Gut hepcidin: a key regulator of inflammation
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Florent Dumont
PROVIDER: E-GEOD-71073 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Hepcidin is demonstrated to be the key iron regulatory hormone, produced by the liver. Here we show an unexpected role of hepcidin as a master initiator of the local and systemic inflammatory response. We found that hepcidin was highly expressed in the colon of two major idiopathic inflammatory bowel diseases : Crohn's disease (CD) and ulcerative colitis (UC). Thanks to the generation of intestinal specific hepcidin KO mice (Hepc{delta}int), we found in a DSS-induced colitis model that hepcidin mediated the induction of key inflammatory cytokines and was protective against intestinal injury. In a model of LPS-induced acute inflammation, intestinal hepcidin expression was increased through a TLR4 dependent pathway andwas required for intestinal neutrophil infiltration and inflammation. Strikingly, intestinal hepcidin was absolutely required for the systemic production of key inflammatory cytokines (IL-6, CXCL1, TNF-alpha ...) as well as for the setting of the hypoferremia of inflammation. In a sepsis model, Hepc{delta}int mice were protected against LPS-induced mortality. Mechanistically, we showed that hepcidin was a direct neutrophil chemoattractant and a proinflammatory molecule in macrophages through a Myd88 dependent pathway. Altogether, we demonstrated that Hepcidin is a key new essential component of the immune system and may be a promising target in many inflammatory diseases.
2019-02-14 | GSE71073 | GEO
Project description:Dysregulated protease activity is often implicated in the initiation of inflammation and immune cell recruitment in gastrointestinal inflammatory diseases. Using N-terminomics/TAILS (terminal amine isotopic labeling of substrates), we compared proteases, along with their substrates and inhibitors, between colonic mucosal biopsies of healthy patients and those with ulcerative colitis (UC). Among the 1,642 N-termini enriched using TAILS, increased endogenous processing of proteins was identified in UC compared to healthy patients. Changes in the reactome pathways for proteins associated with metabolism, adherens junction proteins (E-cadherin, liver-intestinal cadherin, catenin alpha-1 and catenin delta-1) and neutrophil degranulation were identified between the two groups. Increased neutrophil infiltration and distinct proteases observed in ulcerative colitis may result in extensive break down, altered processing or increased remodeling of adherens junctions and other cellular functions. Analysis of the proteolytic preferred cleavage sites indicated that the majority of proteolytic activity and processing comes from host proteases, but that key microbial proteases may also play a role in maintaining homeostasis. Thus, the identification of distinct proteases and processing of their substrates improves the understanding of dysregulated proteolysis in normal intestinal physiology and ulcerative colitis.
2019-09-08 | PXD014479 | Pride
Project description:Neutrophil accumulation in crypt abscesses is a pathological hallmark of ulcerative colitis. Based on recent evidence that mucosal metabolic changes influence disease outcomes, we hypothesized that transmigrating neutrophils influence the transcriptional profile of intestinal epithelia. Microarray studies revealed a cohort of hypoxia-responsive genes regulated by neutrophil-epithelial crosstalk. Real-time O2 sensing indicated that transmigrating neutrophils rapidly deplete microenvironmental O2 sufficient enough to stabilize intestinal epithelial cell hypoxia-inducible factor (HIF). Utilizing HIF reporter mice in a TNBS colitis model, we investigated the relative contribution of neutrophils and the respiratory burst to “inflammatory hypoxia” in vivo. Gp91phox-null mice, which mirror human chronic granulomatous disease, developed accentuated colitis compared to control with exaggerated neutrophil infiltration and diminished inflammatory hypoxia. In conclusion, transcriptional imprinting of host tissue by infiltrating neutrophils modulates the host response to inflammation. Likewise, the respiratory burst contributes fundamentally to localized O2 depletion, resultant microenvironmental hypoxia and effective inflammatory resolution.
