Influence of food and lifestyle on the risk of developing inflammatory bowel disease

CCR6–CCL20-Mediated Immunologic Pathways in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) has evoked significant interest in human immunobiology given its tactical immune evasion methodologies resulting in acute immune destabilization. IBD comprising Crohn’s disease and Ulcerative colitis manifests as chronic inflammation in the gut mucosa, leading to complexities involving immune dysregulation in the T helper lymphocyte arm, effecting disease pathogenicity. The mucosa of the alimentary canal is constantly exposed to a myriad of food antigens and luminal microorganisms for which a consistent host-protective mechanism is operative in healthy people. Lowered mucosal immune expression which allows penetration of the epithelial barrier by infective pathogenic microbes elicits both innate and adaptive immune responses in the gut, culminating in aberrant intestinal inflammation. Interestingly, the IBD leukocyte repertoire is significantly entwined with chemokine-assisted chemotactic navigation into the sites of inflammation, which is also thought to generate favorable immune-suppressive responses. The functions of the cognate chemokine receptor, CCR6, which binds with its unique ligand CCL20, are expected to tilt the balance between upregulation of homeostatic tolerance and inflammatory pathophysiology. This review aims to critically examine the CCR6-driven immune pathways: TH1/TH2, TH1/TH17, TH17/Treg, IL-23/IL-17, Akt/ERK-1/2, ILC3, and TH9/TH2 for systematic investigation of its underlying mechanisms in the future and to underpin its importance in resolving IBD pathology. Thus, CCR6 occupies an exclusive position in gut immunology which renders it an invaluable therapeutic tool for the production of novel medicaments to treat IBD.

Differences in adiposity and diet quality among individuals with inflammatory bowel disease in Eastern Canada

The objective of the current study was to characterize the relationship between diet quality and body composition in participants living with IBD, specifically Crohn’s disease (CD) or ulcerative colitis (UC), in Atlantic Canada. Participants from the Atlantic Partnership for Tomorrow’s Health (PATH) study are residents of one of the four Atlantic Canada provinces. Participants who completed the dietary questionnaire and had body composition measured were included in the study (n = 12,462 without IBD, n = 111 CD, n = 119 UC). A greater number of participants with IBD reported having multiple chronic conditions compared to those without IBD. Those with UC had statistically higher body weight and body mass index (BMI) compared to those without IBD. Overall, significant positive correlations were observed between adiposity and servings of refined grains, and meats and alternatives such as eggs and fish, whereas negative correlations were observed with servings of vegetables, fruit, whole grains, and alternatives such as tofu, and nuts/seeds. Participants with IBD (both CD and UC) consumed more refined grains than those without IBD. Using logistic regression analysis, participants consuming more servings of vegetables and whole grains were less likely to have CD where as those consuming more serving of fruit and bean/legumes were less likely to have UC. In the Atlantic PATH cohort, which includes a region of the world with a high incidence of IBD, distinct differences in adiposity and diet quality were observed in individuals with specific types of IBD compared to those without. There is a need for collaborative efforts to address weight management and diet quality issues in those living with IBD in the Atlantic Canadian region.

Helminth Therapy: Advances in the use of Parasitic Worms Against Inflammatory Bowel Diseases and its Challenges

Development of modern medicine and better living conditions in the 20th century helped in reducing a number of cases of infectious diseases. During the same time, expansion of autoimmunological disorders was noticed. Among other are Inflammatory Bowel Diseases (IBD) including ulcerative colitis and Crohn's disease which are chronic and relapsing inflammation of the gastrointestinal tract. Absence of effective treatment in standard therapies effects the search for alternative opportunities. As per hygienic hypothesis increasing number of cases of autoimmune diseases is as a result of reduced exposure to pathogens, especially parasites. Thus, one of the promising remedial acts against IBD and other allergic and autoimmune disorders is "helminth therapy". Cure with helminths seems to be the most effective therapy of IBD currently proposed. Helminth therapy focuses on advantageous results that have been obtained from the clinical trials, but its mechanisms are still unclear. Explanation of this phenomenon would help to develop new drugs against IBD based on helminth immunomodulatory molecules.

Antibiotic Use and New-Onset Inflammatory Bowel Disease in Olmsted County, Minnesota: A Population-Based Case-Control Study

BACKGROUND AND AIMS

Several studies have suggested significant associations between environmental factors and the risk of developing inflammatory bowel disease [IBD]. However, data supporting the role of antibiotics are conflicting. The aim of this study was to evaluate the association between antibiotic use and new-onset IBD.

