Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 316
Filtrar
1.
Cell ; 162(5): 974-86, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26317466

RESUMO

We show that DNA methyltransferase inhibitors (DNMTis) upregulate immune signaling in cancer through the viral defense pathway. In ovarian cancer (OC), DNMTis trigger cytosolic sensing of double-stranded RNA (dsRNA) causing a type I interferon response and apoptosis. Knocking down dsRNA sensors TLR3 and MAVS reduces this response 2-fold and blocking interferon beta or its receptor abrogates it. Upregulation of hypermethylated endogenous retrovirus (ERV) genes accompanies the response and ERV overexpression activates the response. Basal levels of ERV and viral defense gene expression significantly correlate in primary OC and the latter signature separates primary samples for multiple tumor types from The Cancer Genome Atlas into low versus high expression groups. In melanoma patients treated with an immune checkpoint therapy, high viral defense signature expression in tumors significantly associates with durable clinical response and DNMTi treatment sensitizes to anti-CTLA4 therapy in a pre-clinical melanoma model.


Assuntos
Metilação de DNA/efeitos dos fármacos , Interferon Tipo I/imunologia , Melanoma/imunologia , Melanoma/terapia , Animais , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/antagonistas & inibidores , Retrovirus Endógenos/genética , Feminino , Humanos , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/terapia , RNA de Cadeia Dupla/metabolismo
3.
PLoS Pathog ; 20(8): e1012397, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39116040

RESUMO

As the Coronavirus Disease 2019 (COVID-19) pandemic continues, there is a growing concern regarding the relationship between viral infections and neuropathic pain. Chronic neuropathic pain resulting from virus-induced neural dysfunction has emerged as a significant issue currently faced. However, the molecular mechanisms underlying this phenomenon remain unclear, and clinical treatment outcomes are often suboptimal. Therefore, delving into the relationship between viral infections and neuropathic pain, exploring the pathophysiological characteristics and molecular mechanisms of different viral pain models, can contribute to the discovery of potential therapeutic targets and methods, thereby enhancing pain relief and improving the quality of life for patients. This review focuses on HIV-related neuropathic pain (HNP), postherpetic neuralgia (PHN), and neuropathic pain caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infections, examining rodent models and relevant cellular molecular pathways. Through elucidating the connection between viral infections and neuropathic pain, it aims to delineate the current limitations and challenges faced by treatments, thereby providing insights and directions for future clinical practice and research.


Assuntos
COVID-19 , Neuralgia , SARS-CoV-2 , Humanos , Neuralgia/virologia , Neuralgia/terapia , Neuralgia/etiologia , Animais , COVID-19/complicações , COVID-19/virologia , COVID-19/terapia , Infecções por HIV/complicações , Infecções por HIV/virologia , Infecções por HIV/tratamento farmacológico , Neuralgia Pós-Herpética/virologia , Neuralgia Pós-Herpética/terapia
4.
EMBO Rep ; 25(10): 4337-4357, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39242776

RESUMO

Despite the efficacy of highly active antiretroviral therapy in controlling the incidence and mortality of AIDS, effective interventions for HIV-1-induced neurological damage and cognitive impairment remain elusive. In this study, we found that HIV-1 infection can induce proteolytic cleavage and aberrant aggregation of TAR DNA-binding protein 43 (TDP-43), a pathological protein associated with various severe neurological disorders. The HIV-1 accessory protein Vpu was found to be responsible for the cleavage of TDP-43, as ectopic expression of Vpu alone was sufficient to induce TDP-43 cleavage, whereas HIV-1 lacking Vpu failed to cleave TDP-43. Mechanistically, the cleavage of TDP-43 at Asp89 by HIV-1 relies on Vpu-mediated activation of Caspase 3, and pharmacological inhibition of Caspase 3 activity effectively suppressed the HIV-1-induced aggregation and neurotoxicity of TDP-43. Overall, these results suggest that TDP-43 is a conserved host target of HIV-1 Vpu and provide evidence for the involvement of TDP-43 dysregulation in the neural pathogenesis of HIV-1.


