Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 486
Filtrar
1.
Biomed Res Int ; 2021: 6670798, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681368

RESUMO

Recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), has led to a worldwide pandemic with millions of infected patients. Alteration in humans' microbiota was also reported in COVID-19 patients. The alteration in human microbiota may contribute to bacterial or viral infections and affect the immune system. Moreover, human's microbiota can be altered due to SARS-CoV-2 infection, and these microbiota changes can indicate the progression of COVID-19. While current studies focus on the gut microbiota, it seems necessary to pay attention to the lung microbiota in COVID-19. This study is aimed at reviewing respiratory microbiota dysbiosis among COVID-19 patients to encourage further studies on the field for assessment of SARS-CoV-2 and respiratory microbiota interaction.


Assuntos
Disbiose , Pulmão , Micobioma/imunologia , /imunologia , /imunologia , Disbiose/imunologia , Disbiose/microbiologia , Disbiose/virologia , Microbioma Gastrointestinal/imunologia , Humanos , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/virologia
2.
Nat Commun ; 12(1): 805, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547295

RESUMO

Efforts to improve the prognosis of steroid-resistant gut acute graft-versus-host-disease (SR-Gut-aGVHD) have suffered from poor understanding of its pathogenesis. Here we show that the pathogenesis of SR-Gut-aGVHD is associated with reduction of IFN-γ+ Th/Tc1 cells and preferential expansion of IL-17-IL-22+ Th/Tc22 cells. The IL-22 from Th/Tc22 cells causes dysbiosis in a Reg3γ-dependent manner. Transplantation of IFN-γ-deficient donor CD8+ T cells in the absence of CD4+ T cells produces a phenocopy of SR-Gut-aGVHD. IFN-γ deficiency in donor CD8+ T cells also leads to a PD-1-dependent depletion of intestinal protective CX3CR1hi mononuclear phagocytes (MNP), which also augments expansion of Tc22 cells. Supporting the dual regulation, simultaneous dysbiosis induction and depletion of CX3CR1hi MNP results in full-blown Gut-aGVHD. Our results thus provide insights into SR-Gut-aGVHD pathogenesis and suggest the potential efficacy of IL-22 antagonists and IFN-γ agonists in SR-Gut-aGVHD therapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Disbiose/imunologia , Doença Enxerto-Hospedeiro/imunologia , Interferon gama/imunologia , Interleucinas/imunologia , Fagócitos/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/transplante , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/imunologia , Modelos Animais de Doenças , Disbiose/genética , Disbiose/microbiologia , Disbiose/patologia , Microbioma Gastrointestinal/imunologia , Regulação da Expressão Gênica , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/microbiologia , Doença Enxerto-Hospedeiro/patologia , Interferon gama/deficiência , Interferon gama/genética , Interleucina-17/deficiência , Interleucina-17/genética , Interleucina-17/imunologia , Interleucinas/genética , Intestinos/imunologia , Intestinos/microbiologia , Intestinos/patologia , Depleção Linfocítica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas a Pancreatite/genética , Proteínas Associadas a Pancreatite/imunologia , Fagócitos/citologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais , Linfócitos T Auxiliares-Indutores , Linfócitos T Reguladores , Irradiação Corporal Total
3.
Gut ; 70(4): 698-706, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33431578

RESUMO

OBJECTIVE: Although COVID-19 is primarily a respiratory illness, there is mounting evidence suggesting that the GI tract is involved in this disease. We investigated whether the gut microbiome is linked to disease severity in patients with COVID-19, and whether perturbations in microbiome composition, if any, resolve with clearance of the SARS-CoV-2 virus. METHODS: In this two-hospital cohort study, we obtained blood, stool and patient records from 100 patients with laboratory-confirmed SARS-CoV-2 infection. Serial stool samples were collected from 27 of the 100 patients up to 30 days after clearance of SARS-CoV-2. Gut microbiome compositions were characterised by shotgun sequencing total DNA extracted from stools. Concentrations of inflammatory cytokines and blood markers were measured from plasma. RESULTS: Gut microbiome composition was significantly altered in patients with COVID-19 compared with non-COVID-19 individuals irrespective of whether patients had received medication (p<0.01). Several gut commensals with known immunomodulatory potential such as Faecalibacterium prausnitzii, Eubacterium rectale and bifidobacteria were underrepresented in patients and remained low in samples collected up to 30 days after disease resolution. Moreover, this perturbed composition exhibited stratification with disease severity concordant with elevated concentrations of inflammatory cytokines and blood markers such as C reactive protein, lactate dehydrogenase, aspartate aminotransferase and gamma-glutamyl transferase. CONCLUSION: Associations between gut microbiota composition, levels of cytokines and inflammatory markers in patients with COVID-19 suggest that the gut microbiome is involved in the magnitude of COVID-19 severity possibly via modulating host immune responses. Furthermore, the gut microbiota dysbiosis after disease resolution could contribute to persistent symptoms, highlighting a need to understand how gut microorganisms are involved in inflammation and COVID-19.


