Increased production of tumour necrosis factor-alpha interleukin-1 beta, and interleukin-6 by morphologically normal intestinal biopsies from patients with Crohn's disease

Combined plasma protein and memory T cell profiling discern IBD-patient-immunotypes related to intestinal disease and treatment outcomes

Inflammatory bowel disease (IBD) chronicity results from memory T helper cell (Tmem) reactivation. Identifying patient-specific immunotypes is crucial for tailored treatment. We conducted a comprehensive study integrating circulating immune proteins and circulating Tmem, with intestinal tissue histology and mRNA analysis, in therapy-naïve pediatric IBD (Crohn's disease, CD: n = 62; ulcerative colitis, UC: n = 20; age-matched controls n = 43), and after 10-12 weeks' induction therapy. At diagnosis, plasma protein profiles unveiled two UC and three CD clusters with distinct disease courses. UC patients displayed unchanged circulating Tmem, while CD exhibited increased frequencies of gut-homing ex-Th17, known for high IFN-γ production. UC#2 had elevated Th17/neutrophil-pathway-related proteins and severe disease, with higher endoscopic and histological damage and Th17/neutrophil infiltration. Although both UC#1 and UC#2 responded to therapy, UC#2 required earlier immunomodulation. CD#3 had lower plasma protein concentrations, especially IFN-γ pathway proteins, fewer gut-homing ex-Th17 and clinically milder disease, confirmed by intestinal gene expression. CD#1 and CD#2 had comparably high Th1-related immune profiles, but CD#1 exhibited higher concentrations of proteins previously associated with poorer prognosis. Both CD clusters responded to induction therapy, with similar one-year outcomes. This study highlights feasibility of discriminating patient-specific immunotypes in IBD, advancing our understanding of immune pathogenesis, needed for tailored treatment strategies.

Probiotic Bacillus licheniformis MCC2514 and Bifidobacterium breve NCIM 5671 Regulates GATA3 and Foxp3 Expression in the Elevated Disease Condition

TNBS-induced ulcerative colitis was evaluated using Bacillus licheniformis MCC 2514 (B. licheniformis) and Bifidobacterium breve NCIM 5671 (Bf. breve) as immune modulators. The study aims to analyze probiotic efficiency of ulcerative colitis induced by TNBS in Wistar rats. The tumor-like structure was found in the colon of TNBS inflammation-induced rats. Nitric oxide production was inhibited by about 65.2% fed with combination of bacteria and C-reactive protein, and decreased by 12% and 10.8% upon supplementing B. licheniformis and Bf. breve against the TNBS-treated rats, respectively. Liver damage was observed in the TNBS-treated rats; addition of probiotic bacteria reduced SGPT (75.4%) and SGOT (42.5%). On TNBS treatment, the transcriptional factor responsible for Th2 cell immune response (GATA3) was analyzed, and the elevation in gene expression (5.31-fold) was found. The FOXP-3 responsible for T-regulatory cells was expressed about 0.91-fold upon the treatment with a combination of bacteria. The expression of antioxidant genes such as iNOS (1.11-fold), GPx (1.29-fold), and PON1 (1.48-fold) has been increased when compared with that of the TNBS-treated group. The cytokines specific to Th2-driven immune response, such as IL-4, IL-5, and TNF-α, were reduced upon feeding the bacteria. It is observed that the B. licheniformis and Bf. breve used in the study have reduced Th2-driven immune response.

Attenuation of Chronic Inflammation in Intestinal Organoids with Graphene Oxide-Mediated Tumor Necrosis Factor-α_Small Interfering RNA Delivery

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract with a complex and multifactorial etiology, making it challenging to treat. While recent advances in immunomodulatory biologics, such as antitumor necrosis factor-α (TNF-α) antibodies, have shown moderate success, systemic administration of antibody therapeutics may lead to several adverse effects, including the risk of autoimmune disorders due to systemic cytokine depletion. Transient RNA interference using exogenous short interfering RNA (siRNA) to regulate target gene expression at the transcript level offers an alternative to systemic immunomodulation. However, siRNAs are susceptible to premature degradation and have poor cellular uptake. Graphene oxide (GO) nanoparticles have been shown to be effective nanocarriers for biologics due to their reduced cytotoxicity and enhanced bioavailability. In this study, we evaluate the therapeutic efficacy of GO mediated TNF-α_siRNA using in vitro models of chronic inflammation generated by treating murine small intestines (enteroids) and large intestines (colonoids) with inflammatory agents IL-1β, TNF-α, and LPS. The organotypic mouse enteroids and colonoids developed an inflammatory phenotype similar to that of IBD, characterized by impaired epithelial homeostasis and an increased production of inflammatory cytokines such as TNF-α, IL-1β, and IL-6. We assessed siRNA delivery to these inflamed organoids using three different GO formulations. Out of the three, small-sized GO with polymer and dendrimer modifications (smGO) demonstrated the highest transfection efficiency, which led to the downregulation of inflammatory cytokines, indicating an attenuation of the inflammatory phenotype. Moreover, the transfection efficiency and inflammation-ameliorating effects could be further enhanced by increasing the TNF-α_siRNA/smGO ratio from 1:1 to 3:1. Overall, the results of this study demonstrate that ex vivo organoids with disease-specific phenotypes are invaluable models for assessing the therapeutic potential of nanocarrier-mediated drug and biologic delivery systems.

Biological Potential and Bioaccessibility of Encapsulated Curcumin into Cetyltrimethylammonium Bromide Modified Cellulose Nanocrystals

Curcumin is a natural phenolic compound with important biological functions. Despite its demonstrated efficacy in vitro, curcumin biological activities in vivo are dependent on its bioaccessibility and bioavailability, which have been highlighted as a crucial challenge. Cetyltrimethylammonium bromide-modified cellulose nanocrystals (CNC-CTAB) have been shown to be effective in curcumin encapsulation, as they have the potential to enhance biological outcomes. This study evaluated the biological effects of curcumin encapsulated within CNC-CTAB structures, namely its antioxidant, anti-inflammatory and antimicrobial properties, as well as the release profile under digestion conditions and intestinal permeability. Encapsulated curcumin demonstrated antioxidant and anti-inflammatory properties, effectively reducing reactive oxygen species and cytokine production by intestinal cells. The delivery system exhibited antimicrobial properties against Campylobacter jejuni bacteria, further suggesting its potential in mitigating intestinal inflammation. The system showed the ability to protect curcumin from degradation and facilitate its interaction with the intestinal epithelium, highlighting the potential of CNC-CTAB as carrier to enhance curcumin intestinal biological functions.

Gut microbiota interacts with inflammatory responses in acute pancreatitis

Acute pancreatitis (AP) is one of the most common acute abdominal conditions, and its incidence has been increasing for years. Approximately 15-20% of patients develop severe AP (SAP), which is complicated by critical inflammatory injury and intestinal dysfunction. AP-associated inflammation can lead to the gut barrier and function damage, causing dysbacteriosis and facilitating intestinal microbiota migration. Pancreatic exocrine deficiency and decreased levels of antimicrobial peptides in AP can also lead to abnormal growth of intestinal bacteria. Meanwhile, intestinal microbiota migration influences the pancreatic microenvironment and affects the severity of AP, which, in turn, exacerbates the systemic inflammatory response. Thus, the interaction between the gut microbiota (GM) and the inflammatory response may be a key pathogenic feature of SAP. Treating either of these factors or breaking their interaction may offer some benefits for SAP treatment. In this review, we discuss the mechanisms of interaction of the GM and inflammation in AP and factors that can deteriorate or even cure both, including some traditional Chinese medicine treatments, to provide new methods for studying AP pathogenesis and developing therapies.

Usefulness of Proguanylin, Pentraxin 3 and S100A12 Serum Concentrations in Diagnosis and Monitoring the Disease Activity in Crohn's Disease

The aim of our case-control study was to identify novel biomarkers of Crohn's disease (CD) that hold the potential to be employed in both disease diagnosis and monitoring activity. In the context of the contribution of intestinal barrier integrity and immune response to the pathogenesis of CD, we assessed the serum concentrations of proguanylin (pro-GN), pentraxin 3 (PTX3) and S100A12 in 20 patients before and after anti-inflammatory treatment, as well as in 20 healthy individuals. Statistical analyses revealed a significant difference in the levels of pro-GN (5.5 vs. 11.35, p < 0.001), PTX3 (2117.9 vs. 1608.37, p < 0.05) and S100A12 (79.4 vs. 19.74, p < 0.001) between pretreatment patients with CD and healthy individuals. Moreover, we noted a significant relationship between the serum profile of PTX3 and disease activity, expressed as CDAI, both before (p < 0.005, r = 0.63) and after (p < 0.05, r = 0.60) treatment. A similar correlation was noted in the case of S100A12 (p < 0.005, r = 0.81), albeit exclusively within the post-treatment group of patients. Anti-inflammatory treatment resulted in an elevation of pro-GN concentration (5.5 vs. 8.04, p < 0.001) and a reduction in PTX3 level (2117.9 vs. 1609.5, p < 0.05) in the serum of patients with CD. In comparison to our previous research conducted on a group of patients with ulcerative colitis (UC), those with CD exhibited reduced levels of PTX3 (2117.9 vs. 3197.05, p < 0.005) and elevated concentrations of S100A12 (79.4 vs. 39.36, p < 0.05). The results obtained from this investigation suggest that measurements of pro-GN, PTX3 and S100A12 could prove beneficial in the diagnosis of Crohn's disease. Assessment of changes in the serum profile of PTX3 appears to be a good marker of response to treatment but also, along with analysis of S100A12 protein serum levels, a useful marker in differentiating CD from UC.

Dietary (poly)phenols mitigate inflammatory bowel disease: Therapeutic targets, mechanisms of action, and clinical observations

Inflammatory bowel diseases (IBD), which include Crohn's disease and ulcerative colitis, are a rapidly growing public health concern worldwide. These diseases are heterogeneous at the clinical, immunological, molecular, genetic, and microbial level, but characteristically involve a disrupted immune-microbiome axis. Shortcomings in conventional treatment options warrant the need for novel therapeutic strategies to mitigate these life-long and relapsing disorders of the gastrointestinal tract. Polyphenols, a diverse group of phytochemicals, have gained attention as candidate treatments due to their array of biological effects. Polyphenols exert broad anti-inflammatory and antioxidant effects through the modulation of cellular signaling pathways and transcription factors important in IBD progression. Polyphenols also bidirectionally modulate the gut microbiome, supporting commensals and inhibiting pathogens. One of the primary means by which gut microbiota interface with the host is through the production of metabolites, which are small molecules produced as intermediate or end products of metabolism. There is growing evidence to support that modulation of the gut microbiome by polyphenols restores microbially derived metabolites critical to the maintenance of intestinal homeostasis that are adversely disrupted in IBD. This review aims to define the therapeutic targets of polyphenols that may be important for mitigation of IBD symptoms, as well as to collate evidence for their clinical use from randomized clinical trials.

Biomarkers of Intestinal Injury in Colic

Biomarkers are typically proteins, enzymes, or other molecular changes that are elevated or decreased in body fluids during the course of inflammation or disease. Biomarkers pose an extremely attractive tool for establishing diagnoses and prognoses of equine gastrointestinal colic, one of the most prevalent causes of morbidity and mortality in horses. This topic has received increasing attention because early diagnosis of some forms of severe colic, such as intestinal ischemia, would create opportunities for rapid interventions that would likely improve case outcomes. This review explores biomarkers currently used in equine medicine for colic, including acute phase proteins, proinflammatory cytokines, markers of endotoxemia, and tissue injury metabolites. To date, no single biomarker has been identified that is perfectly sensitive and specific for intestinal ischemia; however, L-lactate has been proven to be a very functional and highly utilized diagnostic tool. However, further exploration of other biomarkers discussed in this review may provide the key to accelerated identification, intervention, and better outcomes for horses suffering from severe colic.

Geometric engineering of organoid culture for enhanced organogenesis in a dish

Here, we introduce a facile, scalable engineering approach to enable long-term development and maturation of organoids. We have redesigned the configuration of conventional organoid culture to develop a platform that converts single injections of stem cell suspensions to radial arrays of organoids that can be maintained for extended periods without the need for passaging. Using this system, we demonstrate accelerated production of intestinal organoids with significantly enhanced structural and functional maturity, and their continuous development for over 4 weeks. Furthermore, we present a patient-derived organoid model of inflammatory bowel disease (IBD) and its interrogation using single-cell RNA sequencing to demonstrate its ability to reproduce key pathological features of IBD. Finally, we describe the extension of our approach to engineer vascularized, perfusable human enteroids, which can be used to model innate immune responses in IBD. This work provides an immediately deployable platform technology toward engineering more realistic organ-like structures in a dish.

Soluble Protein Hydrolysate Ameliorates Gastrointestinal Inflammation and Injury in 2,4,6-Trinitrobenzene Sulfonic Acid-Induced Colitis in Mice

Inflammatory bowel diseases (IBD) are chronic, recurring gastrointestinal diseases that severely impair health and quality of life. Although therapeutic options have significantly expanded in recent years, there is no effective therapy for a complete and permanent cure for IBD. Well tolerated dietary interventions to improve gastrointestinal health in IBD would be a welcome advance especially with anticipated favorable tolerability and affordability. Soluble protein hydrolysate (SPH) is produced by the enzymatic hydrolysis of commercial food industry salmon offcuts (consisting of the head, backbone and skin) and contains a multitude of bioactive peptides including those with anti-oxidant properties. This study aimed to investigate whether SPH ameliorates gastrointestinal injury in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced mouse colitis model. Mice were randomly assigned to four groups: Control (no colitis), Colitis, Colitis/CP (with control peptide treatment), and Colitis/SPH (with SPH treatment). Colitis was induced by cutaneous sensitization with 1% TNBS on day −8 followed by 2.5% TNBS enema challenge on day 0. Control peptides and SPH were provided to the mice in the Colitis/CP or Colitis/SPH group respectively by drinking water at the final concentration of 2% w/v daily from day −10 to day 4. Then, the colon was harvested on day 4 and examined macro- and microscopically. Relevant measures included disease activity index (DAI), colon histology injury, immune cells infiltration, pro- and anti-inflammatory cytokines and anti-oxidative gene expression. It was found that SPH treatment decreased the DAI score and colon tissue injury when compared to the colitis-only and CP groups. The protective mechanisms of SPH were associated with reduced infiltration of CD4⁺ T, CD8⁺ T and B220⁺ B lymphocytes but not macrophages, downregulated pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-6), and upregulated anti-inflammatory cytokines (transforming growth factor-β1 and interleukin-10) in the colon tissue. Moreover, the upregulation of anti-oxidative genes, including ferritin heavy chain 1, heme oxygenase 1, NAD(P)H quinone oxidoreductase 1, and superoxide dismutase 1, in the colons of colitis/SPH group was observed compared with the control peptide treatment group. In conclusion, the protective mechanism of SPH is associated with anti-inflammatory and anti-oxidative effects as demonstrated herein in an established mice model of colitis. Clinical studies with SPH as a potential functional food for the prevention or as an adjuvant therapy in IBD may add an effective and targeted diet-based approach to IBD management in the future.

The Complexity and Multiplicity of the Specific cAMP Phosphodiesterase Family: PDE4, Open New Adapted Therapeutic Approaches

Cyclic nucleotides (cAMP, cGMP) play a major role in normal and pathologic signaling. Beyond receptors, cyclic nucleotide phosphodiesterases; (PDEs) rapidly convert the cyclic nucleotide in its respective 5'-nucleotide to control intracellular cAMP and/or cGMP levels to maintain a normal physiological state. However, in many pathologies, dysregulations of various PDEs (PDE1-PDE11) contribute mainly to organs and tissue failures related to uncontrolled phosphorylation cascade. Among these, PDE4 represents the greatest family, since it is constituted by 4 genes with multiple variants differently distributed at tissue, cellular and subcellular levels, allowing different fine-tuned regulations. Since the 1980s, pharmaceutical companies have developed PDE4 inhibitors (PDE4-I) to overcome cardiovascular diseases. Since, they have encountered many undesired problems, (emesis), they focused their research on other PDEs. Today, increases in the knowledge of complex PDE4 regulations in various tissues and pathologies, and the evolution in drug design, resulted in a renewal of PDE4-I development. The present review describes the recent PDE4-I development targeting cardiovascular diseases, obesity, diabetes, ulcerative colitis, and Crohn's disease, malignancies, fatty liver disease, osteoporosis, depression, as well as COVID-19. Today, the direct therapeutic approach of PDE4 is extended by developing allosteric inhibitors and protein/protein interactions allowing to act on the PDE interactome.