Assuntos
Caspase 3 , Proteínas de Ligação a DNA , HIV-1 , Proteínas do Vírus da Imunodeficiência Humana , Proteólise , Proteínas Virais Reguladoras e Acessórias , Humanos , Caspase 3/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Células HEK293 , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Infecções por HIV/tratamento farmacológico , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Proteínas do Vírus da Imunodeficiência Humana/genética , Neurônios/metabolismo , Neurônios/virologia , Proteínas Virais Reguladoras e Acessórias/metabolismo
6.
Nature ; 579(7798): 284-290, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103175

RESUMO

Cancer recurrence after surgery remains an unresolved clinical problem1-3. Myeloid cells derived from bone marrow contribute to the formation of the premetastatic microenvironment, which is required for disseminating tumour cells to engraft distant sites4-6. There are currently no effective interventions that prevent the formation of the premetastatic microenvironment6,7. Here we show that, after surgical removal of primary lung, breast and oesophageal cancers, low-dose adjuvant epigenetic therapy disrupts the premetastatic microenvironment and inhibits both the formation and growth of lung metastases through its selective effect on myeloid-derived suppressor cells (MDSCs). In mouse models of pulmonary metastases, MDSCs are key factors in the formation of the premetastatic microenvironment after resection of primary tumours. Adjuvant epigenetic therapy that uses low-dose DNA methyltransferase and histone deacetylase inhibitors, 5-azacytidine and entinostat, disrupts the premetastatic niche by inhibiting the trafficking of MDSCs through the downregulation of CCR2 and CXCR2, and by promoting MDSC differentiation into a more-interstitial macrophage-like phenotype. A decreased accumulation of MDSCs in the premetastatic lung produces longer periods of disease-free survival and increased overall survival, compared with chemotherapy. Our data demonstrate that, even after removal of the primary tumour, MDSCs contribute to the development of premetastatic niches and settlement of residual tumour cells. A combination of low-dose adjuvant epigenetic modifiers that disrupts this premetastatic microenvironment and inhibits metastases may permit an adjuvant approach to cancer therapy.


Assuntos
Epigênese Genética , Terapia Genética , Células Supressoras Mieloides/fisiologia , Neoplasias/terapia , Microambiente Tumoral , Animais , Azacitidina/farmacologia , Benzamidas/farmacologia , Diferenciação Celular , Movimento Celular/efeitos dos fármacos , Quimioterapia Adjuvante , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Camundongos , Células Supressoras Mieloides/citologia , Metástase Neoplásica/terapia , Neoplasias/cirurgia , Piridinas/farmacologia , Receptores CCR2/genética , Receptores de Interleucina-8B/genética , Microambiente Tumoral/efeitos dos fármacos
7.
J Virol ; 98(6): e0043424, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38690875

RESUMO

The globally reemerging respiratory pathogen enterovirus D68 (EV-D68) is implicated in outbreaks of severe respiratory illness and associated with acute flaccid myelitis. However, there remains a lack of effective treatments for EV-D68 infection. In this work, we found that the host Toll-like receptor 7 (TLR7) proteins, which function as powerful innate immune sensors, were selectively elevated in expression in response to EV-D68 infection. Subsequently, we investigated the impact of Vesatolimod (GS-9620), a Toll-like receptor 7 agonist, on EV-D68 replication. Our findings revealed that EV-D68 infection resulted in increased mRNA levels of TLR7. Treatment with Vesatolimod significantly inhibited EV-D68 replication [half maximal effective concentration (EC50) = 0.1427 µM] without inducing significant cytotoxicity at virucidal concentrations. Although Vesatolimod exhibited limited impact on EV-D68 attachment, it suppressed RNA replication and viral protein synthesis after virus entry. Vesatolimod broadly inhibited the replication of circulating isolated strains of EV-D68. Furthermore, our findings demonstrated that treatment with Vesatolimod conferred resistance to both respiratory and neural cells against EV-D68 infection. Overall, these results present a promising strategy for drug development by pharmacologically activating TLR7 to initiate an antiviral state in EV-D68-infected cells selectively.IMPORTANCEConventional strategies for antiviral drug development primarily focus on directly targeting viral proteases or key components, as well as host proteins involved in viral replication. In this study, based on our intriguing discovery that enterovirus D68 (EV-D68) infection specifically upregulates the expression of immune sensor Toll-like receptor 7 (TLR7) protein, which is either absent or expressed at low levels in respiratory cells, we propose a potential antiviral approach utilizing TLR7 agonists to activate EV-D68-infected cells into an anti-viral defense state. Notably, our findings demonstrate that pharmacological activation of TLR7 effectively suppresses EV-D68 replication in respiratory tract cells through a TLR7/MyD88-dependent mechanism. This study not only presents a promising drug candidate and target against EV-D68 dissemination but also highlights the potential to exploit unique alterations in cellular innate immune responses induced by viral infections, selectively inducing a defensive state in infected cells while safeguarding uninfected normal cells from potential adverse effects associated with therapeutic interventions.


