Terminal ileitis - When all factors come together.

A 45-year-old male, with a recent surgery for odontoid fracture, presented to the emergency department with a 15-days history of abdominal pain associated with fever and weight loss. He reported a recent history of antibiotic therapy due to respiratory infection and a frequent use of anti-inflammatory drugs (NSAIDs) in the last three months.

A quinazoline-based bromodomain inhibitor, CN210, ameliorates indomethacin-induced ileitis in mice by inhibiting inflammatory cytokine expression.

Inhibitors of bromodomain and extra-terminal motif (BET) proteins are emerging epigenetic therapeutics that suppress gene expressions that drive cancer and inflammation. The present study examined anti-inflammatory effects of a quinazoline-based BET inhibitor, CN210, in a murine ileitis model. CN210 was given orally 30 min before and 24 h after a subcutaneous administration of indomethacin. Macroscopic and histological evidences of ileitis, mucosal myeloperoxidase (MPO) activity and cytokine expressions were evaluated 48 h after the indomethacin administration. To further characterize the anti-inflammatory pathways modulated by CN210, its effects on RAW264 cells treated with lipopolysaccharide (LPS) were investigated. Competitive ligand binding and docking studies of CN210 to CREB-binding protein (CBP) and p300 were also performed. Oral administration of CN210 significantly reduced the severity of ileitis, normalized both proinflammatory MPO activity and concomitant cytokine expressions induced by indomethacin administration. Furthermore, CN210 attenuated the expression of cytokines and reversed the activation of nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPK) induced by LPS. Competitive ligand binding assays showed that CN210 bound to the bromodomains of two paralogous histone acetyltransferases, CBP and p300, in addition to the bromodomains of BET proteins. Docking studies of CN210 to the bromodomains of CBP and p300 showed a similarity to the binding mode of SGC-CBP30, a specific CBP/p300 inhibitor. CN210 ameliorates indomethacin-induced ileitis by inhibiting the expression of inflammatory cytokines through the attenuation of NF-κB and MAPK pathways. CN210 thus represents a new mode of therapy for non-steroidal anti-inflammatory drug-induced ileitis and inflammatory bowel disease.

Cryptogenic Multifocal Ulcerating Stenosing Enteropathy(CMUSE) and/or Chronic Non-specific Multiple Ulcers of the Small Intestine(CNSU) and Non-granulomatous Ulcerating Jejunoileitis (NGUJI).

PURPOSE OF REVIEW: The purpose is to make aware of the existence of the rare and exclusive small intestine (SI) diseases, namely cryptogenic multifocal ulcerating stenosing enteropathy (CMUSE) or chronic non-specific multiple ulcers of the small intestine (CNSU) and non-granulomatous ulcerating jejunoileitis (NGUJI). The article will elucidate their epidemiology, pathogenesis, clinical features, diagnosis, differentiating features and management. RECENT FINDINGS: Recent papers have published the clinical features and diagnostic criteria of CMUSE/CNSU and NGUJI. CNSU/CMUSE is caused by gene mutations involved in the prostaglandin pathways. Although capsule endoscopy can detect these lesions, it carries a risk of retention. TNF antagonists and azathioprine have shown response in few cases. CMUSE/CNSU and NGUJI are uncommon diseases that cause relapsing SI obstruction and bleed due to short-segment strictures and multiple shallow ulcers. This article focuses on current knowledge and novel insights regarding their pathogenesis, genetics, clinical features, diagnostic criteria and management. Multicentric clinical and genetic studies are the need of the hour.

Intravenous ustekinumab reinduction as a Crohn's disease rescue strategy following a secondary non-response.

