of colon cancer since screening has been implemented. Adenoma detection rate is an important quality measure that is affected by many factors, including withdrawal time. Limited research has evaluated whether prior history or interval time between colonoscopies affects withdrawal time. METHODS: Inclusion criteria: 872 patients at a tertiary academic center who underwent screening and surveillance colonoscopies. Exclusion criteria: patients with missing procedure timestamps, incomplete or aborted procedures, history of gastrointestinal malignancy, prior colon resection, genetic syndromes, or inflammatory bowel disease. For withdrawal time, log-transformation was applied to normalize the data. For the association of withdrawal time with history of prior colonoscopy analysis of variance was used. RESULTS: Overall, no significant difference was found in the withdrawal time in patients with or without a prior colonoscopy (12.42 vs. 11.66 minutes, P = 0.114). Subgroup analysis in the screening group did not show any difference (10.83 vs. 11.66 minutes, P = 0.668). In patients undergoing screening with prior colonoscopies, the withdrawal time was significantly decreased with increased colonoscopy interval, which was defined as the time from the prior colonoscopy to the current colonoscopy (range 1-357 months, P = 0.033). This was also seen with patients undergoing surveillance (range 1-194 months, P = 0.005). For patients undergoing surveillance, the withdrawal time for patients with interval of ≤ 3 years was significantly longer than that for the patients with interval >3 years (14.05 vs. 11.86 minutes, P = 0.036). Similar results were seen even after adjusting for polyp removal (12.05 vs. 10.99 minutes, P = 0.021). CONCLUSION: Increased interval between a patient’s prior colonoscopy is associated with a shorter withdrawal time. However, bias does not appear to exist on a patient’s initial screening colonoscopy. Reassurance from prior results may affect the endoscopist’s decision to withdraw more quickly. Large-scale or prospective studies should be done to validate these findings.

316 Colonoscopic Withdrawal Patterns in a Tertiary Academic Medical Center

INTRODUCTION: Withdrawal time is an important quality measure in colonoscopy as numerous studies have shown its effect on adenoma detection rate. Withdrawal during colonoscopy can be affected by many patient factors, but also individual endoscopist’s preferences and practices. We sought to characterize withdrawal patterns in our academic center for quality improvement purposes. METHODS: Inclusion criteria: 1,114 patients at a tertiary academic center who underwent screening and surveillance colonoscopies. Exclusion criteria: patients with missing procedure timestamps, incomplete or aborted procedures, history of gastrointestinal malignancy, prior colon resection, genetic syndromes, or inflammatory bowel disease. For cecal intubation time and withdrawal time, log-transformation was applied to normalize the data. Linear regression was used to assess the association of cecal intubation time with withdrawal time and adjusted for age, gender, and body mass index (BMI). The same analysis was performed by indication (screening and surveillance) and by endoscopist. RESULTS: After adjusting for age, gender, and BMI, increased cecal intubation time was associated with longer withdrawal time for all patients (n = 1144, P = 0.049). Subgroup analysis showed that this pattern held true for patients undergoing screening (n = 488, P = 0.033) but not surveillance (n = 656, P = 0.545). Further subgroup analysis excluding procedures that had polyps removed to control for time spent resecting polyps during withdrawal showed similar results (Table 1). When stratified by endoscopist, two of seven faculty members exhibited an association of longer cecal intubation time with increased withdrawal times. Increased withdrawal time was not associated with prior knowledge of positive family history of colon cancer (P = 0.729), nor personal history of cancer (P = 0.464). CONCLUSION: Longer cecal intubation times are associated with increased withdrawal times in our center particularly with screening colonoscopies, but variability appears to exist between faculty members. Bias against a patient’s family history of colon cancer or personal history of cancer does not appear to affect withdrawal time. Further studies including other academic centers should be done to validate these findings.

