Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.993
Filtrar
1.
Nat Commun ; 11(1): 4979, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020468

RESUMO

Cellular senescence is a known driver of carcinogenesis and age-related diseases, yet senescence is required for various physiological processes. However, the mechanisms and factors that control the negative effects of senescence while retaining its benefits are still elusive. Here, we show that the rasGAP SH3-binding protein 1 (G3BP1) is required for the activation of the senescent-associated secretory phenotype (SASP). During senescence, G3BP1 achieves this effect by promoting the association of the cyclic GMP-AMP synthase (cGAS) with cytosolic chromatin fragments. In turn, G3BP1, through cGAS, activates the NF-κB and STAT3 pathways, promoting SASP expression and secretion. G3BP1 depletion or pharmacological inhibition impairs the cGAS-pathway preventing the expression of SASP factors without affecting cell commitment to senescence. These SASPless senescent cells impair senescence-mediated growth of cancer cells in vitro and tumor growth in vivo. Our data reveal that G3BP1 is required for SASP expression and that SASP secretion is a primary mediator of senescence-associated tumor growth.


Assuntos
Senescência Celular/fisiologia , DNA Helicases/metabolismo , Neoplasias/patologia , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Células A549 , Animais , Carcinogênese , Linhagem Celular , Movimento Celular , Citocinas/metabolismo , DNA Helicases/antagonistas & inibidores , DNA Helicases/deficiência , Humanos , Inflamação , Camundongos , Neoplasias/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/deficiência , RNA Helicases/antagonistas & inibidores , RNA Helicases/deficiência , Proteínas com Motivo de Reconhecimento de RNA/antagonistas & inibidores , Proteínas com Motivo de Reconhecimento de RNA/deficiência , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
2.
PLoS Pathog ; 16(9): e1008767, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903273

RESUMO

Many viruses target signal transducer and activator of transcription (STAT) 1 to antagonise antiviral interferon signalling, but targeting of STAT3, a pleiotropic molecule that mediates signalling by diverse cytokines, is poorly understood. Here, using lyssavirus infection, quantitative live cell imaging, innate immune signalling and protein interaction assays, and complementation/depletion of STAT expression, we show that STAT3 antagonism is conserved among P-proteins of diverse pathogenic lyssaviruses and correlates with pathogenesis. Importantly, P-protein targeting of STAT3 involves a highly selective mechanism whereby P-protein antagonises cytokine-activated STAT3-STAT1 heterodimers, but not STAT3 homodimers. RT-qPCR and reporter gene assays indicate that this results in specific modulation of interleukin-6-dependent pathways, effecting differential antagonism of target genes. These data provide novel insights into mechanisms by which viruses can modulate cellular function to support infection through discriminatory targeting of immune signalling complexes. The findings also highlight the potential application of selective interferon-antagonists as tools to delineate signalling by particular STAT complexes, significant not only to pathogen-host interactions but also cell physiology, development and cancer.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica , Lyssavirus/imunologia , Infecções por Rhabdoviridae/imunologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteínas Virais/metabolismo , Células HEK293 , Células HeLa , Humanos , Interleucina-6/metabolismo , Infecções por Rhabdoviridae/metabolismo , Infecções por Rhabdoviridae/virologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT3/genética , Transativadores , Proteínas Virais/genética
3.
Zhonghua Bing Li Xue Za Zhi ; 49(10): 999-1002, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-32992412

RESUMO

Objective: To study the expression of phosphates signal transducer and activator of transcription 3 (pSTAT3) and programmed death ligand-1 (PD-L1) in extranodal NK/T cell lymphomas (ENKTCL) and the relationships of pSTAT3 and PD-L1 expression with the clinicopathological characteristics and prognosis of ENKTCL. Methods: Fifty-one cases of ENKTCL diagnosed at Guangdong Provincial People's Hospital from June 2015 to February 2019 were included in the study. The expression of pSTAT3 and PD-L1 was examined using immunohistochemistry. Results: There were 35 males and 16 females, ranging from 18 to 85 years old with a median age of 47 years. The positive rates of pSTAT3 and PD-L1 expression were 68.6% (35/51) and 76.5% (39/51), respectively. pSTAT3 expression was correlated with PD-L1 expression (P=0.033,R=0.322), while there were no associations of pSTAT3 and PD-L1 expression with the clinicopathological characteristics of ENKTCL, including age, sex, clinical site, B symptom, Ann Arbor stage, LDH value, EBV DNA load of peripheral blood and international proliferation index score. Kaplan-Meier survival analysis showed the prognoses of the pSTAT3 and PD-L1 positive groups were slightly better than the respective negative groups, but the differences were not significantly (P>0.05). Conclusions: pSTAT3 is highly expressed in extranodal NK/T cell lymphoma and related to the expression of PD-L1, which provides a potential target and rationale for combinations of targeted therapies and immune checkpoint blockade inhibitors in the treatment of ENKTCL.