Secondary non-response to biological treatments tends to occur in a high number of patients who undergo treatment with antiTNF, and it has also been observed in patients treated with vedolizumab or ustekinumab. The initial rescue guideline recommends intensifying the treatment by reducing the interval or increasing maintenance dosage. In the case of ustekinumab, the patients who began this treatment prior to its approval for treatment of Crohn's disease, were given a subcutaneous induction with no defined guideline and a maintenance dosage of 90 mg every eight weeks. Following secondary non-response in these patients, it was proposed that rescue be undertaken via intravenous reinduction adjusted for weight. We present a case of a patient with Crohn's disease with failure to respond to infliximab, adalimumab and vedolizumab who began treatment with ustekinumab prior to official approval. There was non-response at eight months but remission was achieved after reinduction with ustekinumab, adjusted for weight. This rescue guideline could be a cost-effective way to reinduce remission in this group of patients.

Inhibition of autotaxin alleviates inflammation and increases the expression of sodium-dependent glucose cotransporter 1 and Na+/H+ exchanger 3 in SAMP1/Fc mice.

Crohn's disease (CD) is a chronic, relapsing, inflammatory disease that is often associated with malnutrition because of inflammation in the small intestine. Autotaxin (ATX) is a secreted enzyme that produces extracellular lysophosphatidic acid. Increasing evidence suggests that ATX is upregulated during inflammation, and inhibition of ATX has been effective in attenuating chronic inflammatory conditions, such as arthritis and pulmonary fibrosis. This study aims to determine whether inhibition of ATX alleviates CD-associated inflammation and malnutrition by using SAMP1/Fc mice, a model of CD-like ileitis. SAMP1/Fc mice were treated the ATX inhibitor PF-8380 for 4 wk. Inhibition of ATX led to increased weight gain in SAMP1/Fc mice, decreased T helper 2 cytokine expression, including IL-4, IL-5, and IL-13, and attenuated immune cell migration. SAMP1/Fc mice have low expression of Na+-dependent glucose transporter 1 (SGLT1), suggesting impaired nutrient absorption associated with ileitis. PF-8380 treatment significantly enhanced SGLT1 expression in SAMP1/Fc mice, which could reflect the increased weight changes. However, IL-4 or IL-13 did not alter SGLT1 expression in Caco-2 cells, ruling out their direct effects on SGLT1 expression. Immunofluorescence analysis showed that the expression of sucrase-isomaltase, a marker for intestinal epithelial cell (IEC) differentiation, was decreased in inflamed regions of SAMP1/Fc mice, which was partially restored by PF-8380. Moreover, expression of Na+/H+ exchanger 3 was also improved by PF-8380, suggesting that suppression of inflammation by PF-8380 enhanced IEC differentiation. Our study therefore suggests that ATX is a potential target for treating intestinal inflammation and restoration of the absorptive function of the intestine. NEW & NOTEWORTHY This study is the first, to our knowledge, to determine whether autotoxin (ATX) inhibition improves inflammation and body weights in SAMP1/Fc mice, a mouse model of ileitis. ATX inhibition increased body weights of SAMP1/Fc mice and increased Na+-dependent glucose transporter 1 (SGLT1) expression. Increased SGLT1 expression in the inflamed regions was not a direct effect of cytokines but an indirect effect of increased epithelial cell differentiation upon ATX inhibition.

US Molecular Imaging of Acute Ileitis: Anti-Inflammatory Treatment Response Monitored with Targeted Microbubbles in a Preclinical Model.

Purpose To evaluate whether dual-selectin-targeted US molecular imaging allows longitudinal monitoring of anti-inflammatory treatment effects in an acute terminal ileitis model in swine. Materials and Methods The Institutional Animal Care and Use Committee approved all animal studies. Fourteen swine with chemically induced acute terminal ileitis (day 0) were randomized into the following groups: (a) an anti-inflammatory treatment group (n = 8; meloxicam, 0.25 mg per kilogram of body weight; prednisone, 0.5 mg/kg) and (b) a control group (n = 6; saline). US molecular imaging was performed with a clinical US machine after intravenous injection of clinically translatable dual P- and E-selectin-targeted microbubbles (5 × 108/kg). Three inflamed bowel segments per swine were imaged at baseline, as well as on days 1, 3, and 6 after treatment initiation. At day 6, bowel segments were analyzed ex vivo for selectin expression levels by using quantitative immunofluorescence. Results After induction of inflammation, US molecular imaging signal increased at day 1 in both animal groups (P < .001). At day 3, signal in the treatment group decreased (P < .001 vs day 1), while signal in control animals did not significantly change (P = .18 vs day 1) and was higher (P = .001) compared with that in the treatment group. At day 6, signal in the treatment group further decreased and remained lower (P = .02) compared with that in the control group. Immunofluorescence confirmed significant (P ≤ .04) downregulation of both P- and E-selectin expression levels in treated versus control bowel segments. Conclusion Dual-selectin-targeted US molecular imaging allows longitudinal monitoring of anti-inflammatory treatment effects in a large-animal model of acute ileitis. This supports further clinical development of this quantitative and radiation-free technique for monitoring inflammatory bowel disease. © RSNA, 2018 Online supplemental material is available for this article.

