Zinc intake and risk of Crohn’s disease and ulcerative colitis: a prospective cohort study

The association of ultra-processed food consumption with adult inflammatory bowel disease risk: a systematic review and dose-response meta-analysis of 4 035 694 participants

CONTEXT

There is an inconsistency between the results obtained from observational studies regarding intake of ultra-processed foods (UPFs) and the risk of inflammatory bowel disease (IBD).

OBJECTIVES

A dose-response meta-analysis was performed to evaluate the relationship between UPF intake and the risk of IBD.

DATA SOURCES

Searches were performed in the PubMed, ISI Web of Science, and Scopus databases up to November 2, 2022.

DATA EXTRACTION

Data were available from 24 studies including a total of 4 035 694 participants from 20 countries.

DATA ANALYSIS

Risk ratios for IBD were analyzed by a random-effects model. Outcomes indicated that UPF intake was linked to an increased risk of IBD (relative risk [RR], 1.13; 95%CI, 1.06-1.21; P = 0.001; I2 = 73.2%; n = 59; N = 4 035 694). This association was significant, especially for the risk of Crohn's disease (CD) (RR, 1.19; 95%CI, 1.00-1.41; I2 = 78.2%; P = 0.046; n = 23; N = 2 167 160), unlike the risk of ulcerative colitis (UC) (RR = 1.11; 95%CI, 0.99-1.26; P = 0.085; I2 = 60.3%; n = 27; N = 2 167 918). Also, results revealed that each 10% enhancement in daily UPF intake was not related to the risk of IBD (RR, 1.05; 95%CI, 0.98-1.14; P = 0.168; I2 = 31.9%; n = 4) or the risk of UC (RR, 1.01; 95%CI, 0.92-1.11; P = 0.876; I2 = 34.7%; n = 2) in adults. However, results suggested that for every 10% increase in daily UPF intake, there was a 19% increase in the risk of CD (RR, 1.19; 95%CI, 1.01-1.32; P = 0.021; I2 = 0.0%; n = 2) among adults. In addition, the results showed a positive linear relation between UPF intake with CD risk (Pnonlinearity = 0.431; Pdose response = 0.049) but not risk of IBD or UC.

CONCLUSION

High intake of UPFs was linked with an enhanced IBD risk, a specific risk of CD. However, conducting more observational studies among several ethnicities and using specific tools that accurately assess the amount of UPF consumption, components of UPFs, and food additives may be necessary. Systematic Review Registration: PROSPERO registration no. CRD42023390258.

Zinc and Inflammatory Bowel Disease: From Clinical Study to Animal Experiment

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract (GI) with a high incidence rate globally, and IBD patients are often accompanied by zinc deficiency. This review aims to summarize the potential therapeutic value of zinc supplementation in IBD clinical patients and animal models. Zinc supplementation can relieve the severity of IBD especially in patients with zinc deficiency. The clinical severity of IBD were mainly evaluated through some scoring methods involving clinical performance, endoscopic observation, blood biochemistry, and pathologic biopsy. Through conducting animal experiments, it has been found that zinc plays an important role in alleviating clinical symptoms and improving pathological lesions. In both clinical observation and animal experiment of IBD, the therapeutic mechanisms of zinc interventions have been found to be related to immunomodulation, intestinal epithelial repair, and gut microbiota's balance. Furthermore, the antioxidant activity of zinc was clarified in animal experiment. Appropriate zinc supplementation is beneficial for IBD therapy, and the present evidence highlights that alleviating zinc-deficient status can effectively improve the severity of clinical symptoms in IBD patients and animal models.

Environmental and Microbial Factors in Inflammatory Bowel Disease Model Establishment: A Review Partly through Mendelian Randomization

Inflammatory bowel disease (IBD) is a complex condition resulting from environmental, microbial, immunologic, and genetic factors. With the advancement of Mendelian randomization research in IBD, we have gained new insights into the relationship between these factors and IBD. Many animal models of IBD have been developed using different methods, but few studies have attempted to model IBD by combining environmental factors and microbial factors. In this review, we examine how environmental factors and microbial factors affect the development and progression of IBD, and how they interact with each other and with the intestinal microbiota. We also summarize the current methods for creating animal models of IBD and compare their advantages and disadvantages. Based on the latest findings from Mendelian randomization studies on the role of environmental factors in IBD, we discuss which environmental and microbial factors could be used to construct a more realistic and reliable IBD experimental model. We propose that animal models of IBD should consider both environmental and microbial factors to better mimic human IBD pathogenesis and to reveal the underlying mechanisms of IBD at the immune and genetic levels. We highlight the importance of environmental and microbial factors in IBD pathogenesis and offer new perspectives and suggestions for improving experimental animal modeling. Our goal is to create a model that closely resembles the clinical picture of IBD.

Role of diet in prevention versus treatment of Crohn's disease and ulcerative colitis

Diet is a modifiable risk factor for disease course and data over the past decade have emerged to indicate its role in Crohn's disease (CD) and ulcerative colitis (UC). However, literature is riddled with misinterpretation of data, often leading to unexpected or conflicting results. The key understanding is that causative factors in disease development do not always proceed to an opportunity to change disease course, once established. Here, we discuss the data on dietary influences in three distinct disease states for CD and UC-predisease, active disease and quiescent disease. We appraise the literature for how our dietary recommendations should be shaped to prevent disease development and if or how that differs for CD and UC induction therapy and maintenance therapy. In UC, principles of healthy eating are likely to play a role in all states of disease. Conversely, data linking dietary factors to CD prevention and treatment are paradoxical with the highest quality evidence for CD treatment being exclusive enteral nutrition, a lactose, gluten and fibre-free diet comprising solely of ultraprocessed food-all dietary factors that are not associated or inversely associated with CD prevention. High-quality evidence from dietary trials is much awaited to expand our understanding and ultimately lead our dietary recommendations for targeted patient populations.

Intestinal Barrier Impairment Induced by Gut Microbiome and Its Metabolites in School-Age Children with Zinc Deficiency

Zinc deficiency affects the physical and intellectual development of school-age children, while studies on the effects on intestinal microbes and metabolites in school-age children have not been reported. School-age children were enrolled to conduct anthropometric measurements and serum zinc and serum inflammatory factors detection, and children were divided into a zinc deficiency group (ZD) and control group (CK) based on the results of serum zinc. Stool samples were collected to conduct metagenome, metabolome, and diversity analysis, and species composition analysis, functional annotation, and correlation analysis were conducted to further explore the function and composition of the gut flora and metabolites of children with zinc deficiency. Beta-diversity analysis revealed a significantly different gut microbial community composition between ZD and CK groups. For instance, the relative abundances of Phocaeicola vulgatus, Alistipes putredinis, Bacteroides uniformis, Phocaeicola sp000434735, and Coprococcus eutactus were more enriched in the ZD group, while probiotic bacteria Bifidobacterium kashiwanohense showed the reverse trend. The functional profile of intestinal flora was also under the influence of zinc deficiency, as reflected by higher levels of various glycoside hydrolases in the ZD group. In addition, saccharin, the pro-inflammatory metabolites, and taurocholic acid, the potential factor inducing intestinal leakage, were higher in the ZD group. In conclusion, zinc deficiency may disturb the gut microbiome community and metabolic function profile of school-age children, potentially affecting human health.

