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1.
Front Cell Dev Biol ; 11: 1266198, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745295

RESUMO

Autophagy is a critical protein and organelle quality control system, which regulates cellular homeostasis and survival. Growing pieces of evidence suggest that autophagic dysfunction is strongly associated with many human diseases, including neurological diseases and cancer. Among various autophagic regulators, microphthalmia (MiT)/TFE transcription factors, including transcription factor EB (TFEB), have been shown to act as the master regulators of autophagosome and lysosome biogenesis in both physiological and pathological conditions. According to the previous studies, chlorpromazine (CPZ), an FDA-approved antipsychotic drug, affects autophagy in diverse cell lines, but the underlying mechanism remains elusive. In our present study, we find that CPZ treatment induces TFEB nuclear translocation through Rag GTPases, the upstream regulators of mechanistic target of rapamycin complex 1 (mTORC1) signaling. Meanwhile, CPZ treatment also blocks autophagosome-lysosome fusion. Notably, we find a significant accumulation of immature autophagosome vesicles in CPZ-treated cells, which may impede cellular homeostasis due to the dysfunction of the autophagy-lysosome pathway. Interestingly and importantly, our data suggest that the expression of the active form of Rag GTPase heterodimers helps in reducing the accumulation of autophagosomes in CPZ-treated cells, further suggesting a major contribution of the Rag GTPase-mTORC1-TFEB signaling axis in CPZ-induced autophagic impairment.

2.
mBio ; 14(5): e0033223, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650650

RESUMO

IMPORTANCE: Interferon (IFN) regulatory factor (IRF3) is one of the key factors for type I IFN transcription. To sophisticatedly regulate type I IFN antiviral immune response, IRF3 activity is closely controlled by a variety of post-translational modifications. However, the regulatory mechanisms are still not fully elucidated. In the present study, we found that human deubiquitinase OTUD6B positively regulates IRF3-mediated antiviral immune response. OTUD6B can stabilize the IRF3 protein level via hydrolyzing (Lys33)-linked polyubiquitin at Lys315. More importantly, mice with OTUD6B overexpression exhibited more resistance to RNA virus infection. Thus, unlike the previous report that zebrafish OTUD6B negatively regulates the antiviral response by suppressing K63-linked ubiquitination of IRF3 and IRF7, we demonstrate that human OTUD6B actually enhances type I IFN response and has the potential for antiviral therapy.


Assuntos
Interferon Tipo I , Peixe-Zebra , Humanos , Animais , Camundongos , Imunidade Inata/genética , Interferon Tipo I/metabolismo , Fator Regulador 3 de Interferon/genética , Ubiquitinação
3.
Immunol Cell Biol ; 101(8): 735-745, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37253434

RESUMO

Coxsackievirus B3 (CVB3)-induced viral myocarditis (VMC) is characterized by immune cell infiltration and myocardial damage. High mobility group box 1 (HMGB1) is a highly conserved nuclear DNA-binding protein that participates in DNA replication, transcriptional regulation, repair response and inflammatory response in different disease models. To investigate the exact function of HMGB1 in CVB3-induced VMC, we crossed Hmgb1-floxed (Hmgb1f/f ) mice with mice carrying a suitable Cre recombinase transgenic strain to achieve conditional inactivation of the Hmgb1 gene in a cardiomyocyte-specific manner and to establish myocarditis. In this study, we found that cardiomyocyte-specific Hmgb1-deficient (Hmgb1f/f TgCre/+ ) mice exhibited exacerbated myocardial injury. Hmgb1-deficient cardiomyocytes may promote early apoptosis via the p53-mediated Bax mitochondrial pathway, as evidenced by the higher localization of p53 protein in the cytosol of Hmgb1-deficient cardiomyocytes upon CVB3 infection. Moreover, cardiomyocyte Hmgb1-deficient mice are more susceptible to cardiac dysfunction after infection. This study provides new insights into HMGB1 in VMC pathogenesis and a strategy for appropriate blocking of HMGB1 in the clinical treatment of VMC.