Secretion of biologically active pancreatitis-associated protein I (PAP) by genetically modified dairy Lactococcus lactis NZ9000 in the prevention of intestinal mucositis.

BACKGROUND: Mucositis is one of the most relevant gastrointestinal inflammatory conditions in humans, generated by the use of chemotherapy drugs, such as 5-fluoracil (5-FU). 5-FU-induced mucositis affects 80% of patients undergoing oncological treatment causing mucosal gut dysfunctions and great discomfort. As current therapy drugs presents limitations in alleviating mucositis symptoms, alternative strategies are being pursued. Recent studies have shown that the antimicrobial pancreatitis-associated protein (PAP) has a protective role in intestinal inflammatory processes. Indeed, it was demonstrated that a recombinant strain of Lactococcus lactis expressing human PAP (LL-PAP) could prevent and improve murine DNBS-induced colitis, an inflammatory bowel disease (IBD) that causes severe inflammation of the colon. Hence, in this study we sought to evaluate the protective effects of LL-PAP on 5-FU-induced experimental mucositis in BALB/c mice as a novel approach to treat the disease. RESULTS: Our results show that non-recombinant L. lactis NZ9000 have antagonistic activity, in vitro, against the enteroinvasive gastrointestinal pathogen L. monocytogenes and confirmed PAP inhibitory effect against Opportunistic E. faecalis. Moreover, L. lactis was able to prevent histological damage, reduce neutrophil and eosinophil infiltration and secretory Immunoglobulin-A in mice injected with 5-FU. Recombinant lactococci carrying antimicrobial PAP did not improve those markers of inflammation, although its expression was associated with villous architecture preservation and increased secretory granules density inside Paneth cells in response to 5-FU inflammation. CONCLUSIONS: We have demonstrated for the first time that L. lactis NZ9000 by itself, is able to prevent 5-FU-induced intestinal inflammation in BALB/c mice. Moreover, PAP delivered by recombinant L. lactis strain showed additional protective effects in mice epithelium, revealing to be a promising strategy to treat intestinal mucositis.

Local injection of dsRNA targeting calcitonin receptor-like receptor (CLR) ameliorates Clostridium difficile toxin A-induced ileitis.

Enteritis caused by Clostridium difficile toxin (Tx) is a nosocomial disease of increasing clinical concern, but the local mediators of C. difficile TxA inflammation are unknown. The potent vasodilator calcitonin gene-related peptide mediates neurogenic inflammation via the calcitonin receptor-like receptor (CLR). Here we examined the ileum-specific effects of reducing CLR on TxA ileitis by local preinjection of double-stranded RNAs. Treatment with CLR dsRNA for 7 d decreased CLR immunoreactivity, whereas treatment with non-CLR dsRNA did not. Subsequent injection of TxA in the same location increased CLR in rats treated with non-CLR dsRNA but not in rats treated with CLR dsRNA, documenting that local injection of dsRNA is effective in preventing the increase in CLR immunoreactivity in response to local TxA. After non-CLR dsRNA pretreatment, TxA induced robust intestinal secretion, myeloperoxidase activity, and histopathologic indications of inflammation including epithelial damage, congestion, neutrophil infiltration, loss of mucin from goblet cells, and increase in mast cell numbers. After CLR dsRNA pretreatment, TxA-induced changes in intestinal secretion and histopathologic inflammation were improved, including normal mucin staining and fewer resident mast cells. Loss of CLR prevented TxA-mediated activation of NF-κB and concomitant increases in pERK1/2 and TNF-α mRNA. Locally produced CLR plays a proinflammatory role in TxA ileitis via MAPK signaling and TNF-α. The results reported here strongly suggest that a local injection of dsRNA targeting CLR could be an effective local therapeutic approach at the inflammation site in the treatment of a growing, clinically relevant hospital-acquired disease, C. difficile infection.