Potential effects of nutrition-induced alteration of gut microbiota on inflammatory bowel disease: A review

Inflammatory bowel disease (IBD), mainly comprising ulcerative colitis and Crohn's disease, is a group of gradually progressive diseases bringing significant mental anguish and imposes serious economic burdens. Interplay of genetic, environmental, and immunological factors have been implicated in its pathogenesis. Nutrients, as crucial environmental determinants, mainly encompassing carbohydrates, fats, proteins, and micronutrients, are closely related to the pathogenesis and development of IBD. Nutrition is essential for maintaining the dynamic balance of intestinal eco-environments to ensure intestinal barrier and immune homeostasis, while this balance can be disrupted easily by maladjusted nutrition. Research has firmly established that nutrition has the potential to shape the composition and function of gut microbiota to affect the disease course. Unhealthy diet and eating disorders lead to gut microbiota dysbiosis and further destroy the function of intestinal barrier such as the disruption of membrane integrity and increased permeability, thereby triggering intestinal inflammation. Notably, appropriate nutritional interventions, such as the Mediterranean diet, can positively modulate intestinal microecology, which may provide a promising strategy for future IBD prevention. In this review, we provide insights into the interplay between nutrition and gut microbiota and its effects on IBD and present some previously overlooked lines of evidence regarding the role of derived metabolites in IBD processes, such as trimethylamine N-oxide and imidazole propionate. Furthermore, we provide some insights into reducing the risk of onset and exacerbation of IBD by modifying nutrition and discuss several outstanding challenges and opportunities for future study.

Dietary index based on the Food Standards Agency nutrient profiling system and risk of Crohn's disease and ulcerative colitis

BACKGROUND

Nutri-score is now widely available in food packages in Europe.

AIM

To study the overall nutritional quality of the diet in relation to risks of Crohn's disease (CD) and ulcerative colitis (UC), in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort METHODS: We collected dietary data at baseline from validated food frequency questionnaires. We used a dietary index based on the UK Food Standards Agency modified nutrient profiling system (FSAm-NPS-DI) underlying the Nutri-Score label, to measure the nutritional quality of the diet. We estimated the association between FSAm-NPS-DI score, and CD and UC risks using Cox models stratified by centre, sex and age; and adjusted for smoking status, BMI, physical activity, energy intake, educational level and alcohol intake.

RESULTS

We included 394,255 participants (68.1% women; mean age at recruitment 52.1 years). After a mean follow-up of 13.6 years, there were 184 incident cases of CD and 459 incident cases of UC. Risk of CD was higher in those with a lower nutritional quality, that is higher FSAm-NPS-DI Score (fourth vs. first quartile: aHR: 2.04, 95% CI: 1.24-3.36; p-trend: <0.01). Among items of the FSAm-NPS-DI Score, low intakes of dietary fibre and fruits/vegetables/legumes/nuts were associated with higher risk of CD. Nutritional quality was not associated with risk of UC (fourth vs. first quartile of the FSAm-NPS-DI Score: aHR: 0.91, 95% CI: 0.69-1.21; p-trend: 0.76).

CONCLUSIONS

A diet with low nutritional quality as measured by the FSAm-NPS-DI Score is associated with a higher risk of CD but not UC.

Sudden-Onset Acute Obsessive-Compulsive Disorder Associated with Streptococcus and Brain MRI Hyperintensity in a Young Adult

BACKGROUND

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal (strep) infections (PANDAS) are a recognized medical entity among children. But evidence for strep-mediated sudden-onset obsessive-compulsive disorder (OCD) in young adults is very limited. Delayed strep assessment and treatment may negatively impact clinical outcomes.

METHODS

We describe a young adult with acute sudden-onset OCD (age 24), treated unsuccessfully with medication and therapy for 3 years. At age 27, antistreptolysin-O (ASO) was tested, based on extensive pediatric history of strep infections. Antibiotic treatment was initiated.

RESULTS

Magnetic resonance imaging (MRI) identified a new temporal lobe hyperintensity at OCD onset (age 24), which persisted at ages 25 and 30. ASO titers were elevated from age 27 through 29. Following Amoxicillin treatment, ASO initially increased. Subsequent Amoxicillin + Clavulin treatment produced improved OCD symptoms and treatment response, with no adverse effects.

CONCLUSION

These results strongly suggest an association among strep infection, neuro-inflammation and sudden-onset OCD in this young adult whose response to medication and therapy was successful only after high-dose antibiotic intervention. Greater OCD remission potential may be possible with earlier identification and antibiotic treatment than 3 years post OCD onset. These findings add to the limited literature on strep as an etiology of the sudden-onset of OCD in young adults. They also lend urgency to increased frontline awareness for early strep and ASO assessment in sudden-onset acute OCD among young adults.

Dietary Patterns and Risk of Inflammatory Bowel Disease: A Systematic Review of Observational Studies

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing worldwide. Dietary patterns may be associated with odds of this disease. Although previous reviews have attempted to summarize the evidence in this field, the growing body of investigations prompted us to conduct an updated comprehensive systematic review.

METHODS

We used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to evaluate the association between dietary patterns before disease onset and the risk of IBD. PubMed, SCOPUS, and Web of Science were searched using structured keywords up to November 20, 2023.

RESULTS

Twenty-four publications (13 case-control, 1 nested case-control, and 10 cohort studies) were included in this review. The sample size of these studies ranged from 181 to 482 887 subjects. The findings were inconsistent across the included studies, showing inverse, direct, or no association between different dietary patterns and the risk of IBD.

CONCLUSIONS

This review provides comprehensive data on the link between dietary patterns prior to IBD diagnosis and risk of this condition. The explicit finding of present review is the extent gap in our knowledge in this field. Therefore, large-scale, high-quality studies are warranted to improve our understanding of the relationship between dietary patterns and IBD risk.

Zinc Deficiency and Therapeutic Value of Zinc Supplementation in Pediatric Gastrointestinal Diseases

The benefits of zinc in treating certain gastrointestinal (GI) diseases have been recognized for over two decades. This review aims to explore zinc deficiency (ZD) and the potential therapeutic value and safety of zinc supplementation in pediatric GI diseases. A systematic review of published articles on ZD and zinc as adjuvant treatments for GI diseases was conducted using various databases. Children with inflammatory bowel disease (IBD), celiac disease, and those receiving long-term proton pump inhibitor treatments are particularly susceptible to ZD. ZD in children with celiac disease and IBD is attributed to insufficient intake, reduced absorption, and increased intestinal loss as a result of the inflammatory process. Zinc plays a crucial role in maintaining the integrity of the gastric mucosa and exerts a gastroprotective action against gastric lesions. Although considerable evidence supports the use of zinc as adjuvant therapy for certain GI diseases in adults, its use is unspecified in children except for infectious diarrhea. Current evidence suggests that zinc supplementation with well-documented dosages helps reduce the duration of diarrhea in children with acute or persistent diarrhea, while there are no specific guidelines for zinc supplementation in children with IBD and celiac disease. Zinc supplementation appears to be beneficial in peptic ulcer disease or gastroesophageal reflux disease. The available evidence highlights the need for intervention programs to enhance zinc status and reduce the morbidity of certain GI diseases in children.

