Partial normalization of pubertal timing in female mice with DSS colitis treated with anti-TNF-α antibody

Background

Inflammatory bowel disease (IBD) and resultant colitis occurring prior to puberty are frequently associated with delayed puberty and losses of growth and bone mineralization. Some of this delay may be due to colonic inflammation and associated systemic inflammation. To date no treatments for IBD have been shown to normalize the timing of puberty. Our objective in this study was to determine whether there is a normalization of the timing of puberty during treatment of colitis using monoclonal antibodies (abs) to tumor necrosis factor (TNF)-α.

Methods

We induced colitis in 23-day-old C57Bl6 female mice using 3% dextran sodium sulfate (DSS) for 7?days, followed by removal of DSS for an additional 3?days, resulting in 10?days of worsening colitis. DSS-treated mice received either TNF-α ab or Control ab on days 4 and 8 of colitis, while non-colitic Control mice received injections of TNF-α ab (Control?+?TNF-α ab). All groups were followed for the timing of vaginal opening until day of life 33, when they were euthanized for serum and colon collection.

Results

The DSS?+?TNF-α ab group had lower levels of systemic interleukin (IL)-6 and a partial normalization of the timing of vaginal opening compared to the DSS?+?Control ab group. There were no differences in weight gain, growth, or colon histological inflammatory scores between the DSS?+?TNFα ab and DSS?+?Control ab groups over the course of the experiment.

Conclusions

We conclude that anti-TNF-α ab treatment causes a partial normalization of pubertal timing coincident with decreased systemic inflammation in DSS colitis. These data may have implications regarding growth and bone mineralization outcomes in pediatric IBD.     

Grape Seed Extract Reduces the Severity of Selected Disease Markers in the Proximal Colon of Dextran Sulphate Sodium-Induced Colitis in Rats

Background

Grape seed extract (GSE) constitutes a rich source of procyanidins. GSE has been demonstrated to exert encouraging anti-inflammatory and anti-ulcer properties in experimental settings, although its effects on inflammation of the colon remain undefined.

Aim

To determine the effects of GSE in a rat model of dextran sulphate sodium (DSS) for ulcerative colitis.

Methods

Male Sprague–Dawley rats were gavaged daily (days 0–10) with GSE (400 mg/kg). Ulcerative colitis was induced by substituting DSS (2 % w/v) for drinking water from days 5–10. A sucrose breath test was performed on day 11 to determine small bowel function and intestinal tissues were collected for histological analyses. Statistical analysis was by one-way or repeated-measures ANOVA and p < 0.05 was considered significant.

Results

Compared to DSS-treated controls, GSE significantly decreased ileal villus height (14 %; p < 0.01) and mucosal thickness (13 %; p < 0.01) towards the values of normal controls. GSE reduced qualitative histological severity score (p < 0.05) in the proximal colon, although no significant effect was evident in the distal colon. However, GSE failed to prevent DSS-induced damage to the crypts of both colonic regions. Administration of GSE did not negatively impact metabolic parameters, nor did it induce any deleterious gastrointestinal side effects in healthy animals.

Conclusions

GSE decreased the severity of selected markers of DSS-induced colitis in the distal ileum and proximal colon, suggesting the potential as an adjuvant therapy for the treatment of ulcerative colitis. Future studies of GSE should investigate alternative delivery methods and treatment regimens, further seeking to identify the individual bioactive factors.     

Immunoregulatory function of PIR-A/B+ DCs in the inflammatory responses of dextran sodium sulfate-induced colitis

Background

Dendritic cells (DCs) may play an important role in forms of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis. DCs are generally recognized as initiators of acquired immunity and also serve as regulators of both innate and acquired immunity. We used the animal model of colitis induced by dextran sodium sulfate (DSS), and examined whether DCs prepared from the colon show immunoregulatory roles in the termination of DSS-induced colitis.

Methods

C57BL/6 mice exposed to DSS for 5 days developed acute colitis. DCs were isolated from the large intestinal lamina propria, and then analyzed for phenotypical, functional, and genetic data.

