RESUMEN
Crohn's disease (CD) is a complex chronic inflammatory disorder with both gastrointestinal and extra-intestinal manifestations associated immune dysregulation. Analyzing 202,359 cells from 170 specimens across 83 patients, we identify a distinct epithelial cell type in both terminal ileum and ascending colon (hereon as 'LND') with high expression of LCN2, NOS2, and DUOX2 and genes related to antimicrobial response and immunoregulation. LND cells, confirmed by in-situ RNA and protein imaging, are rare in non-IBD controls but expand in active CD, and actively interact with immune cells and specifically express IBD/CD susceptibility genes, suggesting a possible function in CD immunopathogenesis. Furthermore, we discover early and late LND subpopulations with different origins and developmental potential. A higher ratio of late-to-early LND cells correlates with better response to anti-TNF treatment. Our findings thus suggest a potential pathogenic role for LND cells in both Crohn's ileitis and colitis.
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Colon , Enfermedad de Crohn , Oxidasas Duales , Células Epiteliales , Íleon , Lipocalina 2 , Enfermedad de Crohn/patología , Enfermedad de Crohn/genética , Enfermedad de Crohn/inmunología , Humanos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Colon/patología , Íleon/patología , Lipocalina 2/metabolismo , Lipocalina 2/genética , Oxidasas Duales/genética , Oxidasas Duales/metabolismo , Masculino , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Femenino , Adulto , Factor de Necrosis Tumoral alfa/metabolismo , Mucosa Intestinal/patología , Mucosa Intestinal/metabolismo , Persona de Mediana EdadRESUMEN
Hypusine is an amino acid synthesized by the enzyme deoxyhypusine synthase (DHPS). It is critical for the activity of eukaryotic translation initiation factor 5A (EIF5A). We reported that hypusination i) in macrophages supports the innate response towards pathogenic bacteria and ii) in epithelial cells maintains intestinal homeostasis. Herein, we investigated the effect of myeloid hypusination on the outcome of colitis and colitis-associated cancer. We found that patients with Crohn's disease exhibit increased levels of DHPS and EIF5AHyp in cells infiltrating the colon lamina propria. However, the specific deletion of Dhps in myeloid cells had no impact on clinical, histological, or inflammatory parameters in mice treated with dextran sulfate sodium (DSS). Further, tumorigenesis and level of dysplasia were not affected by myeloid deletion of Dhps in the azoxymethane-DSS model. The composition of the fecal and the mucosa-associated microbiome was similar in animals lacking or not DHPS in myeloid cells. Thus, hypusination in myeloid cells does not regulate colitis associated with epithelial injury and colitis-associated cancer. Enhancement of the DHPS/hypusine pathway in patients with inflammatory bowel disease could have therapeutic impact through epithelial effects, but modulation of hypusination in myeloid cells will be unlikely to affect the disease.
RESUMEN
The intestinal immune response is crucial in maintaining a healthy gut, but the enhanced migration of macrophages in response to pathogens is a major contributor to disease pathogenesis. Integrins are ubiquitously expressed cellular receptors that are highly involved in immune cell adhesion to endothelial cells while in the circulation and help facilitate extravasation into tissues. Here we show that specific deletion of the Tln1 gene encoding the protein talin-1, an integrin-activating scaffold protein, from cells of the myeloid lineage using the Lyz2-cre driver mouse reduces epithelial damage, attenuates colitis, downregulates the expression of macrophage markers, decreases the number of differentiated colonic mucosal macrophages, and diminishes the presence of CD68-positive cells in the colonic mucosa of mice infected with the enteric pathogen Citrobacter rodentium. Bone marrow-derived macrophages lacking expression of Tln1 did not exhibit a cell-autonomous phenotype; there was no impaired proinflammatory gene expression, nitric oxide production, phagocytic ability, or surface expression of CD11b, CD86, or major histocompatibility complex II in response to C. rodentium. Thus, we demonstrate that talin-1 plays a role in the manifestation of infectious colitis by increasing mucosal macrophages, with an effect that is independent of macrophage activation.
