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In brief: Cordycepin (COR), a compound derived from Cordyceps, is recognized as an adenosine analog with numerous beneficial effects on human health. However, its impact on steroidogenic acute regulatory protein (STAR) expression in ovarian granulosa cells is not well understood. This study demonstrates that COR downregulates STAR expression by reducing the expression of the SP1 transcription factor. Abstract: Cordycepin (COR), a pure compound of Cordyceps, is known as an adenosine analog that exerts many beneficial effects on human health. The steroidogenesis mediated by ovarian granulosa cells is pivotal in maintaining normal female reproductive function. The steroidogenic acute regulatory protein (STAR) regulates the rate-limiting step in steroidogenesis. COR has been shown to stimulate STAR expression in mouse Leydig cells, the steroidogenic cells in the testes. However, the effect of COR on STAR expression in ovarian granulosa cells remains undetermined. In the present study, we show that treatment with COR downregulates STAR expression in a steroidogenic human granulosa-like tumor cell line, KGN, and primary culture of human granulosa-lutein (hGL) cells obtained from patients undergoing in vitro fertilization. We used specific adenosine receptor (AR) antagonists, and our results reveal that the inhibitory effect of COR on STAR expression is mediated by AR-A1, AR-A2A, and AR-A3. In both KGN and primary hGL cells, COR activates ERK1/2 and AKT signaling pathways, but only activation of ERK1/2 is required for the COR-induced downregulation of STAR expression. In addition, our results demonstrate that COR downregulates STAR expression by reducing the expression of the SP1 transcription factor. These results provide a better understanding of the biological function of COR on STAR expression in the ovary, which may lead to the development of alternative therapeutic approaches for female reproductive disorders.
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Desoxiadenosinas , Células da Granulosa , Células Lúteas , Fosfoproteínas , Fator de Transcrição Sp1 , Feminino , Humanos , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genética , Desoxiadenosinas/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células Lúteas/efeitos dos fármacos , Células Lúteas/metabolismo , Receptor A1 de Adenosina/metabolismo , Receptor A1 de Adenosina/genética , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacosRESUMO
Alternatively activated M2 macrophages play an important role in maintenance of tissue homeostasis by scavenging dead cells, cell debris and lipoprotein aggregates via phagocytosis. Using proteomics, we investigated how alternative activation, driven by IL-4, modulated the phagosomal proteome to control macrophage function. Our data indicate that alternative activation enhances homeostatic functions such as proteolysis, lipolysis and nutrient transport. Intriguingly, we identified the enhanced recruitment of the TAK1/MKK7/JNK signalling complex to phagosomes of IL-4-activated macrophages. The recruitment of this signalling complex was mediated through K63 polyubiquitylation of the macrophage scavenger receptor 1 (MSR1). Triggering of MSR1 in IL-4-activated macrophages leads to enhanced JNK activation, thereby promoting a phenotypic switch from an anti-inflammatory to a pro-inflammatory state, which was abolished upon MSR1 deletion or JNK inhibition. Moreover, MSR1 K63 polyubiquitylation correlated with the activation of JNK signalling in ovarian cancer tissue from human patients, suggesting that it may be relevant for macrophage phenotypic shift in vivo Altogether, we identified that MSR1 signals through JNK via K63 polyubiquitylation and provides evidence for the receptor's involvement in macrophage polarization.
