A comprehensive map of microbial biomarkers along the gastrointestinal tract for celiac disease patients

Detoxification Mechanism and the Impact of Transamidation-Modified Gliadin on Celiac-Based Gluten Sensitivity: The Potential of Unlocking Gluten Tolerance in Functional Food

Transamidation of gliadin under reducing conditions has shown promise in mitigating celiac disease-related gluten toxicity. However, comprehensive evaluation in both in vitro and in vivo models is crucial. This study investigated the effects of transamidated gliadin (GM) on celiac toxicity using Caco-2 cell monolayers, bone marrow-derived dendritic cells (BMDCs), and a BALB/c mouse model. In cellular level, GM mitigated intestinal damage compared to unmodified gliadin and stimulated a less pronounced pro-inflammatory response, suggesting a reduced activation of the T-cell-mediated immune system. In vivo, the GM group displayed lower levels of pro-inflammatory factors and less pronounced Th1/Th2 imbalance compared to the unmodified gliadin group. Notably, the GM also improved the balance of the intestinal microbiome. In brief, GM exhibited significantly reduced celiac toxicity in both cellular and animal models that mimics the intestinal environment of celiac disease. These findings suggest that transamidation treatment holds potential as a safer alternative strategy to lower the toxicity of wheat gliadin/wheat flour, potentially paving the way for developing modified gluten-based foods with desirable texture or ingredients as a nutritional enhancer or structure improver, benefiting individuals with specific needs.

Gluten Unraveled: Latest Insights on Terminology, Diagnosis, Pathophysiology, Dietary Strategies, and Intestinal Microbiota Modulations-A Decade in Review

A decade of research on gluten-related disorders (GRDs) is reviewed in this study, with a particular emphasis on celiac disease (CD) and non-celiac gluten sensitivity (NCGS). GRDs are triggered by the ingestion of gluten and gluten-like proteins found in wheat, barley, and rye. These proteins lead to intestinal damage in celiac disease, an autoimmune condition characterized by villous atrophy and a variety of gastrointestinal and extraintestinal symptoms. More enigmatic and less understood, NCGS involves symptoms similar to CD but without the immunological reaction or intestinal damage. Recent years have seen advances in the understanding of GRDs, particularly in connection to how intestinal microbiota influences disease progression and patient outcomes. The gluten-free diet (GFD) is still the standard therapy recommended for GRDs despite significant challenges, as discussed in this article. Precise diagnostic methods, patient education and dietary counseling are critical for improving patients' quality of life. The purpose of this review is to provide a more clear and up-to-date understanding of GRDs, and to help further research on this important topic.

Monitoring coeliac disease in 2024, time to change practice?

PURPOSE OF REVIEW

Persistent villous atrophy is associated with morbidity in coeliac disease and most commonly due to ongoing gluten ingestion. Current methods for assessing gluten exposure and persisting villous atrophy include dietary questionnaires and repeat duodenal biopsy, which have limited accuracy or are invasive. This review discusses adjunctive and/or novel tests that could be used to overcome these challenges.

RECENT FINDINGS

Small bowel capsule endoscopy is well tolerated and helps to evaluate for persisting villous atrophy and importantly, complications associated with coeliac disease. Testing for urinary and/or stool gluten immunogenic peptides may help identify recent gluten exposure, but further studies are still warranted to evaluate the accuracy and applicability of this approach. Measuring spikes in circulating Interleukin-2 following gluten challenge has shown promise for coeliac disease diagnosis, and thus may serve as a useful confirmatory test in those with persisting symptoms but provides no information on mucosal inflammation. No specific gut microbial signature has been identified in coeliac disease; however, studies have shown a reduced microbial diversity in active disease, which with future refinement may prove clinically useful.

SUMMARY

There is no evidence to support alternative methods for assessing persisting villous atrophy in coeliac disease over performing an up-to-date duodenal biopsy. Monitoring for adherence to a gluten-free diet remains clinically challenging and should be a priority for future research.

A review of gluten detoxification in wheat for food applications: approaches, mechanisms, and implications

With the improved knowledge of gluten-related disorders, especially celiac disease (CD), the market of gluten-free food is growing. However, the current gluten-free diet still presents challenges in terms of nutrition, acceptability, and cost due to the absence of gluten. It is important to note that gluten-related allergies or sensitivities have different underlying causes. And individuals with mild non-celiac gluten disorder symptoms may not necessarily require the same gluten-free treatments. Scientists are actively seeking alternative solutions for these consumers. This review delves into the various strategies employed by researchers for detoxifying gluten or modifying its main protein, gliadin, including genetic treatment, transamidation and deamidation, hydrolysis, and microbial treatments. The mechanisms, constraints of these techniques, their current utilization in food items, as well as their implications for gluten-related disorders, are discussed in detail. Although there is still a gap in the application of these methods as alternative solutions in the real market, the summary provided by our review could be beneficial for peers in enriching their basic ideas and developing more applicable solutions for wheat gluten detoxification.

Phage lysins for intestinal microbiome modulation: current challenges and enabling techniques

The importance of the microbiota in the intestinal tract for human health has been increasingly recognized. In this perspective, microbiome modulation, a targeted alteration of the microbial composition, has gained interest. Phage lysins, peptidoglycan-degrading enzymes encoded by bacteriophages, are a promising new class of antibiotics currently under clinical development for treating bacterial infections. Due to their high specificity, lysins are considered microbiome-friendly. This review explores the opportunities and challenges of using lysins as microbiome modulators. First, the high specificity of endolysins, which can be further modulated using protein engineering or targeted delivery methods, is discussed. Next, obstacles and possible solutions to assess the microbiome-friendliness of lysins are considered. Finally, lysin delivery to the intestinal tract is discussed, including possible delivery methods such as particle-based and probiotic vehicles. Mapping the hurdles to developing lysins as microbiome modulators and identifying possible ways to overcome these hurdles can help in their development. In this way, the application of these innovative antimicrobial agents can be expanded, thereby taking full advantage of their characteristics.

Advancing microbiome research with machine learning: key findings from the ML4Microbiome COST action

The rapid development of machine learning (ML) techniques has opened up the data-dense field of microbiome research for novel therapeutic, diagnostic, and prognostic applications targeting a wide range of disorders, which could substantially improve healthcare practices in the era of precision medicine. However, several challenges must be addressed to exploit the benefits of ML in this field fully. In particular, there is a need to establish "gold standard" protocols for conducting ML analysis experiments and improve interactions between microbiome researchers and ML experts. The Machine Learning Techniques in Human Microbiome Studies (ML4Microbiome) COST Action CA18131 is a European network established in 2019 to promote collaboration between discovery-oriented microbiome researchers and data-driven ML experts to optimize and standardize ML approaches for microbiome analysis. This perspective paper presents the key achievements of ML4Microbiome, which include identifying predictive and discriminatory 'omics' features, improving repeatability and comparability, developing automation procedures, and defining priority areas for the novel development of ML methods targeting the microbiome. The insights gained from ML4Microbiome will help to maximize the potential of ML in microbiome research and pave the way for new and improved healthcare practices.

Short chain fatty acids, a possible treatment option for autoimmune diseases

Gut microbiota can interact with the immune system through its metabolites. Short-chain fatty acids (SCFAs), as one of the most abundant metabolites of the resident gut microbiota play an important role in this crosstalk. SCFAs (acetate, propionate, and butyrate) regulate nearly every type of immune cell in the gut's immune cell repertoire regarding their development and function. SCFAs work through several pathways to impose protection towards colonic health and against local or systemic inflammation. Additionally, SCFAs play a role in the regulation of immune or non-immune pathways that can slow the development of autoimmunity either systematically or in situ. The present study aims to summarize the current knowledge on the immunomodulatory roles of SCFAs and the association between the SCFAs and autoimmune disorders such as celiac disease (CD), inflammatory bowel disease (IBD), rheumatoid arthritis (RA), multiple sclerosis (MS), systemic lupus erythematosus (SLE), type 1 diabetes (T1D) and other immune-mediated diseases, uncovering a brand-new therapeutic possibility to prevent or treat autoimmunity.

Interaction between Gut Microbiota and Celiac Disease: From Pathogenesis to Treatment

Celiac disease (CD) is a common systemic disorder that results from an abnormal response of human immunity to gluten intake, affecting the small intestine. In individuals who carry a genetic susceptibility, CD is triggered by environmental factors, including viral infections and dysbiosis of the gut microbiota. The gut microbiome is essential in controlling the immune system, and recent findings indicate that changes in the gut microbiome may contribute to various chronic immune disorders, such as CD through mechanisms that still require further exploration. Some bacteria exhibit epitopes that mimic gliadin and may enhance an immune response in the host. Other bacteria, including Pseudomonas aeruginosa, may work in conjunction with gluten to trigger and escalate intestinal inflammation. The microbiota may also directly influence antigen development through the production of immunogenic or tolerogenic gluten peptides or directly influence intestinal permeability through the release of zonulin. Finally, the gut microbiome can impact intestinal inflammation by generating proinflammatory or anti-inflammatory cytokines and metabolites. It is crucial to consider the impact of genetic factors (specifically, HLA-DQ haplotypes), perinatal elements such as birth mode, type of infant feeding, and antibiotic and infection exposure on the composition of the early intestinal microbiome. According to the available studies, the gut microbiome alterations associated with CD tend to exhibit a decreased presence of beneficial bacteria, including some anti-inflammatory Bifidobacterium species. However, some controversy remains as some reports have found no significant differences between the gut microbiomes of individuals with and without CD. A better understanding of the gut microbiome's role in the development of CD would greatly benefit both prevention and treatment efforts, especially in complicated or treatment-resistant cases. Here, we have attempted to summarize the available evidence on the relationship between the gut microbiota and CD, with a particular focus on potential therapeutic targets.

Malignancies in Patients with Celiac Disease: Diagnostic Challenges and Molecular Advances

Celiac disease (CD) is a multiorgan autoimmune disorder of the chronic intestinal disease group characterized by duodenal inflammation in genetically predisposed individuals, precipitated by gluten ingestion. The pathogenesis of celiac disease is now widely studied, overcoming the limits of the purely autoimmune concept and explaining its hereditability. The genomic profiling of this condition has led to the discovery of numerous genes involved in interleukin signaling and immune-related pathways. The spectrum of disease manifestations is not limited to the gastrointestinal tract, and a significant number of studies have considered the possible association between CD and neoplasms. Patients with CD are found to be at increased risk of developing malignancies, with a particular predisposition of certain types of intestinal cancer, lymphomas, and oropharyngeal cancers. This can be partially explained by common cancer hallmarks present in these patients. The study of gut microbiota, microRNAs, and DNA methylation is evolving to find the any possible missing links between CD and cancer incidence in these patients. However, the literature is extremely mixed and, therefore, our understanding of the biological interplay between CD and cancer remains limited, with significant implications in terms of clinical management and screening protocols. In this review article, we seek to provide a comprehensive overview of the genomics, epigenomics, and transcriptomics data on CD and its relation to the most frequent types of neoplasms that may occur in these patients.

The emerging role of the small intestinal microbiota in human health and disease

The human gut microbiota continues to demonstrate its importance in human health and disease, largely owing to the countless number of studies investigating the fecal microbiota. Underrepresented in these studies, however, is the role played by microbial communities found in the small intestine, which, given the essential function of the small intestine in nutrient absorption, host metabolism, and immunity, is likely highly relevant. This review provides an overview of the methods used to study the microbiota composition and dynamics along different sections of the small intestine. Furthermore, it explores the role of the microbiota in facilitating the small intestine in its physiological functions and discusses how disruption of the microbial equilibrium can influence disease development. The evidence suggests that the small intestinal microbiota is an important regulator of human health and its characterization has the potential to greatly advance gut microbiome research and the development of novel disease diagnostics and therapeutics.