Influence of environmental factors on the onset and course of inflammatory bowel disease

Poria cocos Attenuated DSS-Induced Ulcerative Colitis via NF-κB Signaling Pathway and Regulating Gut Microbiota

Ulcerative colitis (UC), as a chronic inflammatory disease, presents a global public health threat. However, the mechanism of Poria cocos (PC) in treating UC remains unclear. Here, LC-MS/MS was carried out to identify the components of PC. The protective effect of PC against UC was evaluated by disease activity index (DAI), colon length and histological analysis in dextran sulfate sodium (DSS)-induced UC mice. ELISA, qPCR, and Western blot tests were conducted to assess the inflammatory state. Western blotting and immunohistochemistry techniques were employed to evaluate the expression of tight junction proteins. The sequencing of 16S rRNA was utilized for the analysis of gut microbiota regulation. The results showed that a total of fifty-two nutrients and active components were identified in PC. After treatment, PC significantly alleviated UC-associated symptoms including body weight loss, shortened colon, an increase in DAI score, histopathologic lesions. PC also reduced the levels of inflammatory cytokines TNF-α, IL-6, and IL-1β, as evidenced by the suppressed NF-κB pathway, restored the tight junction proteins ZO-1 and Claudin-1 in the colon, and promoted the diversity and abundance of beneficial gut microbiota. Collectively, these findings suggest that PC ameliorates colitis symptoms through the reduction in NF-κB signaling activation to mitigate inflammatory damage, thus repairing the intestinal barrier, and regulating the gut microbiota.

Using machine learning methods to analyze the association between urinary polycyclic aromatic hydrocarbons and chronic bowel disorders in American adults

The etiology of chronic bowel disorders is multifaceted, with environmental exposure to harmful substances potentially playing a significant role in their pathogenesis. However, research on the correlation between polycyclic aromatic hydrocarbons (PAHs) and chronic bowel disorders remains limited. Using data from the National Health and Nutrition Examination Survey (NHANES) conducted in 2009-2010, we investigated the relationship between 9 PAHs and chronic diarrhea and constipation in U.S. adults. We employed unsupervised methods such as clustering and Principal Component Analysis (PCA) to identify participants with similar exposure patterns. Additionally, we used supervised learning techniques, namely weighted quantile sum (WQS) and Bayesian kernel machine (BKMR) regressions, to assess the association between PAHs and the occurrence of chronic diarrhea and chronic constipation. PCA identified three principal components in the unsupervised analysis, explaining 86.5% of the total PAH variability. The first component displayed a mild association with chronic diarrhea, but no correlation with chronic constipation. Participants were divided into three clusters via K-means clustering, based on PAH concentrations. Clusters with higher PAH exposure demonstrated an increased odds ratio for chronic diarrhea, but no meaningful connection with chronic constipation. In the supervised analysis, the WQS regression underscored a positive relationship between the PAH mixture and chronic diarrhea, with three PAHs significantly impacting the mixture effect. The mixture index showed no correlation with chronic constipation. BKMR analysis illustrated a positive trend in the impact of four specific PAHs on chronic diarrhea, given other metabolites were fixed at their 50th percentiles. Our results suggest a clear association between higher PAH exposure and an increased risk of chronic diarrhea, but not chronic constipation. It also underscores the potential role of specific PAHs in contributing to the risk of chronic diarrhea.

Pre- and perinatal exposures associated with developing pediatric-onset immune-mediated inflammatory disease: A Danish nation-wide cohort study

OBJECTIVES

We aimed to identify pre- and perinatal risk factors for developing pediatric-onset immune-mediated inflammatory (pIMID).

METHODS

This nation-wide, cohort study included all children born in Denmark from 1994 to 2014 identified from the Danish Medical Birth registry. Individuals were followed through 2014 and cross-linked to the continuously updated national socioeconomic and healthcare registers to obtain data on pre- and perinatal exposures (maternal age, educational level, smoking, maternal IMID, parity, mode of conception and delivery, plurality, child's sex, and birth season). The primary outcome was a pIMID diagnosis (inflammatory bowel disease, autoimmune hepatitis, primary sclerosing cholangitis, juvenile idiopathic arthritis, or systemic lupus erythematosus) before 18 years of age. Risk estimates were calculated using Cox proportional hazards model and presented by hazard ratios (HR) with 95% confidence intervals (95%CI).

RESULTS

We included 1,350,353 children with a follow-up time of 14,158,433 person-years. Among these, 2,728 were diagnosed with a pIMID. We found a higher risk of pIMID in children born to women with a preconception IMID diagnosis (HR: 3.5 [95%CI: 2.7-4.6]), children born by Caesarean section (HR: 1.2 [95%CI: 1.0-1.3]), and among females (1.5 [95%CI: 1.4-1.6]) than among children without these characteristics. Plural pregnancies were associated with a lower risk of pIMID than single pregnancies (HR: 0.7 [95%CI: 0.6-0.9]).

CONCLUSIONS

Our results indicate a high genetic burden in pIMID but also identifies intervenable risk factors, such as Cesarean section. Physicians should, keep this in mind when caring for high-risk populations and pregnant women previously diagnosed with an IMID.