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Inflamação , Interleucina-4/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Ativação de Macrófagos , Receptores Depuradores Classe A/agonistas , Receptores Depuradores Classe A/genética , Animais , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/genética , Células Cultivadas , Feminino , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Lipólise/efeitos dos fármacos , Lipólise/genética , Lipoproteínas LDL/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/genética , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagocitose/efeitos dos fármacos , Fagocitose/genética , Polissacarídeos/farmacologia , Processamento de Proteína Pós-Traducional/genética , Células RAW 264.7 , Receptores Depuradores Classe A/química , Receptores Depuradores Classe A/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ubiquitinação/genéticaRESUMO
The type VII protein secretion system (T7SS) is conserved across Staphylococcus aureus strains and plays important roles in virulence and interbacterial competition. To date, only one T7SS substrate protein, encoded in a subset of S. aureus genomes, has been functionally characterized. Here, using an unbiased proteomic approach, we identify TspA as a further T7SS substrate. TspA is encoded distantly from the T7SS gene cluster and is found across all S. aureus strains as well as in Listeria and Enterococci. Heterologous expression of TspA from S. aureus strain RN6390 indicates its C-terminal domain is toxic when targeted to the Escherichia coli periplasm and that it depolarizes the cytoplasmic membrane. The membrane-depolarizing activity is alleviated by coproduction of the membrane-bound TsaI immunity protein, which is encoded adjacent to tspA on the S. aureus chromosome. Using a zebrafish hindbrain ventricle infection model, we demonstrate that the T7SS of strain RN6390 promotes bacterial replication in vivo, and deletion of tspA leads to increased bacterial clearance. The toxin domain of TspA is highly polymorphic and S. aureus strains encode multiple tsaI homologs at the tspA locus, suggestive of additional roles in intraspecies competition. In agreement, we demonstrate TspA-dependent growth inhibition of RN6390 by strain COL in the zebrafish infection model that is alleviated by the presence of TsaI homologs.
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Staphylococcus aureus/metabolismo , Sistemas de Secreção Tipo VII/metabolismo , Animais , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Proteínas de Membrana/metabolismo , Família Multigênica/genética , Transporte Proteico/genética , Proteômica , Infecções Estafilocócicas/microbiologia , Toxinas Biológicas/metabolismo , Sistemas de Secreção Tipo VII/fisiologia , Virulência/genética , Peixe-Zebra/microbiologiaRESUMO
BACKGROUND: TP53 is an important tumor suppressor gene on human 17th chromosome with its mutations more than 60% in tumor cells. Lung cancer is the highest incidence malignancy in men around the world. N-6 methylase (m6A) is an enzyme that plays an important role in mRNA splicing, translation, and stabilization. However, its role in TP53-mutant non-small-cell lung cancer (NSCLC) remains unknown. METHOD: First, we investigated 17 common m6A regulators' prognostic values in NSCLC. Then, after the establishment of risk signature, we explored the diagnostic value of m6A in TP53-mutant NSCLC. Finally, gene set enrichment analysis (GSEA), gene ontology (GO) enrichment analysis, and differential expression analysis were used to reveal the possible mechanism of m6A regulators affecting TP53-mutant NSCLC patients. RESULTS: Study showed that nine m6A regulators (YTHDC2, METTL14, FTO, METTL16, YTHDF1, HNRNPA2B1, RBM15, KIAA1429, and WTAP) were expressed differently between TP53-mutant and wild-type NSCLC (p < 0.05); and ALKBH5 and HNRNPA2B1 were associated with the prognostic of TP53-mutant patients. After construction of the risk signature combined ALKBH5 and HNRNPA2B1, we divided patients with TP53 mutations into high- and low-risk groups, and there was a significant survival difference between two groups. Finally, 338 differentially expression genes (DEGs) were found between high- and low-risk groups. GO enrichment analysis, PPI network, and GSEA enrichment analysis showed that m6A may affect the immune environment in extracellular and change the stability of mRNA. CONCLUSION: In conclusion, m6A regulators can be used as prognostic predictors in TP53-mutant patients.
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Metiltransferases/genética , Proteína Supressora de Tumor p53/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Biologia Computacional , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Metilação , Mutação/genética , PrognósticoRESUMO
BACKGROUND: Long non-coding RNAs (lncRNAs) have been verified to play fatal role in regulating the progression of lung adenocarcinoma (LUAD). Although lncRNAs play important role in regulating the autophagy of tumor cells, the function and molecular mechanism of LINC01559 in regulating lung cancer development remain to be elucidated. METHOD AND MATERIALS: In this study, we used bioinformatics to screen out autophagy-related lncRNAs from TCGA-LUAD repository. Then the least absolute shrinkage and selection operator (LASSO) regression was applied to establish the signature of autophagy-related lncRNAs so that clinical characteristics and survival in LUAD patients be evaluated. Finally, we selected the most significant differences lncRNA, LINC01559, to verify its function in regulating LUAD progression in vitro. RESULTS: We found high expression of LINC01559 indicates lymph node metastasis and poor prognosis. Besides, LINC01559 promotes lung cancer cell proliferation and migration in vitro, by enhancing autophagy signal pathway via sponging hsa-miR-1343-3p. CONCLUSION: We revealed a novel prognostic model based on autophagy-related lncRNAs, and provide a new therapeutic target and for patients with lung adenocarcinoma named LINC01559.