Assuntos
Antígeno B7-H1/metabolismo , Linfoma Extranodal de Células T-NK , Fator de Transcrição STAT3/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos , Prognóstico , Adulto Jovem
4.
Nat Commun ; 11(1): 4512, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908147

RESUMO

Hydrogen peroxide (H2O2) is recognized to act as a signaling molecule. Peroxiredoxins (Prxs) have the ability to transfer H2O2-derived oxidizing equivalents to redox-regulated target proteins, thus facilitating the transmission of H2O2 signals. It has remained unclear how Prxs and their target proteins are brought together to allow for target-specific protein thiol oxidation. Addressing the specific case of Prx2-dependent STAT3 oxidation, we here show that the association of the two proteins occurs prior to Prx oxidation and depends on a scaffolding protein, the membrane chaperone annexin A2. Deletion or depletion of annexin A2 interrupts the transfer of oxidizing equivalents from Prx2 to STAT3, which is observed to take place on membranes. These findings support the notion that the Prx2-STAT3 redox relay is part of a highly organized membrane signaling domain.


Assuntos
Anexina A2/metabolismo , Peroxirredoxinas/metabolismo , Fator de Transcrição STAT3/metabolismo , Anexina A2/genética , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Dissulfetos/metabolismo , Células HEK293 , Humanos , Peróxido de Hidrogênio/metabolismo , Oxirredução , Ligação Proteica , Domínios Proteicos , Transdução de Sinais
5.
Nat Commun ; 11(1): 4116, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807793

RESUMO

Glioblastoma contains a rare population of self-renewing brain tumor stem cells (BTSCs) which are endowed with properties to proliferate, spur the growth of new tumors, and at the same time, evade ionizing radiation (IR) and chemotherapy. However, the drivers of BTSC resistance to therapy remain unknown. The cytokine receptor for oncostatin M (OSMR) regulates BTSC proliferation and glioblastoma tumorigenesis. Here, we report our discovery of a mitochondrial OSMR that confers resistance to IR via regulation of oxidative phosphorylation, independent of its role in cell proliferation. Mechanistically, OSMR is targeted to the mitochondrial matrix via the presequence translocase-associated motor complex components, mtHSP70 and TIM44. OSMR interacts with NADH ubiquinone oxidoreductase 1/2 (NDUFS1/2) of complex I and promotes mitochondrial respiration. Deletion of OSMR impairs spare respiratory capacity, increases reactive oxygen species, and sensitizes BTSCs to IR-induced cell death. Importantly, suppression of OSMR improves glioblastoma response to IR and prolongs lifespan.


Assuntos
Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Radiação Ionizante , Receptores de Oncostatina M/metabolismo , Animais , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Masculino , Camundongos , Camundongos SCID , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Oncostatina M/metabolismo , Estresse Oxidativo/efeitos da radiação , Receptores de Oncostatina M/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos da radiação
6.
Nat Commun ; 11(1): 4115, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807795

RESUMO

The transcription factor STAT3 is frequently activated in human solid and hematological malignancies and remains a challenging therapeutic target with no approved drugs to date. Here, we develop synthetic antibody mimetics, termed monobodies, to interfere with STAT3 signaling. These monobodies are highly selective for STAT3 and bind with nanomolar affinity to the N-terminal and coiled-coil domains. Interactome analysis detects no significant binding to other STATs or additional off-target proteins, confirming their exquisite specificity. Intracellular expression of monobodies fused to VHL, an E3 ubiquitin ligase substrate receptor, results in degradation of endogenous STAT3. The crystal structure of STAT3 in complex with monobody MS3-6 reveals bending of the coiled-coil domain, resulting in diminished DNA binding and nuclear translocation. MS3-6 expression strongly inhibits STAT3-dependent transcriptional activation and disrupts STAT3 interaction with the IL-22 receptor. Therefore, our study establishes innovative tools to interfere with STAT3 signaling by different molecular mechanisms.