2012-10-31 | GSE39681 | GEO
Project description:Neutrophil accumulation in crypt abscesses is a pathological hallmark of ulcerative colitis. Based on recent evidence that mucosal metabolic changes influence disease outcomes, we hypothesized that transmigrating neutrophils influence the transcriptional profile of intestinal epithelia. Microarray studies revealed a cohort of hypoxia-responsive genes regulated by neutrophil-epithelial crosstalk. Real-time O2 sensing indicated that transmigrating neutrophils rapidly deplete microenvironmental O2 sufficient enough to stabilize intestinal epithelial cell hypoxia-inducible factor (HIF). Utilizing HIF reporter mice in a TNBS colitis model, we investigated the relative contribution of neutrophils and the respiratory burst to M-bM-^@M-^\inflammatory hypoxiaM-bM-^@M-^] in vivo. Gp91phox-null mice, which mirror human chronic granulomatous disease, developed accentuated colitis compared to control with exaggerated neutrophil infiltration and diminished inflammatory hypoxia. In conclusion, transcriptional imprinting of host tissue by infiltrating neutrophils modulates the host response to inflammation. Likewise, the respiratory burst contributes fundamentally to localized O2 depletion, resultant microenvironmental hypoxia and effective inflammatory resolution. Two models were employed, direct and indirect. The M-bM-^@M-^\DirectM-bM-^@M-^] migration model entailed establishing a chemotactic gradient (using fMLP) across monolayers of T84 intestinal epithelial cells grown on the underside of permeable supports (3um pore). Neutrophils (PMN) were induced to migrate in the physiologically relevant the physiologically relevant basolateral-to-apical direction. Following migration, T84s were rested in complete media and 2hrs later harvested for RNA isolation. In the Indirect model, PMN were applied to T84s as with the direct model. After migration, conditioned supernatants were collected, cells pelleted and supernatants filtered through 0.2um pore. Conditioned supernatants were transferred to naive T84 monolayers for 2hrs, followed by RNA harvest. Each model was exposed to neutrophils (PMN) or not. All monolayers contained chemotactic peptide fMLP on the apical side. Total of 12 samples, 4 conditions in triplicate: Direct migration without neutrophils (T84 +fMLP -PMN), Direct migration with neutrophils (T84 +fMLP +PMN), Indirect migration without neutrophils (T84 +fMLP -PMN), Indirect migration with neutrophils (T84 +fMLP +PMN)
2012-10-31 | E-GEOD-39681 | biostudies-arrayexpress
Project description:To investigate the detailed molecular mechanisms for the regulatory role of HIF-2α in experimental colitis, microarray gene expression analysis was performed on colon RNA isolated from 6- to 8-week-old Hif-2αF/F, Hif-2αlΔIE mice treated with 3%DSS for 3 days. Background & Aims: Hypoxic inflammation is characterized by decreased oxygen tension in inflammatory foci, and is a notable feature in inflammatory bowel disease (IBD). Hypoxic response is mediated by transcription factors hypoxia-inducible factor (HIF)-1α and HIF-2α, both of which are highly induced in IBD. HIF-1α is a protective factor that limits intestinal barrier dysfunction during inflammation. However, the role of HIF-2α has not been assessed in hypoxic inflammation and IBD. Methods: A hypoxia reporter mouse model was used to test the presence of hypoxia and HIF-2α in dextran sulfate sodium (DSS) and Citrobacter rodentium (C.rod)-induced colitis. The role of HIF-2α in these mouse models of colitis was further assessed in mice with an intestinal epithelium-specific gain- and loss-of-function of HIF-2α. Results: Induction of hypoxia and HIF-2α was confirmed in both murine experimental colitis models and human IBD samples. Disruption of HIF-2α attenuated colonic inflammation whereas stabilization of HIF-2α potentiated inflammation in mouse models of colitis. Interestingly, intestine specific overexpression of HIF-2α but not HIF-1α leads to spontaneous colitis and premature death in mice. Further mechanistic analysis showed that HIF-2α is a driver for pro-inflammatory response and is critical regulator of intestinal epithelial-derived tumor necrosis factor (TNF)-α. Blocking TNF-α completely ameliorated HIF-2α potentiated intestinal inflammation. Conclusions: These data demonstrate that HIF-2α is a critical transcription factor essential in intestinal epithelium elicited inflammatory response. Global gene expression profiling in colon RNAs isolated from 7-week-old Hif-2αF/F (n=6, Shah 007) and Hif-2αΔIE (n=5, Shah 008).
