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1.
Immunity ; 52(2): 357-373.e9, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32049051

RESUMO

Clearance of apoptotic cells by macrophages prevents excessive inflammation and supports immune tolerance. Here, we examined the effect of blocking apoptotic cell clearance on anti-tumor immune response. We generated an antibody that selectively inhibited efferocytosis by phagocytic receptor MerTK. Blockade of MerTK resulted in accumulation of apoptotic cells within tumors and triggered a type I interferon response. Treatment of tumor-bearing mice with anti-MerTK antibody stimulated T cell activation and synergized with anti-PD-1 or anti-PD-L1 therapy. The anti-tumor effect induced by anti-MerTK treatment was lost in Stinggt/gt mice, but not in Cgas-/- mice. Abolishing cGAMP production in Cgas-/- tumor cells, depletion of extracellular ATP, or inactivation of the ATP-gated P2X7R channel also compromised the effects of MerTK blockade. Mechanistically, extracellular ATP acted via P2X7R to enhance the transport of extracellular cGAMP into macrophages and subsequent STING activation. Thus, MerTK blockade increases tumor immunogenicity and potentiates anti-tumor immunity, which has implications for cancer immunotherapy.


Assuntos
Macrófagos/imunologia , Proteínas de Membrana/metabolismo , Neoplasias/imunologia , Nucleotídeos Cíclicos/metabolismo , Receptores Purinérgicos P2X7/metabolismo , c-Mer Tirosina Quinase/imunologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Antígeno B7-H1/imunologia , Células Cultivadas , Feminino , Imunidade Inata , Imunoterapia , Interferon Tipo I/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Nucleotidiltransferases/deficiência , Nucleotidiltransferases/metabolismo , Fagocitose , Receptor de Morte Celular Programada 1/imunologia , Receptores Purinérgicos P2X7/deficiência , Transdução de Sinais/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , c-Mer Tirosina Quinase/genética
2.
Plant Cell ; 35(1): 453-468, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36190337

RESUMO

RAC/Rho of plant (ROP) GTPases are major molecular switches that control diverse signaling cascades for plant growth, development, and defense. Here, we discovered a signaling node that connects RAC/ROPs to cytokinins. Rice (Oryza sativa) plants develop a fibrous root system mainly composed of crown roots. Cytokinin signaling via a phosphorelay system is critical for crown root development. We show that OsRopGEF10, which activates RAC/ROPs, acts upstream of the cytoplasmic-nuclear shuttling phosphotransfer proteins AHPs of the cytokinin signaling pathway to promote crown root development. Mutations of OsRopGEF10 induced hypersensitivity to cytokinin, whereas overexpressing this gene reduced the cytokinin response. Loss of OsRopGEF10 function reduced the expression of the response regulator gene OsRR6, a repressor of cytokinin signaling, and impaired crown root development. Mutations in OsAHP1/2 led to increased crown root production and rescued the crown root defect of Osropgef10. Furthermore, auxin activates the ROP GTPase OsRAC3, which attenuates cytokinin signaling for crown root initiation. Molecular interactions between OsRopGEF10, OsRAC3, and OsAHP1/2 implicate a mechanism whereby OsRopGEF10-activated OsRAC3 recruits OsAHP1/2 to the cortical cytoplasm, sequestering them from their phosphorelay function in the nucleus. Together, our findings uncover the OsRopGEF10-OsRAC3-OsAHP1/2 signaling module, establish a link between RAC/ROPs and cytokinin, and reveal molecular crosstalk between auxin and cytokinin during crown root development.


Assuntos
Oryza , Oryza/metabolismo , Ativadores de GTP Fosfo-Hidrolase/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Transdução de Sinais , Citocininas/metabolismo , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas
3.
J Immunol ; 212(12): 1877-1890, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38700398