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Colitis , Infecciones por Enterobacteriaceae , Animales , Ratones , Citrobacter rodentium , Colitis/genética , Colitis/prevención & control , Colon/patología , Células Endoteliales/metabolismo , Infecciones por Enterobacteriaceae/metabolismo , Inflamación/patología , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Talina/genética , Talina/metabolismoRESUMEN
BACKGROUND & AIMS: The amino acid hypusine, synthesized from the polyamine spermidine by the enzyme deoxyhypusine synthase (DHPS), is essential for the activity of eukaryotic translation initiation factor 5A (EIF5A). The role of hypusinated EIF5A (EIF5AHyp) remains unknown in intestinal homeostasis. Our aim was to investigate EIF5AHyp in the gut epithelium in inflammation and carcinogenesis. METHODS: We used human colon tissue messenger RNA samples and publicly available transcriptomic datasets, tissue microarrays, and patient-derived colon organoids. Mice with intestinal epithelial-specific deletion of Dhps were investigated at baseline and in models of colitis and colon carcinogenesis. RESULTS: We found that patients with ulcerative colitis and Crohn's disease exhibit reduced colon levels of DHPS messenger RNA and DHPS protein and reduced levels of EIF5AHyp. Similarly, colonic organoids from colitis patients also show down-regulated DHPS expression. Mice with intestinal epithelial-specific deletion of Dhps develop spontaneous colon hyperplasia, epithelial proliferation, crypt distortion, and inflammation. Furthermore, these mice are highly susceptible to experimental colitis and show exacerbated colon tumorigenesis when treated with a carcinogen. Transcriptomic and proteomic analysis on colonic epithelial cells demonstrated that loss of hypusination induces multiple pathways related to cancer and immune response. Moreover, we found that hypusination enhances translation of numerous enzymes involved in aldehyde detoxification, including glutathione S-transferases and aldehyde dehydrogenases. Accordingly, hypusination-deficient mice exhibit increased levels of aldehyde adducts in the colon, and their treatment with a scavenger of electrophiles reduces colitis. CONCLUSIONS: Hypusination in intestinal epithelial cells has a key role in the prevention of colitis and colorectal cancer, and enhancement of this pathway via supplementation of spermidine could have a therapeutic impact.
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Colitis , Espermidina , Humanos , Animales , Ratones , Espermidina/farmacología , Espermidina/metabolismo , Proteómica , Factores de Iniciación de Péptidos/genética , Factores de Iniciación de Péptidos/metabolismo , Carcinogénesis/genética , Colitis/inducido químicamente , Colitis/genética , Colitis/prevención & control , Homeostasis , InflamaciónRESUMEN
Colorectal cancer (CRC) is a major health problem worldwide. Dicarbonyl electrophiles, such as isolevuglandins (isoLGs), are generated from lipid peroxidation and form covalent adducts with amine-containing macromolecules. We have shown high levels of adducts of isoLGs in colonic epithelial cells of patients with CRC. We thus investigated the role of these reactive aldehydes in colorectal cancer development. We found that 2-hydroxybenzylamine (2-HOBA), a natural compound derived from buckwheat seeds that acts as a potent scavenger of electrophiles, is bioavailable in the colon of mice after supplementation in the drinking water and does not affect the colonic microbiome. 2-HOBA reduced the level of isoLG adducts to lysine as well as tumorigenesis in models of colitis-associated carcinogenesis and of sporadic CRC driven by specific deletion of the adenomatous polyposis coli gene in colonic epithelial cells. In parallel, we found that oncogenic NRF2 activation and signaling were decreased in the colon of 2-HOBA-treated mice. Additionally, the growth of xenografted human HCT116 CRC cells in nude mice was significantly attenuated by 2-HOBA supplementation. In conclusion, 2-HOBA represents a promising natural compound for the prevention and treatment of CRC.
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Colitis , Neoplasias Colorrectales , Humanos , Ratones , Animales , Aldehídos , Ratones Desnudos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/prevención & controlRESUMEN
Pathogenic enteric Escherichia coli present a significant burden to global health. Food-borne enteropathogenic E. coli (EPEC) and Shiga toxin-producing E. coli (STEC) utilize attaching and effacing (A/E) lesions and actin-dense pedestal formation to colonize the gastrointestinal tract. Talin-1 is a large structural protein that links the actin cytoskeleton to the extracellular matrix though direct influence on integrins. Here we show that mice lacking talin-1 in intestinal epithelial cells (Tln1Δepi) have heightened susceptibility to colonic disease caused by the A/E murine pathogen Citrobacter rodentium. Tln1Δepi mice exhibit decreased survival, and increased colonization, colon weight, and histologic colitis compared to littermate Tln1fl/fl controls. These findings were associated with decreased actin polymerization and increased infiltration of innate myeloperoxidase-expressing immune cells, confirmed as neutrophils by flow cytometry, but more bacterial dissemination deep into colonic crypts. Further evaluation of the immune population recruited to the mucosa in response to C. rodentium revealed that loss of Tln1 in colonic epithelial cells (CECs) results in impaired recruitment and activation of T cells. C. rodentium infection-induced colonic mucosal hyperplasia was exacerbated in Tln1Δepi mice compared to littermate controls. We demonstrate that this is associated with decreased CEC apoptosis and crowding of proliferating cells in the base of the glands. Taken together, talin-1 expression by CECs is important in the regulation of both epithelial renewal and the inflammatory T cell response in the setting of colitis caused by C. rodentium, suggesting that this protein functions in CECs to limit, rather than contribute to the pathogenesis of this enteric infection.