Assuntos
Anticorpos/metabolismo , Fator de Transcrição STAT3/metabolismo , Células A549 , Anticorpos/genética , Western Blotting , Calorimetria , Cristalografia por Raios X , Citometria de Fluxo , Polarização de Fluorescência , Imunofluorescência , Humanos , Espectrometria de Massas , Ligação Proteica , Domínios Proteicos/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Biologia Sintética
7.
Nat Commun ; 11(1): 3816, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732870

RESUMO

Detection of microbial components such as lipopolysaccharide (LPS) by Toll-like receptor 4 (TLR4) on macrophages induces a robust pro-inflammatory response that is dependent on metabolic reprogramming. These innate metabolic changes have been compared to aerobic glycolysis in tumour cells. However, the mechanisms by which TLR4 activation leads to mitochondrial and glycolytic reprogramming are unknown. Here we show that TLR4 activation induces a signalling cascade recruiting TRAF6 and TBK-1, while TBK-1 phosphorylates STAT3 on S727. Using a genetically engineered mouse model incapable of undergoing STAT3 Ser727 phosphorylation, we show ex vivo and in vivo that STAT3 Ser727 phosphorylation is critical for LPS-induced glycolytic reprogramming, production of the central immune response metabolite succinate and inflammatory cytokine production in a model of LPS-induced inflammation. Our study identifies non-canonical STAT3 activation as the crucial signalling intermediary for TLR4-induced glycolysis, macrophage metabolic reprogramming and inflammation.


Assuntos
Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Expressão Gênica , Glicólise/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/genética , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição STAT3/genética , Serina/genética , Serina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 4 Toll-Like/genética
8.
Life Sci ; 258: 118158, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750435

RESUMO

AIMS: Glioblastoma multiforme (GBM) is characterized by aggressive infiltration and terrible lethality. The overwhelming majority of chemotherapeutic drugs fail to exhibit the desired treatment effects. Polydatin (PD), which was initially extracted from Polygonum cuspidatum, is distinguished for its outstanding cardioprotective, hepatoprotective, and renal protective effects, as well as significant anticancer activities. However, the anti-GBM effect of PD is unclear. MATERIALS AND METHODS: Cell proliferation and apoptosis after PD intervention were estimated using MTT, colony formation and flow cytometry assays in vitro, while wound-healing and Transwell assays were applied to assess cell migration and invasion. In addition, the anti-GBM effects of PD in vivo were detected in the subcutaneous tumor model of nude mice. Moreover, Western blot, immunofluorescence and immunohistochemical staining assays were employed to elaborate the relevant molecular mechanisms. KEY FINDINGS: The present study demonstrated that PD repressed cell proliferation, migration, invasion and stemness and promoted apoptosis in GBM cells. Moreover, by correlating the molecular characteristics of cancer cells with different sensitivities to PD and employing diverse analytical methods, we ultimately verified that the cytotoxicity of PD was related to EGFR-AKT/ERK1/2/STAT3-SOX2/Snail signaling pathway inhibition, in which multiple components were vital therapeutic targets of GBM. SIGNIFICANCE: This work demonstrated that PD could inhibit proliferation, migration, invasion and stemness and induce apoptosis by restraining multiple components of the EGFR-AKT/ERK1/2/STAT3-SOX2/Snail signaling pathway in GBM cells.


Assuntos
Antineoplásicos/uso terapêutico , Glioblastoma/tratamento farmacológico , Glucosídeos/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Estilbenos/uso terapêutico , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Glucosídeos/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Estilbenos/farmacologia
9.
Life Sci ; 258: 118217, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32768575

RESUMO

AIMS: Astrocytes expressing the aquaporin-4 (AQP4) water channel are pathogenic, disease specific immunoglobulins (IgG) found in neuromyelitis optica spectrum disorder (NMOSD), referred to as NMO-IgG, which targets astrocytic AQP4. The interleukin-6 (IL-6) signaling when astrocytes were exposed to NMO-IgG present in the serum of NMOSD patients was evaluated. MAIN METHODS: Serum or human-IgG from NMOSD or healthy controls were exposed to astrocytes. The selectivity and immuno-pathological consequences of Ig binding to surface epitopes were measured by confocal microscopy. Astrocytes were exposed to medium, IL-6, soluble IL-6 receptor (sIL-6R), IL-6 + sIL-6R (IL-6/R), NMO-IgG or control-IgG, NMO-IgG + IL-6/R. The expression of key proteins in IL-6 signaling pathway, IL-6 cytokine and mRNA levels were evaluated by western blotting, enzyme-linked immunosorbent assay and quantitative polymerase chain reaction, respectively. KEY FINDINGS: Serum or NMO-IgG from NMOSD patients both induced the rapid downregulation of AQP4 expression on the surface of astrocytes. Stimulation of astrocytes with NMO-IgG, IL-6/R, and NMO-IgG + IL-6/R resulted in the enhancement of IL-6 mRNA expression. Meanwhile, the exogenous addition of NMO-IgG elicited an inflammatory transcriptional response that involved signaling through the Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) pathway. Inhibition of the IL-6/JAK/STAT3 pathway with the JAK1/2 specific inhibitor, AZD1480, reversed the associated increase of IL-6. SIGNIFICANCE: Our findings suggest that NMO-IgG can stimulate the astrocytic JAK1/2/STAT3-dependent inflammatory response, which represents one of the important events in NMO pathogenesis. Inhibition of the JAK1/2 signaling pathway may be a novel promising therapy for NMOSD.