RESUMO

Despite the advances in study on osmotic physiology in bony fish, the mechanism by which the immune system, especially T-cell immunity, adapts and responds to osmotic stress remains unknown. In the current study, we investigated the response of T cells to hyperosmotic stress in the bony fish Nile tilapia (Oreochromis niloticus). As a euryhaline fish, tilapia was able to adapt to a wide range of salinities; however, hypertonic stress caused inflammation and excessive T-cell activation. Furthermore, hypertonic stress increased the expression of IL-17A in T cells, upregulated the transcription factor RORα, and activated STAT3 signaling, along with IL-6- and TGF-ß1-mediated pathways, revealing an enhanced Th17 response in this early vertebrate. These hypertonic stress-induced events collectively resulted in an impaired antibacterial immune response in tilapia. Hypertonic stress elevated the intracellular ROS level, which in turn activated the p38-MK2 signaling pathway to promote IL-17A production by T cells. Both ROS elimination and the p38-MK2 axis blockade diminished the increased IL-17A production in T cells under hypertonic conditions. Moreover, the produced proinflammatory cytokines further amplified the hypertonic stress signaling via the MKK6-p38-MK2 axis-mediated positive feedback loop. To our knowledge, these findings represent the first description of the mechanism by which T-cell immunity responds to hypertonic stress in early vertebrates, thus providing a novel perspective for understanding the adaptive evolution of T cells under environmental stress.


Assuntos
Inflamação , Pressão Osmótica , Células Th17 , Tilápia , Animais , Células Th17/imunologia , Inflamação/imunologia , Tilápia/imunologia , Transdução de Sinais/imunologia , Ativação Linfocitária/imunologia , Interleucina-17/metabolismo , Interleucina-17/imunologia
4.
Mol Cell ; 71(6): 1092-1104.e5, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30174291

RESUMO

Activation of class I phosphatidylinositol 3-kinase (PI3K) leads to formation of phosphatidylinositol-3,4,5-trisphophate (PIP3) and phosphatidylinositol-3,4-bisphophate (PI34P2), which spatiotemporally coordinate and regulate a myriad of cellular processes. By simultaneous quantitative imaging of PIP3 and PI34P2 in live cells, we here show that they have a distinctively different spatiotemporal distribution and history in response to growth factor stimulation, which allows them to selectively induce the membrane recruitment and activation of Akt isoforms. PI34P2 selectively activates Akt2 at both the plasma membrane and early endosomes, whereas PIP3 selectively stimulates Akt1 and Akt3 exclusively at the plasma membrane. These spatiotemporally distinct activation patterns of Akt isoforms provide a mechanism for their differential regulation of downstream signaling molecules. Collectively, our studies show that different spatiotemporal dynamics of PIP3 and PI34P2 and their ability to selectively activate key signaling proteins allow them to mediate class I PI3K signaling pathways in a spatiotemporally specific manner.


Assuntos
Imagem Óptica/métodos , Fosfatos de Fosfatidilinositol/fisiologia , Imagem Individual de Molécula/métodos , Animais , Linhagem Celular , Membrana Celular , Humanos , Fosfatos de Inositol , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Fosfatos de Fosfatidilinositol/metabolismo , Fosfatidilinositóis , Isoformas de Proteínas , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
5.
Nucleic Acids Res ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119921

RESUMO

Tn3 family transposons are a widespread group of replicative transposons, notorious for contributing to the dissemination of antibiotic resistance, particularly the global prevalence of carbapenem resistance. The transposase (TnpA) of these elements catalyzes DNA breakage and rejoining reactions required for transposition. However, the molecular mechanism for target site selection with these elements remains unclear. Here, we identify a QLxxLR motif in N-terminal of Tn3 TnpAs and demonstrate that this motif allows interaction between TnpA of Tn3 family transposon Tn1721 and the host ß-sliding clamp (DnaN), the major processivity factor of the DNA replication machinery. The TnpA-DnaN interaction is essential for Tn1721 transposition. Our work unveils a mechanism whereby Tn3 family transposons can bias transposition into certain replisomes through an interaction with the host replication machinery. This study further expands the diversity of mobile elements that use interaction with the host replication machinery to bias integration.