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Colitis , Infecciones por Enterobacteriaceae , Microbioma Gastrointestinal , Animales , Ratones , Citrobacter rodentium , Talina/genética , Escherichia coli/metabolismo , Actinas/metabolismo , Linfocitos T/metabolismo , Colitis/microbiología , Colon/microbiología , Mucosa Intestinal/metabolismo , Infecciones por Enterobacteriaceae/microbiología , Ratones Endogámicos C57BLRESUMEN
The cytokine interleukin-23 (IL-23) is involved in the pathogenesis of inflammatory and autoimmune conditions including inflammatory bowel disease (IBD). IL23R is enriched in intestinal Tregs, yet whether IL-23 modulates intestinal Tregs remains unknown. Here, investigating IL-23R signaling in Tregs specifically, we show that colonic Tregs highly express Il23r compared with Tregs from other compartments and their frequency is reduced upon IL-23 administration and impairs Treg suppressive function. Similarly, colonic Treg frequency is increased in mice lacking Il23r specifically in Tregs and exhibits a competitive advantage over IL-23R-sufficient Tregs during inflammation. Finally, IL-23 antagonizes liver X receptor pathway, cellular cholesterol transporter Abca1, and increases Treg apoptosis. Our results show that IL-23R signaling regulates intestinal Tregs by increasing cell turnover, antagonizing suppression, and decreasing cholesterol efflux. These results suggest that IL-23 negatively regulates Tregs in the intestine with potential implications for promoting chronic inflammation in patients with IBD.
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Colitis , Enfermedades Inflamatorias del Intestino , Animales , Humanos , Ratones , Colitis/patología , Factores de Transcripción Forkhead/metabolismo , Inflamación/patología , Enfermedades Inflamatorias del Intestino/patología , Interleucina-23/metabolismo , Linfocitos T ReguladoresRESUMEN
Stomach cancer is a leading cause of cancer death. Helicobacter pylori is a bacterial gastric pathogen that is the primary risk factor for carcinogenesis, associated with its induction of inflammation and DNA damage. Dicarbonyl electrophiles are generated from lipid peroxidation during the inflammatory response and form covalent adducts with amine-containing macromolecules. 2-hydroxybenzylamine (2-HOBA) is a natural compound derived from buckwheat seeds and acts as a potent scavenger of reactive aldehydes. Our goal was to investigate the effect of 2-HOBA on the pathogenesis of H. pylori infection. We used transgenic FVB/N insulin-gastrin (INS-GAS) mice as a model of gastric cancer. First, we found that 2-HOBA is bioavailable in the gastric tissues of these mice after supplementation in the drinking water. Moreover, 2-HOBA reduced the development of gastritis in H. pylori-infected INS-GAS mice without affecting the bacterial colonization level in the stomach. Further, we show that the development of gastric dysplasia and carcinoma was significantly reduced by 2-HOBA. Concomitantly, DNA damage were also inhibited by 2-HOBA treatment in H. pylori-infected mice. In parallel, DNA damage was inhibited by 2-HOBA in H. pylori-infected gastric epithelial cells in vitro. In conclusion, 2-HOBA, which has been shown to be safe in human clinical trials, represents a promising nutritional compound for the chemoprevention of the more severe effects of H. pylori infection.
Asunto(s)
Gastritis , Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Ratones , Animales , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/prevención & control , Neoplasias Gástricas/etiología , Gastritis/tratamiento farmacológico , Gastrinas , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Mucosa Gástrica/patologíaRESUMEN
Colonization by Helicobacter pylori is associated with gastric diseases, ranging from superficial gastritis to more severe pathologies, including intestinal metaplasia and adenocarcinoma. The interplay of the host response and the pathogen affect the outcome of disease. One major component of the mucosal response to H. pylori is the activation of a strong but inefficient immune response that fails to control the infection and frequently causes tissue damage. We have shown that polyamines can regulate H. pylori-induced inflammation. Chemical inhibition of ornithine decarboxylase (ODC), which generates the polyamine putrescine from l-ornithine, reduces gastritis in mice and adenocarcinoma incidence in gerbils infected with H. pylori However, we have also demonstrated that Odc deletion in myeloid cells enhances M1 macrophage activation and gastritis. Here we used a genetic approach to assess the specific role of gastric epithelial ODC during H. pylori infection. Specific deletion of the gene encoding for ODC in gastric epithelial cells reduces gastritis, attenuates epithelial proliferation, alters the metabolome, and downregulates the expression of immune mediators induced by H. pylori Inhibition of ODC activity or ODC knockdown in human gastric epithelial cells dampens H. pylori-induced NF-κB activation, CXCL8 mRNA expression, and IL-8 production. Chronic inflammation is a major risk factor for the progression to more severe pathologies associated with H. pylori infection, and we now show that epithelial ODC plays an important role in mediating this inflammatory response.