Platycodon grandiflorus polysaccharide regulates colonic immunity through mesenteric lymphatic circulation to attenuate ulcerative colitis

Platycodon grandiflorus polysaccharide (PGP) is one of the main components of P. grandiflorus, but the mechanism of its anti-inflammatory effect has not been fully elucidated. The aim of this study was to evaluate the therapeutic effect of PGP on mice with dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) and explore the underlying mechanisms. The results showed that PGP treatment inhibited the weight loss of DSS-induced UC mice, increased colon length, and reduced DAI, spleen index, and pathological damage within the colon. PGP also reduced the levels of pro-inflammatory cytokines and inhibited the enhancement of oxidative stress and MPO activity. Meanwhile, PGP restored the levels of Th1, Th2, Th17, and Treg cell-related cytokines and transcription factors in the colon to regulate colonic immunity. Further studies revealed that PGP regulated the balance of colonic immune cells through mesenteric lymphatic circulation. Taken together, PGP exerts anti-inflammatory and anti-oxidant effect and regulates colonic immunity to attenuate DSS-induced UC through mesenteric lymphatic circulation.

κ-Selenocarrageenan Oligosaccharides Prepared by Deep-Sea Enzyme Alleviate Inflammatory Responses and Modulate Gut Microbiota in Ulcerative Colitis Mice

κ-Selenocarrageenan (KSC) is an organic selenium (Se) polysaccharide. There has been no report of an enzyme that can degrade κ-selenocarrageenan to κ-selenocarrageenan oligosaccharides (KSCOs). This study explored an enzyme, κ-selenocarrageenase (SeCar), from deep-sea bacteria and produced heterologously in Escherichia coli, which degraded KSC to KSCOs. Chemical and spectroscopic analyses demonstrated that purified KSCOs in hydrolysates were composed mainly of selenium-galactobiose. Organic selenium foods through dietary supplementation could help regulate inflammatory bowel diseases (IBD). This study discussed the effects of KSCOs on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in C57BL/6 mice. The results showed that KSCOs alleviated the symptoms of UC and suppressed colonic inflammation by reducing the activity of myeloperoxidase (MPO) and regulating the unbalanced secretion of inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10). Furthermore, KSCOs treatment regulated the composition of gut microbiota, enriched the genera Bifidobacterium, Lachnospiraceae_NK4A136_group and Ruminococcus and inhibited Dubosiella, Turicibacter and Romboutsia. These findings proved that KSCOs obtained by enzymatic degradation could be utilized to prevent or treat UC.

Boris knockout eliminates AOM/DSS-induced in situ colorectal cancer by suppressing DNA damage repair and inflammation

The Brother of Regulator of Imprinted Sites (BORIS, gene symbol CTCFL) has previously been shown to promote colorectal cancer cell proliferation, inhibit cancer cell apoptosis, and resist chemotherapy. However, it is unknown whether Boris plays a role in the progression of in situ colorectal cancer. Here Boris knockout (KO) mice were constructed. The function loss of the cloned Boris mutation that was retained in KO mice was verified by testing its activities in colorectal cell lines compared with the Boris wild-type gene. Boris knockout reduced the incidence and severity of azoxymethane/dextran sulfate-sodium (AOM/DSS)-induced colon cancer. The importance of Boris is emphasized in the progression of in situ colorectal cancer. Boris knockout significantly promoted the phosphorylation of γH2AX and the DNA damage in colorectal cancer tissues and suppressed Wnt and MAPK pathways that are responsible for the callback of DNA damage repair. This indicates the strong inhibition of colorectal cancer in Boris KO mice. By considering that the DSS-promoted inflammation contributes to tumorigenesis, Boris KO mice were also studied in DSS-induced colitis. Our data showed that Boris knockout alleviated DSS-induced colitis and that Boris knockdown inhibited the NF-κB signaling pathway in RAW264.7 cells. Therefore Boris knockout eliminates colorectal cancer generation by inhibiting DNA damage repair in cancer cells and relieving inflammation in macrophages. Our findings demonstrate the importance of Boris in the development of in situ colorectal cancer and provide evidence for the feasibility of colorectal cancer therapy on Boris.

Evaluating the influence of environmental risk factors on inflammatory bowel diseases: a case-control study

Aim

This study aimed to examine the environmental factors associated in Iranian patients with inflammatory bowel disease (IBD).

Background

The role of environmental factors in the development of IBD remains uncertain.

Methods

In this case-control study, the patients with IBD referred to the Taleghani Hospital, Tehran, Iran, were recruited from 2017 to 2019. Controls were matched by sex. Data were collected using the designed questionnaire and also valid questionnaire such Pittsburgh Sleep Quality Index (PSQI) and Hospital Anxiety and Depression Scale (HADS) for sleep quality and anxiety/depression, respectively. Conditional logistic regression models were used to estimate adjusted odds ratios (ORs).

Results

The study population included 200 individuals: 100 (50%) IBD patients and 100 (50%) controls. Age under 50, marital status, sleep difficulties, vitamin D insufficiency, anxiety/depression, dietary fiber deficit, post-menopausal hormone treatment, oral contraceptives, and antibiotics were all prognostic factors for IBD on the univariate analysis (P< 0.005). In multivariate analysis, the risk of IBD was significantly increased with 50 years (OR: 6.699, 95%CI: 3.271-8.662, P=0.017), abnormal sleep status (OR: 6.383, 95%CI: 3.389-7.19, P=0.001), and using oral contraceptive (OR: 7.426, 95%CI: 5.327-9.865, P=0.001). However, the risk of IBD was significantly decreased with older age (OR: 0.795, 95%CI: 0.697-0.907, P=0.001) and married status (OR: 0.008, 95%CI: 0.001-0.438, P=0.018).

Conclusion

Data suggest that the environmental factors play a significant role in the etiology of IBD and probably on the disease course. While the evidence for some factors is strong, many factors require further supportive data.

Clinical and inflammatory biomarkers of inflammatory bowel diseases are linked to plasma trace elements and toxic metals; new insights into an old concept

Background

Inflammatory bowel diseases (IBD) are chronic immune-mediated diseases, mainly represented by Crohn's disease (CD) and ulcerative colitis (UC). Several environmental factors have been proposed to contribute to disease pathogenesis, amongst which are metals. These can affect the immune system and may be associated with IBD. The aim of the present cross-sectional study was to investigate blood levels of metals in IBD patients and to examine possible associations with clinical and inflammatory disease markers.

