The global, regional, and national burden of inflammatory bowel disease in 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017

Diet and Nutrition in Pediatric Inflammatory Bowel Diseases

Both genetic and environmental factors are involved in the onset of inflammatory bowel disease (IBD). In particular, diet composition is suspected to significantly contribute to IBD risk. In recent years, major interest has raised about the role of nutrition in disease pathogenesis and course, and many studies have shown a clear link between diet composition and intestinal permeability impairment. Moreover, many IBD-related factors, such as poor dietary intake, nutrients loss and drugs interact with nutritional status, thus paving the way for the development of many therapeutic strategies in which nutrition represents the cornerstone, either as first-line therapy or as reversing nutritional deficiencies and malnutrition in IBD patients. Exclusive enteral nutrition (EEN) is the most rigorously supported dietary intervention for the treatment of Crohn's Disease (CD), but is burdened by a low tolerability, especially in pediatric patients. Promising alternative regimens are represented by Crohn's Disease Exclusion Diet (CDED), and other elimination diets, whose use is gradually spreading. The aim of the current paper is to provide a comprehensive and updated overview on the latest evidence about the role of nutrition and diet in pediatric IBD, focusing on the different nutritional interventions available for the management of the disease.

Dietary pectic substances enhance gut health by its polycomponent: A review

Pectic substances, one of the cell wall polysaccharides, exist widespread in vegetables and fruits. A surge of recent research has revealed that pectic substances can inhibit gut inflammation and relieve inflammatory bowel disease symptoms. However, physiological functions of pectins are strongly structure dependent. Pectic substances are essentially heteropolysaccharides composed of homogalacturonan and rhamnogalacturonan backbones substituted by various neutral sugar sidechains. Subtle changes in the architecture of pectic substances may remarkably influence the nutritional function of gut microbiota and the host homeostasis of immune system. In this context, developing a structure-function understanding of how pectic substances have an impact on an inflammatory bowel is of primary importance for diet therapy and new drugs. Therefore, the present review has summarized the polycomponent nature of pectic substances, the activities of different pectic polymers, the effects of molecular characteristics and the underlying mechanisms of pectic substances. The immunomodulated property of pectic substances depends on not only the chemical composition but also the physical structure characteristics, such as molecular weight (M_w ) and chain conformation. The potential mechanisms by which pectic substances exert their protective effects are mainly reversing the disordered gut microbiota, regulating immune cells, enhancing barrier function, and inhibiting pathogen adhesion. The manipulation of pectic substances on gut health is sophisticated, and the link between structural specificity of pectins and selective regulation needs further exploration.

STAT3 Signalling via the IL-6ST/gp130 Cytokine Receptor Promotes Epithelial Integrity and Intestinal Barrier Function during DSS-Induced Colitis

The intestinal epithelium provides a barrier against commensal and pathogenic microorganisms. Barrier dysfunction promotes chronic inflammation, which can drive the pathogenesis of inflammatory bowel disease (IBD) and colorectal cancer (CRC). Although the Signal Transducer and Activator of Transcription-3 (STAT3) is overexpressed in both intestinal epithelial cells and immune cells in IBD patients, the role of the interleukin (IL)-6 family of cytokines through the shared IL-6ST/gp130 receptor and its associated STAT3 signalling in intestinal barrier integrity is unclear. We therefore investigated the role of STAT3 in retaining epithelial barrier integrity using dextran sulfate sodium (DSS)-induced colitis in two genetically modified mouse models, to either reduce STAT1/3 activation in response to IL-6 family cytokines with a truncated gp130^∆STAT allele (GP130^∆STAT/+), or by inducing short hairpin-mediated knockdown of Stat3 (shStat3). Here, we show that mice with reduced STAT3 activity are highly susceptible to DSS-induced colitis. Mechanistically, the IL-6/gp130/STAT3 signalling cascade orchestrates intestinal barrier function by modulating cytokine secretion and promoting epithelial integrity to maintain a defence against bacteria. Our study also identifies a crucial role of STAT3 in controlling intestinal permeability through tight junction proteins. Thus, therapeutically targeting the IL-6/gp130/STAT3 signalling axis to promote barrier function may serve as a treatment strategy for IBD patients.

Effect of Cynara cardunculus L. var. altilis (DC) in Inflammatory Bowel Disease

Background: Cynara cardunculus L. var. altilis (DC) is a plant generally associated as an ingredient in the Mediterranean diet. The polyphenols present in this plant provide pharmacological and nutritional properties. C. cardunculus L. has been used throughout animal studies, which demonstrated an anti-inflammatory effect. Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Since there is not a known cure, the research of new possible pharmacological approaches is essential. This study aims to evaluate the effect of an aqueous extract of C. cardunculus L. dry leaves in a 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis model. Methods: CD-1 mice with TNBS-induced colitis received an intraperitoneal (IP) administration of C. cardunculus L. once per day for 4 days. Results: The C. cardunculus L. demonstrated a beneficial effect in this experimental model of IBD with anti-inflammatory action through the reduction of tumor necrosis factor (TNF)-α levels. It also demonstrated a beneficial influence on the extra-intestinal manifestations related to IBD, with the absence of significant side effects of its use. Conclusions: The extract of C. cardunculus L. dry leaves can become an interesting tool for new possible pharmacological approaches in the management of IBD.

Glochidion ellipticum Wight extracts ameliorate dextran sulfate sodium-induced colitis in mice by modulating nuclear factor kappa-light-chain-enhancer of activated B cells signalling pathway

OBJECTIVES

Glochidion ellipticum Wight is a medicinal plant, rich in polyphenols, frequently used by the indigenous communities of Bangladesh and possess with multiple health benefits. It exerts anti-inflammatory and antidiarrheal properties, but the detailed chemical constituents are yet to be elucidated.

METHODS

Glochidion ellipticum extracts were analyzed using ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry and then tested by both lipopolysaccharide (LPS) induced inflammation of Raw 264.7 macrophage cells and dextran sulfate sodium (DSS) induced acute colitis model. Blood serum was taken for fluorescein isothiocyanate-dextran (FITC-dextran) measurement and tissue samples were used to perform histology, RT-PCR and Western blotting.

KEY FINDINGS

The extracts could lower the levels of nitric oxide (NO), reactive oxygen species (ROS) and pro-inflammatory cytokines significantly in LPS induced macrophage cells. The extracts could also reduce disease activity index (DAI) score, restore antioxidants and pro-oxidants and improve macroscopic and microscopic features of colonic tissues in DSS induced mice. Expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in protein level was markedly diminished (up to 51.21% and 71.11%, respectively) in the treatment groups compared to the model group of colitic mice.

CONCLUSIONS

Our findings suggested that G. ellipticum extracts ameliorate DSS colitis via blocking nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway, which make them to be potential candidates for further research against inflammation and colitis.