Results

Only PIR-A/B^low conventional DCs (cDCs) were detected in the steady state. However, after the treatment of DSS, PIR-A/B^high cDCs appeared and gradually increased from day 5 to day 7, at which time the DSS-induced colitis was terminated. Then, allogeneic mixed leukocyte reaction (MLR) was performed. The stimulatory activity of PIR-A/B^high cDCs obtained on day 7 was very low, and the addition of PIR-A/B^high cDCs suppressed the T cell proliferation in MLR, indicating the immunoregulatory role of PIR-A/B^high cDCs. The immunoregulatory role of PIR-A/B^high cDCs was confirmed by the in vivo transfer experiment, showing their therapeutic effect on DSS-induced colitis. The message level of TGFβi was significantly higher in PIR-A/B^high cDCs, while that of IFN-γ was highly upregulated in PIR-A/B^low cDCs, being well in accordance with the fact that PIR-A/B^high cDCs showed a suppressive function against activated T cells.

Conclusion

PIR-A/B^high cDCs showed a suppressive function against activated T cells by producing inhibitory cytokines.     

Increase in the Tight Junction Protein Claudin-1 in Intestinal Inflammation

Background and Aims

Studies have shown a decrease in key tight junction (TJ) proteins such as ZO-1 and occludin in both inflammatory bowel disease (IBD) and experimental models of inflammation. Our group has also shown an increase in claudin-1 in experimental colitis.

Methods

IEC-18 cells were treated with increasing doses of tumor necrosis factor alpha (TNF??). The TJ was assessed by transepithelial resistance (TER), permeability, Western blot, PCR, and immunofluorescence. Mucosal samples from patients with ulcerative colitis (UC), Crohn??s disease (CD), and without IBD (normal) were assayed for TJ proteins occludin and claudin-1 by Western blot and a ratio of claudin-1 to occludin (C:O) was calculated.

Results

IEC-18 cells had increased permeability, decreased TER and an increase in claudin-1 with TNF?? treatment. In human specimens, there was a decrease in occludin and an increase in claudin-1 leading to a significant increase in the C:O ratio in diseased UC colon compared to non-diseased UC colon (P < 0.001) and normal colon (P < 0.01). In CD, the C:O ratio was similar in all CD tissue irrespective of disease status.

Conclusions

Treatment of IEC-18 cells with TNF??, a key inflammatory cytokine in IBD, led to a significant increase in claudin-1 expression. There was a significant increase in the C:O ratio in diseased colon in UC compared to the healthy appearing UC colon and normal controls. The C:O ratio was unchanged in CD despite presence or abscence of gross disease. This suggests that there may be an underlying difference in the TJ between UC and CD.     

Assessment of anti-prothrombin antibodies in thrombosis complicating inflammatory bowel diseases

Purpose

In inflammatory bowel diseases (IBD), risk of thrombosis and production of antibodies are increased. In autoimmune and inflammatory disorders, a role of anti-prothrombin (aPT) antibodies in developing thrombosis has been hypothesised. The aim of the study is to evaluate the prevalence of aPT antibodies in IBD patients, with and without thrombosis.

Methods

Thirty-three IBD patients with thrombosis, 33 IBD patients without thrombosis matched for sex, age, diagnosis and disease activity and 66 sex- and age-matched healthy controls were enrolled. Thrombosis was considered recent when blood sample was obtained within 3 months from the event.

Results

Prevalence of aPT antibodies in thrombotic IBD patients (3/33, 9.1 %), non-thrombotic IBD patients (4/33, 12.1 %) and in healthy subjects (3/66, 4.5 %) did not result significantly different (p?=?0.377). The prevalence of aPT antibodies was more frequent in ulcerative colitis (6/32, 18.7 %) than in Crohn’s disease (1/34, 2.9 %) and healthy controls (p?=?0.022). Among thrombotic IBD patients, the prevalence of aPT antibodies was higher in those with recent (2/9, 22.2 %) than in those with previous thrombosis (1/24, 4.2 %) (p?=?0.103). All thrombotic IBD patients with aPT antibodies were affected by ulcerative colitis with previous history of deep venous thrombosis.