Methods

In total, 76 CD patients, 39 UC patients and 38 healthy controls were included. Blood and stool samples were collected. Metals were quantified in plasma samples using inductively coupled plasma mass spectrometry.

Results

There were more abnormalities of circulating metals in CD than in UC when compared to healthy controls. CD: Concentrations of the essential trace elements zinc and selenium were lower in CD patients than the controls. Chromium was negatively associated with serum IL-6 (Beta: -3.558, p = 0.011), and caesium with fecal calprotectin (Beta: -0.481, p = 0.038) and serum IL-10 (Beta: -1.912, p = 0.050). In contrast, copper was positively associated with C-reactive protein (Beta: 2.548 × 10², p = 0.033). UC: In UC, a negative association of iron with serum myeloperoxidase levels (Beta: -1.270 × 10³, p = 0.044) was detected. Thallium, a hazardous metal, however, was positively associated with disease activity (Beta: 3.899, p = < 0.01).

Conclusion

In conclusion, our study offers new insights into the relations of metals with IBD. Further research should focus on the evaluation of the above associations and potential underlying mechanisms.

Xuedan Sustained Release Pellets Ameliorate Dextran Sulfate Sodium-Induced Ulcerative Colitis in Rats by Targeting Gut Microbiota and MAPK Signaling Pathways

Cucurbitacins have a variety of bioactivities, such as anticancer, anti-inflammatory, antidepressant-like, and antiviral effects, but their pharmacological effect in ulcerative colitis (UC) has not been reported until now. Thus, this study aims to investigate the preventive effects of Xuedan sustained release pellets (XSPs) on UC rats and the underlying mechanisms. XSPs were prepared by extracting cucurbitacins from Hemsleya. Experimental UC rats were induced by the intake of 4% dextran sulfate sodium (DSS) for a week and treated with different doses of XSP (0.95, 1.90, and 3.8 mg/kg). The body weight, colon length, disease activity index (DAI), and histological changes of colonic tissue were measured. In addition, the expressions of pro-inflammatory cytokines were detected by using the enzyme-linked immunosorbent assay. Pathways involved in the intestinal inflammation were targeted by RNA-sequencing. Moreover, the changes of gut microbial diversity and composition were analyzed by the 16SrNA analysis and the contents of short-chain fatty acids (SCFAs) were detected by GC-MS. The results revealed that XSP intervention greatly restored the weight loss and colonic shortening (p < 0.05) and reduced the raised DAI scores, myeloperoxidase, and nitric oxide activities in UC in rats (p < 0.05). XSP administration also downregulated the protein levels of pro-inflammatory factors IL-1β, IL-6, and TNF-α. Notably, it was found that XSP considerably suppressed the activation of the MAPK signaling pathway. In addition, XSP treatment improved the balance of gut microbiota that was disturbed by DSS. The beneficial bacteria Lachnospiraceae_NK4A136 group and Lactobacillus at the genus level significantly increased in the XSP group, which had decreased with the use of DSS (p < 0.05). Pathogenic bacteria including Escherichia-Shigella and Bacteroides in UC in rats were reduced by XSP intervention. Furthermore, XSP significantly elevated the production of SCFAs in UC in rats (p < 0.05). These alterations in inflammatory status were accompanied with changes in gut microbiota diversity and SCFA production. In conclusion, XSP exhibited protective effects against DSS-induced UC in rats. XSP treatment decreased inflammation via modulation of gut microbiota composition and SCFA production.

Rediscovering the Therapeutic Potential of Agarwood in the Management of Chronic Inflammatory Diseases

The inflammatory response is a central aspect of the human immune system that acts as a defense mechanism to protect the body against infections and injuries. A dysregulated inflammatory response is a major health concern, as it can disrupt homeostasis and lead to a plethora of chronic inflammatory conditions. These chronic inflammatory diseases are one of the major causes of morbidity and mortality worldwide and the need for them to be managed in the long term has become a crucial task to alleviate symptoms and improve patients’ overall quality of life. Although various synthetic anti-inflammatory agents have been developed to date, these medications are associated with several adverse effects that have led to poor therapeutic outcomes. The hunt for novel alternatives to modulate underlying chronic inflammatory processes has unveiled nature to be a plentiful source. One such example is agarwood, which is a valuable resinous wood from the trees of Aquilaria spp. Agarwood has been widely utilized for medicinal purposes since ancient times due to its ability to relieve pain, asthmatic symptoms, and arrest vomiting. In terms of inflammation, the major constituent of agarwood, agarwood oil, has been shown to possess multiple bioactive compounds that can regulate molecular mechanisms of chronic inflammation, thereby producing a multitude of pharmacological functions for treating various inflammatory disorders. As such, agarwood oil presents great potential to be developed as a novel anti-inflammatory therapeutic to overcome the drawbacks of existing therapies and improve treatment outcomes. In this review, we have summarized the current literature on agarwood and its bioactive components and have highlighted the potential roles of agarwood oil in treating various chronic inflammatory diseases.