Caffeic Acid Modulates Processes Associated with Intestinal Inflammation

Caffeic acid is one of the most abundant hydroxycinnamic acids in fruits, vegetables, and beverages. This phenolic compound reaches relevant concentrations in the colon (up to 126 µM) where it could come into contact with the intestinal cells and exert its anti-inflammatory effects. The aim of this investigation was to study the capacity of caffeic acid, at plausible concentrations from an in vivo point of view, to modulate mechanisms related to intestinal inflammation. Consequently, we tested the effects of caffeic acid (50–10 µM) on cyclooxygenase (COX)-2 expression and prostaglandin (PG)E₂, cytokines, and chemokines (IL-8, monocyte chemoattractant protein-1 -MCP-1-, and IL-6) biosynthesis in IL-1β-treated human myofibroblasts of the colon, CCD-18Co. Furthermore, the capacity of caffeic acid to inhibit the angiotensin-converting enzyme (ACE) activity, to hinder advanced glycation end product (AGE) formation, as well as its antioxidant, reducing, and chelating activity were also investigated. Our results showed that (i) caffeic acid targets COX-2 and its product PGE₂ as well as the biosynthesis of IL-8 in the IL-1β-treated cells and (ii) inhibits AGE formation, which could be related to (iii) the high chelating activity exerted. Low anti-ACE, antioxidant, and reducing capacity of caffeic acid was also observed. These effects of caffeic acid expands our knowledge on anti-inflammatory mechanisms against intestinal inflammation.

Do Only Calcium and Vitamin D Matter? Micronutrients in the Diet of Inflammatory Bowel Diseases Patients and the Risk of Osteoporosis

Osteoporosis is one of the most common extraintestinal complications among patients suffering from inflammatory bowel diseases. The role of vitamin D and calcium in the prevention of a decreased bone mineral density is well known, although other nutrients, including micronutrients, are also of extreme importance. Despite the fact that zinc, copper, selenium, iron, cadmium, silicon and fluorine have not been frequently discussed with regard to the prevention of osteoporosis, it is possible that a deficiency or excess of the abovementioned elements may affect bone mineralization. Additionally, the risk of malnutrition, which is common in patients with ulcerative colitis or Crohn's disease, as well as the composition of gut microbiota, may be associated with micronutrients status.

Molecular Imaging of Inflammatory Disease

Inflammatory diseases include a wide variety of highly prevalent conditions with high mortality rates in severe cases ranging from cardiovascular disease, to rheumatoid arthritis, to chronic obstructive pulmonary disease, to graft vs. host disease, to a number of gastrointestinal disorders. Many diseases that are not considered inflammatory per se are associated with varying levels of inflammation. Imaging of the immune system and inflammatory response is of interest as it can give insight into disease progression and severity. Clinical imaging technologies such as computed tomography (CT) and magnetic resonance imaging (MRI) are traditionally limited to the visualization of anatomical information; then, the presence or absence of an inflammatory state must be inferred from the structural abnormalities. Improvement in available contrast agents has made it possible to obtain functional information as well as anatomical. In vivo imaging of inflammation ultimately facilitates an improved accuracy of diagnostics and monitoring of patients to allow for better patient care. Highly specific molecular imaging of inflammatory biomarkers allows for earlier diagnosis to prevent irreversible damage. Advancements in imaging instruments, targeted tracers, and contrast agents represent a rapidly growing area of preclinical research with the hopes of quick translation to the clinic.

Vedolizumab: Potential Mechanisms of Action for Reducing Pathological Inflammation in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), encompassing ulcerative colitis (UC), and Crohn’s disease (CD), are a group of disorders characterized by chronic, relapsing, and remitting, or progressive inflammation along the gastrointestinal tract. IBD is accompanied by massive infiltration of circulating leukocytes into the intestinal mucosa. Leukocytes such as neutrophils, monocytes, and T-cells are recruited to the affected site, exacerbating inflammation and causing tissue damage. Current treatments used to block inflammation in IBD include aminosalicylates, corticosteroids, immunosuppressants, and biologics. The first successful biologic, which revolutionized IBD treatment, targeted the pro-inflammatory cytokine, tumor necrosis factor alpha (TNFα). Infliximab, adalimumab, and other anti-TNF antibodies neutralize TNFα, preventing interactions with its receptors and reducing the inflammatory response. However, up to 40% of people with IBD become unresponsive to anti-TNFα therapy. Thus, more recent biologics have been designed to block leukocyte trafficking to the inflamed intestine by targeting integrins and adhesins. For example, natalizumab targets the α4 chain of integrin heterodimers, α4β1 and α4β7, on leukocytes. However, binding of α4β1 is associated with increased risk for developing progressive multifocal leukoencephalopathy, an often-fatal disease, and thus, it is not used to treat IBD. To target leukocyte infiltration without this life-threatening complication, vedolizumab was developed. Vedolizumab specifically targets the α4β7 integrin and was approved to treat IBD based on the presumption that it would block T-cell recruitment to the intestine. Though vedolizumab is an effective treatment for IBD, some studies suggest that it may not block T-cell recruitment to the intestine and its mechanism(s) of action remain unclear. Vedolizumab may reduce inflammation by blocking recruitment of T-cells, or pro-inflammatory monocytes and dendritic cells to the intestine, and/or vedolizumab may lead to changes in the programming of innate and acquired immune cells dampening down inflammation.

Identification of microRNA-16-5p and microRNA-21-5p in feces as potential noninvasive biomarkers for inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic idiopathic gastrointestinal disease. Increasing evidence suggests that microRNAs (miRNAs) may participate in the pathophysiology of IBD.

METHODS

A miRCURY™ LNA Array and in situ hybridization were employed to screen for differentially expressed miRNAs (DEMs) in fecal specimens from 41 IBD patients (22 ulcerative colitis (UC), 19 Crohn's disease (CD)) and 23 healthy controls (HC). RT-qPCR was performed to confirm the findings. The DEMs target genes and corresponding biological functions were predicted by bioinformatics analysis.

RESULTS

Compared with HC, miR-16-5p in the feces was up-regulated both in UC and CD patients (p < 0.01), while miR-21-5p was up-regulated only in UC patients (p < 0.01). TargetScan 7.2, miRWalk, and miRDB were used to predict 216 public target genes of miR-16-5p and miR-21-5p, and six hub genes (PIK3R1, GRB2, SUZ12, NTRK2, Smurf2, and WWP1) were analyzed using the STRING database and Cytoscape. All the hub genes promote the occurrence and development of IBD-related colorectal cancer.

CONCLUSIONS

The elevated levels of miR-16-5p and miR-21-5p in feces of IBD patients have to guide significance for the noninvasive clinical diagnosis of IBD and have a warning effect on the occurrence of IBD-related colorectal cancer.