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Recently, developing economical electrocatalysts with high performance in water decomposition has become a research hotspot. Herein, two kinds of cobalt-hybridized Cu3P nanostructure array electrocatalysts (including highly mesoporous 2D nanosheets and sugar gourd-like 1D nanowires) were controllably grown on a nickel foam substrate through a simple hydrothermal method combined with a subsequent phosphating treatment method. An electrocatalytic test indicated that the as-prepared 2D nanosheet array exhibited excellent activity and stability toward hydrogen evolution reaction under alkaline conditions, which offered a low overpotential of 99 mV at 10 mA/cm2 and a small Tafel slope of 70.4 mV/dec, whereas a competitive overpotential of 272 mV was required for oxygen evolution reaction. In addition, the 2D nanosheet array delivered a low cell voltage of 1.66 V at 10 mA/cm2 in a symmetric two-electrode system, implying its huge potential in overall water decomposition. The electrocatalytic performance is superior to the as-prepared 1D nanowire array and most of the Cu3P-related electrocatalysts previously reported. Experimental measurements and first-principles calculations show that the excellent performance of the 2D nanosheet array can be attributed to its unique 2D mesoporous structure and hybridization of cobalt, which not only provide a large electrochemically active surface and fast electrocatalytic reaction kinetics but also weaken the binding strength of electrocatalytic reaction intermediates. The present study provides a simple and controllable approach to synthesize Cu3P-based bimetallic phosphide nanostructures, which can be used as boosting Janus electrocatalysts for water decomposition.
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As the core of an electrocatalyst, the active site is critical to determine its catalytic performance in the hydrogen evolution reaction (HER). In this work, porous N-doped carbon-encapsulated CoP nanoparticles on both sides of graphene (CoP@NC/GR) are derived from a bimetallic metal-organic framework (MOF)@graphene oxide composite. Through active site engineering by tailoring the environment around CoP and engineering the structure, the HER activity of CoP@NC/GR heterostructures is significantly enhanced. Both X-ray photoelectron spectroscopy (XPS) results and density functional theory (DFT) calculations manifest that the electronic structure of CoP can be modulated by the carbon matrix of NC/GR, resulting in electron redistribution and a reduction in the adsorption energy of hydrogen (ΔGH*) from -0.53 to 0.04 eV. By engineering the sandwich-like structure, active sites in CoP@NC/GR are further increased by optimizing the Zn/Co ratio in the bimetallic MOF. Benefiting from this active site engineering, the CoP@NC/GR electrocatalyst exhibits small overpotentials of 105 mV in 0.5 M H2SO4 (or 125 mV in 1 M KOH) to 10 mA cm-2, accelerated HER kinetics with a low Tafel slope of 47.5 mV dec-1, and remarkable structural and HER stability.
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A novel nonprecious Fe2O3 nanoparticle decorated NiO nanosheet (Fe2O3 NPs@NiO NSs) composite has been obtained by a rapid one-pot electrochemical exfoliation method and can be used as an efficient oxygen evolution reaction (OER) catalyst. In the nanocomposite, the Fe2O3 NPs are uniformly anchored on the ultrathin graphene-like NiO nanosheets. At the same time, we also studied the influence of the Fe/Ni molar ratio on the morphology and catalytic activity. The Fe2O3 NPs@NiO NSs nanocomposite possessed a high BET surface area (194.1 m2 g-1), which is very conducive to the charge/mass transfer of electrolyte ions and O2. Owing to the unique two-dimensional (2D) heterostructures and rational Fe content, the as-prepared Fe2O3 NPs@NiO NSs show high catalytic performance, a low overpotential at 10 mA cm-2 (221 mV), a small Tafel slope (53.4 mV dec-1), and 2000 cycle and 20 h long-term durability. The introduction of Fe2O3 NPs is beneficial to accelerating charge transport, increasing the electrochemically active surface area (ECSA), and thus improving the release of oxygen bubbles from the electrode surface.