Structural characterization of polysaccharide from yellow sweet potato and ameliorates DSS-induced mice colitis by active GPR41/MEK/ERK 1/2 signaling pathway

A polysaccharide isolated from yellow sweet potato (Ipomoea batatas (L.) Lam.) consisted of Rha, Ara, Gal, Glc, GalA, GlcA with the ratio of 1.00, 2.00, 3.63, 1.21, 1.17, 1.14, respectively. The molecular weight (Mw) of RSPP-A was determinted to be 2.51×10⁶ kDa. Methylation, Nuclear Magnetic Resonance (NMR) (1D & 2D) and Fourier transform infrared spectroscopy (FT-IR) analysis indicated that RSPP-A possessed six glycosidic bonds including α-L-Araf-(1→, →5)-α-L-Araf-(1→, →6)-β-D-Galp-(1→, β-D-Glcp-(1→, →3)-α-L-Araf-(1→, →3)-α-L-Rhap-(1→. In dextran sulfate sodium (DSS) induced mouse-acute-colitis model, the results indicated that RSPP-A could down- regulate the secretion of IL-6 and IL-1β, and promote the secretion of IL-10 in serum and colon, which also suggested that RSPP-A could enhance the contents of short chain fatty acids(SCFAs) and up-regulate the expression of G protein-coupled receptor (GPR41) in colon. Moreover, the expression of Mitogen-activated protein kinase kinase (MEK), extracellular signal-regulated kinase 1/2 (ERK1/2) were up-regulated in colon after intervention with RSPP-A, result from above suggested that the anti-inflammatory activity might be related to the production of SCFA, activating GPR41/MEK/ERK1/2 signaling pathway.

Trends in targeted delivery of nanomaterials in colon cancer diagnosis and treatment

Colon cancer is an adenocarcinoma, which subsequently develops into malignant tumors, if not treated properly. The current colon cancer therapy mainly revolves around chemotherapy, radiotherapy and surgery, but the search continues for more effective interventions. With the advancement of nanoparticles (NPs), it is now possible to diagnose and treat colon cancers with different types, shapes, and sizes of NPs. Nanoformulations such as quantum dots, iron oxide, polymeric NPs, dendrimers, polypeptides, gold NPs, silver NPs, platinum NPs, and cerium oxide have been either extensively used alone or in combination with other nanomaterials or drugs in colon cancer diagnosis, and treatments. These nanoformulations possess high biocompatibility and bioavailability, which makes them the most suitable candidates for cancer treatment. The size and shape of NPs are critical to achieving an effective drug delivery in cancer treatment and diagnosis. Most NPs currently are under different testing phases (in vitro, preclinical, and clinical), whereas some of them have been approved for therapeutic applications. We have comprehensively reviewed the recent advances in the applications of NPs-based formulations in colon cancer diagnosis and treatment.

Oxidative Stress in the Pathogenesis of Crohn's Disease and the Interconnection with Immunological Response, Microbiota, External Environmental Factors, and Epigenetics

Inflammatory bowel disease (IBD) is a complex multifactorial disorder in which external and environmental factors have a large influence on its onset and development, especially in genetically susceptible individuals. Crohn’s disease (CD), one of the two types of IBD, is characterized by transmural inflammation, which is most frequently located in the region of the terminal ileum. Oxidative stress, caused by an overabundance of reactive oxygen species, is present locally and systemically in patients with CD and appears to be associated with the well-described imbalanced immune response and dysbiosis in the disease. Oxidative stress could also underlie some of the environmental risk factors proposed for CD. Although the exact etiopathology of CD remains unknown, the key role of oxidative stress in the pathogenesis of CD is extensively recognized. Epigenetics can provide a link between environmental factors and genetics, and numerous epigenetic changes associated with certain environmental risk factors, microbiota, and inflammation are reported in CD. Further attention needs to be focused on whether these epigenetic changes also have a primary role in the pathogenesis of CD, along with oxidative stress.

The Association between Drinking Water Quality and Inflammatory Bowel Disease-A Study in Eastern Croatia

The incidence rate of inflammatory bowel disease (IBD) is becoming a global health problem that could be caused by changes in environmental and lifestyle habits. The study aimed to identify the association between the quality of drinking water, i.e., physiochemical and biological aspects of the phenotype and activity of IBD in Eastern Croatia. The study included 312 patients (63.4% ulcerative colitis, UC, and 36.6% Crohn's disease, CD) from the area of Eastern Croatia. The data were collected by questionnaires and the analysis of the water safety, based on 65 samples of drinking water by the patient's water supply method (public supply, rural water supply, and private well). IBD was active in 38.0% patients (34.0% CD and 40.0% UC). Significant differences (p = 0.001) were observed in the distribution of patients, according to counties in which they lived in. The largest deviation was noted in coliform bacteria, Escherichia coli, and enterococci bacteria, Fe, Al, and nitrate in rural water supply and private wells, although, without significant impact on IBD phenotype and activity. The hazard quotient (HQ) simulations showed that children are a sensitive group, regarding exposure to nitrates in drinking water over a long period of time, so there is a need for further monitoring and analysis of this issue.

Identifying environmental risk factors for inflammatory bowel diseases: a Mendelian randomization study

Several studies have examined environmental factors and inflammatory bowel diseases (IBD) using traditional approaches; however, provided results are still conflicting. Our aim was to determine whether lifestyle and nutrient exposures, related to IBD in observational meta-analyses, influence IBD risk using a Mendelian randomization (MR) approach. A two-sample MR approach was applied on summary-level genome-wide association results. Genetic variants strongly associated with measures of tobacco smoking, obesity and fat distribution, physical activity, and blood levels of vitamins and fatty acids were evaluated on genetic data from international IBD consortia including a total of 25,042 IBD cases (12,194 cases of Crohn’s disease (CD) and 12,366 cases of ulcerative colitis (UC)) and 34,915 controls. Our results indicated that, among lifestyle exposures, being a smoker was positively associated with CD (OR 1.13, P = 0.02), but it was not associated with UC risk (OR 0.99, P = 0.88). Body-mass index (BMI) and body fat percentage were positively associated with CD (OR 1.11, P = 0.02, per standard deviation (SD) of 4.6 kg/m²; and OR 1.50, P = 3 × 10^–10, per SD of 6.6%; respectively); while for UC, BMI was inversely associated (OR 0.85, P = 5 × 10^–5; per SD) and body fat percentage showed a OR of 1.11 (P = 0.11; per SD). Additionally, among nutrient exposures, omega-3 fatty acids levels were inversely associated with CD (OR 0.67, P = 2 × 10^–6). Our MR results did not support a protective effect for being a smoker on UC risk; however, they are compatible with a risk effect for higher body fat proportion and a protective role for higher levels of omega-3 fatty acids on CD etiology.