Assuntos
Astrócitos/metabolismo , Imunoglobulina G/sangue , Interleucina-6/metabolismo , Janus Quinases/metabolismo , Neuromielite Óptica/sangue , Fator de Transcrição STAT3/metabolismo , Adulto , Idoso , Animais , Astrócitos/efeitos dos fármacos , Autoanticorpos/sangue , Autoanticorpos/farmacologia , Células Cultivadas , Feminino , Humanos , Imunoglobulina G/farmacologia , Interleucina-6/agonistas , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Fator de Transcrição STAT3/agonistas , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 117(35): 21420-21431, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817494

RESUMO

One of the emerging hallmarks of cancer illustrates the importance of metabolic reprogramming, necessary to synthesize the building blocks required to fulfill the high demands of rapidly proliferating cells. However, the proliferation-independent instructive role of metabolic enzymes in tumor plasticity is still unclear. Here, we provide evidence that glutathione peroxidase 8 (GPX8), a poorly characterized enzyme that resides in the endoplasmic reticulum, is an essential regulator of tumor aggressiveness. We found that GPX8 expression was induced by the epithelial-mesenchymal transition (EMT) program. Moreover, in breast cancer patients, GPX8 expression significantly correlated with known mesenchymal markers and poor prognosis. Strikingly, GPX8 knockout in mesenchymal-like cells (MDA-MB-231) resulted in an epithelial-like morphology, down-regulation of EMT characteristics, and loss of cancer stemness features. In addition, GPX8 knockout significantly delayed tumor initiation and decreased its growth rate in mice. We found that these GPX8 loss-dependent phenotypes were accompanied by the repression of crucial autocrine factors, in particular, interleukin-6 (IL-6). In these cells, IL-6 bound to the soluble receptor (sIL6R), stimulating the JAK/STAT3 signaling pathway by IL-6 trans-signaling mechanisms, so promoting cancer aggressiveness. We observed that in GPX8 knockout cells, this signaling mechanism was impaired as sIL6R failed to activate the JAK/STAT3 signaling pathway. Altogether, we present the GPX8/IL-6/STAT3 axis as a metabolic-inflammatory pathway that acts as a robust regulator of cancer cell aggressiveness.


Assuntos
Neoplasias da Mama/enzimologia , Interleucina-6/metabolismo , Janus Quinases/metabolismo , Peroxidases/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fenótipo , Transdução de Sinais
11.
Int J Nanomedicine ; 15: 5561-5571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801704

RESUMO

Purpose: Platinum/paclitaxel-based chemotherapy is the strategy for ovarian cancer, but chemoresistance, inherent or acquired, occurs and hinders therapy. Therefore, further understanding of the mechanisms of drug resistance and adoption of novel therapeutic strategies are urgently needed. Methods: In this study, we report that sphingosine-1-phosphate receptor-1 (S1PR1)-mediated chemoresistance for ovarian cancer. Then we developed nanoparticles with a hydrophilic PEG2000 chain and a hydrophobic DSPE and biodegradable CaP (calcium ions and phosphate ions) shell with pH sensitivity as a delivery system (CaP-NPs) to carry BAF312, a selective antagonist of S1PR1 (BAF312@CaP-NPs), to overcome the cisplatin (DDP) resistance of the ovarian cancer cell line SKOV3DR. Results: We found that S1PR1 affected acquired chemoresistance in ovarian cancer by increasing the phosphorylated-signal transduction and activators of transcription 3 (P-STAT3) level. The mean size and zeta potential of BAF312@CaP-NPs were 116 ± 4.341 nm and -9.67 ± 0.935 mV, respectively. The incorporation efficiency for BAF312 in the CaP-NPs was 76.1%. The small size of the nanoparticles elevated their enrichment in the tumor, and the degradable CaP shell with smart pH sensitivity of the BAF312@CaP-NPs ensured the release of BAF312 in the acidic tumor niche. BAF312@CaP-NPs caused substantial cytotoxicity in DDP-resistant ovarian cancer cells by downregulating S1PR1 and P-STAT3 levels. Conclusion: We found that BAF312@CaP-NPs act as an effective and selective delivery system for overcoming S1PR1-mediated chemoresistance in ovarian carcinoma by inhibiting S1PR1 and P-STAT3.