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BACKGROUND: N-6 methylation (m6A) pushes forward an immense influence on the occurrence and development of lung adenocarcinoma (LUAD). However, the methylation on non-coding RNA in LUAD, especially long non-coding RNA (lncRNA), has not been received sufficient attention. METHODS: Spearman correlation analysis was used to screen lncRNA correlated with m6A regulators expression from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) repositories, respectively. Then, the least absolute shrinkage and selection operator (LASSO) was applied to build a risk signature consisting m6A-related lncRNA. Univariate and multivariate independent prognostic analysis were applied to evaluate the performance of signature in predicting patients' survival. Next, we applied Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analysis (GSEA) to conduct pathway enrichment analysis of 3344 different expression genes (DEGs). Finally, we set up a competing endogenous RNAs (ceRNA) network to this lncRNA. RESULTS: A total of 85 common lncRNAs were selected to acquire the components related to prognosis. The final risk signature established by LASSO regression contained 11 lncRNAs: ARHGEF26-AS1, COLCA1, CRNDE, DLGAP1-AS2, FENDRR, LINC00968, TMPO-AS1, TRG-AS1, MGC32805, RPARP-AS1, and TBX5-AS1. M6A-related lncRNA risk score could predict the prognostic of LUAD and was significantly associated with clinical pathological. And in the evaluation of lung adenocarcinoma tumor microenvironment (TME) by using ESTIMATE algorithm, we found a statistically significant correlation between risk score and stromal/immune cells. CONCLUSION: M6A-related lncRNA was a potential prognostic and therapy target for lung adenocarcinoma.
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Adenocarcinoma de Pulmão , Adenosina/análogos & derivados , Neoplasias Pulmonares , RNA Longo não Codificante , Microambiente Tumoral/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Adenosina/química , Adenosina/genética , Adenosina/metabolismo , Idoso , Biologia Computacional , Metilação de DNA/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/química , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transcriptoma/genéticaRESUMO
Numerous efforts in improving the hydrogen evolution reaction (HER) performance of transition metal dichalcogenides mostly focus on active sites exposing, vacancy engineering, and phase engineering. However, little room is left for improvement in these approaches. It should be noted that efficient electron transfer also plays a crucial role in catalytic activity. In this work, by employment of an external vertical magnetic field, ferromagnetic bowl-like MoS2 flakes can afford electrons transmitting easily from a glassy carbon electrode to active sites to drive HER, and thus perform magnetic HER enhancement. The ferromagnetic bowl-like MoS2 flakes with an external vertical magnetic field can provide a roughly doubled current density compared to that without an external vertical magnetic field at a constant overpotential of -150 mV. Our work may provide a new pathway to break the bottleneck for further improvement of HER performance and also paves the way to utilize the magnetic enhancement in widely catalytic application.
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BACKGROUND: Endometriosis is a gynaecological condition characterised by immune cell infiltration and distinct inflammatory signatures found in the peritoneal cavity. In this study, we aim to characterise the immune microenvironment in samples isolated from the peritoneal cavity in patients with endometriosis. METHODS: We applied mass cytometry (CyTOF), a recently developed multiparameter single-cell technique, in order to characterise and quantify the immune cells found in peritoneal fluid and peripheral blood from endometriosis and control patients. RESULTS: Our results demonstrate the presence of more than 40 different distinct immune cell types within the peritoneal cavity. This suggests that there is a complex and highly heterogeneous inflammatory microenvironment underpinning the pathology of endometriosis. Stratification by clinical disease stages reveals a dynamic spectrum of cell signatures suggesting that adaptations in the inflammatory system occur due to the severity of the disease. Notably, among the inflammatory microenvironment in peritoneal fluid (PF), the presence of CD69+ T cell subsets is increased in endometriosis when compared to control patient samples. On these CD69+ cells, the expression of markers associated with T cell function are reduced in PF samples compared to blood. Comparisons between CD69+ and CD69- populations reveal distinct phenotypes across peritoneal T cell lineages. Taken together, our results suggest that both the innate and the adaptive immune system play roles in endometriosis. CONCLUSIONS: This study provides a systematic characterisation of the specific immune environment in the peritoneal cavity and identifies cell immune signatures associated with endometriosis. Overall, our results provide novel insights into the specific cell phenotypes governing inflammation in patients with endometriosis. This prospective study offers a useful resource for understanding disease pathology and opportunities for identifying therapeutic targets.