Assuntos
Antivirais , Enterovirus Humano D , Receptor 7 Toll-Like , Replicação Viral , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/metabolismo , Humanos , Replicação Viral/efeitos dos fármacos , Enterovirus Humano D/efeitos dos fármacos , Antivirais/farmacologia , Indóis/farmacologia , Infecções por Enterovirus/virologia , Imunidade Inata/efeitos dos fármacos , Linhagem Celular , Internalização do Vírus/efeitos dos fármacos , Pteridinas
8.
J Virol ; 98(2): e0199423, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38240591

RESUMO

Following the successful control of poliovirus, the re-emergence of respiratory enterovirus D68 (EV-D68), a prominent non-polio enterovirus, has become a serious public health concern worldwide. Host innate immune responses are the primary defense against EV-D68 invasion; however, the mechanism underlying viral evasion of the antiviral activity of interferons (IFN) remains unclear. In this study, we found that EV-D68 inhibited type I IFN signaling by cleaving signal transducer and activator of transcription 1 (STAT1), a crucial factor in cellular responses to interferons and other cytokines. We observed that the prototype and circulating EV-D68 strains conserved their ability to induce STAT1 cleavage and attenuate IFN signal transduction. Further investigation revealed that EV-D68 3C protease cleaves STAT1 at the 131Q residue. Interestingly, not all enterovirus-encoded 3C proteases exhibited this ability. EV-D68 and poliovirus 3C proteases efficiently induced STAT1 cleavage; whereas, 3C proteases from EV-A71, coxsackievirus A16, and echoviruses did not. STAT1 cleavage also abolished the nuclear translocation capacity of STAT1 in response to IFN stimulation to activate downstream signaling elements. Overall, these results suggest that STAT1, targeted by viral protease 3C, is utilized by EV-D68 to subvert the host's innate immune response.IMPORTANCEEnterovirus D68 (EV-D68) has significantly transformed over the past decade, evolving from a rare pathogen to a potential pandemic pathogen. The interferon (IFN) signaling pathway is an important defense mechanism and therapeutic target for the host to resist viral invasion. Previous studies have reported that the EV-D68 virus blocks or weakens immune recognition and IFN production in host cells through diverse strategies; however, the mechanisms of EV-D68 resistance to IFN signaling have not been fully elucidated. Our study revealed that EV-D68 relies on its own encoded protease, 3C, to directly cleave signal transducer and activator of transcription 1 (STAT1), a pivotal transduction component in the IFN signaling pathway, disrupting the IFN-mediated antiviral response. Previous studies on human enteroviruses have not documented direct cleavage of the STAT1 protein to evade cellular immune defenses. However, not all enteroviral 3C proteins can cleave STAT1. These findings highlight the diverse evolutionary strategies different human enteroviruses employ to evade host immunity.


Assuntos
Proteases Virais 3C , Enterovirus Humano D , Interferon Tipo I , Transdução de Sinais , Humanos , Proteases Virais 3C/metabolismo , Antígenos Virais/metabolismo , Antivirais/farmacologia , Cisteína Endopeptidases/metabolismo , Enterovirus Humano D/fisiologia , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Imunidade Inata , Interferon Tipo I/metabolismo , Peptídeo Hidrolases/metabolismo , Proteólise , Fator de Transcrição STAT1/metabolismo , Proteínas Virais/metabolismo
9.
J Virol ; 98(2): e0190923, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38289118