In vivo inhibition of RIPK2 kinase alleviates inflammatory disease.

The RIPK2 kinase transduces signaling downstream of the intracellular peptidoglycan sensors NOD1 and NOD2 to promote a productive inflammatory response. However, excessive NOD2 signaling has been associated with numerous diseases, including inflammatory bowel disease (IBD), sarcoidosis and inflammatory arthritis, making pharmacologic inhibition of RIPK2 an appealing strategy. In this work, we report the generation, identification, and evaluation of novel RIPK2 specific inhibitors. These compounds potently inhibit the RIPK2 tyrosine kinase activity in in vitro biochemical assays and cellular assays, as well as effectively reduce RIPK2-mediated effects in an in vivo peritonitis model. In conjunction with the development of these inhibitors, we have also defined a panel of genes whose expression is regulated by RIPK2 kinase activity. Such RIPK2 activation markers may serve as a useful tool for predicting settings likely to benefit from RIPK2 inhibition. Using these markers and the FDA-approved RIPK2 inhibitor Gefitinib, we show that pharmacologic RIPK2 inhibition drastically improves disease in a spontaneous model of Crohn Disease-like ileitis. Furthermore, using novel RIPK2-specific inhibitors, we show that cellular recruitment is inhibited in an in vivo peritonitis model. Altogether, the data presented in this work provides a strong rationale for further development and optimization of RIPK2-targeted pharmaceuticals and diagnostics.

Toll-like receptor (TLR) 2 agonists ameliorate indomethacin-induced murine ileitis by suppressing the TLR4 signaling.

BACKGROUND AND AIM: Few drugs have been found satisfactory in the treatment of nonsteroidal anti-inflammatory drugs (NSAIDs)-induced enteropathy. Toll-like receptor (TLR) 4 and aberrant leukocyte migration to the intestinal mucosa are reported to be involved in the pathology of intestinal enteropathy and TLR2 agonists have been found to evoke hyposensitivity to TLR4 stimulation in vitro. In this study, we investigated whether and how lipoarabinomannan (LAM) or lipoteichoic acid (LTA), TLR2 agonists, attenuated indomethacin (IND)-induced intestinal damage. METHODS: LAM (0.5 mg/kg) or LTA (15 mg/kg) was administered intraperitoneally to mice before IND (10 mg/kg) administration. Disease activity was evaluated macroscopically and histologically. In the migration analysis, fluorescence-labeled leukocyte movement in the intestinal microvessels was observed by intravital microscopy. Expression of P-selectin, MAdCAM-1, TLR2, TLR4, and F4/80 was observed immunohistochemically. In the in vitro analysis, RAW264.7 macrophage cells were preincubated with LAM and stimulated with lipopolysaccharide (LPS), and the mRNA expression levels of TLR4, tumor necrosis factor-α, and interleukin-12p40 were measured. RESULTS: Pretreatment with LAM or LTA significantly decreased IND-induced injury as well as decreased leukocyte infiltration. Pretreatment with LAM decreased IND-induced TLR4 expression on F4/80(+) macrophages, the level of P-selectin expression, and leukocyte migration in the small intestinal vessels. In the in vitro study, a single administration of LAM decreased TLR4 mRNA expression and inhibited the increase in mRNA expression of inflammatory cytokines by LPS in a dose-dependent manner. CONCLUSION: TLR2 agonists attenuated IND-induced small intestinal lesions and leukocyte infiltration probably by suppressing the TLR4 signaling pathway in tissue macrophages.

