PubMed · 13526426
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
G SALZER. 1957. Regional Enteritis.. https://pubmed.ncbi.nlm.nih.gov/13526426/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Exclusive enteral nutrition (EEN) is a first-line therapy for pediatric Crohn's disease (CD), but protective mechanisms remain unknown. We established a prospective pediatric cohort to characterize the function of fecal microbiota and metabolite changes of treatment-naive CD patients in response to EEN (German Clinical Trials DRKS00013306). Integrated multi-omics analysis identified network clusters from individually variable microbiome profiles, with Lachnospiraceae and medium-chain fatty acids as protective features. Bioorthogonal non-canonical amino acid tagging selectively identified bacterial species in response to medium-chain fatty acids. Metagenomic analysis identified high strain-level dynamics in response to EEN. Functional changes in diet-exposed fecal microbiota were further validated using gut chemostat cultures and microbiota transfer into germ-free Il10-deficient mice. Dietary model conditions induced individual patient-specific strain signatures to prevent or cause inflammatory bowel disease (IBD)-like inflammation in gnotobiotic mice. Hence, we provide evidence that EEN therapy operates through explicit functional changes of temporally and individually variable microbiome profiles.
AIM: Eph receptor tyrosine kinases and their membrane bound receptor-like ligands, the ephrins, represent a bi-directional cell-cell contact signaling system that directs epithelial movements in development. The meaning of this system in the adult human gut is unknown. We investigated the Eph/ephrin mRNA expression in the intestinal epithelium of healthy controls and patients with inflammatory bowel disease (IBD). METHODS: mRNA expression profiles of all Eph/ephrin family members in normal small intestine and colon were established by real-time RT-PCR. In addition, differential expression in IBD was investigated by cDNA array technology, and validated by both real-time RT-PCR and immunohistochemistry. Potential effects of enhanced EphB/ephrin-B signaling were analyzed in an in vitro IEC-6 cell scratch wound model. RESULTS: Human adult intestinal mucosa exhibits a complex pattern of Eph receptors and ephrins. Beside the known prominent co-expression of EphA2 and ephrinA1, we found abundantly co-expressed EphB2 and ephrin-B1/2. Interestingly, cDNA array data, validated by real-time PCR and immunohistochemistry, showed upregulation of ephrin-B2 in both perilesional and lesional intestinal epithelial cells of IBD patients, suggesting a role in epithelial homeostasis. Stimulation of ephrin-B signaling in ephrin-B1/2 expressing rat IEC-6-cells with recombinant EphB1-Fc resulted in a significant dose-dependent acceleration of wound closure. Furthermore, fluorescence microscopy showed that EphB1-Fc induced coordinated migration of wound edge cells is associated with enhanced formation of lamellipodial protrusions into the wound, increased actin stress fiber assembly and production of laminin at the wound edge. CONCLUSION: EphB/ephrin-B signaling might represent a novel protective mechanism that promotes intestinal epithelial wound healing, with potential impact on epithelial restitution in IBD.
Susceptibility to the development of Crohn's disease involves a combination of genetic and environmental factors. The association of Crohn's disease with westernization has implicated lifestyle factors in pathogenesis. While diet is a likely candidate, evidence for specific changes in dietary habits and/or intake has been lacking. A new hypothesis is proposed, by which excessive delivery of highly fermentable but poorly absorbed short-chain carbohydrates and polyols (designated FODMAPs--Fermentable Oligo-, Di- and Mono-saccharides And Polyols) to the distal small intestinal and colonic lumen is a dietary factor underlying susceptibility to Crohn's disease. The subsequent rapid fermentation of FODMAPs in the distal small and proximal large intestine induces conditions in the bowel that lead to increased intestinal permeability, a predisposing factor to the development of Crohn's disease. Evidence supporting this hypothesis includes the increasing intake of FODMAPs in western societies, the association of increased intake of sugars in the development of Crohn's disease, and the previously documented effects of the ingestion of excessive FODMAPs on the bowel. This hypothesis provides potential for the design of preventive strategies and raises concern about current enthusiasm for putative health-promoting effects of FODMAPs. One of the greatest challenges in defining the pathogenesis of Crohn's disease is to identify predisposing environmental factors. Such an achievement might lead to the development of preventive strategies for, and the definition of, possible target for changing the natural history of this serious disease. The present paper describes a new hypothesis for one such environmental factor.