Conclusions

aPT antibodies do not appear to play a relevant role in thrombosis complicating IBD course. A possible association in ulcerative colitis patients with DVT could not be excluded.     

Claudin-2 Regulates Colorectal Inflammation via Myosin Light Chain Kinase-Dependent Signaling

Background

Claudins have been demonstrated to be associated with inflammatory bowel disease (IBD), but the specific role of claudin-2 in colorectal inflammation remains undefined.

Aims

We aimed to determine the role of claudin-2 in TNFα-induced colorectal inflammation.

Methods

We used claudin-2 (?/?) mice to assess the role of claudin-2 in colon. The mice were intraperitoneally injected with 3 μg of recombinant murine TNFα, and the NF-κB signaling and mRNA expression levels of proinflammatory cytokines and myosin light chain kinase (MLCK) were evaluated. Moreover, in claudin-2 (?/?) mice, colitis was induced by the administration of dextran sodium sulfate (DSS). The involvement of claudin-2 in colorectal inflammation was also investigated using the Caco-2 human colon adenocarcinoma cell line, and the expression of claudin-2 was downregulated using claudin-2 siRNA.

Results

TNFα-induced colorectal inflammation via NF-κB signaling activation was enhanced in claudin-2 (?/?) mice compared with that in claudin-2 (+/+) mice. MLCK expression level in the colon tissue of claudin-2 (?/?) mice treated with TNFα was enhanced in comparison to that of the claudin-2 (+/+) mice. DSS-induced colitis was more severe in the claudin-2 (?/?) mice than in the claudin-2 (+/?) mice. In in vitro experiments, the decreased expression of claudin-2 enhanced the expressions of IL-6, IL-1β and MLCK.

Conclusions

Our findings concerning the role of claudin-2 in epithelial inflammatory responses enrich our collective understanding of mucosal homeostasis and intestinal diseases such as IBD. Furthermore, the results of this study indicate that claudin-2 and MLCK are potential therapeutic targets for treatments against intestinal disease.     

A Role of the Aryl Hydrocarbon Receptor in Attenuation of Colitis

Background and Aims

The aryl hydrocarbon receptor (AhR), which is a member of the basic helix-loop-helix/Per-Arnt-Sim homology superfamily, plays an important role in multiple biological functions, and AhR knockout (AhR KO) animals suffer from a variety of organ disorders including a decline in the efficacy of their immune system. In addition, AhR activation is known to aid the maintenance of homeostasis in vivo. In this study, we investigated whether AhR is functionally associated with intestinal immunity.

Methods and Results

In in vivo experiments, it was found that dextran sodium sulfate (DSS)-evoked colitis was more severe in AhR KO mice than in C57BL/6J wild type mice. It was also revealed that the administration of DSS increased the expression levels of AhR and CYP1A1 mRNA in the colon epithelium. In addition, oral administration of ??-naphthoflavone (??NF), a non-toxic agonist of AhR, suppressed the pathogenesis of DSS-induced colitis. ??NF also attenuated DSS-induced colitis. In cell culture experiments, downregulation of AhR in human colon carcinoma SW480 cells enhanced the inflammatory responses evoked by lipopolysaccharide (LPS), and furthermore, AhR activation attenuated LPS-induced inflammatory responses, suggesting that AhR expressing intestinal epithelial cells are involved in the prevention of colitis.

Conclusions

Our findings about the potential role of AhR activators in epithelial immune regulation aid our understanding of mucosal homeostasis and inflammatory bowl disease (IBD) and suggest that AhR activation has therapeutic value for the treatment of IBD.     

Clinical characteristics of inflammatory bowel disease associated with primary sclerosing cholangitis

Purpose

Only a few studies have documented the characteristics of inflammatory bowel disease (IBD) associated with primary sclerosing cholangitis (PSC). We aimed to clarify the clinical and histopathological characteristics of IBD associated with PSC (PSC-IBD).