6.
Proc Natl Acad Sci U S A ; 120(4): e2212227120, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36652475

RESUMO

Propagating spatiotemporal neural patterns are widely evident across sensory, motor, and association cortical areas. However, it remains unclear whether any characteristics of neural propagation carry information about specific behavioral details. Here, we provide the first evidence for a link between the direction of cortical propagation and specific behavioral features of an upcoming movement on a trial-by-trial basis. We recorded local field potentials (LFPs) from multielectrode arrays implanted in the primary motor cortex of two rhesus macaque monkeys while they performed a 2D reach task. Propagating patterns were extracted from the information-rich high-gamma band (200 to 400 Hz) envelopes in the LFP amplitude. We found that the exact direction of propagating patterns varied systematically according to initial movement direction, enabling kinematic predictions. Furthermore, characteristics of these propagation patterns provided additional predictive capability beyond the LFP amplitude themselves, which suggests the value of including mesoscopic spatiotemporal characteristics in refining brain-machine interfaces.


Assuntos
Interfaces Cérebro-Computador , Córtex Motor , Animais , Macaca mulatta , Fenômenos Biomecânicos , Movimento , Potenciais de Ação
7.
J Immunol ; 210(8): 1166-1176, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881873

RESUMO

Efferocytosis is a phagocytic process by which apoptotic cells are cleared by professional and nonprofessional phagocytic cells. In tumors, efferocytosis of apoptotic cancer cells by tumor-associated macrophages prevents Ag presentation and suppresses the host immune response against the tumor. Therefore, reactivating the immune response by blockade of tumor-associated macrophage-mediated efferocytosis is an attractive strategy for cancer immunotherapy. Even though several methods have been developed to monitor efferocytosis, an automated and high-throughput quantitative assay should offer highly desirable advantages for drug discovery. In this study, we describe a real-time efferocytosis assay with an imaging system for live-cell analysis. Using this assay, we successfully discovered potent anti-MerTK Abs that block tumor-associated macrophage-mediated efferocytosis in mice. Furthermore, we used primary human and cynomolgus monkey macrophages to identify and characterize anti-MerTK Abs for potential clinical development. By studying the phagocytic activities of different types of macrophages, we demonstrated that our efferocytosis assay is robust for screening and characterization of drug candidates that inhibit unwanted efferocytosis. Moreover, our assay is also applicable to investigating the kinetics and molecular mechanisms of efferocytosis/phagocytosis.


Assuntos
Apoptose , Neoplasias , Camundongos , Humanos , Animais , c-Mer Tirosina Quinase , Macaca fascicularis , Fagocitose , Macrófagos , Neoplasias/patologia
8.
J Immunol ; 210(3): 229-244, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36548476

RESUMO

The braking mechanisms to protect the host from tissue damage and inflammatory disease caused by an overexuberant immune response are common in many T cell subsets. However, the negative regulation of T cell responses and detailed mechanisms are not well understood in early vertebrates. In the current study, using a Nile tilapia (Oreochromis niloticus) model, we investigated the suppression of T cell immunity by IL-10. Tilapia encodes an evolutionarily conserved IL-10, whose expression in lymphocytes is markedly induced during the primary adaptive immune response against Aeromonas hydrophila infection. Activated T cells of tilapia produce IL-10, which in turn inhibits proinflammatory cytokine expression and suppresses PHA-induced T cell activation. Moreover, administration of IL-10 impairs the proliferation of tilapia T cells, reduces their potential to differentiate into Th subsets, and cripples the cytotoxic function, rendering the animals more vulnerable to pathogen attack. After binding to its receptor IL-10Ra, IL-10 activates the JAK1/STAT3 axis by phosphorylation and enhances the expression of the suppressor of cytokine signaling 3 (SOCS3), which in turn attenuates the activation of the NF-κB and MAPK/ERK signaling pathways, thus suppressing the T cell response of tilapia. Our findings elucidate a negative regulatory mechanism of T cell immunity in a fish species and support the notion that the braking mechanism of T cells executed through IL-10 existed prior to the divergence of the tetrapod lineage from teleosts. Therefore, this study, to our knowledge, provides a novel perspective on the evolution of the adaptive immune system.


