The Role of Gluten in Celiac Disease and Type 1 Diabetes. Nutrients. 2015;7:7143-7162. [PMID: 26343710 PMCID: PMC4586524 DOI: 10.3390/nu7095329]

A novel gluten knowledge base of potential biomedical and health-related interactions extracted from the literature: using machine learning and graph analysis methodologies to reconstruct the bibliome

BACKGROUND

In return for their nutritional properties and broad availability, cereal crops have been associated with different alimentary disorders and symptoms, with the majority of the responsibility being attributed to gluten. Therefore, the research of gluten-related literature data continues to be produced at ever-growing rates, driven in part by the recent exploratory studies that link gluten to non-traditional diseases and the popularity of gluten-free diets, making it increasingly difficult to access and analyse practical and structured information. In this sense, the accelerated discovery of novel advances in diagnosis and treatment, as well as exploratory studies, produce a favourable scenario for disinformation and misinformation.

OBJECTIVES

Aligned with, the European Union strategy "Delivering on EU Food Safety and Nutrition in 2050" which emphasizes the inextricable links between imbalanced diets, the increased exposure to unreliable sources of information and misleading information, and the increased dependency on reliable sources of information; this paper presents GlutKNOIS, a public and interactive literature-based database that reconstructs and represents the experimental biomedical knowledge extracted from the gluten-related literature. The developed platform includes different external database knowledge, bibliometrics statistics and social media discussion to propose a novel and enhanced way to search, visualise and analyse potential biomedical and health-related interactions in relation to the gluten domain.

METHODS

For this purpose, the presented study applies a semi-supervised curation workflow that combines natural language processing techniques, machine learning algorithms, ontology-based normalization and integration approaches, named entity recognition methods, and graph knowledge reconstruction methodologies to process, classify, represent and analyse the experimental findings contained in the literature, which is also complemented by data from the social discussion.

RESULTS

and Conclusions: In this sense, 5,814 documents were manually annotated and 7,424 were fully automatically processed to reconstruct the first online gluten-related knowledge database of evidenced health-related interactions that produce health or metabolic changes based on the literature. In addition, the automatic processing of the literature combined with the knowledge representation methodologies proposed has the potential to assist in the revision and analysis of years of gluten research. The reconstructed knowledge base is public and accessible at https://sing-group.org/glutknois/.

Lessons and Gaps in the Prediction and Prevention of Type 1 Diabetes

Type 1 diabetes (T1D) is a serious chronic autoimmune condition. Even though the root cause of T1D development has yet to be determined, enough is known about the natural history of T1D pathogenesis to allow study of interventions that may delay or even prevent the onset of hyperglycemia and clinical T1D. Primary prevention aims to prevent the onset of beta cell autoimmunity in asymptomatic people at high genetic risk for T1D. Secondary prevention strategies aim to preserve functional beta cells once autoimmunity is present, and tertiary prevention aims to initiate and extend partial remission of beta cell destruction after the clinical onset of T1D. The approval of teplizumab in the United States to delay the onset of clinical T1D marks an impressive milestone in diabetes care. This treatment opens the door to a paradigm shift in T1D care. People with T1D risk need to be identified early by measuring T1D related islet autoantibodies. Identifying people with T1D before they have symptoms will facilitate better understanding of pre-symptomatic T1D progression and T1D prevention strategies that may be effective.

DMPPred: a tool for identification of antigenic regions responsible for inducing type 1 diabetes mellitus

There are a number of antigens that induce autoimmune response against β-cells, leading to type 1 diabetes mellitus (T1DM). Recently, several antigen-specific immunotherapies have been developed to treat T1DM. Thus, identification of T1DM associated peptides with antigenic regions or epitopes is important for peptide based-therapeutics (e.g. immunotherapeutic). In this study, for the first time, an attempt has been made to develop a method for predicting, designing, and scanning of T1DM associated peptides with high precision. We analysed 815 T1DM associated peptides and observed that these peptides are not associated with a specific class of HLA alleles. Thus, HLA binder prediction methods are not suitable for predicting T1DM associated peptides. First, we developed a similarity/alignment based method using Basic Local Alignment Search Tool and achieved a high probability of correct hits with poor coverage. Second, we developed an alignment-free method using machine learning techniques and got a maximum AUROC of 0.89 using dipeptide composition. Finally, we developed a hybrid method that combines the strength of both alignment free and alignment-based methods and achieves maximum area under the receiver operating characteristic of 0.95 with Matthew's correlation coefficient of 0.81 on an independent dataset. We developed a web server 'DMPPred' and stand-alone server for predicting, designing and scanning T1DM associated peptides (https://webs.iiitd.edu.in/raghava/dmppred/).

Gluten-Free Diet in Co-Existent Celiac Disease and Type 1 Diabetes Mellitus: Is It Detrimental or Beneficial to Glycemic Control, Vascular Complications, and Quality of Life?

Celiac disease (CeD) is associated with type 1 diabetes mellitus (T1DM), and both have the same genetic background. Most patients with T1DM who develop CeD are either asymptomatic or have mild CeD-related gastrointestinal symptoms. Therefore, children affected by T1DM should undergo screening for asymptomatic CeD. The aim of this review is to highlight the influence of a gluten-free diet (GFD) on glycemic control, growth rate, microvascular complications, and quality of life in patients with T1DM and CeD. PubMed, Google Scholar, Web of Science, and Cochrane Central databases were searched. Reports reviewed were those published from 1969 to 2022 that focused on the interplay of T1DM and CeD and examined the effect of diet on glycemic control, growth rate, and quality of life. The most challenging aspect for a child with T1DM and CeD is that most GFD foods have a high glycemic index, while low glycemic index foods are recommended for T1DM. Interestingly, dietary therapy for CeD could improve the elevated HbA1c levels. Avoiding gluten added to a diabetic dietary regimen in T1DM patients might impose practical limitations and lead to important restrictions in the lifestyle of a young patient. Consequently, non-adherence to GFD in patients with T1DM and CeD is common. GFD in patients with T1DM and CeD seems to lower the incidence of micro- and macrovascular complications, but this requires further investigation. It seems that adherence to GFD in young patients with T1DM and CeD leads to regular growth and a stable body mass index without any negative effect on HbA1c or insulin requirements. Furthermore, the lipid profile and quality of life seem to have improved with the introduction of GFD.