RESUMO

Pyroptosis, a pro-inflammatory programmed cell death, has been implicated in the pathogenesis of coronavirus disease 2019 and other viral diseases. Gasdermin family proteins (GSDMs), including GSDMD and GSDME, are key regulators of pyroptotic cell death. However, the mechanisms by which virus infection modulates pyroptosis remain unclear. Here, we employed a mCherry-GSDMD fluorescent reporter assay to screen for viral proteins that impede the localization and function of GSDMD in living cells. Our data indicated that the main protease NSP5 of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) blocked GSDMD-mediated pyroptosis via cleaving residues Q29 and Q193 of GSDMD. While another SARS-CoV-2 protease, NSP3, cleaved GSDME at residue G370 but activated GSDME-mediated pyroptosis. Interestingly, respiratory enterovirus EV-D68-encoded proteases 3C and 2A also exhibit similar differential regulation on the functions of GSDMs by inactivating GSDMD but initiating GSDME-mediated pyroptosis. EV-D68 infection exerted oncolytic effects on human cancer cells by inducing pyroptotic cell death. Our findings provide insights into how respiratory viruses manipulate host cell pyroptosis and suggest potential targets for antiviral therapy as well as cancer treatment.IMPORTANCEPyroptosis plays a crucial role in the pathogenesis of coronavirus disease 2019, and comprehending its function may facilitate the development of novel therapeutic strategies. This study aims to explore how viral-encoded proteases modulate pyroptosis. We investigated the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and respiratory enterovirus D68 (EV-D68) proteases on host cell pyroptosis. We found that SARS-CoV-2-encoded proteases NSP5 and NSP3 inactivate gasdermin D (GSDMD) but initiate gasdermin E (GSDME)-mediated pyroptosis, respectively. We also discovered that another respiratory virus EV-D68 encodes two distinct proteases 2A and 3C that selectively trigger GSDME-mediated pyroptosis while suppressing the function of GSDMD. Based on these findings, we further noted that EV-D68 infection triggers pyroptosis and produces oncolytic effects in human carcinoma cells. Our study provides new insights into the molecular mechanisms underlying virus-modulated pyroptosis and identifies potential targets for the development of antiviral and cancer therapeutics.


Assuntos
Endopeptidases , Enterovirus Humano D , Interações entre Hospedeiro e Microrganismos , Vírus Oncolíticos , Piroptose , SARS-CoV-2 , Humanos , Linhagem Celular Tumoral , COVID-19/metabolismo , COVID-19/terapia , COVID-19/virologia , Endopeptidases/genética , Endopeptidases/metabolismo , Enterovirus Humano D/enzimologia , Enterovirus Humano D/genética , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Gasderminas/antagonistas & inibidores , Gasderminas/genética , Gasderminas/metabolismo , Terapia Viral Oncolítica , Vírus Oncolíticos/enzimologia , Vírus Oncolíticos/genética , SARS-CoV-2/enzimologia , SARS-CoV-2/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo
10.
Nucleic Acids Res ; 51(17): 9475-9490, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37587714

RESUMO

African swine fever virus (ASFV) is highly contagious and can cause lethal disease in pigs. Although it has been extensively studied in the past, no vaccine or other useful treatment against ASFV is available. The genome of ASFV encodes more than 170 proteins, but the structures and functions for the majority of the proteins remain elusive, which hindered our understanding on the life cycle of ASFV and the development of ASFV-specific inhibitors. Here, we report the structural and biochemical studies of the highly conserved C962R protein of ASFV, showing that C962R is a multidomain protein. The N-terminal AEP domain is responsible for the DNA polymerization activity, whereas the DNA unwinding activity is catalyzed by the central SF3 helicase domain. The middle PriCT2 and D5_N domains and the C-terminal Tail domain all contribute to the DNA unwinding activity of C962R. C962R preferentially works on forked DNA, and likely functions in Base-excision repair (BER) or other repair pathway in ASFV. Although it is not essential for the replication of ASFV, C962R can serve as a model and provide mechanistic insight into the replicative primase proteins from many other species, such as nitratiruptor phage NrS-1, vaccinia virus (VACV) and other viruses.