Clinical applications of artificial intelligence and machine learning-based methods in inflammatory bowel disease

Our objective was to review and exemplify how selected applications of artificial intelligence (AI) might facilitate and improve inflammatory bowel disease (IBD) care and to identify gaps for future work in this field. IBD is highly complex and associated with significant variation in care and outcomes. The application of AI to IBD has the potential to reduce variation in healthcare delivery and improve quality of care. AI refers to the ability of machines to mimic human intelligence. The range of AI's ability to perform tasks that would normally require human intelligence varies from prediction to complex decision-making that more closely resembles human thought. Clinical applications of AI have been applied to study pathogenesis, diagnosis, and patient prognosis in IBD. Despite these advancements, AI in IBD is in its early development and has tremendous potential to transform future care.

In vitro models of intestinal epithelium: Toward bioengineered systems

The intestinal epithelium, the fastest renewing tissue in human, is a complex tissue hosting multiple cell types with a dynamic and multiparametric microenvironment, making it particularly challenging to recreate in vitro. Convergence of recent advances in cellular biology and microfabrication technologies have led to the development of various bioengineered systems to model and study the intestinal epithelium. Theses microfabricated in vitro models may constitute an alternative to current approaches for studying the fundamental mechanisms governing intestinal homeostasis and pathologies, as well as for in vitro drug screening and testing. Herein, we review the recent advances in bioengineered in vitro intestinal models.

Hyptis suaveolens (L.) Poit protects colon from TNBS-induced inflammation via immunomodulatory, antioxidant and anti-proliferative mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

In folk medicine Hyptis suaveolens (Lamiaceae) has been reported to relieve respiratory and gastrointestinal infections, indigestion, cold, pain, fever, cramps, skin diseases, gastric ulcer and inflammatory disorders. This study investigated the effects and the mechanisms of action of Hyptis suaveolens (L.) Poit (Lamiaceae) ethanol extract (Hs-EtOH) and hexane phase (Hs-HexF) against intestinal inflammation.

MATERIAL AND METHODS

Acute and relapse TNBS-induced ulcerative colitis protocols were used to evaluate intestinal anti-inflammatory activity. Damage evaluations, biochemical, histological and immunostaining parameters were determined.

RESULTS

Both extracts decreased macroscopic colonic inflammation and the area of lesion induced by TNBS. Nevertheless, only Hs-HexF was able to reduce colonic wall thickness, edema and diffuse inflammatory cell infiltration and to prevent GSH depletion in the acute model of ulcerative colitis. In the chronic phase with relapse of colonic ulceration, yet again only Hs-HexF significantly attenuated inflammatory parameters and presented a decrease in nitrite/nitrate, MDA, MPO, IL-1-β and TNF-α and increased levels of SOD, CAT, GSH and IL-10. Hs-HexF also significantly reduced positive cells immunostained for PCNA.

CONCLUSION

The data indicate intestinal anti-inflammatory activity for H. suaveolens, due to the participation of the antioxidant system, decreased neutrophil infiltration and cytokine modulation, as well as, owing to regulation of cell proliferation.

Impact of titanium dioxide nanoparticles on intestinal community in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced acute colitis mice and the intervention effect of vitamin E

Titanium dioxide nanoparticles (TiO2-NPs) are widely applied as additives in foods due to their excellent whitening and brightening capability. Although the toxicity and antibacterial activity of TiO2-NPs have been extensively studied, their impact on the gut microbiota in vivo still remains unclear, especially in animals with gastrointestinal disorders. In the present study, healthy mice and TNBS-induced colitis mice were administered with TiO2-NPs (38.3 ± 9.3 nm) orally at a dose of 100 mg per kg bw daily for 10 days to study the impact of TiO2-NPs on the gut microbiota and colitis development. Moreover, the mechanism of TiO2-NPs on the gut microbiota was also discussed when the colitis mice were additionally administered with vitamin E to remove ROS. Changes in the microbiota community structure and gut-associated function prediction were analyzed through bioinformatics. The result showed that the oral administration of TiO2-NPs mitigated colitis symptoms by reducing the DAI and CMDI scores and TNF-α level. Furthermore, 16S rDNA sequencing analysis showed that the structure and function prediction of gut microbiota could be modified in healthy mice and colitis mice after exposure to TiO2-NPs, but the opposite physiological effect occurred since the dominant flora varied in these two groups. Moreover, vitamin E intervention did not change the effects of TiO2-NPs on the microbiota community structure and gut-associated function, which indicates that the mechanism of the biological effects of TiO2-NPs on the gut microbiota may not be associated with their ability to induce the generation of ROS. In summary, our work firstly found that TiO2-NPs could regulate the gut microbiota of colitis mice and participate in the mitigation of TNBS-induced acute colitis, and the capability of TiO2-NPs to induce the generation of ROS inducement did not contribute to this process.

Patient Outcomes Following Emergency Bowel Resection for Inflammatory Bowel Disease and the Impact of Surgical Subspecialisation in the North of England: A Retrospective Cohort Study

BACKGROUND

Management of inflammatory bowel disease (IBD) has changed considerably over recent years, which has coincided with increased subspecialisation amongst general surgeons. This study evaluated the demographics and outcomes of patients with IBD undergoing bowel resection and assessed for the potential impact of surgical subspecialisation.

METHODS

Patient demographic, operative and outcome data were collected for patients undergoing a bowel resection secondary to IBD, admitted acutely to NHS trusts in the North of England between 2002 and 2016. The primary outcome of interest was 30-day post-operative mortality, with secondary outcomes: length of stay, stoma and anastomosis rates.

RESULTS

A total of 913 patients were included in the study cohort. A reduction in the number of resections was noted over time (2002-2006: 361 vs. 2012-2016: 262). No change was observed for 30-day mortality over the study period (3.9%, p = 0.233). Length of stay was also unchanged (p = 0.949). Laparoscopic surgery was increasingly utilised (0.6% vs. 17.2%, p < 0.001) in recent years, and by colorectal subspecialists (p = 0.003). More patients were managed by a colorectal consultant latterly (2002-2006: 45.4% vs. 2012-2016: 63.7%, p < 0.001). There was no difference between colorectal and other subspecialists in mortality (p = 0.156), length of stay (p = 0.201), stoma (p = 0.629) or anastomosis (p = 0.659) rates, including following multivariable adjustment.

CONCLUSION

The study demonstrated a significant reduction in the number of resections over time, increased utilisation of a laparoscopic approach and a shift towards the care of IBD surgical patients being by a colorectal subspecialist. However, these changes do not correspond with improved surgical outcomes.

Drug Disposition in the Lower Gastrointestinal Tract: Targeting and Monitoring

The increasing prevalence of colonic diseases calls for a better understanding of the various colonic drug absorption barriers of colon-targeted formulations, and for reliable in vitro tools that accurately predict local drug disposition. In vivo relevant incubation conditions have been shown to better capture the composition of the limited colonic fluid and have resulted in relevant degradation and dissolution kinetics of drugs and formulations. Furthermore, drug hurdles such as efflux transporters and metabolising enzymes, and the presence of mucus and microbiome are slowly integrated into drug stability- and permeation assays. Traditionally, the well characterized Caco-2 cell line and the Ussing chamber technique are used to assess the absorption characteristics of small drug molecules. Recently, various stem cell-derived intestinal systems have emerged, closely mimicking epithelial physiology. Models that can assess microbiome-mediated drug metabolism or enable coculturing of gut microbiome with epithelial cells are also increasingly explored. Here we provide a comprehensive overview of the colonic physiology in relation to drug absorption, and review colon-targeting formulation strategies and in vitro tools to characterize colonic drug disposition.