Assuntos
Azetidinas/administração & dosagem , Compostos de Benzil/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/genética , Azetidinas/farmacocinética , Compostos de Benzil/farmacocinética , Fosfatos de Cálcio/química , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fosforilação/efeitos dos fármacos , Polietilenoglicóis/química , Fator de Transcrição STAT3/metabolismo , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/metabolismo
12.
J Pharmacol Sci ; 144(3): 147-150, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32800684

RESUMO

Astrocytes are the most abundant glial cells in the central nervous system (CNS), including the spinal cord. Neuronal damage induces astrocytes to become reactive and contribute to various CNS pathologies. Recent studies have demonstrated that astrocytes in the spinal dorsal horn (SDH) become reactive in a transcription factor signal transducer and activator of transcription 3-dependent manner without neuronal damage under chronic itch conditions, causing release of the factor lipocalin-2, leading to induction of sensitization of gastrin releasing peptide-induced chemical itch signaling in the SDH. In this review, we describe recent advances in our understanding of SDH neuronal pathways for itch transmission, the mechanisms of SDH astrocytic activation and its contribution to abnormal itch processing and discuss the role of reactive astrocytes in the SDH in abnormal sensory processing under chronic itch conditions.


Assuntos
Astrócitos/fisiologia , Prurido/etiologia , Corno Dorsal da Medula Espinal/citologia , Doença Crônica , Peptídeo Liberador de Gastrina/metabolismo , Humanos , Lipocalina-2/metabolismo , Vias Neurais , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
13.
Nat Commun ; 11(1): 3383, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32636391

RESUMO

The endogenous repair process can result in recovery after acute kidney injury (AKI) with adaptive proliferation of tubular epithelial cells, but repair can also lead to fibrosis and progressive kidney disease. There is currently limited knowledge about transcriptional regulators regulating these repair programs. Herein we establish the enhancer and super-enhancer landscape after AKI by ChIP-seq in uninjured and repairing kidneys on day two after ischemia reperfusion injury (IRI). We identify key transcription factors including HNF4A, GR, STAT3 and STAT5, which show specific binding at enhancer and super-enhancer sites, revealing enhancer dynamics and transcriptional changes during kidney repair. Loss of bromodomain-containing protein 4 function before IRI leads to impaired recovery after AKI and increased mortality. Our comprehensive analysis of epigenetic changes after kidney injury in vivo has the potential to identify targets for therapeutic intervention. Importantly, our data also call attention to potential caveats involved in use of BET inhibitors in patients at risk for AKI.


Assuntos
Lesão Renal Aguda/genética , Elementos Facilitadores Genéticos , Túbulos Renais/citologia , Lesão Renal Aguda/metabolismo , Motivos de Aminoácidos , Animais , Sítios de Ligação , Proliferação de Células , Epigênese Genética , Fibrose , Fator 4 Nuclear de Hepatócito/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas Nucleares , Receptores de Glucocorticoides/metabolismo , Elementos Reguladores de Transcrição , Traumatismo por Reperfusão/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Fatores de Transcrição , Transcrição Genética
14.
Nat Commun ; 11(1): 3737, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32719355

