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Limited infiltration and activity of natural killer (NK) and T cells within the tumor microenvironment (TME) correlate with poor immunotherapy responses. Here, we examined the role of the endonuclease Regnase-1 on NK cell anti-tumor activity. NK cell-specific deletion of Regnase-1 (Reg1ΔNK) augmented cytolytic activity and interferon-gamma (IFN-γ) production in vitro and increased intra-tumoral accumulation of Reg1ΔNK-NK cells in vivo, reducing tumor growth dependent on IFN-γ. Transcriptional changes in Reg1ΔNK-NK cells included elevated IFN-γ expression, cytolytic effectors, and the chemokine receptor CXCR6. IFN-γ induced expression of the CXCR6 ligand CXCL16 on myeloid cells, promoting further recruitment of Reg1ΔNK-NK cells. Mechanistically, Regnase-1 deletion increased its targets, the transcriptional regulators OCT2 and IκBζ, following interleukin (IL)-12 and IL-18 stimulation, and the resulting OCT2-IκBζ-NF-κB complex induced Ifng transcription. Silencing Regnase-1 in human NK cells increased the expression of IFNG and POU2F2. Our findings highlight NK cell dysfunction in the TME and propose that targeting Regnase-1 could augment active NK cell persistence for cancer immunotherapy.
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Interferon gama , Células Matadoras Naturais , Microambiente Tumoral , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Animais , Interferon gama/metabolismo , Humanos , Camundongos , Microambiente Tumoral/imunologia , Camundongos Endogâmicos C57BL , Ribonucleases/metabolismo , Ribonucleases/genética , Camundongos Knockout , Transcrição Gênica , Linhagem Celular Tumoral , NF-kappa B/metabolismoRESUMO
Regnase-1 is an RNase that plays a critical role in negatively regulating immune responses by destabilizing inflammatory mRNAs. Dysfunction of Regnase-1 can be a major cause of various inflammatory diseases with tissue injury and immune cell infiltration into organs. This study focuses on the role of RNase activity of Regnase-1 in developing inflammatory diseases. We have constructed mice with a single point mutation at the catalytic center of Regnase-1 RNase domain, which lacks endonuclease activity. D141N mutant mice demonstrated systemic inflammation, immune cell infiltration into various organs and progressive development of lung granuloma. CD4+ T cells, mainly affected by this mutation, upregulated mTORC1 pathway and facilitated the autoimmune trait in D141N mutation. Moreover, serine/threonine kinase Pim2 contributed to lung inflammation in this mutation. Inhibition of Pim2 kinase activity ameliorated granulomatous inflammation, immune cell infiltration and proliferation in the lungs. Additionally, Pim2 inhibition reduced the expression of adhesion molecules on CD4+ T cells, suggesting a role for Pim2 in facilitating leukocyte adhesion and migration to inflamed tissues. Our findings provide new insights into the role of Regnase-1 RNase activity in controlling immune function and underscore the therapeutic relevance of targeting Pim2 to modulate abnormal immune responses.
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RFWD3 is a recently identified Fanconi anemia protein FANCW whose E3 ligase activity toward RPA is essential in homologous recombination (HR) repair. However, how RPA ubiquitination promotes HR remained unknown. Here, we identified RAD51, the central HR protein, as another target of RFWD3. We show that RFWD3 polyubiquitinates both RPA and RAD51 in vitro and in vivo. Phosphorylation by ATR and ATM kinases is required for this activity in vivo. RFWD3 inhibits persistent mitomycin C (MMC)-induced RAD51 and RPA foci by promoting VCP/p97-mediated protein dynamics and subsequent degradation. Furthermore, MMC-induced chromatin loading of MCM8 and RAD54 is defective in cells with inactivated RFWD3 or expressing a ubiquitination-deficient mutant RAD51. Collectively, our data reveal a mechanism that facilitates timely removal of RPA and RAD51 from DNA damage sites, which is crucial for progression to the late-phase HR and suppression of the FA phenotype.