Inflammatory Bowel Disease: A Review of Pre-Clinical Murine Models of Human Disease

Crohn’s disease (CD) and ulcerative colitis (UC) are both highly inflammatory diseases of the gastrointestinal tract, collectively known as inflammatory bowel disease (IBD). Although the cause of IBD is still unclear, several experimental IBD murine models have enabled researchers to make great inroads into understanding human IBD pathology. Here, we discuss the current pre-clinical experimental murine models for human IBD, including the chemical-induced trinitrobenzene sulfonic acid (TNBS) model, oxazolone and dextran sulphate sodium (DSS) models, the gene-deficient I-kappa-B kinase gamma (Iκκ-γ) and interleukin(IL)-10 models, and the CD4⁺ T-cell transfer model. We offer a comprehensive review of how these models have been used to dissect the etiopathogenesis of disease, alongside their limitations. Furthermore, the way in which this knowledge has led to the translation of experimental findings into novel clinical therapeutics is also discussed.

Anti-TNF therapy and immunogenicity in inflammatory bowel diseases: a translational approach

Inflammatory bowel diseases are chronic illnesses that involve intestinal inflammation and are usually diagnosed as Crohn's disease or ulcerative colitis. As these diseases do not have a cure, the goal of treatment is to induce and maintain remission. Monoclonal antibodies have been recognized as the most advanced therapy to avoid complications and reduce the need for surgical approaches. However, although their effectiveness has been proven by several studies, they can trigger the immune system, induce the occurrence of immunogenicity, which may lead to the loss of response and treatment failure. The purpose of this review is to determine what are the main mechanisms involved in IBD; to assess the recommended treatments; to explore the mechanisms of immunogenicity. We also try to explain the detection and describe the existing advances that make possible the clinical application of these approaches.

Fecal Microbiome Changes and Specific Anti-Bacterial Response in Patients with IBD during Anti-TNF Therapy

Inflammatory bowel diseases (IBD) are chronic disorders of the gastrointestinal tract that have been linked to microbiome dysbiosis and immune system dysregulation. We investigated the longitudinal effect of anti-TNF therapy on gut microbiota composition and specific immune response to commensals in IBD patients. The study included 52 patients tracked over 38 weeks of therapy and 37 healthy controls (HC). To characterize the diversity and composition of the gut microbiota, we used amplicon sequencing of the V3V4 region of 16S rRNA for the bacterial community and of the ITS1 region for the fungal community. We measured total antibody levels as well as specific antibodies against assorted gut commensals by ELISA. We found diversity differences between HC, Crohn's disease, and ulcerative colitis patients. The bacterial community of patients with IBD was more similar to HC at the study endpoint, suggesting a beneficial shift in the microbiome in response to treatment. We identified factors such as disease severity, localization, and surgical intervention that significantly contribute to the observed changes in the gut bacteriome. Furthermore, we revealed increased IgM levels against specific gut commensals after anti-TNF treatment. In summary, this study, with its longitudinal design, brings insights into the course of anti-TNF therapy in patients with IBD and correlates the bacterial diversity with disease severity in patients with ulcerative colitis (UC).

Dietary Exposure to the Food Contaminant Deoxynivalenol Triggers Colonic Breakdown by Activating the Mitochondrial and the Death Receptor Pathways

INTRODUCTION

The food contamination by mycotoxins is of increasing public health concerns. Deoxynivalenol (DON), a mycotoxin contaminating cereals, has been associated with the exacerbation of inflammatory bowel diseases (IBD), thereby raising the question of its role in the development of IBD. Moreover, the effect of DON on the colon is poorly described.

METHODS AND RESULTS

Wistar rats exposed (1-4 weeks) to low doses of DON (2 or 9 mg kg^-1 feed) show microscopic alterations of colonic tissue (dilated lymphatic vessels, luminal debris, and cubic and flattened enterocytes). Ingestion of DON also alters colonic functions by increasing paracellular permeability while reducing the expression of the tight junction proteins and increased apoptosis in colonic tissue. Pro-apoptotic factors Bax/Bak, cytochrome C, and caspase 9 are upregulated, whereas expression of anti-apoptotic protein Bcl2 tends to decrease for the mitochondrial pathway. An increased expression of FasR and caspase-8 is observed for the extrinsic pathway. An increase in the pro-inflammatory markers TNFα, IL-17, and myeloperoxidase is also observed.

CONCLUSION

These results indicate that the dietary exposure to low levels of DON in food targets the colon inducing a health-threatening breakdown of the colonic barrier, highlighting oral exposure to DON as a potential risk factor in triggering IBD.

SETD8 involved in the progression of inflammatory bowel disease via epigenetically regulating p62 expression

BACKGROUND AND AIM

Epigenetic modification is an important part of the pathogenesis of inflammatory bowel disease (IBD). Some studies proved that p62 was involved in inflammatory response and upregulated in IBD patients, and histone modification plays an important role in regulating p62 expression. SETD8, a histone H4K20 methyltransferase, has been reported downregulated in some inflammatory diseases. Here, we investigated the role of SETD8 in the development of IBD and its underlying mechanisms.

METHODS

An inflammatory cell model was established to elucidate whether SETD8 involved in inflammatory response in macrophages. Three percent dextran sodium sulfate-induced colitis murine model injection with SETD8 inhibitor was used in our study to investigate whether SETD8 inhibition can affect the progress of IBD. The expression of SETD8 and p62 was measured by qRT-PCR and western blot. The mRNA level of inflammatory cytokines was analyzed by qRT-PCR. In addition, chromatin immunoprecipitation-PCR was performed to identify the mechanism by which SETD8 regulates p62.

RESULTS

SETD8 expression obviously decreased in vitro, in vivo models and in IBD patients. In lipopolysaccharide-activated RAW264.7 cells, knockdown of SETD8 significantly increased the mRNA expression of inducible nitric oxide synthase, cyclooxygenase-2, TNF-α, IL-6, IL-1β, and MCP-1. Based on the dataset, we verified that p62 was a target gene of SETD8 and chromatin immunoprecipitation-PCR assay identified that silence of SETD8 distinctly decreases the H4K20me1 enrichment in the promoter of p62. Moreover, silencing of p62 partly reverses the SETD8 inhibition-mediated pro-inflammatory effect in vitro. Finally, SETD8 pharmacological inhibitor (UNC0379) aggravated the disease progression in dextran sodium sulfate-induced murine colitis.

CONCLUSION

Our findings elucidate an epigenetic mechanism by which SETD8 regulates the p62 expression and restrains the inflammatory response in colitis. Our result suggests that targeting SETD8 may be a promising therapy for IBD.

Utilization of physiologically-based pharmacokinetic model to assess disease-mediated therapeutic protein-disease-drug interaction in immune-mediated inflammatory diseases

It is known that interleukin-6 (IL-6) can significantly modulate some key drug-metabolizing enzymes, such as phase I cytochrome P450s (CYPs). In this study, a physiologically-based pharmacokinetic (PBPK) model was developed to assess CYPs mediated therapeutic protein drug interactions (TP-DIs) in patients with immune-mediated inflammatory diseases (IMIDs) with elevated systemic IL-6 levels when treated by anti-IL-6 therapies. Literature data of IL-6 levels in various diseases were incorporated in SimCYP to construct respective virtual patient populations. The modulation effects of systemic IL-6 level and local IL-6 level in the gastrointestinal tract (GI) on CYPs activities were assessed. Upon blockade of the IL-6 signaling pathway by an anti-IL-6 treatment, the area under plasma concentration versus time curves (AUCs) of S-warfarin, omeprazole, and midazolam were predicted to decrease by up to 40%, 42%, and 46%, respectively. In patients with Crohn's disease and ulcerative colitis treated with an anti-IL-6 therapy, the lowering of the elevated IL-6 levels in the local GI tissue were predicted to result in further decreases in AUCs of those CYP substrates. The propensity of TP-DIs under comorbidity conditions, such as in patients with cancer with IMID, were also explored. With further validation with relevant clinical data, this PBPK model may provide an in silico way to quantify the magnitude of potential TP-DI in patients with elevated IL-6 levels when an anti-IL-6 therapeutic is used with concomitant small-molecule drugs. This model may be further adapted to evaluate the CYP modulation effect by other therapeutic modalities, which would significantly alter levels of proinflammatory cytokines during the treatment period.