Assuntos
Ciclídeos , Doenças dos Peixes , Tilápia , Animais , NF-kappa B/metabolismo , Tilápia/metabolismo , Interleucina-10/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Proteínas de Peixes/metabolismo
9.
J Neurosci ; 43(21): 3807-3824, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37185099

RESUMO

Sphingosine-1-phosphate (S1P), a bioactive sphingolipid concentrated in the brain, is essential for normal brain functions, such as learning and memory and feeding behaviors. Sphingosine kinase 1 (SphK1), the primary kinase responsible for S1P production in the brain, is abundant within presynaptic terminals, indicating a potential role of the SphK1/S1P axis in presynaptic physiology. Altered S1P levels have been highlighted in many neurologic diseases with endocytic malfunctions. However, it remains unknown whether the SphK1/S1P axis may regulate synaptic vesicle endocytosis in neurons. The present study evaluates potential functions of the SphK1/S1P axis in synaptic vesicle endocytosis by determining effects of a dominant negative catalytically inactive SphK1. Our data for the first time identify a critical role of the SphK1/S1P axis in endocytosis in both neuroendocrine chromaffin cells and neurons from mice of both sexes. Furthermore, our Ca2+ imaging data indicate that the SphK1/S1P axis may be important for presynaptic Ca2+ increases during prolonged stimulations by regulating the Ca2+ permeable TRPC5 channels, which per se regulate synaptic vesicle endocytosis. Collectively, our data point out a critical role of the regulation of TRPC5 by the SphK1/S1P axis in synaptic vesicle endocytosis.SIGNIFICANCE STATEMENT Sphingosine kinase 1 (SphK1), the primary kinase responsible for brain sphingosine-1-phosphate (S1P) production, is abundant within presynaptic terminals. Altered SphK1/S1P metabolisms has been highlighted in many neurologic disorders with defective synaptic vesicle endocytosis. However, whether the SphK1/S1P axis may regulate synaptic vesicle endocytosis is unknown. Here, we identify that the SphK1/S1P axis regulates the kinetics of synaptic vesicle endocytosis in neurons, in addition to controlling fission-pore duration during single vesicle endocytosis in neuroendocrine chromaffin cells. The regulation of the SphK1/S1P axis in synaptic vesicle endocytosis is specific since it has a distinguished signaling pathway, which involves regulation of Ca2+ influx via TRPC5 channels. This discovery may provide novel mechanistic implications for the SphK1/S1P axis in brain functions under physiological and pathologic conditions.


Assuntos
Fosfotransferases (Aceptor do Grupo Álcool) , Vesículas Sinápticas , Masculino , Feminino , Camundongos , Animais , Vesículas Sinápticas/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Esfingosina/metabolismo , Endocitose , Lisofosfolipídeos/metabolismo , Canais de Cátion TRPC
10.
J Proteome Res ; 23(8): 3174-3187, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-38686625

RESUMO

NPC intracellular cholesterol transporter 1 (NPC1) is a multipass, transmembrane glycoprotein mostly recognized for its key role in facilitating cholesterol efflux. Mutations in the NPC1 gene result in Niemann-Pick disease, type C (NPC), a fatal, lysosomal storage disease. Due to the progressively expanding implications of NPC1-related disorders, we investigated endogenous NPC1 protein-protein interactions in the mouse cortex and human-derived iPSCs neuronal models of the disease through coimmunoprecipitation-coupled with LC-MS based proteomics. The current study investigated protein-protein interactions specific to the wild-type and the most prevalent NPC1 mutation (NPC1I1061T) while filtering out any protein interactor identified in the Npc1-/- mouse model. Additionally, the results were matched across the two species to map the parallel interactome of wild-type and mutant NPC1I1061T. Most of the identified wild-type NPC1 interactors were related to cytoskeleton organization, synaptic vesicle activity, and translation. We found many putative NPC1 interactors not previously reported, including two SCAR/WAVE complex proteins that regulate ARP 2/3 complex actin nucleation and multiple membrane proteins important for neuronal activity at synapse. Moreover, we identified proteins important in trafficking specific to wild-type and mutant NPC1I1061T. Together, the findings are essential for a comprehensive understanding of NPC1 biological functions in addition to its classical role in sterol efflux.


