The microbiome in inflammatory bowel disease and its modulation as a therapeutic manoeuvre

Abstract

Inflammatory bowel disease (IBD) is increasing in incidence in both the developed and the developing world. Genetic, immunological and environmental factors are known to be involved. Genome-wide studies have examined the contribution played by host genetics in the development of IBD and have estimated that genetic factors are responsible for about 25 % of the disease risk. Having an IBD-associated genotype does not always lead to development of the disease phenotype, and hence it seems likely that environmental factors are key to triggering development of the disease in genetically susceptible individuals. The gut microbiota contains more cells than its human host, and mounting evidence attests to the importance of the microbiota in the development of several diseases, including IBD, metabolic syndrome and CVD. The present paper reviews the interplay between the microbiota and the mucosal immune system in health and in IBD; and discusses the evidence base for the use of therapeutic modulation of the microbiota to prevent and treat IBD.

Microbiota from Obese Mice Regulate Hematopoietic Stem Cell Differentiation by Altering the Bone Niche

“…Furthermore, the Gram-positive bacteria appear most relevant in the transfer of the HSC phenotype, since their depletion by VCM also rescues the HSC phenotype observed in HFD mice (Hansen et al, 2012). This finding adds an important role of the microbiota, linking obesity to diseases such as type 2 diabetes (Cani et al, 2008), asthma, and inflammatory bowel diseases (Hart and Hendy, 2014).…”

Vitamin D as a novel therapy in inflammatory bowel disease: new hope or false dawn?

“…Relevant to IBD, there is evidence that vitamin D deficiency may compromise the gastrointestinal mucosal barrier, whereas active vitamin D appears to promotes epithelial integrity through up-regulation of tight junction proteins zonula occcludens-1 and claudin-1 (61,62) . Some reports suggest changes in the gut microbial composition in animal models (63) in response to vitamin D. Despite immense interest in the gut microbiome (64,65) this has yet to be investigated in response to vitamin D therapy in CD. Although some parallels exist, the degree to which the immune effects observed in animal models translate to human IBD is not fully understood.…”

Eurotium cristatum Exhibited Anti-Colitis Effects via Modulating Gut Microbiota-Dependent Tryptophan Metabolism

“…Ulcerative colitis (UC), a kind of inflammatory bowel disease (IBD) that affects the rectum, colonic mucosa, and submucosa, seriously influences the quality of people’s life and leads to colorectal cancer. Currently, UC has become one of the main health problems in the society. − A recent study revealed that the incidence of UC in Europe and North America exceeded 0.3% and influenced millions of people . The specific etiology of UC is still unclear, but numerous research studies have indicated that the incidence of UC is closely linked to genetic factors and gut microbiota. , The structure and diversity of gut microbiota in UC patients are severely disordered, which subsequently impair the production of some gut microbiota-derived functional metabolites and further aggravate UC. , Multiple studies confirmed that gut microbiota-related metabolites including short-chain fatty acids (SCFAs) and tryptophan metabolites such as indole-3-aldehyde (IAld) and indole-3-acetic acid (IAA) could affect the immune balance and improve the expression of tight-junction (TJ) proteins and the maintenance of mucosal integrity. − Especially, IAld and IAA can serve as ligands for the aromatic hydrocarbon receptor (AhR), which is a significant transcription factor exhibiting an important anti-inflammatory function in the intestine by modulating the generation of interleukin (IL)-22.…”