METHODS

We conducted a population-based case-control study using the Rochester Epidemiology Project of Olmsted County, Minnesota. We identified 736 county residents diagnosed with IBD between 1980 and 2010 who were matched to 1472 controls, based on age, sex and date of IBD diagnosis. Data on antibiotic use between 3 months and 5 years before IBD diagnosis were collected. Logistic regression models were used to estimate associations between antibiotic use and IBD, and were expressed as adjusted odds ratio [AOR] with 95% confidence interval [CI].

RESULTS

Antibiotic use occurred in 455 IBD cases [61.8%] and 495 controls [33.6%] [p < 0.001]. In multivariate analysis, there were statistically significant associations between antibiotic use and new-onset IBD [AOR, 2.93; 95% CI, 2.40-3.58], Crohn's disease [CD] [AOR, 3.01; 2.27-4.00] and ulcerative colitis [UC] [AOR, 2.94; 95% CI, 2.23-3.88]. A cumulative duration of antibiotic use ≥ 30 days had the strongest AOR [6.01; 95% CI, 4.34-8.45]. AOR for those receiving antibiotics under the age of 18 years was 4.27 [95% CI, 2.39-7.91], 2.97 for age 18-60 years [2.36-3.75] and 2.72 for age > 60 years [1.60-4.67].

CONCLUSIONS

This population-based case-control study suggests a strong association between antibiotic use and the risk of both new-onset CD and new-onset UC. The risk was increased among all age-onset IBD.

Genetic polymorphisms associated with smoking behaviour predict the risk of surgery in patients with Crohn's disease

BACKGROUND

Smoking is a strong environmental factor leading to adverse outcomes in Crohn's disease, but a more benign course in ulcerative colitis. Several single nucleotide polymorphisms (SNPs) are associated with smoking quantity and behaviour.

AIM

To assess whether smoking-associated SNPs interact with smoking to influence the clinical course of inflammatory bowel diseases.

METHODS

Genetic and prospectively obtained clinical data from 1434 Swiss inflammatory bowel disease cohort patients (821 Crohn's disease and 613 ulcerative colitis) were analysed. Six SNPs associated with smoking quantity and behaviour (rs588765, rs1051730, rs1329650, rs4105144, rs6474412 and rs3733829) were combined to form a risk score (range: 0-12) by adding the number of risk alleles. We calculated multivariate models for smoking, risk of surgery, fistula, Crohn's disease location and ulcerative colitis disease extent.

RESULTS

In Crohn's disease patients who smoke, the number of surgeries was associated with the genetic risk score. This translates to a predicted 3.5-fold (95% confidence interval: 2.4- to 5.7-fold, P<.0001) higher number of surgical procedures in smokers with 12 risk alleles than individuals with the lowest risk. Patients with a risk score >7 had a significantly shorter time to first intestinal surgery. The genetic risk score did not predict surgery in ulcerative colitis or occurrence of fistulae in Crohn's disease. SNP rs6265 was associated with ileal disease in Crohn's disease (P<.05) and proctitis in ulcerative colitis (P<.05).

CONCLUSIONS

SNPs associated with smoking quantity is associated with an increased risk for surgery in Crohn's disease patients who smoke. Our data provide an example of genetics interacting with the environment to influence the disease course of inflammatory bowel disease.

Microbiome, pattern recognition receptor function in health and inflammation

The innate immune system plays an important role in shaping the microbiota into configurations that are tolerated and beneficial to the host, thereby playing a crucial role in human health. Innate immunity is based on the fundamental principle that Pattern Recognition Receptors (PRRs) recognise pathogen associated molecular patterns as non-self-entities and trigger intracellular signalling pathways that lead to the induction of numerous cytokines and chemokines that help maintain host resistance to infections. Dysregulation of this interaction has been identified as the core defect that leads to chronic intestinal inflammation allowing certain microbiota to be harmful to host health. This dysbiosis of the microbiome is found associated with numerous chronic diseases. A logical explanation would be that genetic defects in the recognition and response pathways that the host uses to identify these microbial pathogens could lead to altered microbial colonisation or mis-recognition of normal bacteria leading to diseases. The interaction between pattern recognition receptors, microbial traits and human health with respect to the gut are now rapidly resolved and will be the subject of this review.

Systematic review with meta-analysis: breastfeeding and the risk of Crohn's disease and ulcerative colitis

BACKGROUND

Breastfeeding is a modifiable factor that may influence development of inflammatory bowel diseases. However, literature on this has been inconsistent and not accounted for heterogeneity in populations and exposure.