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Adenocarcinoma , Gastritis , Infecciones por Helicobacter , Helicobacter pylori , Adenocarcinoma/metabolismo , Animales , Células Epiteliales/metabolismo , Mucosa Gástrica/patología , Helicobacter pylori/metabolismo , Humanos , Inflamación/metabolismo , Ratones , Ornitina Descarboxilasa/genética , Ornitina Descarboxilasa/metabolismoRESUMEN
Macrophages play a crucial role in the inflammatory response to the human stomach pathogen Helicobacter pylori, which infects half of the world's population and causes gastric cancer. Recent studies have highlighted the importance of macrophage immunometabolism in their activation state and function. We have demonstrated that the cysteine-producing enzyme cystathionine γ-lyase (CTH) is upregulated in humans and mice with H. pylori infection. Here, we show that induction of CTH in macrophages by H. pylori promoted persistent inflammation. Cth-/- mice had reduced macrophage and T cell activation in H. pylori-infected tissues, an altered metabolome, and decreased enrichment of immune-associated gene networks, culminating in decreased H. pylori-induced gastritis. CTH is downstream of the proposed antiinflammatory molecule, S-adenosylmethionine (SAM). Whereas Cth-/- mice exhibited gastric SAM accumulation, WT mice treated with SAM did not display protection against H. pylori-induced inflammation. Instead, we demonstrated that Cth-deficient macrophages exhibited alterations in the proteome, decreased NF-κB activation, diminished expression of macrophage activation markers, and impaired oxidative phosphorylation and glycolysis. Thus, through altering cellular respiration, CTH is a key enhancer of macrophage activation, contributing to a pathogenic inflammatory response that is the universal precursor for the development of H. pylori-induced gastric disease.
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Infecciones por Helicobacter , Helicobacter pylori , Animales , Cistationina gamma-Liasa/genética , Cistationina gamma-Liasa/metabolismo , Inflamación/metabolismo , Macrófagos/metabolismo , RatonesRESUMEN
Gastric carcinogenesis is mediated by complex interactions among Helicobacter pylori, host, and environmental factors. Here, we demonstrate that H. pylori augmented gastric injury in INS-GAS mice under iron-deficient conditions. Mechanistically, these phenotypes were not driven by alterations in the gastric microbiota; however, discovery-based and targeted metabolomics revealed that bile acids were significantly altered in H. pylori-infected mice with iron deficiency, with significant upregulation of deoxycholic acid (DCA), a carcinogenic bile acid. The severity of gastric injury was further augmented when H. pylori-infected mice were treated with DCA, and, in vitro, DCA increased translocation of the H. pylori oncoprotein CagA into host cells. Conversely, bile acid sequestration attenuated H. pylori-induced injury under conditions of iron deficiency. To translate these findings to human populations, we evaluated the association between bile acid sequestrant use and gastric cancer risk in a large human cohort. Among 416,885 individuals, a significant dose-dependent reduction in risk was associated with cumulative bile acid sequestrant use. Further, expression of the bile acid receptor transmembrane G protein-coupled bile acid receptor 5 (TGR5) paralleled the severity of carcinogenic lesions in humans. These data demonstrate that increased H. pylori-induced injury within the context of iron deficiency is tightly linked to altered bile acid metabolism, which may promote gastric carcinogenesis.