The gut microbiota and celiac disease: Pathophysiology, current perspective and new therapeutic approaches

Celiac disease (CD) as a chronic gluten-sensitive intestinal condition, mainly affects genetically susceptible hosts. The primary determinants of CD have been identified as environmental and genetic variables. The development of CD is significantly influenced by environmental factors, including the gut microbiome. Therefore, gut microbiome re-programming-based therapies using probiotics, prebiotics, postbiotics, gluten-free diet, and fecal microbiota transplantation have shown promising results in the modification of the gut microbiome. Due to the importance and paucity of information regarding the CD pathophysiology, in this review, we have covered the association between CD development and gut microbiota, the effects of infectious agents, particularly the recent Covid-19 infection in CD patients, and the efficacy of potential therapeutic approaches in the CD have been discussed. Hence, scientific literature indicates that the diverse biological functions of the gut microbiota against immunomodulatory responses have made microbiome-based therapy an alternative therapeutic paradigm to ameliorate the symptoms of CD and quality of life. However, the exact potential of microbiota-based techniques that aims to quantitatively and qualitatively alter the gut microbiota to be used in the treatment and ameliorate the symptoms of CD will be determined with further research in the future.

An Evaluation of Nutritional Status and Problems with Dietary Compliance in Polish Patients with Celiac Disease

Celiac disease (CD, enteropathy) is a genetic autoimmune disease (abnormal immune response that attacks healthy tissues) associated with gluten intolerance. The aim of this study was to evaluate and monitor the nutritional status of CD patients, explore the problems associated with diet planning and dietary adherence among children and adults, and assess the impact of these factors on the persistence of CD symptoms. This study was carried out as part of the project entitled “A gluten-free diet without obstacles—eating well and healthy” (POWR 03.01.00-00-T153/18), conducted in Lublin Voivodeship. The study involved 87 persons, including 23 children younger than 18. At the beginning of the study and after nine months, all adult participants (older than 18) were subjected to a body composition analysis with the SECA mBCA 515 analyzer. During the project, the participants attended three consultations with a dietician. During each visit, the subjects’ body weight, nutritional status and diets were evaluated; their diets were modified, and problems relating to dietary adherence were resolved. The initial body composition analysis revealed a risk of sarcopenic obesity in 30% of adult participants, in particular in women (p = 0.003) older than 45 (p = 0.001). The risk of being underweight was diagnosed in 25% of the subjects, in particular, in women younger than 35 (p = 0.0023) and in participants who had been affected by short stature and underweight in childhood, i.e., before CD diagnosis (p = 0.0024). The analysis demonstrated that patients with gastrointestinal symptoms (abdominal pain, diarrhea, vomiting) of CD were significantly more likely to avoid even accidental exposure to gluten and were more likely to strictly follow GFD recommendations (1.97; 95CI:1.56–2.12, p = 0.0001) and safety guidelines when preparing meals at home (1.76; 95CI: 1.34–192, p = 0.0023). Parents, in particular, parents of toddlers and preschoolers who are at significantly higher risk of CD, adhered strictly to dietary guidelines and did not allow for any exceptions when preparing meals (1.88; 95CI: 1.53–2.09, p = 0.001). Persons at risk of malnutrition were also far less likely to deliberately choose gluten-containing foods (0.74; 95CI: 0.53–0.91, p = 0.021), in particular, patients with Marsh type 3a and 3b classification (p = 0.01) and persons whose intestinal histology scores did not fully improve after switching to a GFD. An assessment of the effectiveness of diet therapy based on the phase angle revealed that dietary recommendations had a positive impact on patients who had been recently diagnosed with CD. In all age groups, the main problem was accidental exposure to gluten, in particular in foods that were not labeled with the crossed grain symbol. A comparative analysis of CDAT questionnaires revealed that dietary advice on eating out significantly improved adherence to a GFD and reduced the frequency of unintentional gluten exposure in all age groups.

Liver Involvement in Children during the Diagnosis of Celiac Disease: A Single-Center Experience from Turkey

BACKGROUND: Liver abnormalities in Celiac disease (CD) are common. The aim of this study was to investigate the children with CD who were followed up in our clinic presenting with elevated aminotransferase levels. METHODS: In this study, the data of 419 pediatric patients with CD were retrospectively analyzed, and those with elevated aminotransferase levels during the diagnosis of CD were assessed. RESULTS: Elevation of aminotransferase levels was found in 66 (15.7%) patients among the 419 patients during the diagnosis of CD. The mean age of these patients was 7.33±3.96 years. Liver enzymes were mildly elevated in 63 (95.4%) patients. However, half of the patients with elevated liver enzymes had a 1.25-fold increase in aminotransferase levels. Patients with hypertransaminasemia had higher weight loss and lower folic acid values compared with patients with normal liver enzymes. Patients' liver tests were reverted to normal, except for two patients with chronic liver disease, after 9.27±3.16 months of administering a gluten-free diet. CONCLUSION: Patients with liver involvement should be investigated for CD. Especially, mildly elevation of aminotransferase levels should be taken into account by pediatricians for Celiac hepatitis.

The Impact of Intestinal Microorganisms and Their Metabolites on Type 1 Diabetes Mellitus

BACKGROUND

Type 1 diabetes mellitus (T1DM) is an autoimmune disease with a complex etiology comprising numerous genetic and environmental factors; however, many of the mechanisms underlying disease development remain unclear. Nevertheless, a critical role has recently been assigned to intestinal microorganisms in T1DM disease pathogenesis. In particular, a decrease in intestinal microbial diversity, increase in intestinal permeability, and the translocation of intestinal bacteria to the pancreas have been reported in patients and animal models with T1DM. Moreover, intestinal microbial metabolites differ between healthy individuals and patients with T1DM. Specifically, short-chain fatty acid (SCFA) production, which contributes to intestinal barrier integrity and immune response regulation, is significantly reduced in patients with T1DM. Considering this correlation between intestinal microorganisms and T1DM, many studies have investigated the potential of intestinal microbiota in preventive and therapeutic strategies for T1DM.