RESUMO

Glucocorticoids (GC) are a controversial yet commonly used intervention in the clinical management of acute inflammatory conditions, including sepsis or traumatic injury. In the context of major trauma such as surgery, concerns have been raised regarding adverse effects from GC, thereby necessitating a better understanding of how GCs modulate the immune response. Here we report the results of a randomized controlled trial (NCT02542592) in which we employ a high-dimensional mass cytometry approach to characterize innate and adaptive cell signaling dynamics after a major surgery (primary outcome) in patients treated with placebo or methylprednisolone (MP). A robust, unsupervised bootstrap clustering of immune cell subsets coupled with random forest analysis shows profound (AUC = 0.92, p-value = 3.16E-8) MP-induced alterations of immune cell signaling trajectories, particularly in the adaptive compartments. By contrast, key innate signaling responses previously associated with pain and functional recovery after surgery, including STAT3 and CREB phosphorylation, are not affected by MP. These results imply cell-specific and pathway-specific effects of GCs, and also prompt future studies to examine GCs' effects on clinical outcomes likely dependent on functional adaptive immune responses.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Artroplastia de Quadril/efeitos adversos , Glucocorticoides/farmacologia , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/imunologia , Doença Aguda , Idoso , Estudos de Casos e Controles , Método Duplo-Cego , Fadiga/tratamento farmacológico , Feminino , Humanos , Masculino , Metilprednisolona/farmacologia , Metilprednisolona/uso terapêutico , Inibidor de NF-kappaB alfa/metabolismo , Dor/tratamento farmacológico , Fenótipo , Fosforilação , Fator de Transcrição STAT3/metabolismo , Resultado do Tratamento
15.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 40(7): 1001-1007, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32701233

RESUMO

OBJECTIVE: To explore the effects of taurolithocholic acid (tLCA) and chenodeoxycholic acid (CDCA) on the expression of aorexigenic neuropeptide in mouse hypothalamus GT1-7 cells. METHODS: Mouse hypothalamic GT1-7 cells were treated with culture medium containing 10% FBS (control group, n=3) or with 10 nmol/L, 100 nmol/L, 1 µmol/L and 10 µmol/L tLCA (tLCA group, n=3) or CDCA (CDCA group, n=3) for 12, 24 or 48 h. Real-time PCR was performed to determine the expression levels of proopiomelanocortin (POMC) mRNA in the cells, and the production levels of α-melanocyte-stimulating hormone (α-MSH) were assessed using an ELISA kit. Signal transduction and activator of transcription 3 phosphorylation (p-STAT3), threonine kinase phosphorylation (p-AKT), suppressor of cytokine signaling 3 (SOCS3), G protein-coupled bile acid receptor-1 (TGR5) and farnesoid X receptor (FXR) protein were detected by Western blotting. RESULTS: Western blotting results showed that mouse hypothalamic GT1-7 cells expressed two bile acid receptors, TGR5 and FXR, whose expressions were regulated by bile acids. Real-time PCR showed that the expression of POMC mRNA was significantly increased in the cells after treatment with 10 µmol/L tLCA or CDCA for 24 h. POMC-derived anorexigenic peptide α-MSH increased significantly in GT1-7 cells after treatment with 10 µmol/L tLCA or CDCA for 24 h. Treatment of the cells with tLCA or CDCA significantly increased the expressions of intracellular signaling proteins including p-STAT3, p-AKT and SOCS3. CONCLUSIONS: Mouse hypothalamic GT1-7 cells express bile acid receptors TGR5 and FXR. Bile acids tLCA or CDCA can promote the expression of POMC mRNA and increase the production of the anorexigenic peptide α-MSH. The intracellular signaling proteins p-AKT, p-STAT3 and SOCS3 are likely involved in bile acid-induced anorexigenic peptide production.


Assuntos
Ácido Quenodesoxicólico , Regulação da Expressão Gênica , Pró-Opiomelanocortina , Transdução de Sinais , Ácido Taurolitocólico , alfa-MSH , Animais , Linhagem Celular , Ácido Quenodesoxicólico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipotálamo/citologia , Camundongos , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Pró-Opiomelanocortina/genética , RNA Mensageiro/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Ácido Taurolitocólico/farmacologia , alfa-MSH/genética
16.
PLoS One ; 15(7): e0235573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609742