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Infecciones por Helicobacter , Helicobacter pylori , Deficiencias de Hierro , Neoplasias Gástricas , Animales , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Ácidos y Sales Biliares/metabolismo , Carcinogénesis/metabolismo , Mucosa Gástrica/metabolismo , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/metabolismo , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Humanos , Inflamación/patología , Ratones , Neoplasias Gástricas/genéticaRESUMEN
BACKGROUND & AIMS: Because inflammatory bowel disease is increasing worldwide and can lead to colitis-associated carcinoma (CAC), new interventions are needed. We have shown that spermine oxidase (SMOX), which generates spermidine (Spd), regulates colitis. Here we determined whether Spd treatment reduces colitis and carcinogenesis. METHODS: SMOX was quantified in human colitis and associated dysplasia using quantitative reverse-transcription polymerase chain reaction and immunohistochemistry. We used wild-type (WT) and Smox-/- C57BL/6 mice treated with dextran sulfate sodium (DSS) or azoxymethane (AOM)-DSS as models of colitis and CAC, respectively. Mice with epithelial-specific deletion of Apc were used as a model of sporadic colon cancer. Animals were supplemented or not with Spd in the drinking water. Colonic polyamines, inflammation, tumorigenesis, transcriptomes, and microbiomes were assessed. RESULTS: SMOX messenger RNA levels were decreased in human ulcerative colitis tissues and inversely correlated with disease activity, and SMOX protein was reduced in colitis-associated dysplasia. DSS colitis and AOM-DSS-induced dysplasia and tumorigenesis were worsened in Smox-/- vs WT mice and improved in both genotypes with Spd. Tumor development caused by Apc deletion was also reduced by Spd. Smox deletion and AOM-DSS treatment were both strongly associated with increased expression of α-defensins, which was reduced by Spd. A shift in the microbiome, with reduced abundance of Prevotella and increased Proteobacteria and Deferribacteres, occurred in Smox-/- mice and was reversed with Spd. CONCLUSIONS: Loss of SMOX is associated with exacerbated colitis and CAC, increased α-defensin expression, and dysbiosis of the microbiome. Spd supplementation reverses these phenotypes, indicating that it has potential as an adjunctive treatment for colitis and chemopreventive for colon carcinogenesis.
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Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Colitis/genética , Neoplasias del Colon/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Espermidina/uso terapéutico , Proteína de la Poliposis Adenomatosa del Colon/genética , Animales , Azoximetano , Colitis/inducido químicamente , Colitis/enzimología , Colitis/prevención & control , Colitis Ulcerosa/enzimología , Colitis Ulcerosa/genética , Colon/enzimología , Colon/patología , Neoplasias del Colon/prevención & control , Sulfato de Dextran , Microbioma Gastrointestinal/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Mucosa Intestinal/enzimología , Mucosa Intestinal/patología , Masculino , Ratones , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Lesiones Precancerosas/enzimología , Factores Protectores , ARN Mensajero/metabolismo , Índice de Severidad de la Enfermedad , Espermidina/metabolismo , Espermidina/farmacología , Pérdida de Peso/efectos de los fármacos , alfa-Defensinas/genética , alfa-Defensinas/metabolismo , Poliamino OxidasaRESUMEN
CCL11, also known as eotaxin-1, is described as an eosinophil chemoattractant, which has been implicated in allergic and Th2 inflammatory diseases. We have reported that CCL11 is significantly increased in the serum of inflammatory bowel disease (IBD) patients, colonic eosinophils are increased and correlate with tissue CCL11 levels in ulcerative colitis patients, and CCL11 is increased in dextran sulfate sodium (DSS)-induced murine colitis. Here, we show that CCL11 is involved in the pathogenesis of DSS-induced colitis and in colon tumorigenesis in the azoxymethane (AOM)-DSS model of colitis-associated carcinogenesis (CAC). Ccl11-/- mice exposed to DSS then allowed to recover had significantly less body weight loss and a decrease in histologic injury versus wild-type (WT) mice. In the AOM-DSS model, Ccl11-/- mice exhibited decreased colonic tumor number and burden, histologic injury, and colonic eosinophil infiltration versus WT mice. Ccl11 is expressed by both colonic epithelial and lamina propria immune cells. Studies in bone marrow chimera mice revealed that hematopoietic- and epithelial-cell-derived CCL11 were both important for tumorigenesis in the AOM-DSS model. These findings indicate that CCL11 is important in the regulation of colitis and associated carcinogenesis and thus anti-CCL11 antibodies may be useful for treatment and cancer chemoprevention in IBD.