OBJECTIVE

The aim of this review is to provide further support for the notion that intestinal microbiota contributes to the regulation of T1DM occurrence and development. In particular, this article reviews the involvement of the intestinal microbiota and the associated metabolites in T1DM pathogenesis, as well as recent studies on the involvement of the intestinal microbiota in T1DM prevention and treatment.

CONCLUSION

Intestinal microbes and their metabolites contribute to T1DM occurrence and development and may become a potential target for novel therapeutics.

Celiac Disease as a Cause of Anemia and Brittle Diabetes in Type 1 Diabetes Mellitus

Untreated celiac disease (CD) leads to an increased risk for hypoglycemia and diabetic complications. However, the diagnosis of CD can be challenging and some extra-gastrointestinal tract manifestations could be a presenting symptom. We report a case of a 29-year-old Indian male with brittle T1DM whose underlying CD was discovered from a work-up for anemia. After an introduction of a gluten-free diet, he gained 5 kgs in two months, was responsive to oral iron supplement, and had stable glycemic control with much less hypoglycemia. Even though this disease is rare in Asian populations, the diagnosis of celiac disease should always be kept in mind when people with T1DM present with unexplained microcytic anemia and/or unexplained hypoglycemia.

Optimal Frequency to Screen Celiac Disease amongst Patients with Type 1 Diabetes Mellitus: A Multicenter Study

AIMS

Celiac disease (CD) is frequent amongst patients with type 1 diabetes mellitus (T1DM). Since there is a disagreement on the optimal interval and frequency to perform screening tests for CD among diabetic patients, this study aimed to evaluate these issues amongst patients with T1DM.

METHODS

This retrospective cohort study was conducted in seven referral diabetic centers in different cities of Iran from January 2020 to January 2021. Data belonging to 106 patients who were affected by both T1DM and CD was collected. The time interval between CD diagnosis and diabetes (IBCD), the age of diabetes onset, and any associated diseases, symptoms, and family history of T1DM and CD were recorded and analyzed.

RESULTS

Results show that 45% of the patients with CD were diagnosed during the first year of diabetes onset; furthermore, 18% and 16% of the patients with CD were diagnosed in the second or third year after being diagnosed with diabetes. In addition, another 18% of patients with CD were diagnosed during the fourth till the eighth year after diabetes onset. Moreover, there was a negative relationship between the age of T1DM diagnosis and IBCD. Most participants were asymptomatic at the time of CD diagnosis.

CONCLUSIONS

Screening tests to detect CD amongst patients with T1DM should continue for at least eight years after the initial T1DM diagnosis, especially those affected at a younger age.

A review on the effect of prolyl isomerization on immune response aberration and hypersensitivity reactions: A unifying hypothesis

Little is known about the causes and mechanisms of ectopic immune responses, including different types of hypersensitivity, superantigens, and cytokine storms. Two of the most questionable phenomena observed in immunology are why the intensity and extent of immune responses to different antigens are different, and why some self-antigens are attacked as foreign. The secondary structure of the peptides involved in the immune system, such as the epitope-paratope interfaces plays a pivotal role in the resulting immune responses. Prolyl cis/trans isomerization plays a fundamental role in the form of the secondary structure and the folding of proteins. This review covers some of the emerging evidence indicating the impact of prolyl isomerization on protein conformation, aberration of immune responses, and the development of hypersensitivity reactions.

Co-Silencing of Tissue Transglutaminase-2 and Interleukin-15 Genes in a Celiac Disease Mimetic Mouse Model Using a Nanoparticle-in-Microsphere Oral System

Celiac disease is a chronic inflammatory condition characterized by activation of the immune system in response to deamidation of gluten peptides brought about by tissue transglutaminase-2 (TG2). Overexpression of interleukin-15 (IL-15) in the intestinal epithelium and the lamina propria leads to the dysregulation of the immune system, leading to epithelial damage. The goal of this study was to develop an RNA interference therapeutic strategy for celiac disease using a combination of TG2 and IL-15 gene silencing in the inflamed intestine. TG2 and IL-15 silencing siRNA sequences, along with scrambled control, were encapsulated in a nanoparticle-in-microsphere oral system (NiMOS) and administered in a poly(I:C) mouse model of celiac disease. Single TG2 and IL-15 siRNA therapy and the combination showed effective gene silencing in vivo. Additionally, it was found that IL-15 gene silencing alone and combination in the NiMOS significantly reduced other proinflammatory cytokines. The tissue histopathology data also confirmed a reduction in immune cell infiltration and restoration of the mucosal architecture and barrier function in the intestine upon treatment. Overall, the results of this study show evidence that celiac disease can be potentially treated with an oral microsphere formulation using a combination of TG2 and IL-15 RNA interference therapeutic strategies.

An updated overview on celiac disease: from immuno-pathogenesis and immuno-genetics to therapeutic implications

INTRODUCTION

Celiac disease (CD) is an autoimmune enteropathy triggered by ingestion of gluten. While presenting many similarities with other autoimmune diseases, celiac disease is unique in that the external trigger, gluten, and the genetic background necessary for disease development (HLA DQ2/DQ8) are well described. The prevalence of celiac disease is dramatically increasing over the years and new epidemiologic data show changes regarding age of onset and symptoms. A better understanding of CD-pathogenesis is fundamental to highlight the reasons of this rise of celiac diagnoses.

AREAS COVERED

In this review we describe CD-pathogenesis by dissecting all the components necessary to lose tolerance to gluten (ingestion of gluten, genetic predisposition, loss of barrier function and immune response). Additionally, we also highlight the role that microbiome plays in celiac disease as well as new proposed therapies and experimental tools.

EXPERT OPINION

Prevalence of autoimmune diseases is increasing around the world. As a result, modern society is strongly impacted by a social and economic burden. Given the unique characteristics of celiac disease, a better understanding of its pathogenesis and the factors that contribute to it may shed light on other autoimmune diseases for which external trigger and genetic background are not known.

Dietary SCFAs Immunotherapy: Reshaping the Gut Microbiota in Diabetes

Diet-microbiota related inflammatory conditions such as obesity, autoimmune type 1 diabetes (T1D), type 2 diabetes (T2D), cardiovascular disease (CVD) and gut infections have become a stigma in Western societies and developing nations. This book chapter examines the most relevant pre-clinical and clinical studies about diet-gut microbiota approaches as an alternative therapy for diabetes. We also discuss what we and others have extensively investigated- the power of dietary short-chain fatty acids (SCFAs) technology that naturally targets the gut microbiota as an alternative method to prevent and treat diabetes and its related complications.

Influence of Ultra-Processed Foods Consumption on Redox Status and Inflammatory Signaling in Young Celiac Patients

The current study was designed to assess the influence of consumption of ultra-processed (UPF) on oxidative/antioxidant balance and evoked inflammatory signaling in young patients with celiac disease (CD). The study included 85 children. The celiac group (n = 53) included children with CD with a long (>18 months, n = 17) or recent (<18 months, n = 36) adherence to a gluten-free diet (GFD). The control group (n = 32) included healthy children with a significantly lower consumption of UPF compared to the CD group, both expressed as kcal/day (p = 0.043) and as percentage of daily energy intake (p = 0.023). Among children with CD, the group with the lowest consumption of UPF (below the 50% of daily energy intake) had a greater Mediterranean diet (MD) adherence and higher moderate physical activity levels. In addition, CD children with the lowest consumption of UPF had healthier redox (lower soluble superoxide dismutase-1 and 15-F2t-isoprostanes) and inflammatory profiles (lower macrophage inflammatory protein-1α) compared to the group with the highest consumption of UPF (all, p < 0.05) regardless of the time on a GFD. These findings highlight the importance of a correct monitoring of the GFD. An unbalanced GFD with high consumption of UPF and an unhealthy pattern with less physical activity and worse adherence to MD results in a worse inflammatory profile, which could act as a parallel pathway that could have important consequences on the pathophysiology of the disease.

Frequency of alleles associated with celiac disease in patients with autoimmune thyroid disease

ABSTRACT Objective To determine the frequency of Human leukocyte antigen alleles and to verify the association of the presence of these alleles with symptoms and other diseases related to celiac disease in patients with autoimmune thyroid diseases. Methods A questionnaire on the symptoms and diseases associated with celiac disease was applied. Genomic deoxyribonucleic acid was extracted by collecting cells from the oral mucosa. The alleles (DQA1*0501; DQB1*0201; DRB1*04) were identified by means of the polymerase chain reaction. Results A total of 110 patients with autoimmune thyroid diseases participated in this study. It was observed that 66.4% of the individuals carried at least one of the alleles assessed and that 58.2% of the individuals were positive for at least one of the DQ2 alleles (DQA1*0501; DQB1*0201) and out of these 18.2% were positive for both DQ2 alleles (DQA1*0501; DQB1*0201). With regard to DQ8 (DRB1*04), 21.8% of the studied population was positive for this allele and 3.6% was positive for both DQ2 (DQA1*0501; DQB1*0201) and DQ8 (DRB1*04). A significant association was found between the presence of the DRB1*04 allele and gastrointestinal symptoms (p=0.02). A significant association of the DRB1*04 allele with type 1 diabetes mellitus (p=0.02) was observed. Conclusion The genetic profiles most commonly associated with celiac disease, such as DQ2 (DQA1*0501; DQB1*0201) and DQ8 (DRB1*04) were around 20.0% prevalent in the studied population. These are risk haplotypes for celiac disease especially when symptoms and diseases related to celiac disease are present. Therefore, it is important to screen patients to investigate a potential diagnosis for celiac disease.

Gluten Free Diet for the Management of Non Celiac Diseases: The Two Sides of the Coin

A lifelong adherence to a gluten-free (GF) diet is currently the only treatment for Celiac disease (CD), an autoimmune disorder that arises after gluten ingestion in individuals who are genetically predisposed. The gluten intake exerts toxic effects through several pathways involving gut barrier integrity, intestinal microbiota composition and immune system stimulation. However, despite the great benefit of GF diet for CD patients, its use has been debated. Indeed, individuals who adopt this diet regime may be at risk of nutrient deficiencies. Emerging evidence supports a beneficial effect of a GF diet also for other pathological conditions, including gluten-related disorders (GRD) often associated to CD, such as Non celiac gluten sensitivity (NCGS) and Dermatitis Herpetiforme (DH) as well as Irritable bowel syndrome (IBS) and Diabetes. This suggests a pathogenic role of gluten in these conditions. Despite the growing popularity of GF diet among consumers, to date, there are limited evidences supporting its use for the management of non-celiac diseases. Therefore, in this review, we discuss whether the GF diet could really improve the general quality of life of patients with GRD and non-GRD conditions, keeping in mind its sensorial limitations and nutritional inadequacies. In addition, we discuss the current motivations, leading to the use of a GF diet, despite the inferior quality of GF products respect to those containing gluten.

Zonulin as a potential putative biomarker of risk for shared type 1 diabetes and celiac disease autoimmunity

The incidence of type 1 diabetes (T1D) is increasing annually, in addition to other childhood-onset autoimmune diseases. This review is inspired by recent strides in research defining the pathophysiology of autoimmunity in celiac disease, a disease that has significant genetic overlap with T1D. Population genetic studies have demonstrated an increased proportion of newly diagnosed young children with T1D also have a higher genetic risk of celiac disease, suggesting that shared environmental risk factors are driving the incidence of both diseases. The small intestine barrier forms a tightly regulated interface of the immune system with the outside world and largely controls the mucosal immune response to non-self-antigens, dictating the balance between tolerance and immune response. Zonulin is the only known physiological modulator of the intercellular tight junctions, important in antigen trafficking, and therefore, is a key player in regulation of the mucosal immune response. While usually tightly controlled, when the zonulin pathway is dysregulated by changes in microbiome composition and function, antigen trafficking control is lost, leading to loss of mucosal tolerance in genetically susceptible individuals. The tenant of this hypothesis is that loss of tolerance would not occur if the zonulin-dependent intestinal barrier function is restored, thereby preventing the influence of environmental triggers in individuals genetically susceptible to autoimmunity. This review outlines the current research and a structured hypothesis on how a dysregulated small intestinal epithelial barrier, a "leaky gut," may be important in the pathogenesis of autoimmunity in certain individuals at risk of both T1D and celiac disease.

Pharmacokinetics and Biodistribution Analysis of Small Interference RNA for Silencing Tissue Transglutaminase-2 in Celiac Disease After Oral Administration in Mice Using Gelatin-Based Multicompartmental Delivery Systems

Background: RNA interference (RNAi) therapy has tremendous potential in treating diseases that are characterized by overexpression of genes. However, the biggest challenge to utilize the therapy is to engineer delivery systems that can efficiently transport small interfering RNA (siRNA) to appropriate target sites. Our objective in this study was to develop and evaluate multi-compartmental systems for the oral delivery of siRNA that targets the overexpressed TG2 gene (TG2-siRNA) in the small intestine for the treatment of celiac disease (CD). Materials and Methods: Two types of multicompartmental systems were developed and evaluated: (1) a solid-in-solid multicompartmental system featuring "nanoparticle in microsphere oral system (NiMOS)" where type B gelatin nanoparticles containing TG2-siRNA (TG2-NiMOS) were encapsulated within poly(ɛ-caprolactone) (PCL) based microspheres, and (2) a solid-in-liquid multicompartmental system, "Nanoparticle-in-Emulsion (NiE)" consisting of type-B gelatin nanoparticles containing TG2-siRNA encapsulated within safflower oil containing water-in-oil-in-water (W/O/W) multiple emulsion (TG2-NiE). Results: Evaluation of the biodistribution and pharmacokinetics (PK) after a single oral dose of siRNA containing multicompartmental systems to C57BL/6 mice showed that TG2-siRNA was delivered to the small intestine (duodenum, jejunum and ileum), and colon with minimal systemic exposure via both TG2-NiE and TG2-NiMOS systems. TG2-siRNA exposure (AUC_0-t) in the duodenum, jejunum, ileum and colon was 56.4-, 34.3-, 85.5- and 35.5-fold greater for the TG2-NiMOS formulation, relative to the TG2-NiE formulation. Conclusion: The results of this study suggest that TG2-NiMOS formulation was more superior than TG2-NiE formulation in facilitating intestinal delivery of siRNA via the oral route of administration and can be potentially used in the treatment of CD.

Insights into the reason of Human-Residential Bifidobacteria (HRB) being the natural inhabitants of the human gut and their potential health-promoting benefits

Members of Bifidobacterium are among the first microbes to colonise the human gut, and certain species are recognised as the natural resident of human gut microbiota. Their presence in the human gut has been associated with health-promoting benefits and reduced abundance of this genus is linked with several diseases. Bifidobacterial species are assumed to have coevolved with their hosts and include members that are naturally present in the human gut, thus recognised as Human-Residential Bifidobacteria (HRB). The physiological functions of these bacteria and the reasons why they occur in and how they adapt to the human gut are of immense significance. In this review, we provide an overview of the biology of bifidobacteria as members of the human gut microbiota and address factors that contribute to the preponderance of HRB in the human gut. We highlight some of the important genetic attributes and core physiological traits of these bacteria that may explain their adaptive advantages, ecological fitness, and competitiveness in the human gut. This review will help to widen our understanding of one of the most important human commensal bacteria and shed light on the practical consideration for selecting bifidobacterial strains as human probiotics.

Genetic and Environmental Contributors for Celiac Disease

PURPOSE OF REVIEW

Celiac disease (CD) is an autoimmune enteropathy triggered by gluten. The purpose of this review is to examine the major genetic and environmental factors that contribute to CD pathogenesis.

RECENT FINDINGS

We reviewed the current state of knowledge on the genetic and environmental components that play a role in CD onset. A genome-wide association study (GWAS) analysis has highlighted several genes other than HLA involved in CD. Recent studies have shown that HLA haplotype influences the microbiome composition in infants and that dysbiosis in the intestinal microflora, in turn, contributes to loss of tolerance to gluten. Recently, observational studies have discussed the hypothesis stating that breast-feeding had a protective role against CD onset. CD etiology is influenced by genetic and environmental factors. A better understanding of these components would deepen our knowledge on the mechanisms that lead to loss of tolerance and could help in developing a more "personalized medicine."

Design, synthesis and biological activity evaluation of a new class of 2,4-thiazolidinedione compounds as insulin enhancers

Diabetes mellitus (DM) is a global disease with a high incidence of type 2 diabetes. Current studies have shown that insulin enhancers play an important role in the treatment of type 2 diabetes and have great importance in the improvement of type 2 diabetes. In this research, Rosiglitazone was taken as the lead compound, and the structure was modified by using the bioisostere principle, and a new class of 2,4-thiazolanedione compound was designed and synthesised. The novel series of compounds were studied for their biological activities in vitro and in vivo. In vitro tests, the biological activities showed that the target compounds have good selective activation of peroxisome-proliferator-activated receptor γ (PPARγ), such as the compounds 6a, 6e, 6f, 6g and 6i, especially the compound 6e to PPARγ was EC₅₀ = 0.03 ± 0.01 μmol/L in vitro. Then, in vivo biological activities’ test results showed that the tendency of increasing in blood sugar had an obvious inhibiting effect, and had a significant insulin hypoglycaemic effect of enhancing and extending the exogenous. In addition, the results of cytotoxicity tests and acute toxicity tests (LD₅₀) showed that these compounds belong to the low toxicity compounds.

Oxidative stress, DNA stability and evoked inflammatory signaling in young celiac patients consuming a gluten-free diet

PURPOSE

Celiac disease (CD) is a multifactorial, autoimmune, gluten-sensitive inflammatory disorder of the small intestine. Taking into account the pathogenesis of CD, a strict gluten-free diet (GFD) is the only treatment able to restore epithelium integrity and eliminate complications. The current study was designed to assess whether the use of a GFD is sufficient for maintaining a correct oxidative/antioxidant balance and ameliorating the evoked inflammatory signaling in young patients with CD.

METHODS

The study covered 80 children, aged between 7 and 18 years, attending the Gastroenterology Service of the Gastroenterology, Hepatology and Child Nutrition Service from the Virgen de las Nieves Hospital in Granada. Children with CD diagnosed were included in the celiac group who followed a strict GFD for 2 years (n = 40) and the control group (n = 40) included healthy children, with negative serological screening. Soluble superoxide dismutase 1 and 2, total antioxidant status, 8-hydroxy-2'-deoxyguanosine, cortisol, melatonin and inflammatory parameters in plasma, 15-F2t-isoprostanes in urine, and DNA breaks in peripheral blood lymphocytes were analysed.

RESULTS

No differences were found in oxidative stress between CD patients and controls; however, IFN-γ, IL-1α, IP-10 and TNF-β were higher in the CD patients. VEGF was also higher than in the control group.

CONCLUSION

The GFD in the CD patients is enough to reduce the oxidative stress; however, in the case of the inflammatory signaling, the initial exposure to gluten prior to stablish the GFD is strong enough to induce an inflammatory state which is maintained (even when consuming the GFD); meanwhile the increase in VEGF recorded in the CD group could be a compensatory mechanism to restore the damaged mucosa and duodenal villous atrophy, due to its role in endothelial activation and generation of new functional and stable vascular networks.

Human gut derived-organoids provide model to study gluten response and effects of microbiota-derived molecules in celiac disease

Celiac disease (CD) is an immune-mediated disorder triggered by gluten exposure. The contribution of the adaptive immune response to CD pathogenesis has been extensively studied, but the absence of valid experimental models has hampered our understanding of the early steps leading to loss of gluten tolerance. Using intestinal organoids developed from duodenal biopsies from both non-celiac (NC) and celiac (CD) patients, we explored the contribution of gut epithelium to CD pathogenesis and the role of microbiota-derived molecules in modulating the epithelium’s response to gluten. When compared to NC, RNA sequencing of CD organoids revealed significantly altered expression of genes associated with gut barrier, innate immune response, and stem cell functions. Monolayers derived from CD organoids exposed to gliadin showed increased intestinal permeability and enhanced secretion of pro-inflammatory cytokines compared to NC controls. Microbiota-derived bioproducts butyrate, lactate, and polysaccharide A improved barrier function and reduced gliadin-induced cytokine secretion. We concluded that: (1) patient-derived organoids faithfully express established and newly identified molecular signatures characteristic of CD. (2) microbiota-derived bioproducts can be used to modulate the epithelial response to gluten. Finally, we validated the use of patient-derived organoids monolayers as a novel tool for the study of CD.

Gluten Intake and Risk of Islet Autoimmunity and Progression to Type 1 Diabetes in Children at Increased Risk of the Disease: The Diabetes Autoimmunity Study in the Young (DAISY)

OBJECTIVE

To study the association of gluten intake with development of islet autoimmunity and progression to type 1 diabetes.

RESEARCH DESIGN AND METHODS

The Diabetes Autoimmunity Study in the Young (DAISY) follows children with an increased risk of type 1 diabetes. Blood samples were collected at 9, 15, and 24 months of age, and annually thereafter. Islet autoimmunity was defined by the appearance of at least one autoantibody against insulin, IA2, GAD, or ZnT8 (zinc transporter 8) in at least two consecutive blood samples. Using food frequency questionnaires, we estimated the gluten intake (in grams per day) annually from 1 year of age. Cox regression modeling early gluten intake, and joint modeling of the cumulative gluten intake during follow-up, were used to estimate hazard ratios adjusted for confounders (aHR).

RESULTS

By August 2017, 1,916 subjects were included (median age at end of follow-up 13.5 years), islet autoimmunity had developed in 178 participants, and 56 of these progressed to type 1 diabetes. We found no association between islet autoimmunity and gluten intake at 1-2 years of age or during follow-up (aHR per 4 g/day increase in gluten intake 1.00, 95% CI 0.85-1.17 and 1.01, 0.99-1.02, respectively). We found similar null results for progression from islet autoimmunity to type 1 diabetes. Introduction of gluten at <4 months of age was associated with an increased risk of progressing from islet autoimmunity to type 1 diabetes compared with introduction at 4-5.9 months (aHR 8.69, 95% CI 1.69-44.8).

CONCLUSIONS

Our findings indicate no strong rationale to reduce the amount of gluten in high-risk children to prevent development of type 1 diabetes.

Growth and glycemic control in children with type 1 diabetes and asymptomatic celiac disease treated with a gluten -free diet for 1 year

To compare growth and glycemic control in children with type 1 diabetes and silent celiac disease treated with a gluten-free diet for 1 year with those of similar age and gender with type 1 diabetes but without celiac disease, 16 type 1 diabetes patients with silent celiac disease were enrolled and each celiac disease-positive case was matched for age, sex, and duration of diabetes with two type 1 diabetes controls with negative serologic markers of celiac disease. All 16 children with positive celiac disease serology had histologic features consistent with celiac disease despite the absence of symptoms. The mean growth and metabolic control values were similar between children with type 1 diabetes and celiac disease and those with type 1 diabetes but without celiac disease. This study seems to suggest that the early diagnosis of celiac disease and initiation of a gluten-free diet may prevent further deterioration in the nutritional status of children with type 1 diabetes and celiac disease and may reduce the prospect of celiac disease complications without any impact on type 1 diabetes control.

Possible Prevention of Diabetes with a Gluten-Free Diet

Gluten seems a potentially important determinant in type 1 diabetes (T1D) and type 2 diabetes (T2D). Intake of gluten, a major component of wheat, rye, and barley, affects the microbiota and increases the intestinal permeability. Moreover, studies have demonstrated that gluten peptides, after crossing the intestinal barrier, lead to a more inflammatory milieu. Gluten peptides enter the pancreas where they affect the morphology and might induce beta-cell stress by enhancing glucose- and palmitate-stimulated insulin secretion. Interestingly, animal studies and a human study have demonstrated that a gluten-free (GF) diet during pregnancy reduces the risk of T1D. Evidence regarding the role of a GF diet in T2D is less clear. Some studies have linked intake of a GF diet to reduced obesity and T2D and suggested a role in reducing leptin- and insulin-resistance and increasing beta-cell volume. The current knowledge indicates that gluten, among many environmental factors, may be an aetiopathogenic factors for development of T1D and T2D. However, human intervention trials are needed to confirm this and the proposed mechanisms.

Human Microbe-Disease Association Prediction With Graph Regularized Non-Negative Matrix Factorization

A microbe is a microscopic organism which may exists in its single-celled form or in a colony of cells. In recent years, accumulating researchers have been engaged in the field of uncovering microbe-disease associations since microbes are found to be closely related to the prevention, diagnosis, and treatment of many complex human diseases. As an effective supplement to the traditional experiment, more and more computational models based on various algorithms have been proposed for microbe-disease association prediction to improve efficiency and cost savings. In this work, we developed a novel predictive model of Graph Regularized Non-negative Matrix Factorization for Human Microbe-Disease Association prediction (GRNMFHMDA). Initially, microbe similarity and disease similarity were constructed on the basis of the symptom-based disease similarity and Gaussian interaction profile kernel similarity for microbes and diseases. Subsequently, it is worth noting that we utilized a preprocessing step in which unknown microbe-disease pairs were assigned associated likelihood scores to avoid the possible negative impact on the prediction performance. Finally, we implemented a graph regularized non-negative matrix factorization framework to identify potential associations for all diseases simultaneously. To assess the performance of our model, cross validations including global leave-one-out cross validation (LOOCV) and local LOOCV were implemented. The AUCs of 0.8715 (global LOOCV) and 0.7898 (local LOOCV) proved the reliable performance of our computational model. In addition, we carried out two types of case studies on three different human diseases to further analyze the prediction performance of GRNMFHMDA, in which most of the top 10 predicted disease-related microbes were verified by database HMDAD or experimental literatures.

HLA-class II haplotypes and Autism Spectrum Disorders

Infections and autoimmunity are associated with autism spectrum disorders (ASD), with both strongly influenced by the genetic regulation of the human leukocyte antigen (HLA) system. The relationship between ASD and the HLA genetic diversity requires further investigation. Using a case control design, the distribution of HLA class II-DRB1 and DQB1 alleles, genotypes and haplotypes were investigated in ASD patients, versus healthy controls (HC). ASD patients meeting DSM-IV TR criteria and HC (474 and 350 respectively) were genotyped at medium resolution using a Luminex-based SSO technology. Comparisons of genotypes, allele frequencies associated with a haplotype analysis were performed. Results indicate: (i) the HLA-DRB1 *11-DQB1*07 haplotype was more prevalent in ASD patients, versus HC (Pc = 0.001), partially replicating previous data and possibly linking to gastro-intestinal (GI)-related pro-inflammatory processes, given that this haplotype associates with pediatric celiac disorders; (ii) the HLA-DRB1 *17-DQB1*02 haplotype was higher in HC, versus ASD patients (Pc = 0.002), indicating that this is a protective haplotype. Using the Autism Diagnostic Interview to assess clinical dimensions, higher scores on social (Pc = 0.006) and non-verbal functioning (Pc = 0.004) associated with the DRB1 *11 DQB1*07 haplotype. Our results support HLA involvement in ASD, with possible relevance to GI and gut-brain axis dysregulation.

Degradation of food-derived opioid peptides by bifidobacteria

Some food-derived opioid peptides have been reported to cause diseases, such as gastrointestinal inflammation, celiac disease, and mental disorders. Bifidobacterium is a major member of the dominant human gut microbiota, particularly in the gut of infants. In this study, we evaluated the potential of Bifidobacterium in the degradation of food-derived opioid peptides. All strains tested showed some level of dipeptidyl peptidase activity, which is thought to be involved in the degradation of food-derived opioid peptides. However, this activity was higher in bifidobacterial strains that are commonly found in the intestines of human infants, such as Bifidobacterium longum subsp. longum, B. longum subsp. infantis, Bifidobacterium breve and Bifidobacterium bifidum, than in those of other species, such as Bifidobacterium animalis and Bifidobacterium pseudolongum. In addition, some B. longum subsp. infantis and B. bifidum strains showed degradative activity in food-derived opioid peptides such as human and bovine milk-derived casomorphin-7 and wheat gluten-derived gliadorphin-7. A further screening of B. bifidum strains revealed some bifidobacterial strains that could degrade all three peptides. Our results revealed the potential of Bifidobacterium species in the degradation of food-derived opioid peptides, particularly for species commonly found in the intestine of infants. Selected strains of B. longum subsp. infantis and B. bifidum with high degradative capabilities can be used as probiotic microorganisms to eliminate food-derived opioid peptides and contribute to host health.

Gut Microbiota and Type 1 Diabetes

Recently, the onset of type 1 diabetes (T1D) has increased rapidly and became a major public health concern worldwide. Various factors are associated with the development of T1D, such as diet, genome, and intestinal microbiota. The gastrointestinal (GI) tract harbors a complex and dynamic population of microorganisms, the gut microbiota, which exert a marked influence on the host homeostasis and metabolic diseases. Recent evidence shows that altered gut bacterial composition (dysbiosis) is highly associated with the pathogenesis of insulin dysfunction and T1D and, thus, targeting gut microbiota may serve as a therapeutic potential for T1D patients. In this study, we updated the effect of gut microbiota on T1D and potential mechanisms were discussed.

Expression level of risk genes of MHC class II is a susceptibility factor for autoimmunity: New insights

To date, the study of the impact of major hystocompatibility complex on autoimmunity has been prevalently focused on structural diversity of MHC molecules in binding and presentation of (auto)antigens to cognate T cells. Recently, a number of experimental evidences suggested new points of view to investigate the complex relationships between MHC gene expression and the individual predisposition to autoimmune diseases. Irrespective of the nature of the antigen, a threshold of MHC-peptide complexes needs to be reached, as well as a threshold of T cell receptors engaged is required, for the activation and proliferation of autoantigen-reactive T cells. Moreover, it is well known that increased expression of MHC class II molecules may alter the T cell receptor repertoire during thymic development, and affect the survival and expansion of mature T cells. Many evidences confirmed that the level of both transcriptional and post-transcriptional regulation are involved in the modulation of the expression of MHC class II genes and that both contribute to the predisposition to autoimmune diseases. Here, we aim to focus some of these regulative aspects to better clarify the role of MHC class II genes in predisposition and development of autoimmunity.

Soluble Syndecan-1: A Novel Biomarker of Small Bowel Mucosal Damage in Children with Celiac Disease

BACKGROUND

Syndecan-1 (SDC1) is essential for maintaining normal epithelial barrier. Shedding of SDC1 ectodomain, reflected by serum soluble syndecan-1 (SSDC1) levels, is regulated by inflammation. Increased intestinal permeability plays a central role in celiac disease (CD). The association between SSDC1 levels and mucosal damage in CD has not been evaluated.

AIMS

To evaluate serum SSDC1 levels in children with CD and to determine its relationship with histological grading classified by modified Marsh criteria.

METHODS

This is a cross-sectional, pilot study, in which serum SSDC1 was analyzed by ELISA in a cohort of 49 untreated children with CD and 15 children with nonspecific abdominal pain (AP). CD was diagnosed based on positive celiac serology and small intestinal biopsy. SSDC1 levels at the time of biopsy were correlated with Marsh grading. Controls were defined by AP, negative celiac serology, normal upper endoscopy, and small intestinal biopsies.

RESULTS

SSDC1 levels were significantly higher in CD patients compared to AP controls (116.2 ± 161 vs. 41.3 ± 17.5 ng/ml, respectively, p < 0.01). SSDC1 levels were significantly higher in patients with Marsh 3c lesion compared to AP controls (170.6 ± 201 vs. 41.3 ± 17.5 ng/ml, respectively, p < 0.05). SSDC1 concentrations displayed a significant correlation with mucosal damage defined by Marsh (r = 0.39, p < 0.05).

CONCLUSION

This is the first study demonstrating elevated levels of serum SSDC1 in children with CD. Our results suggest that SSDC1 is a potentially novel marker of intestinal mucosal damage in patients with CD. Its applicability as a surrogate biomarker in CD remains to be determined.

Physiopathology and Management of Gluten-Induced Celiac Disease

Proline- and glutamine-rich gluten proteins are one of the major constituents of cereal dietary proteins, which are largely resistant to complete cleavage by the human gastrointestinal (GI) digestive enzymes. Partial digestion of gluten generates approximately 35 amino acids (aa) immunomodulatory peptides which activate T-cell-mediated immune system, followed by immunological inflammation of mucosa leading to the onset of celiac disease (CD). CD is an autoimmune disease associated with HLA-DQ2/DQ8 polymorphism and dysbiosis of gut microbiota. CD is either diagnosed using duodenal mucosal biopsis or serological testing for transglutaminase 2 (TG2) specific antibodies (IgA and IgG). Current therapy for CD management is gluten-free diet, while other therapies like glutenase, probiotics, immunomodulation, jamming of HLA-DQ2, inhibition of TG2, and gluten tolerance aided by gluten tolerizing vaccines are being developed.

Endocrine manifestations in celiac disease

Celiac disease (CD) is an autoimmune small intestinal mucosal disorder that often presents with diarrhea, malabsorption and weight loss. Often, one or more associated endocrine disorders may be associated with CD. For this review, methods involved an extensive review of published English-language materials. In children and adolescents, prospective studies have demonstrated a significant relationship to insulin-dependent or type 1 diabetes, whereas in adults, autoimmune forms of thyroid disease, particularly hypothyroidism, may commonly co-exist. In some with CD, multiple glandular endocrinopathies may also occur and complicate the initial presentation of the intestinal disease. In others presenting with an apparent isolated endocrine disorder, serological screening for underlying subclinical CD may prove to be positive, particularly if type 1 diabetes, autoimmune thyroid or other autoimmune endocrine diseases, such as Addison’s disease are first detected. A number of reports have also recorded hypoparathyroidism or hypopituitarism or ovarian failure in CD and these may be improved with a strict gluten-free diet.

Interaction between wheat alpha-amylase/trypsin bi-functional inhibitor and mammalian digestive enzymes: Kinetic, equilibrium and structural characterization of binding

Alpha-amylase/trypsin bi-functional inhibitors (ATIs) are non-gluten protein components of wheat and other cereals that can hypersensitise the human gastrointestinal tract, eventually causing enteropathies in predisposed individuals. These inhibitory proteins can act both directly by targeting specific pro-inflammatory receptors, and indirectly by impairing the activity of digestive enzymes, the latter event causing the accumulation of undigested peptides with potential immunogenic properties. Herein, according to a concerted approach based on in vitro and in silico methods we characterized kinetics, equilibrium parameters and modes of binding of the complexes formed between wheat ATI and two representative mammalian digestive enzymes, namely trypsin and alpha-amylase. Interestingly, we demonstrated ATI to target both enzymes with independent binding sites and with moderately high affinity.