Application of Polymeric Nano-Materials in Management of Inflammatory Bowel Disease

Inflammatory Bowel Disease (IBD) is an umbrella term used to describe disorders that involve Crohn's disease (CD), ulcerative colitis (UC) and pouchitis. The disease occurrence is more prevalent in the working group population which not only hampers the well being of an individual but also has negative economical impact on society. The current drug regime used therapy is very costly owing to the chronic nature of the disease leading to several side effects. The condition gets more aggravated due to the lower concentration of drug at the desired site. Therefore, in the present scenario, a therapy is needed which can maximize efficacy, adhere to quality of life, minimize toxicity and doses, be helpful in maintaining and stimulating physical growth of mucosa with minimum disease complications. In this aspect, nanotechnology intervention is one promising field as it can act as a carrier to reduce toxicity, doses and frequency which in turn help in faster recovery. Moreover, nanomedicine and nanodiagnostic techniques will further open a new window for treatment in understanding pathogenesis along with better diagnosis which is poorly understood till now. Therefore the present review is more focused on recent advancements in IBD in the application of nanotechnology.

Inflammatory Bowel Disease: New Insights into the Interplay between Environmental Factors and PPARγ

The pathophysiological processes of inflammatory bowel diseases (IBDs), i.e., Crohn's disease (CD) and ulcerative colitis (UC), are still not completely understood. The exact etiology remains unknown, but it is well established that the pathogenesis of the inflammatory lesions is due to a dysregulation of the gut immune system resulting in over-production of pro-inflammatory cytokines. Increasing evidence underlines the involvement of both environmental and genetic factors. Regarding the environment, the microbiota seems to play a crucial role. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that exert pleiotropic effects on glucose homeostasis, lipid metabolism, inflammatory/immune processes, cell proliferation, and fibrosis. Furthermore, PPARs modulate interactions with several environmental factors, including microbiota. A significantly impaired PPARγ expression was observed in UC patients' colonic epithelial cells, suggesting that the disruption of PPARγ signaling may represent a critical step of the IBD pathogenesis. This paper will focus on the role of PPARγ in the interaction between environmental factors and IBD, and it will analyze the most suitable in vitro and in vivo models available to better study these relationships.

Not All Fibers Are Born Equal; Variable Response to Dietary Fiber Subtypes in IBD

Diet provides a safe and attractive alternative to available treatment options in a variety of diseases; however, research has only just begun to elucidate the role of diet in chronic diseases, such as the inflammatory bowel diseases (IBD). The chronic and highly debilitating IBDs, Crohn disease and ulcerative colitis, are hallmarked by intestinal inflammation, immune dysregulation, and dysbiosis; and evidence supports a role for genetics, microbiota, and the environment, including diet, in disease pathogenesis. This is true especially in children with IBD, where diet-based treatments have shown excellent results. One interesting group of dietary factors that readily links microbiota to gut health is dietary fibers. Fibers are not digested by human cells, but rather fermented by the gut microbes within the bowel. Evidence has been mounting over the last decade in support of the importance of dietary fibers in the maintenance of gut health and in IBD; however, more recent studies highlight the complexity of this interaction and importance of understanding the role of each individual dietary fiber subtype, especially during disease. There are roughly ten subtypes of dietary fibers described to date, categorized as soluble or insoluble, with varying chemical structures, and large differences in their fermentation profiles. Many studies to date have described the benefits of the byproducts of fermentation in healthy individuals and the potential health benefits in select disease models. However, there remains a void in our understanding of how each of these individual fibers affect human health in dysbiotic settings where appropriate fermentation may not be achieved. This review highlights the possibilities for better defining the role of individual dietary fibers for use in regulating inflammation in IBD.

Coumarin Derivatives in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a non-communicable disease characterized by a chronic inflammatory process of the gut and categorized into Crohn’s disease and ulcerative colitis, both currently without definitive pharmacological treatment and cure. The unclear etiology of IBD is a limiting factor for the development of new drugs and explains the high frequency of refractory patients to current drugs, which are also related to various adverse effects, mainly after long-term use. Dissatisfaction with current therapies has promoted an increased interest in new pharmacological approaches using natural products. Coumarins comprise a large class of natural phenolic compounds found in fungi, bacteria, and plants. Coumarin and its derivatives have been reported as antioxidant and anti-inflammatory compounds, potentially useful as complementary therapy of the IBD. These compounds produce protective effects in intestinal inflammation through different mechanisms and signaling pathways, mainly modulating immune and inflammatory responses, and protecting against oxidative stress, a central factor for IBD development. In this review, we described the main coumarin derivatives reported as intestinal anti-inflammatory products and its available pharmacodynamic data that support the protective effects of these products in the acute and subchronic phase of intestinal inflammation.

Titanium Dioxide Presents a Different Profile in Dextran Sodium Sulphate-Induced Experimental Colitis in Mice Lacking the IBD Risk Gene Ptpn2 in Myeloid Cells

Environmental and genetic factors have been demonstrated to contribute to the development of inflammatory bowel disease (IBD). Recent studies suggested that the food additive; titanium dioxide (TiO2) might play a causative role in the disease. Therefore, in the present study we aimed to explore the interaction between the food additive TiO2 and the well-characterized IBD risk gene protein tyrosine phosphatase non-receptor type 2 (Ptpn2) and their role in the development of intestinal inflammation. Dextran sodium sulphate (DSS)-induced acute colitis was performed in mice lacking the expression of Ptpn2 in myeloid cells (Ptpn2LysMCre) or their wild type littermates (Ptpn2fl/fl) and exposed to the microparticle TiO2. The impact of Ptpn2 on TiO2 signalling pathways and TiO2-induced IL-1β and IL-10 levels were studied using bone marrow-derived macrophages (BMDMs). Ptpn2LysMCre exposed to TiO2 exhibited more severe intestinal inflammation than their wild type counterparts. This effect was likely due to the impact of TiO2 on the differentiation of intestinal macrophages, suppressing the number of anti-inflammatory macrophages in Ptpn2 deficient mice. Moreover, we also found that TiO2 was able to induce the secretion of IL-1β via mitogen-activated proteins kinases (MAPKs) and to repress the expression of IL-10 in bone marrow-derived macrophages via MAPK-independent pathways. This is the first evidence of the cooperation between the genetic risk factor Ptpn2 and the environmental factor TiO2 in the regulation of intestinal inflammation. The results presented here suggest that the ingestion of certain industrial compounds should be taken into account, especially in individuals with increased genetic risk.