[Experimental substantiation of possibility of sanation for purulent enteritis in mechanical acute ileus].

In experiment on the model of mechanical acute ileus (AI) in accordance to morphological and microbiological investigations data there was established, that in intestinal wall, situated above the obstacle place, purulent enteritis occurs, what may constitute the origin of purulent-septic complications after elimination of the Al cause. Application of antibacterial preparations permits to slow down the progression of destructive processes in the affected intestinal wall.

Anti-Inflammatory Effect of Dietary Pentadecanoic Fatty Acid Supplementation on Inflammatory Bowel Disease in SAMP1/YitFc Mice.

BACKGROUND/OBJECTIVES: Dietary fats have been linked to the increasing incidence of chronic diseases, including inflammatory bowel diseases (IBD), namely, Crohn's disease (CD). METHODS: This study investigated the impact of pentadecanoic acid (C15:0), a type of an odd-numbered chain saturated fatty acid, for its potential anti-inflammatory properties in different mouse models of experimental IBD using the SAMP1/YitFc (SAMP) mouse line (14- or 24-week-old), including chronic ileitis and DSS-induced colitis. To quantitively assess the effect of C:15, we tested two dosages of C:15 in selected experiments in comparison to control mice. Intestinal inflammation and intestinal permeability were used as primary outcomes. RESULTS: In ileitis, C:15 supplementation showed an anti-inflammatory effect in SAMP mice (e.g., a reduction in ileitis severity vs. control p < 0.0043), which was reproducible when mice were tested in the DSS model of colitis (e.g., reduced permeability vs. control p < 0.0006). Of relevance, even the short-term C:15 therapy prevented colitis in mice by maintaining body weight, decreasing inflammation, preserving gut integrity, and alleviating colitis signs. CONCLUSIONS: Collectively, the findings from both ileitis and colitis in SAMP mice indicate that C:15 may have therapeutic effects in the treatment of IBD (colitis in the short term). This promising effect has major translational potential for the alleviation of IBD in humans.

Flt3 ligand expands CD103⁺ dendritic cells and FoxP3⁺ T regulatory cells, and attenuates Crohn's-like murine ileitis.

UNLABELLED: BACKGROUND; Imprinting an effector or regulatory phenotype on naïve T cells requires education at induction sites by dendritic cells (DC). Objectives To analyse the effect of inflammation on the frequency of mononuclear phagocytes (MP) and the effect of altering their frequency by administration of Flt3-L in chronic ileitis. METHODS: Using a tumour necrosis factor (TNF) driven model of ileitis (ie, TNFΔARE) that recapitulates many features of Crohn's disease (CD), dynamic changes in the frequency and functional state of MP within the inflamed ileum were assessed by flow cytometry, immunofluorescence and real-time reverse-transcription PCR and by generating CX(3)CR1 GFP-reporter TNFΔARE mice. The effect of Flt3-L supplementation on the severity of ileitis, and the frequency of CD103(+) DC and of FoxP3(+) regulatory T cells was also studied in TNFΔARE mice. RESULTS: CD11c(Hi)/MHCII(+) MP accumulated in inflamed ilea, predominantly mediated by expansion of the CX(3)CR1(+) MP subpopulation. This coincided with a decreased pro-regulatory CD103(+) DC. The phenotype of these MP was that of activated cells, as they expressed increased CD80 and CD86 on their surface. Flt3-ligand administration resulted in a preferential expansion of CD103(+) DC that attenuated the severity of ileitis in 20-week-old TNFΔARE mice, mediated by increased CD4(+)/CD25(+)/FoxP3(+) regulatory T cells. CONCLUSIONS: Results support a role for Flt3-L as a potential therapeutic agent in Crohn's-like ileitis.

Capecitabine-Induced Ileitis during Neoadjuvant Pelvic Radio-Chemotherapy for Locally Advanced Rectal Cancer: A Case Report with Literature Review.