Food Processing and Risk of Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Several studies have been published on the association between food processing and risks of Crohn's disease (CD) and ulcerative colitis (UC), with some variability in results. We performed a systematic literature review and meta-analysis to study this association.

METHODS

From PubMed, Medline, and Embase until October 2022, we identified cohort studies that studied the association between food processing and the risk of CD or UC. Risk of bias of the included studies was assessed by the Newcastle-Ottawa scale. We computed pooled hazard ratios (HRs) and 95% confidence intervals (CIs) using random-effects meta-analysis based on estimates and standard errors.

RESULTS

A total of 1,068,425 participants were included (13,594,422 person-years) among 5 cohort studies published between 2020 and 2022. Four of the 5 included studies were scored as high quality. The average age of participants ranged from 43 to 56 years; 55%-83% were female. During follow-up, 916 participants developed CD, and 1934 developed UC. There was an increased risk for development of CD for participants with higher consumption of ultra-processed foods compared with those with lower consumption (HR, 1.71; 95% CI, 1.37-2.14; I2 = 0%) and a lower risk of CD for participants with higher consumption of unprocessed/minimally processed foods compared with those with lower consumption (HR, 0.71; 95% CI, 0.53-0.94; I2 = 11%). There was no association between risk of UC and ultra-processed foods (HR, 1.17; 95% CI, 0.86-1.61; I2 = 74%) or unprocessed/minimally processed foods (HR, 0.84; 95% CI, 0.68-1.02; I2 = 0%).

CONCLUSIONS

Higher ultra-processed food and lower unprocessed/minimally processed food intakes are associated with higher risk of CD but not UC.

Micronutrient Status and Prediction of Disease Outcome in Adults With Inflammatory Bowel Disease Receiving Biologic Therapy

BACKGROUND AND AIMS

Micronutrient deficiencies are common in patients with inflammatory bowel disease (IBD), but whether they relate to disease outcomes remains unknown. This study assessed the micronutrient status of adults with IBD on treatment with biologic therapies and explored predictive relationships with disease outcomes.

METHODS

Seventeen micronutrients were measured in the blood of 216 adults with IBD on biologic therapy. Of these, 127 patients (58%) had Crohn's disease (CD), and the majority (70%) received treatment with infliximab. Patients were followed for 12 months and onset of adverse clinical outcomes (eg, requirement for treatment with corticosteroids, hospitalization, or surgical intervention) was recorded, and related to micronutrient status.

RESULTS

Among all patients, the most common deficiencies were for vitamin C (n = 35 of 212 [16.5%]), ferritin (n = 27 of 189 [14.3%]), folate (n = 24 of 171 [14.0%]), and zinc (n = 27 of 210 [12.9%]). During follow-up, 22 (10%) of the 216 patients developed 1 or more adverse clinical outcomes. Patients with CD and zinc deficiency were significantly more likely to require surgery (P = .002) or treatment with corticosteroids (P < .001). In contrast, patients with ulcerative colitis and selenium deficiency were significantly more likely to have a clinical flare of disease (P = .001), whereas those with CD were not. This relationship with selenium remained significant after adjustment for confounders.

CONCLUSIONS

A substantial proportion of adults with IBD present deficiencies for certain micronutrients, with selenium and zinc deficiency predicting adverse disease outcomes. For other micronutrients, deficiencies were less common and should not warrant routine screening. Intervention studies should explore the effect of micronutrient supplementation in modifying disease outcomes in IBD.

Food Processing and Risk of Crohn's Disease and Ulcerative Colitis: A European Prospective Cohort Study

BACKGROUND & AIMS

Industrial foods have been associated with increased risks of several chronic conditions. We investigated the relationship between the degree of food processing and risks of Crohn's disease (CD) and ulcerative colitis (UC) in the European Prospective Investigation into Cancer and Nutrition cohort.

METHODS

Analyses included 413,590 participants (68.6% women; mean baseline age, 51.7 y) from 8 European countries. Dietary data were collected at baseline from validated country-specific dietary questionnaires. Associations between proportions of unprocessed/minimally processed and ultraprocessed food intake and CD and UC risks were estimated using Cox models to obtain hazard ratios (HRs) and 95% CIs. Models were stratified by center, age, and sex, and adjusted for smoking status, body mass index, physical activity, energy intake, educational level, and alcohol consumption.

RESULTS

During a mean follow-up period of 13.2 years, 179 incident cases of CD and 431 incident cases of UC were identified. The risk of CD was lower in people consuming high proportions of unprocessed/minimally processed foods (adjusted HR for the highest vs lowest quartile: 0.57; 95% CI, 0.35-0.93; P trend < .01), particularly fruits and vegetables (adjusted HRs, 0.54; 95% CI, 0.34-0.87 and 0.55; 95% CI, 0.34-0.91, respectively). There was no association between unprocessed/minimally processed food intake and the risk of UC. No association was detected between ultraprocessed food consumption and CD or UC risks.

CONCLUSIONS

In the European Prospective Investigation into Cancer and Nutrition cohort, consumption of unprocessed/minimally processed foods was associated with a lower risk of CD. No association between UC risk and food processing was found.

Drinking water quality and inflammatory bowel disease: a prospective cohort study

Environmental factors, such as drinking water and diets, play an important role in the development of inflammatory bowel disease (IBD). This study aimed to investigate the associations of metal elements and disinfectants in drinking water with the risk of inflammatory bowel disease (IBD) and to assess whether diet influences these associations. We conducted a prospective cohort study including 22,824 participants free from IBD from the Yinzhou cohort study in the 2016-2022 period with an average follow-up of 5.24 years. The metal and disinfectant concentrations were measured in local pipeline terminal tap water samples. Cox regression models adjusted for multi-level covariates were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (95% CIs). During an average follow-up period of 5.24 years, 46 cases of IBD were identified. For every 1 standard deviation (SD) increase in the concentration of manganese, mercury, selenium, sulfur tetraoxide (SO₄)_, chlorine, and nitrate nitrogen (NO₃_N) were associated with a higher risk of IBD with the HRs of 1.45 (95% CI: 1.14 to 1.84), 1.51 (95% CI: 1.24-1.82), 1.29 (95% CI: 1.03-1.61), 1.52 (95% CI: 1.26-1.83), 1.26 (95% CI: 1.18-1.34), and 1.66 (95% CI: 1.32-2.09), whereas zinc and fluorine were inversely associated with IBD with the HRs of 0.42 (95% CI: 0.24 to 0.73) and 0.68 (95% CI: 0.54-0.84), respectively. Stronger associations were observed in females, higher income groups, low education groups, former drinkers, and participants who never drink tea. Diets have a moderating effect on the associations of metal and nonmetal elements with the risk of IBD. We found significant associations between exposure to metals and disinfectants and IBD. Diets regulated the associations to some extent.