Enteric Viruses and Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), is a multifactorial disease in which dietary, genetic, immunological, and microbial factors are at play. The role of enteric viruses in IBD remains only partially explored. To date, epidemiological studies have not fully described the role of enteric viruses in inflammatory flare-ups, especially that of human noroviruses and rotaviruses, which are the main causative agents of viral gastroenteritis. Genome-wide association studies have demonstrated the association between IBD, polymorphisms of the FUT2 and FUT3 genes (which drive the synthesis of histo-blood group antigens), and ligands for norovirus and rotavirus in the intestine. The role of autophagy in defensin-deficient Paneth cells and the perturbations of cytokine secretion in T-helper 1 and T-helper 17 inflammatory pathways following enteric virus infections have been demonstrated as well. Enteric virus interactions with commensal bacteria could play a significant role in the modulation of enteric virus infections in IBD. Based on the currently incomplete knowledge of the complex phenomena underlying IBD pathogenesis, future studies using multi-sampling and data integration combined with new techniques such as human intestinal enteroids could help to decipher the role of enteric viruses in IBD.

Administration of neem (Azadirachta indica A. Juss) leaf extract decreases TNF-α and IL-6 expressions in dextran sodium sulfate-induced colitis in rats

Objective:

We aimed to determine the neem leaf extract’s effect on Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-6 (IL-6) expressions in dextran sodium sulfate (DSS)-induced colitis rats.

Materials and Methods:

In the first phase of the study, colitis was induced by DSS administration in the case group and compared to the control group. In the second phase, 84 colitis rats were divided into groups I, II, and III receiving 7.8 mg/day of mesalazine, 100 mg/200 gm body weight, and 200 mg/200 gm body weight neem leaf extract, respectively.

Results:

TNF-α and IL-6 expressions were significantly increased in the case group compared to the control group. TNF-α and IL-6 expressions were decreasing in all groups receiving treatment. Group III showed an earlier decrease compared to group II. TNF-α and IL-6 expressions in group III were comparable with group I since the second week. This condition was observed in the 4th week between group II and group I.

Conclusion:

It can be concluded that neem leaf extract decreased the expression of TNF-α and IL-6 in DSS-induced colitis.

Impact of Body Mass Index on the Development of Inflammatory Bowel Disease: A Systematic Review and Dose-Response Analysis of 15.6 Million Participants

BACKGROUND

A growing trove of literature describes the effect of malnutrition and underweight on the incidence of inflammatory bowel disease (IBD). However, evidence regarding the association between underweight or obesity and IBD is limited. The study aimed to assess the association of body mass index (BMI) with a risk of IBD (Crohn's disease (CD) and ulcerative colitis (U.C.)) incidence.

METHODS

We systematically searched PubMed/Medline, Cochrane, Web of Science, and Scopus for observational studies assessing the association between BMI and IBD that were published up to 30 June 2020. We estimated pooled hazard ratios (HR) with corresponding 95% confidence intervals (CI). Random effect dose-response meta-analysis was performed using the variance weighted least-squares regression (VWLS) models to identify non-linear associations.

RESULTS

A total of ten studies involving 15.6 million individuals and 23,371 cases of IBD were included. Overall, obesity was associated with an increased IBD risk (HR: 1.20, 95% CI: 1.08-1.34, I 2 = 0%). Compared to normal weight, underweight (BMI < 18.5 kg/m2) and obesity (BMI ≥ 30 kg/m2) were associated with a higher risk of CD, and there was no difference in the risk of U.C. among those with BMI < 18.5 kg/m2 and BMI ≥ 30 kg/m2. There was a significant non-linear association between being underweight and obesity and the risk of development of CD (Coef1 = -0.0902, p 1 < 0.001 Coef2 = 0.0713, p 2 < 0.001).

CONCLUSIONS

Obesity increases the risk of IBD development. Underweight and obesity are independently associated with an increased risk of CD, yet there is no evident association between BMI and the risk of U.C. Further studies are needed to clarify the underlying mechanism for these findings, particularly in CD.

Inflammatory bowel disease is associated with higher dementia risk: a nationwide longitudinal study

OBJECTIVE

Increasing evidence supports reciprocal communication between the enteric and the central nervous system in disease, termed the 'gut-brain axis'. Recent findings suggest a connection between IBD and development of Parkinson's disease. The role of IBD in dementia, another insidious neurodegenerative disorder, has not been explored.

DESIGN

Using the Taiwanese National Health Insurance Research Database, we performed comparative analysis of 1742 patients with IBD ≥45 years old against 17 420 controls to assess dementia risk following IBD diagnosis. Controls were matched on bases of sex, access to healthcare, income and dementia-related comorbidities. All individuals were followed for dementia diagnosis for up to 16 years. Subanalyses included the relationship between sex, ulcerative colitis (UC) and Crohn's disease (CD), and dementia risk.

RESULTS

Overall incidence of dementia among patients with IBD was significantly elevated (5.5% vs 1.4% among controls). Patients with IBD were diagnosed with dementia at 76.24 years old on average, compared with 83.45 among controls. The HR of developing dementia among patients with IBD was 2.54 (95% CI 1.91 to 3.37). Among dementia types, the risk of developing Alzheimer's dementia demonstrated the greatest increase. Dementia risk did not differ between sex differences nor UC versus CD.

CONCLUSION

This population-based cohort study demonstrates significant association between IBD and subsequent development of dementia. Dementia was diagnosed at an earlier age among patients with IBD, and disease risk appeared to increase with IBD chronicity. These findings highlight the need for future research to elucidate the relationship between IBD and dementia.

ROS-responsive microcapsule assembly from Turkish galls for ulcerative colitis therapy

Schematic representation of the preparation process of GTA–FeIII MCPs (B) and the ROS-responsive drug release at inflammation sites (A).

Resilience as a Mediator of the Association Between Perceived Stigma and Quality of Life Among People With Inflammatory Bowel Disease

Background: Improving Quality of Life (QOL) is an essential objective in the management of inflammatory bowel disease. An accumulating body of research has been conducted to explore the association between perceived stigma and QOL among patients with chronic illness. Still, underlying mechanisms behind this pathway have not been thoroughly examined. Objective: To investigate (a) the effect of perceived stigma on QOL among patients with inflammatory bowel disease; and (b) the mediating role of resilience in the association between perceived stigma and QOL. Methods: This cross-sectional study included a convenient sample of patients diagnosed with inflammatory bowel disease from four tertiary hospitals in Jiangsu Province, China. Patients completed the Perceived Stigma Scale in Inflammatory Bowel Disease (PSS-IBD), the Resilience Scale for Patients with Inflammatory Bowel Disease (RS-IBD), and the Inflammatory Bowel Disease Questionnaire (IBDQ). A bootstrapping analysis was implemented using the SPSS macro PROCESS. Results: A total of 311 patients with Cohn's disease and ulcerative colitis participated in this study, and 57.6% were men. The mean disease duration was 3.51 ± 1.04 years. Approximately 40% of the sample exceeded the criterion score for moderate stigma. Patients who perceived moderate or severe stigma reported lower QOL compared with those with mild stigma. After controlling for sociodemographic and clinical variables, we observed that perceived stigma was negatively associated with resilience. Moreover, resilience was found to mediate the relationship between perceived stigma and all aspects of QOL. Conclusions: These findings suggested that QOL of patients with inflammatory bowel disease was associated with perceived stigma and resilience and identified the mediating effects of resilience in the relationship between perceived stigma and QOL. Furthermore, this suggests that integrating intervention techniques to target resilience into the QOL improvement program of individuals with perceived stigma is possible.