Assuntos
Córtex Cerebral , Proteína C1 de Niemann-Pick , Mapas de Interação de Proteínas , Animais , Córtex Cerebral/metabolismo , Camundongos , Humanos , Proteômica/métodos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Doença de Niemann-Pick Tipo C/metabolismo , Doença de Niemann-Pick Tipo C/genética , Mutação , Camundongos Knockout , Colesterol/metabolismo , Neurônios/metabolismo
11.
J Cell Mol Med ; 28(3): e18073, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38063077

RESUMO

Diabetic kidney disease (DKD) can lead to accumulation of glucose upstream metabolites due to dysfunctional glycolysis. But the effects of accumulated glycolysis metabolites on podocytes in DKD remain unknown. The present study examined the effect of dihydroxyacetone phosphate (DHAP) on high glucose induced podocyte pyroptosis. By metabolomics, levels of DHAP, GAP, glucose-6-phosphate and fructose 1, 6-bisphosphate were significantly increased in glomeruli of db/db mice. Furthermore, the expression of LDHA and PKM2 were decreased. mRNA sequencing showed upregulation of pyroptosis-related genes (Nlrp3, Casp1, etc.). Targeted metabolomics demonstrated higher level of DHAP in HG-treated podocytes. In vitro, ALDOB expression in HG-treated podocytes was significantly increased. siALDOB-transfected podocytes showed less DHAP level, mTORC1 activation, reactive oxygen species (ROS) production, and pyroptosis, while overexpression of ALDOB had opposite effects. Furthermore, GAP had no effect on mTORC1 activation, and mTORC1 inhibitor rapamycin alleviated ROS production and pyroptosis in HG-stimulated podocytes. Our findings demonstrate that DHAP represents a critical metabolic product for pyroptosis in HG-stimulated podocytes through regulation of mTORC1 pathway. In addition, the results provide evidence that podocyte injury in DKD may be treated by reducing DHAP.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Podócitos , Camundongos , Animais , Nefropatias Diabéticas/metabolismo , Podócitos/metabolismo , Fosfato de Di-Hidroxiacetona/metabolismo , Fosfato de Di-Hidroxiacetona/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Piroptose , Glucose/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Diabetes Mellitus/metabolismo
12.
Cancer Sci ; 115(4): 1141-1153, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38287724

RESUMO

The indigenous microbial milieu within tumorous tissues exerts a pivotal influence on the genesis and advancement of gastric cancer (GC). This investigation scrutinizes the functions and molecular mechanisms attributed to Prevotella intermedia in the malignant evolution of GC. Isolation of P. intermedia from paired GC tissues was undertaken. Quantification of P. intermedia abundance in 102 tissues was accomplished using quantitative real-time PCR (qRT-PCR). Assessment of the biological effects of P. intermedia on GC cells was observed using culture medium supernatant. Furthermore, the protein profile of GC cells treated with tumor-derived P. intermedia was examined through label-free protein analysis. The functionality of perilipin 3 (PLIN3) was subsequently confirmed using shRNA. Our investigation revealed that the relative abundance of P. intermedia in tumor tissues significantly surpassed that of corresponding healthy tissues. The abundance of P. intermedia exhibited correlations with tumor differentiation (p = 0.006), perineural invasion (p = 0.004), omentum majus invasion (p = 0.040), and the survival duration of GC patients (p = 0.042). The supernatant derived from tumor-associated P. intermedia bolstered the proliferation, clone formation, migration, and invasion of GC cells. After indirect co-cultivation with tumor-derived P. intermedia, dysregulation of 34 proteins, including PLIN3, was discerned in GC cells. Knockdown of PLIN3 mitigated the malignancy instigated by P. intermedia in GC cells. Our findings posit that P. intermedia from the tumor microenvironment plays a substantial role in the malignant progression of GC via the modulation of PLIN3 expression. Moreover, the relative abundance of P. intermedia might serve as a potential biomarker for the diagnosis and prognosis of GC.