AIM

To conduct a meta-analysis to examine the association between breastfeeding in infancy and risk of Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

A systematic search of Medline/PubMed and Embase was performed for full text, English-language literature through November 2016. Studies were included if they described breastfeeding in infancy in patients with CD or UC, and healthy controls. Data were pooled using a random effects model for analysis.

RESULTS

A total of 35 studies were included in the final analysis, comprising 7536 individuals with CD, 7353 with UC and 330 222 controls. Ever being breastfed was associated with a lower risk of CD (OR 0.71, 95% CI 0.59-0.85) and UC (OR 0.78, 95% CI 0.67-0.91). While this inverse association was observed in all ethnicity groups, the magnitude of protection was significantly greater among Asians (OR 0.31, 95% CI 0.20-0.48) compared to Caucasians (OR 0.78, 95% CI 0.66-0.93; P = .0001) in CD. Breastfeeding duration showed a dose-dependent association, with strongest decrease in risk when breastfed for at least 12 months for CD (OR 0.20, 95% CI 0.08-0.50) and UC (OR 0.21, 95% CI 0.10-0.43) as compared to 3 or 6 months.

CONCLUSION

Breastfeeding in infancy protects against the development of CD and ulcerative colitis.

A review of caffeine use as a risk or protective factor for women's health and pregnancy

PURPOSE OF REVIEW

To provide a narrative synthesis of recently published studies on caffeine use as a risk or protective factor for health outcomes, with a focus on women's health and pregnancy.

RECENT FINDINGS

Based on predominantly observational studies, moderate caffeine intake has been shown to be a protective factor for liver cancer, certain bowel conditions, colorectal cancer, skin cancer, and regular menstrual cycle function. However, heavy consumption is a risk factor for osteoporosis, urinary incontinence, and poorer birth and child developmental outcomes. Residual confounding and issues surrounding retrospective self-reported intake are cited as key limitations in the majority of these studies. Moderate caffeine intake has been associated with lower risk of cardiovascular disease and metabolic syndrome; however, recent genetic epidemiology studies provide no evidence for a causal relationship.

SUMMARY

Greater inclusion of female participants in studies, and analysis of sex differences in the relationship between caffeine intake and certain health conditions, is necessary. The current literature suggests caffeine's role as a risk or protective factor differs across health conditions. Often, there are plausible biological mechanisms for this relationship. However, a continued precautionary stance is recommended until direct causal pathways are established. Review of recently published studies does not suggest that current intake guidelines for adults and for pregnant woman need to be modified.

Coffee and autoimmunity: More than a mere hot beverage!

Coffee is one of the world's most consumed beverage. In the last decades, coffee consumption has attracted a huge body of research due to its impact on health. Recent scientific evidences showed that coffee intake could be associated with decreased mortality from cardiovascular and neurological diseases, diabetes type II, as well as from endometrial and liver cancer, among others. In this review, on the basis of available data in the literature, we aimed to investigate the association between coffee intake and its influence on the immune system and the insurgence of the most relevant autoimmune diseases. While some studies reported conflicting results, general trends have been identified. Coffee consumption seems to increase the risk of developing rheumatoid arthritis (RA) and type 1 diabetes mellitus (T1DM). By contrast, coffee consumption may exert a protective role against multiple sclerosis, primary sclerosing cholangitis, and ulcerative colitis. Concerning other autoimmune diseases such as systemic lupus erythematosus, psoriasis, primary biliary cholangitis and Crohn's disease, no significant association was found. In other studies, coffee consumption was shown to influence disease course and management options. Coffee intake led to a decrease in insulin sensitivity in T1DM, in methotrexate efficacy in RA, and in levothyroxine absorption in Hashimoto's disease. Further, coffee consumption was associated with cross reactivity with gliadin antibodies in celiac patients. Data on certain autoimmune diseases like systemic sclerosis, Sjögren's syndrome, and Behçet's disease, among others, are lacking in the existent literature. As such, further research is warranted.

An Examination of Diet for the Maintenance of Remission in Inflammatory Bowel Disease

Diet has been speculated to be a factor in the pathogenesis of inflammatory bowel disease and may be an important factor in managing disease symptoms. Patients manipulate their diet in attempt to control symptoms, often leading to the adoption of inappropriately restrictive diets, which places them at risk for nutritional complications. Health professionals struggle to provide evidence-based nutrition guidance to patients due to an overall lack of uniformity or clarity amongst research studies. Well-designed diet studies are urgently needed to create an enhanced understanding of the role diet plays in the management of inflammatory bowel disease. The aim of this review is to summarize the current data available on dietary management of inflammatory bowel disease and to demonstrate that dietary modulation may be an important consideration in managing disease. By addressing the relevance of diet in inflammatory bowel disease, health professionals are able to better support patients and collaborate with dietitians to improve nutrition therapy.

Pre-illness diet as risk factor in pediatric inflammatory bowel disease in Saudi Arabia

BACKGROUND/AIM

Inflammatory bowel disease (IBD) is increasing in Saudi Arabia but there's little knowledge about its risk factors. Our aim is to investigate the dietary risk factors of this disease in Saudi children.

PATIENTS AND METHODS

The children investigated for IBD were prospectively enrolled. Those with confirmed IBD were designated cases and the others were controls. The average food frequency intake at least 3 months before onset of illness was obtained by direct interview and recorded on a modified food frequency questionnaire. Fast food, sweet gaseous soft drinks, fruits, and vegetables were selected. Statistical analysis included descriptive statistics, multivariate logistic regression was used, and the odds ratio was calculated to report the statistical significance of the results.

RESULTS

A total of 91 children, 52 IBD (38 CD, 14 UC) and 39 controls were enrolled. Consumption of fast food and sweet gaseous drinks was more frequent in children with IBD than controls, whereas consumption of fruits and vegetables was less frequent in children with IBD. Only less fruits consumption was significantly associated with IBD as the odds of children getting IBD was 2.89 (1.06, 7.87).

CONCLUSIONS

We report statistically significant positive association between less fruits consumption and IBD. Awaiting the results of larger sample size and more quantitative studies, the benefits of frequent fruit consumptions should be part of public health education.

The genetic background of inflammatory bowel disease: from correlation to causality

Recent studies have greatly improved our insight into the genetic background of inflammatory bowel disease (IBD). New high-throughput technologies and large-scale international collaborations have contributed to the identification of 200 independent genetic risk loci for IBD. However, in most of these loci, it is unclear which gene conveys the risk for IBD. More importantly, it is unclear which variant within or near the gene is causal to the disease. Using targeted GWAS, imputation, resequencing of risk loci, and in silico fine-mapping of densely typed loci, several causal variants have been identified in IBD risk genes, and various pathological pathways have been uncovered. Current research in the field of IBD focuses on the effect of these causal variants on gene expression and protein function. However, more elements than only the genome must be taken into account to disentangle the multifactorial pathology of IBD. The genetic risk loci identified to date only explain a small part of genetic variance in disease risk. Currently, large multi-omics studies are incorporating factors ranging from the gut microbiome to the environment. In this review, we present the progress that has been made in IBD genetic research and stress the importance of studying causality to increase our understanding of the pathogenesis of IBD. We highlight important causal genetic variants in the candidate genes NOD2, ATG16L1, IRGM, IL23R, CARD9, RNF186, and PRDM1. We describe their downstream effects on protein function and their direct effects on the gut immune system. Furthermore, we discuss the future role of genetics in unravelling disease mechanisms in IBD. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Selective Induced Altered Coccidians to Immunize and Prevent Enteritis

Microbiomic flora in digestive tract is pivotal to the state of our health and disease. Antibiotics affect GI, control composition of microbiome, and shift equilibrium from health into disease status. Coccidiosis causes gastrointestinal inflammation. Antibiotic additives contaminate animal products and enter food chain, consumed by humans with possible allergic, antibiotic resistance and enigmatic side effects. Purposed study induced nonpathogenic, immunogenic organisms to protect against disease and abolish antibiotics' use in food animals and side effects in man. Diverse species of Coccidia were used as model. Immature organisms were treated with serial purification procedure prior to developmental stages to obtain altered strains. Chicks received oral gavage immunized with serial low doses of normal or altered organisms or sham treatment and were challenged with high infective normal organisms to compare pathogenicity and immunogenicity. Mature induced altered forms of E. tenella and E. necatrix lacked developmental stage of "sporocysts" and contained free sporozoites. In contrast, E. maxima progressed to normal forms or did not mature at all. Animals that received altered forms were considerably protected with higher weight gain and antibody titers against challenge infection compared to those that received normal organisms (p < 0.05). This is the first report to induce selected protective altered organisms for possible preventive measures to minimize antibiotic use in food animals.