We report on a clinical case of capecitabine-induced acute ileitis in a patient treated with pre-operative concurrent chemoradiation with capecitabine for locally advanced rectal cancer and provide a comprehensive literature review. This a rare, but life-threatening, clinical situation, that clinicians should be aware of. Severe persistent diarrhea is the most frequent clinical feature and computed tomography is a valid tool for diagnosis. Conservative management includes capecitabine withdrawal, antidiarrheal therapy and endovenous hydration, together with dietary modifications and broad-spectrum antibiotics. Pelvic irradiation represents an adjunctive risk factor, which may increase the likelihood of occurrence of terminal ileitis. Early recognition and prompt intervention are crucial for successful clinical management.

Critical role of endothelial P-selectin glycoprotein ligand 1 in chronic murine ileitis.

L-selectin ligands might be relevant for inflammatory cell trafficking into the small intestine in a spontaneous model of chronic ileitis (i.e., SAMP1/YitFc mice). Immunoblockade of peripheral node addressin or mucosal addressin cell adhesion molecule 1 failed to ameliorate ileitis, whereas P-selectin glycoprotein ligand 1 (PSGL-1) neutralization attenuated both the adoptively transferred and spontaneous disease. PSGL-1 was detected in venules of mesenteric lymph node and small intestine by immunohistochemistry and confirmed by real-time reverse transcription polymerase chain reaction and flow cytometry. In addition, reconstitution of wild-type mice with PSGL-1(-/-) bone marrow demonstrated that PSGL-1 messenger RNA and PSGL-1 protein expression remained on endothelium, localized within mesenteric lymph node and small intestine. Endothelial PSGL-1 bound P-selectin-IgG and its blockade or genetic deletion altered the recruitment of lymphocytes to the small intestine, as revealed by intravital microscopy and homing studies. Endothelial expression of PSGL-1 adds a new dimension to the various cellular interactions involved in small intestinal recruitment. Thus, the multiple roles of PSGL-1 may explain why targeting this single adhesion molecule results in attenuation of chronic murine ileitis, a disease previously resistant to antiadhesion molecule strategies.

Retinoic acid attenuates ileitis by restoring the balance between T-helper 17 and T regulatory cells.

BACKGROUND & AIMS: Retinoic acid (RA), produced by intestinal epithelial cells (IECs) and dendritic cells (DCs) promotes the induction of regulatory T cells (Tregs) and decreases the induction of T-helper (Th)17 cells. METHODS: We studied the roles of RA in mice that overproduce tumor necrosis factor (TNF) and develop chronic ileitis (TNF_ARE mice). We assessed the frequency and function of CD103+ DCs, Th17 cells, and Tregs by flow cytometry, and we measured expression of cytokines and retinaldehyde dehydrogenase (RALDH) enzymes in ileum samples, DCs, and IECs by real-time polymerase chain reaction. We quantified RA by electrochemical analysis and examined the effect of RA supplementation on TNF-induced ileitis using histologic, coculture, and suppression assays and flow cytometry. RESULTS: Numbers of CD103+ DCs decreased in the inflamed ilea of mice with chronic disease; RA synthetic machinery (RALDH1,2) was down-regulated. Nevertheless, the proportion of CD4+, CD25+, FoxP3+ Tregs increased, indicating an alternate source for RA. IECs responded to reduced levels of RA by up-regulating RALDH3 in vivo and in vitro. Net tissue levels of RA remained lower in TNF+ARE than wild-type mice, indicating that epithelial up-regulation of RALDH3 could not maintain adequate concentrations of RA, probably because of loss of IEC mass. RA supplementation significantly attenuated disease by increasing the number and function of CD103+ DCs and Tregs and reducing Th17 cells. CONCLUSIONS: Reduced levels of RA appear to induce IECs to up-regulate synthesis of RA. RA supplementation attenuates ileitis through its effects on CD103+ DCs, Tregs, and Th17 cells. RA supplementation might offer therapeutic benefit in Crohn's disease.