Development of a susceptibility gene based novel predictive model for the diagnosis of ulcerative colitis using random forest and artificial neural network

Ulcerative colitis is a type of inflammatory bowel disease characterized by chronic and recurrent nonspecific inflammation of the intestinal tract. To find susceptibility genes and develop a novel predictive model of ulcerative colitis, two sets of cases and a control group containing the ulcerative colitis gene expression profile (training set GSE109142 and validation set GSE92415) were downloaded and used to identify differentially expressed genes. A total of 781 upregulated and 127 downregulated differentially expressed genes were identified in GSE109142. The random forest algorithm was introduced to determine 1 downregulated and 29 upregulated differentially expressed genes contributing highest to ulcerative colitis occurrence. Expression data of these 30 genes were transformed into gene expression scores, and an artificial neural network model was developed to calculate differentially expressed genes weights to ulcerative colitis. We established a universal molecular prognostic score (mPS) based on the expression data of the 30 genes and verified the mPS system with GSE92415. Prediction results agreed with that of an independent data set (ROC-AUC=0.9506/PR-AUC=0.9747). Our research creates a reliable predictive model for the diagnosis of ulcerative colitis, and provides an alternative marker panel for further research in disease early screening

M10, a Myricetin-3-O-b-D-Lactose Sodium Salt, Prevents Ulcerative Colitis Through Inhibiting Necroptosis in Mice

Background

M10 is a derivative of Myricetin by adding a hydrophilic glycosylation group. Our previous study revealed that M10 by oral administration prevented colitis-associated colonic cancer (CAC) through attenuating endoplasmic reticulum stress in mice. In current study, we evaluated the inhibitory effects of M10 on ulcerative colitis in mice model, the mechanism of M10 in preventing colitis was further investigated.

Methods

Mice model of ulcerative colitis was induced by continuous oral dextran sodium sulfate (DSS). M10 was given gavage once a day for 12 consecutive weeks. Disease activity index (DAI) was recorded by analyzing the symptoms of colitis. Intestinal barrier was analyzed by the Immunofluorescence staining assay. The structure of microvilli of intestinal epithelial cells was analyzed under Transmission electron microscopy (TEM). TEM assay was also performed to determine the formation of necroptosis in the colonic epithelium with ulcerative colitis. We performed Western blotting assay to analyze the IL-6 and NF-κB pathways, as well as the cytokine cascades related to TNF-α signaling pathway during necroptosis.

Results

M10 by oral administration demonstrated a prevention of ulcerative colitis, showing a significant decrease of DAI as compared to the model mice. Pathological analysis indicated that M10 attenuated the degree of colonic inflammation in colonic tissues. M10 restored the structures of intestinal barrier damaged by DSS. M10 prevented the activation of the IL-6 and NF-κB signaling pathways in the inflamed colonic epithelium. Further, M10 prevented necroptosis in the inflamed colonic mucosal cells through down-regulating the TNF-α pathway. Importantly, M10 demonstrated higher activities in preventing ulcerative colitis than Myricetin and control drug Mesalazine.

Conclusions

Myricetin derivative M10 prevents chronic ulcerative colitis through inhibiting necroptosis. M10 could be developed as a promising drug for the treatment of chronic ulcerative colitis.

Crohn's disease and environmental contamination: Current challenges and perspectives in exposure evaluation

Although the incidence of Crohn's disease has increased worldwide over the past 30 years, the disorder's exact causes and physiological mechanisms have yet to be determined. Given that genetic determinants alone do not explain the development of Crohn's disease, there is growing interest in "environmental" determinants. In medical science, the term "environment" refers to both the ecological and social surroundings; however, most published studies have focused on the latter. In environmental and exposure sciences, the term "environment" mostly relates to contamination of the biotope. There are many unanswered questions on how environmental hazards might contribute to the pathogenesis of Crohn's disease. Which pollutants should be considered? Which mechanisms are involved? And how should environmental contamination and exposure be evaluated? The objective was to perform a systematic review of the literature on Crohn's disease and environmental contamination. We searched the PubMed, Google Scholar, Scopus, ISI Web of Science and Prospero databases. We considered all field studies previous to April 2019 conducted on human health indicators, and evaluating exposure to all type of physical, biological and chemical contamination of the environment. The lack of clear answers to date can be ascribed to the small total number of field studies (n = 16 of 39 publications, most of which were conducted by pioneering medical scientists), methodological differences, and the small number of contaminants evaluated. This make it impossible to conduct a coherent and efficient meta-analysis. Based on individual analysis of available studies, we formulated five recommendations on improving future research: (i) follow up the currently identified leads - especially metals and endocrine disruptors; (ii) explore soil contamination; (iii) gain a better knowledge of exposure mechanisms by developing transdisciplinary studies; (iv) identify the most plausible contaminants by developing approaches based on the source-to-target distance; and (v) develop registries and cohort-based analyses.

Risk factors associated with inflammatory bowel disease: A multicenter case-control study in Brazil

BACKGROUND

The etiology of inflammatory bowel disease (IBD) is unknown, but it is believed to be multifactorial. The hygiene hypothesis proposes that better hygiene conditions would lead to less infectious disease during childhood and favor the development of immune-mediated diseases.

AIM

To test the hygiene hypothesis in IBD by assessing the environmental risk factors associated with IBD development in different regions of Brazil with diverse socioeconomic development indices.

METHODS

A multicenter case-control study was carried out with 548 Crohn’s disease (CD) and 492 ulcerative colitis (UC) outpatients and 416 healthy controls, from six IBD centers within different Brazilian states at diverse socioeconomic development stages. A semi-structured questionnaire with 87 socioeconomic and environmental questions was applied. Logistic regression model was created to assess the odds ratio (OR) with P value and 95% confidence intervals (CI).

RESULTS

Predictive variables for both diseases (CD and UC) were women [odd ratios (OR) = 1.31; OR = 1.69], low monthly family income (OR = 1.78; OR = 1.57), lower number of cohabitants (OR = 1.70; OR = 1.60), absence of vaccination (OR = 3.11; OR = 2.51), previous history of bowel infections (OR = 1.78; OR = 1.49), and family history of IBD (OR = 5.26; OR = 3.33). Associated risk factors for CD were age (18-39 years) (OR = 1.73), higher educational level (OR = 2.22), absence of infectious childhood diseases (OR = 1.99). The UC predictive variables were living in an urban area (OR = 1.62), inadequate living conditions (OR = 1.48) and former smokers (OR = 3.36). Appendectomy was a risk factor for CD (OR = 1.58) with inverse association with UC (OR = 4.79). Consumption of treated and untreated water was associated with risk of CD (OR = 1.38) and UC (OR = 1.53), respectively.

CONCLUSION

This is the first examining environmental exposures as risk factors for inflammatory bowel disease in Brazil. Most of the variables associated with disease risk support the role of the hygiene hypothesis in IBD development.

Systematic review and meta-analysis: Association of a pre-illness Western dietary pattern with the risk of developing inflammatory bowel disease

OBJECTIVE

Previous studies have presented conflicting results on Western diets and the risk of inflammatory bowel disease (IBD). This study aimed to evaluate the role of a pre-illness Western dietary pattern in the development of IBD.

METHODS

The Western dietary pattern was defined as that met at least two of the following, either a high intake of refined grains, red and processed meat, animal protein, animal fats or high-fat dairy products, or with a low consumption of fruit and vegetables. Four medical databases (PubMed, EMBASE, the Cochrane Library and the China National Knowledge Infrastructure) were searched to identify all relevant references. Risk estimate and corresponding 95% confidence interval (CI) were pooled using a random-effects model.

RESULTS

Nine studies (seven case-control studies and two prospective cohorts) were included, with a total of 1491 IBD cases and 53 089 controls. A Western dietary pattern was associated with a risk of all IBD (relative risk [RR] 1.92, 95% CI 1.37-2.68) and separately with Crohn's disease (CD) (RR 1.72, 95% CI 1.01-2.93) and ulcerative colitis (UC) (RR 2.15, 95% CI 1.38-3.34). Subgroup analysis by region showed that a Western dietary pattern was associated with the risk of CD and UC for studies performed in Europe (RR 2.25, 95% CI 1.44-3.50 for CD; RR 2.65, 95% CI 1.61-4.36 for UC). The pooled RR was 2.26 (95% CI 1.42-3.59) in the pediatric CD subgroup.

CONCLUSION

This meta-analysis indicates that a pre-illness Western dietary pattern may increase the risk of developing CD and UC.

Risk of impaired nutritional status and flare occurrence in IBD outpatients

BACKGROUND

Inflammatory bowel disease (IBD) patients are at risk of an impaired nutritional status. The impact thereof on the IBD relapse risk is clinically relevant, though sparsely investigated.

AIM

The aim was to explore the association between an impaired nutritional status risk and the occurrence of disease flares in IBD outpatients participating in a longitudinal telemedicine study.

METHODS

IBD outpatients were recruited from the myIBDcoach study cohort, with one year clinical follow-up. Through myIBDcoach, a telemedicine tool, patients reported on disease activity and risk of impaired nutritional status (i.e. Short Nutritional Assessment Questionnaire >1 and/or BMI < 18.5 kg/m²) every one to three months. Data was analysed by generalized estimating equation modelling.

RESULTS

In total, 417 patients were included. During follow-up, 49 patients (11.8%) flared after initial clinical remission and 53 patients (12.7%) showed an increased risk of impaired nutritional status. The risk of impaired nutritional status was associated with flare occurrence (OR 2.61 (95% CI 1.02-6.69)).

CONCLUSIONS

The risk of an impaired nutritional status was associated with subsequent flares in IBD outpatients. This emphasizes the importance of monitoring disease activity in IBD patients at risk of impaired nutritional status.

Is fasting beneficial for hospitalized patients with inflammatory bowel diseases?

Background/Aims

Patients with inflammatory bowel disease (IBD) are usually hospitalized because of aggravated gastrointestinal symptoms. Many clinicians empirically advise these patients to fast once they are admitted. However, there has been no evidence that maintaining a complete bowel rest improves the disease course. Therefore, we aimed to investigate the effects of fasting on disease course in admitted patients with IBD or intestinal Behçet’s disease.

Methods

A total of 222 patients with IBD or intestinal Behçet’s disease, who were admitted for disease-related symptoms, were retrospectively analyzed. We divided them into 2 groups: fasting group (allowed to take sips of water but no food at the time of admission) and dietary group (received liquid, soft, or general diet).

Results

On admission, 124 patients (55.9%) started fasting and 98 patients (44.1%) started diet immediately. Among patients hospitalized through the emergency room, a significantly higher proportion underwent fasting (63.7% vs. 21.4%, P<0.001); however, 96.0% of the patients experienced dietary changes. Corticosteroid use (P<0.001; hazard ratio, 2.445; 95% confidence interval, 1.506–3.969) was significantly associated with a reduction in the disease activity score, although there was no significant difference between the fasting group and the dietary group in disease activity reduction (P=0.111) on multivariate analysis.

Conclusions

In terms of disease activity reduction, there was no significant difference between the fasting and dietary groups in admitted patients with IBD, suggesting that imprudent fasting is not helpful in improving the disease course. Therefore, peroral diet should not be avoided unless not tolerated by the patient.

THE EFFECT OF DAILY PHYSICAL ACTIVITY ON THE ACTIVITY OF INFLAMMATORY BOWEL DISEASES IN THERAPY-FREE PATIENTS

It has been suggested that various environmental factors play a very important role in the etiology of inflammatory bowel diseases (IBDs) and that they have a significant effect on the course of these diseases. The aim of this study was to investigate the effect of daily physical activity on the activity of IBDs in therapy-free patients. This cross-sectional population based study was conducted in eastern Croatia from January to June 2016. The study included 312 patients, mean age 49.9±15.0 years, 53.2% of males and 46.8% of females; there were 63.4% of ulcerative colitis (UC) and 36.6% of Crohn’s disease (CD) patients. Sociodemographic characteristics of patients, data on their daily physical activity and type of therapy taken were collected through a specifically designed and validated questionnaire, while the activity of UC and CD was evaluated using the Mayo index and Harvey-Bradshaw index. The study showed that 24.0% of patients were not taking therapy. Daily physical activity was connected to IBD in study patients when taking both diseases collectively (Fisher exact test; p<0.001), as well as to the inactivity of CD (Fisher exact test; p=0.001) and UC (Fisher exact test; p=0.006), when observing each disease separately. Daily physical activity was connected to the inactivity of IBDs in patients not taking therapy. It is necessary to educate all IBD patients about the importance of physical activity in order to control their disease.

Bases for the Adequate Development of Nutritional Recommendations for Patients with Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic and relapsing inflammatory condition of the gastrointestinal tract; it is a heterogeneous and multifactorial disorder resulting from a complex interplay between genetic variation, intestinal microbiota, the host immune system and environmental factors such as diet, drugs, breastfeeding and smoking. The interactions between dietary nutrients and intestinal immunity are complex. There is a compelling argument for environmental factors such as diet playing a role in the cause and course of IBD, given that three important factors in the pathogenesis of IBD can be modulated and controlled by diet: intestinal microbiota, the immune system and epithelial barrier function. The aim of this review is to summarize the epidemiological findings regarding diet and to focus on the effects that nutrients exert on the intestinal mucosa–microbiota–permeability interaction. The nature of these interactions in IBD is influenced by alterations in the nutritional metabolism of the gut microbiota and host cells that can influence the outcome of nutritional intervention. A better understanding of diet–host–microbiota interactions is essential for unravelling the complex molecular basis of epigenetic, genetic and environmental interactions underlying IBD pathogenesis as well as for offering new therapeutic approaches for the treatment of IBD.

A holistic view of gallic acid-induced attenuation in colitis based on microbiome-metabolomics analysis

GA enema can treat UC by influencing microbiota-mediated metabolism.

Cross-Sectional Analysis of Overall Dietary Intake and Mediterranean Dietary Pattern in Patients with Crohn's Disease

The primary objective of this study was to explore the macro- and micro-nutrient intakes and dietary patterns of patients with Crohn's disease (CD). Secondary objectives were to (a) compare the micronutrient intakes of CD patients with a representative sample of individuals, (b) describe the macro- and micronutrient intakes of male and female CD patients, and (c) describe Mediterranean diet scores (P-MDS) of male and female CD patients in remission that were recruited from an inflammatory bowel disease (IBD) clinic in Calgary, AB. Consecutive patients with ileal and/or colonic CD in endoscopic remission were recruited for participation in this cross-sectional study. Sixty-seven patients were enrolled with a mean age of 45, and a Body Mass Index (BMI) ≥ 25. Compared with the representative sample, patients with CD had similar energy, protein, carbohydrate, and total fat intake. However, polyunsaturated fats (PUFA), omega-6 and 3, and monounsaturated fats (MUFA) were lower in CD patients and dietary fiber intake was higher (p < 0.05). Vitamins C, D, thiamin, niacin, magnesium, phosphorus, zinc, and potassium were all significantly lower in all CD patients when compared to the representative sample (p < 0.05). Few patients with CD met the P-MDS criteria and overall scores were low (mean 4.5, Standard Deviation (SD) = 1.1 in males and 4.7, SD = 1.8 in females). The CD patients in this study had suboptimal dietary intakes and patterns and these data may be used to inform future dietary interventions in this population to improve intake.

Changes in duodenal CD163-positive cells in dogs with chronic enteropathy after successful treatment

Chronic enteropathy (CE) in dogs is characterized retrospectively per treatment response as food-responsive enteropathy (FRE), antibiotic-responsive enteropathy (ARE), and immunosuppressant-responsive enteropathy (IRE) - the latter most resembling inflammatory bowel disease in people. The aim of this study was to characterize duodenal macrophages (Mϕ) in CE using immunohistochemistry; with calprotectin (CAL) as a marker of early differentiated Mϕ and CD163 expression as a marker for resident Mϕ in the duodenum before and after treatment. Prior to treatment, dogs with FRE and IRE had a lower CD163⁺/CAL⁺ ratio than control dogs (CTRL) in crypts; this increased significantly and normalized compared with CTRL after treatment. Conversely, the CD163⁺/CAL⁺ ratio in dogs with ARE was comparable to that in healthy dogs before and after treatment. In summary, these results suggest that Mϕ play a role in the pathogenesis of CE in FRE and IRE, with a decrease in resident Mϕ and an increase in early differentiated Mϕ, but not in ARE dogs. Mϕ normalize after successful treatment.

Sodium chloride exacerbates dextran sulfate sodium-induced colitis by tuning proinflammatory and antiinflammatory lamina propria mononuclear cells through p38/MAPK pathway in mice

AIM

To investigate the influence of high salt on dextran sulfate sodium (DSS)-induced colitis in mice and explore the underlying mechanisms of this effect.

METHODS

DSS and NaCl were used to establish the proinflammatory animal model. We evaluated the colitis severity. Flow cytometry was employed for detecting the frequencies of Th1, macrophages and Tregs in spleen, mesenteric lymph node and lamina propria. The important role of macrophages in the promotion of DSS-induced colitis by NaCl was evaluated by depleting macrophages with clodronate liposomes. Activated peritoneal macrophages and lamina propria mononuclear cells (LPMCs) were stimulated with NaCl, and proteins were detected by western blotting. Cytokines and inflammation genes were analyzed by enzyme-linked immunosorbent assay and RT-PCR, respectively.

RESULTS

The study findings indicate that NaCl up-regulates the frequencies of CD11b+ macrophages and CD4+IFN-γ+IL-17+ T cells in lamina propria in DSS-treated mice. CD3+CD4+CD25+Foxp3+ T cells, which can secrete high levels of IL-10 and TGF-β, increase through feedback in NaCl- and DSS-treated mice. Furthermore, clodronate liposomes pretreatment significantly alleviated DSS-induced colitis, indicating that macrophages play a vital role in NaCl proinflammatory activity. NaCl aggravates peritoneal macrophage inflammation by promoting the expressions of interleukin (IL)-1, IL-6 and mouse inducible nitric oxide synthase. Specifically, high NaCl concentrations promote p38 phosphorylation in lipopolysaccharide- and IFN-γ-activated LPMCs mediated by SGK1.

CONCLUSION

Proinflammatory macrophages may play an essential role in the onset and development of NaCl-promoted inflammation in DSS-induced colitis. The underlining mechanism involves up-regulation of the p38/MAPK axis.

Impaired objective and subjective sleep in children and adolescents with inflammatory bowel disease compared to healthy controls

OBJECTIVE

Poor sleep and higher inflammation markers are associated, and impaired sleep quality is common among patients with inflammatory bowel disease (IBD). However, information on sleep among children and adolescents with IBD is currently lacking. The aims of the present study were to compare subjective and objective sleep of children and adolescents with IBD with healthy controls and to shed more light on the relationship between sleep and inflammation. We expected that poor sleep, as assessed via sleep electroencephalography recordings, would be observed among participants with IBD, but particularly among participants in an active state of disease. Furthermore, we expected that poor sleep and higher inflammatory markers would be associated.

METHODS

A total of 47 children and adolescents participated in the study; 23 were diagnosed with IBD (mean age: 13.88 years, 44% female). The IBD group was divided into a medically well adjusted "remission-group" (IBD-RE; n = 14) and a group with an "active state of disease" (IBD-AD; n = 8). Healthy controls (HC; n = 24) were age and gender matched. Participants completed self-rating questionnaires for subjective sleep disturbances. Anthropometric data, acute and chronic inflammatory markers (C-reactive protein [CRP] and erythrocyte sedimentation rate [ESR]) and objective sleep were considered.

RESULTS

Compared to HC and IBD-RE, IBD-AD patients showed impaired objective sleep patterns (eg, more awakenings, longer sleep latency, and reduced stage 3 sleep). Linear relationships described the correlation between higher ESR and more stage 4 (minutes, percentage) sleep. Nonlinear relationships described the relation between ESR and subjective sleep quality (inverse U-shaped) and between CRP and sleep latency (U-shaped).

CONCLUSION

In children and adolescents with an active IBD, objective sleep was impaired and overall sleep quality and inflammation indices were associated in a complex manner. It seems advisable to include assessment of subjective sleep quality in the care of pediatric IBD patients as an additional indicator for objective sleep disturbances and inflammation.

TRIAL REGISTRATION NUMBER

NCT02264275.

Influence of Diet on the Course of Inflammatory Bowel Disease

BACKGROUND

While the importance of diet in the pathogenesis of inflammatory bowel disease (IBD) is generally recognized, influence of food on the course of IBD is little understood.

AIM

The purpose of this study was to assess the association between food intake and course of disease in patients with IBD.

METHODS

We performed a cross-sectional study on 103 adult patients (50 with active disease and 53 in remission, divided by their calprotectin level), who completed a food frequency questionnaire on their intake of several foods over 1 year. Diet, as assessed using a 146-item self-administered food frequency questionnaire, was correlated with objective evidence of disease based on fecal calprotectin levels.

RESULTS

Legumes and potato were inversely associated with disease relapse (p value for trend 0.023) with patients in the highest quartile for legume and potato consumption carrying a 79% lower risk of active disease (adjusted OR 0.21, 95% CI 0.57-0.81). A positive association emerged between meat intake and disease relapse, the highest quartile for meat consumption coinciding with a higher risk of active disease (OR 3.61, 95% CI 1.15-11.38), though this was not significant in the adjusted analysis. No statistically significant associations were found between disease relapse and the intake of vegetables, cereals, dairy products, or fish.

CONCLUSIONS

Our results suggest a potentially protective role of legumes and potato and a detrimental influence of meat in maintaining clinical remission in IBD patients. These findings have important public health implications, but further interventional studies will be needed to demonstrate these associations.