Assuntos
Neoplasias Gástricas , Humanos , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Perilipina-3 , Prevotella intermedia , Prognóstico , Neoplasias Gástricas/patologia , Microambiente Tumoral
13.
BMC Plant Biol ; 24(1): 697, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044138

RESUMO

BACKGROUND: In recent years, global climate change in tandem with increased human activity has resulted in habitat degradation or the migration of rare medicinal plants, potentially impacting the quality of medicinal herbs. Astragalus membranaceus var. mongholicus is a valuable bulk medicinal material in Northwest China. As the demand for this medicinal herb continues to increase in both domestic and international markets, ensuring the sustainable development of high-quality Astragali Radix is important. In this study, the maximum entropy (Maxent) model was applied, thereby incorporating 136 distribution records, along with 39 environmental factors of A. membranaceus var. mongholicus, to assess the quality zonation and potential distribution of this species in China under climate change. RESULTS: The results showed that the elevation, annual mean temperature, precipitation of wettest month, solar radiation in June, and mean temperature of warmest quarter were the critical environmental factors influencing the accumulation of astragaloside IV and Astragalus polysaccharide in A. membranaceus var. mongholicus. Among the twelve main environmental variables, annual mean temperature, elevation, precipitation of the wettest month, and solar radiation in November were the four most important factors influencing the distribution of A. membranaceus var. mongholicus. In addition, ecological niche modelling revealed that highly suitable habitats were mainly located in central and western Gansu, eastern Qinghai, northern Shaanxi, southern Ningxia, central Inner Mongolia, central Shanxi, and northern Hebei. However, the future projections under climate change suggested a contraction of these suitable areas, shifting towards northeastern high-latitude and high-elevation mountains. CONCLUSIONS: The findings provide essential insights for developing adaptive strategies for A. membranaceus var. mongholicus cultivation in response to climate change and can inform future research on this species. By considering the identified environmental factors and the potential impacts of the predicted climate changes, we can visualize the regional distribution of high-quality Radix Astragali and develop conservation strategies to protect and restore its suitable habitats.


Assuntos
Astragalus propinquus , Mudança Climática , Triterpenos , China , Triterpenos/análise , Cromatografia Líquida de Alta Pressão , Saponinas/análise , Plantas Medicinais/química , Meio Ambiente , Temperatura , Polissacarídeos/análise
14.
J Transl Med ; 22(1): 796, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198913

RESUMO

BACKGROUND: Liver surgery during the perioperative period often leads to a significant complication known as hepatic ischemia-reperfusion (I/R) injury. Hepatic I/R injury is linked to the innate immune response. The cGAS-STING pathway triggers the activation of innate immune through the detection of DNA within cells. Nevertheless, the precise mechanism and significance of the cGAS-STING pathway in hepatic I/R injury are yet to be investigated. METHODS: Mouse model of hepatic I/R injury was used in the C57BL/6 WT mice and the STING knockout (STING-KO) mice. In addition, purified primary hepatocytes were used to construct oxygen-glucose deprivation reperfusion (OGD-Rep) treatment models. RESULTS: Our research revealed a notable increase in mRNA and protein levels of cGAS and STING in liver during I/R injury. Interestingly, the lack of STING exhibited a safeguarding impact on hepatic I/R injury by suppressing the elevation of liver enzymes, liver cell death, and inflammation. Furthermore, pharmacological cGAS and STING inhibition recapitulated these phenomena. Macrophages play a crucial role in the activation of the cGAS-STING pathway during hepatic I/R injury. The cGAS-STING pathway experiences a significant decrease in activity and hepatic I/R injury is greatly diminished following the elimination of macrophages. Significantly, we demonstrate that the activation of the cGAS-STING pathway is primarily caused by the liberation of mitochondrial DNA (mtDNA) rather than nuclear DNA (nDNA). Moreover, the safeguarding of the liver against I/R injury is also attributed to the hindrance of mtDNA release through the utilization of inhibitors targeting mPTP and VDAC oligomerization. CONCLUSIONS: The results of our study suggest that the release of mtDNA plays a significant role in causing damage to liver by activating the cGAS-STING pathway during I/R injury. Furthermore, inhibiting the release of mtDNA can provide effective protection against hepatic I/R injury.


Assuntos
DNA Mitocondrial , Fígado , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotidiltransferases , Traumatismo por Reperfusão , Transdução de Sinais , Animais , DNA Mitocondrial/metabolismo , DNA Mitocondrial/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Nucleotidiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Fígado/metabolismo , Fígado/patologia , Fígado/irrigação sanguínea , Masculino , Hepatócitos/metabolismo , Camundongos , Macrófagos/metabolismo
15.
Opt Express ; 32(2): 2321-2332, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297765

RESUMO

Deep learning-based computer-generated holography (DeepCGH) has the ability to generate three-dimensional multiphoton stimulation nearly 1,000 times faster than conventional CGH approaches such as the Gerchberg-Saxton (GS) iterative algorithm. However, existing DeepCGH methods cannot achieve axial confinement at the several-micron scale. Moreover, they suffer from an extended inference time as the number of stimulation locations at different depths (i.e., the number of input layers in the neural network) increases. Accordingly, this study proposes an unsupervised U-Net DeepCGH model enhanced with temporal focusing (TF), which currently achieves an axial resolution of around 5 µm. The proposed model employs a digital propagation matrix (DPM) in the data preprocessing stage, which enables stimulation at arbitrary depth locations and reduces the computation time by more than 35%. Through physical constraint learning using an improved loss function related to the TF excitation efficiency, the axial resolution and excitation intensity of the proposed TF-DeepCGH with DPM rival that of the optimal GS with TF method but with a greatly increased computational efficiency.

16.
Liver Int ; 44(4): 920-930, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38291865

RESUMO

BACKGROUND & AIMS: Our retrospective study has suggested encouraging outcomes of lenvatinib combined with PD-1 inhibitor and transarterial chemoembolization (TACE) on advanced hepatocellular carcinoma (HCC). This phase II trial was conducted to prospectively investigate the efficacy and safety of lenvatinib, sintilimab (a PD-1 inhibitor) plus TACE (Len-Sin-TACE) in patients with advanced stage HCC. METHODS: This was a single-arm phase II trial. Patients with BCLC stage C HCC were recruited. They received lenvatinib (bodyweight ≥60 kg, 12 mg; bodyweight <60 kg, 8 mg) orally once daily, sintilimab (200 mg) intravenously once every 3 weeks, and on demand TACE. The primary endpoint was progression-free survival (PFS) per mRECIST. RESULTS: Thirty patients were enrolled. The primary endpoint was met with a median PFS of 8.0 (95% confidence interval [CI]: 6.1-9.8) months per mRECIST, which was the same as that per RECIST 1.1. The objective response rate was 60.0% per mRECIST and 30.0% per RECIST 1.1. The disease control rate was 86.7% per mRECIST/RECIST 1.1. The median duration of response was 7.4 (95% CI: 6.6-8.2) months per mRECIST (n = 18) and 4.3 (95% CI: 4.0-4.6) months per RECIST 1.1 (n = 9). The median overall survival was 18.4 (95% CI: 14.5-22.3) months. Treatment-related adverse events (TRAEs) occurred in 28 patients (93.3%) and grade 3 TRAEs were observed in 12 patients (40.0%). There were no grade 4/5 TRAEs. CONCLUSIONS: Len-Sin-TACE showed promising antitumour activities with a manageable safety profile in patients with advanced stage HCC. The preliminary results need to be further evaluated with phase III randomized trials.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Compostos de Fenilureia , Quinolinas , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Hepatocelular/terapia , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas/terapia , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/uso terapêutico , Quinolinas/efeitos adversos , Quinolinas/uso terapêutico , Estudos Retrospectivos
17.
Vet Res ; 55(1): 37, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532498

RESUMO

In the last decade, prophages that possess the ability of lysogenic transformation have become increasingly significant. Their transfer and subsequent activity in the host have a significant impact on the evolution of bacteria. Here, we investigate the role of prophage phi456 with high spontaneous induction in the bacterial genome of Avian pathogenic Escherichia coli (APEC) DE456. The phage particles, phi456, that were released from DE456 were isolated, purified, and sequenced. Additionally, phage particles were no longer observed either during normal growth or induced by nalidixic acid in DE456Δphi456. This indicated that the released phage particles from DE456 were only phi456. We demonstrated that phi456 contributed to biofilm formation through spontaneous induction of the accompanying increase in the eDNA content. The survival ability of DE456Δphi456 was decreased in avian macrophage HD11 under oxidative stress and acidic conditions. This is likely due to a decrease in the transcription levels of three crucial genes-rpoS, katE, and oxyR-which are needed to help the bacteria adapt to and survive in adverse environments. It has been observed through animal experiments that the presence of phi456 in the DE456 genome enhances colonization ability in vivo. Additionally, the number of type I fimbriae in DE456Δphi456 was observed to be reduced under transmission electron microscopy when compared to the wild-type strain. The qRT-PCR results indicated that the expression levels of the subunit of I fimbriae (fimA) and its apical adhesin (fimH) were significantly lower in DE456Δphi456. Therefore, it can be concluded that phi456 plays a crucial role in helping bacterial hosts survive in unfavorable conditions and enhancing the colonization ability in DE456.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Animais , Escherichia coli/genética , Prófagos/genética , Galinhas/microbiologia , Adesinas Bacterianas/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária
18.
J Org Chem ; 89(1): 644-655, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38088130