Adjunctive therapeutic effects of micronutrient supplementation in inflammatory bowel disease

Growing evidence suggests that micronutrient status may have some impact on the course of inflammatory bowel disease (IBD). However, micronutrient deficiencies are easily overlooked during the treatment of IBD patients. There have been many studies on micronutrient supplementation, in which several clinical trials have been conducted targeting vitamin D and iron, but the current research is still preliminary for other vitamins and minerals. This review provides an overview of the adjunctive therapeutic effects of micronutrient supplementation in IBD, to summarize the available evidence, draw the attention of clinicians to micronutrient monitoring and supplementation in patients with IBD, and also provide some perspectives for future research directions.

A Mendelian Randomization Analysis Investigates Causal Associations between Inflammatory Bowel Diseases and Variable Risk Factors

The question of whether variable risk factors and various nutrients are causally related to inflammatory bowel diseases (IBDs) has remained unanswered so far. Thus, this study investigated whether genetically predicted risk factors and nutrients play a function in the occurrence of inflammatory bowel diseases, including ulcerative colitis (UC), non-infective colitis (NIC), and Crohn's disease (CD), using Mendelian randomization (MR) analysis. Utilizing the data of genome-wide association studies (GWASs) with 37 exposure factors, we ran Mendelian randomization analyses based on up to 458,109 participants. Univariable and multivariable MR analyses were conducted to determine causal risk factors for IBD diseases. Genetic predisposition to smoking and appendectomy as well as vegetable and fruit intake, breastfeeding, n-3 PUFAs, n-6 PUFAs, vitamin D, total cholesterol, whole-body fat mass, and physical activity were related to the risk of UC (p < 0.05). The effect of lifestyle behaviors on UC was attenuated after correcting for appendectomy. Genetically driven smoking, alcohol consumption, appendectomy, tonsillectomy, blood calcium, tea intake, autoimmune diseases, type 2 diabetes, cesarean delivery, vitamin D deficiency, and antibiotic exposure increased the risk of CD (p < 0.05), while vegetable and fruit intake, breastfeeding, physical activity, blood zinc, and n-3 PUFAs decreased the risk of CD (p < 0.05). Appendectomy, antibiotics, physical activity, blood zinc, n-3 PUFAs, and vegetable fruit intake remained significant predictors in multivariable MR (p < 0.05). Besides smoking, breastfeeding, alcoholic drinks, vegetable and fruit intake, vitamin D, appendectomy, and n-3 PUFAs were associated with NIC (p < 0.05). Smoking, alcoholic drinks, vegetable and fruit intake, vitamin D, appendectomy, and n-3 PUFAs remained significant predictors in multivariable MR (p < 0.05). Our results provide new and comprehensive evidence demonstrating that there are approving causal effects of various risk factors on IBDs. These findings also supply some suggestions for the treatment and prevention of these diseases.

Antioxidants, minerals and vitamins in relation to Crohn's disease and ulcerative colitis: A Mendelian randomization study

BACKGROUND

Evidence for antioxidants, minerals and vitamins in relation to the risk of Crohn's disease (CD) and ulcerative colitis (UC) is limited and inconsistent. This mendelian randomization (MR) study aimed to examine the causal associations of circulating levels of antioxidants, minerals and vitamins with CD and UC.

METHODS

Single-nucleotide polymorphisms associated with antioxidants (beta-carotene, lycopene and uric acid), minerals (copper, calcium, iron, magnesium, phosphorus, zinc and selenium), and vitamins (folate, vitamins A, B6, B12, C, D, E and K1) were employed as instrumental variables. Genetic associations with CD and UC were extracted from the UK Biobank, the FinnGen study and the International Inflammatory Bowel Disease Genetics Consortium. The inverse variance weighted method and sensitivity analyses were performed.

RESULTS

Genetically predicted higher lycopene (OR = 0.94, 95% CI: 0.91-0.97), vitamins D (OR = 0.65, 95% CI: 0.54-0.79) and K1 (OR = 0.93, 95% CI: 0.90-0.97) levels were inversely associated with CD risk, whereas genetically predicted higher magnesium (OR = 1.53, 95% CI: 1.23-1.90) levels were positively associated with CD risk. Higher levels of genetically predicted lycopene (OR = 0.91, 95% CI: 0.88-0.95), phosphorus (OR = 0.69, 95% CI: 0.58-0.82), selenium (OR = 0.91, 95% CI: 0.85-0.97), zinc (OR = 0.91, 95% CI: 0.89-0.94), folate (OR = 0.71, 95% CI: 0.56-0.92) and vitamin E (OR = 0.78, 95% CI: 0.69-0.88) were associated with reduced UC risk, whereas genetically predicted high levels of calcium (OR = 1.46, 95% CI: 1.22-1.76) and magnesium (OR = 1.24, 95% CI: 1.03-1.49) were associated with increased risk of UC.

CONCLUSIONS

Our study provided evidence that circulating levels of antioxidants, minerals and vitamins might be causally linked to the development of IBD.

Microbiota Composition in Diverticular Disease: Implications for Therapy

Gut microbiota (GM) composition and its imbalance are crucial in the pathogenesis of several diseases, mainly those affecting the gastrointestinal tract. Colon diverticulosis and its clinical manifestations (diverticular disease, DD) are among the most common digestive disorders in developed countries. In recent literature, the role of GM imbalance in the onset of the different manifestations within the clinical spectrum of DD has been highlighted. This narrative review aims to summarize and critically analyze the current knowledge on GM dysbiosis in diverticulosis and DD by comparing the available data with those found in inflammatory bowel disease (IBD). The rationale for using probiotics to rebalance dysbiosis in DD is also discussed.

Advances in understanding of effects of dietary nutrients in inflammatory bowel disease patients

The occurrence of inflammatory bowel disease (IBD) is influenced by environmental factors. Diet, as an important environmental factor, is closely associated with intestinal ecology and plays a critical role in the pathological process of IBD. This review summarizes the role of major dietary nutrients in the pathogenesis of IBD, with an aim to provide clues for the prevention and treatment of IBD.