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Líquido Ascítico/imunologia , Endometriose/imunologia , Líquido Ascítico/metabolismo , Líquido Ascítico/patologia , Endometriose/metabolismo , Endometriose/patologia , Feminino , Citometria de Fluxo , Humanos , Estudos Prospectivos , Linfócitos TRESUMO
The Type VI secretion system (T6SS) is widespread among bacterial pathogens and acts as an effective weapon against competitor bacteria and eukaryotic hosts by delivering toxic effector proteins directly into target cells. The T6SS utilises a bacteriophage-like contractile machinery to expel a puncturing device based on a tube of Hcp topped with a VgrG spike, which can be extended by a final tip from a PAAR domain-containing protein. Effector proteins are believed to be delivered by specifically associating with particular Hcp, VgrG or PAAR proteins, either covalently ('specialised') or non-covalently ('cargo' effectors). Here we used the T6SS of the opportunistic pathogen Serratia marcescens, together with integratecd genetic, proteomic and biochemical approaches, to elucidate the role of specific VgrG and PAAR homologues in T6SS function and effector specificity, revealing new aspects and unexpected subtleties in effector delivery by the T6SS. We identified effectors, both cargo and specialised, absolutely dependent on a particular VgrG for delivery to target cells, and discovered that other cargo effectors can show a preference for a particular VgrG. The presence of at least one PAAR protein was found to be essential for T6SS function, consistent with designation as a 'core' T6SS component. We showed that specific VgrG-PAAR combinations are required to assemble a functional T6SS and that the three distinct VgrG-PAAR assemblies in S. marcescens exhibit distinct effector specificity and efficiency. Unexpectedly, we discovered that two different PAAR-containing Rhs proteins can functionally pair with the same VgrG protein. Showing that accessory EagR proteins are involved in these interactions, native VgrG-Rhs-EagR complexes were isolated and specific interactions between EagR and cognate Rhs proteins identified. This study defines an essential yet flexible role for PAAR proteins in the T6SS and highlights the existence of distinct versions of the machinery with differential effector specificity and efficiency of target cell delivery.
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Proteínas de Bactérias/metabolismo , Serratia marcescens/patogenicidade , Sistemas de Secreção Tipo VI/metabolismo , Sequência de Aminoácidos , Cromatografia de Afinidade , Técnicas de Cocultura , Escherichia coli , Immunoblotting , Espectrometria de Massas , Proteômica , Serratia marcescens/metabolismoRESUMO
Macrophages operate at the forefront of innate immunity and their discrimination of foreign versus "self" particles is critical for a number of responses including efficient pathogen killing, antigen presentation, and cytokine induction. In order to efficiently destroy the particles and detect potential threats, macrophages express an array of receptors to sense and phagocytose prey particles. In this study, we accurately quantified a proteomic time-course of isolated phagosomes from murine bone marrow-derived macrophages induced by particles conjugated to seven different ligands representing pathogen-associated molecular patterns, immune opsonins or apoptotic cell markers. We identified a clear functional differentiation over the three timepoints and detected subtle differences between certain ligand-phagosomes, indicating that triggering of receptors through a single ligand type has mild, but distinct, effects on phagosome proteome and function. Moreover, our data shows that uptake of phosphatidylserine-coated beads induces an active repression of NF-κB immune responses upon Toll-like receptor (TLR)-activation by recruitment of anti-inflammatory regulators to the phagosome. This data shows for the first time a systematic time-course analysis of bone marrow-derived macrophages phagosomes and how phagosome fate is regulated by the receptors triggered for phagocytosis.
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Macrófagos/química , Fagocitose , Fagossomos/química , Proteoma/análise , Animais , Calreticulina/imunologia , Calreticulina/farmacologia , Proteínas do Sistema Complemento/farmacologia , Imunidade Inata , Imunoglobulina G/farmacologia , Ligantes , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Mananas/imunologia , Mananas/farmacologia , Camundongos , Microesferas , NF-kappa B/genética , NF-kappa B/imunologia , Proteínas Opsonizantes/imunologia , Proteínas Opsonizantes/farmacologia , Fagossomos/imunologia , Fosfatidilserinas/imunologia , Fosfatidilserinas/metabolismo , Mapeamento de Interação de Proteínas , Proteoma/genética , Proteoma/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologiaRESUMO
Macrophages are important immune cells operating at the forefront of innate immunity by taking up foreign particles and microbes through phagocytosis. The RAW 264.7 cell line is commonly used for experiments in the macrophage and phagocytosis field. However, little is known how its functions compare to primary macrophages. Here, we have performed an in-depth proteomics characterization of phagosomes from RAW 264.7 and bone marrow derived macrophages by quantifying more than 2500 phagosomal proteins. Our data indicate that there are significant differences for a large number of proteins including important receptors such as mannose receptor 1 and Siglec-1. Moreover, bone marrow derived macrophages phagosomes mature considerably faster by fusion with endosomes and the lysosome which we validated using fluorogenic phagocytic assays. We provide a valuable resource for researcher in the field and recommend careful use of the RAW 264.7 cell line when studying phagosome functions. All MS data have been deposited in the ProteomeXchange with identifier PXD001293 (http://proteomecentral.proteomexchange.org/dataset/PXD001293).
