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1.
Nat Commun ; 11(1): 4950, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009377

RESUMO

Necrotizing enterocolitis (NEC) is a devastating disease of premature infants with high mortality rate, indicating the need for precision treatment. NEC is characterized by intestinal inflammation and ischemia, as well derangements in intestinal microcirculation. Remote ischemic conditioning (RIC) has emerged as a promising tool in protecting distant organs against ischemia-induced damage. However, the effectiveness of RIC against NEC is unknown. To address this gap, we aimed to determine the efficacy and mechanism of action of RIC in experimental NEC. NEC was induced in mouse pups between postnatal day (P) 5 and 9. RIC was applied through intermittent occlusion of hind limb blood flow. RIC, when administered in the early stages of disease progression, decreases intestinal injury and prolongs survival. The mechanism of action of RIC involves increasing intestinal perfusion through vasodilation mediated by nitric oxide and hydrogen sulfide. RIC is a viable and non-invasive treatment strategy for NEC.


Assuntos
Enterocolite Necrosante/patologia , Intestinos/irrigação sanguínea , Intestinos/patologia , Isquemia/patologia , Microcirculação , Animais , Enterócitos/patologia , Humanos , Hipóxia , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Microvilosidades/patologia , Microvilosidades/ultraestrutura
2.
Nat Commun ; 11(1): 4766, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958778

RESUMO

Germline telomere maintenance defects are associated with an increased incidence of inflammatory diseases in humans, yet whether and how telomere dysfunction causes inflammation are not known. Here, we show that telomere dysfunction drives pATM/c-ABL-mediated activation of the YAP1 transcription factor, up-regulating the major pro-inflammatory factor, pro-IL-18. The colonic microbiome stimulates cytosolic receptors activating caspase-1 which cleaves pro-IL-18 into mature IL-18, leading to recruitment of interferon (IFN)-γ-secreting T cells and intestinal inflammation. Correspondingly, patients with germline telomere maintenance defects exhibit DNA damage (γH2AX) signaling together with elevated YAP1 and IL-18 expression. In mice with telomere dysfunction, telomerase reactivation in the intestinal epithelium or pharmacological inhibition of ATM, YAP1, or caspase-1 as well as antibiotic treatment, dramatically reduces IL-18 and intestinal inflammation. Thus, telomere dysfunction-induced activation of the ATM-YAP1-pro-IL-18 pathway in epithelium is a key instigator of tissue inflammation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Inflamação/patologia , Telômero/patologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antibacterianos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Caspase 1/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Criança , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Gastroenteropatias/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/microbiologia , Interleucina-18/genética , Interleucina-18/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Mutantes , Fosforilação , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Transdução de Sinais , Telomerase/genética , Telomerase/metabolismo
3.
Vet Pathol ; 57(5): 642-652, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32880235

RESUMO

In the small intestine, localized innate mucosal immunity is critical for intestinal homeostasis. Porcine epidemic diarrhea virus (PEDV) infection induces villus injury and impairs digestive function. Moreover, the infection might comprise localized innate mucosal immunity. This study investigated specific enterocyte subtypes and innate immune components of weaned pigs during PEDV infection. Four-week-old pigs were orally inoculated with PEDV IN19338 strain (n = 40) or sham-inoculated (n = 24). At day post inoculation (DPI) 2, 4, and 6, lysozyme expression in Paneth cells, cellular density of villous and Peyer's patch microfold (M) cells, and the expression of polymeric immunoglobulin receptor (pIgR) were assessed in the jejunum and ileum by immunohistochemistry, and interleukin (IL)-1ß and tumor necrosis factor (TNF)-α were measured in the jejunum by ELISA. PEDV infection led to a decrease in the ratios of villus height to crypt depth (VH-CD) in jejunum at DPI 2, 4, and 6 and in ileum at DPI 4. The number of villous M cells was reduced in jejunum at DPI 4 and 6 and in ileum at DPI 6, while the number of Peyer's patch M cells in ileum increased at DPI 2 and then decreased at DPI 6. PEDV-infected pigs also had reduced lysozyme expression in ileal Paneth cells at DPI 2 and increased ileal pIgR expression at DPI 4. There were no significant changes in IL-1ß and TNF-α expression in PEDV-infected pigs compared to controls. In conclusion, PEDV infection affected innate mucosal immunity of weaned pigs through alterations in Paneth cells, villous and Peyer's patch M cells, and pIgR expression.