2013-02-28 | E-GEOD-43416 | biostudies-arrayexpress
Project description:Inflammation is a hallmark of multiple disease processes, including inflammatory bowel disease (IBD). The transcription factor NF-kappaB plays a critical role in this response through its effects on pro-inflammatory gene expression. Consequently, homeostatic mechanisms that control NF-kappaB activity have been found to play important roles in controlling inflammatory responses in physiologic and pathologic states. Copper Metabolism Murr1 Domain containing 1 (COMMD1), a regulator of copper excretion and other transport pathways, has been shown to play a role in limiting NF-kappaB activation. However, it remains unclear if this factor plays a necessary role in the control of inflammation or in the pathogenesis of inflammatory disorders in vivo. Using a myeloid-cell specific model of Commd1 deficiency in mice we evaluated the contribution of this factor to inflammatory responses. We found that this gene plays an important role as a negative regulator of the LPS transcriptional response, and deficiency in this factor led to sensitization to in vivo models of sepsis. In addition, we identified single nucleotide variants located near COMMD1 that are associated with decreased expression of this gene in humans. Interestingly, these polymorphisms also show a suggestive association signal with ulcerative colitis risk. Consistent with the possibility that genetic variation in COMMD1 expression may predispose to colitis, we find that myeloid deletion of Commd1 leads to more severe colonic inflammation and cancer progression in experimental colitis models. Altogether, the data support the notion that COMMD1 expression in myeloid cells plays an important anti-inflammatory role in physiologic states and human disease. Bone marrow derived macrophages (BMDM) were isolated from two individual wildtype - and two Commd1 knockout mice. Cells from individual mice were splitted and were treated with LPS for 3h, 24h, or, were left untreated. The corresponding 12 cell samples were subjected to total RNA preparation and subsequently used for Single-Color-based Microarray Analysis (Agilent Technologies).
2014-05-19 | E-GEOD-53368 | biostudies-arrayexpress
Project description:Dunster2014 - WBC Interactions (Model1)
This is a sub-model of a three-step
inflammatory response modelling study. The model includes distinct
populations of white blood cells namely, macrophages and active and
apoptotic neutrophil populations. Neutrophil apoptosis rate is
predicted to be crucial for the qualitative nature of the
system.
This model is described in the article:
The resolution of
inflammation: a mathematical model of neutrophil and macrophage
interactions.
Dunster JL, Byrne HM, King JR.
Bull. Math. Biol. 2014 Aug; 76(8):
1953-1980
Abstract:
There is growing interest in inflammation due to its
involvement in many diverse medical conditions, including
Alzheimer's disease, cancer, arthritis and asthma. The
traditional view that resolution of inflammation is a passive
process is now being superceded by an alternative hypothesis
whereby its resolution is an active, anti-inflammatory process
that can be manipulated therapeutically. This shift in mindset
has stimulated a resurgence of interest in the biological
mechanisms by which inflammation resolves. The
anti-inflammatory processes central to the resolution of
inflammation revolve around macrophages and are closely related
to pro-inflammatory processes mediated by neutrophils and their
ability to damage healthy tissue. We develop a spatially
averaged model of inflammation centring on its resolution,
accounting for populations of neutrophils and macrophages and
incorporating both pro- and anti-inflammatory processes. Our
ordinary differential equation model exhibits two outcomes that
we relate to healthy and unhealthy states. We use bifurcation
analysis to investigate how variation in the system parameters
affects its outcome. We find that therapeutic manipulation of
the rate of macrophage phagocytosis can aid in resolving
inflammation but success is critically dependent on the rate of
neutrophil apoptosis. Indeed our model predicts that an
effective treatment protocol would take a dual approach,
targeting macrophage phagocytosis alongside neutrophil
apoptosis.
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2024-09-02 | BIOMD0000000616 | BioModels
Project description:Hepcidin is demonstrated to be the key iron regulatory hormone, produced by the liver. Here we show an unexpected role of hepcidin as a master initiator of the local and systemic inflammatory response. We demonstrated that Hepcidin is a key new essential component of the immune system and may be a promising target in many inflammatory diseases.
2021-02-13 | GSE95162 | GEO