Assuntos
Bactérias , Disbiose , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal , Imunidade , Adulto , Bactérias/genética , Bactérias/imunologia , Bactérias/isolamento & purificação , Proteína C-Reativa/análise , /diagnóstico , /imunologia , Citocinas/análise , DNA Bacteriano/isolamento & purificação , Disbiose/epidemiologia , Disbiose/etiologia , Disbiose/imunologia , Disbiose/virologia , Feminino , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/virologia , Hong Kong , Humanos , Masculino , /isolamento & purificação , Índice de Gravidade de Doença , Transferases/análise
4.
Mucosal Immunol ; 14(2): 296-304, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33500564

RESUMO

Bacteria that colonize the human gastrointestinal tract are essential for good health. The gut microbiota has a critical role in pulmonary immunity and host's defense against viral respiratory infections. The gut microbiota's composition and function can be profoundly affected in many disease settings, including acute infections, and these changes can aggravate the severity of the disease. Here, we discuss mechanisms by which the gut microbiota arms the lung to control viral respiratory infections. We summarize the impact of viral respiratory infections on the gut microbiota and discuss the potential mechanisms leading to alterations of gut microbiota's composition and functions. We also discuss the effects of gut microbial imbalance on disease outcomes, including gastrointestinal disorders and secondary bacterial infections. Lastly, we discuss the potential role of the lung-gut axis in coronavirus disease 2019.


Assuntos
Microbioma Gastrointestinal , Pulmão/imunologia , Animais , Dieta , Fibras na Dieta/metabolismo , Disbiose/imunologia , Disbiose/microbiologia , Humanos , Imunidade nas Mucosas , Influenza Humana/imunologia , Probióticos , Vírus Sinciciais Respiratórios , Infecções Respiratórias
5.
Nat Commun ; 12(1): 187, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420074

RESUMO

The gut microbiota is reported to modulate the immune response in hepatocellular carcinoma (HCC). Here, we employ metagenomic and metabolomic studies to characterise gut microbiota in patients with non-alcoholic fatty liver disease (NAFLD) related cirrhosis, with or without HCC, and evaluate its effect on the peripheral immune response in an ex vivo model. We find that dysbiosis characterises the microbiota of patients with NAFLD-cirrhosis, with compositional and functional shifts occurring with HCC development. Gene function of the microbiota in NAFLD-HCC supports short chain fatty acid production, and this is confirmed by metabolomic studies. Ex vivo studies show that bacterial extracts from the NAFLD-HCC microbiota, but not from the control groups, elicit a T cell immunosuppressive phenotype, characterised by expansion of regulatory T cells and attenuation of CD8 + T cells. Our study suggest that the gut microbiota in NAFLD-HCC is characterised by a distinctive microbiome/metabolomic profile, and can modulate the peripheral immune response.


Assuntos
Carcinoma Hepatocelular/imunologia , Microbioma Gastrointestinal/imunologia , Microbioma Gastrointestinal/fisiologia , Imunidade , Neoplasias Hepáticas/imunologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Idoso , Bactérias/genética , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Citocinas , Fibras na Dieta , Disbiose/imunologia , Ácidos Graxos Voláteis/sangue , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Feminino , Humanos , Fígado/patologia , Cirrose Hepática , Neoplasias Hepáticas/patologia , Masculino , Metabolômica , Metagenômica , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Fenótipo
6.
Viruses ; 12(10)2020 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050511

RESUMO

Herd immunity is the most critical and essential prophylactic intervention that delivers protection against infectious diseases at both the individual and community level. This process of natural vaccination is immensely pertinent to the current context of a pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection around the globe. The conventional idea of herd immunity is based on efficient transmission of pathogens and developing natural immunity within a population. This is entirely encouraging while fighting against any disease in pandemic circumstances. A spatial community is occupied by people having variable resistance capacity against a pathogen. Protection efficacy against once very common diseases like smallpox, poliovirus or measles has been possible only because of either natural vaccination through contagious infections or expanded immunization programs among communities. This has led to achieving herd immunity in some cohorts. The microbiome plays an essential role in developing the body's immune cells for the emerging competent vaccination process, ensuring herd immunity. Frequency of interaction among microbiota, metabolic nutrients and individual immunity preserve the degree of vaccine effectiveness against several pathogens. Microbiome symbiosis regulates pathogen transmissibility and the success of vaccination among different age groups. Imbalance of nutrients perturbs microbiota and abrogates immunity. Thus, a particular population can become vulnerable to the infection. Intestinal dysbiosis leads to environmental enteropathy (EE). As a consequence, the generation of herd immunity can either be delayed or not start in a particular cohort. Moreover, disparities of the protective response of many vaccines in developing countries outside of developed countries are due to inconsistencies of healthy microbiota among the individuals. We suggested that pan-India poliovirus vaccination program, capable of inducing herd immunity among communities for the last 30 years, may also influence the inception of natural course of heterologous immunity against SARS-CoV-2 infection. Nonetheless, this anamnestic recall is somewhat counterintuitive, as antibody generation against original antigens of SARS-CoV-2 will be subdued due to original antigenic sin.


Assuntos
Imunidade Coletiva , Microbiota , Viroses/imunologia , Viroses/microbiologia , Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/transmissão , Disbiose/imunologia , Humanos , Imunidade Heteróloga , Imunidade Inata , Microbiota/imunologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/microbiologia , Pneumonia Viral/transmissão , Vacinação , Viroses/epidemiologia , Viroses/transmissão
7.
Crit Care ; 24(1): 537, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867808

RESUMO

During critical illness, there are a multitude of forces such as antibiotic use, mechanical ventilation, diet changes and inflammatory responses that could bring the microbiome out of balance. This so-called dysbiosis of the microbiome seems to be involved in immunological responses and may influence outcomes even in individuals who are not as vulnerable as a critically ill ICU population. It is therefore probable that dysbiosis of the microbiome is a consequence of critical illness and may, subsequently, shape an inadequate response to these circumstances.Bronchoscopic studies have revealed that the carina represents the densest site of bacterial DNA along healthy airways, with a tapering density with further bifurcations. This likely reflects the influence of micro-aspiration as the primary route of microbial immigration in healthy adults. Though bacterial DNA density grows extremely sparse at smaller airways, bacterial signal is still consistently detectable in bronchoalveolar lavage fluid, likely reflecting the fact that lavage via a wedged bronchoscope samples an enormous surface area of small airways and alveoli. The dogma of lung sterility also violated numerous observations that long predated culture-independent microbiology.The body's resident microbial consortia (gut and/or respiratory microbiota) affect normal host inflammatory and immune response mechanisms. Disruptions in these host-pathogen interactions have been associated with infection and altered innate immunity.In this narrative review, we will focus on the rationale and current evidence for a pathogenic role of the lung microbiome in the exacerbation of complications of critical illness, such as acute respiratory distress syndrome and ventilator-associated pneumonia.


Assuntos
Estado Terminal , Disbiose/imunologia , Pulmão/microbiologia , Microbiota , Humanos , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Proc Natl Acad Sci U S A ; 117(38): 23674-23683, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32907933

RESUMO

The gut microbiome has garnered attention as an effective target to boost immunity and improve cancer immunotherapy. We found that B cell-defective (BCD) mice, such as µ-membrane targeted deletion (µMT) and activation-induced cytidine deaminase (AID) knockouts (KOs), have elevated antitumor immunity under specific pathogen-free but not germ-free conditions. Microbial dysbiosis in these BCD mice enriched the type I IFN (IFN) signature in mucosal CD8+ T cells, resulting in up-regulation of the type I IFN-inducible protein stem cell antigen-1 (Sca-1). Among CD8+ T cells, naïve cells predominantly circulate from the gut to the periphery, and those that had migrated from the mesenteric lymph nodes (mLNs) to the periphery had significantly higher expression of Sca-1. The gut-educated Sca-1+ naïve subset is endowed with enhanced mitochondrial activity and antitumor effector potential. The heterogeneity and functional versatility of the systemic naïve CD8+ T cell compartment was revealed by single-cell analysis and functional assays of CD8+ T cell subpopulations. These results indicate one of the potential mechanisms through which microbial dysbiosis regulates antitumor immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Microbioma Gastrointestinal/imunologia , Interferon Tipo I/imunologia , Neoplasias Experimentais/imunologia , Animais , Antígenos Ly/imunologia , Antígenos Ly/metabolismo , Linfócitos B , Linhagem Celular Tumoral , Células Cultivadas , Disbiose/imunologia , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Interferon Tipo I/metabolismo , Linfonodos/citologia , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/imunologia
9.
Proc Natl Acad Sci U S A ; 117(40): 24998-25007, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32958643

RESUMO

Infections elicit immune adaptations to enable pathogen resistance and/or tolerance and are associated with compositional shifts of the intestinal microbiome. However, a comprehensive understanding of how infections with pathogens that exhibit distinct capability to spread and/or persist differentially change the microbiome, the underlying mechanisms, and the relative contribution of individual commensal species to immune cell adaptations is still lacking. Here, we discovered that mouse infection with a fast-spreading and persistent (but not a slow-spreading acute) isolate of lymphocytic choriomeningitis virus induced large-scale microbiome shifts characterized by increased Verrucomicrobia and reduced Firmicute/Bacteroidetes ratio. Remarkably, the most profound microbiome changes occurred transiently after infection with the fast-spreading persistent isolate, were uncoupled from sustained viral loads, and were instead largely caused by CD8 T cell responses and/or CD8 T cell-induced anorexia. Among the taxa enriched by infection with the fast-spreading virus, Akkermansia muciniphila, broadly regarded as a beneficial commensal, bloomed upon starvation and in a CD8 T cell-dependent manner. Strikingly, oral administration of A. muciniphila suppressed selected effector features of CD8 T cells in the context of both infections. Our findings define unique microbiome differences after chronic versus acute viral infections and identify CD8 T cell responses and downstream anorexia as driver mechanisms of microbial dysbiosis after infection with a fast-spreading virus. Our data also highlight potential context-dependent effects of probiotics and suggest a model in which changes in host behavior and downstream microbiome dysbiosis may constitute a previously unrecognized negative feedback loop that contributes to CD8 T cell adaptations after infections with fast-spreading and/or persistent pathogens.


Assuntos
Anorexia/imunologia , Antígenos CD8/imunologia , Memória Imunológica/imunologia , Coriomeningite Linfocítica/imunologia , Viroses/imunologia , Animais , Anorexia/microbiologia , Anorexia/virologia , Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/microbiologia , Disbiose/imunologia , Disbiose/microbiologia , Disbiose/virologia , Firmicutes/imunologia , Firmicutes/metabolismo , Microbioma Gastrointestinal/imunologia , Humanos , Coriomeningite Linfocítica/microbiologia , Coriomeningite Linfocítica/patologia , Vírus da Coriomeningite Linfocítica/patogenicidade , Camundongos , Linfócitos T/imunologia , Linfócitos T/microbiologia , Verrucomicrobia/imunologia , Verrucomicrobia/patogenicidade , Viroses/microbiologia , Viroses/patologia
10.
Front Immunol ; 11: 1582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793223

RESUMO

Metabolic abnormalities such as dyslipidemia, hyperinsulinemia, or insulin resistance and obesity play key roles in the induction and progression of type 2 diabetes mellitus (T2DM). The field of immunometabolism implies a bidirectional link between the immune system and metabolism, in which inflammation plays an essential role in the promotion of metabolic abnormalities (e.g., obesity and T2DM), and metabolic factors, in turn, regulate immune cell functions. Obesity as the main inducer of a systemic low-level inflammation is a main susceptibility factor for T2DM. Obesity-related immune cell infiltration, inflammation, and increased oxidative stress promote metabolic impairments in the insulin-sensitive tissues and finally, insulin resistance, organ failure, and premature aging occur. Hyperglycemia and the subsequent inflammation are the main causes of micro- and macroangiopathies in the circulatory system. They also promote the gut microbiota dysbiosis, increased intestinal permeability, and fatty liver disease. The impaired immune system together with metabolic imbalance also increases the susceptibility of patients to several pathogenic agents such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Thus, the need for a proper immunization protocol among such patients is granted. The focus of the current review is to explore metabolic and immunological abnormalities affecting several organs of T2DM patients and explain the mechanisms, whereby diabetic patients become more susceptible to infectious diseases.


Assuntos
Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/patologia , Hiperglicemia/imunologia , Síndrome Metabólica/imunologia , Obesidade/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Suscetibilidade a Doenças/imunologia , Disbiose/imunologia , Microbioma Gastrointestinal , Humanos , Sistema Imunitário/metabolismo , Inflamação/imunologia , Estresse Oxidativo/imunologia , Pandemias , Pneumonia Viral/imunologia
11.
Virus Res ; 286: 198103, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717345

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a major pandemic called coronavirus disease 2019 (COVID-19) that has created unprecedented global health emergencies, and emerged as a serious threat due to its strong ability for human-to-human transmission. The reports indicate the ability of SARS-CoV-2 to affect almost any organ due to the presence of a receptor known as angiotensin converting enzyme 2 (ACE2) across the body. ACE2 receptor is majorly expressed in the brush border of gut enterocytes along with the ciliated cells and alveolar epithelial type II cells in the lungs. The amino acid transport function of ACE2 has been linked to gut microbial ecology in gastrointestinal (GI) tract, thereby suggesting that COVID-19 may, to some level, be linked to the enteric microbiota. The significant number of COVID-19 patients shows extra-pulmonary symptoms in the GI tract. Many subsequent studies revealed viral RNA of SARS-CoV-2 in fecal samples of COVID-19 patients. This presents a new challenge in the diagnosis and control of COVID-19 infection with a caution for proper sanitation and hygiene. Here, we aim to discuss the immunological co-ordination between gut and lungs that facilitates SARS-CoV-2 to infect and multiply in the inflammatory bowel disease (IBD) and non-IBD patients.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Disbiose/imunologia , Trato Gastrointestinal/imunologia , Doenças Inflamatórias Intestinais/imunologia , Pulmão/imunologia , Pneumonia Viral/imunologia , Anticorpos Monoclonais/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/microbiologia , Síndrome da Liberação de Citocina/virologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/imunologia , Disbiose/tratamento farmacológico , Disbiose/microbiologia , Disbiose/virologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/virologia , Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/virologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/microbiologia , Pneumonia Viral/virologia , Receptores Virais/genética , Receptores Virais/imunologia
13.
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
14.
Oncogene ; 39(26): 4925-4943, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32514151

RESUMO

Research about the role of gut microbiome in colorectal cancer (CRC) is a newly emerging field of study. Gut microbiota modulation, with the aim to reverse established microbial dysbiosis, is a novel strategy for prevention and treatment of CRC. Different strategies including probiotics, prebiotics, postbiotics, antibiotics, and fecal microbiota transplantation (FMT) have been employed. Although these strategies show promising results, mechanistically by correcting microbiota composition, modulating innate immune system, enhancing gut barrier function, preventing pathogen colonization and exerting selective cytotoxicity against tumor cells, it should be noted that they are accompanied by risks and controversies that can potentially introduce clinical complications. During bench-to-bedside translation, evaluation of risk-and-benefit ratio, as well as patient selection, should be carefully performed. In view of the individualized host response to gut microbiome intervention, developing personalized microbiome therapy may be the key to successful clinical treatment.


Assuntos
Neoplasias Colorretais/terapia , Disbiose/imunologia , Transplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal/imunologia , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/microbiologia , Disbiose/microbiologia , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/microbiologia , Medicina de Precisão/métodos , Fatores de Risco
15.
J Food Sci ; 85(6): 1872-1890, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32460371

RESUMO

Cancer represents a major disease burden worldwide. Despite continuous advances obtained in medical therapies recently, resistance to standard drugs and adverse effects still represent important causes of therapeutic failure. There is growing evidence that the gut microbiota can affect the response to chemo- and immunotherapeutic drugs by modulating efficacy and/or toxicity, and diet is the most important factor affecting the gut microbiota. In this study, we assessed the auxiliary antitumor effects of immunomodulatory fungal proteins from Hericium erinaceus (HEP) administered with the chemotherapy drug 5-Fluorouracil (5-Fu), and we attempted to identify new potential prebiotic bacteria for auxiliary antitumor treatment. There were 1,455 proteins identified from H. erinaceus. In a xenografted mouse model of cancer, HEP with 5-Fu significantly suppressed tumor growth, inhibited inflammatory markers such as interferon (IFN)-γ, interleukin (IL)-1ß, IL-2, IL-6, tumor necrosis factor (TNF)-α, and lipopolysaccharide (LPS), and regulated the expression of Akt, CCDN1, CKD4, FOXM1, MMP7, MYC, PPAR-α, and PPAR-γ. 16S rRNA sequencing showed that HEP ameliorated the dysbacteriosis induced by 5-Fu, as it inhibited certain aerobic and microaerobic bacteria including Parabacteroides, Flavobacteriaceae, Christensenellaceae, Anoxybacillus, Aggregatibacter, Comamonadaceae, Planococcaceae, Desulfovibrionaceae, Sporosarcina, Staphylococcus, Aerococcaceae, and Bilophila in the xenografted mice, and increase some probiotic bacteria such as Bifidobacterium, Gemellales, Blautia, Sutterella, Anaerostipes, Roseburia, Lachnobacterium, Lactobacillus, and Desulfovibrio. This demonstrates that HEP could promote the antitumor efficacy of 5-Fu by improving the microbiota composition, the immune inflammatory response, and homeostasis.


Assuntos
Basidiomycota/química , Disbiose/tratamento farmacológico , Disbiose/microbiologia , Proteínas Fúngicas/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Neoplasias/microbiologia , Prebióticos/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Disbiose/induzido quimicamente , Disbiose/imunologia , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Proteínas Fúngicas/química , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
16.
Nat Commun ; 11(1): 1995, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332732

RESUMO

Gut microbial dysbiosis is associated with the development of autoimmune disease, but the mechanisms by which microbial dysbiosis affects the transition from asymptomatic autoimmunity to inflammatory disease are incompletely characterized. Here, we identify intestinal barrier integrity as an important checkpoint in translating autoimmunity to inflammation. Zonulin family peptide (zonulin), a potent regulator for intestinal tight junctions, is highly expressed in autoimmune mice and humans and can be used to predict transition from autoimmunity to inflammatory arthritis. Increased serum zonulin levels are accompanied by a leaky intestinal barrier, dysbiosis and inflammation. Restoration of the intestinal barrier in the pre-phase of arthritis using butyrate or a cannabinoid type 1 receptor agonist inhibits the development of arthritis. Moreover, treatment with the zonulin antagonist larazotide acetate, which specifically increases intestinal barrier integrity, effectively reduces arthritis onset. These data identify a preventive approach for the onset of autoimmune disease by specifically targeting impaired intestinal barrier function.


Assuntos
Artrite Reumatoide/prevenção & controle , Permeabilidade da Membrana Celular/efeitos dos fármacos , Disbiose/complicações , Haptoglobinas/antagonistas & inibidores , Mucosa Intestinal/efeitos dos fármacos , Oligopeptídeos/administração & dosagem , Precursores de Proteínas/antagonistas & inibidores , Adulto , Animais , Artrite Experimental/sangue , Artrite Experimental/imunologia , Artrite Experimental/microbiologia , Artrite Experimental/prevenção & controle , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Artrite Reumatoide/microbiologia , Translocação Bacteriana/efeitos dos fármacos , Translocação Bacteriana/imunologia , Células CACO-2 , Permeabilidade da Membrana Celular/imunologia , Estudos de Coortes , Estudos Transversais , Disbiose/imunologia , Disbiose/microbiologia , Feminino , Microbioma Gastrointestinal/imunologia , Haptoglobinas/metabolismo , Voluntários Saudáveis , Humanos , Íleo/citologia , Íleo/efeitos dos fármacos , Íleo/microbiologia , Íleo/patologia , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Precursores de Proteínas/sangue , Precursores de Proteínas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo
17.
Am J Gastroenterol ; 115(6): 814-822, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32250997

RESUMO

Primary sclerosing cholangitis (PSC) is a rare, immune-mediated, chronic cholestatic liver disease associated with a unique phenotype of inflammatory bowel disease that frequently manifests as pancolitis with right-sided predominance. Available data suggest a bidirectional interplay of the gut-liver axis with critical roles for the gastrointestinal microbiome and circulating bile acids (BAs) in the pathophysiology of PSC. BAs shape the gut microbiome, whereas gut microbes have the potential to alter BAs, and there are emerging data that alterations of BAs and the microbiome are not simply a consequence but the cause of PSC. Clustering of PSC in families may suggest that PSC occurs in genetically susceptible individuals. After exposure to an environmental trigger (e.g., microbial byproducts or BAs), an aberrant or exaggerated cholangiocyte-induced immune cascade occurs, ultimately leading to bile duct damage and progressive fibrosis. The pathophysiology can be conceptualized as a triad of (1) gut dysbiosis, (2) altered BA metabolism, and (3) immune-mediated biliary injury. Immune activation seems to be central to the disease process, but immunosuppression does not improve clinical outcomes or alter the natural history of PSC. Currently, orthoptic liver transplantation is the only established life-saving treatment, whereas antimicrobial therapy or fecal transplantation is an emerging therapeutic option for PSC. The beneficial effects of these microbiome-based therapies are likely mediated by a shift of the gut microbiome with favorable effects on BA metabolism. In the future, personalized approaches will allow to better target the interdependence between microbiome, immune function, and BA metabolism and potentially cure patients with PSC.


Assuntos
Anti-Infecciosos/uso terapêutico , Ácidos e Sais Biliares/metabolismo , Colangite Esclerosante/terapia , Disbiose/terapia , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Colangite Esclerosante/imunologia , Colangite Esclerosante/metabolismo , Colangite Esclerosante/microbiologia , Disbiose/imunologia , Disbiose/metabolismo , Transplante de Microbiota Fecal , Humanos , Imunidade nas Mucosas/imunologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Transplante de Fígado
19.
Nat Rev Gastroenterol Hepatol ; 17(5): 279-297, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32152478

RESUMO

Gut microbiota dysbiosis has been repeatedly observed in obesity and type 2 diabetes mellitus, two metabolic diseases strongly intertwined with non-alcoholic fatty liver disease (NAFLD). Animal studies have demonstrated a potential causal role of gut microbiota in NAFLD. Human studies have started to describe microbiota alterations in NAFLD and have found a few consistent microbiome signatures discriminating healthy individuals from those with NAFLD, non-alcoholic steatohepatitis or cirrhosis. However, patients with NAFLD often present with obesity and/or insulin resistance and type 2 diabetes mellitus, and these metabolic confounding factors for dysbiosis have not always been considered. Patients with different NAFLD severity stages often present with heterogeneous lesions and variable demographic characteristics (including age, sex and ethnicity), which are known to affect the gut microbiome and have been overlooked in most studies. Finally, multiple gut microbiome sequencing tools and NAFLD diagnostic methods have been used across studies that could account for discrepant microbiome signatures. This Review provides a broad insight into microbiome signatures for human NAFLD and explores issues with disentangling these signatures from underlying metabolic disorders. More advanced metagenomics and multi-omics studies using system biology approaches are needed to improve microbiome biomarkers.


Assuntos
Microbioma Gastrointestinal/imunologia , Hepatopatia Gordurosa não Alcoólica/microbiologia , Animais , Diabetes Mellitus Tipo 2/microbiologia , Doenças do Sistema Digestório/microbiologia , Disbiose/imunologia , Disbiose/microbiologia , Humanos , Hepatopatia Gordurosa não Alcoólica/imunologia , Obesidade/microbiologia , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...