Assuntos
Infecções por Coronavirus/veterinária , Imunidade Inata , Mucosa Intestinal/imunologia , Vírus da Diarreia Epidêmica Suína , Animais , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Citocinas/análise , Íleo/imunologia , Íleo/patologia , Íleo/virologia , Mucosa Intestinal/química , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Jejuno/imunologia , Jejuno/patologia , Jejuno/virologia , Receptores de Imunoglobulina Polimérica/metabolismo , Suínos , Desmame
4.
Adv Exp Med Biol ; 1265: 133-151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32761574

RESUMO

The intestine interacts with a diverse community of antigens and bacteria. To keep its homeostasis, the gut has evolved with a complex defense system, including intestinal microbiota, epithelial layer and lamina propria. Various factors (e.g., nutrients) affect the intestinal defensive system and progression of intestinal diseases. This review highlights the current understanding about the role of amino acids (AAs) in protecting the intestine from harm. Amino acids (e.g., arginine, glutamine and tryptophan) are essential for the function of intestinal microbiota, epithelial cells, tight junction, goblet cells, Paneth cells and immune cells (e.g., macrophages, B cells and T cells). Through the modulation of the intestinal defensive system, AAs maintain the integrity and function of the intestinal mucosa and inhibit the progression of various intestinal diseases (e.g., intestinal infection and intestinal colitis). Thus, adequate intake of functional AAs is crucial for intestinal and whole-body health in humans and other animals.


Assuntos
Aminoácidos/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Animais , Colite , Microbioma Gastrointestinal , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Junções Íntimas
5.
PLoS One ; 15(8): e0237699, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810175

RESUMO

Bowel health is an important factor for duck rearing that has been linked to feed uptake and growth and death rates. Because the regulatory networks associated with acute stress-mediated injury in the duck gastrointestinal tract have not clearly elucidated, we aimed to explore potential miRNA-mRNA pairs and their regulatory roles in oxidative stress injury caused by transport stress. Here, 1-day-old mallard ducklings from the same breeder flock were collected and transported for 8 h, whereas the control group was not being transported. Various parameters reflecting oxidative stress and the tissue appearance of the intestine were assessed. The data showed that the plasma T-AOC and SOD concentrations were decreased in the transported ducklings. The intestine of the transported ducklings also displayed significant damage. High-throughput sequencing of the intestine revealed 44 differentially expressed miRNAs and 75 differentially expressed genes, which constituted 344 miRNA-mRNA pairs. KEGG pathway analysis revealed that the metabolic, FoxO signaling, influenza A and TGF-ß signaling pathways were mainly involved in the mechanism underlying the induction of intestinal damage induced by simulated transport stress in ducks. A miRNA-mRNA pair, miR-217-5p/CHRDL1, was selected to validate the miRNA-mRNA negative relationship, and the results showed that miR-217-5p could influence CHRDL1 expression. This study provides new useful information for future research on the regulatory network associated with mucosal damage in the duck intestine.


Assuntos
Patos/fisiologia , Mucosa Intestinal/patologia , MicroRNAs/metabolismo , Estresse Oxidativo/genética , Transportes , Criação de Animais Domésticos , Animais , Redes Reguladoras de Genes , Mucosa Intestinal/metabolismo , RNA Mensageiro/metabolismo , RNA-Seq , Transdução de Sinais/genética
6.
Ecotoxicol Environ Saf ; 204: 111072, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32758694

RESUMO

Zearalenone (ZEN) is a mycotoxin that causes serious health problems in humans and animals. However, few studies have focused on the destruction of the intestinal barrier caused by ZEN. In this study, rats were exposed to different dosages of ZEN (0, 0.2, 1.0 and 5.0 mg/kg bw) by gavage for 4 weeks. The results showed that 1.0 and 5.0 mg/kg ZEN impaired gut morphology, induced the inflammatory response, reduced mucin expression, increased intestinal permeability, decreased the expression of TJ proteins and activated the RhoA/ROCK pathway. However, 0.2 mg/kg ZEN had no significant effect on intestinal barrier except for reducing the expression of some TJ proteins and mucins. Moreover, exposure to ZEN led to slight imbalance in microbiota. In conclusion, ZEN exposure resulted in intestinal barrier dysfunction by inducing intestinal microbiota dysbiosis, decreasing the expression of TJ proteins, activating the RhoA/ROCK pathway, and inducing the inflammatory response.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Zearalenona/toxicidade , Animais , Relação Dose-Resposta a Droga , Disbiose/induzido quimicamente , Feminino , Microbioma Gastrointestinal/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Jejuno/microbiologia , Jejuno/patologia , Masculino , Mucinas/metabolismo , Permeabilidade , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
9.
PLoS One ; 15(8): e0236657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760089

RESUMO

Crohn's disease is a pathological condition of the gastro-intestinal tract, causing severe transmural inflammation in the ileum and/or colon. Cigarette smoking is one of the best known environmental risk factors for the development of Crohn's disease. Nevertheless, very little is known about the effect of prolonged cigarette smoke exposure on inflammatory modulators in the gut. We examined the effect of cigarette smoke on cytokine profiles in the healthy and inflamed gut of human subjects and in the trinitrobenzene sulphonic acid mouse model, which mimics distal Crohn-like colitis. In addition, the effect of cigarette smoke on epithelial expression of transient receptor potential channels and their concurrent increase with cigarette smoke-augmented cytokine production was investigated. Active smoking was associated with increased IL-8 transcription in ileum of controls (p < 0,001; n = 18-20/group). In the ileum, TRPV1 mRNA levels were decreased in never smoking Crohn's disease patients compared to healthy subjects (p <0,001; n = 20/group). In the colon, TRPV1 mRNA levels were decreased (p = 0,046) in smoking healthy controls (n = 20/group). Likewise, healthy mice chronically exposed to cigarette smoke (n = 10/group) showed elevated ileal Cxcl2 (p = 0,0075) and colonic Kc mRNA levels (p = 0,0186), whereas TRPV1 mRNA and protein levels were elevated in the ileum (p = 0,0315). Although cigarette smoke exposure prior to trinitrobenzene sulphonic acid administration did not alter disease activity, increased pro-inflammatory cytokine production was observed in the distal colon (Kc: p = 0,0273; Cxcl2: p = 0,104; Il1-ß: p = 0,0796), in parallel with the increase of Trpv1 mRNA (p < 0,001). We infer that CS affects pro-inflammatory cytokine expression in healthy and inflamed gut, and that the simultaneous modulation of TRPV1 may point to a potential involvement of TRPV1 in cigarette smoke-induced production of inflammatory mediators.


Assuntos
Colo/metabolismo , Doença de Crohn/metabolismo , Íleo/metabolismo , Canais de Cátion TRPV/metabolismo , Fumar Tabaco/efeitos adversos , Adulto , Idoso , Animais , Células CACO-2 , Colo/patologia , Doença de Crohn/induzido quimicamente , Doença de Crohn/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células HT29 , Humanos , Íleo/patologia , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Pesquisa Médica Translacional , Ácido Trinitrobenzenossulfônico
10.
PLoS One ; 15(8): e0237182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764797

RESUMO

Necrotizing enterocolitis is the most common gastrointestinal disorder in premature neonates. This disease is characterized by massive epithelial necrosis, gut barrier dysfunction and improper mucosal defense development. Studies have shown that probiotic administration can decrease NEC incidence and mortality. The proposed mechanisms of probiotics for the prevention of NEC are: promotion of intestinal development; improved barrier function through decreased apoptosis and improved mucin production; decreased expression of proinflammatory cytokines IL6, IL8, and TNFα, and modulation of microbiota dysbiosis in preterm infants. However, reported sepsis in the immunocompromised preterm host has deterred routine prophylactic administration of probiotics in the neonatal intensive care unit. We hypothesize that maternal administration of probiotics to pregnant mouse dams can recapitulate the beneficial effects observed in neonates fed with probiotics directly. We exposed pregnant mice to the probiotics and monitored the changes in the developing intestines of the offspring. Pregnant mice were fed daily with the probiotics Lactobacillus acidophilus and Bifidobacterium infantis (LB) from embryonic day15 to 2-week-old postnatally. Intraperitoneal administration of IL-1ß in the pups was used to model proinflammatory insults. Sera were collected at 2 weeks of age and evaluated for inflammatory cytokines by enzyme-linked-immunosorbent-assay and gut permeability by Fluorescein isothiocyanate-dextran tracer assay. Ileal tissues were collected for the evaluation of apoptosis and proliferation of the intestinal epithelium; as well as mucin and tight junction integrity at mucosal surface by immunofluorescent staining. We find that maternal LB exposure facilitated intestinal epithelial cell differentiation, prevented loss of mucin and preserved the intestinal integrity and barrier function and decreased serum levels of IL-1ß, TNF-α and IL-6 in the preweaned offsprings. in LB exposed pups. We demonstrate that maternal probiotic supplementation promotes gut maturation in developing offspring. This is potentially a safe alternative therapy to induce intestinal maturation and prevent prematurity-associated neonatal disorders.


Assuntos
Enterocolite Necrosante/prevenção & controle , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/crescimento & desenvolvimento , Exposição Materna , Probióticos/administração & dosagem , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/microbiologia , Bifidobacterium longum subspecies infantis , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Enterocolite Necrosante/imunologia , Enterocolite Necrosante/microbiologia , Enterocolite Necrosante/patologia , Fezes/microbiologia , Feminino , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Interleucina-1beta/administração & dosagem , Interleucina-1beta/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Lactobacillus acidophilus , Camundongos
11.
Ecotoxicol Environ Saf ; 203: 111032, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32745774

RESUMO

Titanium dioxide nanoparticles (Np-TiO2) have become the common component of sunscreen cosmetic products. Np-TiO2 can affect especially aquatic ecosystems health, including aquatic organisms such as fish. It is therefore necessary to acquire a better understanding of the effect of Np-TiO2 on aquatic organisms. This study evaluated the biological effects of Np-TiO2 on Danio rerio, such as survival rate and weight change and, in particular, the Ti content or retention in the intestine and liver, as well as the activities of catalase and superoxide dismutase enzymes. In addition, the structure of the intestine, kidney, and liver was investigated through histological analysis. Ninety zebrafish were used, randomly divided into three treatment-groups: a control group (fed with food without adding Np-TiO2) and two groups of fish fed with food containing Np-TiO2 exposed for 7 and 14 days. The amount of Ti in the liver and intestine was measured using atomic absorption spectrophotometry coupled to a graphite furnace (GFAAS). Morphological analysis and enzyme catalase and superoxide dismutase assays were likewise performed. Ti was detected in all fish even in control group; probably Ti must have been introduced during production by the fish food industry. Structural changes were detected in fish fed with Np-TiO2 as vacuolization and disruption of the apical cytoplasm of epithelial cells that covered the intestinal villi. Although kidney morphology appeared intact, the lumen of the proximal tubule was enlarged, and the cells of the distal tubule were vacuolated. No morphological changes in the liver were detected; however, superoxide dismutase activity decreased, suggesting that liver changes occurred at the molecular level. Thus, Np-TiO2 causes morphological changes in the intestine, kidney, and liver of zebrafish and biochemical changes in the liver exposed for 7 and 14 days. Although not highly lethal, Np-TiO2 in the food chain can interfere with the morphophysiology of aquatic organisms. Neither mortalities nor body weight losses were recorded among fish in all groups over the duration of the experiment.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Bioacumulação , Catalase , Relação Dose-Resposta a Droga , Ecossistema , Cadeia Alimentar , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Nanopartículas/metabolismo , Distribuição Aleatória , Protetores Solares/química , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
14.
Nat Commun ; 11(1): 3755, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709874

RESUMO

Obesity is associated with low-grade chronic inflammation promoting insulin-resistance and diabetes. Gut microbiota dysbiosis is a consequence as well as a driver of obesity and diabetes. Mucosal-associated invariant T cells (MAIT) are innate-like T cells expressing a semi-invariant T cell receptor restricted to the non-classical MHC class I molecule MR1 presenting bacterial ligands. Here we show that during obesity MAIT cells promote inflammation in both adipose tissue and ileum, leading to insulin resistance and impaired glucose and lipid metabolism. MAIT cells act in adipose tissue by inducing M1 macrophage polarization in an MR1-dependent manner and in the gut by inducing microbiota dysbiosis and loss of gut integrity. Both MAIT cell-induced tissue alterations contribute to metabolic dysfunction. Treatment with MAIT cell inhibitory ligand demonstrates its potential as a strategy against inflammation, dysbiosis and metabolic disorders.


Assuntos
Disbiose/imunologia , Inflamação/patologia , Intestinos/patologia , Células T Invariáveis Associadas à Mucosa/patologia , Obesidade/metabolismo , Tecido Adiposo/patologia , Animais , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica , Disbiose/complicações , Microbioma Gastrointestinal , Teste de Tolerância a Glucose , Íleo/patologia , Inflamação/complicações , Mucosa Intestinal/patologia , Intestinos/diagnóstico por imagem , Ligantes , Contagem de Linfócitos , Macrófagos/metabolismo , Imagem por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/diagnóstico por imagem , Fenótipo , Pterinas/farmacologia , Receptores de Antígenos de Linfócitos T/metabolismo
15.
Nat Commun ; 11(1): 3701, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709883

RESUMO

Despite its importance in human cancers, including colorectal cancers (CRC), oncogenic KRAS has been extremely challenging to target therapeutically. To identify potential vulnerabilities in KRAS-mutated CRC, we characterize the impact of oncogenic KRAS on the cell surface of intestinal epithelial cells. Here we show that oncogenic KRAS alters the expression of a myriad of cell-surface proteins implicated in diverse biological functions, and identify many potential surface-accessible therapeutic targets. Cell surface-based loss-of-function screens reveal that ATP7A, a copper-exporter upregulated by mutant KRAS, is essential for neoplastic growth. ATP7A is upregulated at the surface of KRAS-mutated CRC, and protects cells from excess copper-ion toxicity. We find that KRAS-mutated cells acquire copper via a non-canonical mechanism involving macropinocytosis, which appears to be required to support their growth. Together, these results indicate that copper bioavailability is a KRAS-selective vulnerability that could be exploited for the treatment of KRAS-mutated neoplasms.


Assuntos
Neoplasias Colorretais/metabolismo , Cobre/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Disponibilidade Biológica , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , ATPases Transportadoras de Cobre/metabolismo , Feminino , Humanos , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos SCID , Mutação
16.
Nature ; 584(7821): 415-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641829

RESUMO

Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences1-3. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases4. Here we report that steroid signalling in Drosophila from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.


Assuntos
Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Intestinos/crescimento & desenvolvimento , Longevidade/fisiologia , Tamanho do Órgão/fisiologia , Ovário/metabolismo , Esteroides/metabolismo , Envelhecimento , Animais , Carcinogênese , Proliferação de Células , Copulação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Ecdisona/metabolismo , Feminino , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/anatomia & histologia , Intestinos/citologia , Intestinos/patologia , Masculino , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
17.
Postepy Biochem ; 66(2): 143-150, 2020 06 27.
Artigo em Polonês | MEDLINE | ID: mdl-32700508

RESUMO

Inflammatory bowel diseases are a group of chronic diseases of the digestive tract of unknown origin. The etiology of IBD is multifactorial and involves interaction between genetic, environmental and immunological factors with oxidative stress being an inherent part of any one of them. Therefore, the redox equilibrium is crucial to maintain cell homeostasis in the gastrointestinal (GI) tract, which is constantly exposed to large numbers of commensal and pathological bacteria. Distortion of this homeostasis and increase in oxidative stress leads to the propagation of inflammation, mucosal injury in the GI tract and is associated with the development and exacerbation of IBD.


Assuntos
Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Estresse Oxidativo , Homeostase , Humanos , Inflamação , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Oxirredução
18.
Nanotoxicology ; 14(7): 985-1007, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32619159

RESUMO

Recent studies reported adverse liver effects and intestinal tumor formation after oral exposure to titanium dioxide (TiO2). Other oral toxicological studies, however, observed no effects on liver and intestine, despite prolonged exposure and/or high doses. In the present assessment, we aimed to better understand whether TiO2 can induce such effects at conditions relevant for humans. Therefore, we focused not only on the clinical and histopathological observations, but also used Adverse Outcome Pathways (AOPs) to consider earlier steps (Key Events). In addition, aiming for a more accurate risk assessment, the available information on organ concentrations of Ti (resulting from exposure to TiO2) from oral animal studies was compared to recently reported concentrations found in human postmortem organs. The overview obtained with the AOP approach indicates that TiO2 can trigger a number of key events in liver and intestine: Reactive Oxygen Species (ROS) generation, induction of oxidative stress and inflammation. TiO2 seems to be able to exert these early effects in animal studies at Ti liver concentrations that are only a factor of 30 and 6 times higher than the median and highest liver concentration found in humans, respectively. This confirms earlier conclusions that adverse effects on the liver in humans as a result of (oral) TiO2 exposure cannot be excluded. Data for comparison with Ti levels in human intestinal tissue, spleen and kidney with effect concentrations were too limited to draw firm conclusions. The Ti levels, though, are similar or higher than those found in liver, suggesting these tissues may be relevant too.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas/toxicidade , Baço/efeitos dos fármacos , Titânio/toxicidade , Administração Oral , Animais , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Aditivos Alimentares/toxicidade , Humanos , Inflamação , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Titânio/química , Titânio/metabolismo
19.
DNA Cell Biol ; 39(9): 1573-1582, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32678986

RESUMO

Many immune cells participate in the pathogenesis of ulcerative colitis (UC), and fatty acid metabolism (FAM) is reported to supporting their cell-specific functions and proliferation, but the underlying mechanism is unclear. This study aimed to investigate the relationship between FAM and inflammation in colon tissues and identify potential therapeutic targets for regulating immune response. A total of 870 different expression genes (DEGs), 304 immunity-related DEGs, and 11 FAM-related DEGs were obtained, gene ontology analysis results showed that immune DEGs were significantly enriched in neutrophil migration, positive regulation of T cell activation. Fifteen types of immune cells were identified in inflamed colon tissues. Five FAM-related DEGs (ACOX1, ACSL4, ELOVL5, FADS2, and SCD) were highly correlated with immunity-related DEGs, and ACSL4, ELOVL5, and FADS2 were significantly upregulated in immune cells, while SCD is downregulated. Five FAM-related DEGs were highly correlated with immune cells. The study promotes the understanding of the pathogenesis of FAM in UC immune cells.


Assuntos
Colite Ulcerativa/genética , Ácidos Graxos/metabolismo , Redes Reguladoras de Genes , Transcriptoma , Acil-CoA Oxidase/genética , Acil-CoA Oxidase/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Colite Ulcerativa/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Linfócitos/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo
20.
Proc Natl Acad Sci U S A ; 117(32): 19376-19387, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32719140

RESUMO

Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are associated with dysbiosis of the gut microbiome. Emerging evidence suggests that small-molecule metabolites derived from bacterial breakdown of a variety of dietary nutrients confer a wide array of host benefits, including amelioration of inflammation in IBDs. Yet, in many cases, the molecular pathways targeted by these molecules remain unknown. Here, we describe roles for three metabolites-indole-3-ethanol, indole-3-pyruvate, and indole-3-aldehyde-which are derived from gut bacterial metabolism of the essential amino acid tryptophan, in regulating intestinal barrier function. We determined that these metabolites protect against increased gut permeability associated with a mouse model of colitis by maintaining the integrity of the apical junctional complex and its associated actin regulatory proteins, including myosin IIA and ezrin, and that these effects are dependent on the aryl hydrocarbon receptor. Our studies provide a deeper understanding of how gut microbial metabolites affect host defense mechanisms and identify candidate pathways for prophylactic and therapeutic treatments for IBDs.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Triptofano/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Células CACO-2 , Colite Ulcerativa/dietoterapia , Colite Ulcerativa/microbiologia , Colite Ulcerativa/patologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Humanos , Inflamação , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Miosina não Muscular Tipo IIA/metabolismo , Permeabilidade , Receptores de Hidrocarboneto Arílico/genética , Triptofano/administração & dosagem
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