Assuntos
Infecções por Coxsackievirus , Enterovirus Humano B , Proteína HMGB1 , Miocardite , Animais , Camundongos , Apoptose/genética , Proteína HMGB1/metabolismo , Camundongos Endogâmicos BALB C , Miocardite/imunologia , Miocardite/patologia , Miocardite/virologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteína Supressora de Tumor p53/metabolismo , Infecções por Coxsackievirus/imunologia
4.
Front Microbiol ; 13: 1042414, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504817

RESUMO

Merozoite invasion of the erythrocytes in humans is a key step in the pathogenesis of malaria. The proteins involved in the merozoite invasion could be potential targets for the development of malaria vaccines. Novel viral-vector-based malaria vaccine regimens developed are currently under clinical trials. Vesicular stomatitis virus (VSV) is a single-stranded negative-strand RNA virus widely used as a vector for virus or cancer vaccines. Whether the VSV-based malarial vaccine is more effective than conventional vaccines based on proteins involved in parasitic invasion is still unclear. In this study, we have used the reverse genetics system to construct recombinant VSVs (rVSVs) expressing apical membrane protein 1 (AMA1), rhoptry neck protein 2 (RON2), and reticulocyte-binding protein homolog 5 (RH5), which are required for Plasmodium falciparum invasion. Our results showed that VSV-based viral vaccines significantly increased Plasmodium-specific IgG levels and lymphocyte proliferation. Also, VSV-PyAMA1 and VSV-PyRON2sp prime-boost regimens could significantly increase the levels of IL-2 and IFN-γ-producing by CD4+ and CD8+ T cells and suppress invasion in vitro. The rVSV prime-protein boost regimen significantly increase Plasmodium antigen-specific IgG levels in the serum of mice compared to the homologous rVSV prime-boost. Furthermore, the protective efficacy of rVSV prime protein boost immunization in the mice challenged with P. yoelii 17XL was better compared to traditional antigen immunization. Together, our results show that VSV vector is a novel strategy for malarial vaccine development and preventing the parasitic diseases.

5.
Front Cell Infect Microbiol ; 12: 1014897, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439208

RESUMO

Rv0790c is predicted to be a conserved hypothetical protein encoded by Mycobacterium tuberculosis (Mtb). However, its function in Mtb infection remains largely unknown. In this study, we found that Rv0790c promoted bacillary survival of M. smegmatis (Ms), both in vitro and in vivo. The bacillary burden of Ms exogenously expressing Rv0790c increased, whereas in Rv0790c-knockouts the bacillary burden decreased in infected macrophages. Multiple cellular processes were analyzed to explore the underlying mechanisms. We found that neither inflammatory regulation nor apoptotic induction were responsible for the promotion of bacillary survival mediated by Rv0790c. Interestingly, we found that Rv0790c facilitates mycobacterial survival through cellular autophagy at its early stage. Immunoprecipitation assay of autophagy initiation-related proteins indicated that Rv0790c interacted with mTOR and enhanced its activity, as evidenced by the increased phosphorylation level of mTOR downstream substrates, ULK-1, at Ser757 and P70S6K, at Thr389. Our study uncovers a novel autophagy suppressor encoded by mycobacterial Rv0790c, which inhibits the early stage of cellular autophagy induction upon Mtb infection and takes an important role in maintaining intracellular mycobacterial survival. It may aid in understanding the mechanism of Mtb evasion of host cellular degradation, as well as hold the potential to develop new targets for the prevention and treatment of tuberculosis.