Mediterranean-Like Dietary Pattern Associations With Gut Microbiome Composition and Subclinical Gastrointestinal Inflammation

BACKGROUND & AIMS

Case-control studies have shown that patients with Crohn's disease (CD) have a microbial composition different from healthy individuals. Although the causes of CD are unknown, epidemiologic studies suggest that diet is an important contributor to CD risk, potentially via modulation of bacterial composition and gut inflammation. We hypothesized that long-term dietary clusters (DCs) are associated with gut microbiome compositions and gut inflammation. Our objectives were to identify dietary patterns and assess whether they are associated with alterations in specific gut microbial compositions and subclinical levels of gut inflammation in a cohort of healthy first-degree relatives (FDRs) of patients with CD.

METHODS

As part of the Genetic, Environmental, Microbial (GEM) Project, we recruited a cohort of 2289 healthy FDRs of patients with CD. Individuals provided stool samples and answered a validated food frequency questionnaire reflecting their habitual diet during the year before sample collection. Unsupervised analysis identified 3 dietary and 3 microbial composition clusters.

RESULTS

DC3, resembling the Mediterranean diet, was strongly associated with a defined microbial composition, with an increased abundance of fiber-degrading bacteria, such as Ruminococcus, as well as taxa such as Faecalibacterium. The DC3 diet was also significantly associated with lower levels of subclinical gut inflammation, defined by fecal calprotectin, compared with other dietary patterns. No significant associations were found between individual food items and fecal calprotectin, suggesting that long-term dietary patterns rather than individual food items contribute to subclinical gut inflammation. Additionally, mediation analysis demonstrated that DC3 had a direct effect on subclinical inflammation that was partially mediated by the microbiota.

CONCLUSIONS

Overall, these results indicated that Mediterranean-like dietary patterns are associated with microbiome and lower intestinal inflammation. This study will help guide future dietary strategies that affect microbial composition and host gut inflammation to prevent diseases.

Meat Intake Is Associated with a Higher Risk of Ulcerative Colitis in a Large European Prospective Cohort Studyø

BACKGROUND AND AIMS

We aimed to investigate the association between protein intake and risk of inflammatory bowel disease [IBD] in the European Prospective Investigation into Cancer and Nutrition.

METHODS

A total of 413 593 participants from eight European countries were included. Dietary data were collected at baseline from validated food frequency questionnaires. Dietary data were calibrated to correct errors in measures related to each country-specific questionnaire. Associations between proteins [total, animal, and vegetable] or food sources of animal proteins, and IBD risk were estimated by Cox proportional hazard models.

RESULTS

After a mean follow-up of 16 years, 177 patients with Crohn's disease [CD] and 418 with ulcerative colitis [UC], were identified. There was no association between total protein, animal protein, or vegetable protein intakes and CD or UC risks. Total meat and red meat intakes were associated with UC risk (hazard ratio [HR] for the 4th vs 1st quartile = 1.40, 95% confidence interval [CI] = 0.99-1.98, p-trend = 0.01; and 1.61, 95% CI = 1.10-2.36, p-trend = 0.007, respectively]. There was no association between other food sources of animal protein [processed meat, fish, shellfish, eggs, poultry] and UC. We found no association between food sources of animal proteins and CD risk.

CONCLUSIONS

Meat and red meat consumptions are associated with higher risks of UC. These results support dietary counselling of low meat intake in people at high-risk of IBD.

Diet as a treatment for inflammatory bowel disease: is it ready for prime time?

PURPOSE OF REVIEW

Diet remains an important topic for patients with inflammatory bowel disease (IBD), yet few guidelines for dietary recommendations exist. There is a growing interest in the use of diet as treatment or adjuvant therapy for both ulcerative colitis and Crohn's disease. Here, we highlight the latest evidence on the use of diet for treatment of symptoms, active disease and maintenance of remission in ulcerative colitis and Crohn's disease.

RECENT FINDINGS

The Crohn's Disease Exclusion Diet (CDED) and the Specific Carbohydrate Diet (SCD) are studied diets that have gained popularity, but there is growing interest in the use and efficacy of less restrictive diets such as the Mediterranean diet. Recent data suggest healthful dietary patterns alone, with an emphasis on whole foods that are high in vegetable fibre and that promote less consumption of ultra-processed foods may also help achieve remission in patients with ulcerative colitis and Crohn's disease.

SUMMARY

In this review, we summarize the literature on diet as treatment for IBD. We highlight the latest clinical dietary studies, randomized clinical trials, as well as new and emerging diets for the treatment of IBD.

The Impact of Zinc and Zinc Homeostasis on the Intestinal Mucosal Barrier and Intestinal Diseases

Zinc is an essential trace element for living organisms, and zinc homeostasis is essential for the maintenance of the normal physiological functions of cells and organisms. The intestine is the main location for zinc absorption and excretion, while zinc and zinc homeostasis is also of great significance to the structure and function of the intestinal mucosal barrier. Zinc excess or deficiency and zinc homeostatic imbalance are all associated with many intestinal diseases, such as IBD (inflammatory bowel disease), IBS (irritable bowel syndrome), and CRC (colorectal cancer). In this review, we describe the role of zinc and zinc homeostasis in the intestinal mucosal barrier and the relevance of zinc homeostasis to gastrointestinal diseases.

Crohn's Disease and Female Infertility: Can Nutrition Play a Supporting Role?

Crohn's disease (CD) is a chronic inflammatory disease (IBD) that can affect the entire gastrointestinal tract in a non-continuous mode. CD is generally diagnosed most commonly between 15 and 35 years of age and may affect female fertility. The role of diet in supporting wellbeing outcome and reproductive potential in women is well-known; however, no effective efforts have been made to improve women's awareness in CD. Our review aims to describe the burden of CD on women's fertility, reporting the most relevant nutrients that support reproductive function to ensure women diagnosed with IBD an adequate health-related quality of life.

Nutraceuticals and Diet Supplements in Crohn's Disease: A General Overview of the Most Promising Approaches in the Clinic

Crohn's disease (CD) is a chronic inflammatory gastrointestinal disorder requiring lifelong medications. The currently approved drugs for CD are associated with relevant side effects and several studies suggest an increased use of nutraceuticals among CD patients, seeking for what is perceived as a more "natural" approach in controlling this highly morbid condition. Nutraceuticals are foods or foods' components with beneficial health properties that could aid in CD treatment for their anti-inflammatory, analgesic and immunoregulatory activities that come along with safety, high tolerability, easy availability and affordability. Depending on their biological effect, nutraceuticals' support could be employed in different subsets of CD patients, both those with active disease, as adjunctive immunomodulatory therapies, and/or in quiescent disease to provide symptomatic relief in patients with residual functional symptoms. Despite the increasing interest of the general public, both limited research and lack of education from healthcare professionals regarding their real clinical effectiveness account for the increasing number of patients turning to unconventional sources. Professionals should recognize their widespread use and the evidence base for or against their efficacy to properly counsel IBD patients. Overall, nutraceuticals appear to be safe complements to conventional therapies; nonetheless, little quality evidence supports a positive impact on underlying inflammatory activity.

Clonal cytopenia of undetermined significance and atypical Behçet's: the importance of zinc

Atypical Behçet's is recognised in myelodysplastic syndrome (MDS) cases and is associated with trisomy 8. Clonal cytopenia of undetermined significance (CCUS) is recognised as a precursor to MDS. Our case describes the presentation of atypical Behçet's, in association with CCUS, post a Streptococcal infection. A mutation of a zinc finger RNA spliceosome, ZRSR2, is also described. Our patient initially presented with macrocytic anaemia, together with neutropenia and lymphocytopenia on routine monitoring. Later gastrointestinal symptoms together with oral and anal ulcerations developed. He was treated with oral zinc therapy and had resolution of recurrent oral ulcerations and significant reduction in severity of anal ulcerations. The functional impact of ZRSR2 mutation on spliceosome assembly is yet to be defined, but has been previously reported in CCUS with a clinical phenotype of macrocytic anaemia.

Zinc Exposure Promotes Commensal-to-Pathogen Transition in Pseudomonas aeruginosa Leading to Mucosal Inflammation and Illness in Mice

The opportunistic pathogen Pseudomonas aeruginosa (P. aeruginosa) is associated gastrointestinal (GI) inflammation and illness; however, factors motivating commensal-to-pathogen transition are unclear. Excessive zinc intake from supplements is common in humans. Due to the fact that zinc exposure enhances P. aeruginosa colonization in vitro, we hypothesized zinc exposure broadly activates virulence mechanisms, leading to inflammation and illness. P. aeruginosa was treated with excess zinc and growth, expression and secretion of key virulence factors, and biofilm production were determined. Effects on invasion, barrier function, and cytotoxicity were evaluated in Caco-2 cells co-cultured with P. aeruginosa pre-treated with zinc. Effects on colonization, mucosal pathology, inflammation, and illness were evaluated in mice infected with P. aeruginosa pre-treated with zinc. We found the expression and secretion of key virulence factors involved in quorum sensing (QS), motility (type IV pili, flagella), biosurfactants (rhamnolipids), toxins (exotoxin A), zinc homeostasis (CzcR), and biofilm production, were all significantly increased. Zinc exposure significantly increased P. aeruginosa invasion, permeability and cytotoxicity in Caco-2 cells, and enhanced colonization, inflammation, mucosal damage, and illness in mice. Excess zinc exposure has broad effects on key virulence mechanisms promoting commensal-to-pathogen transition of P. aeruginosa and illness in mice, suggesting excess zinc intake may have adverse effects on GI health in humans.

Zinc and Selenium in Inflammatory Bowel Disease: Trace Elements with Key Roles?

Inflammatory bowel disease (IBD) is a chronic inflammatory condition that may emerge at a young age and often lasts for life. It often goes through phases of recurrence and remission and has a devastating effect on quality of life. The exact etiology of the disease is still unclear, but it appears that an inappropriate immune response to intestinal flora bacteria in people with a genetic predisposition may cause the disease. Managing inflammatory bowel disease is still a serious challenge. Oxidative stress and free radicals appear to be involved in the pathogenesis of this disease, and a number of studies have suggested the use of antioxidants as a therapeutic approach. The antioxidant and anti-inflammatory properties of some trace elements have led some of the research to focus on studying these trace elements in inflammatory bowel disease. Zinc and selenium are among the most important trace elements that have significant anti-inflammatory and antioxidant properties. Some studies have shown the importance of these trace elements in inflammatory bowel disease. In this review, we have attempted to provide a comprehensive overview of the findings of these studies and to gather current knowledge about the association of these trace elements with the inflammatory process and inflammatory bowel disease.

Diet-Microbiota Interactions in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract. Although the precise etiology of IBD is largely unknown, it is widely thought that diet contributes to the development of IBD. Diet shapes the composition of the gut microbiota, which plays critical roles in intestinal homeostasis. In contrast, intestinal inflammation induces gut dysbiosis and may affect the use of dietary nutrients by host cells and the gut microbiota. The interaction of diet and the gut microbiota is perturbed in patients with IBD. Herein, we review the current knowledge of diet and gut microbiota interaction in intestinal homeostasis. We also discuss alterations of diet and gut microbiota interaction that influence the outcome and the nutritional treatment of IBD. Understanding the complex relationships between diet and the gut microbiota provides crucial insight into the pathogenesis of IBD and advances the development of new therapeutic approaches.

Inflammatory Bowel Diseases: Is There a Role for Nutritional Suggestions?

Nutrition has an important impact on inflammatory bowel diseases (IBD). In particular, several studies have addressed its role in their pathogenesis, showing how the incidence of IBD significantly increased in recent years. Meanwhile, nutrition should be considered a component of the treatment of the disease, both as a therapy itself, and especially in the perspective of correcting the various nutritional deficiencies shown by these patients. In this perspective, nutritional suggestions are very important even in the most severe forms of IBD, requiring hospitalization or surgical treatment. Although current knowledge about nutrition in IBD is increasing over time, nutritional suggestions are often underestimated by clinicians. This narrative review is an update summary of current knowledge on nutritional suggestions in IBD, in order to address the impact of nutrition on pathogenesis, micro- and macro-nutrients deficiencies (especially in the case of sarcopenia and obesity), as well as in hospitalized patients.

The Prevalence of Zinc Deficiency in Crohn's Disease Patients

Objective: Zinc is a trace element, which has been related to inflammatory diseases such as inflammatory bowel disease (IBD). We aimed to evaluate the serum zinc levels in Iranian patients with Crohn's disease (CD). Materials and methods:The present study was conducted on 65 CD patients and 65 healthy controls. Serum zinc levels were measured in both patients and controls and compared by age, sex, and site of inflammation between groups. Results: Mean serum zinc level in the study population was 86.2±17.0 ng/dL. The serum zinc level was 88.1±16.7 ng/dL in CD patients and 86.2±17.0 ng/dL in the control group. The difference between groups was not statistically significant (P=0.191). No significant differences were observed in serum zinc levels of males and females (P=0.087). Zinc deficiency was observed in 21.5% and 7.7% of cases and controls, respectively. Compared to the control group, low serum zinc levels were significantly higher in CD patients (P=0.025). Regarding the site of inflammation, neither the concentration of serum zinc (P=0.058) nor zinc deficiency prevalence (P=0.864) were significantly different in cases compared to controls. Conclusion: The prevalence of zinc deficiency was higher in CD patients compared to controls. However, serum zinc concentrations were not significantly different between groups. Age, sex, and site of inflammation were not found to be predictors of zinc deficiency. Evaluating the zinc status of CD patients for possible supplementation in cases of deficiency is recommended.

Nutrition in the Management of Inflammatory Bowel Diseases

With the increasing global prevalence of inflammatory bowel diseases, research in this field is expanding to better understand the multifactorial etiologies of this complex disease. Nutrition and diet, as modifiable risk factors, have been shown to play an important role in disease activity and prognosis. This article reviews the role of nutrition in inflammatory bowel disease, including appropriate nutrition screening in this at-risk population, and associated micronutrient deficiencies. We provide recommendations on dosing supplementation. We briefly review diet as a risk factor for inflammatory bowel disease and the currently proposed published dietary intervention studies.