Methods

Twenty-nine patients with PSC and 60 patients with ulcerative colitis (UC) but without complicating PSC were enrolled in this study. First, the age and sex distribution, affected area, clinical course, number of recurrent attacks, and severity of UC were investigated. Then, mucosal specimens obtained from the right side (cecum and ascending colon), transverse colon, and the left side (descending colon, sigmoid colon, and rectum) during colonoscopy were studied for inflammatory cell infiltration, the presence of crypt abscesses, the degree of goblet cell disappearance, and edema.

Results

(1) The incidence of IBD in PSC patients was 68.9% (20/29). There were two peaks in the age distribution of PSC. Male PSC patients demonstrated a first peak and female patients a second peak. Male PSC-IBD patients were in their teens and 20s making the first peak. Female PSC-IBD patients were in their 50s and 60s making the second peak. The PSC-IBD patents were significantly younger than the patients without IBD (33.6 vs. 58.9?years, p?<?0.001). (2) PSC-IBD showed a right-sided predominance colonoscopically. (3) None of the patients had a severe clinical course, and a half of them were asymptomatic. (4) Histopathological examination demonstrated severe inflammatory cell infiltration in the cecum and ascending colon, whereas the degree was mild in the rectum/descending colon.

Conclusions

PSC-IBD shows characteristic clinical, colonoscopic, and histopathological findings.     

Lactulose Mediates Suppression of Dextran Sodium Sulfate-Induced Colon Inflammation by Increasing Hydrogen Production

Background

Molecular hydrogen (H₂) is a potent antioxidant and able to protect organs from oxidative stress injuries. Orally administered lactulose, a potent H₂ inducer, is digested by colon microflora and significantly increases H₂ production, indicating its potential anti-inflammatory action.

Objective

To evaluate the anti-inflammatory effects of lactulose on dextran sodium sulfate (DSS)-induced colitis in mice.

Methods

Mice were randomly assigned into seven groups, receiving regular distilled water, H₂-rich saline (peritoneal injection), DSS, oral lactulose (0.1, 0.15, 0.2 ml/10 g, respectively), and lactulose (0.2 ml/10 g) + oral antibiotics. The mouse model of human ulcerative colitis was established by supplying mice with water containing DSS. The H₂ breath test was used to determine the exhaled H₂ concentration. Body weight, colitis score, colon length, pathological features and tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), maleic dialdehyde (MDA) and marrow peroxidase (MPO) levels in colon lesions were evaluated.

Results

After 7 days, DSS-induced loss of body weight, increase of colitis score, shortening of colon length, pathological changes and elevated levels of TNF-α, IL-1β, MDA, and MPO in colon lesions, were significantly suppressed by oral lactulose administration and intraperitoneally injected H₂-rich saline. Ingestion of antibiotics significantly compromised the anti-inflammatory effects of lactulose. The H₂ breath test showed that lactulose administration significantly induced hydrogen production and that antibiotics administration could inhibit H₂ production.

Conclusion

Lactulose can prevent the development of DSS-induced colitis and alleviate oxidative stress in the colon, as measured by MDA and MPO, probably by increasing endogenous H₂ production.     

Characteristics and Treatment of Pyoderma Gangrenosum in Inflammatory Bowel Disease

Background

Pyoderma gangrenosum is a serious cutaneous complication seen in approximately 1 % of patients with inflammatory bowel disease (IBD). Oral corticosteroids are the mainstay treatment, although the evidence supporting their use is weak.

Aims

The purpose of this study was to investigate the characteristics of pyoderma gangrenosum associated with Crohn’s disease or ulcerative colitis and which treatments are prescribed in Spanish clinical practice.

Methods

In this retrospective, observational study, the medical records from all patients with IBD and a diagnosis of pyoderma gangrenosum attended by the gastroenterology departments of 12 Spanish hospitals were reviewed. Data on patient demographics and characteristics, underlying IBD and treatment, and pyoderma gangrenosum characteristics, treatment, and outcome were collected and analyzed.

Results

The data from 67 patients were analyzed (41 [61.2 %] women, 41 [61.2 %] with Crohn’s disease, 25 [37.3 %] with ulcerative colitis, and 1 [1.5 %] with indeterminate disease). The underlying disease was in remission in approximately one-third of patients at the time of presentation of pyoderma gangrenosum. Healing was achieved in all patients (in 3 without any systemic therapy). Oral corticosteroids were taken by 51 patients (76.1 %), almost always as first-line treatment, although definitive healing was attained in 19 (28.4 %). Biologic agents such as infliximab and adalimumab were taken by 31 patients (46.3 %) at some point (first-line in 6 patients [9.0 %]), with definitive healing in 29 patients (93.5 %).