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Bases de Dados de Proteínas , Macrófagos/química , Fagossomos/química , Proteoma , Células RAW 264.7 , Animais , Células Cultivadas , Camundongos , Mapas de Interação de Proteínas , Proteoma/análise , Proteoma/química , Proteoma/classificação , Proteômica , Células RAW 264.7/química , Células RAW 264.7/citologiaRESUMO
It has recently become apparent that the Type VI secretion system (T6SS) is a complex macromolecular machine used by many bacterial species to inject effector proteins into eukaryotic or bacterial cells, with significant implications for virulence and interbacterial competition. "Antibacterial" T6SSs, such as the one elaborated by the opportunistic human pathogen, Serratia marcescens, confer on the secreting bacterium the ability to rapidly and efficiently kill rival bacteria. Identification of secreted substrates of the T6SS is critical to understanding its role and ability to kill other cells, but only a limited number of effectors have been reported so far. Here we report the successful use of label-free quantitative mass spectrometry to identify at least eleven substrates of the S. marcescens T6SS, including four novel effector proteins which are distinct from other T6SS-secreted proteins reported to date. These new effectors were confirmed as antibacterial toxins and self-protecting immunity proteins able to neutralize their cognate toxins were identified. The global secretomic study also unexpectedly revealed that protein phosphorylation-based post-translational regulation of the S. marcescens T6SS differs from that of the paradigm, H1-T6SS of Pseudomonas aeruginosa. Combined phosphoproteomic and genetic analyses demonstrated that conserved PpkA-dependent threonine phosphorylation of the T6SS structural component Fha is required for T6SS activation in S. marcescens and that the phosphatase PppA can reverse this modification. However, the signal and mechanism of PpkA activation is distinct from that observed previously and does not appear to require cell-cell contact. Hence this study has not only demonstrated that new and species-specific portfolios of antibacterial effectors are secreted by the T6SS, but also shown for the first time that PpkA-dependent post-translational regulation of the T6SS is tailored to fit the needs of different bacterial species.
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Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos/fisiologia , Toxinas Bacterianas/metabolismo , Serratia marcescens/metabolismo , Espectrometria de Massas , Fosfopeptídeos/metabolismo , ProteômicaRESUMO
A novel targeting drug carrier (FA-BO-PAMAM) based on the PAMAM G5 dendrimer modified with borneol (BO) and folic acid (FA) molecules on the periphery and doxorubicin (DOX) loaded in the interior was designed and prepared to achieve the purposes of enhancing the blood-brain barrier (BBB) transportation and improving the drug accumulation in the glioma cells. 1H NMR was used to confirm the synthesis of FA-BO-PAMAM; its morphology and mean size were analyzed by dynamic light scattering (DLS) and transmission electron microscope (TEM). Based on the HBMEC and C6 cells, cytotoxicity assay, transport across the BBB, cellular uptake and anti-tumor activity in vitro were investigated to evaluate the properties of nanocarriers in vitro. The results showed that the nanocarrier of FA-BO-PAMAM was successfully synthesized, which was spherical in morphology with the average size of (22.28 ± 0.42) nm, and zeta potential of (7.6 ± 0.89) mV. Cytotoxicity and transport across the BBB assay showed that BO-modified conjugates decreased the cytotoxicity of PAMAM against both HBMEC and C6 cells and exhibited higher BBB transportation ability than BO-unmodified conjugates; moreover, modification with FA increased the total uptake of DOX by C6 cells and enhanced the cytotoxicity of DOX-polymer against C6 cells. Therefore, FA-BO-PAMAM is a promising nanodrug delivery system in employing PAMAM as a drug carrier and treatment for brain glioma.