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Carcinogénesis/patología , Quimiocina CCL11/fisiología , Neoplasias Asociadas a Colitis/patología , Colitis/complicaciones , Células Epiteliales/patología , Animales , Azoximetano/toxicidad , Carcinogénesis/metabolismo , Carcinógenos/toxicidad , Colitis/inducido químicamente , Neoplasias Asociadas a Colitis/etiología , Neoplasias Asociadas a Colitis/metabolismo , Células Epiteliales/metabolismo , Ratones , Ratones NoqueadosRESUMEN
BACKGROUND & AIMS: Inflammation in the gastrointestinal tract may lead to the development of cancer. Dicarbonyl electrophiles, such as isolevuglandins (isoLGs), are generated from lipid peroxidation during the inflammatory response and form covalent adducts with amine-containing macromolecules. Thus, we sought to determine the role of dicarbonyl electrophiles in inflammation-associated carcinogenesis. METHODS: The formation of isoLG adducts was analyzed in the gastric tissues of patients infected with Helicobacter pylori from gastritis to precancerous intestinal metaplasia, in human gastric organoids, and in patients with colitis and colitis-associated carcinoma (CAC). The effect on cancer development of a potent scavenger of dicarbonyl electrophiles, 5-ethyl-2-hydroxybenzylamine (EtHOBA), was determined in transgenic FVB/N insulin-gastrin (INS-GAS) mice and Mongolian gerbils as models of H pylori-induced carcinogenesis and in C57BL/6 mice treated with azoxymethane-dextran sulfate sodium as a model of CAC. The effect of EtHOBA on mutations in gastric epithelial cells of H pylori-infected INS-GAS mice was assessed by whole-exome sequencing. RESULTS: We show increased isoLG adducts in gastric epithelial cell nuclei in patients with gastritis and intestinal metaplasia and in human gastric organoids infected with H pylori. EtHOBA inhibited gastric carcinoma in infected INS-GAS mice and gerbils and attenuated isoLG adducts, DNA damage, and somatic mutation frequency. Additionally, isoLG adducts were elevated in tissues from patients with colitis, colitis-associated dysplasia, and CAC as well as in dysplastic tumors of C57BL/6 mice treated with azoxymethane-dextran sulfate sodium. In this model, EtHOBA significantly reduced adduct formation, tumorigenesis, and dysplasia severity. CONCLUSIONS: Dicarbonyl electrophiles represent a link between inflammation and somatic genomic alterations and are thus key targets for cancer chemoprevention.
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Transformación Celular Neoplásica/inmunología , Neoplasias Asociadas a Colitis/inmunología , Lípidos/inmunología , Lesiones Precancerosas/inmunología , Neoplasias Gástricas/inmunología , Animales , Bencilaminas/farmacología , Bencilaminas/uso terapéutico , Núcleo Celular/metabolismo , Transformación Celular Neoplásica/efectos de los fármacos , Neoplasias Asociadas a Colitis/microbiología , Neoplasias Asociadas a Colitis/patología , Neoplasias Asociadas a Colitis/prevención & control , Modelos Animales de Enfermedad , Células Epiteliales , Mucosa Gástrica/citología , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/inmunología , Mucosa Gástrica/patología , Gastritis/inmunología , Gastritis/microbiología , Gastritis/patología , Gerbillinae , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/inmunología , Helicobacter pylori/aislamiento & purificación , Humanos , Lípidos/antagonistas & inhibidores , Metaplasia/inmunología , Metaplasia/microbiología , Metaplasia/patología , Ratones , Ratones Transgénicos , Organoides , Lesiones Precancerosas/tratamiento farmacológico , Lesiones Precancerosas/microbiología , Lesiones Precancerosas/patología , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/prevención & controlRESUMEN
Innate responses of myeloid cells defend against pathogenic bacteria via inducible effectors. Deoxyhypusine synthase (DHPS) catalyzes the transfer of the N-moiety of spermidine to the lysine-50 residue of eukaryotic translation initiation factor 5A (EIF5A) to form the amino acid hypusine. Hypusinated EIF5A (EIF5AHyp) transports specific mRNAs to ribosomes for translation. We show that DHPS is induced in macrophages by two gastrointestinal pathogens, Helicobacter pylori and Citrobacter rodentium, resulting in enhanced hypusination of EIF5A. EIF5AHyp was also increased in gastric macrophages from patients with H. pylori gastritis. Furthermore, we identify the bacteria-induced immune effectors regulated by hypusination. This set of proteins includes essential constituents of antimicrobial response and autophagy. Mice with myeloid cell-specific deletion of Dhps exhibit reduced EIF5AHyp in macrophages and increased bacterial burden and inflammation. Thus, regulation of translation through hypusination is a critical hallmark of the defense of eukaryotic hosts against pathogenic bacteria.