Assuntos
Cromatina/enzimologia , Dano ao DNA , DNA/metabolismo , Anemia de Fanconi/enzimologia , Rad51 Recombinase/metabolismo , Reparo de DNA por Recombinação , Proteína de Replicação A/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sítios de Ligação , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/genética , Cromatina/efeitos da radiação , DNA/genética , Anemia de Fanconi/genética , Humanos , Proteínas de Manutenção de Minicromossomo/metabolismo , Mitomicina/farmacologia , Mutação , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteólise , Interferência de RNA , Rad51 Recombinase/genética , Reparo de DNA por Recombinação/efeitos dos fármacos , Reparo de DNA por Recombinação/efeitos da radiação , Proteína de Replicação A/genética , Transfecção , Ubiquitina-Proteína Ligases/genética , Proteína com ValosinaRESUMO
Histone replacement by transition proteins (TPs) and protamines (Prms) constitutes an essential step for the successful production of functional male gametes, yet nothing is known on the underlying functional interplay between histones, TPs, and Prms. Here, by studying spermatogenesis in the absence of a spermatid-specific histone variant, H2A.L.2, we discover a fundamental mechanism involved in the transformation of nucleosomes into nucleoprotamines. H2A.L.2 is synthesized at the same time as TPs and enables their loading onto the nucleosomes. TPs do not displace histones but rather drive the recruitment and processing of Prms, which are themselves responsible for histone eviction. Altogether, the incorporation of H2A.L.2 initiates and orchestrates a series of successive transitional states that ultimately shift to the fully compacted genome of the mature spermatozoa. Hence, the current view of histone-to-nucleoprotamine transition should be revisited and include an additional step with H2A.L.2 assembly prior to the action of TPs and Prms.
Assuntos
Montagem e Desmontagem da Cromatina , Cromatina/metabolismo , Histonas/metabolismo , Nucleossomos/metabolismo , Protaminas/metabolismo , Espermatogênese , Espermatozoides/metabolismo , Animais , Células COS , Chlorocebus aethiops , Cromatina/genética , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Biologia Computacional , Bases de Dados Genéticas , Fertilidade , Regulação da Expressão Gênica no Desenvolvimento , Predisposição Genética para Doença , Genoma , Histonas/deficiência , Histonas/genética , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Masculino , Camundongos da Linhagem 129 , Camundongos Knockout , Nucleossomos/genética , Fenótipo , Espermatogênese/genética , Espermatozoides/patologia , TransfecçãoRESUMO
Androgen-deprivation therapy is a standard treatment for advanced prostate cancer. However, most patients eventually acquire resistance and progress to castration-resistant prostate cancer (CRPC). In this study, we established new CRPC cell lines, AILNCaP14 and AILNCaP15, from LNCaP cells under androgen-deprived conditions. Unlike most pre-existing CRPC cell lines, both cell lines expressed higher levels of androgen receptor (AR) and prostate-specific antigen (PSA) than parental LNCaP cells. Moreover, these cells exhibited primary resistance to enzalutamide. Since AR signaling plays a significant role in the development of CRPC, PSA promoter sequences fused with GFP were introduced into AILNCaP14 cells to conduct GFP fluorescence-based chemical screening. We identified flavopiridol, a broad-spectrum CDK inhibitor, as a candidate drug that could repress AR transactivation of CRPC cells, presumably through the inhibition of phosphorylation of AR on the serine 81 residue (pARSer81 ). Importantly, this broad-spectrum CDK inhibitor inhibited the proliferation of AILNCaP14 cells both in vitro and in vivo. Moreover, a newly developed liver metastatic model using AILNCaP15 cells revealed that the compound attenuated tumor growth of CRPC harboring highly metastatic properties. Finally, we developed a patient-derived xenograft (PDX) model of CRPC and DCaP CR from a patient presenting therapeutic resistance to enzalutamide, abiraterone, and docetaxel. Flavopiridol successfully suppressed the tumor growth of CRPC in this PDX model. Since ARSer81 was found to be phosphorylated in clinical CRPC samples, our data suggested that broad-spectrum CDK inhibitors might be a potent candidate drug for the treatment of CRPC, including those exhibiting primary resistance to enzalutamide.
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Benzamidas , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/metabolismo , Antígeno Prostático Específico , Antagonistas de Androgênios/uso terapêutico , Androgênios , Resistencia a Medicamentos Antineoplásicos , Receptores Androgênicos/metabolismo , Nitrilas/uso terapêutico , Linhagem Celular TumoralRESUMO
Metastatic spinal tumors are increasingly prevalent due to advancements in cancer treatment, leading to prolonged survival rates. This rising prevalence highlights the need for developing more effective therapeutic approaches to address this malignancy. Boron neutron capture therapy (BNCT) offers a promising solution by delivering targeted doses to tumors while minimizing damage to normal tissue. In this study, we evaluated the efficacy and safety of BNCT as a potential therapeutic option for spine metastases in mouse models induced by A549 human lung adenocarcinoma cells. The animal models were randomly allocated into three groups: untreated (n = 10), neutron irradiation only (n = 9), and BNCT (n = 10). Each mouse was administered 4-borono-L-phenylalanine (250 mg/kg) intravenously, followed by measurement of boron concentrations 2.5 h later. Overall survival, neurological function of the hindlimb, and any adverse events were assessed post irradiation. The tumor-to-normal spinal cord and blood boron concentration ratios were 3.6 and 2.9, respectively, with no significant difference observed between the normal and compressed spinal cord tissues. The BNCT group exhibited significantly prolonged survival rates compared with the other groups (vs. untreated, p = 0.0015; vs. neutron-only, p = 0.0104, log-rank test). Furthermore, the BNCT group demonstrated preserved neurological function relative to the other groups (vs. untreated, p = 0.0004; vs. neutron-only, p = 0.0051, multivariate analysis of variance). No adverse events were observed post irradiation. These findings indicate that BNCT holds promise as a novel treatment modality for metastatic spinal tumors.
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Terapia por Captura de Nêutron de Boro , Modelos Animais de Doenças , Neoplasias da Coluna Vertebral , Terapia por Captura de Nêutron de Boro/métodos , Animais , Camundongos , Humanos , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/secundário , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Fenilalanina/análogos & derivados , Fenilalanina/uso terapêutico , Células A549 , Medula Espinal/efeitos da radiação , Medula Espinal/patologia , Linhagem Celular Tumoral , Boro/uso terapêutico , FemininoRESUMO
The IL-6 amplifier was originally discovered as a mechanism for the enhanced activation of NF-κB in non-immune cells. In the IL-6 amplifier, IL-6-STAT3 and NF-κB stimulation is followed by an excessive production of IL-6, chemokines, and growth factors to develop chronic inflammation preceding the development of inflammatory diseases. Previously, using a shRNA-mediated genome-wide screening, we found that DEAD-Box Helicase 6 (DDX6) is a candidate positive regulator of the amplifier. Here, we investigate whether DDX6 is involved in the pathogenesis of inflammatory diseases via the IL-6 amplifier. We found that DDX6-silencing in non-immune cells suppressed the NF-κB pathway and inhibited activation of the IL-6 amplifier, while the forced expression of DDX6 enhanced NF-κB promoter activity independent of the RNA helicase activity of DDX6. The imiquimod-mediated dermatitis model was suppressed by the siRNA-mediated gene downregulation of DDX6. Furthermore, silencing DDX6 significantly reduced the TNF-α-induced phosphorylation of p65/RelA and IκBα, nuclear localization of p65, and the protein levels of IκBα. Mechanistically, DDX6 is strongly associated with p65 and IκBα, but not TRADD, RIP, or TRAF2, suggesting a novel function of DDX6 as an adaptor protein in the NF-κB pathway. Thus, our findings demonstrate a possible role of DDX6 beyond RNA metabolism and suggest DDX6 is a therapeutic target for inflammatory diseases.
Assuntos
RNA Helicases DEAD-box , NF-kappa B , Regulação da Expressão Gênica , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , RNA Helicases DEAD-box/metabolismoRESUMO
The RNA-binding protein (RBP) Regnase-1 is an endonuclease that regulates immune responses by modulating target mRNA stability. Regnase-1 degrades a group of inflammation-associated mRNAs, which contributes to a balanced immune response and helps prevent autoimmune diseases. Regnase-1 also cleaves its own mRNA by binding stem-loop (SL) RNA structures in its 3'UTR. To understand how this autoregulation is important for immune responses, we generated mice with a 2-bp genome deletion in the target SL of the Regnase-1 3'-untranslated region (3'UTR). Deletion of these nucleotides inhibited SL formation and limited Regnase-1-mediated mRNA degradation. Mutant mice had normal hematopoietic cell differentiation. Biochemically, mutation of the 3'UTR SL increased Regnase-1 mRNA stability and enhanced both Regnase-1 mRNA and protein levels in mouse embryonic fibroblasts (MEFs). The expression of Il6, a Regnase-1 target gene, was constitutively suppressed at steady-state in mutant MEFs. Additionally, Regnase-1 protein expression in mutant MEFs was significantly elevated compared to that in wild-type MEFs at steady state and upon proinflammatory cytokine stimulation. These data suggest a negative feedback mechanism for Regnase-1 expression and represent a unique mouse model to probe Regnase-1 overexpression in vivo.
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Ribonucleases , Autocontrole , Animais , Camundongos , Ribonucleases/genética , Regiões 3' não Traduzidas/genética , Fibroblastos/metabolismo , Inflamação/genéticaRESUMO
We propose an approach to evaluate solid-state media for laser cooling by anti-Stokes fluorescence employing a Monte Carlo-based simulation of fluorescence ray tracing. This approach prompted a revisit of the experimental method, laser-induced thermal modulation spectroscopy (LITMoS), showing that the external quantum efficiency and the background absorption coefficient can be retrieved solely from the two wavelengths where neither cooling nor heating is observed. Our simulation can accurately compute two experimentally inaccessible quantities essential to evaluate laser-cooling media: the mean fluorescence wavelength and the fluorescence escape efficiency. These computed quantities in combination with LITMoS results allow us to retrieve the internal quantum efficiency which is a performance indicator independent of various factors such as the sample size and doping level. Using the proposed approach, we thoroughly investigate the impact of doping level, sample geometry, and refractive index on the fluorescence escape efficiency and reveal its temperature dependency for the example of Yb:YLF. Through comprehensive numerical analysis, we demonstrate that the reduction of sample symmetry is crucial in achieving lower cooling temperatures.
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The dorsolateral prefrontal cortex has been shown to be associated with prosocial behavior. However, the direction of this relationship remains controversial. To resolve inconsistencies in the existing literature, we introduced the concept of default prosociality preference and hypothesized that this preference moderates the relationship between gray matter volume in the dorsolateral prefrontal cortex and prosocial behavior. This study analyzed the data of 168 participants obtained from voxel-based morphometry, 4 types of economic games, and 3 different measures of social value orientation that represent default prosociality preference. Here we show that, in individuals who were consistently classified as proself on the 3 social value orientation measures, gray matter volume in the right dorsolateral prefrontal cortex was positively associated with prosocial behavior. However, in individuals who were consistently classified as prosocial, the direction of this association was vice versa. These results indicate that the right dorsolateral prefrontal cortex regulates default prosociality preference.
Assuntos
Córtex Pré-Frontal Dorsolateral , Córtex Pré-Frontal , Humanos , Córtex Pré-Frontal/fisiologia , Imageamento por Ressonância Magnética/métodos , Substância Cinzenta , Córtex CerebralRESUMO
RNA vaccines based on Lipid nanoparticles (LNP) were put into practical use within only one year after the global outbreak of the coronavirus disease 2019 (COVID-19). This success of RNA vaccine highlights the utility of an mRNA delivery system as a vaccination strategy. Potent immunostimulatory activity of LNPs (i.e., inflammation occurring at the injection site and the production of inflammatory cytokines) have recently been reported. However, we have only limited knowledge concerning which cells are responsible for responding to the LNPs. We report herein on in vitro chemokine production from non-immune cells in response to exposure to LNPs. In this study, SM-102, an ionizable lipid that is used in the approved RNA vaccine for the clinical usage of COVID-19 mRNA vaccine, was used. Immortalized mouse lymphatic endothelial cells (mLECs) or professional antigen presenting cells (APCs) such as RAW 264.7 monocyte/macrophage cells were incubated with LNPs that contained no mRNA. As a result, chemokines involved in the recruitment of monocytes/neutrophils were produced only by the mLECs following the LNP treatment. These findings indicate that LEC appear to serve as the cell that sends out initial signals to response LNPs.
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COVID-19 , Lipossomos , Nanopartículas , Animais , Humanos , Camundongos , Vacinas de mRNA , Vacinas contra COVID-19 , Células Endoteliais , Quimiocinas , RNA Mensageiro , RNA Interferente PequenoRESUMO
Chronic obstructive pulmonary disease (COPD/emphysema) is a life-threatening disorder and there are few effective therapies. Cigarette smoke-induced oxidative stress, airway inflammation, and apoptosis of lung cells have been reported to be involved in the pathogenesis of COPD/emphysema and lead to alveolar septal destruction. Here we show that the expression level of FCH and double SH3 domains 1 (FCHSD1) was drastically increased in mice in response to elastase instillation, an experimental model of COPD. FCHSD1 is a member of the F-BAR family with two SH3 domains. We found that Fchsd1 knockout (Fchsd1-/-) mice were protected against airspace enlargement induced by elastase. Elastase-instilled lungs of Fchsd1-/- mice showed reduced inflammation and apoptosis compared with WT mice. We also found that elastase-induced reduction of Sirtuin 1 (SIRT1) levels, a histone deacetylase reported to protect against emphysema, was attenuated in the lungs of Fchsd1-/- mice. Furthermore, FCHSD1 deficiency enhanced nuclear translocation of nuclear factor-like 2 (NRF2), a redox-sensitive transcription factor, following H2O2 stimulation. Conversely, Fchsd1 overexpression inhibited NRF2 nuclear translocation and increased the reduction of SIRT1 levels. Notably, FCHSD1 interacted with NRF2 and SNX9. Our results show that FCHSD1 forms a multicomplex with NRF2 and SNX9 in the cytosol that prevents NRF2 from translocating to the nucleus. We propose that FCHSD1 promotes initiation of emphysema development by inhibiting nuclear translocation of NRF2, which leads to down-regulation of SIRT1.
Assuntos
Proteínas de Membrana/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Apoptose , Morte Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Peróxido de Hidrogênio/toxicidade , Carioferinas , Pulmão/patologia , Masculino , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Elastase Pancreática , Pneumonia/complicações , Pneumonia/patologia , Ligação Proteica/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/complicações , Enfisema Pulmonar/prevenção & controle , Sirtuína 1/metabolismo , Nexinas de Classificação/metabolismoRESUMO
Theiler's murine encephalomyelitis virus (TMEV) infection has been used as a mouse model for two virus-induced organ-specific immune-mediated diseases. TMEV-induced demyelinating disease (TMEV-IDD) in the central nervous system (CNS) is a chronic inflammatory disease with viral persistence and an animal model of multiple sclerosis (MS) in humans. TMEV infection can also cause acute myocarditis with viral replication and immune cell infiltration in the heart, leading to cardiac fibrosis. Since platelets have been reported to modulate immune responses, we aimed to determine the role of platelets in TMEV infection. In transcriptome analyses of platelets, distinct sets of immune-related genes, including major histocompatibility complex (MHC) class I, were up- or downregulated in TMEV-infected mice at different time points. We depleted platelets from TMEV-infected mice by injecting them with platelet-specific antibodies. The platelet-depleted mice had significantly fewer viral antigen-positive cells in the CNS. Platelet depletion reduced the severities of TMEV-IDD and myocarditis, although the pathology scores did not reach statistical significance. Immunologically, the platelet-depleted mice had an increase in interferon (IFN)-γ production with a higher anti-TMEV IgG2a/IgG1 ratio. Thus, platelets may play roles in TMEV infection, such as gene expression, viral clearance, and anti-viral antibody isotype responses.
Assuntos
Esclerose Múltipla , Miocardite , Humanos , Camundongos , Animais , Miocardite/etiologia , Miocardite/metabolismo , Sistema Nervoso Central/metabolismo , Esclerose Múltipla/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Doença CrônicaRESUMO
The spatial-frequency (SF) tuning of neurons in the early visual cortex is adjusted for stimulus contrast. As the contrast increases, SF tuning is modulated so that the transmission of fine features is facilitated. A variety of mechanisms are involved in shaping SF tunings, but those responsible for the contrast-dependent modulations are unclear. To address this, we measured the time course of SF tunings of area 17 neurons in male cats under different contrasts with a reverse correlation. After response onset, the optimal SF continuously shifted to a higher SF over time, with a larger shift for higher contrast. At high contrast, whereas neurons with a large shift of optimal SF exhibited a large bandwidth decrease, those with a negligible shift increased the bandwidth over time. Between these two extremes, the degree of SF shift and bandwidth change continuously varied. At low contrast, bandwidth generally decreased over time. These dynamic effects enhanced the processing of high-frequency range under a high-contrast condition and allowed time-average SF tuning curves to show contrast-dependent modulation, like that of steady-state SF tuning curves reported previously. Combinations of two mechanisms, one that decreases bandwidth and shifts optimal SF, and another that increases bandwidth without shifting optimal SF, would explain the full range of SF tuning dynamics. Our results indicate that one of the essential roles of tuning dynamics of area 17 neurons, which have been observed for various visual features, is to adjust tunings depending on contrast.SIGNIFICANCE STATEMENT The spatial scales of features transmitted by cortical neurons are adjusted depending on stimulus contrast. However, the underlying mechanism is not fully understood. We measured the time course of spatial frequency tunings of cat area 17 neurons under different contrast conditions and observed a variety of dynamic effects that contributed to spatial-scale adjustment, allowing neurons to adjust their spatial frequency tuning range depending on contrast. Our results suggest that one of the essential roles of tuning dynamics of area 17 neurons, which have been observed for various visual features, is to adjust tunings depending on contrast.
