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1.
Cell ; 176(1-2): 348-360.e12, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30595449

RESUMO

Natural killer (NK) cells develop from common progenitors but diverge into distinct subsets, which differ in cytokine production, cytotoxicity, homing, and memory traits. Given their promise in adoptive cell therapies for cancer, a deeper understanding of regulatory modules controlling clinically beneficial NK phenotypes is of high priority. We report integrated "-omics" analysis of human NK subsets, which revealed super-enhancers associated with gene cohorts that may coordinate NK functions and localization. A transcription factor-based regulatory scheme also emerged, which is evolutionarily conserved and shared by innate and adaptive lymphocytes. For both NK and T lineages, a TCF1-LEF1-MYC axis dominated the regulatory landscape of long-lived, proliferative subsets that traffic to lymph nodes. In contrast, effector populations circulating between blood and peripheral tissues shared a PRDM1-dominant landscape. This resource defines transcriptional modules, regulated by feedback loops, which may be leveraged to enhance phenotypes for NK cell-based therapies.


Assuntos
Células Matadoras Naturais/classificação , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/fisiologia , Citocinas/imunologia , Citocinas/metabolismo , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Humanos , Fenótipo
2.
Nat Immunol ; 22(4): 460-470, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33767425

RESUMO

Targeting the p53-MDM2 pathway to reactivate tumor p53 is a chemotherapeutic approach. However, the involvement of this pathway in CD8+ T cell-mediated antitumor immunity is unknown. Here, we report that mice with MDM2 deficiency in T cells exhibit accelerated tumor progression and a decrease in tumor-infiltrating CD8+ T cell survival and function. Mechanistically, MDM2 competes with c-Cbl for STAT5 binding, reduces c-Cbl-mediated STAT5 degradation and enhances STAT5 stability in tumor-infiltrating CD8+ T cells. Targeting the p53-MDM2 interaction with a pharmacological agent, APG-115, augmented MDM2 in T cells, thereby stabilizing STAT5, boosting T cell immunity and synergizing with cancer immunotherapy. Unexpectedly, these effects of APG-115 were dependent on p53 and MDM2 in T cells. Clinically, MDM2 abundance correlated with T cell function and interferon-γ signature in patients with cancer. Thus, the p53-MDM2 pathway controls T cell immunity, and targeting this pathway may treat patients with cancer regardless of tumor p53 status.


Assuntos
Linfócitos T CD8-Positivos/enzimologia , Linfócitos do Interstício Tumoral/enzimologia , Neoplasias/enzimologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fator de Transcrição STAT5/metabolismo , Animais , Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/transplante , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Estabilidade Proteica , Proteólise , Proteínas Proto-Oncogênicas c-mdm2/genética , Fator de Transcrição STAT5/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
3.
Mol Cell ; 81(6): 1216-1230.e9, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33606996

RESUMO

Interferon-γ (IFN-γ)-mediated adaptive resistance is one major barrier to improving immunotherapy in solid tumors. However, the mechanisms are not completely understood. Here, we report that IFN-γ promotes nuclear translocation and phase separation of YAP after anti-PD-1 therapy in tumor cells. Hydrophobic interactions of the YAP coiled-coil domain mediate droplet initiation, and weak interactions of the intrinsically disordered region in the C terminus promote droplet formation. YAP partitions with the transcription factor TEAD4, the histone acetyltransferase EP300, and Mediator1 and forms transcriptional hubs for maximizing target gene transcriptions, independent of the canonical STAT1-IRF1 transcription program. Disruption of YAP phase separation reduced tumor growth, enhanced immune response, and sensitized tumor cells to anti-PD-1 therapy. YAP activity is negatively correlated with patient outcome. Our study indicates that YAP mediates the IFN-γ pro-tumor effect through its nuclear phase separation and suggests that YAP can be used as a predictive biomarker and target of anti-PD-1 combination therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistencia a Medicamentos Antineoplásicos , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Interferon gama/metabolismo , Neoplasias Experimentais , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Células HEK293 , Humanos , Interferon gama/genética , Camundongos , Camundongos Knockout , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
4.
Nat Chem Biol ; 20(6): 710-720, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38200110