Multidimensional Assessment of Interoceptive Abilities, Emotion Processing and the Role of Early Life Stress in Inflammatory Bowel Diseases

Perception of internal bodily sensations includes three dissociable processes: interoceptive accuracy, interoceptive sensibility, and interoceptive awareness. Interoceptive abilities play a crucial role in emotion processing and impairments of these processes have been reported in several psychiatric disorders. Studies investigating interoceptive abilities and their role in emotional experience in individuals with somatic disorders such as inflammatory bowel diseases (IBD) are sparse. Recent findings suggested an association between adverse childhood experiences (ACE) and the development of gastrointestinal disorders. The aim of the current study was to investigate the associations between the different dimensions of interoception and emotional processing in IBD while taking ACE into account. We recruited IBD patients in clinical remission (n = 35) and 35 healthy control participants (HC) matched for age, education and IQ. Interoception was measured as a three-dimensional construct. Interoceptive accuracy was assessed with the heartbeat tracking task and interoceptive sensibility with a self-report measure (Multidimensional Assessment of Interoceptive Awareness questionnaire). Emotional processing was measured using an experimental task, where participants were asked to rate the subjectively perceived valence and arousal when presented with positive, neutral and negative visual stimuli. IBD patients significantly differed in two interoceptive sensibility domains, Emotional awareness and Not-distracting. Patients reported greater awareness of the connection between bodily sensations and emotional states, while showing a stronger tendency to use distraction from unpleasant sensations compared with HC. Higher emotional awareness was linked to higher perceived intensity and arousal of negative stimuli. The strength of this relation was dependent on the severity of ACE, with severer traumatization being associated with a stronger association between emotional awareness and perceived valence and arousal. Our findings suggest that it is the subjective component of interoception, especially the one assessing interoceptive abilities within the scope of emotional experience, which affects emotional processing in IBD. This is the first study providing evidence that IBD patients did not differ in their perception of visceral signals per se but only in the subjective ability to attribute certain physical sensations to physiological manifestations of emotions. Our findings support the hypothesis that ACE affect the association between interoception and emotional processing.

Iron Formulations for the Treatment of Iron Deficiency Anemia in Patients with Inflammatory Bowel Disease: A Cost-Effectiveness Analysis in Switzerland

INTRODUCTION

Iron deficiency anemia (IDA) is a common complication of inflammatory bowel disease (IBD) and can result in reduced quality of life and increased healthcare costs. IDA is treated with iron supplementation, either with oral iron therapy (OI) or intravenous iron formulations, including ferric carboxymaltose (FCM), iron isomaltoside 1000 (IIM), and iron sucrose (IS). This analysis compared the cost-effectiveness of FCM versus IIM, IS, and OI in terms of additional cost per additional responder in Switzerland.

METHODS

A health economic model was developed to assess the additional cost per additional responder, defined as normalization or an increase of at least 2 g/dL in hemoglobin levels, for FCM versus IIM, IS, and OI. To date, no single head-to-head trial comparing all therapies is available, and therefore relative efficacy data were taken from a published network meta-analysis. Costs of treatment were calculated in 2020 Swiss francs (CHF) using a microcosting approach, and included the costs of iron, healthcare professional time, and consumables. Costs are also presented in euros (EUR) based on an exchange rate of CHF 1 = EUR 0.94.

RESULTS

Response rates with FCM, IIM, IS, and OI were 81%, 74%, 75%, and 69%, respectively, with FCM projected to be the most effective treatment. FCM was associated with cost savings of CHF 24 (EUR 23) versus IIM and of CHF 147 (EUR 138) versus IS, and increased costs by CHF 345 (EUR 324) versus OI. Therefore FCM was considered dominant versus both IIM and IS, improving clinical outcomes with cost savings. FCM was associated with an incremental cost-effectiveness ratio of CHF 2970 (EUR 2792) per additional responder versus OI.

CONCLUSIONS

FCM was projected to be the most cost-effective intravenous iron therapy in Switzerland, increasing the number of responders and leading to cost savings for healthcare payers.

Vitamin D Modulates Intestinal Microbiota in Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract (GIT), including Crohn's disease (CD) and ulcerative colitis (UC), which differ in the location and lesion extensions. Both diseases are associated with microbiota dysbiosis, with a reduced population of butyrate-producing species, abnormal inflammatory response, and micronutrient deficiency (e.g., vitamin D hypovitaminosis). Vitamin D (VitD) is involved in immune cell differentiation, gut microbiota modulation, gene transcription, and barrier integrity. Vitamin D receptor (VDR) regulates the biological actions of the active VitD (1α,25-dihydroxyvitamin D3), and is involved in the genetic, environmental, immune, and microbial aspects of IBD. VitD deficiency is correlated with disease activity and its administration targeting a concentration of 30 ng/mL may have the potential to reduce disease activity. Moreover, VDR regulates functions of T cells and Paneth cells and modulates release of antimicrobial peptides in gut microbiota-host interactions. Meanwhile, beneficial microbial metabolites, e.g., butyrate, upregulate the VDR signaling. In this review, we summarize the clinical progress and mechanism studies on VitD/VDR related to gut microbiota modulation in IBD. We also discuss epigenetics in IBD and the probiotic regulation of VDR. Furthermore, we discuss the existing challenges and future directions. There is a lack of well-designed clinical trials exploring the appropriate dose and the influence of gender, age, ethnicity, genetics, microbiome, and metabolic disorders in IBD subtypes. To move forward, we need well-designed therapeutic studies to examine whether enhanced vitamin D will restore functions of VDR and microbiome in inhibiting chronic inflammation.

IBS-Symptoms in IBD Patients-Manifestation of Concomitant or Different Entities

Irritable bowel syndrome (IBS) is a functional heterogenous disease with a multifactorial pathogenesis. It is characterized by abdominal pain, discomfort, and alteration in gut motility. The occurrence of similar symptoms was observed in patients in clinical remission of inflammatory bowel diseases (IBD) that is Crohn's disease (CD) and ulcerative colitis (UC), which pathogenesis is also not fully understood. Hence, arose the question if these symptoms are "true IBS" imposed on IBD, or is it a subclinical form of IBD or even pre-IBD? In this article, based on a narrative overview of the literature, we try to find an answer to this query by discussing the pathogenesis and overlaps between these conditions.