756 Novel Risk Factors and Outcomes in Inflammatory Bowel Disease Patients With Clostridium difficile Infection

INTRODUCTION: Patients with inflammatory bowel disease (IBD) are at significantly increased risk for Clostridium difficile infection (CDI). CDI in IBD is associated with increased in-hospital mortality, IBD treatment failure, re-hospitalization and high CDI recurrence rates. The existing literature on predictors of these adverse outcomes is limited. We evaluated four potentially modifiable novel risk factors (BMI, statin use, opioid use, and antidepressant use) on the risk and outcomes of CDI in patients with IBD. METHODS: CDI disease severity and other clinical outcomes, including colon surgery, CDI recurrence, CDI-related hospitalization, IBD exacerbations, and mortality were abstracted using the electronic medical record. Additionally, variables including BMI, statin use, opioid use, and antidepressant use at the time of CDI were abstracted from records for patients with IBD and CDI from 2008 and 2013. Statistical analysis comprised of descriptive statistics and univariate and multivariate logistic regression analyses. RESULTS: There were 137 patients with IBD and CDI included in this study: 70 with ulcerative colitis (51%), 63 with Crohn's disease (46%), and 4 with indeterminate colitis (3%). The median age was 46 years, and 55% were female. On multivariate analysis controlling for age, 43% of patients in the overweight BMI category had severe or severe complicated CDI, compared to 22% of patients in the underweight/normal BMI (OR, 2.85, P = 0.02) and 19% in the obese category (OR, 3.95, P = 0.04). Statin use was associated with severe or severe complicated CDI when controlling for age and BMI (OR, 5.66, P = 0.01). On multivariate analysis controlling for age and CDI severity, there was no association between statin use and post-CDI IBD exacerbations. Opioid and antidepressant use were not associated with CDI disease severity or IBD exacerbations. BMI category, statin use, opioid use, and antidepressant use were not associated with colon surgery, CDI recurrence, CDI-related hospitalizations, or mortality at 1 year. CONCLUSION: An overweight BMI and statin use were associated with severe or severe complicated CDI. There was no association between statin use and IBD exacerbations following CDI. Opioid and antidepressant use were not associated with disease severity or frequency of IBD exacerbations following CDI. Further studies are needed to better understand how these results could impact management of patients with IBD to improve clinical outcomes and potentially reduce the risk of CDI.

Malignant Perforation of Sigmoid Colon in Long-standing Ulcerative Colitis

Malignant Perforation of Sigmoid Colon in Long-standing Ulcerative Colitis

Changes in Oral Microbial Ecology of C57BL/6 Mice at Different Ages Associated with Sampling Methodology.

The mouth is an important niche for bacterial colonization. Previous research used mouth microbiota to predict diseases like colon cancer and inflammatory bowel disease (IBD). It is still unclear how the sampling methodology influences microbial characterization. Our aim was to determine if the sampling methods, e.g., cotton swab or tissue biopsy, and the age influence the oral microbial composition of mice. Microbial DNA was extracted using a commercial kit and characterized targeting the 16s rRNA gene from mouth swabs and tissue biopsies from 2 and 15 months old C57BL/6 male mice kept in the same SPF facility. Our results show statistical different microbial community of the different ages, type of sampling, and the two fixed factors age x type of sample (p-value < 0.05). At the genus level, we identified that the genera Actinobacillus, Neisseria, Staphylococcus, and Streptococcus either increase or decrease in abundance depending on sampling and age. Additionally, the abundance of Streptococcus danieliae, Moraxella osloensis, and some unclassified Streptococcus was affected by the sampling method. While swab and tissue biopsies both identified the common colonizers of oral microbiota, cotton swabbing is a low-cost and practical method, validating the use of the swab as the preferred oral sampling approach.

Association Between Indefinite Dysplasia and Advanced Neoplasia in Patients With Inflammatory Bowel Diseases Undergoing Surveillance

Background and aimsLittle is known about the clinical significance of indefinite dysplasia (IND) in patients with inflammatory bowel diseases (IBD) undergoing colonoscopic surveillance for colorectal neoplasia.MethodsWe conducted a retrospective cohort analysis of 492 patients with colonic IBD for 8 or more years or concomitant primary sclerosing cholangitis, with no history of advanced colorectal neoplasia (high-grade dysplasia or colorectal cancer) or colectomy, undergoing colorectal neoplasia surveillance at tertiary IBD referral center from 2001 through 2017. Subjects received consistent histopathologic grading of dysplasia. We collected data on time to development of (advanced) colorectal neoplasia or colectomy using Kaplan Meier methods. We identified factors independently associated with (advanced) colorectal neoplasia with multivariable Cox regression analysis.ResultsAfter 2149 person-years of follow-up, 53 patients (10.8%) received a diagnosis of IND without prior or synchronous low-grade dysplasia (LGD). Compared to patients without dysplasia, patients with IND had a significantly higher risk of advanced colorectal neoplasia (adjusted hazard ratio, 6.85; 95% CI, 1.78–26.4) and colorectal neoplasia (adjusted hazard ratio, 3.25; 95% CI, 1.50–7.05), but not colectomy (P=.78). Compared to IND, LGD was associated with a significantly higher risk of advanced colorectal neoplasia (P=.05). Following a diagnosis of no dysplasia, IND only, or LGD, the incidence rates of advanced colorectal neoplasia were 0.4% per patient-year, 3.1% per patient-year, and 8.4% per patient-year, respectively.ConclusionsIn a retrospective analysis of patients with IBD undergoing colorectal neoplasia surveillance with consistent histopathologic grading of dysplasia, IND was independently associated with a significant increase in risk of advanced colorectal neoplasia. These findings require validation and if confirmed, a reappraisal of the colorectal neoplasia surveillance guidelines.

Fbxw7 increases CCL2/7 in CX3CR1hi macrophages to promote intestinal inflammation.

Resident and inflammatory mononuclear phagocytes (MPh) with functional plasticity in the intestine are critically involved in the pathology of Inflammatory Bowel Diseases (IBD), in which the mechanism remains incompletely understood. In the present study, we found that increased expression of E3 ligase FBXW7 in the inflamed intestine was significantly correlated to IBD severity in both human diseases and mice model. Myeloid-Fbxw7 deficiency protected mice from dextran sodium sulfate (DSS) and 2,6,4-trinitrobenzene sulfonic acid (TNBS) induced colitis. Fbxw7 deficiency resulted in decreased production of chemokines CCL2 and CCL7 by colonic CX3CR1hi resident macrophages and reduced accumulation of CX3CR1int pro-inflammatory MPh in colitis colon tissue. Mice received AAV-shFbxw7 administration showed significantly improved survival rate and alleviated colitis. Mechanisms screening demonstrated that FBXW7 suppresses H3K27me3 modification and promotes Ccl2 and Ccl7 expression via degradation of histone-lysine N-methyltransferase EZH2 in macrophages. Taken together, our results indicate that FBXW7 degrades EZH2 and increases Ccl2/Ccl7 in CX3CR1hi macrophages, which promotes the recruiting CX3CR1int pro-inflammatory MPh into local colon tissues with colitis. Targeting FBXW7 might represent a potential therapeutic approach for intestine inflammation intervention.

Genetic Variations at rs3129891 and rs77005575 are Associated With Reduced Expression of Enteric α-defensins in IBD Patients.

Human enteric antimicrobial peptides composed predominantly of human enteric α-defensins (HD5 and HD6) are important in the mucosal antimicrobial barrier. Previous studies have identified that genetic variations at rs2066844, rs2066845, rs2066847 are associated with diminished enteric α-defensins in ileal Crohn's disease (CD). However, genetic variations associated with enteric antimicrobial peptides in colonic inflammatory bowel disease (IBD) remain unclear. To investigate it, we compared the colonic expression of antimicrobial peptides with respect to genotypes at 22 IBD-associated single-nucleotide polymorphisms (SNPs). In total, 16 controls and 102 colonic IBD patients including 42 ulcerative colitis (UC) and 60 CD were studies. Mutation assay was performed to determine their genotypes at 22 IBD-associated SNPs. Real-time PCR was performed to determine the colonic mRNA expression of HD5, HD6, lysozyme, and secretory phospholipase A2. Mutant genotypes at rs2066844, rs2066845, rs2066847 were not found, and only SNPs rs3129891 and rs77005575 were associated with enteric α-defensin expression in colonic IBD. In both inflamed and noninflamed tissues, colonic expression of HD5 and HD6 was significantly decreased in UC and CD patients carrying rs3129891 homozygous mutant genotype. And their colonic expression was significantly decreased in inflamed but not noninflamed tissues from UC patients carrying rs77005575 homozygous mutant genotype. However, both lysozyme and secretory phospholipase A2 in UC and CD were unaffected by rs3129891 and rs77005575 genotypes. As enteric α-defensins play critical roles in the mucosal antimicrobial barrier, their reduced expression may partly explain the microbial-induced mucosal inflammation in colonic IBD patients, especially in patients carrying rs3129891 and rs77005575 mutant genotypes.

Outcome of endoscopic resection of colonic polyps larger than 10 mm in patients with inflammatory bowel disease.

Background and study aims There are limited published data on endoscopic removal of colorectal polyps by endoscopic mucosal resection (EMR) and endoscopic mucosal dissection (ESD) in patients with inflammatory bowel disease (IBD). Patients and methods We performed a retrospective review of patients with colonic IBD and colonic polyps >10mm who underwent EMR and/or ESD at our institution between January 1, 2012 and June 31, 2016. Results Ninety-seven patients with pathology-confirmed IBD (median disease duration 16 years) were included. Mild or moderate active colitis (in background biopsies) was seen in 85 %. Of the total 124 polyps, location was ascending colon in 44 %, transverse in 15 % and sigmoid in 18.5 %; of the total, 55 % were < 20 mm and 45 % were ≥20mm in maximal diameter. Using the Paris classification, 56 % of polyps were polypoid sessile (Is) polyps, while 38 % were non-polypoid (IIa, IIb, IIc). EMR was used in 118 polyps, three required ESD, and three by combined EMR-ESD. Seventy-two percent were resected en-bloc; 28 % underwent piecemeal resection. Histology included low-grade dysplasia in 75, serrated adenoma in 31, and tubular adenoma in 14 polyps. Chromoendoscopy was used in 33 (26.6 %). Adverse events occurred in three patients. Colectomy was performed in 11 patients within 12 months. Recurrence was seen in 20 polyps, 11 of which were successfully resected en-bloc using EMR. Polyps ≥ 20 mm and polyps treated with APC were found to have a statistically significantly higher risk of recurrence. Conclusion This study demonstrates the efficacy and safety of endoscopic resection of large polyps in patients with IBD, making them effective alternatives to colectomy.