Diving into Inflammation: A Pilot Study Exploring the Dynamics of the Immune-Microbiota Axis in Ileal Tissue Layers of Patients with Crohn's Disease

BACKGROUND AND AIMS

The pathogenesis of Crohn's disease [CD] is still unclear. Disorders in the mucosal immunoregulation and its crosstalk with the microbiota may represent an important component in tissue injury. We aimed to characterize the molecular immune response distribution within the ileal layers and to evaluate the correlated microbiota in pathological/healthy settings comparing first surgery/relapse clinical conditions.

METHODS

We enrolled 12 CD patients. A comprehensive analysis of an ileal mucosa, submucosa and serosa broad-spectrum cytokine panel was performed through a multiplex approach. In addition, ileal microbiota composition was assessed through next generation sequencing.

RESULTS

We observed a distinct profile [of IL1-α, IL-1β, IL-4, IL-8, ICAM-1, E-Selectin, P-Selectin, IP-10, IL 6 and IL 18] across the CD vs healthy ileal layers; and a different distribution of IFN- γ, P-Selectin, IL-27 and IL-21 in first surgery vs relapse patients. In addition, the phylum Tenericutes, the family Ruminococcaceae, and the genera Mesoplasma and Mycoplasma were significantly enriched in the pathological setting. Significant microbiota differences were observed between relapse and first surgery patients regarding the class Bacteroidia, and the genera Prevotella, Flavobacterium, Tepidimonas and Escherichia/Shigella. Finally, the abundance of the genus Mycoplasma was positively correlated with IL-18.

CONCLUSIONS

We describe a dissimilarity of cytokine distribution and microbiota composition within CD and adjacent healthy ileal tissue layers and between first operation and surgical relapse. Our results give potential insight into the dynamics of the gut microbiota-immune axis in CD patients, leading to detection of new biomarkers.

Implications the Role of miR-155 in the Pathogenesis of Autoimmune Diseases

MicroRNAs (miRNAs) are small noncoding conserved RNAs containing 19 to 24 nucleotides that are regulators of post-translational modifications and are involved in the majority of biological processes such as immune homeostasis, T helper cell differentiation, central and peripheral tolerance, and immune cell development. Autoimmune diseases are characterized by immune system dysregulation, which ultimately leads to destructive responses to self-antigens. A large body of literature suggests that autoimmune diseases and immune dysregulation are associated with different miRNA expression changes in the target cells and tissues of adaptive or innate immunity. miR-155 is identified as a critical modulator of immune responses. Recently conducted studies on the expression profile of miR-155 suggest that the altered expression and function of miR-155 can mediate vulnerability to autoimmune diseases and cause significant dysfunction of the immune system.

In vivo evidence: Repression of mucosal immune responses in mice with colon cancer following sustained administration of Streptococcus thermophiles

Probiotics have attracted considerable attention because of their ability to ameliorate disease and prevent cancer. In this study, we examined the immunomodulatory effects of a Streptococcus thermophilus probiotic on the intestinal mucosa azoxymethane-induced colon cancer. Sixty female mice were divided into four groups (n = 15 each). One group of untreated mice was used as a control (C group). Another mouse group was injected with azoxymethane once weekly for 8 weeks to induce colon cancer (CC group). Finally, two groups of mice were continuously treated twice per week from week 2 to 16 with either the Lactobacillus plantarum (Lac CC group) or S. thermophilus (Strep CC group) bacterial strain pre-and post-treatment as performed for the CC group. Remarkably, Tlr2, Ifng, Il4, Il13, Il10, and Tp53 transcription were significantly downregulated in the Strep CC intestinal mucosa group. Additionally, IL2 expression was decreased significantly in the Strep CC mouse serum, whereas TNFα was remarkably elevated compared to that in the CC, Lac CC, and untreated groups. This study suggested that Streptococcus thermophilus did not interrupt or hinder colon cancer development in mice when administered as a prophylactic.

Extensive Histopathological Characterization of Inflamed Bowel in the Dextran Sulfate Sodium Mouse Model with Emphasis on Clinically Relevant Biomarkers and Targets for Drug Development

This study aims to develop a reliable and reproducible inflammatory bowel disease (IBD) murine model based on a careful spatial-temporal histological characterization. Secondary aims included extensive preclinical studies focused on the in situ expression of clinically relevant biomarkers and targets involved in IBD. C57BL/6 female mice were used to establish the IBD model. Colitis was induced by the oral administration of 2% Dextran Sulfate Sodium (DSS) for 5 days, followed by 2, 4 or 9 days of water. Histological analysis was performed by sectioning the whole colon into rings of 5 mm each. Immunohistochemical analyses were performed for molecular targets of interest for monitoring disease activity, treatment response and predicting outcome. Data reported here allowed us to develop an original scoring method useful as a tool for the histological assessment of preclinical models of DSS-induced IBD. Immunohistochemical data showed a significant increase in TNF-α, α4β7, VEGFRII, GR-1, CD25, CD3 and IL-12p40 expression in DSS mice if compared to controls. No difference was observed for IL-17, IL-23R, IL-36R or F480. Knowledge of the spatial-temporal pattern distribution of the pathological lesions of a well-characterized disease model lays the foundation for the study of the tissue expression of meaningful predictive biomarkers, thereby improving translational success rates of preclinical studies for a personalized management of IBD patients.

Inflammatory bowel disease: Therapeutic limitations and prospective of the stem cell therapy

Inflammatory bowel disease (IBD), consisting primarily of ulcerative colitis and Crohn’s disease, is a group of debilitating auto-immune disorders, which also increases the risk of colitis-associated cancer. However, due to the chronic nature of the disease and inconsistent treatment outcomes of current anti-IBD drugs (e.g., approximately 30% non-responders to anti-TNFα agents), and related serious side effects, about half of all IBD patients (in millions) turn to alternative treatment options. In this regard, mucosal healing is gaining acceptance as a measure of disease activity in IBD patients as recent studies have correlated the success of mucosal healing with improved prognosis. However, despite the increasing clinical realization of the significance of the concept of mucosal healing, its regulation and means of therapeutic targeting remain largely unclear. Here, stem-cell therapy, which uses hematopoietic stem cells or mesenchymal stem cells, remains a promising option. Stem cells are the pluripotent cells with ability to differentiate into the epithelial and/or immune-modulatory cells. The over-reaching concept is that the stem cells can migrate to the damaged areas of the intestine to provide curative help in the mucosal healing process. Moreover, by differentiating into the mature intestinal epithelial cells, the stem cells also help in restoring the barrier integrity of the intestinal lining and hence prevent the immunomodulatory induction, the root cause of the IBD. In this article, we elaborate upon the current status of the clinical management of IBD and potential role of the stem cell therapy in improving IBD therapy and patient’s quality of life.

Pediatric Crohn Disease and Multisystem Inflammatory Syndrome in Children (MIS-C) and COVID-19 Treated With Infliximab

Coronavirus disease 2019 (COVID-19) may lead to a severe inflammatory response referred to as a cytokine storm. We describe a case of severe COVID-19 infection in a recently diagnosed pediatric Crohn disease patient successfully treated with tumor necrosis factor-alpha (TNF-α) blockade. The patient presented with 5 days of fever, an erythematous maculopapular facial rash, and abdominal pain without respiratory symptoms. SARS-CoV-2 polymerase chain reaction was positive. Despite inpatient treatment for COVID-19 and a perianal abscess, the patient acutely decompensated, with worsening fever, tachycardia, fluid-refractory hypotension, elevation of liver enzymes, and transformation of the rash into purpura extending from the face to the trunk, upper and lower extremities, including the palmar and plantar surfaces of the hands and feet. Cytokine profile revealed rising levels of interleukin (IL)-6, IL-8, and TNF-α, higher than those described in either inflammatory bowel disease or severe COVID-19 alone. The patient was treated with infliximab for TNF-α blockade to address both moderately to severely active Crohn disease and multisystem inflammatory syndrome in children temporally related to COVID-19. Within hours of infliximab treatment, fever, tachycardia, and hypotension resolved. Cytokine profile improved with normalization of TNF-α, a decrease in IL-6, and IL-8 concentrations. This case supports a role for blockade of TNF-α in the treatment of COVID-19 inflammatory cascade. The role of anti-TNF agents in patients with multisystem inflammatory syndrome in children temporally related to COVID-19 requires further investigation.