RESUMO

Biomolecular condensates have been proposed to mediate cellular signaling transduction. However, the mechanism and functional consequences of signal condensates are not well understood. Here we report that LATS2, the core kinase of the Hippo pathway, responds to F-actin cytoskeleton reduction and forms condensates. The proline-rich motif (PRM) of LATS2 mediates its condensation. LATS2 partitions with the main components of the Hippo pathway to assemble a signalosome for LATS2 activation and for its stability by physically compartmentalizing from E3 ligase FBXL16 complex-dependent degradation, which in turn mediates yes-associated protein (YAP)-transcriptional coactivator with PDZ-binding motif (TAZ) recruitment and inactivation. This oncogenic FBXL16 complex blocks LATS2 condensation by binding to the PRM region to promote its degradation. Disruption of LATS2 condensation leads to tumor progression. Thus, our study uncovers that the signalosomes assembled by LATS2 condensation provide a compartmentalized and reversible platform for Hippo signaling transduction and protein stability, which have potential implications in cancer diagnosis and therapeutics.


Assuntos
Via de Sinalização Hippo , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Proteínas Supressoras de Tumor , Proteínas Serina-Treonina Quinases/metabolismo , Humanos , Proteínas Supressoras de Tumor/metabolismo , Células HEK293 , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , Camundongos , Proteínas de Sinalização YAP/metabolismo , Fatores de Transcrição/metabolismo
5.
Nature ; 585(7824): 277-282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879489

RESUMO

Abnormal epigenetic patterns correlate with effector T cell malfunction in tumours1-4, but the cause of this link is unknown. Here we show that tumour cells disrupt methionine metabolism in CD8+ T cells, thereby lowering intracellular levels of methionine and the methyl donor S-adenosylmethionine (SAM) and resulting in loss of dimethylation at lysine 79 of histone H3 (H3K79me2). Loss of H3K79me2 led to low expression of STAT5 and impaired T cell immunity. Mechanistically, tumour cells avidly consumed methionine and outcompeted T cells for methionine by expressing high levels of the methionine transporter SLC43A2. Genetic and biochemical inhibition of tumour SLC43A2 restored H3K79me2 in T cells, thereby boosting spontaneous and checkpoint-induced tumour immunity. Moreover, methionine supplementation improved the expression of H3K79me2 and STAT5 in T cells, and this was accompanied by increased T cell immunity in tumour-bearing mice and patients with colon cancer. Clinically, tumour SLC43A2 correlated negatively with T cell histone methylation and functional gene signatures. Our results identify a mechanistic connection between methionine metabolism, histone patterns, and T cell immunity in the tumour microenvironment. Thus, cancer methionine consumption is an immune evasion mechanism, and targeting cancer methionine signalling may provide an immunotherapeutic approach.


Assuntos
Sistema L de Transporte de Aminoácidos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Histonas/metabolismo , Metionina/metabolismo , Metilação , Neoplasias/metabolismo , Sistema L de Transporte de Aminoácidos/deficiência , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Histonas/química , Humanos , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Transcrição STAT5/metabolismo
6.
Stem Cells ; 42(6): 540-553, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38393342

RESUMO

Exploring the mechanism of self-renewal and pluripotency maintenance of human embryonic stem cells (hESCs) is of great significance in basic research and clinical applications, but it has not been fully elucidated. Long non-coding RNAs (lncRNAs) have been shown to play a key role in the self-renewal and pluripotency maintenance of hESCs. We previously reported that the lncRNA ESRG, which is highly expressed in undifferentiated hESCs, can maintain the self-renewal and pluripotency of hPSCs. RNA pull-down mass spectrometry showed that ESRG could bind to other proteins, among which heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) attracted our attention. In this study, we showed that HNRNPA1 can maintain self-renewal and pluripotency of hESCs. ESRG bound to and stabilized HNRNPA1 protein through the ubiquitin-proteasome pathway. In addition, knockdown of ESRG or HNRNPA1 resulted in alternative splicing of TCF3, which originally and primarily encoded E12, to mainly encode E47 and inhibit CDH1 expression. HNRNPA1 could rescue the biological function changes of hESCs caused by ESRG knockdown or overexpression. Our results suggest that ESRG regulates the alternative splicing of TCF3 to affect CDH1 expression and maintain hESCs self-renewal and pluripotency by binding and stabilizing HNRNPA1 protein. This study lays a good foundation for exploring the new molecular regulatory mechanism by which ESRG maintains hESCs self-renewal and pluripotency.


Assuntos
Processamento Alternativo , Ribonucleoproteína Nuclear Heterogênea A1 , Células-Tronco Embrionárias Humanas , RNA Longo não Codificante , Humanos , Processamento Alternativo/genética , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Ribonucleoproteína Nuclear Heterogênea A1/genética , Autorrenovação Celular/genética , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Diferenciação Celular/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
7.
J Immunol ; 210(4): 442-458, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36602826

RESUMO

African swine fever is one of the most serious viral diseases that affects domestic and wild pigs. The causative agent, African swine fever virus (ASFV), has evolved sophisticated immune evasion mechanisms that target both innate and adaptive immune responses. However, the underlying molecular mechanisms have not been fully understood. Here, we report that ASFV E184L protein inhibits host innate immune response via targeting the stimulator of IFN genes (STING)-mediated signaling pathway in both human embryonic kidney HEK-293T cells and porcine pulmonary alveolar macrophages. E184L interacts with STING, impairing dimerization and oligomerization of STING but not affecting its puncta formation at the perinuclear region. Furthermore, E184L disrupts STING-TBK1-IRF3 complex formation, leading to inhibition of STING phosphorylation, and IRF3 dimerization and nuclear translocation. The 1-20 aa region in E184L is essential for E184L-STING interaction and blocking IL-1ß and type I IFN production. Deletion of E184L in ASFV considerably impairs antagonistic function of the virus in suppression of the STING-mediated antiviral response, an effect that is reversible by introduction of E184L. Importantly, the virulence of mutant ASFV lacking E184L is reduced in pigs compared with its parental virus due to induction of higher IFN production in vivo. Our findings indicate that ASFV E184L is an important antagonist of IFN signaling to evade host innate immune antiviral responses, which improves our understanding of immune evasion mechanisms of ASFV.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Animais , Humanos , Antivirais/metabolismo , Imunidade Inata , Suínos , Proteínas Virais , Replicação Viral , Proteínas de Membrana/metabolismo , Interferons/biossíntese
8.
J Mol Cell Cardiol ; 187: 51-64, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38171043

RESUMO

Senescence of vascular smooth muscle cells (VSMCs) is a key contributor to plaque vulnerability in atherosclerosis (AS), which is affected by endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production. However, the crosstalk between ER stress and ROS production in the pathogenesis of VSMC senescence remains to be elucidated. ER-associated degradation (ERAD) is a complex process that clears unfolded or misfolded proteins to maintain ER homeostasis. HRD1 is the major E3 ligase in mammalian ERAD machineries that catalyzes ubiquitin conjugation to the unfolded or misfolded proteins for degradation. Our results showed that HRD1 protein levels were reduced in human AS plaques and aortic roots from ApoE-/- mice fed with high-fat diet (HFD), along with the increased ER stress response. Exposure to cholesterol in VSMCs activated inflammatory signaling and induced senescence, while reduced HRD1 protein expression. CRISPR Cas9-mediated HRD1 knockout (KO) exacerbated cholesterol- and thapsigargin-induced cell senescence. Inhibiting ER stress with 4-PBA (4-Phenylbutyric acid) partially reversed the ROS production and cell senescence induced by HRD1 deficiency in VSMCs, suggesting that ER stress alone could be sufficient to induce ROS production and senescence in VSMCs. Besides, HRD1 deficiency led to mitochondrial dysfunction, and reducing ROS production from impaired mitochondria partly reversed HRD1 deficiency-induced cell senescence. Finally, we showed that the overexpression of HDR1 reversed cholesterol-induced ER stress, ROS production, and cellular senescence in VSMCs. Our findings indicate that HRD1 protects against senescence by maintaining ER homeostasis and mitochondrial functionality. Thus, targeting HRD1 function may help to mitigate VSMC senescence and prevent vascular aging related diseases. TRIAL REGISTRATION: A real-world study based on the discussion of primary and secondary prevention strategies for coronary heart disease, URL:https://www.clinicaltrials.gov, the trial registration number is [2022]-02-121-01.


Assuntos
Aterosclerose , Músculo Liso Vascular , Animais , Humanos , Camundongos , Aterosclerose/metabolismo , Senescência Celular , Estresse do Retículo Endoplasmático/fisiologia , Degradação Associada com o Retículo Endoplasmático , Mamíferos/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
9.
Curr Issues Mol Biol ; 46(6): 6284-6299, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921046

RESUMO

Dracocephalum moldavica is widely used as an ornamental, medicine, and perfume in industry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) is widely and accurately utilized for gene expression evaluations. Selecting optimal reference genes is essential for normalizing RT-qPCR results. However, the identification of suitable reference genes in D. moldavica has not been documented. A total of 12 reference genes in D. moldavica were identified by PEG6000 (15%) treatment under hypertonia conditions in different tissues (roots, stem, leaves, flower, seeds and sepal) and during three stages of flower development, then used to validate the expression stability. There were four algorithms (delta Ct, geNorm, NormFinder, and BestKeeper) used to analyze the stability. Finally, the RefFinder program was employed to evaluate the candidate reference genes' stability. The results showed that ACTIN, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and EF1α (elongation factor-1α) were stable reference genes under the PEG6000 treatment. Heat shock protein 70 (HSP70) was the most stable gene across different flower development stages. ADP-ribosylation factor (ARF) was the most stable gene in different tissues and total samples. This study provides reliable gene expression studies for future research in D. moldavica.

10.
Anal Chem ; 96(19): 7353-7359, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38690857

RESUMO

Accurate detection of multiple cardiovascular biomarkers is crucial for the timely screening of acute coronary syndrome (ACS) and differential diagnosis from acute aortic syndrome (AAS). Herein, an antibody microarray-based metal-enhanced fluorescence assay (AMMEFA) has been developed to quantitatively detect 7 cardiovascular biomarkers through the formation of a sandwich immunoassay on the poly(glycidyl methacrylate-co-2-hydroxyethyl methacrylate)-decorated GNR-modified slide (GNR@P(GMA-HEMA) slide). The AMMEFA exhibits high specificity and sensitivity, the linear ranges span 5 orders of magnitude, and the limits of detection (LODs) of cardiac troponin I (cTnI), heart-type fatty acid binding protein (H-FABP), C-reactive protein (CRP), copeptin, myoglobin, D-Dimer, and N-terminal pro-brain natriuretic peptide (NT-proBNP) reach 0.07, 0.2, 65.7, 0.6, 0.2, 8.3, and 0.3 pg mL-1, respectively. To demonstrate its practicability, the AMMEFA has been applied to quantitatively analyze 7 cardiovascular biomarkers in 140 clinical plasma samples. In addition, the expression levels of cardiovascular biomarkers were analyzed by the least absolute shrinkage and selector operator (LASSO) regression, and the area under receiver operator characteristic curves (AUCs) of healthy donors (HDs), ACS patients, and AAS patients are 0.99, 0.98, and 0.97, respectively.


Assuntos
Biomarcadores , Humanos , Biomarcadores/sangue , Biomarcadores/análise , Análise Serial de Proteínas/métodos , Limite de Detecção , Imunoensaio/métodos , Fluorescência
11.
Anal Chem ; 96(3): 1138-1146, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38165811

RESUMO

Fast-paced pharmaceutical process developments (e.g., high-throughput experimentation, directed evolution, and machine learning) involve the introduction of fast, sensitive, and accurate analytical assays using limited sample volumes. In recent years, acoustic droplet ejection (ADE) coupled with an open port interface has been invented as a sampling technology for mass spectrometry, providing high-throughput nanoliter analytical measurements directly from the standard microplates. Herein, we introduce an ADE-multiple reaction monitoring-mass spectrometry (ADE-MRM-MS) workflow to accelerate pharmaceutical process research and development (PR&D). This systematic workflow outlines the selection of MRM transitions and optimization of assay parameters in a data-driven manner using rapid measurements (1 sample/s). The synergy between ADE sampling and MRM analysis enables analytical assays with excellent sensitivity, selectivity, and speed for PR&D reaction screenings. This workflow was utilized to develop new ADE-MRM-MS assays guiding a variety of industrial processes, including (1) screening of Ni-based catalysts for C-N cross-coupling reaction at 1 Hz and (2) high-throughput regioisomer analysis-enabled enzyme library screening for peptide ligation reaction. ADE-MRM-MS assays were demonstrated to deliver accurate results that are comparable to conventional liquid chromatography (LC) experiments while providing >100-fold throughput enhancement.


Assuntos
Desenvolvimento de Medicamentos , Acústica , Espectrometria de Massas/métodos , Peptídeos , Fluxo de Trabalho
12.
Biochem Biophys Res Commun ; 692: 149330, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38048728

RESUMO

The transcriptional activation function of YAP in cancer development has been widely studied. However, the underlying regulatory mechanisms remain largely unknown. In this study, we found that EP300, one histone acetyltransferase, interacted with YAP and was recruited into the phase separated condensates of YAP. Transcriptomic analysis revealed substantial alterations in gene expression upon EP300 depletion, with downregulated genes associated with cancer progression and Hippo-YAP pathway. Notably, disruption of EP300 inhibited the transcriptional activation of YAP and reduced the binding of H3K27ac on YAP target oncogenes in Hippo pathway. Moreover, depletion of EP300 effectively inhibited YAP-driven tumor growth. Taken together, these results indicate that EP300 contributes to lung cancer progression by promoting the oncogenic transcription of YAP through H3K27ac, which suggests that YAP-EP300 axis may be potential therapeutic targets for lung cancer treatment.


Assuntos
Via de Sinalização Hippo , Neoplasias Pulmonares , Humanos , Fatores de Transcrição/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias Pulmonares/genética , Proteínas de Sinalização YAP , Proliferação de Células , Linhagem Celular Tumoral , Proteína p300 Associada a E1A/metabolismo
13.
J Comput Chem ; 45(20): 1737-1743, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38622788

RESUMO

We present a comprehensive investigation of the electronic properties of fluorinated monolayer violet phosphorus using first-principles calculations. Our results reveal a strong dependence of the electronic properties on the different fluorine coverages of fluorination. As the fluorine coverage increases, monolayer violet phosphorus undergoes a significant transition from a wide direct bandgap semiconductor to a narrow indirect bandgap semiconductor. Moreover, both semi-fluorinated and fully fluorinated monolayer violet phosphorus exhibit advantageous semiconducting characteristics, with a tunable bandgap of 0.50 ~ 1.04 eV under biaxial strain ranging from -6% to 6%. Notably, the fully fluorinated monolayer violet phosphorus demonstrates a higher coefficient of light absorption within the visible range. Therefore, our findings highlight the tunability of monolayer violet phosphorus properties through the absorption of various fluorine coverages, providing valuable insights for the design and development of novel semiconductor devices based on this material.

14.
PLoS Pathog ; 18(3): e1010390, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35286345

RESUMO

[This corrects the article DOI: 10.1371/journal.ppat.1004253.].

15.
Cell Commun Signal ; 22(1): 275, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755602

RESUMO

BACKGROUND: Diabetic retinopathy (DR) is a major cause of blindness and is characterized by dysfunction of the retinal microvasculature. Neutrophil stasis, resulting in retinal inflammation and the occlusion of retinal microvessels, is a key mechanism driving DR. These plugging neutrophils subsequently release neutrophil extracellular traps (NETs), which further disrupts the retinal vasculature. Nevertheless, the primary catalyst for NETs extrusion in the retinal microenvironment under diabetic conditions remains unidentified. In recent studies, cellular communication network factor 1 (CCN1) has emerged as a central molecule modulating inflammation in pathological settings. Additionally, our previous research has shed light on the pathogenic role of CCN1 in maintaining endothelial integrity. However, the precise role of CCN1 in microvascular occlusion and its potential interaction with neutrophils in diabetic retinopathy have not yet been investigated. METHODS: We first examined the circulating level of CCN1 and NETs in our study cohort and analyzed related clinical parameters. To further evaluate the effects of CCN1 in vivo, we used recombinant CCN1 protein and CCN1 overexpression for gain-of-function, and CCN1 knockdown for loss-of-function by intravitreal injection in diabetic mice. The underlying mechanisms were further validated on human and mouse primary neutrophils and dHL60 cells. RESULTS: We detected increases in CCN1 and neutrophil elastase in the plasma of DR patients and the retinas of diabetic mice. CCN1 gain-of-function in the retina resulted in neutrophil stasis, NETs extrusion, capillary degeneration, and retinal leakage. Pre-treatment with DNase I to reduce NETs effectively eliminated CCN1-induced retinal leakage. Notably, both CCN1 knockdown and DNase I treatment rescued the retinal leakage in the context of diabetes. In vitro, CCN1 promoted adherence, migration, and NETs extrusion of neutrophils. CONCLUSION: In this study, we uncover that CCN1 contributed to retinal inflammation, vessel occlusion and leakage by recruiting neutrophils and triggering NETs extrusion under diabetic conditions. Notably, manipulating CCN1 was able to hold therapeutic promise for the treatment of diabetic retinopathy.


Assuntos
Proteína Rica em Cisteína 61 , Retinopatia Diabética , Armadilhas Extracelulares , Camundongos Endogâmicos C57BL , Neutrófilos , Retinopatia Diabética/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/genética , Armadilhas Extracelulares/metabolismo , Animais , Neutrófilos/metabolismo , Humanos , Proteína Rica em Cisteína 61/metabolismo , Proteína Rica em Cisteína 61/genética , Camundongos , Masculino , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações , Retina/patologia , Retina/metabolismo , Feminino , Pessoa de Meia-Idade
16.
Inorg Chem ; 63(2): 1274-1287, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38165643

RESUMO

A series of Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors were successfully prepared by the high-temperature solid-phase method. The phase and morphology of the phosphors were studied by means of Rietveld refinement and scanning electron microscopy. The results show that the phase is pure, and the crystal structure is the Ia3̅d space group. In the Ca3Al2Ge3O12: xDy3+ phosphors, using 380 nm excitation, phosphors showed blue (4F9/2 → 6H15/2) and yellow (4F9/2 → 6H13/2) emission peaks at 481 and 581 nm, respectively. In Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors, the energy transfer was inferred by the spectrum overlap of Dy3+ and Eu3+, and the lifetime attenuation was analyzed from the perspective of dynamics; finally, the band gap structure of the phosphors was analyzed by combining diffuse reflection spectra with the first principle, and the energy transfer mechanism and luminescence mechanism were elaborated by combining theory and practice. The transition from blue white light to red light can be achieved by tuning the range of y in Ca3Al2Ge3O12: 0.015Dy3+, yEu3+. Wherein, when y = 0.07, phosphors, the chromaticity coordinate of warm white CIE is (0.3932, 0.3203), the color temperature is 3093 K, and the warm white light is synthesized. The thermal stability of the synthesized warm white phosphors is 90.1% (423 K), the thermal sensing factors are Samax = 5.51 × 10-4 K-1 (303 K) and Srmax = 0.0359% K-1 (303 K), and the actual quantum efficiency is IQE = 52.48%. These results prove that Ca3Al2Ge3O12: Dy3+, Eu3+ have good application prospects as single-component warm w-LED devices.

17.
Phys Chem Chem Phys ; 26(4): 3375-3388, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38204322

RESUMO

LiYGeO4 phosphors doped with Dy3+ and Eu3+ ions were synthesized using the solid phase method, and their color characteristics were adjustable. The bandgap value of LiYGeO4 calculated by diffuse reflection data is very close to the theoretical value of 3.669 eV, indicating that LiYGeO4 is an ideal candidate for doped rare earth activated ions. The analysis of the emission spectra and fluorescence attenuation curves of Dy3+ and Eu3+ co-doped LiYGeO4 phosphors revealed a clear energy transfer process: energy transfer from Dy3+ to Eu3+. Analysis of emission spectra and fluorescence attenuation curves revealed a transfer of energy from Dy3+ to Eu3+. This transfer mechanism is attributed to the dipole-dipole interactions. In addition, by constantly adjusting the doping levels of Dy3+ and Eu3+, a warm white phosphor with a color temperature of 3881 K was obtained. Finally, the emission intensity of the LiYGeO4:0.015Dy3+,0.02Eu3+ phosphor at 423 K was 86%, indicating that the phosphor has excellent thermal stability and 40% internal quantum efficiency, which proves the potential application of the LiYGeO4 phosphor in white light-emitting diodes (w-LEDs).

18.
J Nat Prod ; 87(4): 1059-1066, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38561238

RESUMO

Seven new sugar alcohol-conjugated acyclic sesquiterpenes, acremosides A-G (1-7), were isolated from the cultures of the sponge-associated fungus Acremonium sp. IMB18-086 cultivated with heat-killed Pseudomonas aeruginosa. The structures were determined by comprehensive analyses of 1D and 2D NMR spectroscopic data. The relative configurations were established by J-based configuration analysis and acetonide derivatization. The absolute configurations were elucidated by the Mosher ester method and ECD calculations. The structures of acremosides E-G (5-7) featured the linear sesquiterpene skeleton with a tetrahydrofuran moiety attached to a sugar alcohol. Acremosides A (1) and C-E (3-5) showed significant inhibitory activities against hepatitis C virus (EC50 values of 4.8-8.8 µM) with no cytotoxicity (CC50 of >200 µM).


Assuntos
Acremonium , Sesquiterpenos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Animais , Estrutura Molecular , Acremonium/química , Antivirais/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Poríferos/química , Hepacivirus/efeitos dos fármacos , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos
19.
J Nat Prod ; 87(2): 365-370, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38276888

RESUMO

Violaceotides B-E (1-4), four new cyclic tetrapeptides, along with seven known compounds, were identified from the sponge-associated Aspergillus insulicola IMB18-072 co-cultivated with the marine-derived Alternaria angustiovoidea IMB20-805. Their structures were elucidated by extensive analysis of spectroscopic data, including HRESIMS, 1D and 2D NMR, and MS/MS data. The absolute configurations were determined by the advanced Marfey's method. Compounds 2, 3, and violaceotide A (5) displayed selective antimicrobial activities against the aquatic pathogenic bacteria Edwardsiella tarda and E. ictaluri. In addition, compounds 1-5 showed inhibitory activities against the LPS-induced expression of the inflammatory mediator IL-6 in RAW264.7 cells at a concentration of 10 µM.


Assuntos
Anti-Infecciosos , Espectrometria de Massas em Tandem , Técnicas de Cocultura , Espectroscopia de Ressonância Magnética , Anti-Inflamatórios/farmacologia , Estrutura Molecular , Fungos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química
20.
Cereb Cortex ; 33(24): 11517-11525, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-37851854

RESUMO

Speech and language processing involve complex interactions between cortical areas necessary for articulatory movements and auditory perception and a range of areas through which these are connected and interact. Despite their fundamental importance, the precise mechanisms underlying these processes are not fully elucidated. We measured BOLD signals from normal hearing participants using high-field 7 Tesla fMRI with 1-mm isotropic voxel resolution. The subjects performed 2 speech perception tasks (discrimination and classification) and a speech production task during the scan. By employing univariate and multivariate pattern analyses, we identified the neural signatures associated with speech production and perception. The left precentral, premotor, and inferior frontal cortex regions showed significant activations that correlated with phoneme category variability during perceptual discrimination tasks. In addition, the perceived sound categories could be decoded from signals in a region of interest defined based on activation related to production task. The results support the hypothesis that articulatory motor networks in the left hemisphere, typically associated with speech production, may also play a critical role in the perceptual categorization of syllables. The study provides valuable insights into the intricate neural mechanisms that underlie speech processing.


Assuntos
Percepção da Fala , Fala , Humanos , Fala/fisiologia , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Percepção Auditiva/fisiologia , Percepção da Fala/fisiologia
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