Diet-Induced Host-Microbe Interactions: Personalized Diet Strategies for Improving Inflammatory Bowel Disease

Lab-on-chip technologies for exploring the gut-immune axis in metabolic disease

The continued rise in metabolic diseases such as obesity and type 2 diabetes mellitus poses a global health burden, necessitating further research into factors implicated in the onset and progression of these diseases. Recently, the gut-immune axis, with diet as a main regulator, has been identified as a possible role player in their development. Translation of conventional 2D in vitro and animal models is however limited, while human studies are expensive and preclude individual mechanisms from being investigated. Lab-on-chip technology therefore offers an attractive new avenue to study gut-immune interactions. This review provides an overview of the influence of diet on gut-immune interactions in metabolic diseases and a critical analysis of the current state of lab-on-chip technology to study this axis. While there has been progress in the development of "immuno-competent" intestinal lab-on-chip models, with studies showing the ability of the technology to provide mechanical cues, support longer-term co-culture of microbiota and maintain in vivo-like oxygen gradients, platforms which combine all three and include intestinal and immune cells are still lacking. Further, immune cell types and inclusion of microenvironment conditions which enable in vivo-like immune cell dynamics as well as host-microbiome interactions are limited. Future model development should focus on combining these conditions to create an environment capable of hosting more complex microbiota and immune cells to allow further study into the effects of diet and related metabolites on the gut-immune ecosystem and their role in the prevention and development of metabolic diseases in humans.

Roles of Short-Chain Fatty Acids in Inflammatory Bowel Disease

The gut microbiome is a diverse bacterial community in the human gastrointestinal tract that plays important roles in a variety of biological processes. Short-chain fatty acids (SCFA) are produced through fermentation of dietary fiber. Certain microbes in the gut are responsible for producing SCFAs such as acetate, propionate and butyrate. An imbalance in gut microbiome diversity can lead to metabolic disorders and inflammation-related diseases. Changes in SCFA levels and associated microbiota were observed in IBD, suggesting an association between SCFAs and disease. The gut microbiota and SCFAs affect reactive oxygen species (ROS) associated with IBD. Gut microbes and SCFAs are closely related to IBD, and it is important to study them further.

Unraveling the Impact of Gut and Oral Microbiome on Gut Health in Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) is a complex disorder characterized by chronic inflammation of the gastrointestinal tract (GIT). IBD mainly includes two distinct diseases, namely Crohn's disease and ulcerative colitis. To date, the precise etiology of these conditions is not fully elucidated. Recent research has shed light on the significant role of the oral and gut microbiome in the development and progression of IBD and its collective influence on gut health. This review aims to investigate the connection between the oral and gut microbiome in the context of IBD, exploring the intricate interplay between these microbial communities and their impact on overall gut health. Recent advances in microbiome research have revealed a compelling link between the oral and gut microbiome, highlighting their pivotal role in maintaining overall health. The oral cavity and GIT are two interconnected ecosystems that harbor complex microbial communities implicated in IBD pathogenesis in several ways. Reduction in diversity and abundance of beneficial bacterial species with the colonization of opportunistic pathogens can induce gut inflammation. Some of these pathogens can arise from oral origin, especially in patients with oral diseases such as periodontitis. It is essential to discern the mechanisms of microbial transmission, the impact of oral health on the gut microbiome, and the potential role of dysbiosis in disease development. By elucidating this relationship, we can enhance our understanding of IBD pathogenesis and identify potential therapeutic avenues for managing the disease. Furthermore, innovative strategies for modulating the oral and gut microbiome can promote health and prevent disease occurrence and progression.

Role of an Exclusion Diet (Reduced Disaccharides, Saturated Fats, Emulsifiers, Red and Ultraprocessed Meats) in Maintaining the Remission of Chronic Inflammatory Bowel Diseases in Adults

Background and Objectives: Inflammatory bowel diseases are a main focus in current research, with diet being an emerging therapeutic line due to its links in both onset and progression. A Western-style diet high in processed foods, food additives, red meat, and animal fat has been linked to a higher risk of developing IBD. The aim of this study was to establish an association between an anti-inflammatory exclusion diet and maintenance of remission in IBD. Also, we assessed the efficacy and safety of this diet compared to a non-dietary group and the possible therapeutic effect of this diet in the maintenance of IBD remission. Materials and Methods: A total of 160 patients with IBD were screened for inclusion, but 21 did not met the inclusion criteria. Thus, 139 patients were assigned to either an exclusion diet or a regular diet according to their choice. Results: Clinical remission after six months was maintained in the exclusion diet arm (100%). In the control arm, four patients had clinically active disease (one patient with UC and three with CD), and 90 patients maintained the clinical remission state (95.7%) (p-value = 0.157). Regarding biochemical markers, ESR at baseline was higher in the exclusion diet arm: 29 (5-62) versus in the control arm 16 (4-48) (p-value = 0.019), but six months after, the groups were similar (p-value = 0.440). Conclusions: Patients who followed an exclusion diet maintained clinical remission more frequently. However, the threshold for statistical significance was not achieved. There was also a trend of improvement in inflammation tests in the intervention group.