RESUMO

A photoredox-catalyzed intermolecular tandem sulfonamination/cyclization of enaminones was realized by using N-aminopyridinium salts as the sulfonaminated reagents without transition-metal catalysts or bases. The reaction exhibits a broad scope and good functional group tolerance, good yields, and regioselectivity. Preliminary mechanistic studies support the radical property of the reaction and the involvement of N-centered radical intermediates.

19.
Psychophysiology ; 61(4): e14479, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37920144

RESUMO

The locus coeruleus-norepinephrine (LC-NE) system, which regulates arousal levels, is important for cognitive control, including emotional conflict resolution. Additionally, the LC-NE system is implicated in P300 generation. If the P300 is mediated by the LC-NE system, and considering the established correlations between LC activity and pupil dilation, P300 amplitude should correlate with task-evoked (phasic) pupil dilation on a trial-by-trial basis. However, prior studies, predominantly utilizing oddball-type paradigms, have not demonstrated correlations between concurrently recorded task-evoked pupil dilation and P300 responses. Using a recently developed emotional face-word Stroop task that links pupil dilation to the LC-NE system, here, we examined both intra- and inter-individual correlations between task-evoked pupil dilation and P300 amplitude. We found that lower accuracy, slower reaction times, and larger task-evoked pupil dilation were obtained in the incongruent compared to the congruent condition. Furthermore, we observed intra-individual correlations between task-evoked pupil dilation and P300 amplitude, with larger pupil dilation correlating with a greater P300 amplitude. In contrast, pupil dilation did not exhibit consistent correlations with N450 and N170 amplitudes. Baseline (tonic) pupil size also showed correlations with P300 and N170 amplitudes, with smaller pupil size corresponding to larger amplitude. Moreover, inter-individual differences in task-evoked pupil dilation between the congruent and incongruent conditions correlated with differences in reaction time and P300 amplitude, though these effects only approached significance. To summarize, our study provides evidence for a connection between task-evoked pupil dilation and P300 amplitude at the single-trial level, suggesting the involvement of the LC-NE system in P300 generation.


Assuntos
Nível de Alerta , Pupila , Humanos , Teste de Stroop , Pupila/fisiologia , Tempo de Reação/fisiologia , Nível de Alerta/fisiologia , Locus Cerúleo/fisiologia , Norepinefrina/fisiologia
20.
Nanotechnology ; 35(38)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958589

RESUMO

Green energy technology is generally becoming one of hot issues that need to be solved due to the adverse effects on the environment of fossil fuels. One of the strategies being studied and developed by theorists and experimentalists is the use of photoelectrochemical (PEC) cells, which are emerging as a candidate to produce hydrogen from water splitting. However, creating photoelectrodes that meet the requirements for PEC water splitting has emerged as the primary obstacle in bringing this technology to commercial fruition. Here, we construct a heterostructure, which consists of MoS2/TiO2/Au nanoparticles (NPs) to overcome the drawbacks of the photoanode. Owing to the dependence on charge transfer, the bandgap of MoS2/TiO2and the utilization the Au NPs as a stimulant for charges separation of TiO2by localized surface plasmon resonances effect as well as the increase of hot electron injection to cathode, leading to photocatalytic activities are improved. The results have recorded a significant increase in the photocurrent density from 2.3µAcm-2of TiO2to approximately 16.3µAcm-2of MoS2/TiO2/Au NPs. This work unveils a promising route to enhance the visible light adsorption and charge transfer in photo-electrode of the PEC cells by combining two-dimensional materials with metal NPs.

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