Medical therapy for ulcerative colitis 2004

Multiomics-empowered Deep Phenotyping of Ulcerative Colitis Identifies Biomarker Signatures Reporting Functional Remission States

INTRODUCTION

Ulcerative colitis [UC] is a chronic disease with rising incidence and unclear aetiology. Deep molecular phenotyping by multiomics analyses may provide novel insights into disease processes and characteristic features of remission states.

METHODS

UC pathomechanisms were assessed by proteome profiling of human tissue specimens, obtained from five distinct colon locations for each of the 12 patients included in the study. Systemic disease-associated alterations were evaluated thanks to a cross-sectional setting of mass spectrometry-based multiomics analyses comprising proteins, metabolites, and eicosanoids of plasma obtained from UC patients during acute episodes and upon remission, in comparison with healthy controls.

RESULTS

Tissue proteome profiling indicated colitis-associated activation of neutrophils, macrophages, B and T cells, fibroblasts, endothelial cells and platelets, and hypoxic stress, and suggested a general downregulation of mitochondrial proteins accompanying the establishment of apparent wound healing-promoting activities including scar formation. Whereas pro-inflammatory proteins were apparently upregulated by immune cells, the colitis-associated epithelial cells, fibroblasts, endothelial cells, and platelets seemed to predominantly contribute anti-inflammatory and wound healing-promoting proteins. Blood plasma proteomics indicated chronic inflammation and platelet activation, whereas plasma metabolomics identified disease-associated deregulations of gut and gut microbiome-derived metabolites. Upon remission several, but not all, molecular candidate biomarker levels recovered back to normal.

CONCLUSION

The findings may indicate that microvascular damage and platelet deregulation hardly resolve upon remission, but apparently persist as disease-associated molecular signatures. This study presents local and systemic molecular alterations integrated in a model for UC pathomechanisms, potentially supporting the assessment of disease and remission states in UC patients.

Treatment of colitis by oral negatively charged nanostructured curcumin in rats

PURPOSE

To examine the effects of a negatively charged nanostructured curcumin microemulsion in experimental ulcerative colitis (UC) in rats.

METHODS

Four percent acetic acid was used to induce UC. The animals were treated for seven days and randomly assigned to four groups: normal control (NC), colitis/normal saline (COL/NS), colitis/curcumin (COL/CUR), and colitis/mesalazine (COL/MES). The nanostructured curcumin was formulated with a negative zeta potential (-16.70 ± 1.66 mV). Dosage of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin 1-β (IL-1β), interleukin 6 (IL-6), and antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase), macro and microscopic evaluation of the colon tissue were analyzed.

RESULTS

The COL/CUR group had a higher level of antioxidant enzymes compared to the COL/MESgroup. The levels of TNF-α, IL-1β and IL-6 were significantly lower in the colonic tissue of the COL/CUR group rats, when compared to the COL/NS and COL/MES groups (p < 0.001). The presence of ulcers in the colonic mucosa in rats of the COL/NSgroup was significantly higher than in the COL/MES group (p < 0.001). In the NC and COL/CUR groups, there were no ulcers in the colonic mucosa.

CONCLUSIONS

The nanostructured microemulsion of curcumin, used orally, positively influenced the results of the treatment of UC in rats. The data also suggests that nanostructured curcumin with negative zeta potential is a promising phytopharmaceutical oral delivery system for UC therapy. Further research needs to be done to better understand the mechanisms of the negatively charged nanostructured curcumin microemulsion in UC therapy.

Efficacy and safety of adjuvant curcumin therapy in ulcerative colitis: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumin, an active polyphenol extracted from Traditional Chinese medicine Curcuma longa (turmeric), has shown many health-related benefits and pharmacological effects. Adjuvant curcumin therapy for ulcerative colitis has become increasingly popular, but its efficacy and safety of which is still controversial. The purpose of this study is to evaluate the efficacy and safety of adjuvant curcumin therapy in ulcerative colitis.

MATERIALS AND METHODS

The Medline, EMBASE, the Cochrane Library, CNKI, VIP, WanFang, and SinoMed databases were searched from inception to June 2021, to identify all randomized controlled clinical trials with adjuvant curcumin therapy in ulcerative colitis. The primary outcomes were clinical and endoscopic remission, and subgroup analyses were also performed.

RESULTS

Six randomized trials with a total of 385 participants were included in this study. Qualified trials recommended that adjuvant curcumin therapy for ulcerative colitis was effective in inducing clinical remission (RR = 2.10, 95% CI 1.13 to 3.89), but not in clinical improvement (RR = 1.62, 95% CI 1.00 to 2.61), endoscopic remission (RR = 4.17, 95% CI 0.63 to 27.71) or endoscopic improvement (RR = 4.13, 95% CI 0.20 to 87.07). Included studies showed that appropriate dosage, formation, longer duration, and topical medication may have a greater potential advantage. No severe adverse effects had been reported.

CONCLUSIONS

Available evidence suggested that adjuvant curcumin therapy may be effective for clinical remission in ulcerative colitis patients without causing severe adverse effects. The appropriate methods of administration can achieve better curative effect, which requires further study to verify.

Induction of mucosal healing by intensive granulocyte/monocyte adsorptive apheresis (GMA) without use of corticosteroids in patients with ulcerative colitis: long-term remission maintenance after induction by GMA and efficacy of GMA re-treatment upon relapse

This study examined the long-term maintenance rate after inducing remission by intensive granulocyte/monocyte adsorptive apheresis (GMA) without use of corticosteroids (CS) and GMA re-treatment efficacy in the same patients upon relapse with ulcerative colitis. Patients who achieved clinical remission and mucosal healing (MH) by first-time intensive GMA (first GMA) without CS were enrolled. The cumulative non-relapse survival rate up to week 156 was calculated. Patients with relapse during the maintenance period underwent second-time intensive GMA (second GMA) without CS. Clinical remission and MH rates following second GMA were compared to those following first GMA in the same patients. Of the 84 patients enrolled, 78 were followed until week 156 and 34 demonstrated relapse. The cumulative non-relapse survival rate by week 156 was 56.4%. Clinical remission and MH rates after second GMA did not differ from those after first GMA in the same patients (week 6: clinical remission, 100% vs 88.4%, p = 0.134; MH, 100% vs 84.8%, p = 0.074). In conclusion, MH induction by intensive GMA without use of CS in ulcerative colitis patients contributes to subsequent long-term clinical remission maintenance. GMA re-treatment efficacy was comparable to that of first GMA in the same patients who had relapse.

Oral Nanoparticles of SNX10-shRNA Plasmids Ameliorate Mouse Colitis

Background

Our previous study found that deletion of Sorting nexin 10 (SNX10) can protect against colonic inflammation and pathological damage induced by dextran sulfate sodium (DSS). This inspired us that modulation of SNX10 expression in colonic epithelial cells might represent a promising therapeutic strategy for inflammatory bowel disease (IBD).

Methods

Effective delivery of siRNA/shRNA to silence genes is a highly sought-after means in the treatment of multiple diseases. Here, we encapsulated SNX10-shRNA plasmids (SRP) with polylactide-polyglycolide (PLGA) to make oral nanoparticles (NPs), and then applied them to acute and chronic IBD mice model, respectively. The characteristics of the nanoparticles were assayed and the effects of SRP-NPs on mouse IBD were evaluated.

Results

High-efficiency SNX10-shRNA plasmids were successfully constructed and coated with PLGA to obtain nanoparticles, with a particle size of 275.2 ± 11.4mm, uniform PDI distribution, entrapment efficiency of 87.6 ± 2.5%, and drug loading of 13.11 ± 1.38%, displayed dominant efficiency of SNX10 RNA interference in the colon. In both acute and chronic IBD models, SRP-NPs could effectively reduce the loss of mice body weight, relieve the intestinal mucosal damage and inflammatory infiltration, inhibit the expression of inflammatory cytokines IL-1β, IL-23, TNF-α, and down-regulate the expression of toll-like receptors (TLRs) 2 and 4.

Conclusion

Oral nanoparticles of SNX10-shRNA plasmid displayed dominant efficiency of SNX10 RNA interference in the colon and ameliorate mouse colitis via TLR signaling pathway. SNX10 is a new target for IBD treatment and nanoparticles of SNX10-shRNA plasmid might be a promising treatment option for IBD.

Efficacy and safety of adsorptive granulomonocytapheresis in Chinese patients with ulcerative colitis: A retrospective analysis of 50 cases with focus on factors impacting clinical efficacy

Background

Myeloid‐derived leucocytes, a major source of inflammatory cytokines, play an important role in the exacerbation of ulcerative colitis (UC). Selective depletion of myeloid leucocytes by adsorptive granulomonocytapheresis (GMA) with an Adacolumn should alleviate inflammation and promote remission. However, there are discrepancies among the reported efficacy outcomes. This study aimed to evaluate the efficacy and safety of GMA in UC patients with a focus on factors affecting clinical efficacy.

Methods

This was a retrospective analysis of 50 patients with active UC who had received GMA therapy. GMA efficacy was evaluated based on the Rachmilewitz's clinical activity index (CAI) and Mayo endoscopic score for mucosal healing. Laboratory findings were analyzed to demonstrate any relationship with the GMA‐responder or nonresponder feature. Adverse events were recorded during and after GMA therapy.

Results

The overall clinical remission rate (CAI ≤4) was 79.2%, and among these, the mucosal healing rate was 59.2%. The clinical remission rate was 69.2% in patients who received 5 GMA sessions and 82.3% in patients who received 10 sessions. Significantly higher baseline CAIs and lower albumin and hemoglobin levels were observed in nonremission cases compared with those who achieved remission. Four patients (8%) experienced transient adverse events, but none were severe.

Conclusions

GMA was favored by patients because of its safety and nonpharmacological treatment options. Accordingly, UC patients were spared from pharmaceuticals after applying GMA therapy.

Efficacy of adjuvant curcumin therapy in ulcerative colitis: A meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Aminosalicylic acids are recognized to be the first-line treatment options for ulcerative colitis. Currently, the effectiveness of curcumin as an adjuvant treatment in ulcerative colitis has been investigated, which was still controversial. This study aimed to systematically review and meta-analyze the efficacy and safety of curcumin as an adjuvant treatment in ulcerative colitis.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched from original to July 2019, and relevant randomized controlled clinical trials were enrolled and analyzed. The primary outcomes were clinical and endoscopic remission; meanwhile, the secondary outcomes were clinical and endoscopic improvement. Subgroup analyses of doses, delivery way, form, and intervention time of curcumin were also conducted.

RESULTS

Six randomized controlled clinical trials with a total of 349 patients were included. Eligible trials suggested that adjuvant curcumin treatment in ulcerative colitis was effective in inducing clinical remission (odds ratio [OR] = 5.18, 95% confidence interval [CI]: 1.84-14.56, P = 0.002), endoscopic remission (OR = 5.69, 95% CI: 1.28-25.27, P = 0.02), and endoscopic improvement (OR = 17.05, 95% CI: 1.30-233.00, P = 0.03), but not in clinical improvement (OR = 4.79, 95% CI: 1.02-22.43, P = 0.05). We can see the potential advantages in large dosage, topical enema, special drug form, and longer duration from the enrolled studies. There were no severe side effects reported.

CONCLUSIONS

Curcumin, as an adjuvant treatment of mesalamine, was proved to be effective and safe in ulcerative colitis. Better efficacy can be achieved with suitable dose, delivery way, formation, and intervention time, which needs further study to verify.

Orally Deliverable Nanotherapeutics for the Synergistic Treatment of Colitis-Associated Colorectal Cancer

Purpose: Colitis-associated colorectal cancer (CAC) poses substantial challenges for effective treatment. Currently, there is a considerable need for the development of orally bioavailable dosage forms that enable the safe and effective delivery of therapeutic drugs to local diseased lesions in the gastrointestinal tract. Experimental Design: In this study, we developed orally deliverable nanotherapeutics for the synergistic treatment of inflammatory bowel diseases (IBDs) and CAC. Water-insoluble curcumin (CUR) and 7-ethyl-10-hydroxycamptothecin (SN38), which served as anti-inflammatory and cytotoxic agents, respectively, were chemically engineered into hydrophilic mucoadhesive chitosan for the generation of chitosan-drug amphiphiles. Results: The resulting amphiphilic constructs formed core-shell nanostructures in aqueous solutions and were orally administered for in vivo therapeutic studies. Using a preclinical CAC mouse model, we showed that the orally delivered nanotherapeutics locally accumulated in inflamed intestinal regions and tumor tissues. Furthermore, the therapeutic synergy of the combined nanotherapeutics in CAC mice was evaluated. Compared with their individual drug forms, combined CUR and SN38 nanoparticles yielded synergistic effects to alleviate intestinal inflammation and protect mice from ulcerative colitis. Notably, the combinatorial therapy demonstrated a remarkable tumor shrinkage with only ~6% of the total tumors exceeding 4 mm in diameter, whereas ~35% of tumors were observed to exceed a diameter of 4 mm in the saline-treated CAC mice. These data suggest a new and reliable approach for improving the treatment of IBD and CAC. Conclusions: Our results showed that bioadhesive chitosan materials can be used to produce colloidal-stable nanotherapeutics that are suitable for oral delivery. Both nanotherapeutics exhibited substantial accumulation in inflamed intestinal regions and tumor tissues and showed good synergy for treating CAC, warranting further clinical translation.

A Proresolving Peptide Nanotherapy for Site-Specific Treatment of Inflammatory Bowel Disease by Regulating Proinflammatory Microenvironment and Gut Microbiota

The incidence and prevalence of inflammatory bowel disease (IBD) increases steadily worldwide. There is an urgent need for effective and safe IBD therapies. Accelerated resolution of inflammation is a new strategy for the management of inflammatory diseases. For effective and safe IBD treatment, herein a smart nanotherapy (i.e. oxidation-responsive nanoparticles containing a proresolving annexin A1-mimetic peptide Ac2-26, defined as AON) is developed, which can release packaged Ac2-26, in response to highly expressed reactive oxygen species (ROS) at diseased sites. AON effectively protects Ac2-26 from degradation in the enzyme-rich environment of the gastrointestinal tract. By delivering this nanotherapy to the inflamed colons of mice with IBD, site-specific release and accumulation of Ac2-26 in response to high levels of ROS at the inflammatory sites are achieved. Mechanistically, the Ac2-26-containing, oxidation-labile nanotherapy AON effectively decreases the expression of proinflammatory mediators, attenuates trafficking and infiltration of inflammatory cells, promotes efferocytosis of apoptotic neutrophils, and increases phenotypic switching of macrophages. Therapeutically, AON reduces symptoms of inflammation, accelerates intestinal mucosal wound healing, reshapes the gut microbiota composition, and increases short-chain fatty acid production. Additionally, oral delivery of this nanomedicine shows excellent safety profile in a mouse model, conferring the confidence for further development of a targeted precision therapy for IBD and other inflammatory diseases.

Serum interleukin-6 level is associated with response to infliximab in ulcerative colitis

OBJECTIVES

Infliximab is effective in patients with ulcerative colitis (UC); however, one-third of patients do not respond and require additional therapies such as other biologic agents. Therefore, the aim of this study was to analyze the association between pro-inflammatory molecules and clinical efficacy to elucidate possible mechanisms for the non-response to infliximab to aid in treatment selection.

MATERIALS AND METHOD

Patients with moderate-to-severe active UC receiving infliximab in our hospital between 2010 and 2016 for whom pre-treatment serum samples were available were retrospectively evaluated. We analyzed the association between serum interleukin (IL)-6, tumor necrosis factor-α (TNF-α) and soluble mucosal vascular addressin cell adhesion molecule-1 (sMAdCAM-1) and the clinical efficacy of infliximab. The primary endpoint was clinical response at the end of the induction period.

RESULTS

Forty-one patients were included in this study. After induction therapy, 27 patients (65.9%) showed a clinical response. Serum IL-6 levels were significantly lower in responders than in non-responders (p = .012), whereas no significant differences were noted in other factors including sMAdCAM-1 and TNF-α. Multivariate analysis identified that serum IL-6 level (odds ratio = 0.72; 95% confidence interval, 0.54-0.96; p = .027) was independently associated with response to infliximab.

CONCLUSIONS

Serum IL-6 level is associated with response to infliximab in UC. Elevated concentrations of IL-6 may provide insight to the mechanism of non-response to infliximab.

Endoscopic scoring indices for evaluation of disease activity in ulcerative colitis

BACKGROUND

Endoscopic assessment of mucosal disease activity is routinely used to determine eligibility and response to therapy in clinical trials of ulcerative colitis. The operating properties of the existing endoscopic scoring indices are unclear.

OBJECTIVES

A systematic review was undertaken to evaluate the development and operating characteristics of endoscopic scoring indices for the evaluation of ulcerative colitis.

SEARCH METHODS

We searched MEDLINE, Embase and CENTRAL from inception to 5 July 2016. We also searched references and conference proceedings (Digestive Disease Week, United European Gastroenterology Week, European Crohn's and Colitis Organization).

SELECTION CRITERIA

Any study design (e.g. randomized controlled trials, cohort studies, case series) that evaluated endoscopic indices for evaluation of ulcerative colitis disease activity were considered for inclusion. Eligible participants were adult patients (> 16 years), diagnosed with ulcerative colitis using conventional clinical, radiologic and endoscopic criteria.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the studies identified from the literature search. These authors also independently extracted and recorded data on the number of patients enrolled; number of patients per treatment arm; patient characteristics including age and gender distribution; endoscopic index; and outcomes such as reliability (intra-rater and inter-rater), validity (content, construct, criterion), responsiveness and feasibility. Any disagreements regarding study inclusion or data extraction were resolved by discussion and consensus with a third author. Risk of bias was assessed by determining whether assessors were blinded to clinical information and whether assessors scored the endoscopic index independently. We also assessed the methodological quality of the validation studies using the COSMIN checklist MAIN RESULTS: A total of 23 reports of 20 studies met the pre-defined inclusion criteria and were included in the review. Of the 20 included validation studies, 19 endoscopic scoring indices were assessed, including the Azzolini Classification, Baron Score, Blackstone Endoscopic Interpretation, Chinese Grading System of Ulcerative Colitis, Endoscopic Activty Index, Jeroen Score, Magnifying Colonoscopy Grade, Matts Score, Mayo Clinic Endoscopic Subscore, Modified Baron Score, Modified Mayo Clinic Endoscopic Subscore, Osada Score, Rachmilewtiz Endoscopic Score, St. Mark's Index, Ulcerative Colitis Colonoscopic Index of Serverity (UCCIS), endoscopic component of the Ulcerative Colitis Disease Activity Index (UCDAI), Ulcerative Colitis Endoscopic Index of Severity (UCEIS), Witts Sigmoidoscopic Score and Watson Grade. The individuals who performed the endoscopic scoring were blinded to clinical and/or histologic information in ten of the included studies, not blinded to clinical and/or histologic information in one of the included studies, and it was unclear whether blinding occurred in the remaining nine included studies. Independent observation was confirmed in four of the included studies, unclear in five of the included studies, and non-applicable (since inter-rater reliability was not assessed) in the remaining eleven included studies. The methodological quality (COSMIN checklist) of most of the included studies was rated as 'good' or 'excellent'. One study that assessed responsiveness was rated as 'fair'. The inter-rater reliability of nine endoscopic scoring indices including the Baron Score, Blackstone Endoscopic Interpretation, Endoscopic Activity Index, Matts Score, Mayo Clinic Endoscopic Subscore, Osada Score, UCCIS, UCEIS, Watson Grade was assessed in seven studies, with estimates of correlation, ƙ, ranging from 0.44 to 0.97. The iIntra-rater reliability of seven endoscopic scoring indices including the Baron Score, Blackstone Endoscopic Interpretation, Matts Score, Mayo Clinic Endoscopic Subscore, Osada Score, UCCIS and UCEIS was assessed in three studies, with estimates of correlation, ƙ, ranging from 0.41 to 0.86. No studies assessed content validity. Three studies evaluated the criterion validity of three endoscopic scoring indices including the Rachmilewitz Endoscopic Score, Magnifying Colonoscopy Grade and the UCCIS. These indices were correlated with objective markers of disease activity including albumin, blood leukocytes, C-reactive protein, fecal calprotectin, hemoglobin, mucosal interleukin-8 concentration and platelet count. Correlation estimates ranged from r = -0.19 to 0.83. Thirteen endoscopic scoring indices were tested for construct validity in 13 studies. Estimates of correlation between the endoscopic scoring indices and other measures of disease activity ranged from r = 0.27 to 0.93. Two studies explored the responsiveness of four endoscopic scoring indices including the Mayo Endoscopic Subscore, Modified Baron Score, Modified Mayo Endoscopic Subscore and UCEIS. One study concluded that the Modified Baron Score, Modified Mayo Endoscopic Subscore and UCEIS had similar responsiveness for detecting disease change in ulcerative colitis. The other included study concluded that the UCEIS may be the most accurate endoscopic scoring tool. None of the included studies formally assessed feasibility.

AUTHORS' CONCLUSIONS

While the UCEIS, UCCIS and Mayo Clinic Endoscopic Subscore have undergone extensive validation, none of these instruments have been fully validated and only two studies assessed responsiveness. Further research on the operating properties of these indices is needed given the lack of a fully-validated endoscopic scoring instrument for the evaluation of disease activity in ulcerative colitis.

The risk factor of clinical relapse in ulcerative colitis patients with low dose 5-aminosalicylic acid as maintenance therapy: A report from the IBD registry

Background

5-Aminosalicylic acids (5-ASA) are effective for ulcerative colitis (UC) as a maintenance therapy. It is not clear when and how to reduce a dose of 5-ASA after inducing remission. We aimed to investigate the clinical characteristics and evaluate the risk factors of relapse for UC patients receiving 5-ASA.

Methods

The medical records of prospectively registered UC patients who received oral 5-ASA as maintenance therapy between January and December 31, 2014, were investigated. The patients’ clinical characteristics in a 2-year follow-up were compared between a relapse group and a remission group.

Results

Of 527 UC patients receiving only oral 5-ASA, 390 (74.0%) maintained remission and 137 (26.0%) relapsed during the follow-up period. Multivariable analysis indicated that a shorter duration of disease remission (p < 0.001, OR: 1.24, 95% CI: 1.12–1.38) was statistically significant for each comparison between the remission and relapse groups among all the patients. Risk factors for clinical relapse were a shorter duration of disease remission (p <0.001, OR: 1.17, 95% CI: 1.04–1.33) in the high-dose 5-ASA group and a shorter duration of disease remission (p = 0.003, OR: 1.45, 95% CI: 1.13–1.89) and a history of steroid use (p = 0.048, OR: 4.73, 95% CI: 1.01–22.2) in the low-dose group.

Conclusions

A dose reduction of 5-ASA might be cautiously selected in UC patients with a history of steroid use and a shorter duration of disease remission.

Efficacy and Usefulness of New Single-Needle Intensive Granulocyte and Monocyte Adsorptive Apheresis in Active Ulcerative Colitis Patients Without Corticosteroids and Biologics

Intensive granulocyte and monocyte adsorptive apheresis (GMA) twice weekly is effective and safe for patients with active ulcerative colitis (UC), but the requirement for maintaining two blood access routes is problematic. Here we compared the efficacy and safety of one-route blood access intensive GMA using a single-needle (SN) and conventional two-route blood access intensive GMA using a double-needle (DN) in patients with active UC not undergoing corticosteroid therapy. Among 80 active UC patients, 38 patients received SN intensive GMA and 42 patients received DN intensive GMA. The clinical remission ratio and mucosal healing ratio at 6 weeks, and the cumulative non-relapse ratio at 52 weeks did not differ significantly between groups. In addition, no serious or mild adverse effects were observed in SN intensive GMA. SN intensive GMA may be an adequate and novel therapeutic option for active UC as an alternative therapy before using corticosteroids.

Neutrophil-to-Lymphocyte Ratio for Predicting Loss of Response to Infliximab in Ulcerative Colitis

Objectives

Neutrophil-to-lymphocyte ratio (NLR) has been used to determine the outcome in malignancies and coronary heart disease. Some reports considered the value of NLR as a predictor of response to infliximab in patients with Crohn’s disease or rheumatoid arthritis; however, no similar studies have been reported for ulcerative colitis (UC). This study aimed to evaluate the clinical significance of the baseline NLR in patients with UC treated by infliximab.

Materials and Methods

Patients with moderate-to-severe active UC who received the first infliximab infusion in our hospital between 2010 and 2015, who showed clinical response during the induction period, were retrospectively evaluated for long-term outcomes and risk factors for loss of response (LOR) during infliximab maintenance therapy. Baseline inflammatory markers including NLR were measured within one week before the initiation of infliximab.

Results

Fifty-nine patients with moderate-to-severe active UC started treatment with infliximab and 37 patients (62.7%) experienced clinical response after induction therapy. Fourteen of 37 patients on maintenance therapy lost the response during follow-up. Baseline NLR of patients with LOR was significantly higher than in patients with sustained response. The NLR cut-off value of 4.488 was predictive of LOR, using receiver operating characteristic analysis (sensitivity: 78.6%, specificity: 78.3%). A univariate analysis revealed a significant relationship between relapse-free survival and the NLR (P = 0.018). Multivariate analysis indicated the NLR as an independent prognostic factor for LOR (hazard ratio = 3.86, 95% confidence interval: 1.20–12.4, P = 0.023).

Conclusions

Baseline NLR is a useful prognostic marker in patients with moderate-to-severe active UC treated with infliximab, and may contribute to appropriate use of infliximab.

Dimethyl Fumarate Reduces Inflammatory Responses in Experimental Colitis

BACKGROUND AND AIMS

Fumaric acid esters have been proven to be effective for the systemic treatment of psoriasis and multiple sclerosis. We aimed to develop a new treatment for colitis.

METHODS

We investigated the effect of dimethylfumarate [DMF, 10-30-100mg/kg] on an experimental model of colitis induced by dinitrobenzene sulphuric acid [DNBS]. We also evaluated the therapeutic activity of 7 weeks' treatment with DMF [30mg/kg] on 9-week-old IL-10KO mice that spontaneously develop a T helper-1 [Th1]-dependent chronic enterocolitis after birth, that is fully established at 8-10 weeks of age. The mechanism of this pharmacological potential of DMF [10 μM] was investigated in colonic epithelial cell monolayers [Caco-2] exposed to H2O2. The barrier function was evaluated by the tight junction proteins.

RESULTS

The treatment with DMF significantly reduced the degree of haemorrhagic diarrhoea and weight loss caused by administration of DNBS. DMF [30 and 100mg/kg] also caused a substantial reduction in the degree of colon injury, in the rise in myeloperoxidase [MPO] activity, and in the increase in tumour necrosis factor [TNF]-α expression, as well as in the up-regulation of ICAM-1 caused by DNBS in the colon. Molecular studies demonstrated that DMF impaired NF-κB signalling via reduced p65 nuclear translocalisation. DMF induced a stronger antioxidant response as evidenced by a higher expression of Mn-superoxide dismutase. Moreover, DMF protected human intestinal epithelial cells against H2O2-induced barrier dysfunction, restoring ZO-1 occludin expression, via the HO-1 pathway.

CONCLUSIONS

DMF treatment reduces the degree of colitis caused by DNBS. We propose that DMF treatment may be useful in the treatment of inflammatory bowel disease.

Approach to Optimize Anti-TNF-α Therapy in Patients With IBD

OPINION STATEMENT

Tumor necrosis factor-α (TNF-α) is an inflammatory cytokine that plays a major role during the initiation and perpetuation of inflammatory bowel disease (IBD). Anti-TNF-α agents are the most widely used biologics that specifically target either or both circulating and membrane-bound TNF-α, thus preventing its pro-inflammatory activity. Despite their efficacy, one third of the patients receiving anti-TNF-α agents are primary non-responders and nearly half of the patients that initially respond may subsequently lose response (secondary loss of response). Many of these cases can be explained by immunogenicity, which can lead to lower drug levels associated with reduced response and serious adverse effects that cause patients to withdraw from treatment. New treatment algorithms instruct practitioners to check drug and antibody levels when there is loss of response, and then provide guidance towards either dose optimization and/or change in the biologic agent or class to help regain efficacy.

Curcumin-piperine mixtures in self-microemulsifying drug delivery system for ulcerative colitis therapy

Curcumin (CUR) is a poorly water-soluble drug and its absorption is very low. In this study, CUR and piperine (PIP) were co-encapsulated into the nanoformulation called self-microemulsifying drug delivery system (SMEDDS) to improve the stability and water-solubility of CUR and enhance its anti-colitis activity. The formulation of CUR-PIP-SMEDDS was prepared to encapsulate two hydrophobic components CUR and PIP, and then was characterized by assessing appearance, morphology, particle size, zeta potential and drug encapsulation efficiency. The appearance of CUR-PIP-SMEDDS remained clarified and transparent, and the microemulsion droplets appeared spherical without aggregation. The mean size of microemulsion droplet formed from CUR-PIP-SMEDDS was 15.87 ± 0.76 nm, and the drug encapsulation efficiency of SMEDDS for CUR and PIP were (94.34 ± 2.18)% and (90.78 ± 2.56)%, respectively. The vitro stability investigation of CUR-PIP-SMEDDS in colon tissue suggested that using SMEDDS as a delivery vehicle and co-encapsulated with PIP, CUR was more stable than drug solution in colons site. Meanwhile, the anti-inflammatory activity of CUR-PIP-SMEDDS was evaluated on DSS-induced colitis model. The results showed that CUR-PIP-SMEDDS exhibited definite anti-colitis activity by directing CUR-PIP-SMEDDS to inflammatory colon tissue through retention enema administration. Our study illustrated that the developed CUR-PIP-SMEDDS formulation was a potential carrier for developing colon-specific drug delivery system of CUR for ulcerative colitis treatment.

Efficacy and safety of tumor necrosis factor-α blockers for ulcerative colitis: A systematic review and meta-analysis of published randomized controlled trials

To evaluate the efficacy and safety of TNF-α blockers for ulcerative colitis. A systematic search for randomized controlled trials (RCTs) of TNF-α blockers for treatment of ulcerative colitis (UC) were performed in PubMed, Web of Science, Embase and cochrane clinical trial. We estimated Pooled estimates of the odds ratio (OR) and relevant 95% confidence interval (CI) using fixed effects model or random effects model as appropriate. Heterogeneity, publication bias, and subgroup analyses were conducted. Nine randomized controlled studies met the selection criteria with a total of 2518 patients. Five studies compared Infliximab with placebo. Two studies compared Infliximab to corticosteroids. Two studies compared Adalimumab to placebo. One study compared subcutaneous golimumab to placebo. Short-term response, short-term remission, long-term remission and mucosal healing were better in the TNF-α blocker group than in the control group (p < 0.05). TNF-α blockers decreased the colectomy rate and serious adverse reactions (p < 0.05). The TNF-α blockers were superior to controls in achieving short-term clinical response/remission, long-term remission and mucosal healing and decreased the colectomy rate and serious adverse reactions.

Adacolumn leucocytapheresis for ulcerative colitis: clinical and endoscopic features of responders and unresponders

Cytokines such as TNF-α have a validated role in the immunopathogensis of ulcerative colitis (UC), and intercepting inflammatory cytokines is currently the best option for maximizing treatment efficacy. One of the major sources of inflammatory cytokines are myeloid linage leucocytes (granulocytes, monocytes), which are present in great numbers in the colonic tissue. Their selective depletion by adsorptive granulocyte, monocyte apheresis (GMA), should be therapeutic in patients with UC, although until now efficacy outcomes have been both encouraging and disappointing. The authors' view is that in patients with UC, there is an evolving scope for therapeutic opportunity based on taking away the sources of inflammatory cytokines, also considering the favorable safety profile of GMA.

The impact of timing and duration of thiopurine treatment on colectomy in ulcerative colitis: a national population-based study of incident cases between 1989-2009

BACKGROUND

The role of thiopurines in altering the risk of colectomy in ulcerative colitis (UC) remains unclear.

AIMS

To examine predictors of colectomy in UC and determine the impact of thiopurines on the risk of colectomy.

METHODS

We constructed a population-based cohort of incident cases of UC in the United Kingdom between 1989 and 2009. We determined trends in thiopurine usage and colectomy for three defined cohorts: era 1 (1989-1995), era 2 (1996-2002), era 3 (2003-2009). We used Cox regression to determine predictors of colectomy and quantified the impact of duration and timing of thiopurine use on the risk of colectomy.

RESULTS

We identified 8673 incident cases of UC. 5-year colectomy rates increased from 4.2%, 5.1% to 6.9% (P = 0.001) for era 1, era 2 and era 3, respectively, despite increasing thiopurine use. This was not significant after adjustment for predictors of colectomy (P = 0.06). There was a higher risk of colectomy in men (HR 1.44, 95% CI: 1.19-1.73), those diagnosed at an early age (HR 1.35, 95% CI: 1.04-1.75; 16-24 vs. 25-64) and early steroid users (HR 1.94, 95% CI: 1.59-2.37). 5-ASA users were less likely to require a colectomy (HR 0.35, 95% CI: 0.28-0.44). Amongst thiopurine users, those treated for greater than 12 months had a 71% reduction in risk of colectomy (HR 0.29, 95% CI: 0.21-0.40). Early thiopurines offered no additional benefit.

CONCLUSIONS

Thiopurine exposure for greater than 12 months reduces the likelihood of colectomy by 71%. Young men and those requiring steroids within 3 months of diagnosis are at greatest risk of colectomy, and most likely to benefit from sustained thiopurine use.

Elevation of PRKCDBP, a novel transcriptional target of TNF-α, and its downregulation by infliximab in patients with ulcerative colitis

BACKGROUND

Protein kinase C delta binding protein (PRKCDBP/Cavin3/hSRBC) is a putative tumor suppressor that is downregulated in many human cancers. Recently, PRKCDBP was identified to be activated by nuclear factor-κB in response to tumor necrosis factor (TNF)-α.

AIMS

To explore the potential of PRKCDBP as a diagnostic or prognostic marker for inflammatory bowel disease, the possible correlation between its expression status and TNF-α signaling was evaluated in ulcerative colitis (UC) patients, both pre- and post-infliximab (IFX) therapy.

METHODS

In total, 31 IFX therapy-naïve patients (13 females; median age, 41 years) with moderate-to-severe UC who had been scheduled for IFX treatment were included. Immunohistochemical analysis of TNF-α and PRKCDBP expression was performed in rectal biopsies.

RESULTS

A significant correlation was observed in immunoreactivity between TNF-α and PRKCDBP. IFX therapy reduced immunohistochemical expression of PRKCDBP and TNF-α (P < 0.001 and P = 0.005, respectively). The mean PRKCDBP expression level decreased from 54.5 to 30.2%, and that of TNF-α decreased from 54.5 to 36.2%. The immunohistochemical expression pre- and post-PRKCDBP therapy correlated significantly with TNF-α levels pre- and post-therapy (Spearman's rank correlation test; P = 0.005 and P = 0.001, respectively).

CONCLUSIONS

These results demonstrate that mucosal expression of PRKCDBP correlated strongly with TNF-α expression in UC patients and that IFX therapy resulted in profound reductions in both PRKCDBP and TNF-α. Thus, these findings support that PRKCDBP expression is tightly controlled by TNF-α, and the anti-inflammatory effect of IFX may in part stem from blockade of the TNF-α-PRKCDBP signaling pathway.

Treating inflammatory bowel disease by adsorptive leucocytapheresis: A desire to treat without drugs

Ulcerative colitis and Crohn’s disease are the major phenotypes of the idiopathic inflammatory bowel disease (IBD), which afflicts millions of individuals throughout the world with debilitating symptoms, impairing function and quality of life. Current medications are aimed at reducing the symptoms or suppressing exacerbations. However, patients require life-long medications, and this can lead to drug dependency, loss of response together with adverse side effects. Indeed, drug side effects become additional morbidity factor in many patients on long-term medications. Nonetheless, the efficacy of anti-tumour necrosis factors (TNF)-α biologics has validated the role of inflammatory cytokines notably TNF-α in the exacerbation of IBD. However, inflammatory cytokines are released by patients’ own cellular elements including myeloid lineage leucocytes, which in patients with IBD are elevated with activation behaviour and prolonged survival. Accordingly, these leucocytes appear logical targets of therapy and can be depleted by adsorptive granulocyte/monocyte apheresis (GMA) with an Adacolumn. Based on this background, recently GMA has been applied to treat patients with IBD in Japan and in the European Union countries. Efficacy rates have been impressive as well as disappointing. In fact the clinical response to GMA seems to define the patients’ disease course, response to medications, duration of active disease, and severity at entry. The best responders have been first episode cases (up to 100%) followed by steroid naïve and patients with a short duration of active disease prior to GMA. Patients with deep ulcers together with extensive loss of the mucosal tissue and cases with a long duration of IBD refractory to existing medications are not likely to benefit from GMA. It is clinically interesting that patients who respond to GMA have a good long-term disease course by avoiding drugs including corticosteroids in the early stage of their IBD. Additionally, GMA is very much favoured by patients for its good safety profile. GMA in 21^st century reminds us of phlebotomy as a major medical practice at the time of Hippocrates. However, in patients with IBD, there is a scope for removing from the body the sources of pro-inflammatory cytokines and achieve disease remission. The bottom line is that by introducing GMA at an early stage following the onset of IBD or before patients develop extensive mucosal damage and become refractory to medications, many patients should respond to GMA and avoid pharmacologics. This should fulfill the desire to treat without drugs.

Reactive oxygen species-scavenging nanomedicines for the treatment of oxidative stress injuries

This Progress Report describes a development of two types of reactive oxygen species (ROS)-scavenging nanomedicines for the treatment of oxidative stress injuries, referred to as pH-sensitive redox nanoparticle (RNP(N) ) and pH-insensitive redox nanoparticle (RNP(O) ), which are prepared by self-assembling amphiphilic block copolymers possessing nitroxide radicals as a side chain of hydrophobic segment via amine and ether linkages, respectively. Due to a protonation of amino groups in hydrophobic core, RNP(N) disintegrates in low pH environments such as ischemic, inflamed, and tumor tissues, resulting in increased ROS-scavenging activity because of the exposed nitroxide radicals from the core. Utilizing pH-responsiveness of RNP(N) , it shows remarkable therapeutic effects on oxidative stress injuries such as renal and cerebral ischemia-reperfusion injuries after intravenous administration. Moreover, RNP(N) shows an enhancement of the activity of anticancer drugs by suppression of activation of transcription factors in tumor due to the ROS scavenging. On the other hand, orally administered RNP(O) has notable characteristics such as preferential accumulation in mucosa and inflamed area of gastrointestinal tract and no uptake into blood stream. Based on these characters, RNP(O) shows a remarkable therapeutic effect for the gastrointestinal inflammation without any adverse effects. Thus, ROS-scavenging nanomedicines have therapeutic efficacy in numerous oxidative stress diseases.

Preparation and properties of a pH sensitive carrier based on three kinds of polymer blend to control the release of 5-amino salicylic acid

CONTEXT

High concentration of 5-amino salicylic acid (5-ASA) in the distal ileum and colon is necessary for the treatment of inflammatory bowel disease (IBD). The control of small molecules, drugs, released from a polymeric matrix remains a great challenge.

OBJECTIVE

To study the preparation and properties of a pH-sensitive carrier for targeting delivery of 5-ASA.

MATERIALS AND METHODS

The carrier was prepared by ternary blends method based on polyvinyl alcohol (PVA), sodium alginate (SA) and polylactic acid. It was characterized by infrared spectrometry and scanning electronic microscopy. The adsorption and release of 5-ASA in different pH media were investigated.

RESULTS

We found out the best ratio of the materials for synthetic carrier. The vector exhibited good performance by the controlled release of the target drug experiment. The adsorption capacity of the carrier for 5-ASA was 70.34% in phosphate buffer saline at pH 1.00, and the release rate was 100.49% in phosphate buffer solution at pH 6.80.

DISCUSSION AND CONCLUSION

PVA is vector backbone of the carrier, and SA plays key role in its pH performance. It is a promising material to effectively deliver 5-ASA to the specific sites of IBD.

Oral nanotherapeutics: effect of redox nanoparticle on microflora in mice with dextran sodium sulfate-induced colitis

BACKGROUND

Patients with ulcerative colitis (UC) exhibit overproduction of reactive oxygen species (ROS) and imbalance of colonic microflora. We previously developed a novel redox nanoparticle (RNP(O)), which effectively scavenged ROS in the inflamed mucosa of mice with dextran sodium sulfate (DSS)-induced colitis after oral administration. The objective of this study was to examine whether the orally administered RNP(O) changed the colonic microflora in healthy mice and those with colitis.

METHODS

RNP(O) was synthesized by self-assembly of an amphiphilic block copolymer that contains stable nitroxide radicals in hydrophobic side chain via ether linkage. Colitis was induced in mice by supplementing DSS in drinking water for 7 days, and RNP(O) was orally administered daily during DSS treatment. The alterations of fecal microflora during treatment of DSS and RNP(O) were investigated using microbiological assays.

RESULTS

We investigated that RNP(O) did not result in significant changes to the fecal microflora in healthy mice. Although total aerobic and anaerobic bacteria were not significantly different between experimental groups, a remarkable increase in commensal bacteria (Escherichia coli and Staphylococcus sp.) was observed in mice with DSS-induced colitis. Interestingly, orally administered RNP(O) remarkably reduced the rate of increase of these commensal bacteria in mice with colitis.

CONCLUSIONS

On the basis of the obtained results, it was confirmed that the oral administration of RNP(O) did not change any composition of bacteria in feces, which strongly suggests a protective effect of RNP(O) on healthy environments in intestinal microflora. RNP(O) may become an effective and safe medication for treatment of UC.

Histologic evaluation of ulcerative colitis: a systematic review of disease activity indices

BACKGROUND

Ulcerative colitis (UC) is an idiopathic inflammatory disorder. Currently, the main goals of treatment are to induce and maintain clinical and/or endoscopic remission. However, evidence indicates that persistent disease activity on colonic biopsies in the setting of clinical or endoscopic remission is an independent predictor of poor outcomes. A number of previous studies have proposed histologic indices for use in specific trials of UC. The aim of this study was to systematically review the existing histological indices for UC and assess their potential use in both patient management and clinical trials.

METHODS

We performed a systematic review of histological indices evaluating disease activity in UC. MEDLINE (Ovid), EMBASE (Ovid), PubMed, the Cochrane Library (CENTRAL), and Digestive Diseases Week (DDW) abstracts of randomized and/or controlled trials clinical trials were searched from inception to February 2013 for applicable studies. Data from these studies were reviewed and analyzed.

RESULTS

After systematically applying inclusion criteria, we identified 108 scientific articles including 88 clinical studies and 21 related clinical reviews. Eighteen indices of histological activity in UC were identified and reviewed.

CONCLUSIONS

Although multiple histological scoring indices for assessment of UC disease activity currently exist, none of these instruments were developed using a formal validation process and their operating properties remain poorly understood. Future studies are needed to address this deficiency.

Duration of disease may predict response to infliximab in pediatric ulcerative colitis

BACKGROUND

Infliximab (IFX) is an established treatment modality for moderate to severe pediatric ulcerative colitis (UC). The purpose of this study was to identify clinical and laboratory parameters, which predict response to IFX in pediatric UC defined by colectomy as the primary outcome measure. Postsurgical complications were examined as well.

METHODS

A retrospective chart review was performed on children younger than 19 years who received IFX therapy at Texas Children's Hospital, Houston, Texas for the treatment of UC from January 2005 to April 2012. Demographics, laboratory data, clinical subtype, duration of disease, transfusion requirement, number of IFX infusions, concurrent medications, and postoperative complication with regard to IFX exposure were examined.

RESULTS

Forty-seven patients (22 male and 25 female; average age at diagnosis: 11.4 y) received IFX. Twenty-six (55.3%) required colectomy, 20 (42.6%) of which occurred within a year of therapy initiation. Disease duration <20 months before IFX initiation, increased the likelihood of a colectomy within a year [OR: 3.8 (95% CI, 1.6-13.3), P=0.044]. Blood transfusion requirement before IFX was associated with higher rates of colectomy within a year [OR: 9.78 (95% CI, 2.2-43.3), P=0.0028]. Preoperative exposure to IFX within 8 weeks did not significantly increase postoperative complications (P=0.26). Serum albumin levels at diagnosis did not predict colectomy.

CONCLUSIONS

Shorter disease duration and need for blood transfusion may be useful indicators of limited response to IFX in pediatric UC.

Efficacy of topical versus oral 5-aminosalicylate for treatment of 2,4,6-trinitrobenzene sulfonic acid-induced ulcerative colitis in rats

5-aminosalicylic acid (5-ASA) is drug of choice for the treatment of ulcerative colitis (UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mechanism of this medication. A flexible tube was inserted into the rat cecum to establish a topical administration model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced UC. A total of 60 rats were divided into sham operation group (receiving an enema of 0.9% saline solution instead of the TNBS solution via the tube), model group, topical 5-ASA group, oral Etiasa group (a release agent of mesalazine used as positive control) and oral 5-ASA group (n=12 each). Different treatments were administered 1 day after UC induction. The normal saline (2 mL) was instilled twice a day through the tube in the sham operation group and model group. 5-ASA was given via the tube in the topical 5-ASA group (7.5 g/L, twice per day, 100 mg/kg), and rats in the oral Etiasa group and oral 5-ASA group intragastrically received Etiasa (7.5 g/L, twice per day, 100 mg/kg) and 5-ASA (7.5 g/L, twice per day, 100 mg/kg), respectively. The body weight was recorded every day. After 7 days of treatment, blood samples were drawn from the heart to harvest the sera. Colonic tissues were separated and prepared for pathological and related molecular biological examinations. The concentrations of 5-ASA were detected at different time points in the colonic tissues, feces and sera in different groups by using the high pressure liquid chromatography (HPLC). The results showed that the symptoms of acute UC, including bloody diarrhea and weight loss, were significantly improved in topical 5-ASA-treated rats. The colonic mucosal damage, both macroscopical and histological, was significantly relieved and the myeloperoxidase activity was markedly decreased in rats topically treated with 5-ASA compared with those treated with oral 5-ASA or Etiasa. The mRNA and protein expression of IL-1β, IL-6, and TNF-α was down-regulated in the colonic tissue of rats topically treated with 5-ASA, significantly lower than those from rats treated with oral 5-ASA or Etiasa. The concentrations of 5-ASA in the colonic tissue were significantly higher in the topical 5-ASA group than in the oral 5-ASA and oral Etiasa groups. It was concluded that the topical administration of 5-ASA can effectively increase the concentration of 5-ASA in the colonic tissue, decrease the expression of proinflammatory cytokines, alleviate the colonic pathological damage and improve the symptoms of TNBS-induced acute UC in rats.

Combination therapy with infliximab and azathioprine is superior to monotherapy with either agent in ulcerative colitis

BACKGROUND & AIMS

The comparative efficacy and safety of infliximab and azathioprine therapy alone or in combination for ulcerative colitis (UC) have not been evaluated previously.

METHODS

This randomized, double-blind trial evaluated the efficacy and safety of 16 weeks of treatment with infliximab monotherapy, azathioprine monotherapy, or the 2 drugs combined in tumor necrosis factor-a antagonist-naive adults with moderate to severe UC. Patients were assigned randomly to receive intravenous infusions of infliximab 5 mg/kg at weeks 0, 2, 6, and 14 plus daily oral placebo capsules; oral azathioprine 2.5 mg/kg daily plus placebo infusions on the infliximab schedule; or combination therapy with the 2 drugs. Corticosteroid-free clinical remission (primary end point, week 16) was evaluated at weeks 8 and 16. The study was terminated before the enrollment target was reached.

RESULTS

A total of 239 patients were included in efficacy analyses. Baseline characteristics were similar between treatment groups. Corticosteroid-free remission at week 16 was achieved by 39.7% (31 of 78) of patients receiving infliximab/azathioprine,compared with 22.1% (17 of 77) receiving infliximab alone(P =.017) and 23.7% (18 of 76) receiving azathioprine alone(P =.032). Mucosal healing at week 16 occurred in 62.8% (49 of 78) of patients receiving infliximab/azathioprine, compared with 54.6% (42 of 77) receiving infliximab (P = .295) and 36.8% (28 of 76) receiving azathioprine (P =.001). Serious infections occurred in 2 patients (1 patient receiving infliximab,and 1 patient receiving azathioprine).

CONCLUSIONS

Anti–tumor necrosis factor-a–naive patients with moderate to severe UC treated with infliximab plus azathioprine were more likely to achieve corticosteroid-free remission at 16 weeks than those receiving either monotherapy. Combination therapy led to significantly better mucosal healing than azathioprine monotherapy. ClinicalTrials.gov number, NCT00537316.

The impact of thiopurines on surgical outcomes in inflammatory bowel disease: do they make a difference?

Ulcerative colitis and Crohn's disease together are known as inflammatory bowel disease (IBD). Surgery is considered for more severe disease and is a dreaded consequence for patients. Thiopurines have proven efficacy in the induction and maintenance of remission of IBD, but the long-term need for surgery remains uncertain with conflicting results from the available studies. The timing and duration of thiopurines also appears to play a pivotal role in the management of these conditions and may also affect the need for surgery. Data from Denmark, Canada, Hungary and the UK appear to suggest a reduction in surgery rates prior to the introduction of anti-tumor necrosis factor (TNF) therapy. The authors aim to review the more recent literature evaluating the surgery rates in IBD and changes in disease trends over time. We ask whether increasing thiopurine prescribing has had an effect on the surgery rates in the era of biologic therapy and whether more aggressive treatment approaches have altered the natural history of IBD.

Infliximab inhibits activation and effector functions of peripheral blood T cells in vitro from patients with clinically active ulcerative colitis

Many patients with inflammatory bowel disease (IBD) are undergoing therapy with infliximab, an antibody specific for TNF. However, the exact mechanisms of action of infliximab are not completely understood. The aim of this study was to determine the in vitro effects of infliximab on blood T cells derived from anti-TNF therapy-naïve ulcerative colitis (UC) patients with clinically active disease. Peripheral blood mononuclear cells were stimulated polyclonally or by antigen in the presence or absence of infliximab. The T cell phenotype was investigated by flow cytometry, cytokine secretion was determined by ELISA, and cell proliferation was determined by thymidine assay or CFSE dye. Presence of infliximab resulted in reduced expression of CD25 in CD4(+) and CD8(+) T cell populations and inhibited secretion of IFN-γ, IL-13, IL-17A, TNF as well as granzyme A. Infliximab also suppressed CD4(+) and CD8(+) T cell proliferation. These effects of infliximab were recorded both in T cells activated by polyclonal and antigen-specific stimulation. The effects of infliximab on T cell apoptosis and induction of FOXP3(+) CD4(+) T regulatory cells were ambiguous and depended on the originating cellular source and/or the stimulation mode and strength. In conclusion, infliximab is able to reduce T cell activation as measured by CD25, proliferation and cytokine secretion in vitro from UC patients with clinically active disease. These data suggest that suppression of T cell activity may be important for infliximab-mediated disease remission in patients with UC.

Ulcerative colitis: prevention of relapse

The clinical management of ulcerative colitis (UC) involves first treating the acute symptoms to induce remission, and then successfully maintaining it. Oral 5-aminosalicylic acids are safe and useful for maintaining remission in patients with UC. In terms of adherence, a once-daily form of 5-aminosalicylic acid is superior in maintaining remission as compared with split dosing. Patients at high risk of relapse may be candidates for treatment with thiopurines and/or biologics in the early stages of UC. Calcineurin inhibitors, such as cyclosporine and tacrolimus, are effective for severe, steroid-refractory UC patients. It is suggested that these patients use thiopurines as their maintenance therapy once they achieve remission with calcineurin inhibitors. Recent studies have confirmed that biologics are effective for inducing clinical and endoscopic remission of UC, and thus they may improve long-term prognosis of UC.

Randomised clinical trial: once- vs. twice-daily prolonged-release mesalazine for active ulcerative colitis

BACKGROUND

Aminosalicylates are first-choice treatment for mild-to-moderately active ulcerative colitis (UC); however, multi-dosing regimens are inconvenient.

AIM

To compare the efficacy and safety of once- (OD) vs. twice- (BD) daily prolonged-release mesalazine (Pentasa, Ferring, Saint-Prex, Switzerland) for active mild-to-moderate UC in a non-inferiority study.

METHODS

Eligible patients (n = 206) were randomised to 8 weeks of mesalazine (4 g/day), either OD with two sachets of 2 g mesalazine granules in the morning (n = 102) or BD with one 2 g sachet in the morning and one in the evening (n = 104). Patients also received 4 weeks of mesalazine enema 1 g/day. Disease activity was assessed at randomisation, weeks 4, 8 and 12 using the UC Disease Activity Index (UC-DAI). Clinical and endoscopic remission (primary endpoint) was assessed after 8 weeks. Patients recorded stool frequency and rectal bleeding in a daily diary.

RESULTS

The primary endpoint, non-inferiority in clinical and endoscopic remission with OD vs. BD mesalazine at 8 weeks, was met (intent-to-treat population: 52.1% vs. 41.8%, respectively, 95% confidence interval -3.4, 24.1; P = 0.14). Improvement of UC-DAI score (92% vs. 79%; P = 0.01) and mucosal healing (87.5% vs. 71.1%; P = 0.007) were significantly better, time to remission significantly shorter (26 vs. 28 days; P = 0.04) and safety similar with OD vs. BD dosing.

CONCLUSIONS

When combined with mesalazine enema, prolonged-release mesalazine once-daily 4 g is as effective and well tolerated as 2 g twice-daily for inducing remission in patients with mild-to-moderately active ulcerative colitis (Clinicaltrials.gov: NCT00737789).

Efficacy, safety and cost analyses in ulcerative colitis patients undergoing granulocyte and monocyte adsorption or receiving prednisolone

Background

Patients with ulcerative colitis (UC) are treated with prednisolone (PSL), which causes adverse side effects. Extracorporeal granulocyte/monocyte adsorption (GMA) with an Adacolumn depletes elevated/activated myeloid lineage leucocytes as sources of inflammatory cytokines. We were interested to evaluate the efficacy, safety and the treatment cost for PSL and GMA.

Methods

Forty-one patients with active UC had achieved remission with GMA, at 1 or 2 sessions/week, up to 10 sessions (n=24) or with orally administered PSL (1mg/kg bodyweight, n=17). Clinical activity index (CAI) ≤4 was considered clinical remission. Following remission, patients received 5-aminosalicylic acid (2250-3000mg/day) or sulphasalazine (4000-6000mg/day) as maintenance therapy and were followed for 600 days. The total treatment cost was assessed based on 1€=150JPY.

Results

PSL was tapered after two weeks, and discontinued when a patient achieved remission. The average time to the disappearance of at least one major UC symptom (haematochezia, diarrhoea, or abdominal discomfort) was 15.3 days in the GMA group and 12.7 days in the PSL group, while time to remission was 27.9 days in the GMA group and 27.6 days in the PSL group, CAI 0.8 and 2.0, respectively. The Kaplan-Meier plots showed similar remission maintenance rates over the 600 days follow-up period. The average medical cost was 12739.4€/patient in the GMA group and 8751.3€ in the PSL group (P<0.05). In the GMA group, 5 transient adverse events were observed vs 10 steroid related adverse events in the PSL group (P<0.001).

Conclusions

In appropriately selected patients, GMA has significant efficacy with no safety concern. The higher cost of GMA vs PSL should be compromised by good safety profile of this non-pharmacological treatment intervention.

An orally administered redox nanoparticle that accumulates in the colonic mucosa and reduces colitis in mice

BACKGROUND & AIMS

Drugs used to treat patients with ulcerative colitis are not always effective because of nonspecific distribution, metabolism in the gastrointestinal tract, and side effects. We designed a nitroxide radical-containing nanoparticle (RNP(O)) that accumulates specifically in the colon to suppress inflammation and reduce the undesirable side effects of nitroxide radicals.

METHODS

RNP(O) was synthesized by assembly of an amphiphilic block copolymer that contains stable nitroxide radicals in an ether-linked hydrophobic side chain. Biodistribution of RNP(O) in mice was determined from radioisotope and electron spin resonance measurements. The effects of RNP(O) were determined in mice with dextran sodium sulfate (DSS)-induced colitis and compared with those of low-molecular-weight drugs (4-hydroxyl-2,2,6,6-tetramethylpiperidine-1-oxyl [TEMPOL] or mesalamine).

RESULTS

RNP(O), with a diameter of 40 nm and a shell of poly(ethylene glycol), had a significantly greater level of accumulation in the colonic mucosa than low-molecular-weight TEMPOL or polystyrene latex particles. RNP(O) was not absorbed into the bloodstream through the intestinal wall, despite its long-term retention in the colon, which prevented its distribution to other parts of the body. Mice with DSS-induced colitis had significantly lower disease activity index and less inflammation following 7 days of oral administration of RNP(O) compared with mice with DSS-induced colitis or mice given low-molecular-weight TEMPOL or mesalamine.

CONCLUSIONS

We designed an orally administered RNP(O) that accumulates specifically in the colons of mice with colitis and is more effective in reducing inflammation than low-molecular-weight TEMPOL or mesalamine. RNP(O) might be developed for treatment of patients with ulcerative colitis.

Surgical treatment of ulcerative colitis in the biologic therapy era

Recently introduced in the treatment algorithms and guidelines for the treatment of ulcerative colitis, biological therapy is an effective treatment option for patients with an acute severe flare not responsive to conventional treatments and for patients with steroid dependent disease. The reduction in hospitalization and surgical intervention for patients affected by ulcerative colitis after the introduction of biologic treatment remains to be proven. Furthermore, these agents seem to be associated with increase in cost of treatment and risk for serious postoperative complications. Restorative proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice in ulcerative colitis patients. Surgery is traditionally recommended as salvage therapy when medical management fails, and, despite advances in medical therapy, colectomy rates remain unchanged between 20% and 30%. To overcome the reported increase in postoperative complications in patients on biologic therapies, several surgical strategies have been developed to maintain long-term pouch failure rate around 10%, as previously reported. Surgical staging along with the development of minimally invasive surgery are among the most promising advances in this field.

A Flare of Ulcerative Colitis Accompanied With Cerebral Sinus Venous Thrombosis And Bilateral Thalamic Infarctus: A Case Report

Ulcerative colitis (UC) is a chronic inflammatory and recurrent disorder that is characterized by bowel inflammation. Some patients with Inflammatory Bowel Disease (IBD) have acute, severe, and sometimes devastating intracranial complications that require immediate medical intervention. Cerebral sinus vein thrombosis is a rare but serious extraintestinal complication associated with ulcerative colitis. Herein we report a 30-year-old man with UC who presented with a flare of gastrointestinal symptoms with mental obtundation and apathy. Total colonoscopy revealed active colitis and cranial MRI showed extensive cerebral sinus venous thrombosis with thalamic infarcts. Because the patient was clinically unstable metilprednisolon with low molecular weight heparin were administered. Two days after treatment the patient was died despite all medical efforts.

Processed blood volume impacts clinical efficacy in patients with ulcerative colitis undergoing adsorptive depletion of myeloid lineage leucocytes

BACKGROUND

Hitherto, therapeutic depletion of granulocytes and monocytes by adsorption (GMA) has been associated with significant and insignificant efficacy in patients with ulcerative colitis (UC). Further, the processed blood volume in one GMA session has been fixed at 30 mL/min × 60 min, regardless of patients' body weight (BW). We were interested to see the efficacy and safety of GMA when administered in relation to patients' BW.

METHODS

Sixty patients were randomly assigned to the routine GMA (n = 30) and to GMA adjusted to patients' BW, 60 mL/kg (n = 30). GMA was done with the Adacolumn, up to 10 sessions over 10 weeks. At entry and 1 week post last GMA, patients were clinically and endoscopically evaluated. Remission was defined as clinical activity index (CAI) ≤4, whereas mucosal remission was defined as endoscopic index (EI) ≤3.

RESULTS

In the BW group, the processed volume/session was 3,260 ± 581 versus 1,800 mL in the routine group (P < 0.001). In the BW group, 25 of 30 patients (83.3%) achieved remission versus 19 of 30 patients (63.3%) in the routine group. The average CAI in the BW group fell from 9.6 ± 2.6 to 2.3 ± 2.1 versus from 9.1 ± 2.4 to 4.0 ± 2.1 (P < 0.05) in the routine group. Similarly, the EI in the BW group fell from 9.4 ± 1.3 to 2.1 ± 2.1 versus from 9.2 ± 1.8 to 4.5 ± 2.3 (P < 0.01).

CONCLUSIONS

GMA adjusted to patients' BW and at a vastly greater processed volume produces significantly higher efficacy as compared with the routine GMA protocol. Further, in this study, up to twofold higher processed volume caused no safety concern.

Probiotics for maintenance of remission in ulcerative colitis

BACKGROUND

Ulcerative colitis is a chronic relapsing disease characterised by diffuse mucosal inflammation limited to the colon. Current maintenance treatments have multiple adverse events and an effective treatment with minimal adverse events is desired. Several studies have demonstrated the importance of intestinal flora in the pathogenesis of ulcerative colitis. It has been suggested that modifying the bacterial flora with probiotics may attenuate the inflammatory process and prevent relapses in ulcerative colitis.

OBJECTIVES

The primary objectives were to determine the efficacy and safety of probiotics for the maintenance of remission in ulcerative colitis.

SEARCH METHODS

The Cochrane Central Register of Controlled Tials (CENTRAL), MEDLINE (1966 to July 2011), EMBASE (1974 to July 2011), CINAHL (1982 to July 2011) and the Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Group Specialised Trial Register were searched. Manufacturers of probiotics were contacted to identify any unpublished trials. References of trials were also searched for any additional trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared probiotics against placebo or any other intervention for the maintenance of remission in ulcerative colitis were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of methodological quality of included studies were independently performed by two authors. The main outcome measure was the occurrence of clinical or endoscopic relapse.

MAIN RESULTS

Four studies (n = 587) met the inclusion criteria and were included in the review. Three trials compared probiotics to mesalazine and one trial compared probiotics with placebo. The studies ranged in length from 3 to 12 months. The risk of bias was high in two studies due to incomplete outcome data and lack of blinding. The methods used for allocation concealment were unclear for all four studies. There was no statistically significant difference between probiotics and mesalazine for maintenance of remission in UC. Relapse was reported in 40.1% of patients in the probiotics group compared to 34.1% of patients in the mesalazine group (3 studies; 555 patients: OR 1.33; 95% CI 0.94 to 1.90 ; I(2) = 11%). There was no statistically significant difference in the incidence of adverse events. Twenty-six per cent of patients in the probiotics group experienced at least one adverse event compared to 24% of patients in the mesalazine group (2 studies; 430 patients OR 1.21; 95% CI 0.80 to 1.84; I(2) =27%). Adverse events reported in the mesalazine-controlled studies include diarrhea, mucous secretion, bloody stools, abdominal pain, flatulence and distension, nausea and vomiting and headache. A small placebo controlled trial (n = 32) found no statistically significant difference in efficacy. Seventy-five per cent of probiotic patients relapsed at one year compared to 92% of placebo patients (OR 0.27; 95% CI 0.03 to 2.68). Adverse events reported in the placebo-controlled study include flatulence, abdominal bloating and pain, changes in faecal consistency, arthralgia, sacroiliitis, tiredness, incontinence, stress, oral blisters, eye dryness, headache, dizziness, influenza, gastroenteritis, cystitis and pneumonia.

AUTHORS' CONCLUSIONS

Given the relatively small number of patients in the pooled analysis, the small number of events and the high risk and unclear risk of bias in the included studies, there is insufficient evidence to make conclusions about the efficacy of probiotics for maintenance of remission in UC. There is a lack of well-designed RCTs in this area and further research is needed.

Cyclosporine-A as a neuroprotective agent against stroke: its translation from laboratory research to clinical application

Stoke remains a leading cause of death and disability with limited treatment options. Extensive research has been aimed at studying cell death events that accompany stroke and how to use these same cell death pathways as potential therapeutic targets for treating the disease. The mitochondrial permeability transition pore (MPTP) has been implicated as a major factor associated with stroke-induced neuronal cell death. MPTP activation and increased permeability has been shown to contribute to the events that lead to cell death. Cyclosporine A (CsA), a widely used immunosuppressant in transplantation and rheumatic medicine, has been recently shown to possess neuroprotective properties through its ability to block the MPTP, which in turn inhibits neuronal damage. This newfound CsA-mediated neuroprotection pathway prompted research on its use to prevent cell death in stroke and other neurological conditions. Preclinical studies are being conducted in hopes of establishing the safety and efficacy guidelines for CsA use in human trials as a potential neuroprotective agent against stroke. In this review, we provide an overview of the current laboratory and clinical status of CsA neuroprotection.

Early mucosal healing with infliximab is associated with improved long-term clinical outcomes in ulcerative colitis

BACKGROUND & AIMS

In the Active Ulcerative Colitis Trial (ACT)-1 and ACT-2, patients with ulcerative colitis treated with infliximab were more likely than those given placebo to have a clinical response, undergo remission, and have mucosal healing. We investigated the association between early improvement (based on endoscopy) and subsequent clinical outcome.

METHODS

Patients underwent endoscopic evaluations at weeks 0, 8, 30, and 54 (ACT-1 only), and were categorized into 4 subgroups by week 8 (Mayo endoscopy subscore, 0-3). The association of week 8 endoscopy subscores, subsequent colectomy risk, symptoms and corticosteroid use outcomes were analyzed. Mucosal healing was defined as a Mayo endoscopy subscore of 0 (normal) or 1 (mild).

RESULTS

Infliximab-treated patients with lower week 8 endoscopy subscores were less likely to progress to colectomy through 54 weeks of follow-up evaluation (P=.0004). This trend was not observed among patients given placebo (P=.47). Patients with lower endoscopy subscores achieved better symptomatic and corticosteroid use outcomes at weeks 30 and 54 (P<.0001, infliximab; P<.01, placebo). Among patients who achieved clinical response at week 8, trends in subsequent clinical outcomes by week 8 endoscopy subscores were generally consistent with that for the overall patient population; no trends were observed among patients who achieved clinical remission.

CONCLUSIONS

The degree of mucosal healing after 8 weeks of infliximab was correlated with improved clinical outcomes including colectomy. Similar trends were observed for all outcomes except colectomy among the subgroup with clinical response at week 8. The degree of mucosal healing at week 8 among those in clinical remission did not predict subsequent disease course.

Update on the management of ulcerative colitis

The treatment options for inflammatory bowel disease have expanded with the introduction of biological therapies. Recently published controlled clinical trials were searched and those that impact the clinical management of ulcerative colitis (UC) are discussed in this review. In the management of mild to moderate UC, mesalamine still remains the first choice of drug. The newly developed once daily formulations have shown equal efficacy to divided doses and possibly portend better compliance owing to a simplified regimen. In outpatients with moderate to severe UC, recent data indicate that infliximab induced and maintained remission leads to decreased colectomy rates and fewer hospitalizations. An alternative anti-tumor necrosis factor (TNF) agent, adalimumab, was also recently shown to be effective for induction of remission in moderate to severe UC. The use of immunosuppressives, such as azathioprine and mercaptopurine, is associated with decreased colectomy rates and thioguanine was shown to be effective in maintaining clinical remission in those who are intolerant to azathioprine/mercaptopurine. In hospitalized patients with steroid resistant severe UC, infliximab and tacrolimus may be alternatives to cyclosporine in those who are otherwise candidates for colectomy. Adequate long-term maintenance therapy with immunosuppressives or anti-TNF therapy is required after rescue therapy for a sustained benefit. Future research is needed to position the available anti-TNF agents and combined immunosuppressive therapy in the treatment of UC to achieve and maintain steroid free remission.

Probiotics in inflammatory bowel diseases and associated conditions

A complex set of interactions between the human genes encoding innate protective functions and immune defenses and the environment of the intestinal mucosa with its microbiota is currently considered key to the pathogenesis of the chronic inflammatory bowel diseases (IBD). Probiotics offer a method to potentially alter the intestinal microbiome exogenously or may provide an option to deliver microbial metabolic products to alter the chronicity of intestinal mucosal inflammation characterizing IBD. At present, there is little evidence for the benefit of currently used probiotic microbes in Crohn's disease or associated conditions affecting extra-intestinal organs. However, clinical practice guidelines are now including a probiotic as an option for recurrent and relapsing antibiotic sensitive pouchitis and the use of probiotics in mild ulcerative colitis is provocative and suggests potential for benefit in select patients but concerns remain about proof from trials.

Clinical trial: a novel high-dose 1 g mesalamine suppository (Salofalk) once daily is as efficacious as a 500-mg suppository thrice daily in active ulcerative proctitis

BACKGROUND

Mesalamine suppositories are first-line therapy in active ulcerative proctitis; the standard regime still recommends multiple doses per day. The primary objective of this study was to show the noninferiority of once-daily administration of a novel 1 g mesalamine suppository versus thrice-daily administration of the 0.5 g mesalamine suppository.

METHODS

This was a single-blind (investigator-blinded), randomized, multicenter, comparative, Phase III clinical trial. Patients with mild to moderately active ulcerative proctitis inserted either one mesalamine 1 g suppository at bedtime or one mesalamine 0.5 g suppository thrice daily over a 6-week period. The primary endpoint was rate of remission (Disease Activity Index below 4).

RESULTS

In all, 354 patients were evaluable for safety and per-protocol analysis. The new regimen demonstrated noninferiority: The percentage of patients with remission was 87.9% for the once-daily 1 g mesalamine suppository and 90.7% for the thrice-daily 0.5 g mesalamine suppository. Each regimen resulted in prompt cessation of clinical symptoms (e.g., median time to ≤3 stools per day (all without blood): 5 days in the 1 g mesalamine once-daily and 7 days in the 0.5 g mesalamine thrice-daily group). Patients preferred applying suppositories once a day.

CONCLUSIONS

In active ulcerative proctitis the once-daily administration of a 1 g mesalamine suppository is as effective and safe, yet considerably more convenient, than the standard thrice-daily administration of a 0.5 g mesalamine suppository.

Long-term follow-up with Granulocyte and Monocyte Apheresis re-treatment in patients with chronically active inflammatory bowel disease

Background

Patients with IBD and chronic inflammation refractory to conventional therapy often demonstrate higher risk of serious complications. Combinations of immunosuppression and biological treatment as well as surgical intervention are often used in this patient group. Hence, there is need for additional treatment options. In this observational study, focused on re-treatment and long-term results, Granulocyte/Monocyte Adsorption (GMA, Adacolumn^®) treatment has been investigated to study efficacy, safety and quality of life in IBD-patients with chronic activity.

Methods

Fifteen patients with ulcerative colitis and 25 patients with Crohn's disease, both groups with chronically active inflammation refractory to conventional medication were included in this observational study. The patients received 5-10 GMA sessions, and the clinical activity was assessed at baseline, after each completed course, and at week 10 and 20 by disease activity index, endoscopy and quality of life evaluation. Relapsed patients were re-treated by GMA in this follow-up study up to 58 months.

Results

Clinical response was seen in 85% and complete remission in 65% of the patients. Ten patients in the UC-group (66%) and 16 patients in the CD-group (64%) maintained clinical and endoscopic remission for an average of 14 months. Fourteen patients who relapsed after showing initial remission were re-treated with GMA and 13 (93%) went into a second remission. Following further relapses, all of seven patients were successfully re-treated for the third time, all of three patients for the fourth time and one for a fifth time.

Conclusions

IBD-patients with chronic inflammation despite conventional therapy seem to benefit from GMA. Re-treatment of relapsing remission patients seems to be effective.

Oral beclomethasone dipropionate in pediatric active ulcerative colitis: a comparison trial with mesalazine

OBJECTIVE

The objective of the study was to evaluate the clinical efficacy of oral beclomethasone diproprionate (BDP) in inducing clinical and endoscopic remission in children with mild to moderate active ulcerative colitis (UC).

PATIENTS AND METHODS

Thirty patients with active UC (pancolitis or left-sided colitis) were enrolled in an open-labeled, randomized, head-to-head study. Group 1 (n = 15) received oral BDP (5 mg/day) for 8 weeks, followed by maintenance therapy with oral mesalazine, 5-aminosalycilate (5-ASA); group 2 (n = 15) received oral 5-ASA (80 mg . kg . day). Assessments were carried out (at 4, 8, and 12 weeks) for clinical scores and for endoscopy (at 12 weeks), together with a final clinical assessment after 1 year follow-up.

RESULTS

Patients treated with BDP showed a significant reduced clinical activity within 4 weeks (P < 0.001 vs pretreatment values) with 80% achieving clinical remission compared with 33% treated with only 5-ASA (P < 0.025). A significant reduction in clinical activity was achieved by 5-ASA after 8 weeks. Comparing clinical activity between BDP and 5-ASA, the former did significantly better at 8 (P < 0.003) and at 12 weeks (P < 0.015). In 73% of BDP-treated patients colonoscopy showed remission compared with 27% of 5-ASA (P < 0.025). Both treatments led to better scores compared with pretreatment values (P < 0.001, both). Erythrocyte sedimentation rate was significantly reduced (P < 0.025 or less) with both treatments, whereas C-reactive protein dropped significantly (P < 0.02) only in BDP.

CONCLUSIONS

Oral BDP was well tolerated and acts significantly faster and more effectively than 5-ASA in inducing clinical remission and endoscopic improvement in pediatric mild-to-moderate UC.

Crucial involvement of the CX3CR1-CX3CL1 axis in dextran sulfate sodium-mediated acute colitis in mice

Ingestion of DSS solution can induce in rodents acute colitis with a massive infiltration of neutrophils and macropahges, mimicking pathological changes observed in the acute phase of UC patients. Concomitantly, DSS ingestion enhanced the expression of a potent macrophage-tropic chemokine, CX3CL1/fractalkine, and its receptor, CX3CR1, in the colon. WT but not CX3CR1-deficient mice exhibited marked body weight loss and shortening of the colon after DSS ingestion. Moreover, inflammatory cell infiltration was attenuated in CX3CR1-deficient mice together with reduced destruction of glandular architecture compared with WT mice. DSS ingestion enhanced intracolonic iNOS expression by macrophages and nitrotyrosine generation in WT mice, but iNOS expression and nitrotyrosine generation were attenuated in CX3CR1-deficient mice. The analysis on bone marrow chimeric mice revealed that bone marrow-derived but not non-bone marrow-derived CX3CR1-expressing cells were a major source of iNOS. These observations would indicate that the CX3CL1-CX3CR1 axis can regulate the expression of iNOS, a crucial mediator of DSS-induced colitis. Thus, targeting the CX3CL1-CX3CR1 axis may be effective for the treatment of IBDs such as UC.