Potent Inhibitory Effect of BJ-3105, a 6-Alkoxypyridin-3-ol Derivative, on Murine Colitis Is Mediated by Activating AMPK and Inhibiting NOX

Inflammatory bowel disease (IBD) is a chronic relapsing inflammation in the gastrointestinal tract. Biological therapeutics and orally available small molecules like tofacitinib (a JAK inhibitor) have been developed to treat IBD, but half of the patients treated with these drugs fail to achieve sustained remission. In the present study, we compared the therapeutic effects of BJ-3105 (a 6-alkoxypyridin-3-ol derivative) and tofacitinib in IBD. BJ-3105 induced activation of AMP-activated protein kinase (AMPK) in the kinase activity measurement and recovery from cytokine-induced AMPK deactivation in HT-29 human colonic epithelial cells. Similar to tofacitinib and D942 (an AMPK activator), BJ-3105 inhibited IL-6-induced JAK2/STAT3 phosphorylation and TNF-α-stimulated activation of IKK/NF-κB, and consequently, stimulus-induced upregulations of inflammatory cytokines and inflammasome components. In addition, unlike tofacitinib or D942, BJ-3105 inhibited NADPH oxidase (NOX) activation and consequent superoxide production induced by activators (mevalonate and geranylgeranyl pyrophosphate) of the NOX cytosolic component Rac. In mice, oral administration with BJ-3105 ameliorated dextran sulfate sodium (DSS)-induced colitis and azoxymethane/DSS-induced colitis-associated tumor formation (CAT) much more potently than that with tofacitinib. Moreover, BJ-3105 suppressed the more severe form of colitis and CAT formation in mice with AMPK knocked-out in macrophages (AMPKα^fl/fl-Lyz2-Cre mice) with much greater efficacy than tofacitinib. Taken together, our findings suggest BJ-3105, which exerted a much better anti-colitis effect than tofacitinib through AMPK activation and NOX inhibition, is a promising candidate for the treatment of IBD.

Effects of Tumor Necrosis Factor Alpha Inhibitors on Lymph Node and Ileocecal Mucosa-Associated Lymphoid Tissue Architecture in Patients With Inflammatory Bowel Disease

BACKGROUND

Antitumor necrosis alpha (TNFα) therapy is often used in the management of patients with inflammatory bowel disease (IBD) and may have effects on lymphoid tissue architecture and function. The goal of our study was to characterize the effects of TNFα inhibitors on mesenteric lymph node and mucosa-associated lymphoid tissue in patients with IBD.

METHODS

We examined lymphoid tissue morphology in IBD patients treated with TNFα inhibitors compared to untreated controls. Intestinal resections from 19 patients (10 anti-TNFα treated and 9 controls) were reviewed. Immunohistochemistry for CD21, CD20, and CD3 was performed on ileocecal valve lymphoid tissue and mesenteric lymph nodes from the resection specimens to assess follicular architecture.

RESULTS

Relative to control groups, TNFα-treated groups showed less preserved germinal center architecture, evidenced by lower overall semiquantitative scores for follicular architecture. Likewise, the percentage of secondary follicles to total follicles was decreased in patients treated with TNFα blockade.

CONCLUSIONS

Our results suggest that TNFα inhibitors may play a role in disruption of lymphoid germinal center architecture in patients with IBD. Awareness of this disrupted lymphoid morphology when examining histologic sections from patients with IBD treated with TNFα inhibitors may prevent unnecessary studies to exclude a lymphoproliferative disorder.

Allergic and Immunologic Perspectives of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic immune-mediated inflammatory condition primarily involving the gastrointestinal tract. It includes Crohn's disease (CD), ulcerative colitis (UC), and a less common phenotype-indeterminate colitis. It is thought to result from a complex interplay of environmental, microbial, and host factors including genetic factors, although the exact mechanism is not known. Dietary factors have been shown to play a role in the pathogenesis of IBD and can potentially alter the intestinal microbiota as well as disrupt the immune function in the gut. CD is characterized by transmural inflammation, sometimes associated with granulomatous lesions, and involves the entire gastrointestinal tract but often spares the rectum. UC is characterized by mucosal inflammation typically confined to the colon and rectum. Although IBD is mostly seen in western world, recent data suggests that the incidence and prevalence are increasing worldwide. Enteral nutrition has been shown to be effective in inducing remission in pediatric population with CD; however, there is mixed data in adult population. Nutritional deficiencies such as vitamin D and zinc deficiency are often noted in IBD patients. Several extraintestinal manifestations are noted in patients with IBD. Some of them parallel with the disease activity and others are independent of the disease course. Assessment of IBD disease activity clinically, radiologically, if indicated, biochemically and endoscopically is important to guide therapy in IBD. To ensure comprehensive care, it is important to assess associated conditions such as nutritional and psychological well-being, as well as age appropriate health maintenance status prior to starting treatment for IBD. Several biologic agents including anti-tumor necrosis factor alpha (anti-TNF-α) drugs, anti-integrins, and antibodies to the p40 subunit of IL12/23 are approved for induction and maintenance of remission of IBD. Steroids are also often used for induction. Anti-metabolites and thiopurines are also useful either as monotherapy or in combination regimens. Potential side effects of anti-TNF-α drugs such as serious infections, malignancy, worsening of heart failure, and infusion-related reactions should be considered prior to starting these drugs. Anti-TNF-α drugs with or without immunomodulators (azathioprine, 6-mercaptopurine, methotrexate) are often used for the induction and maintenance of remission. Treating to target of endoscopic and clinical remission provides the best long-term outcomes. Our knowledge and understanding of IBD has grown significantly. However, there are several unanswered questions on pathogenesis, disease behavior, and drivers of inflammation in various patient subgroups which require further research.

Neonatal Injury Increases Gut Permeability by Epigenetically Suppressing E-Cadherin in Adulthood

Altered intestinal epithelial integrity is an important susceptibility trait in inflammatory bowel disease (IBD), and early life stressors are reported to contribute to this disease susceptibility in adulthood. To identify disease mechanisms associated with early-life trauma that exacerbate IBD in adulthood, we used a "double-hit" neonatal inflammation (NI) and adult inflammation (AI) model that exhibits more severe mucosal injury in the colon later in life. In this study, we explore the underlying mechanisms of this aggravated injury. In rats exposed to both NI and AI, we found sustained increases in colonic permeability accompanied by significantly attenuated expression of the epithelial junction protein E-cadherin. Quantitative RT-PCR revealed a decreased Cdh1 (gene of E-cadherin) mRNA expression in NI + AI rats compared with NI or AI rats. Next, we performed microRNA microarrays to identify potential regulators of E-cadherin in NI + AI rats. We confirmed the overexpression of miR-155, a predicted regulator of E-cadherin, and selected it for further analysis based on reported significance in human IBD. Using ingenuity pathway analysis software, the targets and related canonical pathway of miR-155 were analyzed. Mechanistic studies identified histone hyperacetylation at the Mir155 promoter in NI + AI rats, concomitant with elevated RNA polymerase II binding. In vitro, E-cadherin knockdown markedly increased epithelial cell permeability, as did overexpression of miR-155 mimics, which significantly suppressed E-cadherin protein. In vivo, NI + AI colonic permeability was significantly reversed with administration of miR-155 inhibitor rectally. Our collective findings indicate that early-life inflammatory stressors trigger a significant and sustained epithelial injury by suppressing E-cadherin through epigenetic mechanisms.