Dietary Patterns, Ultra-processed Food, and the Risk of Inflammatory Bowel Diseases in the NutriNet-Santé Cohort

BACKGROUND

The incidence of inflammatory bowel diseases (IBDs) tended to increase for several decades. Diet is suspected to be a major determinant of the occurrence of these diseases. This prospective study aimed to assess the associations among occurrence of IBD, dietary patterns, and ultra-processed food in the French NutriNet-Santé cohort.

METHODS

Participants of the NutriNet-Santé cohort who completed at least three 24-hour dietary records were included. Incident IBD cases were identified from 3 questionnaires and confirmed by phone or email interview. Major dietary patterns (DPs) were computed using a principal component analysis (PCA) based on 29 food groups' consumption, whereas proportions of ultra-processed foods (UPFs) were obtained using the NOVA classification. Multivariable Poisson models were performed to evaluate associations among DP quintiles, UPF proportion (UPFp) in the diet, and incident IBD.

RESULTS

A total of 105,832 participants were included, contributing 238,924 person-years in a mean follow-up of 2.3 ± 2.2 years. Among them, 75 participants reported an incident IBD. Three major DPs were retained: "healthy," "traditional," and "western." No significant association was found for DPs and UPFp after adjustments for covariates.

CONCLUSIONS

In this study, neither DPs nor UPF proportion in the diet were significantly associated with the risk of incident IBD after adjustments for covariates. Further studies are needed to investigate the long-term association between diet and IBD.

The Role of Diet in the Pathogenesis and Management of Inflammatory Bowel Disease: A Review

Inflammatory bowel diseases, which include ulcerative colitis and Crohn’s disease, are chronic relapsing and remitting inflammatory diseases of the gastrointestinal tract that are increasing in prevalence and incidence globally. They are associated with significant morbidity, reduced quality of life to individual sufferers and are an increasing burden on society through direct and indirect costs. Current treatment strategies rely on immunosuppression, which, while effective, is associated with adverse events. Epidemiological evidence suggests that diet impacts the risk of developing IBD and modulates disease activity. Using diet as a therapeutic option is attractive to patients and clinicians alike due to its availability, low cost and few side effects. Diet may influence IBD risk and disease behaviour through several mechanisms. Firstly, some components of the diet influence microbiota structure and function with downstream effects on immune activity. Secondly, dietary components act to alter the structure and permeability of the mucosal barrier, and lastly dietary elements may have direct interactions with components of the immune response. This review will summarise the mechanisms of diet–microbial–immune system interaction, outline key studies examining associations between diet and IBD and evidence demonstrating the impact of diet on disease control. Finally, this review will outline current prescribed dietary therapies for active CD.

Increase in Epithelial Permeability and Cell Metabolism by High Mobility Group Box 1, Inflammatory Cytokines and TPEN in Caco-2 Cells as a Novel Model of Inflammatory Bowel Disease

High mobility group box 1 protein (HMGB1) is involved in the pathogenesis of inflammatory bowel disease (IBD). Patients with IBD develop zinc deficiency. However, the detailed roles of HMGB1 and zinc deficiency in the intestinal epithelial barrier and cellular metabolism of IBD remain unknown. In the present study, Caco-2 cells in 2D culture and 2.5D Matrigel culture were pretreated with transforming growth factor-β (TGF-β) type 1 receptor kinase inhibitor EW-7197, epidermal growth factor receptor (EGFR) kinase inhibitor AG-1478 and a TNFα antibody before treatment with HMGB1 and inflammatory cytokines (TNFα and IFNγ). EW-7197, AG-1478 and the TNFα antibody prevented hyperpermeability induced by HMGB1 and inflammatory cytokines in 2.5D culture. HMGB1 affected cilia formation in 2.5D culture. EW-7197, AG-1478 and the TNFα antibody prevented the increase in cell metabolism induced by HMGB1 and inflammatory cytokines in 2D culture. Furthermore, ZnSO₄ prevented the hyperpermeability induced by zinc chelator TPEN in 2.5D culture. ZnSO₄ and TPEN induced cellular metabolism in 2D culture. The disruption of the epithelial barrier induced by HMGB1 and inflammatory cytokines contributed to TGF-β/EGF signaling in Caco-2 cells. The TNFα antibody and ZnSO₄ as well as EW-7197 and AG-1478 may have potential for use in therapy for IBD.

Crohn's Disease: Is the Cold Chain Hypothesis Still Hot?

Crohn's disease [CD] is an inflammatory bowel disease of unknown aetiology. During recent decades, significant technological advances led to development of -omic datasets allowing a detailed description of the disease. Unfortunately these have not, to date, resolved the question of the aetiology of CD. Thus, it may be necessary to [re]consider hypothesis-driven approaches to resolve the aetiology of CD. According to the cold chain hypothesis, the development of industrial and domestic refrigeration has led to frequent exposure of human populations to bacteria capable of growing in the cold. These bacteria, at low levels of exposure, particularly those of the genus Yersinia, are believed to be capable of inducing exacerbated inflammation of the intestine in genetically predisposed subjects. We discuss the consistency of this working hypothesis in light of recent data from epidemiological, clinical, pathological, microbiological, and molecular studies.

Arjunarishta alleviates experimental colitis via suppressing proinflammatory cytokine expression, modulating gut microbiota and enhancing antioxidant effect

Traditional ayurvedic medicine, Arjunarishta (AA) is used to treat several inflammatory conditions including dysentery associated with blood. The formulation is a decoction of Terminalia arjuna (Roxb.) Wight and Arn. (TA), Madhuca indica J.F.Gmel., Vitis vinifera L., Woodfordia fruticosa (L.) Kurz., and Saccharum officinarum L. Terminalia arjuna, a major constituent of this formulation has been recognized for anti-inflammatory effects. This study aimed at evaluating beneficial effects of AA and probable mechanism of action in Trinitrobenzenesulphonicacid (TNBS) induced colitis model. Response to AA treatment was explored through determination of disease activity index (DAI), histological assessment and damage scores, colonic pro-inflammatory cytokine/chemokine expression and estimation of oxidative stress biomarkers. Improvement in gut microbiome and plasma zinc level was also assessed. Study findings directed therapeutic effects of AA treatment in colitis model by attenuating the colitis symptoms such as weight loss, diarrhoea, blood in stool; histological damage; and downregulated expression of pro-inflammatory cytokines/chemokine (TNF-α, IL-1β, IL-6) and MCP-1). Similarly reduced oxidative stress by decreased level of Nitric Oxide (NO), Myeloperoxidase (MPO), Malondialdehyde (MDA) and enhanced level of Catalase (CAT), Superoxide dismutase (SOD) and Reduced Glutathione (GSH) was also witnessed. In addition, an improved beneficial fecal microbiome profile and restored plasma zinc status was revealed compared to the TNBS control group. The present study directs that downregulated pro-inflammatory cytokines/chemokine expression, enhancement of antioxidant effect, increased plasma zinc status and promising role in modulating fecal microbiome might be potential mechanisms for the therapeutic effect of AA treatment against colitis.

Dietary Zinc Intake and Inflammatory Bowel Disease in the French NutriNet-Santé Cohort

INTRODUCTION

This study aimed to assess the association between incident Crohn's disease (CD) or incident ulcerative colitis (UC) and dietary zinc intake.

METHODS

NutriNet-Santé cohort's participants who completed at least three 24-hour dietary records were included and incident CD or UC cases were identified. Multivariable Poisson models were performed to assess associations between tertiles of zinc intake and CD or UC.

RESULTS

Among the 105,832 participants, 27 reported incident CD and 48 reported incident UC. The relative risks of CD decreased with dietary zinc intakes. Compared with participants with the lowest tertile of zinc intake, the relative risks for CD were 0.60 (95% confidence interval [0.22-1.66]) and 0.12 (95% confidence interval [0.02-0.73]) for the second and the highest tertiles, respectively (Ptrend = 0.02). No significant association was observed for UC.

DISCUSSION

Dietary zinc intake was inversely associated with incident CD.

Zinc Deficiency Activates the IL-23/Th17 Axis to Aggravate Experimental Colitis in Mice

BACKGROUND AND AIMS

Patients with inflammatory bowel disease [IBD], especially Crohn's disease, often develop zinc deficiency. However, the precise mechanisms by which zinc deficiency affects IBD pathology, particularly intestinal macrophage function, remain unclear. We studied the effects of zinc deficiency on the development and progression of colitis in mice.

METHODS

To induce colitis, mice were treated with 2,4,6-trinitrobenzene sulphonic acid. Rag1-/- mice were then given injections of naïve CD4+CD62L+ T cells. The respective degrees of mucosal injury of mice that had received a zinc chelator (TPEN; N,N,N',N'-tetrakis [2-pyridylmethyl]ethylenediamine) and of control mice were subsequently compared. Colonic lamina propria mononuclear cells were isolated by enzymatic digestion and were examined using flow cytometry. To generate mouse bone marrow-derived macrophages [BMDMs], bone marrow cells were stimulated with mouse macrophage-colony stimulating factor.

RESULTS

Zinc deficiency aggravates colonic inflammation through the activation of type 17 helper T [Th17] cells in mice. Flow cytometric analysis revealed that zinc deficiency significantly increases the proportion of pro-inflammatory [M1] macrophages in colonic lamina propria mononuclear cells obtained from inflamed colon. Interferon-γ plus lipopolysaccharide-mediated M1 skewing alters the expression of zinc transporters in BMDMs and thereby decreases the intracellular free zinc. TPEN treatment mimicking the effects of the M1 skewing up-regulates IL-23p19 expression, which is strongly related to Th17 development. Furthermore, the nuclear accumulation of interferon-regulatory factor 5 is closely involved in IL-23p19 induction in zinc-deficient macrophages.

CONCLUSIONS

Zinc deficiency aggravates colonic inflammation through activation of the IL-23/Th17 axis. This activation is controlled by subcellular distribution of interferon-regulatory factor 5.

Decreased serum zinc concentration in dogs with lymphocytic-plasmacytic enteritis, and its associations with disease severity and prognosis

Human patients with inflammatory bowel disease may have poor prognosis with hypozincemia. However, there are limited data on zinc concentrations in the blood of dogs with lymphocytic-plasmacytic enteritis (LPE). The purpose of this study was to investigate the serum zinc concentration in dogs with LPE and its influence on disease severity and prognosis. Thirty-five dogs with LPE were recruited. Serum zinc concentration was measured using atomic absorption spectrometry. Hypozincemia was observed in 18/35 (51%) dogs with LPE. Serum zinc concentration was inversely correlated with histological and clinical severities. Overall survivals were significantly shorter in dogs with hypozincemia than in those without it. These findings suggest that serum zinc concentration is a useful biomarker for LPE severity and prognosis in dogs.

A food pyramid, based on a review of the emerging literature, for subjects with inflammatory bowel disease

Emerging literature suggests that diet plays an important modulatory role in inflammatory bowel disease (IBD) through the management of inflammation and oxidative stress. The aim of this narrative review is to evaluate the evidence collected up till now regarding optimum diet therapy for IBD and to design a food pyramid for these patients. The pyramid shows that carbohydrates should be consumed every day (3 portions), together with tolerated fruits and vegetables (5 portions), yogurt (125ml), and extra virgin olive oil; weekly, fish (4 portions), white meat (3 portions), eggs (3 portions), pureed legumes (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: the red one means that subjects with IBD need some personalized supplementation and the black one means that there are some foods that are banned. The food pyramid makes it easier for patients to decide what they should eat.

Paneth cell α-defensin misfolding correlates with dysbiosis and ileitis in Crohn's disease model mice

This study provides novel insight into Crohn’s disease where α-defensin misfolding resulting from excessive ER stress in Paneth cells induces dysbiosis and disease progression.

Crohn’s disease (CD) is an intractable inflammatory bowel disease, and dysbiosis, disruption of the intestinal microbiota, is associated with CD pathophysiology. ER stress, disruption of ER homeostasis in Paneth cells of the small intestine, and α-defensin misfolding have been reported in CD patients. Because α-defensins regulate the composition of the intestinal microbiota, their misfolding may cause dysbiosis. However, whether ER stress, α-defensin misfolding, and dysbiosis contribute to the pathophysiology of CD remains unknown. Here, we show that abnormal Paneth cells with markers of ER stress appear in SAMP1/YitFc, a mouse model of CD, along with disease progression. Those mice secrete reduced-form α-defensins that lack disulfide bonds into the intestinal lumen, a condition not found in normal mice, and reduced-form α-defensins correlate with dysbiosis during disease progression. Moreover, administration of reduced-form α-defensins to wild-type mice induces the dysbiosis. These data provide novel insights into CD pathogenesis induced by dysbiosis resulting from Paneth cell α-defensin misfolding and they suggest further that Paneth cells may be potential therapeutic targets.

The Influence of Nutrients on Inflammatory Bowel Diseases

Inflammatory bowel diseases is a group of inflammatory diseases. The pathogenesis of diseases is multifactorial, which may include a Western-type diet. Diseases occur with periods of recurrence and remission. Many factors can have a beneficial effect on reducing the frequency of recurrence and prolonging the remission period. Such ingredients include dietary fibre, mono- and polyunsaturated fatty acids, certain vitamins (D, C, and E), flavonoids, and minerals such as zinc and selenium. Properly selected nutrition might be an integral part of the treatment of patients with Crohn's disease or ulcerative colitis.

Allergic and Immunologic Perspectives of Inflammatory Bowel Disease

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