Immunocompetent Human Intestinal Models in Preclinical Drug Development

The intestinal epithelial barrier, together with the microbiome and local immune system, is a critical component that maintains intestinal homeostasis. Dysfunction may lead to chronic inflammation, as observed in inflammatory bowel diseases. Animal models have historically been used in preclinical research to identify and validate new drug targets in intestinal inflammatory diseases. Yet, limitations about their biological relevance to humans and advances in tissue engineering have forced the development of more complex three-dimensional reconstructed intestinal epithelium. By introducing immune and commensal microbial cells, these models more accurately mimic the gut's physiology and the pathophysiological changes occurring in vivo in the inflamed intestine. Specific advantages and limitations of two-dimensional (2D) and three-dimensional (3D) intestinal models such as coculture systems, organoids, and microfluidic devices to study inflammatory and immune-related responses are highlighted. While current cell culture models lack the cellular and molecular complexity observed in vivo, the emphasis is put on how these models can be used to improve preclinical drug development for inflammatory diseases of the intestine.

Ectoines as novel anti-inflammatory and tissue protective lead compounds with special focus on inflammatory bowel disease and lung inflammation

The compatible solute ectoine is one of the most abundant and powerful cytoprotectant in the microbial world. Due to its unique ability to stabilize biological membranes and macromolecules it has been successfully commercialized as ingredient of various over-the-counter drugs, achieving primarily epithelial protection. While trying to elucidate the mechanism of its cell protective properties in in-vitro studies, a significant anti-inflammatory effect was documented for the small molecule. The tissue protective potential of ectoine considerably improved organ quality during preservation. In addition, ectoine and derivatives have been demonstrated to significantly decrease inflammatory cytokine production, thereby alleviating the inflammatory response following organ transplantation, and launching new therapeutic options for pathologies such as Inflammatory Bowel Disease (IBD) and Chronic Obstructive Pulmonary Disease (COPD). In this review, we aim to summarize the knowledge of this fairly nascent field of the anti-inflammatory potential of diverse ectoines. We also point out that this promising field faces challenges in its biochemical and molecular substantiations, including defining the molecular mechanisms of the observed effects and their regulation. However, based on their potent cytoprotective, anti-inflammatory, and non-toxic properties we believe that ectoines represent promising candidates for risk free interventions in inflammatory pathologies with steeply increasing demands for new therapeutics.

Select animal models of colitis and their value in predicting clinical efficacy of biological therapies in ulcerative colitis

Introduction: Advancing new therapies from discovery to development usually requires proof-of-concept in animal models to justify the costs of continuing the program. While animal models are useful for understanding the mechanism of action (MOA) of a target, limitations of many published colitis models restrict their value to predict clinical efficacy.Areas covered: The authors focused their literature search on published studies of chronic animal models used to evaluate the pre-clinical efficacy of therapeutic molecules subsequently evaluated in clinical trials for UC. The UC therapies evaluated were anti-α4β7, anti-IL13, anti-IL12p40, and anti-IL23p19. The models of chronic colitis evaluating these molecules were: mdra1a-/-, chronic dextran sulfate sodium (DSS), chronic 2,4,6-trinitrobenzene sulfonic acid (TNBS), and the T cell transfer model.Expert opinion: While some models provide insight into target MOA in UC, none is consistently superior in predicting efficacy. Evaluation of multiple models, with varying mechanisms of colitis induction, is needed to understand potential drug efficacy. Additional models of greater complexity, reflecting the disease chronicity/heterogeneity seen in humans, are needed. Although helpful in prioritizing targets, animal models alone will likely not improve outcomes of UC clinical trials. Transformational changes to clinical efficacy will likely only occur when precision medicine approaches are employed.

Inflammatory Bowel Disease and Atherosclerotic Cardiovascular Disease: JACC Review Topic of the Week

Chronic inflammatory diseases including human immunodeficiency virus infection, psoriasis, rheumatoid arthritis, and systemic lupus erythematosus predispose to atherosclerotic cardiovascular disease (ASCVD). Inflammatory bowel disease (IBD) is a common chronic inflammatory condition, and the United States has the highest prevalence worldwide. IBD has so far been overlooked as a contributor to the burden of ASCVD among young and middle-age adults, but meta-analyses of cohort studies suggest that IBD is an independent risk factor for ASCVD. This review discusses the epidemiological links between IBD and ASCVD and potential mechanisms underlying these associations. ASCVD risk management of patients with IBD is challenging because of their young age and the inability of current risk scores to fully capture their increased risk. The role of IBD in current primary prevention guidelines is evaluated, and strategies for enhanced ASCVD risk reduction in patients with IBD are outlined. Finally, the authors discuss knowledge gaps and future research directions in this innovative field.

Arf1 and Arf6 Synergistically Maintain Survival of T Cells during Activation

ADP-ribosylation factor (Arf) family consisting of six family members, Arf1-Arf6, belongs to Ras superfamily and orchestrates vesicle trafficking under the control of guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins. It is well established that brefeldin A, a potent inhibitor of ArfGEFs, blocks cytokine secretion from activated T cells, suggesting that the Arf pathway plays important roles in T cell functions. In this study, because Arf1 and Arf6 are the best-characterized members among Arf family, we established T lineage-specific Arf1-deficient, Arf6-deficient, and Arf1/6 double-deficient mice to understand physiological roles of the Arf pathway in the immune system. Contrary to our expectation, Arf deficiency had little or no impact on cytokine secretion from the activated T cells. In contrast, the lack of both Arf1 and Arf6, but neither Arf1 nor Arf6 deficiency alone, rendered naive T cells susceptible to apoptosis upon TCR stimulation because of imbalanced expression of Bcl-2 family members. We further demonstrate that Arf1/6 deficiency in T cells alleviates autoimmune diseases like colitis and experimental autoimmune encephalomyelitis, whereas Ab response under Th2-polarizing conditions is seemingly normal. Our findings reveal an unexpected role for the Arf pathway in the survival of T cells during TCR-induced activation and its potential as a therapeutic target in the autoimmune diseases.

Challenges in the diagnosis and management of inflammatory bowel disease in resource-limited settings in Asia

Inflammatory bowel disease (IBD) is increasing in prevalence in resource-limited settings in Asia. Although the prevalence of IBD is lower in these settings than in high-income countries, the high disease burden due to large population size is projected to overtake that of high-income countries in the near future. Unique challenges exist for diagnosing and managing IBD in Asia. On one hand, the inadequate disease awareness in physicians and the general population, the scarcity of diagnostic services, the infectious mimics of IBD (specifically intestinal tuberculosis), and the widespread use of empirical antibiotics and antitubercular therapy pose diagnostic challenges. On the other hand, the absence of a centralised health-care delivery system or universal health insurance, the high cost of therapy, limited access to biologics, and the high risk of opportunistic infections with immunosuppressive therapy present therapeutic challenges. The high probability of tuberculosis reactivation often precludes biological therapy because Asia is highly endemic for tuberculosis and has a high prevalence of latent tuberculosis. Current screening strategies are often ineffective in ruling out latent tuberculosis. Hence, management strategies are often modified according to these challenges. This Series paper discusses the challenges in the diagnosis and management of IBD in resource-limited settings in Asia.