Evaluation of cytokine levels as putative biomarkers to predict the pharmacological response to biologic therapy in inflammatory bowel diseases

Cytokines play a central role in the pathogenesis of inflammatory bowel diseases. For this reason, the vast majority of biological therapies are aimed to block pro-inflammatory cytokines or their receptors. Although these drugs have modified the course of the disease due to their efficacy, a high rate of non-response or loss of response over time is still an important issue for clinicians. In this perspective, many studies have been conducted in recent years to individuate a reliable biomarker of therapeutic response. In this review, we discuss the role of cytokines involved in the pathogenesis and in the therapy of inflammatory bowel diseases, and their putative use as pharmacological biomarkers of therapy responsiveness.

Efficacy and safety of endoscopic balloon dilation in inflammatory bowel disease: results of the large multicenter study of the ENEIDA registry

BACKGROUND

There is no information regarding the outcome of Crohn's disease (CD) patients treated with endoscopic balloon dilation (EBD) in non-referral hospitals, nor on the efficacy of EBD in ulcerative colitis (UC). We report herein the results of the largest series published to date.

AIM

To assess the efficacy and safety of EBD for inflammatory bowel disease (IBD) stenosis performed in 19 hospitals with different levels of complexity and to determine factors related to therapeutic success.

METHODS

We identified IBD patients undergoing EBD in the ENEIDA database. Efficacy of EBD was compared between CD and UC and between secondary and tertiary hospitals. Predictive factors of therapeutic success were assessed with multivariate analysis.

RESULTS

Four-hundred dilations (41.2% anastomotic) were performed in 187 IBD patients (13 UC/Indeterminate colitis). Technical and therapeutic success per dilation was achieved in 79.5% and 55.3%, respectively. Therapeutic success per patient was achieved in 78.1% of cases (median follow-up: 40 months) with 49.7% requiring more than one dilation. No differences related to either diagnosis or hospital complexity was found. Technical success [OR 4.12 (95%CI 2.4-7.1)] and not receiving anti-TNF at the time of dilation [OR 1.7 (95% CI 1.1-2.6)] were independently related to therapeutic success per dilation. A stricture length ≤ 2 cm [HR 2.43 (95% CI 1.11-5.31)] was a predictive factor of long-term success per patient. The rate of major complications was 1.3%.

CONCLUSIONS

EBD can be performed with similar efficacy and safety in hospitals with differing levels of complexity and it might be a suitable treatment for UC with short stenosis. To achieve a technical success and the short length of the stenosis seem to be critical for long-term therapeutic success.

L-Fucose ameliorates DSS-induced acute colitis via inhibiting macrophage M1 polarization and inhibiting NLRP3 inflammasome and NF-kB activation

Previous studies reported that L-fucose had anti-inflammatory effects in respiratory and cutaneous system. However, the effect of L-fucose on colitis and the underlying mechanism is poorly understood. We studied the anti-inflammatory effects of L-fucose on Dextran sulfate sodium (DSS)-induced acute colitis in vivo and on LPS/ATP-induced bone marrow derived macrophages (BMDMs) damage in vitro. Our results show that L-fucose significantly alleviated weight loss and disease activity index (DAI) scores in colitis and reduced the infiltration of macrophages and neutrophils. In addition, L-fucose can inhibit macrophage M1 polarization, inactivate the NLRP3 inflammasome and reduce the release of TNFα, IL1β, IL6 pro-inflammatory cytokines. In vitro studies showed that L-fucose ameliorated cell damage resulting from the administration of LPS with ATP in BMDMs, inhibited NLRP3 inflammasome activation and reduced the release of corresponding pro-inflammatory cytokines. Finally, L-fucose can inhibit the expression of p-NF-kB in vivo and in vitro. Overall, our results show that L-fucose can attenuate colitis by inhibiting macrophage M1 polarization, inhibiting NLRP3 inflammasome and NF-kB activation, and down-regulation of pro-inflammatory cytokines.

Metaproteomics of fecal samples of Crohn's disease and Ulcerative Colitis

Crohn's Disease (CD) and Ulcerative Colitis (UC) are chronic inflammatory bowel diseases (IBD) of the gastrointestinal tract. This study used non-invasive LC-MS/MS to find disease specific microbial and human proteins which might be used later for an easier diagnosis. Therefore, 17 healthy controls, 11 CD patients and 14 UC patients but also 13 Irritable Bowel Disease (IBS) patients, 8 Colon Adenoma (CA) patients, and 8 Gastric Carcinoma (GCA) patients were investigated. The proteins were extracted from the fecal samples with liquid phenol in a ball mill. Subsequently, the proteins were digested tryptically to peptides and analyzed by an Orbitrap LC-MS/MS. For protein identification and interpretation of taxonomic and functional results, the MetaProteomeAnalyzer software was used. Cluster analysis and non-parametric test (analysis of similarities) separated healthy controls from patients with CD and UC as well as from patients with GCA. Among others, CD and UC correlated with an increase of neutrophil extracellular traps and immune globulins G (IgG). In addition, a decrease of human IgA and the transcriptional regulatory protein RprY from Bacillus fragilis was found for CD and UC. A specific marker in feces for CD was an increased amount of the human enzyme sucrose-isomaltase. SIGNIFICANCE: Crohn's Disease and Ulcerative Colitis are chronic inflammatory diseases of the gastrointestinal tract, whose diagnosis required comprehensive medical examinations including colonoscopy. The impact of the microbial communities in the gut on the pathogenesis of these diseases is poorly understood. Therefore, this study investigated the impact of gut microbiome on these diseases by a metaproteome approach, revealing several disease specific marker proteins. Overall, this indicated that fecal metaproteomics has the potential to be useful as non-invasive tool for a better and easier diagnosis of both diseases.

Tumour Necrosis Factor Alpha in Intestinal Homeostasis and Gut Related Diseases

The intestinal epithelium constitutes an indispensable single-layered barrier to protect the body from invading pathogens, antigens or toxins. At the same time, beneficial nutrients and water have to be absorbed by the epithelium. To prevent development of intestinal inflammation or tumour formation, intestinal homeostasis has to be tightly controlled and therefore a strict balance between cell death and proliferation has to be maintained. The proinflammatory cytokine tumour necrosis factor alpha (TNFα) was shown to play a striking role for the regulation of this balance in the gut. Depending on the cellular conditions, on the one hand TNFα is able to mediate cell survival by activating NFκB signalling. On the other hand, TNFα might trigger cell death, in particular caspase-dependent apoptosis but also caspase-independent programmed necrosis. By regulating these cell death and survival mechanisms, TNFα exerts a variety of beneficial functions in the intestine. However, TNFα signalling is also supposed to play a critical role for the pathogenesis of inflammatory bowel disease (IBD), infectious diseases, intestinal wound healing and tumour formation. Here we review the literature about the physiological and pathophysiological role of TNFα signalling for the maintenance of intestinal homeostasis and the benefits and difficulties of anti-TNFα treatment during IBD.

Intestinal Organoids as a Novel Complementary Model to Dissect Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs) include colitis ulcerosa and Crohn's disease, besides the rare microscopic colitis. Both diseases show a long-lasting, relapsing-remitting, or even chronic active course with tremendous impact on quality of life. IBDs frequently cause disability, surgical interventions, and high costs; as in other autoimmune diseases, their prevalent occurrence at an early phase of life raises the burden on health care systems. Unfortunately, our understanding of the pathogenesis is still incomplete and treatment therefore largely focuses on suppressing the resulting excessive inflammation. One obstacle for deciphering the causative processes is the scarcity of models that parallel the development of the disease, since intestinal inflammation is mostly induced artificially; moreover, the intestinal epithelium, which strongly contributes to IBD pathogenesis, is difficult to assess. Recently, the development of intestinal epithelial organoids has overcome many of those problems. Here, we give an overview on the current understanding of the pathogenesis of IBDs with reference to the limitations of previous well-established experimental models. We highlight the advantages and detriments of recent organoid-based experimental setups within the IBD field and suggest possible future applications.