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Antiinfecciosos/uso terapéutico , Lisina/análogos & derivados , Macrófagos/inmunología , Animales , Antiinfecciosos/farmacología , Modelos Animales de Enfermedad , Humanos , Lisina/uso terapéutico , RatonesRESUMEN
BACKGROUND & AIMS: Countries endemic for parasitic infestations have a lower incidence of Crohn's disease (CD) than nonendemic countries, and there have been anecdotal reports of the beneficial effects of helminths in CD patients. Tuft cells in the small intestine sense and direct the immune response against eukaryotic parasites. We investigated the activities of tuft cells in patients with CD and mouse models of intestinal inflammation. METHODS: We used microscopy to quantify tuft cells in intestinal specimens from patients with ileal CD (n = 19), healthy individuals (n = 14), and TNFΔARE/+ mice, which develop Crohn's-like ileitis. We performed single-cell RNA sequencing, mass spectrometry, and microbiome profiling of intestinal tissues from wild-type and Atoh1-knockout mice, which have expansion of tuft cells, to study interactions between microbes and tuft cell populations. We assessed microbe dependence of tuft cell populations using microbiome depletion, organoids, and microbe transplant experiments. We used multiplex imaging and cytokine assays to assess alterations in inflammatory response following expansion of tuft cells with succinate administration in TNFΔARE/+ and anti-CD3E CD mouse models. RESULTS: Inflamed ileal tissues from patients and mice had reduced numbers of tuft cells, compared with healthy individuals or wild-type mice. Expansion of tuft cells was associated with increased expression of genes that regulate the tricarboxylic acid cycle, which resulted from microbe production of the metabolite succinate. Experiments in which we manipulated the intestinal microbiota of mice revealed the existence of an ATOH1-independent population of tuft cells that was sensitive to metabolites produced by microbes. Administration of succinate to mice expanded tuft cells and reduced intestinal inflammation in TNFΔARE/+ mice and anti-CD3E-treated mice, increased GATA3+ cells and type 2 cytokines (IL22, IL25, IL13), and decreased RORGT+ cells and type 17 cytokines (IL23) in a tuft cell-dependent manner. CONCLUSIONS: We found that tuft cell expansion reduced chronic intestinal inflammation in mice. Strategies to expand tuft cells might be developed for treatment of CD.
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Células Quimiorreceptoras/inmunología , Enfermedad de Crohn/inmunología , Microbioma Gastrointestinal/inmunología , Ileítis/inmunología , Mucosa Intestinal/inmunología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Células Quimiorreceptoras/patología , Enfermedad de Crohn/microbiología , Enfermedad de Crohn/patología , ADN Bacteriano/genética , Modelos Animales de Enfermedad , Heces/microbiología , Femenino , Humanos , Ileítis/microbiología , Ileítis/patología , Íleon/citología , Íleon/inmunología , Íleon/microbiología , Íleon/patología , Mucosa Intestinal/citología , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Noqueados , Factores Protectores , ARN Ribosómico 16S/genética , RNA-Seq , Análisis de la Célula Individual , Ácido Succínico/inmunología , Ácido Succínico/metabolismoRESUMEN
A tumor blood vessel is a key regulator of tissue perfusion, immune cell trafficking, cancer metastasis, and therapeutic responsiveness. mTORC1 is a signaling node downstream of multiple angiogenic factors in the endothelium. However, mTORC1 inhibitors have limited efficacy in most solid tumors, in part due to inhibition of immune function at high doses used in oncology patients and compensatory PI3K signaling triggered by mTORC1 inhibition in tumor cells. Here we show that low-dose RAD001/everolimus, an mTORC1 inhibitor, selectively targets mTORC1 signaling in endothelial cells (ECs) without affecting tumor cells or immune cells, resulting in tumor vessel normalization and increased antitumor immunity. Notably, this phenotype was recapitulated upon targeted inducible gene ablation of the mTORC1 component Raptor in tumor ECs (RaptorECKO). Tumors grown in RaptorECKO mice displayed a robust increase in tumor-infiltrating lymphocytes due to GM-CSF-mediated activation of CD103+ dendritic cells and displayed decreased tumor growth and metastasis. GM-CSF neutralization restored tumor growth and metastasis, as did T cell depletion. Importantly, analyses of human tumor data sets support our animal studies. Collectively, these findings demonstrate that endothelial mTORC1 is an actionable target for tumor vessel normalization, which could be leveraged to enhance antitumor immune therapies.
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Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Everolimus/farmacología , Linfocitos Infiltrantes de Tumor/inmunología , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Pulmonar de Lewis/inmunología , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patología , Endotelio Vascular/inmunología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Transducción de SeñalRESUMEN
Helicobacter pylori infection is the main risk factor for the development of gastric cancer, the third leading cause of cancer death worldwide. H. pylori colonizes the human gastric mucosa and persists for decades. The inflammatory response is ineffective in clearing the infection, leading to disease progression that may result in gastric adenocarcinoma. We have shown that polyamines are regulators of the host response to H. pylori, and that spermine oxidase (SMOX), which metabolizes the polyamine spermine into spermidine plus H2O2, is associated with increased human gastric cancer risk. We now used a molecular approach to directly address the role of SMOX, and demonstrate that Smox-deficient mice exhibit significant reductions of gastric spermidine levels and H. pylori-induced inflammation. Proteomic analysis revealed that cancer was the most significantly altered functional pathway in Smox-/- gastric organoids. Moreover, there was also less DNA damage and ß-catenin activation in H. pylori-infected Smox-/- mice or gastric organoids, compared to infected wild-type animals or gastroids. The link between SMOX and ß-catenin activation was confirmed in human gastric organoids that were treated with a novel SMOX inhibitor. These findings indicate that SMOX promotes H. pylori-induced carcinogenesis by causing inflammation, DNA damage, and activation of ß-catenin signaling.
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Adenocarcinoma/etiología , Daño del ADN , Gastritis/enzimología , Infecciones por Helicobacter/enzimología , Helicobacter pylori/patogenicidad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/fisiología , Espermina/metabolismo , Neoplasias Gástricas/etiología , Adenocarcinoma/microbiología , Animales , Transformación Celular Neoplásica , Gastritis/genética , Gastritis/microbiología , Gastritis/patología , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Organoides , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/deficiencia , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Proteoma , ARN Mensajero/biosíntesis , Transducción de Señal , Espermidina/biosíntesis , Neoplasias Gástricas/microbiología , beta Catenina/fisiología , Poliamino OxidasaRESUMEN
Crohn's disease (CD) has been associated with an increased consumption of n-6 polyunsaturated fatty acid (PUFA), while greater intake of n-3 PUFA has been associated with a reduced risk. We sought to investigate serum fatty acid composition in CD, and associations of fatty acids with disease activity, cytokines, and adipokines. Serum was prospectively collected from 116 CD subjects and 27 non-IBD controls. Clinical disease activity was assessed by the Harvey Bradshaw Index (HBI). Serum fatty acids were measured by gas chromatography. Serum cytokines and adipokines were measured by Luminex assay. Dietary histories were obtained from a subset of patients. Nine serum cytokines and adipokines were increased in CD versus controls. CD subjects had increased percentage serum monounsaturated fatty acids (MUFA), dihomo-gamma linolenic acid (DGLA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and oleic acid, but decreased arachidonic acid (AA) versus controls. The % total n-3 fatty acids and % EPA directly correlated with pro-inflammatory cytokine levels and HBI, whereas the % total n-6 fatty acids were inversely correlated with pro-inflammatory cytokine levels and HBI. CD subjects had increased caloric intake versus controls, but no alterations in total fat or PUFA intake. We found differences in serum fatty acids, most notably PUFA, in CD that correlated both with clinical disease activity and inflammatory cytokines. Our findings indicate that altered fatty acid metabolism or utilization is present in CD and is related to disease activity.
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Adipoquinas/sangre , Biomarcadores/sangre , Enfermedad de Crohn/patología , Citocinas/sangre , Ácidos Grasos Insaturados/sangre , Mediadores de Inflamación/sangre , Adulto , Estudios de Casos y Controles , Enfermedad de Crohn/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Índice de Severidad de la EnfermedadRESUMEN
Solute carrier family 7 member 2 (SLC7A2, also known as CAT2) is an inducible transporter of the semi-essential amino acid L-arginine (L-Arg), which has been implicated in wound repair. We have reported that both SLC7A2 expression and L-Arg availability are decreased in colonic tissues from inflammatory bowel disease patients and that mice lacking Slc7a2 exhibit a more severe disease course when exposed to dextran sulfate sodium (DSS) compared to wild-type (WT) mice. Here, we present evidence that SLC7A2 plays a role in modulating colon tumorigenesis in the azoxymethane (AOM)-DSS model of colitis-associated carcinogenesis (CAC). SLC7A2 was localized predominantly to colonic epithelial cells in WT mice. Utilizing the AOM-DSS model, Slc7a2-/- mice had significantly increased tumor number, burden, and risk of high-grade dysplasia vs. WT mice. Tumors from Slc7a2-/- mice exhibited significantly increased levels of the proinflammatory cytokines/chemokines IL-1ß, CXCL1, CXCL5, IL-3, CXCL2, CCL3, and CCL4, but decreased levels of IL-4, CXCL9, and CXCL10 compared to tumors from WT mice. This was accompanied by a shift toward pro-tumorigenic M2 macrophage activation in Slc7a2-deficient mice, as marked by increased colonic CD11b+F4/80+ARG1+ cells with no alteration in CD11b+F4/80+NOS2+ cells by flow cytometry and immunofluorescence microscopy. The shift toward M2 macrophage activation was confirmed in bone marrow-derived macrophages from Slc7a2-/- mice. In bone marrow chimeras between Slc7a2-/- and WT mice, the recipient genotype drove the CAC phenotype, suggesting the importance of epithelial SLC7A2 in abrogating neoplastic risk. These data reveal that SLC7A2 has a significant role in the protection from CAC in the setting of chronic colitis, and suggest that the decreased SLC7A2 in inflammatory bowel disease (IBD) may contribute to CAC risk. Strategies to enhance L-Arg availability by supplementing L-Arg and/or increasing L-Arg uptake could represent a therapeutic approach in IBD to reduce the substantial long-term risk of colorectal carcinoma.