Assuntos
Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Humanos , Mycobacterium tuberculosis/metabolismo , Autofagia/fisiologia , Macrófagos/microbiologia , Serina-Treonina Quinases TOR/metabolismo
6.
Biomed Res Int ; 2022: 5249576, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147635

RESUMO

Background: With the development of research, the importance of microRNAs (miRNAs) in the occurrence, metastasis, and prognosis of lung adenocarcinoma (LUAD) has attracted extensive attention. This study is aimed at predicting overall survival (OS) results through bioinformatics to identify novel miRNA biomarkers and hub genes. Materials and Methods: The data of LUAD-related miRNA and mRNA samples was downloaded from The Cancer Genome Atlas (TCGA) database. Upon screening and pretreatment of initial data, TCGA data were analyzed using R platform and a series of analytical tools to identify biomarkers with high specificity and sensitivity. Results: 7 miRNAs and 13 hub genes that had strong relation to the overall surviving status were identified in patients with LUAD. The expression of seven miRNAs (hsa-miR-19a-3p, hsa-miR-126-5p, hsa-miR-556-3p, hsa-miR-671-5p, hsa-miR-937-3p, hsa-miR-4664-3p, and hsa-miR-4746-5p) could apparently improve the OS rate of patient with LUAD. The 13 hub genes, namely, CCT6A, CDK5R1, CEP55, DNAJB4, EGLN3, HDGF, HOXC8, LIMD1, MKI67, PCP4L1, PPIL1, SCAI, and STK32A, showed a correlation with the OS status. Conclusion: 7 miRNAs were identified as novel biomarkers for the prognosis of patients with LUAD. This study offered a deeper comprehension of LUAD treatment and prognosis from the molecular level and helped enhance the understanding of the pathogenesis and potential molecular events of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Adenocarcinoma de Pulmão/patologia , Biomarcadores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular , Chaperonina com TCP-1 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas com Domínio LIM , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , RNA Mensageiro
7.
PLoS One ; 17(3): e0264645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35290415

RESUMO

As explorations deepen, the role of microRNAs (miRNAs) in lung squamous cell carcinoma (LUSC), from its emergence to metastasis and prognosis, has elicited extensive concern. LUSC-related miRNA and mRNA samples were acquired from The Cancer Genome Atlas (TCGA) database. The data were initially screened and pretreated, and the R platform and series analytical tools were used to identify the specific and sensitive biomarkers. Seven miRNAs and 15 hub genes were found to be closely related to the overall survival of patients with LUSC. Determination of the expression of these miRNAs can help improve the overall survival of LUSC patients. The 15 hub genes correlated with overall survival (OS). The new miRNA markers were identified to predict the prognosis of LUSC. The findings of this study offer novel views on the evolution of precise cancer treatment approaches with high reliability.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroRNAs/genética , Prognóstico , Reprodutibilidade dos Testes
8.
Front Pharmacol ; 13: 806995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153782

RESUMO

Background: Lung squamous cell carcinoma (LUSC) has been a highly malignant tumor with very poor prognosis. It is confirmed that pyroptosis refers to the deaths of cells in a programmed and inflammatory manner. Nevertheless, the correlation between expression of genes related with pyroptosis and their prognosis remains uncertain in LUSC. Methods: Utilization of The Cancer Genome Atlas (TCGA) cohort has been done for evaluating the prognostics of pyroptosis-related genes for survival and constructing a signature with multiple genes. The least absolute shrinkage and selection operator (LASSO) Cox regression was performed for establishing such pyroptosis-related gene signature. Results: Eventually, identification of 28 genes in relation to pyroptosis was made in LUSC and healthy lung tissues. Upon the basis of these differentially-expressed genes (DEGs), the patients of LUSC can be divided into two subtypes. Nine gene signatures were established using LASSO. The surviving rate for low-risk group was apparently greater in contrast with the high-risk group (p < .001). According to our finding, risk score worked as an independent predictive factor of OS among LUSC sufferers in combination with clinical characteristics. In line with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, the enrichment of immunity-related genes and decreasing immunity status among the high-risk group. Conclusion: Genes in relation with pyroptosis played an essential role in tumor immunity, which is capable of predicting the prognosis for LUSCs.