Whole Blood Profiling of T-cell-Derived microRNA Allows the Development of Prognostic models in Inflammatory Bowel Disease

BACKGROUND

MicroRNAs [miRNAs] are cell-specific small non-coding RNAs that can regulate gene expression and have been implicated in inflammatory bowel disease [IBD] pathogenesis. Here we define the cell-specific miRNA profiles and investigate its biomarker potential in IBD.

METHODS

In a two-stage prospective multi-centre case control study, next generation sequencing was performed on a discovery cohort of immunomagnetically separated leukocytes from 32 patients (nine Crohn's disease [CD], 14 ulcerative colitis [UC], eight healthy controls) and differentially expressed signals were validated in whole blood in 294 patients [97 UC, 98 CD, 98 non-IBD, 1 IBDU] using quantitative PCR. Correlations were analysed with phenotype, including need for early treatment escalation as a marker of progressive disease using Cox proportional hazards.

RESULTS

In stage 1, each leukocyte subset [CD4+ and CD8+ T-cells and CD14+ monocytes] was analysed in IBD and controls. Three specific miRNAs differentiated IBD from controls in CD4+ T-cells, including miR-1307-3p [p = 0.01], miR-3615 [p = 0.02] and miR-4792 [p = 0.01]. In the extension cohort, in stage 2, miR-1307-3p was able to predict disease progression in IBD (hazard ratio [HR] 1.98, interquartile range [IQR]: 1.20-3.27; logrank p = 1.80 × 10-3), in particular CD [HR 2.81; IQR: 1.11-3.53, p = 6.50 × 10-4]. Using blood-based multimarker miRNA models, the estimated chance of escalation in CD was 83% if two or more criteria were met and 90% for UC if three or more criteria are met.

INTERPRETATION

We have identified and validated unique CD4+ T-cell miRNAs that are differentially regulated in IBD. These miRNAs may be able to predict treatment escalation and have the potential for clinical translation; further prospective evaluation is now indicated.

Role and mechanisms of exosomal miRNAs in IBD pathophysiology

Exosomes represent secretory membranous vesicles used for the information exchange between cells and organ-to-organ communication. Exosome crosstalk mechanisms are involved in the regulation of several inflammatory bowel disease (IBD)-associated pathophysiological intestinal processes such as barrier function, immune responses, and intestinal flora. Functional biomolecules, mainly noncoding RNAs (ncRNAs), are believed to be transmitted between the mammalian cells via exosomes that likely play important roles in cell-to-cell communication, both locally and systemically. MicroRNAs (miRNAs) encapsulated in exosomes have generated substantial interest because of their critical roles in multiple pathophysiological processes. In addition, exosomal miRNAs are implicated in the gut health. MiRNAs are selectively and actively loaded into the exosomes and then transferred to the target recipient cell where they manipulate cell function through posttranscriptional silencing of target genes. Intriguingly, miRNA profile of exosomes differs from their cellular counterparts suggesting an active sorting and packaging mechanism of exosomal miRNAs. Even more exciting is the involvement of posttranscriptional modifications in the specific loading of miRNAs into exosomes, but the underlying mechanisms of how these modifications direct ncRNA sorting have not been established. This review gives a brief overview of the status of exosomes and exosomal miRNAs in IBD and also discusses potential mechanisms of exosomal miRNA sorting and delivering.

Sex matters: impact on pathogenesis, presentation and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD), as do most chronic inflammatory disorders, displays unique features and confers different risk factors in male and female patients. Importantly, sex-based differences in IBD exist for epidemiological incidence and prevalence among different age groups, with men and women developing distinct clinical symptoms and disparity in severity of disease. In addition, the presentation of comorbidities in IBD displays strong sex differences. Notably, particular issues exclusive to women's health, including pregnancy and childbirth, require specific considerations in female patients with IBD of childbearing age that can have a substantial influence on clinical outcomes. This Review summarizes the latest findings regarding sex-based differences in the epidemiology, clinical course, comorbidities and response to current therapies in patients with IBD. Importantly, the latest basic science discoveries in this area of investigation are evaluated to provide insight into potential mechanisms underlying the influence of sex on disease pathogenesis, as well as to design more personalized and efficacious care, in patients with IBD.

Disease- and Treatment-related Complications in Older Patients With Inflammatory Bowel Diseases: Comparison of Adult-onset vs Elderly-onset Disease

BACKGROUND

The incidence and prevalence of inflammatory bowel diseases (IBD) in older adults are rising. There is a limited comparative assessment of risk of disease- and treatment-related complications in older patients (older than 60 years) with adult-onset (age at disease onset, 18-59 years; AO-IBD) vs elderly-onset IBD (age at disease onset, older than 60 years; EO-IBD). We compared clinical outcomes in older patients with IBD with AO-IBD vs EO-IBD.

METHODS

We conducted a retrospective cohort study comparing risk of disease-related complications (IBD-related surgery, hospitalization, treatment escalation, clinical flare, or disease complication) and treatment-related complications (serious infection, malignancy, or death) in older patients with AO-IBD vs EO-IBD through Cox proportional hazard analysis, adjusting for age at cohort entry, disease phenotype, disease duration, prior surgery and/or hospitalization, medication use, disease activity at cohort entry, and comorbidities.

RESULTS

We included 356 older patients with IBD (AO-IBD, 191 patients, 67 ± 5 y at cohort entry; EO-IBD, 165 patients, 72 ± 8 y at cohort entry). No significant differences were observed in the risk of disease-related complications in older patients with prevalent vs incident IBD (adjusted hazard ratio [aHR], 0.85; 95% CI, 0.58-1.25), although risk of IBD-related surgery was lower in older patients with prevalent IBD (aHR, 0.47; 95% CI, 0.25-0.89). Older patients with prevalent IBD were significantly less likely to experience treatment-related complications (aHR, 0.58; 95% CI, 0.39-0.87).

CONCLUSION

Patients with AO-IBD have lower risk of treatment-related complications as they age compared with patients with EO-IBD, without a significant difference in risk of disease-related complications.

Emerging use of artificial intelligence in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a complex, immune-mediated gastrointestinal disorder with ill-defined etiology, multifaceted diagnostic criteria, and unpredictable treatment response. Innovations in IBD diagnostics, including developments in genomic sequencing and molecular analytics, have generated tremendous interest in leveraging these large data platforms into clinically meaningful tools. Artificial intelligence, through machine learning facilitates the interpretation of large arrays of data, and may provide insight to improving IBD outcomes. While potential applications of machine learning models are vast, further research is needed to generate standardized models that can be adapted to target IBD populations.