Conclusions

Oral corticosteroid therapy remains the most common treatment for pyoderma gangrenosum associated with inflammatory bowel disease. Biologic therapies such as infliximab and adalimumab should also be considered.     

CMV Infection in Pediatric IBD

Purpose of Review

Patients with inflammatory bowel disease (IBD) are predisposed to infections. Cytomegalovirus (CMV) colitis in adult IBD patients, particularly ulcerative colitis (UC), is related to severe or steroid-refractory disease. The aim of this review is to summarize the data on the prevalence and role of CMV colitis in children with IBD.

Recent Findings

Data on CMV colitis in children continue to be very limited due to its rarity. As in adults, children with coexisting UC and CMV tend to have more severe colitis, are resistant to corticosteroids, and are at high risk for colectomies on short- and long-term follow-up.

Summary

In children, as in adults, the significance of CMV colitis, in terms of whether CMV is a pathogen that aggravates acute severe colitis or simply reflects disease severity, is still unknown.

     

The Phenotypic Expression of Inflammatory Bowel Disease in Patients with Primary Sclerosing Cholangitis Differs in the Distribution of Colitis

Background

Inflammatory bowel disease (IBD) associated with primary sclerosing cholangitis (PSC) is reported to be mild and prone to right-side predominance with rectal sparing. However, no dedicated studies evaluating patterns of presentation of liver disease with respect to IBD are available.

Methods

We performed a detailed histological examination of the colonic biopsies in the context of PSC, identifying 97 patients [89 with ulcerative colitis and ten with Crohn’s disease (CD)] stratified into two groups, based on their initial disease presentation: hepatic/biliary (group 1—PSC-IBD; n = 56) versus colonic (group 2—IBD-PSC; n = 41).

Results

Inflammatory bowel disease that preceded PSC had a tendency to have a “pan-colitis” distribution; this group included all patients with CD. Inflammatory bowel disease diagnosis that followed PSC presentation was more likely to be right-sided, sparing the descending, sigmoid and rectal regions (p = 0.002). In both groups, colitis was mild with focal deep plasmacytosis and occasional mild cryptitis. Active cryptitis with crypt abscesses, surface erosion and ulceration were not identified in any of the patients.

Conclusion

Colitis associated with PSC shows mild disease activity and the colitis pattern is associated with disease presentation, i.e. colitis preceding PSC (IBD-PSC cohort) typically have a pancolitic distribution, while colitis following PSC (PSC-IBD cohort) demonstrates right-sided predominance. Awareness by pathologists and clinicians of these patterns of inflammatory bowel disease is important and of use in directing appropriate investigations for patients.     

Prodromal Irritable Bowel Syndrome May Be Responsible for Delays in Diagnosis in Patients Presenting with Unrecognized Crohn��s Disease and Celiac Disease, but Not Ulcerative Colitis

Introduction

We aimed to determine the prevalence and duration of prodromal periods in patients with celiac disease and inflammatory bowel disease (Crohn??s disease and ulcerative colitis). Furthermore, we explored to what extent vague abdominal symptoms consistent with both disorders were attributed to irritable bowel syndrome (IBS) and if the presence of prodromal IBS (P-IBS) had an impact on prodrome duration.

Methods

In the study, 683 biopsy-proven patients (celiac n = 225, ulcerative colitis n = 228, Crohn??s disease n = 230) completed a postal survey including an assessment of prodromal periods and IBS symptoms during both the prodrome and at present (achieved by completion of the ROME II criteria). Results were compared to age/sex-matched controls (n = 348).