9.
Transl Oncol ; 14(12): 101221, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34530193

RESUMO

In cancer, the extracellular matrix is extensively remodeled during chronic inflammation, thus affecting cell transcription, differentiation, migration and cell-cell interactions. Matrix metalloproteinases can degrade the extracellular matrix of tumor tissues and take important roles in disease progression. Numerous efforts to develop cancer treatments targeting matrix metalloproteinases have failed in clinical trials owing to the ineffectiveness and toxicity of the applied inhibitors. In this study, we investigated the potential of targeting matrix metalloproteinases and oncolytic virus combination in cancer therapy. We found that MMP3 expression was upregulated in various cancers and MMP3 expression in the tumor cells, but not in other tissues, was important for tumor growth and metastasis. Single treatment of colon cancer with multiple MMP3 inhibitors was not effective in mice. Nevertheless, the therapeutic effect of MMP3 was greatly improved by combination with an oncolytic virus. A potential mechanism of MMP3 in regulating tumor cell proliferation and invasion was mediated via Erk1/2 an NF-κB signaling. This study reveals that MMP3 is a promising target and the combined treatment with oncolytic virus is a potential strategy for cancer therapy.

10.
J Immunol ; 205(11): 3167-3178, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127822

RESUMO

Deubiquitinating enzymes (DUBs) are cysteine proteases that reverse the ubiquitination by removing ubiquitins from the target protein. The human genome encodes ∼100 potential DUBs, which can be classified into six families, influencing multiple cellular processes, such as antiviral responses, inflammatory responses, apoptosis, etc. To systematically explore the role of DUBs involved in antiviral immunity, we performed an RNA interference-based screening that contains 97 human DUBs. We identified that ubiquitin-specific protease (USP) 39 expression modulates the antiviral activity, which is, to our knowledge, a previously unknown function of this enzyme. Small interfering RNA knockdown of USP39 significantly enhanced viral replication, whereas overexpression of USP39 had an opposite effect. Mechanistically, USP39 does not affect the production of type I IFN but significantly promotes JAK/STAT downstream of type I signaling by enhancing IFN-stimulated response elements promoter activity and expression of IFN-stimulated genes. Interestingly, USP39, previously considered not to have the deubiquitinase activity, in this study is proved to interact with STAT1 and sustain its protein level by deubiqutination. Furthermore, we found that through novel mechanism USP39 can significantly decrease K6-linked but not K48-linked ubiquitination of STAT1 for degradation. Taken together, these findings uncover that USP39 is, to our knowledge, a new deubiquitinase that positively regulates IFN-induced antiviral efficacy.


Assuntos
Antivirais/metabolismo , Interferon Tipo I/metabolismo , Fator de Transcrição STAT1/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular , Feminino , Células HEK293 , Humanos , Camundongos , Interferência de RNA/fisiologia , Transdução de Sinais/fisiologia , Ubiquitinação/fisiologia , Ubiquitinas/metabolismo
11.
Mol Immunol ; 127: 47-55, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32927163

RESUMO

Mycobacterium tuberculosis (Mtb) is an intracellular pathogen that can infect and replicate in macrophages. Peptidoglycan (PGN) is a major component of the mycobacterial cell wall and is recognized by host pattern recognition receptors (PRRs). Many bacteria modulate and evade the immune defenses of their hosts through PGN deacetylation. Rv1096 was previously characterized as a PGN N-deacetylase gene in Mtb. However, the underlying mechanism by which Rv1096 regulates host immune defenses during macrophage infection remains unclear. In the present study, we investigated the role of Rv1096 in evading host immunity using a recombinant M. smegmatis expressing exogenous Rv1096 and Rv1096-deleted Mtb strain H37Rv mutant. We found that Rv1096 promoted intracellular bacillary survival and inhibited the inflammatory response in M. smegmatis- or Mtb-infected macrophages. The inhibition of mycobacteria-induced inflammatory response in macrophages was at least partially due to NF-κB and MAPK activation downstream of TLR and NOD signaling pathways. Furthermore, we found that Rv1096 inhibitory effect on inflammatory response was associated with TLR2, TLR4 and NOD2. Finally, we demonstrated the PGN deacetylase activity of Rv1096 by Fourier transform IR and Rv1096 NODB deficient mutant. Our findings suggest that Rv1096 may deacetylate PGNs to evade PRRs recognition, thus protecting Mtb from host immune surveillance and clearance in macrophages.