Assuntos
Vírus da Febre Suína Africana , Proteínas Virais , Animais , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/enzimologia , Suínos , Proteínas Virais/química , Proteínas Virais/metabolismo , DNA Topoisomerases Tipo I/química , Replicação do DNA
11.
Nucleic Acids Res ; 51(9): 4625-4636, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37013991

RESUMO

Cadmium (Cd) is one of the most toxic heavy metals. Exposure to Cd can impair the functions of the kidney, respiratory system, reproductive system and skeletal system. Cd2+-binding aptamers have been extensively utilized in the development of Cd2+-detecting devices; however, the underlying mechanisms remain elusive. This study reports four Cd2+-bound DNA aptamer structures, representing the only Cd2+-specific aptamer structures available to date. In all the structures, the Cd2+-binding loop (CBL-loop) adopts a compact, double-twisted conformation and the Cd2+ ion is mainly coordinated with the G9, C12 and G16 nucleotides. Moreover, T11 and A15 within the CBL-loop form one regular Watson-Crick pair and stabilize the conformation of G9. The conformation of G16 is stabilized by the G8-C18 pair of the stem. By folding and/or stabilizing the CBL-loop, the other four nucleotides of the CBL-loop also play important roles in Cd2+ binding. Similarly to the native sequence, crystal structures, circular dichroism spectrum and isothermal titration calorimetry analysis confirm that several variants of the aptamer can recognize Cd2+. This study not only reveals the underlying basis for the binding of Cd2+ ions with the aptamer, but also extends the sequence for the construction of novel metal-DNA complex.


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/química , Cádmio , Conformação Molecular , DNA
12.
Nano Lett ; 24(17): 5301-5307, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625005

RESUMO

The accurate diagnosis of diabetic nephropathy relies on achieving ultrasensitive biosensing for biomarker detection. However, existing biosensors face challenges such as poor sensitivity, complexity, time-consuming procedures, and high assay costs. To address these limitations, we report a WS2-based plasmonic biosensor for the ultrasensitive detection of biomarker candidates in clinical human urine samples associated with diabetic nephropathy. Leveraging plasmonic-based electrochemical impedance microscopy (P-EIM) imaging, we observed a remarkable charge sensitivity in monolayer WS2 single crystals. Our biosensor exhibits an exceptionally low detection limit (0.201 ag/mL) and remarkable selectivity in detecting CC chemokine ligand 2 (CCL2) protein biomarkers, outperforming conventional techniques such as ELISA. This work represents a breakthrough in traditional protein sensors, providing a direction and materials foundation for developing ultrasensitive sensors tailored to clinical applications for biomarker sensing.


Assuntos
Biomarcadores , Técnicas Biossensoriais , Quimiocina CCL2 , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/urina , Nefropatias Diabéticas/diagnóstico , Técnicas Biossensoriais/métodos , Quimiocina CCL2/urina , Biomarcadores/urina , Limite de Detecção , Técnicas Eletroquímicas/métodos
13.
Apoptosis ; 29(9-10): 1309-1329, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38886311

RESUMO

Disulfidptosis is a novel form of cell death that is distinguishable from established programmed cell death pathways such as apoptosis, pyroptosis, autophagy, ferroptosis, and oxeiptosis. This process is characterized by the rapid depletion of nicotinamide adenine dinucleotide phosphate (NADPH) in cells and high expression of solute carrier family 7 member 11 (SLC7A11) during glucose starvation, resulting in abnormal cystine accumulation, which subsequently induces andabnormal disulfide bond formation in actin cytoskeleton proteins, culminating in actin network collapse and disulfidptosis. This review aimed to summarize the underlying mechanisms, influencing factors, comparisons with traditional cell death pathways, associations with related diseases, application prospects, and future research directions related to disulfidptosis.