Results

Crohn??s disease patients had the highest prevalence of prodromes (94%) in comparison to ulcerative colitis (48%) and celiac disease (44%). However, Crohn??s disease patients have the lowest prevalence of P-IBS (29%) in comparison to ulcerative colitis (38%) and celiac disease (67%). Prodrome duration in patients with P-IBS Crohn??s disease was 4 years in comparison to 2 years without (p = 0.018). Prodrome duration in P-IBS celiac disease was 10 years in comparison to 7 years without (p = 0.046). Prodrome duration in patients with ulcerative colitis was not affected by P-IBS (p ?? 0.05). Age and sex were not confounding factors.

Conclusions

This is the first study to make direct comparisons of prodrome periods between celiac disease and IBD. Prodrome duration in celiac disease is significantly longer and more often characterized by P-IBS than IBD. In celiac disease and CD, P-IBS increases prodrome duration. This may represent a failure to understand the overlap between IBS and celiac disease/IBD.     

Variable Impact of CD39 in Experimental Murine Colitis

Background

Dysregulation of immune responses in inflammatory bowel diseases (IBD) results in intestinal inflammation and vascular injury while exacerbating systemic disease. CD39 is an ectonucleotidase, expressed by T regulatory cells and dendritic cells, that hydrolyzes extracellular nucleotides to modify those cellular immune responses implicated in IBD. Genetic polymorphisms of CD39 have been linked to Crohn??s disease while gene deletion in mice exacerbates dextran sodium sulphate-induced colitis.

Aim

The aim of this study was to test how global deletion of CD39 in mice impacts other models of experimental colitis.

Methods

Colitis was induced in CD39-null and -wt mice, using trinitrobenzene sulfonic acid (TNBS, 125 mg/kg) administered intrarectally. Oxazolone colitis (1.5% oxazolone in 50% alcohol) was induced in comparable groups. Morphology, clinical and molecular parameters, and FACS analyses of lamina propria mononuclear cells (LPMC) were examined in CD39-null mice. CD39 expression was analyzed in human IBD biopsies.

Results

Paradoxically, TNBS colitis in CD39-null mice was characterized by improved survival, favorable clinical scores, and decreased MPO activity, when compared to wt mice (P < 0.05). LPMC from TNBS colitis contained significantly increased amounts of T-cells (CD3⁺ and CD4⁺) and TNF-?? mRNA expression were increased over those in CD39 null mice (P < 0.05). In contrast, oxazolone treated CD39-null and wt mice had comparable outcomes. In both ulcerative colitis and Crohn??s disease, CD39 is present at high levels in intestinal tissue biopsies.

Conclusions

TNBS colitis was attenuated in CD39-null mice whereas oxazolone-induced colitis was not impacted. Impaired adaptive cellular immune reactivity in the CD39-null environment appears protective in hapten-mediated Th1-type colitis. CD39 is expressed at high levels in clinical IBD tissues.     

Neutrophil gelatinase-associated lipocalin (NGAL) in inflammatory bowel disease: association with pathophysiology of inflammation, established markers, and disease activity

Background

Neutrophil gelatinase-associated lipocalin (NGAL) is a multi-potent 25-kDa protein mainly secreted by neutrophils. In inflammatory bowel disease (IBD), overexpression of NGAL in colon epithelium has been previously shown. This is the first study analyzing serum and urinary NGAL levels in IBD patients, with regard to specific characteristics of patients and disease.

Methods

Serum and urinary NGAL levels were determined in 181 patients with IBD, 93 with ulcerative colitis (UC), and 88 with Crohn’s disease (CD), 82 healthy controls (HC), and 41 patients with irritable bowel syndrome (IBS).

Results

Serum NGAL levels were elevated in IBD patients (88.19?±?40.75?ng/mL) compared with either HC (60.06?±?24.18?ng/mL) or IBS patients (60.80?±?20.30?ng/mL), P?P?Conclusions Serum NGAL is elevated particularly in active IBD and correlates with established markers of inflammation and disease activity, implicating its role in the pathophysiology of IBD.     

Frequency of axial spondyloarthritis in Tunisian patients with inflammatory bowel diseases

Aim of the work

To determine the frequency, clinical and radiological features of axial spondyloarthritis in patients with inflammatory bowel diseases (IBD) and to characterize differences between patients with and without axial spondyloarthritis.