Assuntos
Amidoidrolases/metabolismo , Proteínas de Bactérias/metabolismo , Sistema de Sinalização das MAP Quinases , Viabilidade Microbiana , Mycobacterium smegmatis/citologia , Mycobacterium tuberculosis/enzimologia , NF-kappa B/metabolismo , Peptidoglicano/metabolismo , Animais , Proteínas de Bactérias/química , Citocinas/metabolismo , Feminino , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium smegmatis/crescimento & desenvolvimento , Mycobacterium tuberculosis/crescimento & desenvolvimento , Domínios Proteicos , Células RAW 264.7
12.
Tuberculosis (Edinb) ; 120: 101900, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32090861

RESUMO

Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis (Mtb). It leads to approximately 1 million deaths annually. Receptor expressed in lymphoid tissues-like protein 1 (RELL1) is a homologous binding partner of receptor expressed in lymphoid tissues (RELT), member of the human tumor necrosis factor receptor family. Genome-wide analysis screening revealed that downregulation of RELL1 in macrophages notably reduces Mtb survival within macrophages. However, the underlying mechanism is not clear. Here, we show that RELL1 expression in macrophages significantly decreased upon Mtb infection. Mtb survival increased in RAW264.7 cells with upregulated RELL1 expression. However, the proinflammatory cytokines TNF-α and IL-6 responsible for Mtb clearance were increased. Further, RELL 1 enhanced mTOR activity and inhibited autophagy through direct interaction. Hence, the reduced autophagy may antagonize increased inflammation in RELL1 upregulated macrophages and promote Mtb survival in macrophages. Together, our results suggest that the reduction of RELL1 expression upon Mtb infection may enhance autophagy and facilitate bacterial clearance, providing a new target for Mtb treatment.


Assuntos
Autofagia , Macrófagos/microbiologia , Mycobacterium tuberculosis/patogenicidade , Tuberculose/microbiologia , Animais , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Células RAW 264.7 , Transdução de Sinais , Tuberculose/genética , Tuberculose/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
13.
Microbes Infect ; 22(1): 46-54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31319178

RESUMO

Calpains are calcium-activated neutral cysteine proteases. The dysregulation of calpain activity has been found to be related to cardiovascular diseases, for which calpain inhibition is used as a treatment. Viral myocarditis (VMC) is primarily caused by Coxsackievirus group B3 virus infection (CVB3). CVB3 virus infection induces autophagy and hijacks this process to facilitate its replication. In this study, we found that calpain was significantly activated in hearts affected by VMC. However, pharmacologically inhibiting calpain aggravated VMC symptoms in mice due to myocardial inflammation and cardiac dysfunction. The inhibition of calpain activity in vitro led to the accumulation of LC3-II and increased levels of p62/SQSTM1 protein expression, suggesting that autophagic flux was impaired by calpain inhibition. These effects of calpain inhibition were also observed in capn4-specific myocardial knockout mice in vivo. Furthermore, our results provided evidence that calpain inhibition in VMC, unlike other cardiovascular diseases, exacerbated the disease symptom by impairing CVB3-induced autophagic flux, which may subsequently reduce virus autolysosome degradation. Our findings indicated that calpain inhibition may not be a good treatment for VMC disease in a clinical setting.