Assuntos
Morte Celular , Humanos , Morte Celular/genética , Animais , Apoptose/genética , NADP/metabolismo , Autofagia/genética , Glucose/metabolismo , Ferroptose/genética
14.
Hum Genet ; 143(3): 263-277, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38451291

RESUMO

Neural tube defects (NTDs) are severe malformations of the central nervous system that arise from failure of neural tube closure. HECTD1 is an E3 ubiquitin ligase required for cranial neural tube closure in mouse models. NTDs in the Hectd1 mutant mouse model are due to the failure of cranial mesenchyme morphogenesis during neural fold elevation. Our earlier research has linked increased extracellular heat shock protein 90 (eHSP90) secretion to aberrant cranial mesenchyme morphogenesis in the Hectd1 model. Furthermore, overexpression of HECTD1 suppresses stress-induced eHSP90 secretion in cell lines. In this study, we report the identification of five rare HECTD1 missense sequence variants in NTD cases. The variants were found through targeted next-generation sequencing in a Chinese cohort of 352 NTD cases and 224 ethnically matched controls. We present data showing that HECTD1 is a highly conserved gene, extremely intolerant to loss-of-function mutations and missense changes. To evaluate the functional consequences of NTD-associated missense variants, functional assays in HEK293T cells were performed to examine protein expression and the ability of HECTD1 sequence variants to suppress eHSP90 secretion. One NTD-associated variant (A1084T) had significantly reduced expression in HEK293T cells. All five NTD-associated variants (p.M392V, p.T801I, p.I906V, p.A1084T, and p.P1835L) reduced regulation of eHSP90 secretion by HECTD1, while a putative benign variant (p.P2474L) did not. These findings are the first association of HECTD1 sequence variation with NTDs in humans.


Assuntos
Mutação de Sentido Incorreto , Defeitos do Tubo Neural , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Defeitos do Tubo Neural/genética , Células HEK293 , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Feminino , Masculino , Camundongos , Animais
15.
J Virol ; 97(4): e0042523, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37039659

RESUMO

Enterovirus D68 (EV-D68), which causes severe respiratory diseases and irreversible central nervous system damage, has become a serious public health problem worldwide. However, the mechanisms by which EV-D68 exerts neurotoxicity remain unclear. Thus, we aimed to analyze the effects of EV-D68 infection on the cleavage, subcellular translocation, and pathogenic aggregation of TAR DNA-binding protein 43 kDa (TDP-43) in respiratory or neural cells. The results showed that EV-D68-encoded proteases 2A and 3C induced TDP-43 translocation and cleavage, respectively. Specifically, 3C cleaved residue 327Q of TDP-43. The 3C-mediated cleaved TDP-43 fragments had substantially decreased protein solubility compared with the wild-type TDP-43. Hence, 3C activity promoted TDP-43 aggregation, which exerted cytotoxicity to diverse human cells, including glioblastoma T98G cells. The effects of commercially available antiviral drugs on 3C-mediated TDP-43 cleavage were screened, and the results revealed lopinavir as a potent inhibitor of EV-D68 3C protease. Overall, these results suggested TDP-43 as a conserved host target of EV-D68 3C. This study is the first to provide evidence on the involvement of TDP-43 dysregulation in EV-D68 pathogenesis. IMPORTANCE Over the past decade, the incidence of enterovirus D68 (EV-D68) infection has increased worldwide. EV-D68 infection can cause different respiratory symptoms and severe neurological complications, including acute flaccid myelitis. Thus, elucidating the mechanisms underlying EV-D68 toxicity is important to develop novel methods to prevent EV-D68 infection-associated diseases. This study shows that EV-D68 infection triggers the translocalization, cleavage, and aggregation of TDP-43, an intracellular protein closely related to degenerative neurological disorders. The viral protease 3C decreased TDP-43 solubility, thereby exerting cytotoxicity to host cells, including human glioblastoma cells. Thus, counteracting 3C activity is an effective strategy to relieve EV-D68-triggered cell death. Cytoplasmic aggregation of TDP-43 is a hallmark of degenerative diseases, contributing to neural cell damage and central nervous system (CNS) disorders. The findings of this study on EV-D68-induced TDP-43 formation extend our understanding of virus-mediated cytotoxicity and the potential risks of TDP-43 dysfunction-related cognitive impairment and neurological symptoms in infected patients.