RESUMO

Diabetes mellitus is a well-known risk factor for pancreatic cancer. We focused on hyperglycemia, a main feature of diabetes mellitus, and uncovered its effect on precancerous pancreatic intraepithelial neoplasia (PanIN) progression. In vivo induction of hyperglycemia with 100 mg/kg streptozotocin in KrasLSL G12D Pdx1Cre (KP) mice promoted the PanIN formation and progression. Preconditioning with a high- or low-glucose medium for 28 days showed that a high-glucose environment increased cell viability and sphere formation in PANC-1, a Kras-mutant human pancreatic ductal adenocarcinoma cell line, and mPKC1, a Kras-mutant murine pancreatic cancer cell line. In contrast, no changes were observed in BxPC3, a Kras-wild-type human pancreatic cancer cell line. Orthotopic injection of mPKC1 into the pancreatic tails of BL6/J mice showed that cells maintained in high-glucose medium grew into larger tumors than did those maintained in low-glucose medium. Hyperglycemia strengthened the STAT3 phosphorylation, which was accompanied by elevated MYC expression in Kras-mutant cells. Immunohistochemistry showed stronger phosphorylated STAT3 (pSTAT3) and MYC staining in PanINs from diabetic KP mice than in those from euglycemic counterparts. STAT3 inhibition with 1 µM STAT3 inhibitor STATTIC in Kras-mutant pancreatic cell lines blocked the cell viability- and sphere formation-enhancing effects of the hyperglycemic environment and reversed the elevated pSTAT3 and MYC expression. MYC knockdown did not affect cell viability but did reduce sphere formation. No decrease in pSTAT3 expression was observed upon siMYC treatment. In conclusion, hyperglycemia, on a Kras-mutant background, aggravates the PanIN progression, which is accompanied by elevated pSTAT3 and MYC expression.


Assuntos
Progressão da Doença , Hiperglicemia/complicações , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Humanos , Camundongos , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fosforilação , Proteínas Proto-Oncogênicas p21(ras)/genética
17.
Cell Prolif ; 53(8): e12856, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32648622

RESUMO

OBJECTIVES: Glial cell activation contributes to the inflammatory response and occurrence of epilepsy. Our preliminary study demonstrated that the long non-coding RNA, H19, promotes hippocampal glial cell activation during epileptogenesis. However, the precise mechanisms underlying this effect remain unclear. MATERIALS AND METHODS: H19 and let-7b were overexpressed or silenced using an adeno-associated viral vector in vivo. Their expression in a kainic acid-induced epilepsy model was evaluated by real-time quantitative PCR, fluorescence in situ hybridization, and cytoplasmic and nuclear RNA isolation. A dual-luciferase reporter assay was used to evaluate the direct binding of let-7b to its target genes and H19. Western blot, video camera monitoring and Morris water maze were performed to confirm the role of H19 and let7b on epileptogenesis. RESULTS: H19 was increased in rat hippocampus neurons after status epilepticus, which might be due to epileptic seizure-induced hypoxia. Increased H19 aggravated the epileptic seizures, memory impairment and mossy fibre sprouting of the epileptic rats. H19 could competitively bind to let-7b to suppress its expression. Overexpression of let-7b inhibited hippocampal glial cell activation, inflammatory response and epileptic seizures by targeting Stat3. Moreover, overexpressed H19 reversed the inhibitory effect of let-7b on glial cell activation. CONCLUSIONS: LncRNA H19 could competitively bind to let-7b to promote hippocampal glial cell activation and epileptic seizures by targeting Stat3 in a rat model of temporal lobe epilepsy.


Assuntos
Epilepsia do Lobo Temporal/genética , Hipocampo/metabolismo , MicroRNAs/genética , RNA Longo não Codificante/genética , Fator de Transcrição STAT3/metabolismo , Animais , Modelos Animais de Doenças , Epilepsia/genética , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Genes Supressores de Tumor/fisiologia , Masculino , Ratos Sprague-Dawley , Convulsões/genética , Convulsões/metabolismo
18.
Nat Commun ; 11(1): 3420, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647127

RESUMO

Remyelination of the peripheral and central nervous systems (PNS and CNS, respectively) is a prerequisite for functional recovery after lesion. However, this process is not always optimal and becomes inefficient in the course of multiple sclerosis. Here we show that, when acetylated, eukaryotic elongation factor 1A1 (eEF1A1) negatively regulates PNS and CNS remyelination. Acetylated eEF1A1 (Ac-eEF1A1) translocates into the nucleus of myelinating cells where it binds to Sox10, a key transcription factor for PNS and CNS myelination and remyelination, to drag Sox10 out of the nucleus. We show that the lysine acetyltransferase Tip60 acetylates eEF1A1, whereas the histone deacetylase HDAC2 deacetylates eEF1A1. Promoting eEF1A1 deacetylation maintains the activation of Sox10 target genes and increases PNS and CNS remyelination efficiency. Taken together, these data identify a major mechanism of Sox10 regulation, which appears promising for future translational studies on PNS and CNS remyelination.