Assuntos
Autofagia , Calpaína/metabolismo , Infecções por Coxsackievirus/virologia , Enterovirus Humano B/fisiologia , Miocardite/virologia , Animais , Autofagossomos/metabolismo , Calpaína/antagonistas & inibidores , Calpaína/deficiência , Infecções por Coxsackievirus/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocardite/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/virologia , Replicação Viral
15.
Tuberculosis (Edinb) ; 116: 22-31, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31153514

RESUMO

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis (Mtb), leading to about a million deaths each year. EspR is a DNA binding protein of Mtb which regulates expression of multiple genes and the activity of ESX-1 secretion system of the bacteria, with itself being secreted out as a substrate of ESX-1. We explored the function of secreted EspR in host cells by overexpressing the protein in murine macrophage cell line RAW264.7, infecting the cells with BCG which does not secrete EspR, and evaluating the antimicrobial responses of the cells. We found that EspR resulted in an increased intracellular bacteria load in macrophages. This is due to its inhibition on BCG induced expression of inflammatory cytokines and inducible nitric oxide synthase (iNOS), as well as host cell apoptosis. Mechanism study showed that EspR directly interacted with adaptor protein myeloid differentiation factor 88 (MyD88), suppressed MyD88 dependent Toll-like receptor (TLR) and IL-1R signal activation, thus reduced inflammatory responses and apoptosis in macrophages and promoted mycobacteria survival.


Assuntos
Apoptose , Proteínas de Bactérias/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/microbiologia , Macrófagos/microbiologia , Mycobacterium tuberculosis/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Animais , Antígenos de Bactérias/metabolismo , Carga Bacteriana , Proteínas de Bactérias/genética , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Viabilidade Microbiana , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Fator 88 de Diferenciação Mieloide/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais
16.
Nat Microbiol ; 4(11): 1872-1884, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30988430

RESUMO

Outbreaks of viral infections are a global health burden. Although type I interferon (IFN-I) exerts broad-spectrum antiviral effects, its antiviral efficacy in host cells is largely restricted by viruses. How the antiviral efficacy of IFN-I can be improved remains to be explored. Here, we identified the ADP-ribosyltransferase poly(ADP-ribose) polymerase family member 11 (PARP11) as a potent regulator of IFN-I antiviral efficacy. PARP11 does not restrict IFN-I production induced by vesicular stomatitis virus or Sendai virus but inhibits the strength of IFN-I-activated signalling. Mechanistically, PARP11 mono-ADP-ribosylates the ubiquitin E3 ligase ß-transducin repeat-containing protein (ß-TrCP). Mono-ADP-ribosylation of ß-TrCP promotes IFNα/ß receptor subunit 1 (IFNAR1) ubiquitination and degradation. Moreover, PARP11 expression is upregulated by virus infections, including vesicular stomatitis virus, herpes simplex virus-1 and influenza A virus, thus promoting ADP-ribosylation-mediated viral evasion. We further highlight the potential for repurposing clinical ADP-ribosylation inhibitors. We found that rucaparib can target PARP11 to stabilize IFNAR1 and therefore exhibits efficient enhancement of IFN-I signalling and the host antiviral response. Consequently, rucaparib renders mice more resistant to viral infection. Our study updates the understanding of how ß-TrCP regulates its substrates and may provide a druggable target for improving IFN antiviral efficacy.


Assuntos
Interferon Tipo I/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Receptor de Interferon alfa e beta/química , Receptor de Interferon alfa e beta/metabolismo , Viroses/imunologia , Proteínas Contendo Repetições de beta-Transducina/metabolismo , ADP-Ribosilação , Animais , Células Cultivadas , Chlorocebus aethiops , Modelos Animais de Doenças , Células HEK293 , Células Hep G2 , Humanos , Indóis/administração & dosagem , Indóis/farmacologia , Camundongos , Proteólise , Vírus Sendai/imunologia , Transdução de Sinais , Ubiquitinação , Células Vero , Vesiculovirus/imunologia , Viroses/tratamento farmacológico , Viroses/metabolismo
17.
Biochem Biophys Res Commun ; 504(4): 734-741, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30217446