Assuntos
Proteínas de Ligação a DNA , Infecções por Enterovirus , Humanos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/farmacologia , Enterovirus Humano D , Infecções por Enterovirus/fisiopatologia , Infecções por Enterovirus/virologia , Linhagem Celular Tumoral , Proteases Virais 3C/metabolismo , Agregação Patológica de Proteínas/genética , Lopinavir/farmacologia , Proteólise/efeitos dos fármacos , Inativação Gênica , Inibidores de Proteases/farmacologia
16.
J Transl Med ; 22(1): 229, 2024 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433193

RESUMO

Natural killer (NK) cells are unique from other immune cells in that they can rapidly kill multiple neighboring cells without the need for antigenic pre-sensitization once the cells display surface markers associated with oncogenic transformation. Given the dynamic role of NK cells in tumor surveillance, NK cell-based immunotherapy is rapidly becoming a "new force" in tumor immunotherapy. However, challenges remain in the use of NK cell immunotherapy in the treatment of solid tumors. Many metabolic features of the tumor microenvironment (TME) of solid tumors, including oxygen and nutrient (e.g., glucose, amino acids) deprivation, accumulation of specific metabolites (e.g., lactate, adenosine), and limited availability of signaling molecules that allow for metabolic reorganization, multifactorial shaping of the immune-suppressing TME impairs tumor-infiltrating NK cell function. This becomes a key barrier limiting the success of NK cell immunotherapy in solid tumors. Restoration of endogenous NK cells in the TME or overt transfer of functionally improved NK cells holds great promise in cancer therapy. In this paper, we summarize the metabolic biology of NK cells, discuss the effects of TME on NK cell metabolism and effector functions, and review emerging strategies for targeting metabolism-improved NK cell immunotherapy in the TME to circumvent these barriers to achieve superior efficacy of NK cell immunotherapy.


Assuntos
Reprogramação Metabólica , Neoplasias , Humanos , Microambiente Tumoral , Células Matadoras Naturais , Ácido Láctico , Neoplasias/terapia
17.
Neurochem Res ; 49(2): 507-518, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37955815

RESUMO

Previous studies suggested that postsynaptic neuroligin-2 may shift from inhibitory toward excitatory function under pathological pain conditions. We hypothesize that nerve injury may increase the expression of spinal MAM-domain GPI-anchored molecule 1 (MDGA1), which can bind to neuroligin-2 and thereby, alter its interactions with postsynaptic scaffolding proteins and increase spinal excitatory synaptic transmission, leading to neuropathic pain. Western blot, immunofluorescence staining, and co-immunoprecipitation studies were conducted to examine the critical role of MDGA1 in the lumbar spinal cord dorsal horn in rats after spinal nerve ligation (SNL). Small interfering ribonucleic acids (siRNAs) targeting MDGA1 were used to examine the functional roles of MDGA1 in neuropathic pain. Protein levels of MDGA1 in the ipsilateral dorsal horn were significantly upregulated at day 7 post-SNL, as compared to that in naïve or sham rats. The increased levels of GluR1 in the synaptosomal membrane fraction of the ipsilateral dorsal horn tissues at day 7 post-SNL was normalized to near sham level by pretreatment with intrathecal MDGA1 siRNA2308, but not scrambled siRNA or vehicle. Notably, knocking down MDGA1 with siRNAs reduced the mechanical and thermal pain hypersensitivities, and inhibited the increased excitatory synaptic interaction between neuroligin-2 with PSD-95, and prevented the decreased inhibitory postsynaptic interactions between neuroligin-2 and Gephyrin. Our findings suggest that SNL upregulated MDGA1 expression in the dorsal horn, which contributes to the pain hypersensitivity through increasing the net excitatory interaction mediated by neuroligin-2 and surface delivery of GluR1 subunit in dorsal horn neurons.


Assuntos
Neuralgia , Neuroliginas , Ratos , Animais , Regulação para Cima , Ratos Sprague-Dawley , Corno Dorsal da Medula Espinal/metabolismo , Células do Corno Posterior/metabolismo , Neuralgia/patologia , Nervos Espinhais , RNA Interferente Pequeno/metabolismo , Hiperalgesia/metabolismo , Medula Espinal/patologia
18.
Biomacromolecules ; 25(7): 3930-3945, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38820501

RESUMO

The development of a natural, additive-free, absorbable sponge with procoagulant activity for noncompressible hemostasis remains a challenging task. In this study, we extracted high molecular weight keratin (HK) from human hair and transformed it into a hemostatic sponge with a well-interconnected pore structure using a foaming technique, freeze-drying, and oxidation cross-linking. By controlling the cross-linking degree, the resulting sponge demonstrated excellent liquid absorption ability, shape recovery characteristics, and robust mechanical properties. The HK10 sponge exhibited rapid liquid absorption, expanding up to 600% within 5 s. Moreover, the HK sponge showed superior platelet activation and blood cell adhesion capabilities. In SD rat liver defect models, the sponges demonstrated excellent hemostatic performance by sealing the wound and expediting coagulation, reducing the hemostatic time from 825 to 297 s. Furthermore, HK sponges have excellent biosafety, positioning them as a promising absorbable sponge with the potential for the treatment of noncompressible hemostasis.


Assuntos
Hemostasia , Hemostáticos , Queratinas , Ratos Sprague-Dawley , Animais , Ratos , Queratinas/química , Queratinas/farmacologia , Humanos , Hemostasia/efeitos dos fármacos , Hemostáticos/química , Hemostáticos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Masculino , Ativação Plaquetária/efeitos dos fármacos
19.
Inorg Chem ; 63(39): 18103-18109, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39285848

RESUMO

Realizing the regulation of photophysical properties by precisely controlling the molecular composition and configuration, thereby obtaining high-performance optical materials, remains of great significance. Due to the directionality and reversibility of the coordination bond, coordination-driven self-assembly endows the molecule with customized thermodynamically stable structures and desired properties. In this paper, a luminous metal-organic cage [Zn12L6] (S) was elaborately designed and quantitatively synthesized by self-assembly of tetrapodal TQPP chromophore-containing terpyridine ligand L with Zn2+. Complex S possessed a rigid cage-like structure, which endows a higher fluorescence quantum efficiency both in solution (∼88%) and neat solid (16%) than the corresponding ligand L. Further, using complex S as the photoactive component, two light-emitting diodes (LEDs) were successfully fabricated and the emission of pure white light (CIE coordinates: 0.3341, 0.3300) was achieved. These results afford a method to obtain enhanced luminescence performance via the formation of rigid coordination-driven supramolecular architectures.

20.
Cell Mol Biol (Noisy-le-grand) ; 70(8): 153-157, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39262248

RESUMO

To explore the impacts of intestinal flora on cerebral hemorrhage area and brain tissue inflammation in acute hemorrhagic stroke, seventy-two male C57BL/6 mice were randomly separated into 6 groups (n=12), the experimental group (EG, day 1, day 3 and day 7) and the control group (CG, day 1, day 3 and day 7). The mouse cerebral hemorrhage model was established by collagenase injection, and the EG received 0.4 mL fecal filtrate of healthy mice once a day, and the CG received the same amount of normal saline transplantation. The mNSS score, hematoma volume and cerebral edema content were used to evaluate nerve function injury and brain injury degree at each time point after operation. The expressions of inflammatory factors were detected by western blot. We found that at each time point after operation, compared with the CG, nerve function deficit scores of mice in the EG declined (P<0.05), the water content of mice brain tissue in the EG declined (P<0.05), and the protein expressions of inflammatory factors in the EG were decreased (P<0.05). Relative to the CG, the volume of hematoma in the EG declined on day 3 along with day 7 after operation (P<0.05). In conclusion, intestinal flora can reduce cerebral hemorrhage area and brain tissue inflammation, and then improve the performance of nerve function deficit in acute hemorrhagic stroke.


Assuntos
Encéfalo , Hemorragia Cerebral , Microbioma Gastrointestinal , Acidente Vascular Cerebral Hemorrágico , Camundongos Endogâmicos C57BL , Animais , Masculino , Hemorragia Cerebral/complicações , Hemorragia Cerebral/patologia , Hemorragia Cerebral/microbiologia , Hemorragia Cerebral/metabolismo , Acidente Vascular Cerebral Hemorrágico/patologia , Acidente Vascular Cerebral Hemorrágico/metabolismo , Encéfalo/patologia , Encéfalo/metabolismo , Inflamação/patologia , Inflamação/metabolismo , Modelos Animais de Doenças , Camundongos , Edema Encefálico/patologia , Edema Encefálico/metabolismo , Hematoma/patologia , Hematoma/metabolismo , Hematoma/complicações
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA