Inflammatory bowel disease therapy: current state-of-the-art

Mice carrying an epithelial deletion of the glucocorticoid receptor NR3C1 develop a higher tumor load in experimental colitis-associated cancer

The glucocorticoid receptor NR3C1 is expressed in multiple cell types in the gut and elsewhere. Intestinal epithelial cells both produce and respond to glucocorticoids in different physiological and pathological contexts. In experimental colitis, glucocorticoids have been shown to exert a dual role, dampening inflammation while producing a deterioration in animal status, including death. Mice with tamoxifen-inducible, intestinal epithelial-specific deletion of NR3C1 (NR3C1^ΔIEC mice) are protected against experimental colitis, suggesting glucocorticoid epithelial actions are deleterious. Since glucocorticoids modulate epithelial proliferation, it follows that they may affect the development of colon cancer. In this study, we set out to test this hypothesis using the dextran sulfate sodium-azoxymethane model of colitis-associated cancer. Knockout (KO) mice were found to exhibit a twofold higher tumor load but similar incidence and tumor size. Tumors had a higher trend to extend close to the submucosal layer (36% vs. 0%) in NR3C1^ΔIEC mice, and overexpressed Lgr5, Egfr, and Myc, consistent with distinct expression of proliferative/stemness markers. Snai1 and Snai2 were upregulated specifically in tumors of NR3C1^ΔIEC mice, suggesting enhanced epithelial to mesenchymal transition in the absence of the intestinal epithelial glucocorticoid (GC) receptor. We conclude that endogenous GC epithelial signaling is involved in colitis-associated cancer.NEW & NOTEWORTHY Mice carrying a tamoxifen-inducible deletion of the glucocorticoid receptor in intestinal epithelial cells (NR3C1^ΔIEC mice) and their corresponding controls were subjected to the azoxymethane-dextran sulfate sodium model of colitis-associated cancer. KO mice exhibit a twofold higher tumor load, with a higher trend to extend close to the submucosal layer (36% vs. 0%), but with similar incidence and tumor size. Colonic tumors in NR3C1^ΔIEC mice showed signs of increased neoplastic transformation and tumor-associated inflammation.

Update on the therapeutic management of patients with either psoriatic arthritis or ulcerative colitis: focus on the JAK inhibitor tofacitinib

Psoriatic arthritis (PsA) and ulcerative colitis (UC) are immune-mediated diseases that cause significant burden worldwide. Recent advances in their management have improved patient outcomes. However, significant unmet needs still remain as not all patients respond to current treatments, and patients may lose responsiveness over time. An improved understanding of the pathophysiology of these diseases has brought about the development of novel disease-modifying agents, including interleukin inhibitors and, more recently, Janus kinase (JAK) inhibitors. With the approval of tofacitinib for the treatment of adults with active PsA and in adult patients with moderately-to-severely active UC, JAK inhibitors have recently entered the treatment armamentarium for PsA and UC. A number of other JAK inhibitors are also undergoing clinical development and are currently in phase III trials. This review provides an overview of the current therapeutic options for PsA and UC, with a focus on the JAK inhibitors.

A Comparative Study on the Efficacy of NLRP3 Inflammasome Signaling Inhibitors in a Pre-clinical Model of Bowel Inflammation

Nucleotide-binding oligomerization domain leucine rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome is pivotal in maintaining intestinal homeostasis and sustaining enteric immune responses in the setting of inflammatory bowel diseases. Drugs acting as NLRP3 blockers could represent innovative strategies for treatment of bowel inflammation. This study was performed in rats with dinitrobenzenesulfonic acid (DNBS)-induced colitis, to investigate how the direct blockade of NLRP3 inflammasome with an irreversible inhibitor (INF39) compares with Ac-YVAD-cmk (YVAD, caspase-1 inhibitor) and anakinra (IL-1β receptor antagonist), acting downstream on NLRP3 signaling. Animals with DNBS-colitis received YVAD (3 mg/kg) or anakinra (100 mg/Kg) intraperitoneally, and INF39 (25 mg/kg) or dexamethasone (DEX, 1 mg/kg) orally for 6 days, starting on the same day of colitis induction. Under colitis, there was a body weight decrease, which was attenuated by YVAD, anakinra or INF39, but not DEX. All test drugs counteracted the increase in spleen weight. The colonic shortening and morphological colonic alterations associated with colitis were counteracted by INF39, anakinra and DEX, while YVAD was without effects. Tissue increments of myeloperoxidase, tumor necrosis factor and interleukin-1β were more effectively counteracted by INF39 and DEX, than YVAD and anakinra. These findings indicate that: (1) direct inhibition of NLRP3 inflammasome with INF39 is more effective than caspase-1 inhibition or IL-1β receptor blockade in reducing systemic and bowel inflammatory alterations; (2) direct NLRP3 inhibition can be a suitable strategy for treatment of bowel inflammation.

Paradigm Shift of Healthcare Cost for Patients with Inflammatory Bowel Diseases: A Claims Data-Based Analysis in Japan

Anti-tumor necrosis factor-α (anti-TNFα) agents are used for induction and maintenance of remission in patients with inflammatory bowel diseases (IBD). However, biologic drugs present a large economic burden on health insurance systems. We aimed to estimate the mean annual health care cost per patient with IBD and cost contribution of anti-TNFα agents. We performed an analysis of patients with Crohn’s disease (CD) and ulcerative colitis (UC) based on a large-scale administrative claims database constructed by Japan Medical Data Center (JMDC) Co. Ltd., comprising inpatient, outpatient, and pharmacy claims data. We evaluated all claims from 1 April 2013 through 31 March 2016. Descriptive statistics were used to measure median health care costs paid per member per year (PMPY) and the relative cost contribution of anti-TNFα agents. A total 1405 patients with CD and 5771 with UC were included. Median costs PMPY were approximately six times higher for CD than UC (JPY 1,957,320 and JPY 278,760, respectively). Medication cost for anti-TNFα agents was the main cost driver, accounting for 59.9% and 17.8% of the total costs for CD and UC, respectively. In Japan, costs for anti-TNFα agents have resulted in drug costs exceeding inpatient costs for IBD. Optimized use of anti-TNFα agents and introduction of biosimilars for anti-TNFα agents can be expected to substantially reduce the health care costs of IBD.

Lignosulfonic acid attenuates NF-κB activation and intestinal epithelial barrier dysfunction induced by TNF-α/IFN-γ in Caco-2 cells

Lentinula edodes mycelia solid culture extract (MSCE) is used as a medical food ingredient and provides beneficial effects to patients with cancer and chronic type C hepatitis. Low molecular weight lignin (LM-lignin), which is an active component of MSCE, exhibits hepatoprotective, antitumor, antiviral, and immunomodulatory effects. In this study, we investigated the effect of LM-lignin/lignosulfonic acid on intestinal barrier function. Lignosulfonic acid enhanced transepithelial membrane electrical resistance in human intestinal Caco-2 cell monolayers. In Caco-2 cells treated with lignosulfonic acid, expression of claudin-2, which forms high conductive cation pores in tight junctions (TJs), was decreased. Lignosulfonic acid also attenuated the barrier dysfunction that is caused by tumor necrosis factor (TNF)-α and interferon (IFN)-γ in Caco-2 cells. TNF-α- and IFN-γ-induced activation of NF-κB, such as translocation of NF-κB p65 into the nucleus and induction of gene expression, was inhibited by lignosulfonic acid treatment. Furthermore, lignosulfonic acid decreased the TNF-α- and IFN-γ-induced increase in interleukin (IL)-1β and IL-6 expression in Caco-2 cells. These results suggest that lignosulfonic acid not only enhances TJ barrier function but also restores TJ barrier integrity impaired by inflammatory cytokines. Therefore, lignosulfonic acid may be beneficial for the treatment of inflammation-induced intestinal barrier dysfunction observed in inflammatory bowel disease.

The effects of body image impairment on the quality of life of non-operated Portuguese female IBD patients

OBJECTIVES

Inflammatory bowel diseases (IBD) and their treatment are known to negatively impact on patients' body image, especially female patients. However, although there are broad evidences of body image impairment in female IBD patients, its negative impact on the quality of life (QoL) of non-operated women is not clearly and specifically studied. The aim of the current study was therefore to analyse, in a sample of non-operated female IBD patients, the factors that contribute to body image impairment and its impact on QoL.

METHODS

Ninety-six non-operated women (39.7 % with CD and 60.3 % with UC), aged between 18 and 40 years old, completed an online survey with validated self-report measures, which included the Body Image Scale and the WHO Brief Quality of Life Assessment Scale.

RESULTS

Negative body image was correlated with lower psychological and physical QoL and increased corticosteroids use, associated medical complications, body mass index (BMI), and IBD symptomatology. Regression analyses revealed that BMI and IBD symptomatology significantly predicted body image impairment. Furthermore, results from path analyses indicated that BMI and IBD symptomatology's effect on psychological and physical QoL was mediated through the negative effects of body image impairment. This model explained 31 % of psychological QoL and 41 % of physical QoL.

CONCLUSIONS

These findings suggest that non-operated female patients are subject to pervasive and harmful effects of body image impairment on psychological and physical functioning. Therefore, psychological interventions aiming to target body dissatisfaction should be implemented in the health care of IBD, independently of patients' operative status.

A medicoeconomic review of early intervention with biologic agents in the treatment of inflammatory bowel diseases

The treatment of inflammatory bowel disease with standard therapy fails to control the disease in many patients. Biologic therapy has an increasing role in altering the natural history of Crohn’s disease and ulcerative colitis, and is improving patient prognosis. However, indications for treatment and issues with drug costs and value for money remain unclear. Also, when to perform early intervention with biologic agents is at present unclear. We performed an extensive literature search and review to address these issues. The biologics provide better care for many patients. The choice of biologic agent, the indications for its use, the switch between agents, and the considerations of cost are outlined, with a view to guiding the treating physician in managing these cases. Outstanding issues and anticipated future developments are defined.

Adipose mesenchymal stromal cell function is not affected by methotrexate and azathioprine

Given their capacity to modulate the immune response, adipose mesenchymal stem or stromal cells (ASCs) have been used as therapeutic tools to treat chronic inflammatory and autoimmune diseases both in preclinical and clinical studies. Patients enrolled in such clinical trials are often concomitantly treated with immunomodulatory drugs such as methotrexate (MTX) or azathioprine (AZA). Therefore it is necessary to investigate the possible impact of these drugs on ASC function to learn if there are any interactions that would affect the therapeutic effects of either component and thus the clinical outcome of the trials. ASCs were cultured in the absence or presence of MTX or AZA and the effects on viability, proliferation, immunomodulatory properties, and immunogenic features were studied in vitro. The drugs did not affect the viability and proliferative capacity of ASCs. When the drugs and the ASCs were concomitantly used to inhibit lymphocyte proliferation, no synergistic or antagonizing inhibitory effects were found. MTX and AZA did not impair the capacity of ASCs to induce the generation of regulatory T cells in vitro. These data confirm that the immunomodulating features of ASCs are fully functional after exposure to these drugs. Interestingly, whereas MTX did not affect the capacity of natural killer (NK) cells to lyse allogeneic ASCs in vitro, AZA protected allogeneic ASCs from NK cell lysis.

Role of surgery in pediatric ulcerative colitis

Pediatric ulcerative colitis (UC) has a more extensive and progressive clinical course than adult UC. Therefore, more aggressive initial therapies and more frequent surgical treatments are needed. The therapeutic goal is to gain clinical and laboratory control of the disease with minimal adverse effects while permitting the patient to function as normally as possible. Approximately 5-10 % of patients with UC require acute surgical intervention because of fulminant colitis refractory to medical therapy. Mucosal proctocolectomy with ileal J-pouch anal anastomosis is currently recommended as a standard curative surgical procedure for UC in both children and adults worldwide. This review will focus on the current issues regarding the surgical indications for pediatric UC, the technical details of procedures and results of most recent published series to take the most appropriate next step to improve the surgical outcomes and patients' quality of life.

Adalimumab treatment in Crohn's disease: an overview of long-term efficacy and safety in light of the EXTEND trial

The advent of anti-tumor necrosis factor (TNF) therapies revolutionized the treatment of inflammatory bowel disease. Adalimumab is a subcutaneous anti-TNF agent indicated for use in patients with moderate-to-severe Crohn’s disease and those with moderate-to-severe ulcerative colitis. In both diseases, it can be used for both induction of remission and for maintenance of remission. This review focuses on its use in Crohn’s disease as described in the EXTEND (Extend the Safety and Efficacy of Adalimumab through Endoscopic Healing) trial. Several clinical trials using traditional instruments to measure clinical response have had endoscopic substudies looking for endoscopic healing. The EXTEND trial is the first to use mucosal healing on endoscopy as a primary endpoint for patients with moderate-to-severe Crohn’s disease and baseline ulcerative disease treated with continuous adalimumab. In this well designed trial, the primary endpoint was narrowly missed, but the secondary endpoints further the notion that mucosal healing should be a more mainstream measure of drug efficacy. How this will translate from clinical trials to the clinic is not yet clear, but identifying noninvasive markers for mucosal healing, and understanding the implications of mucosal healing for safety, resource utilization, and quality of life are all worthy targets for further study. The aim of this review is to understand the role of mucosal healing, safety profile, and efficacy in patients treated with anti-TNF therapy, with particular attention to adalimumab and the EXTEND trial.

Pediatric ulcerative colitis: current treatment approaches including role of infliximab

Ulcerative colitis is a chronic inflammatory bowel disease that can lead to derangements in the growth, nutritional status, and psychosocial development of affected children. There are several medical options for the induction and maintenance of disease remission, but the benefits of these medications need to be carefully weighed against the risks, especially in the pediatric population. As the etiology of the disease has become increasingly understood, newer therapeutic alternatives have arisen in the form of biologic therapies, which are monoclonal antibodies targeted to a specific protein or receptor. This review will discuss the classical treatments for children with ulcerative colitis, including 5-aminosalicylates, corticosteroids, thiopurine immunomodulators, and calcineurin inhibitors, with a particular focus on the newer class of anti-tumor necrosis factor-α agents.

Insights into inflammatory bowel disease using Toxoplasma gondii as an infectious trigger

Oral infection of certain inbred mouse strains with the protozoan Toxoplasma gondii triggers inflammatory pathology resembling lesions seen during human inflammatory bowel disease, in particular Crohn's disease (CD). Damage triggered by the parasite is largely localized to the distal portion of the small intestine, and as such is one of only a few models for ileal inflammation. This is important because ileal involvement is a characteristic of CD in over two-thirds of patients. The disease induced by Toxoplasma is mediated by Th1 cells and the cytokines tumor necrosis factor-α and interferon-γ. Inflammation is dependent upon IL-23, also identified by genome-wide association studies as a risk factor in CD. Development of lesions is concomitant with emergence of E. coli that display enhanced adhesion to the intestinal epithelium and subepithelial translocation. Furthermore, depletion of gut flora renders mice resistant to Toxoplasma-triggered ileitis. Recent findings suggest complex CCR2-dependent interactions between lamina propria T cells and intraepithelial lymphocytes in fueling proinflammatory pathology in the intestine. The advantage of the Toxoplasma model is that disease develops rapidly (within 7-10 days of infection) and can be induced in immunodeficient mice by adoptive transfer of mucosal T cells from infected donors. We propose that Toxoplasma acts as a trigger setting into motion a series of events culminating in loss of tolerance in the intestine and emergence of pathogenic T cell effectors. The Toxoplasma trigger model is providing new leaps in our understanding of immunity in the intestine.