Assuntos
Fator 1 de Elongação de Peptídeos/metabolismo , Remielinização/genética , Ativação Transcricional/genética , Acetilação , Envelhecimento/metabolismo , Animais , Desdiferenciação Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/metabolismo , Lisina Acetiltransferase 5/metabolismo , Camundongos , Modelos Biológicos , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Sistema Nervoso Periférico/efeitos dos fármacos , Sistema Nervoso Periférico/fisiologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Remielinização/efeitos dos fármacos , Fatores de Transcrição SOXE/metabolismo , Fator de Transcrição STAT3/metabolismo , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Teofilina/farmacologia , Transativadores/metabolismo , Ativação Transcricional/efeitos dos fármacos
19.
Gene ; 757: 144931, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32640308

RESUMO

OBJECTIVE: The aim of this study is to investigate the role of close homolog of L1 (CHL1) on inflammatory bowel disease (IBD), and the correlation with the balance of Th17/Treg. METHODS: Dextran sodium sulfate (DSS)-induced IBD mice model was established. CHL1 knockout (KO) mice and CHL1 wild-type (WT) mice were subjected to DSS. CHL1 expression was detected using qRT-PCR. Weight was recorded daily, and disease activity index (DAI) score was assessed. The colon length and histological changes were measured. The number of neutrophils, macrophages and T cells was observed by immunohistochemistry. The expression of inflammatory cytokines and the proportion of Th17/Treg cells were detected by qRT-PCR and flow cytometry. The expression of RORγt, STAT3 and Foxp3 was detected by using immunohistochemistry and Western blot. RESULTS: CHL1 expression was upregulated in DSS-induced IBD mice. DSS-CHLl-KO mice exhibited less weight loss than the DSS-CHLl-WT mice. The DAI score and histological score were decreased in DSS-CHLl-KO mice compared with DSS-CHLl-WT mice, while colon length was increased. Number of neutrophils, macrophages and T cells, and expression of TNF-α, IL-6, IL-17A, IL-21 and IL-23 were decreased in DSS-CHLl-KO mice, while IL-10 expression was increased. Moreover, CHL1-deficient inhibited Th17 cells differentiation and promoted Treg cells differentiation in IBD mice. CHL1-deficient also inhibited the expression of RORγt and STAT3, and promoted the expression of Foxp3 in IBD mice. CONCLUSION: CHL1-deficient reduces the inflammatory response by regulating the balance of Th17/Treg in mice with IBD. CHL1 is expected to be a new target for the treatment of IBD.


Assuntos
Moléculas de Adesão Celular/genética , Doenças Inflamatórias Intestinais/genética , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Moléculas de Adesão Celular/deficiência , Diferenciação Celular , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/imunologia , Interleucinas/genética , Interleucinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/citologia , Células Th17/citologia
20.
Life Sci ; 257: 118088, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663573

RESUMO

AIMS: Bone marrow stromal cells (BMSCs) have been reported to interact with multiple myeloma (MM) and exert a vital function of the survival of MM cells. Heme oxygenase-1 (HO-1), a cytoprotective enzyme, has the potential to become a hematological malignancies targeted gene. This study aimed to investigate the role of HO-1 in MM resistance of BMSCs and its possible mechanisms. MAIN METHODS: In this study, the expression of related proteins was detected by RT-qPCR and Western blot. HO-1 expression was regulated by lentivirus transfection. Cell viability and apoptosis were detected by Flow cytometry and CCK-8. Cytokine secretion was assayed by ELISA. The survival and carcinogenic abilities was detected by clone formation assay. KEY FINDINGS: HO-1 expression in the BMSCs of stage III MM patients was substantially increased, compared with that of healthy donors and stage I/II patients. The results of co-culture of BMSCs and MM cells indicated that, the upregulated HO-1 inhibited the apoptosis of co-cultured MM cells, while downregulated HO-1 promoted the chemosensitivity of co-cultured MM cells, moreover, the upregulated HO-1 in BMSCs increased the colony-formation ability of MM cells. This protective capability may be regulated by CXCL12/CXCR4 signaling. High HO-1 expression in BMSCs can promote the phosphorylation of the JAK2/STAT3 pathway, thereby increasing secretion of SDF-1 in BMSCs and activating CXCL12/CXCR4 signaling. In addition, direct contact between BMSCs and MM cells may cause drug resistance. SIGNIFICANCE: These results indicated that the regulation of HO-1 in BMSCs may be a new effective method of MM therapy.


Assuntos
Antineoplásicos/farmacologia , Heme Oxigenase-1/genética , Células-Tronco Mesenquimais/citologia , Mieloma Múltiplo/patologia , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Estudos de Casos e Controles , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Janus Quinase 2/metabolismo , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Estadiamento de Neoplasias , Fator de Transcrição STAT3/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA