Including Inflammatory Bowel Disease Research Articles

MicroRNA expression in inflammatory bowel disease-associated colorectal cancer.

MicroRNAs (miRNAs) are non-coding RNA molecules composed of 19–25 nucleotides that regulate gene expression and play a central role in the regulation of several immune-mediated disorders, including inflammatory bowel diseases (IBD). IBD, represented by ulcerative colitis and Crohn’s disease, is characterized by chronic intestinal inflammation associated with an increased risk of colorectal cancer (CRC). CRC is one of the most prevalent tumors in the world, and its main risk factors are obesity, physical inactivity, smoking, alcoholism, advanced age, and some eating habits, in addition to chronic intestinal inflammatory processes and the use of immunosuppressants administered to IBD patients. Recent studies have identified miRNAs associated with an increased risk of developing CRC in this population. The identification of miRNAs involved in this tumorigenic process could be useful to stratify cancer risk development for patients with IBD and to monitor and assess prognosis. Thus, the present review aimed to summarize the role of miRNAs as biomarkers for the diagnosis and prognosis of IBD-associated CRC. In the future, therapies based on miRNA modulation could be used both in clinical practice to achieve remission of the disease and restore the quality of life for patients with IBD, and to identify the patients with IBD at high risk for tumor development.

Shikonin contributes to intestinal epithelial cell differentiation through PKM2/NRF2-mediated Polyol pathway

BackgroundAlteration of polyol pathway is a critical event in serials of disease, including inflammatory bowel disease (IBD). Shikonin, an inhibitor of PKM2, has been reported to exert a wide range of biological and pharmacological properties. However, the function of shikonin-mediated polyol pathway in IBD remained to be addressed. MethodsWe conducted WB and qPCR to analyze the effect of shikonin on intestinal epithelial cell differentiation. IF, IP, luciferase assay and ChIP were employed to demonstrate the mechanism that shikonin regulated cell differentiation through polyol pathway. Elisa was used to measure the serum sorbitol in subjects enrolled in this study, and the clinical sample was collected to detect PKM2, AR and NRF2 expression. ResultsHerein, we showed that shikonin treatment in HT-29 and CaCO2 cells not only contributed to CDX2 and its targets expression, including MUC2 and villin, leading to cell differentiation, but also induced NRF2-mediated AKR1B1 and AKR1B10 expression, resulting in increasing AR activity. A synergistic effect on CDX2-mediated cell differentiation was observed in CaCO2 cells in response to cotreatment with shikonin and AR agonist bortezomib for 24 hours, while aldose reductase inhibitor fidarestat treatment in CaCO2 cells reversed the enhanced CDX2 expression caused by shikonin. Mechanistically, PKM2 interacted with NRF2, and this interaction was enhanced in response to shikonin stimulation, resulting in NRF2 phosphorylation and nuclear translocation, which further increased AKR1B1 and AKR1B10 transactivation. Moreover, both AKR1B1 and AKR1B10 expression were decreased, while PKM2 was increased in intestinal epithelial cells labeled with E-cadherin in patients with IBD, and a negative clinical relationship was observed between PKM2 and AKR1B1/AKR1B10, respectively. What's more, the serum sorbitol level was decreased in patients with IBD. ConclusionThese results suggested that shikonin could promote intestinal cell differentiation through NRF2-mediated polyol pathway, implying that shikonin may be a promising therapeutic drug for the treatment of IBD.

Schistosoma japonicum peptide SJMHE1 inhibits acute and chronic colitis induced by dextran sulfate sodium in mice

BackgroundHarnessing helminth-based immunoregulation is a novel therapeutic strategy for many immune dysfunction disorders, including inflammatory bowel diseases (IBDs). We previously identified a small molecule peptide from Schistosoma japonicum and named it SJMHE1. SJMHE1 can suppress delayed-type hypersensitivity, collagen-induced arthritis and asthma in mice. In this study, we assessed the effects of SJMHE1 on dextran sulfate sodium (DSS)-induced acute and chronic colitis.MethodsAcute and chronic colitis were induced in C57BL/6 mice by DSS, following which the mice were injected with an emulsifier SJMHE1 or phosphate-buffered saline. The mice were then examined for body weight loss, disease activity index, colon length, histopathological changes, cytokine expression and helper T (Th) cell subset distribution.ResultsSJMHE1 treatment significantly suppressed DSS-induced acute and chronic colitis, improved disease activity and pathological damage to the colon and modulated the expression of pro-inflammatory and anti-inflammatory cytokines in splenocytes and the colon. In addition, SJMHE1 treatment reduced the percentage of Th1 and Th17 cells and increased the percentage of Th2 and regulatory T (Treg) cells in the splenocytes and mesenteric lymph nodes of mice with acute colitis. Similarly, SJMHE1 treatment upregulated the expression of interleukin-10 (IL-10) mRNA, downregulated the expression of IL-17 mRNA and modulated the Th cell balance in mice with chronic colitis.ConclusionsOur data show that SJMHE1 provided protection against acute and chronic colitis by restoring the immune balance. As a small molecule, SJMHE1 might be a novel agent for the treatment of IBDs without immunogenicity concerns.Graphical abstract

External Model Performance Evaluation of Twelve Infliximab Population Pharmacokinetic Models in Patients with Inflammatory Bowel Disease.

Infliximab is approved for treatment of various chronic inflammatory diseases including inflammatory bowel disease (IBD). However, high variability in infliximab trough levels has been associated with diverse response rates. Model-informed precision dosing (MIPD) with population pharmacokinetic models could help to individualize infliximab dosing regimens and improve therapy. The aim of this study was to evaluate the predictive performance of published infliximab population pharmacokinetic models for IBD patients with an external data set. The data set consisted of 105 IBD patients with 336 infliximab concentrations. Literature review identified 12 published models eligible for external evaluation. Model performance was evaluated with goodness-of-fit plots, prediction- and variability-corrected visual predictive checks (pvcVPCs) and quantitative measures. For anti-drug antibody (ADA)-negative patients, model accuracy decreased for predictions > 6 months, while bias did not increase. In general, predictions for patients developing ADA were less accurate for all models investigated. Two models with the highest classification accuracy identified necessary dose escalations (for trough concentrations < 5 µg/mL) in 88% of cases. In summary, population pharmacokinetic modeling can be used to individualize infliximab dosing and thereby help to prevent infliximab trough concentrations dropping below the target trough concentration. However, predictions of infliximab concentrations for patients developing ADA remain challenging.

Motivational disposition towards psychological characteristics of israeli children with inflammatory bowel diseases: A case-control study

BackgroundPsychological stress is a general and non-specific factor associated with many health conditions, including Inflammatory Bowel Diseases (IBD). It is related not only to external stressors but also to internal characteristics which enhance patients' vulnerability to stress. PurposeTo identify specific psychological characteristics of pediatric IBD related to stress. Design and methodsA case-control-cohort study that compared the psychological characteristics of 49 patients and 56 comparisons. The psychological characteristics were defined by four belief types – beliefs about self, general beliefs, beliefs about norms, and goals – which refer to a set of specific themes. ResultsThe belief types differentiated between the two groups, and the patients were characterized by six themes: like routines, strive to get others' love, caring about the body and the health, doing things only at their own pace, expressing negative emotion without regulations, and feeling over-identification with others. Patients' likelihood of being characterized by the themes is 2.18 to 2.90 times higher than the comparisons. ConclusionChildren with IBD are characterized by a set of specific psychological characteristics. These characteristics were discussed mainly concerning generating chronic stress (e.g., over-identification with others) and interpersonal conflicts (e.g., doing things only at their own pace) among the patients. Implications for practiceIt is suggested to healthcare workers to be aware of the specific psychological characteristics of children with IBD, and sensitive to these characteristics during interactions with them. Besides, the characteristics may pave the way for developing a targeted psychological intervention that corresponds specifically to the patients' needs.

Video capsule endoscopy in inflammatory bowel disease.

Since its introduction into clinical practice in 2000, capsule endoscopy (CE) has become an important procedure for many pathologies of small bowel (SB) diseases, including inflammatory bowel disease (IBD). Currently, the most commonly used capsule procedures are small bowel capsule endoscopy (SBCE), colon CE (CCE), and the recently developed pan‐enteric CE that evaluates the SB and colon in patients with Crohn's disease (CD). SBCE has a higher diagnostic performance compared to other radiological and conventional endoscopic modalities in patients with suspected CD. Additionally, CE plays an important role in monitoring the activity of CD in SB. It can also be used in evaluating response to anti‐inflammatory treatment and detecting recurrence in postsurgical patients with CD who underwent bowel resection. Due to its increasing use, different scoring systems have been developed specifically for IBD. The main target with CCE is ulcerative colitis (UC). The second‐generation colon capsule has shown high performance for the assessment of inflammation in patients with UC. CCE allows noninvasive evaluation of mucosal inflammation with a reduced volume of preparation for patients with UC.

Histone deacetylase inhibitors regulate vitamin C transporter functional expression in intestinal epithelial cells

Intestinal absorption of vitamin C in humans is mediated via the sodium-dependent vitamin C transporters (hSVCT1 and hSVCT2). hSVCT1 and hSVCT2 are localized at the apical and basolateral membranes, respectively, of polarized intestinal epithelia. Studies have identified low plasma levels of vitamin C and decreased expression of hSVCT1 in patients with several inflammatory conditions including inflammatory bowel disease (IBD). Investigating the underlying mechanisms responsible for regulating hSVCT1 expression are critical for understanding vitamin C homeostasis, particularly in conditions where suboptimal vitamin C levels detrimentally affect human health. Previous research has shown that hSVCT1 expression is regulated at the transcriptional level, however, little is known about epigenetic regulatory pathways that modulate hSVCT1 expression in the intestine. In this study, we found that hSVCT1 expression and function were significantly decreased in intestinal epithelial cells by the histone deacetylase inhibitors (HDACi), valproic acid (VPA), and sodium butyrate (NaB). Further, expression of transcription factor HNF1α, which is critical for SLC23A1 promoter activity, was significantly down regulated in VPA-treated cells. Chromatin immunoprecipitation (ChIP) assays showed significantly increased enrichment of tetra-acetylated histone H3 and H4 within the SLC23A1 promoter following VPA treatment. In addition, knockdown of HDAC isoforms two, and three significantly decreased hSVCT1 functional expression. Following VPA administration to mice, functional expression of SVCT1 in the jejunum was significantly decreased. Collectively, these in vitro and in vivo studies demonstrate epigenetic regulation of SVCT1 expression in intestinal epithelia partly mediated through HDAC isoforms two and three.

A Retinoid X Receptor Agonist Directed to the Large Intestine Ameliorates T-Cell-Mediated Colitis in Mice.

Retinoid X receptor (RXR) is a nuclear receptor that heterodimerizes with several nuclear receptors, integrating ligand-mediated signals across the heterodimers. Synthetic RXR agonists have been developed to cure certain inflammatory diseases, including inflammatory bowel diseases (IBDs). However, pre-existing RXR agonists, which are lipophilic and readily absorbed in the upper intestine, cause considerable adverse effects such as hepatomegaly, hyperlipidemia, and hypothyroidism. To minimize these adverse effects, we have developed an RXR agonist, NEt-3IB, which has lipophilic and thus poorly absorptive properties. In this study, we evaluated the effects of NEt-3IB in an experimental murine colitis model induced through the adoptive transfer of CD45RBhighCD4+ T cells. Pharmacokinetic studies demonstrated that the major portion of NEt-3IB was successfully delivered to the large intestine after oral administration. Notably, NEt-3IB treatment suppressed the development of T cell-mediated chronic colitis, as indicated by improvement of wasting symptoms, inflammatory infiltration, and mucosal hyperplasia. The protective effect of NEt-3IB was mediated by the suppression of IFN-γ-producing Th1 cell expansion in the colon. In conclusion, NEt-3IB, a large intestine-directed RXR agonist, is a promising drug candidate for IBDs.

Anti-inflammatory and -apoptotic effects of a long-term herbal extract treatment on DSS-induced colitis in mice fed with high AGEs-fat diet

BackgroundObesity is associated with many comorbidities including inflammatory bowel disease (IBD). We investigated prophylactic effects of an herbal extract (HE) on the DSS-induced colitis mice challenged with high AGEs-fat diet 60% (HFD).MethodsSix-week-old C57BL/6 male mice were fed with either HFD (8 groups, 6 mice in each group), or normal diet (ND) (8 groups, 6 mice in each group). After 6 weeks, animals received HE (combination of turmeric, ginger, boswellia and cat’s claw extract) for 7 weeks in three doses (high dose (0.6 mg/g); low dose (0.15 mg/g) and mid dose (0.3 mg/g)). Next, mice were subjected to 2.5% DSS in drinking water. Control mice received ND and instead of HE and DSS they received distilled water. Obesity index markers were determined, H&E staining and TUNEL assay evaluated apoptosis. Colonic expressions of IL-6, RAGE, AGER1, Sirt1, Bax, Bcl2, ZO-1 and P53 were determined.ResultsHE ameliorated colitis in HFD mice by reducing colonic myeloperoxidase activity (by 2.3-fold), macrophage accumulation (by 2.6-fold) and mRNA expression of IL-6 (by 2.3-fold) in HFD mice. Moreover, HE restored ZO-1 (by 2.7-fold), prevented apoptosis and maintained immune homeostasis. HE reduced activation of NF-κB protein (by 1.3-fold) through decreasing RAGE (by 1.93-fold) and up-regulation of Sirt1 (by 7.71-fold) and prevented down-regulation of DDOST (by 6.6-fold) in HFD mice.ConclusionsHE ameliorated colitis in prophylactic in HFD mice and it was, at least partly, due to the restoration of the gut integrity, suppression of inflammation and apoptosis via modulation of colonic Sirt1, RAGE and DDOST signaling.Graphic abstract

Effect of comorbid mood and anxiety disorders on breast and cervical cancer screening in immune-mediated inflammatory disease.

We aimed to examine rates of breast and cervical cancer screening in women with immune-mediated inflammatory diseases (IMID), including inflammatory bowel disease (IBD), multiple sclerosis (MS) and rheumatoid arthritis (RA) versus a matched cohort with IMID; and examine the association of psychiatric comorbidity with screening in these populations. We conducted a retrospective cohort study in Manitoba, Canada using administrative data. We identified women with IBD, MS and RA, and controls without these IMID matched on age and region. Annually, we identified individuals with any active mood/anxiety disorder. Using physician claims, we determined the proportion of each cohort who had cervical cancer screening within three-year intervals, and mammography screening within two-year intervals. We modeled the difference in the proportion of the IMID and matched cohorts who underwent mammography; and pap tests using log-binomial regression with generalized estimating equations, adjusting for sociodemographics, comorbidity and immune therapy use. We tested for additive interactions between cohort and mood/anxiety disorder status. During 2006–2016, we identified 17,230 women with IMID (4,623 with IBD, 3,399 with MS, and 9,458 with RA) and 85,349 matched controls. Having an IMID was associated with lower (-1%) use of mammography; however, this reflected a mixture of more mammography in the IBD cohort (+2.9%) and less mammography in the MS (-4.8 to -5.2%) and RA (-1.5%) cohorts. Within the IBD, MS and RA cohorts, having an active mood/anxiety disorder was associated with more mammography use than having an inactive mood/anxiety disorder. The MS and RA cohorts were less likely to undergo Pap testing than their matched cohorts. In the absence of an active mood/anxiety disorder, the IBD cohort was more likely to undergo Pap testing than its matched cohort; the opposite was true when an active mood/anxiety disorder was present. Among women with an IMID, mood/anxiety disorder influence participation in cancer screening.

Tissue-dependent transcriptional and bacterial associations in primary sclerosing cholangitis-associated inflammatory bowel disease

Background: Primary sclerosing cholangitis (PSC) is a disease of the bile duct and liver. However, patients frequently have co-morbidities including inflammatory bowel disease (IBD) and colorectal cancer. Colorectal cancer risk in patients with PSC-associated ulcerative colitis (PSC/UC) is elevated relative to patients with ulcerative colitis (UC) alone, reasons for which remain obscure. Further, clinical and immunological features, and involved intestinal sites differ between PSC/UC and UC. Understanding the molecular and microbial basis for differences in cancer risk between these two patient groups and how these differ across intestinal sites is important for the development of therapies to prevent colorectal cancer development in at-risk individuals. Methods: We employed ribonucleic acid sequencing (RNA-seq) analysis of biopsy samples across three intestinal tissue locations (ileum, caecum and rectum) in patients with PSC/UC (n = 8), UC (n = 10) and healthy controls (n = 12) to determine tissue-dependent transcriptional alterations in PSC/UC. We also performed 16S ribosomal RNA (rRNA) amplicon sequencing to determine bacterial associations with PSC/UC and host-microbiome associations. Results: Tissue-defining transcriptional signatures revealed that the ileum was enriched for genes involved in lipid and drug metabolism, the caecum for activated immune cells and the rectum for enteric neurogenesis. Transcriptional alterations relative to healthy control samples were largely shared between patients with PSC/UC or UC although were distinct across tissue locations. Nevertheless, we observed reduced expression of gamma-glutamyl transferase 1 ( GGT1) specifically in the ileum and caecum of patients with PSC/UC. Analysis of the bacterial component of the microbiome revealed high inter-individual variability of microbiome composition and little evidence for tissue-dependency. We observed a reduction in Parabacteroides relative abundance in the rectum of patients with PSC/UC. Conclusions: The role of gamma-glutamyl transferase in maintaining the redox environment through the glutathione salvage pathway makes our observed alterations a potential pathway to PSC-associated colorectal cancer.

The Phenotypic Difference of IgA Nephropathy and its Race/Gender-dependent Molecular Mechanisms.

IgA nephropathy (IgAn), defined by the pre dominant de position of IgA in the glomerular mesangium, is the most common form of GN throughout the world. However, its incidence, sex distribution, clinical presentation, and progression and pathogenic initiating factors are largely variable and do not fit such a simple definition. To assess the heterogeneity of this disease, we recently conducted a clinical survey on the presentation and clinical management of patients with IgAn in Europe and Japan. This clinical survey highlights similarities and differences in patients from different cont inents. The survey revealed obvious differences between nations in the frequency of gastrointestinal complications, including inflammatory bowel diseases (IBD) and celiac disease, which were more frequent in European patients. Such findings are compatible with susceptibility loci related to intestinal immunity and IBD in recent genome wide association studies (GWAS) on IgAn. However, most of the molecules in these mucosal-related loci fulfill the immunologic function not only of gut-associated lymphoid tissue (GALT), but also nasopharyngeal/bronchial-associated lymphoid tissues (NALT/BALT). Indeed, a similar frequency of macrohematuria coinciding with upper respiratory infection, a hallmark manifestation of this disease, was found in the survey, emphasizing the pathogenic roles of these molecules in the NALT/BALT of patients with IgAn. Recent experimental and clinical studies including GWAS on multiple common infections and IBD indicate immune crosstalk between GALT and NALT/BALT, and some related mediators, such as TNF superfamily ligands (APRIL/BAFF). This review explains the epidemiologic heterogeneity of this disease with the clinical survey, and discusses race and sex-dependent molecular mechanisms.

Hair EDX Analysis-A Promising Tool for Micronutrient Status Evaluation of Patients with IBD?

Micronutrient deficiencies can arise in various conditions, including inflammatory bowel diseases (IBD), and diagnosing these deficiencies can be challenging in the absence of specific clinical signs. The aim of this study was to evaluate the status of various trace elements hair concentration in IBD patients compared to a healthy control group and to identify potential correlations between the micronutrient status and relevant parameters related to disease activity. The concentrations of iron, magnesium, calcium, zinc, copper, manganese, selenium and sulfur in the hair of 37 IBD patients with prior diagnosed IBD (12 Crohn’s disease and 25 ulcerative colitis) and 31 healthy controls were evaluated by Energy Dispersive X-Ray spectroscopy (EDX). Significant differences in hair concentration profile of studied trace elements were identified for IBD patients compared to healthy controls. A significantly decreased hair concentration of iron, magnesium, calcium and selenium and a significantly increased sulfur hair concentration were observed in IBD patients at the time of evaluation. A decreased hair calcium concentration (r = −0.772, p = 0.003) and an increased sulfur concentration (r = 0.585, p = 0.046) were significantly correlated with disease activity. Conclusion: Hair mineral and trace elements evaluation may contribute to a proper evaluation of their status in IBD patients and improving the management of nutritional status of IBD patients.

Epstein–Barr Virus DNA Exacerbates Colitis Symptoms in a Mouse Model of Inflammatory Bowel Disease

Infection with EBV has been associated with various inflammatory disorders including inflammatory bowel diseases (IBD). Contribution of this virus to intestinal disease processes has not been assessed. We previously detected that EBV DNA triggers proinflammatory responses via the activation of endosomal Toll-like receptor (TLR) signaling. Hence, to examine the colitogenic potential of EBV DNA, we used the dextran sodium sulfate (DSS) mouse colitis model. C57BL/6J mice received either DSS-containing or regular drinking water. Mice were then administered EBV DNA by rectal gavage. Administration of EBV DNA to the DSS-fed mice aggravated colonic disease activity as well as increased the damage to the colon histologic architecture. Moreover, we observed enhanced expression of IL-17A, IFNγ and TNFα in colon tissues from the colitis mice (DSS-treated) given the EBV DNA compared to the other groups. This group also had a marked decrease in expression of the CTLA4 immunoregulatory marker. On the other hand, we observed enhanced expression of endosomal TLRs in colon tissues from the EBV DNA-treated colitis mice. These findings indicate that EBV DNA exacerbates proinflammatory responses in colitis. The ubiquity of EBV in the population indicates that possible similar responses may be of pertinence in a relevant proportion of IBD patients.

Mesenchymal Stem Cell-Macrophage Crosstalk and Maintenance of Inflammatory Microenvironment Homeostasis.

Macrophages are involved in almost every aspect of biological systems and include development, homeostasis and repair. Mesenchymal stem cells (MSCs) have good clinical application prospects due to their ability to regulate adaptive and innate immune cells, particularly macrophages, and they have been used successfully for many immune disorders, including inflammatory bowel disease (IBD), acute lung injury, and wound healing, which have been reported as macrophage-mediated disorders. In the present review, we focus on the interaction between MSCs and macrophages and summarize their methods of interaction and communication, such as cell-to-cell contact, soluble factor secretion, and organelle transfer. In addition, we discuss the roles of MSC-macrophage crosstalk in the development of disease and maintenance of homeostasis of inflammatory microenvironments. Finally, we provide optimal strategies for applications in immune-related disease treatments.

Crohn\u2019s disease and ulcerative colitis patient-reported outcomes signs and symptoms for the remote management of inflammatory bowel disease during the COVID-19 pandemic

Background and aimsThe COVID-19 pandemic has led to a deep reorganization of hospital services including inflammatory bowel disease (IBD) units. In this situation, conversion of in-person routine follow-up visits into phone consultations might be necessary. Here we explored the feasibility of using the validated Crohn’s Disease (CD) or Ulcerative Colitis (UC) Patient-Reported Outcomes Signs and Symptoms (CD- and UC-PRO/SS) to collect data about abdominal symptoms (abdominal/S) and bowel signs and symptoms (bowel/SS) remotely.MethodsCD- and UC-PRO/SS were collected during phone consultations and compared among patients with active and inactive disease. The effectiveness of therapeutic intervention in patients with active disease was assessed by PRO/SS variation.ResultsTwenty-one CD and 56 UC patients were evaluated by phone. Six (28.6%) CD and 15 (26.8%) UC patients were considered to have active disease. In CD the bowel/SS but not the abdominal/S module was significantly higher in active patients (mean bowel/SS 2.50 [SE ± 0.44] active vs 0.76 [SE ± 0.18] remission, p = 0.008, AUC 0.87; mean abdominal/S 1.11 [SE ± 0.38] active vs 0.24 [SE ± 0.13] remission, p = 0.066). UC-PRO/SS measures were significantly higher in active patients as compared to patients in remission (median bowel/SS 1.63 [SE ± 0.24] active vs 0.33 [SE ± 0.04] remission; p < 0.0001, AUC 0.91; mean abdominal/S 1.03 [SE ± 0.24] vs 0.37 [SE ± 0.12]; p = 0.009, AUC 0.71). Therapy was escalated in 12 patients (3 CD and 9 UC) due to disease relapse. Therapy escalation resulted in the reduction of PRO/SS as evaluated at the subsequent phone consultation.ConclusionsPRO/SS might represent a feasible tool to evaluate disease activity and therapy outcome in IBD patients during periods of limited access to outpatient clinics.

Herbal Plants: The Role of AhR in Mediating Immunomodulation.

The prevalence of chronic inflammatory diseases including inflammatory bowel disease (IBD), autoimmunity and cancer have increased in recent years. Herbal-based compounds such as flavonoids have been demonstrated to contribute to the modulation of these diseases although understanding their mechanism of action remains limited. Flavonoids are able to interact with cellular immune components in a distinct way and influence immune responses at a molecular level. In this mini review, we highlight recent progress in our understanding of the modulation of immune responses by the aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor whose activity can be regulated by diverse molecules including flavonoids. We focus on the role of AhR in integrating signals from flavonoids to modulate inflammatory responses using in vitro and experimental animal models. We also summarize the limitations of these studies. Medicinal herbs have been widely used to treat inflammatory disorders and may offer a valuable therapeutic strategy to treat aberrant inflammatory responses by modulation of the AhR pathway.

Intestinal mesenchymal cells regulate immune responses and promote epithelial regeneration in vitro and in dextran sulfate sodium-induced experimental colitis in mice.

Disruption of the intestinal mucosal tolerance, that is, the immunological unresponsiveness to innocuous food antigens and the commensal microbiota, in the colon is associated with several chronic diseases including inflammatory bowel disease (IBD). Understanding the mechanisms responsible for intestinal mucosal tolerance has potential translational value for its therapy and management. Human intestinal mesenchymal cells (iMCs) play important roles in colonic mucosal tolerance, but further studies on their tissue regenerative and immunomodulatory capacities are necessary in order to fully understand their function in health and disease. In this study, we have isolated and analysed the capacity of human iMCs to promote wound healing and modulate immune responses in vitro and in vivo, using the dextran sulfate sodium (DSS)-induced colitis model. Cultured iMCs were CD45- CD73+ CD90+ CD105+ and accelerated the wound closure in a normal colon mucosa (NCM) 356 human epithelial cell wound healing assay. Furthermore, iMCs blocked the LPS-mediated induction of TNF-α in THP-1 macrophages and inhibited the proliferation of peripheral blood mononuclear cells, partly through the induction of indoleamine-2,3-dioxygenase. In DSS colitic mice, iMCs administration reduced the disease activity index and ameliorated intestinal tissue damage and permeability. Furthermore, iMCs reduced intestinal inflammation, evidenced by a decreased mRNA expression of pro-inflammatory cytokines, reduced IL-1β secretion by intestinal explants and inhibited colonic iNOS protein expression. Our data show that human iMCs isolated from the noninflamed intestine possess tissue-regenerative and immunomodulatory capacities that could potentially be harnessed/restored in order to reduce IBD severity.

Gp130 Signaling in NOD2-Driven Crohn’s Disease: A Key Player in Fibrosis and a Novel Target for Refractory Patients

Gp130 Signaling in NOD2-Driven Crohn’s Disease: A Key Player in Fibrosis and a Novel Target for Refractory Patients

ILEOSCOPY: WHEN ILEAL EVALUATION IS NOT MANDATORY DURING COLONOSCOPY.

Ileitis is defined as ileal inflammation, with several etiologies, including inflammatory bowel disease (IBD), and can be evaluated during the colonoscopy exam, but its mandatory evaluation is discussed, because of few diagnosis and procedure time. This study aims to evaluate the correlation of colonoscopic ileitis with the clinical presentation, in order to identify the cases where ileal examination is mandatory. A retrospective, cross-sectional study was conducted between 2013 and 2017. The examination report, indications for colonoscopy, and medical records were evaluated in order to identify whether the colonoscopic findings were clinically significant. Patients over 18 years of age who had undergone ileoscopy were included, whereas patients below 18 years of age, those with previous intestinal resections, and repeated examinations of the same patient in the study period were excluded. The estimated association measure was the odds ratio with 95% confidence intervals. P-values <0.05 indicated statistical significance. A total of 3382 cases were included. Among these participants, 64.5% were females and the average age was 56.9±13.1 years (18-89 years). Ileal alterations were observed in 5.3% of the patients, with 2.69% being clinically significant between all patients, and 0.96% excluding those with IBD. There was a positive correlation between the ileitis findings and IBD control examinations and a negative correlation in screening and change in bowel habit indications. Among the indications with ileitis clinically significant, IBD control still had a positive correlation, 'diarrhea' and 'others' did not show a statistical significance, and all other indications presented a negative correlation for ileal assessment. Ileal evaluation in only mandatory in IBD control. When the main colonoscopy objective is detecting colonic neoplasms, ileoscopy is unnecessary.