Cellular and Molecular Therapeutic Targets in Inflammatory Bowel Disease-Focusing on Intestinal Barrier Function

The human gut relies on several cellular and molecular mechanisms to allow for an intact and dynamical intestinal barrier. Normally, only small amounts of luminal content pass the mucosa, however, if the control is broken it can lead to enhanced passage, which might damage the mucosa, leading to pathological conditions, such as inflammatory bowel disease (IBD). It is well established that genetic, environmental, and immunological factors all contribute in the pathogenesis of IBD, and a disturbed intestinal barrier function has become a hallmark of the disease. Genetical studies support the involvement of intestinal barrier as several susceptibility genes for IBD encode proteins with key functions in gut barrier and homeostasis. IBD patients are associated with loss in bacterial diversity and shifts in the microbiota, with a possible link to local inflammation. Furthermore, alterations of immune cells and several neuro-immune signaling pathways in the lamina propria have been demonstrated. An inappropriate immune activation might lead to mucosal inflammation, with elevated secretion of pro-inflammatory cytokines that can affect the epithelium and promote a leakier barrier. This review will focus on the main cells and molecular mechanisms in IBD and how these can be targeted in order to improve intestinal barrier function and reduce inflammation.

Genistein induces macrophage polarization and systemic cytokine to ameliorate experimental colitis

Mucosal changes in Crohn’s disease (CD) and ulcerative colitis (UC), two major forms of inflammatory bowel disease (IBD), are characterized by a prominent infiltration of inflammatory cells including lymphocytes, macrophages, T cells and neutrophils. The precise etiology of IBD is unknown but it involves a complex interplay of factors associated with the immune system, environment, host genotype and enteric commensal bacteria. As there is no known safe cure for IBD, natural alternative therapeutic options without side effects are urgently needed. To this end, Soy-based foods, which have been eaten for centuries in Asian countries, have potential benefits, including lowering the incidence of coronary heart disease, atherosclerosis, type-2 diabetes, allergic response, and autoimmune diseases. This study describes the effect of Soy isoflavons 4', 5, 7 Trihydroxyisoflavone (genistein) on dextran sodium sulphate (DSS) induced experimental colitis. The extent and severity of disease was analyzed through body weight, histopathological analysis, cellular immune response, systemic cytokine levels, and inflammation score using a disease activity index. Genistein treatment significantly attenuated DSS-induced colitis severity and resulted in increase in body weight, colon length and reduction in inflammation score. Genistein also skews M1 macrophages towards the M2 phenotype. Further, gen also reduced the systemic cytokine levels as compared to vehicle control. This serves as the first detailed study towards natural soya based product that shows the polarization of M1 towards M2 macrophages, and reduction of systemic cytokine in part to attenuate the colitis symptoms. Thus, our work demonstrates that genistein, a soya compound, may be useful for the treatment of IBD.

Cannabinoid Receptor 2 Functional Variant Contributes to the Risk for Pediatric Inflammatory Bowel Disease

GOALS

We conducted a case-control association analysis to establish the role of a common CB2 functional variant, Q63R, in the susceptibility to inflammatory bowel disease (IBD).

BACKGROUND

Endocannabinoids may limit intestinal inflammation through cannabinoid receptor 1 and/or 2 (CB1, CB2).

STUDY

We genotyped 217 pediatric IBD patients [112 Crohn's disease (CD), 105 ulcerative colitis (UC)] and 600 controls for the CB2-Q63R variant by Taqman assay. Data were collected from clinical records on age at diagnosis, disease activity, duration and location, extraintestinal manifestations, therapy, clinical relapses, and need for surgery.

RESULTS

We found a significant association of the CB2-R63 variant with IBD (allele frequencies, P=0.04; genotype distributions, P=0.0006), in particular with CD (allele frequencies, P=0.002; genotype distributions, P=0.00005) and with UC only for genotype distributions (P=0.03). RR carriers showed an increased risk for developing IBD [odds ratio (OR)=1.82; P=0.0002 for IBD; OR=2.02; P=10 for CD; OR=1.63; P=0.02 for UC at 95% confidence interval]. Upon genotype-phenotype evaluation, RR patients showed an increased frequency of moderate-to-severe disease activity at diagnosis in the case of both CD and UC (P=0.01 and P=0.02, respectively) and also an earlier clinical relapse in UC (P=0.04). In UC, all the clinical features related to the CB2 risk allele were still significantly associated with the variant when analyzed using a multivariate logistic regression model (P=0.001).

CONCLUSIONS

The CB2-Q63R variant contributes to the risk for pediatric IBD, in particular CD. The R63 variant is associated with a more severe phenotype in both UC and CD. Taken together, our data point toward the involvement of the CB2 receptor in the pathogenesis and clinical features of pediatric IBD.

Intestinal granular cells of a cartilaginous fish, thornback ray Raja clavata: Morphological characterization and expression of different molecules

This investigation aims to fill gaps in our understanding of the intestinal immune cells of elasmobranchs. Whole digestive tracts of fifteen thornback ray Raja clavata were provided by a trawl fleet from the Gulf of Asinara (Sardinia, western Mediterranean Sea). Histochemical, immunohistochemical and ultrastructural observations were conducted on the spiral intestine. Three types of granular cells were identified; type I in epithelium, types II and III in lamina propria-submucosa, with each of them containing cytoplasmic granules with different ultrastructural characteristics. Data on size and density of each granular cell type are provided. Immunostaining of intestinal sections showed the reactivity of the granular cells: type I cells were positive for lysozyme, mast cell tryptase and tumor necrosis factor-ɑ based on antibody staining; type III cells were immune-reactive to anti-interleukin 6 antibody, whilst type II cells were negative to all the antibodies used. Comparison of each granular cell type with immune cells of teleosts or mammals and an hypothesis on their nature and function are reported. A potential role for granular cells in intestinal cellular immunity is also discussed with respect to type I and type III cells having similarities to Paneth cells and neutrophils, respectively.

The current therapeutic options for Crohn's disease: from medical therapy to intestinal transplantation

Crohn's disease (CD) has an annual incidence per 100.000 person-year of 20.2 in North America and 12.7 in Europe, and the purpose of this review is to evaluate its medical management, from diagnosis to transplant. Pharmacologic manipulation with nutritional care aims to achieve and maintain remission, but more than half of patients will undergo an intestinal resection, very often repeated over time. They could experience short bowel syndrome (SBS) requiring total parenteral nutrition (TPN). Intestinal transplantation (ITx) represents an alternative in case of irreversible intestinal failure (IF) with life-threatening TPN complications. Patient survival after ITx is 79%, 53% and 43% at 1, 3 and 5 years respectively, with no differences among ITx for other disorders. Areas covered: The research discussed medical therapy with nutritional support, evaluating the role of endoscopy, surgery and transplant in CD. A systematic literature review was conducted using the PubMed search engine up to May 31^th, 2017 without restriction of the language. The decision on paper's eligibility was reached by consensus between the 3 screening authors. Expert commentary: CD treatment is mainly medical, leaving endoscopy and surgery for a complex course. ITx represents a therapeutic option if TPN complications with IF arise.

The Innate and Adaptive Immune System as Targets for Biologic Therapies in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date.

Cytokine production profile in intestinal mucosa of paediatric inflammatory bowel disease

In the recent years, the incidence of inflammatory bowel disease (IBD) has dramatically increased in young subjects, however, the pathogenesis of paediatric IBD is poorly investigated. In this study we aimed to evaluate the cytokine pattern and the phenotype of cytokine producing cells in the intestinal mucosa of paediatric patients affected by Crohn’s disease (CD) or ulcerative colitis (UC) and of non-IBD healthy controls (HC). Cytokine (IL-15, TNF-α, INF-γ) production was analyzed at basal condition and after mitogen stimulation either intracellularly by flow cytometry or in intestinal cell culture supernatants by enzyme-linked immunosorbent assay (ELISA). A higher frequency of enterocytes (EpCam+ cells) was observed in UC patients compared to CD or HC. An expansion of enterocytes producing IL-15 and TNF-α were found in IBD patients compared to HC. A marked expression of IL-15 in the intestinal epithelium of IBD patients was further confirmed by immunohistochemistry. Myeloid dendritic (CD11c+) cells producing TNF-α and INF-γ were increased in IBD biopsies. Unexpectedly, only after a strong mitogen stimulus, as phytohaemagglutinin, the frequency of CD3+ cells producing IFN-γ was increased in IBD compared to control intestinal mucosa. Interestingly, functional studies performed on organ cultures of intestinal biopsies with neutralizing anti-IL-15 monoclonal antibody showed a marked reduction of mononuclear cell activation, proliferation of crypt enterocytes, as well as a reduction of TNF-α release in organ culture supernatants. In conclusion, we found that in the gut mucosa of IBD children both enterocytes and dendritic cells produce proinflammatory cytokines. The over-expression of IL-15 by enterocytes in IBD intestine and the reduced IBD inflammation by IL-15 blockage suggests that this cytokine could be a therapeutic target in IBD.

Protecting Bone Health in Pediatric Rheumatic Diseases: Pharmacological Considerations

Bone health in children with rheumatic conditions may be compromised due to several factors related to the inflammatory disease state, delayed puberty, altered life style, including decreased physical activities, sun avoidance, suboptimal calcium and vitamin D intake, and medical treatments, mainly glucocorticoids and possibly some disease-modifying anti-rheumatic drugs. Low bone density or even fragility fractures could be asymptomatic; therefore, children with diseases of high inflammatory load, such as systemic onset juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, and those requiring chronic glucocorticoids may benefit from routine screening of bone health. Most commonly used assessment tools are laboratory testing including serum 25-OH-vitamin D measurement and bone mineral density measurement by a variety of methods, dual-energy X-ray absorptiometry as the most widely used. Early disease control, use of steroid-sparing medications such as disease-modifying anti-rheumatic drugs and biologics, supplemental vitamin D and calcium, and promotion of weight-bearing physical activities can help optimize bone health. Additional treatment options for osteoporosis such as bisphosphonates are still controversial in children with chronic rheumatic diseases, especially those with decreased bone density without fragility fractures. This article reviews common risk factors leading to compromised bone health in children with chronic rheumatic diseases and discusses the general approach to prevention and treatment of bone fragility.

Crohn's Disease and Ulcerative Colitis Show Unique Cytokine Profiles

Introduction

Networks of cytokines have been implicated in both forms of inflammatory bowel disease (IBD): Crohn’s disease (CD) and ulcerative colitis (UC). While CD has associated with T-helper type 1 (Th1) immune responses, UC shows Th2 patterns. Recent studies reported that the inflamed intestinal regions in both CD and UC are significantly infiltrated with a newly described set of T helper, the Th17 cells. These cells have unique cytokine responses. These findings prompted us to further explore the cytokine profiles of CD and UC with a special focus on the Th2 and Th17 related mediators.

Methods

Cytokine transcripts were compared using real-time polymerase chain reaction (PCR) in both inflamed and non-inflamed mucosal specimens from patients with active CD (n=35) or UC (n=20) and without CD or UC (Control, n=54).

Results

In both CD and UC, interleukin (IL)-12 (p40), IL-18, IL-21 and IL-27 transcript levels were higher than in Control. The highest levels of cytokines were found in the diseased areas of CD and UC with only one exception; IL-12 (p40) in CD was more up-regulated in the non-diseased areas compared to diseased CD and Control specimens. CD samples but not UC specimens showed significant IL-17, IL-23, and IL-32 mRNA expression indicating a trend toward Th17 responses. In UC, however, IL-5, IL-13, IL-15 and IL-33 mRNA levels were significantly increased when compared to both CD and Control.

Conclusions

The unique patterns of cytokine networks can help us to better understand the differential expression of their characteristic pathophysiology. In addition, the pharmacological regulation of these small molecules may hold promise to more effective and personalized therapies.

Impairment of Small Intestinal Function in Ulcerative Colitis: Role of Enteric Innervation

Small intestinal dysfunction has been described in patients with ulcerative colitis and in experimental animal models of colitis. This is demonstrated by a decrease in fluid, electrolyte, amino acid, fat and carbohydrate absorption as well as by deranged intestinal motility. Histopathological changes in the small intestines in colitis have not been consistently demonstrated, but there is evidence of structural and biochemical alterations as shown by increased intestinal permeability and a decrease in the expression of multiple brush border membrane enzymes such as disaccharidases and aminopetidases, in both humans and experimental animals. The pathophysiology of this dysfunction has not been elucidated, but it is thought to include alterations in neural circuitry such as increased neuronal excitability, neuronal damage and changes of neuropeptidergic innervation and receptors as well as an increase in local production of pro-inflammatory cytokines and alterations in the production of some neurohumoral mediators. In the following, we provide an update on the advancement of clinical and scientific contributions to elucidate the underlying mechanisms of the alteration of the functions of apparently intact small intestinal segments, induced by ulcerative colitis.

Fatty acid amide hydrolase (FAAH) blockade ameliorates experimental colitis by altering microRNA expression and suppressing inflammation

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), which is thought to result from immune-mediated inflammatory disorders, leads to high morbidity and health care cost. Fatty acid amide hydrolase (FAAH) is an enzyme crucially involved in the modulation of intestinal physiology through anandamide (AEA) and other endocannabinoids. Here we examined the effects of an FAAH inhibitor (FAAH-II), on dextran sodium sulphate (DSS)-induced experimental colitis in mice. Treatments with FAAH-II improved overall clinical scores by reversing weight loss and colitis-associated pathogenesis. The frequencies of activated CD4⁺ T cells in spleens, mesenteric lymph nodes (MLNs), Peyer's patches (PPs), and colon lamina propiria (LP) were reduced by FAAH inhibition. Similarly, the frequencies of macrophages, neutrophils, natural killer (NK), and NKT cells in the PPs and LP of mice with colitis declined after FAAH blockade, as did concentrations of systemic and colon inflammatory cytokines. Microarray analysis showed that 26 miRNAs from MLNs and 217 from PPs had a 1.5-fold greater difference in expression after FAAH inhibition. Among them, 8 miRNAs were determined by reverse-transcription polymerase chain reaction (RT-PCR) analysis to have anti-inflammatory properties. Pathway analysis demonstrated that differentially regulated miRNAs target mRNA associated with inflammation. Thus, FAAH-II ameliorates experimental colitis by reducing not only the number of activated T cells but also the frequency of macrophages, neutrophils, and NK/NKT cell, as well as inflammatory miRNAs and cytokine at effector sites in the colon. These studies demonstrate for the first time that FAAH-II inhibitor may suppress colitis through regulation of pro-inflammatory miRNAs expression.

Involvement of Activated Cdc42 Kinase1 in Colitis and Colorectal Neoplasms

BACKGROUND Activated Cdc42 kinase1 (ACK1) is a non-receptor tyrosine kinase which is critical for cell survival, proliferation, and migration. Genomic amplification of ACK1 has been reported in multiple human cancers. We aimed to investigate ACK1 protein expression in colorectal mucosa with inflammation and neoplasm, and to evaluate its correlation with disease activity and severity. MATERIAL AND METHODS A total of 250 individuals who underwent total colonoscopy were collected randomly from January 2007 to May 2013 in Nanfang Hospital, Guangzhou, China. Colorectal mucosal biopsy specimens were obtained by endoscopy from 78 patients with ulcerative colitis (UC), 22 with Crohn's disease (CD), 20 with infectious colitis, 26 with non-IBD and noninfectious colitis, 16 with sporadic adenomas, 4 with dysplasia-associated lesions or masses, 10 with sporadic colorectal cancer (CRC), 4 with UC-related CRC, 10 with hyperplastic polyps, and 60 without colonic abnormalities. ACK1 protein levels were determined immunohistochemically. The correlations of ACK1 expression with disease activity and severity were also evaluated. RESULTS Significantly increased ACK1 expression was observed in epithelial cells of colorectal mucosa with inflammation and dysplasia compared to controls (P<0.05). ACK1 expression correlated with clinical activity in IBD (χ²=4.57, P=0.033 for UC; χ²=5.68, P=0.017 for CD), as well as grade of dysplasia in preneoplastic lesions (P<0.05). No significant differences in ACK1 expression were found between UC and CD, or between IBD and non-IBD conditions (P>0.05). CONCLUSIONS ACK1 protein is increased extensively in colitis and colorectal dysplasia. ACK1 overexpression may play a role in colorectal inflammation and neoplasms.