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Canfanos/química , Dendrímeros , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Ácido Fólico/química , Transporte Biológico , Barreira Hematoencefálica , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Glioma , HumanosRESUMO
In cocreating value with other organizations, nonprofit organizations may face multiple management challenges, posed by multistakeholder global innovation networks. Since these have not yet been systematically studied by academics, this study explores how nonprofit organizations can promote the cocreation of value in multistakeholder global innovation networks. Adopting a longitudinal single-case study approach from the perspective of network orchestration theory, this work deeply analyzes how nonprofit organizations can promote the evolution of the global innovation network of the COVID-19 vaccine under the COVAX program. The results show that nonprofits need to successively address the dilemmas of legitimacy, direction, and heterogeneity in constructing global innovation networks and that to solve these stage dilemmas, orchestrators must successively function as network architects, liaisons, and leaders to direct the implementation of network actions using trusted, leveraged, and adapted orchestration logics. This paper further proposes a model of the orchestration process and mechanisms by which nonprofit organizations facilitate multistakeholder global innovation networks. Theoretically, this study therefore extends network orchestration theory by summarizing the mechanisms and orchestration logics by which NPOs construct and develop networks when they act as orchestrators. From a practical perspective, this study also provides guidance for future unexpected global public health crises, improving the global community's ability to combat them.
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Dental implant surgery is a procedure that replaces damaged or missing teeth with an artificial implant. During this procedure, guided bone regeneration (GBR) membranes are commonly used to inhibit the migration of epithelium and GBR at the surgical sites. Due to its biodegradability, good biocompatibility, and unique biological properties, gelatin (GT) is considered a suitable candidate for guiding periodontal tissue regeneration. However, GT-based membranes come with limitations, such as poor mechanical strength and mismatched degradation rates. To confront this challenge, a series of GT/poly(4-hydroxybutyrate) (P4HB) composite membranes are fabricated through electrospinning technology. The morphology, composition, wetting properties, mechanical properties, biocompatibility, and in vivo biodegradability of the as-prepared composite membranes are carefully characterized. The results demonstrate that all the membranes present excellent biocompatibility. Moreover, the in vivo degradation rate of the membranes can be manipulated by changing the ratio of GT and P4HB. The results indicate that the optimized GT/P4HB membranes with a high P4HB content (75%) may be suitable for periodontal tissue engineering because of their good mechanical properties and biodegradation rate compatible with tissue growth.
Assuntos
Gelatina , Membranas Artificiais , Gelatina/química , Animais , Poliésteres/química , Poliésteres/farmacologia , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Engenharia Tecidual/métodos , Implantes AbsorvíveisRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Reflux esophagitis (RE) is a common chronic inflammatory disease of the esophageal mucosa with a high prevalence and recurrence rate, for which a satisfactory therapeutic strategy is still lacking. Chinese medicine has its characteristics and advantages in treating RE, and the clinical application of Xuanfu Daizhe Tang (XDT) in treating RE has achieved sound therapeutic effects. However, there needs to be more research on its mechanism of action. AIM OF THE STUDY: The present work aimed to investigate the mechanism of XDT action in RE through the Signal Transducer and Activator of Transcription 1 (STAT1)/Triggering Receptor Expressed on Myeloid cells-1 (TREM-1) pathway. MATERIALS AND METHODS: The main active components of XDT were analyzed by ultra-performance liquid chromatography-mass spectrometer (UPLC-MS). The effect of XDT on RE was evaluated in a rat model of RE induced by "Cardioplasty + pyloric ligation + Roux-en-Y esophagojejunostomy". Each administration group was treated by gavage. The degree of damage to the esophageal mucosa was evaluated by visual observation, and the Potential of Hydrogen (PH) method and Hematoxylin-eosin staining (HE) staining were performed. Serum levels of Interleukin-1ß (IL-1ß), Interleukin-6 (IL-6), Tumor Necrosis Factor alpha (TNF-α), and Inducible Nitric Oxide Synthase (iNOS) were measured by ELISA. Quantitative Real-time PCR (qPCR), Western Blot (WB), and Immunofluorescence (IF) methods were used to detect Claudin-4, Claudin-5, TREM-1, and p-STAT1 in esophageal tissues for studying the mechanism of action and signaling pathway of XDT. Immunohistochemistry (IHC) analysis was used to detect the expression of TREM-1 and CD68 in esophageal tissues. Flow Cytometry (FC) was used to detect the polarization of macrophages in the blood. After conducting preliminary experiments to verify our hypothesis, we performed molecular docking between the active component of XDT and STAT1 derived from rats and parallel experiments with STAT1 inhibitor. The selective increaser of STAT1 transcription (2-NP) group was used to validate the mechanism by which XDT acts. RESULTS: XDT alleviated esophageal injury and attenuated histopathological changes in RE rats. XDT also inhibited the inflammatory response and decreased serum IL-1ß, IL-6, TNF-α, and iNOS levels in RE rats. qPCR and WB results revealed that XDT inhibited the expression of Claudin-4, Claudin-5, TREM-1, and STAT1 in the esophageal mucosa of RE rats. IHC and FC results showed that XDT reduced TREM-1 levels in esophageal tissues and polarized macrophages toward M2. The molecular docking results showed that rat-derived STAT1 can strongly bind to Isochronogenic acid A in XDT. The parallel experimental results of STAT1 inhibitor showed that XDT has anti-inflammatory effects similar to STAT1 inhibitors. The 2-NP group confirmed that XDT exerts its therapeutic effect on reflux esophagitis through the STAT1/TREM-1 pathway, with STAT1 as the upstream protein. CONCLUSIONS: This study suggests that XDT may treat reflux esophagitis by modulating the STAT1/TREM-1 pathway.
Assuntos
Esofagite Péptica , Ratos , Animais , Esofagite Péptica/tratamento farmacológico , Esofagite Péptica/metabolismo , Esofagite Péptica/patologia , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa , Claudina-4 , Claudina-5 , Cromatografia Líquida , Simulação de Acoplamento Molecular , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Reflux esophagitis (RE) is a disease in which inflammation of the esophageal mucosa owing to the reflux of gastric contents into the esophagus results in cytokine damage. Britannilactone 1-O-acetate (Brt) has anti-inflammatory effects, significantly inhibiting the activation of the NLRP3 inflammasome, leading to a decrease in inflammatory factors including IL-1 ß, IL-6, and TNF-α. However, the mechanism underlying its protective effect against RE-induced esophageal injury remains unclear. In the present study, we investigated the protective mechanism of TRIM31 against NLRP3 ubiquitination-induced RE both in vivo and in vitro. METHODS: A model of RE was established in vivo in rats by the method of "4.2 mm pyloric clamp + 2/3 fundoplication". In vitro, the mod was constructed by using HET-1A (esophageal epithelial cells) and exposing the cells to acid, bile salts, and acidic bile salts. The 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay was used to screen the concentration of administered drugs, and the viability of HET-1A cells in each group. HE staining was used to assess the degree of pathological damage in esophageal tissues. Toluidine blue staining was used to detect whether the protective function of the esophageal epithelial barrier was damaged and restored. The enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of IL-1 ß, IL-6, and TNF-α factors in serum. Immunohistochemistry (IHC) was used to detect the expression level of NLRP3 in esophageal tissues. The molecular docking and Co-immunoprecipitation assay (Co-IP assay) were used to detect the TRIM31 interacts with NLRP3. Western blotting detected the Claudin-4, Claudin-5, The G-protein-coupled receptor calcium-sensitive receptor (CaSR), NLRP3, TRIM31, ASC, C-Caspase1, and Caspase1 protein expression levels. RESULTS: Brt could alleviate RE inflammatory responses by modulating serum levels of IL-1 ß, IL-6, and TNF-α. It also activated the expression of NLRP3, ASC, Caspase 1, and C-Caspase-1 in HET-1A cells. Brt also attenuated TRIM31/NLRP3-induced pathological injury in rats with RE through a molecular mechanism consistent with the in vitro results. CONCLUSIONS: Brt promotes the ubiquitination of NLRP3 through TRIM31 and attenuates esophageal epithelial damage induced by RE caused by acidic bile salt exposure. This study provides valuable insights into the mechanism of action of Brt in the treatment of RE and highlights its promising application in the prevention of NLRP3 inflammatory vesicle-associated inflammatory pathological injury.