RESUMO

Macrophage activation plays a critical role in the innate immune response. Ornithine decarboxylase (ODC1) metabolizes l-ornithine to polyamines and is the rate-limiting enzyme involved in the metabolism of polyamines, which are reportedly involved in cell differentiation, proliferation, and migration. However, the function of ODC1 in immune cells and especially in macrophages, as well as its underlying molecular mechanism, remains unclear. This study revealed the potential ODC1 function and mechanism associated with the lipopolysaccharide (LPS)-, Bacillus Calmette-Guerin (BCG)-, or carbon tetrachloride (CCl4)-induced inflammatory response in macrophages. We found significant upregulation of ODC1 in macrophages following LPS simulation and ODC1-specific suppression of proinflammatory cytokine secretion from macrophages upon stimulation with LPS, BCG and CCl4, respectively, suggesting a role as a common control element of the inflammatory response. Western blotting for nuclear factor-κB and mitogen-activated protein kinases revealed significant inhibition of phosphorylation of multiple transcription factors following ODC1 overexpression in macrophages. Moreover, ODC1 inhibited reactive oxygen species-induced and caspase-dependent apoptosis highlighted by decreased caspase-3 and -9 expression following ODC1 upregulation. These findings indicated that ODC1 was involved in attenuating the inflammatory response upon stimulation of macrophages, making it a potential therapeutic target for inflammatory diseases.


Assuntos
Apoptose , Inflamação/metabolismo , Macrófagos/metabolismo , Ornitina Descarboxilase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação/enzimologia , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Ornitina Descarboxilase/genética , Fosforilação , Células RAW 264.7 , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
J Mol Cell Cardiol ; 114: 48-57, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29108785

RESUMO

Semaphorin7A (Sema7A) has been reported to play various roles in nerve axon growth, tumor suppression, and tissue remodeling, as well as regulation of intestinal inflammation diseases. Viral myocarditis (VMC) characterized by viral-myocardial-cell necrosis and inflammatory cell infiltration is a common clinical disease of the cardiovascular system. However, the role of Sema7A in coxsackievirus B3 (CVB3)-induced VMC has not been reported. In this study, we generated an acute VMC mouse model by CVB3 infection, and manipulated Sema7A expression by in vivo polyethyleneimine-mediated Sema7A down-regulation. Our results indicated that Sema7A was up-regulated in cardiomyocytes during VMC, and that Sema7A down-regulation following short hairpin RNA interference or mAb neutralization effectively protected mice from VMC. Additionally, reduced inflammatory responses were observed along with Sema7A down-regulation. Furthermore, adoptive transfer of α1ß1-integrin macrophages exacerbated CVB3-induced myocarditis, suggesting the significance of α1ß1-integrin macrophages in response to VMC. We observed that co-culture of neonatal myocardiocytes with macrophages increased the percentage of α1ß1-integrin macrophages, while Sema7A neutralization reduced α1ß1-integrin macrophages in heart tissue of VMC mice. These results demonstrated that Sema7A, as an inflammation regulator in CVB3-induced VMC, might interact with α1ß1-integrin in macrophages to enhance the inflammatory response and aggravate disease severity. Our findings provided insight into the potential role of Sema7A as a therapeutic treatment for VMC.


Assuntos
Antígenos CD/metabolismo , Enterovirus Humano B/fisiologia , Inflamação/patologia , Integrina alfa1beta1/metabolismo , Macrófagos/metabolismo , Miocardite/metabolismo , Miocardite/virologia , Semaforinas/metabolismo , Transferência Adotiva , Animais , Animais Recém-Nascidos , Citocinas/metabolismo , Regulação para Baixo , Células HEK293 , Células HeLa , Humanos , Inflamação/genética , Mediadores da Inflamação/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Miocardite/genética , Miocardite/patologia , Regulação para Cima
19.
Artigo em Inglês | MEDLINE | ID: mdl-28642849

RESUMO

The recurrent Coxsackievirus B3 (CVB3) infection is the most important cause of intractable myocarditis which often leads to chronic myocarditis and even dilated cardiomyopathy. Therefore, enhanced DNA vaccines capable of memory CD8 T cells are essential for long-lasting immunological protection against CVB3 infection. In this study, absent in melanoma 2 (AIM2) was used as an adjuvant to enhance the induction of memory CD8 T cells elicited by VP1 (viral capsid protein 1) vaccine. Mice were intramuscularly injected with 50 µg AIM2 plasmid and equal amount of VP1 plasmid (pAIM2/pVP1) vaccine 4 times at 2 week-intervals. We observed that the protection of pAIM2/pVP1 vaccine against CVB3 challenge was evidenced by significantly improved cardiac function, reduced myocardial injuries, and increased survival rate when compared with immunization with pVP1. Co-immunization with pAIM2/pVP1 robustly augmented T lymphocytes proliferation and CVB3-specific cytotoxic T lymphocyte responses. Importantly, 16 weeks after the last immunization, pAIM2/pVP1 co-immunization significantly enhanced the expression of Bcl-6, SOCS3, and Sca-1 which are critical for memory CD8 T cells as compared with pVP1 immunization. Notably, CD8 T cells that are likely vaccine-induced memory T cells were responsible for the protective efficacy of pAIM2/pVP1 vaccine by abolition of a CD8 T cell immune response following a lethal dose of CVB3 infection. Our results indicate that AIM2-adjuvanted vaccine could be a potential and promising approach to promote a long-lasting protection against CVB3-induced myocarditis.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Proteínas do Capsídeo/imunologia , Infecções por Coxsackievirus/prevenção & controle , Proteínas de Ligação a DNA/imunologia , Enterovirus Humano B/imunologia , Imunização , Vacinas de DNA/imunologia , Adjuvantes Imunológicos , Animais , Antígenos Ly/metabolismo , Proteínas do Capsídeo/genética , Proliferação de Células , Infecções por Coxsackievirus/imunologia , Proteínas de Ligação a DNA/administração & dosagem , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Células HeLa , Traumatismos Cardíacos/patologia , Humanos , Injeções Intramusculares , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Miocardite/imunologia , Miocardite/prevenção & controle , Miocardite/virologia , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Taxa de Sobrevida , Vacinas de DNA/administração & dosagem , Vacinas Virais/imunologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-28224119

RESUMO

Tuberculosis (TB) remains a serious health problem worldwide, and an urgent need exists to improve or replace the available vaccine, Mycobacterium bovis bacillus Calmette-Guérin (BCG). Most vaccination protocols adapt two or three doses to induce long-term lasting immunity. Our previous study showed that the naked DNA encoding the triple-antigen fusion TFP846 (Rv3615c-Mtb10.4-Rv2660c) induced robust T cellular immune responses accompanying four inoculations against mycobacteria infection. However, a number of compliance issues exist in some areas lacking the appropriate medical infrastructure with multiple administrations. In this study, a novel vesicular stomatitis virus expressing TFP846 (VSV-846) was developed and the immune responses elicited by VSV-846 were evaluated. We observed that intranasal delivery of VSV-846 induced a potent antigen-specific T cell response following a single dose and VSV-846 efficiently controlled bacterial growth to levels ~10-fold lower than that observed in the mock group 6 weeks post-infection in BCG-infected mice. Importantly, mice immunized with VSV-846 provided long-term protection against mycobacteria infection compared with those receiving p846 or BCG immunization. Increased memory T cells were also observed in the spleens of VSV-846-vaccinated mice, which could be a potential mechanism associated with long-term protective immune response. These findings supported the use of VSV as an antigen delivery vector with the potential for TB vaccine development.


Assuntos
Administração Intranasal , Vacina BCG/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Vesiculovirus , Vacinas Virais/imunologia , Animais , Antígenos de Bactérias/imunologia , Antígenos Virais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Escherichia coli/genética , Feminino , Imunidade Celular , Interferon gama , Pulmão/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis/genética , Mycobacterium tuberculosis/imunologia , Baço , Tuberculose/imunologia , Vacinação , Vacinas Sintéticas/imunologia , Proteínas Virais de Fusão , Vacinas Virais/genética
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