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Córtex Visual , Animais , Masculino , Neurônios/fisiologia , Estimulação Luminosa/métodos , Córtex Visual/fisiologiaRESUMO
Sphingolipidoses are inherited metabolic disorders associated with glycosphingolipids accumulation, neurodegeneration, and neuroinflammation leading to severe neurological symptoms. Lysoglycosphingolipids (lysoGSLs), also known to accumulate in the tissues of sphingolipidosis patients, exhibit cytotoxicity. LysoGSLs are the possible pathogenic cause, but the mechanisms are still unknown in detail. Here, we first show that lysoGSLs are potential inhibitors of phosphoinositide 3-kinase (PI3K) to reduce cell survival signaling. We found that phosphorylated Akt was commonly reduced in fibroblasts from patients with sphingolipidoses, including GM1/GM2 gangliosidoses and Gaucher's disease, suggesting the contribution of lysoGSLs to the pathogenesis. LysoGSLs caused cell death and decreased the level of phosphorylated Akt as in the patient fibroblasts. Extracellularly administered lysoGM1 permeated the cell membrane to diffusely distribute in the cytoplasm. LysoGM1 and lysoGM2 also inhibited the production of phosphatidylinositol-(3,4,5)-triphosphate and the translocation of Akt from the cytoplasm to the plasma membrane. We also predicted that lysoGSLs could directly bind to the catalytic domain of PI3K by in silico docking study, suggesting that lysoGSLs could inhibit PI3K by directly interacting with PI3K in the cytoplasm. Furthermore, we revealed that the increment of lysoGSLs amounts in the brain of sphingolipidosis model mice correlated with the neurodegenerative progression. Our findings suggest that the down-regulation of PI3K/Akt signaling by direct interaction of lysoGSLs with PI3K in the brains is a neurodegenerative mechanism in sphingolipidoses. Moreover, we could propose the intracellular PI3K activation or inhibition of lysoGSLs biosynthesis as novel therapeutic approaches for sphingolipidoses because lysoGSLs should be cell death mediators by directly inhibiting PI3K, especially in neurons.
Assuntos
Fosfatidilinositol 3-Quinases , Esfingolipidoses , Humanos , Camundongos , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Esfingolipidoses/metabolismo , Morte CelularRESUMO
Acetaminophen (APAP) hepatotoxicity is one of the biggest drawbacks of this relatively safe and widely used drug. In addition to its hepatotoxicity, APAP also cause comparable levels of toxicity on human hepatoma cells. Here we show activation of the intrinsic caspase-9/3 pathway of apoptosis followed by gasdermin E (GSDME) cleavage and subsequent ballooning in APAP (10 mM, 72 h)-treated Huh-7 human hepatocarcinoma cells. N-acetylcysteine (NAC), an antioxidant currently used as an antidote for APAP overdose, does not alleviate APAP toxicity in Huh-7 cells; NAC overdose (10 mM) rather aggravates APAP toxicity. NAC overdose not only aggravates cell death, but also decreases the cellular GSH/GSSG ratio, an indicator of redox homeostasis of glutathione. These results show for the first time that APAP-induced apoptosis in hepatoma cells is followed by secondary necrosis via the caspase-3/GSDME pathway. NAC overdose (10 mM) not only worsens the glutathione redox status, but also accelerates this pathway.
Assuntos
Carcinoma Hepatocelular , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Hepáticas , Humanos , Acetilcisteína/metabolismo , Acetaminofen/toxicidade , Carcinoma Hepatocelular/patologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Glutationa/metabolismo , Neoplasias Hepáticas/patologia , Apoptose , Oxirredução , Homeostase , Fígado/metabolismoRESUMO
The reactivation of anticancer immunity is a fundamental principle in cancer immunotherapy as evidenced by the use of immune checkpoint inhibitors (ICIs). While treatment with the ICIs is shown to have remarkable and durable therapeutic effects in the responders, the low objective response rate (<40%) continues to be a major problem. Since myeloid-derived suppressor cells (MDSCs), heterogenous cells with strong immunosuppressive activity that originate in the hematopoietic system, suppress the anticancer immunity via parallel immune checkpoint-dependent and independent pathways, these cells are potential targets for improving the efficacy of cancer immunotherapy. In this study, it is demonstrated that MDSCs can be depleted by delivering synthetic glucocorticoid dexamethasone to phagocytic cells in the spleen using a lipid nanoparticle. Since the interaction of nanoparticles with T cells is intrinsically poor, this strategy also enables the "detargeting" from T cells, thus avoiding the nonspecific suppression of cytotoxic immune responses against cancer cells. In addition to the direct anticancer effect of the nanoparticulated dexamethasone, their synergistic anticancer effect with ICIs is also reported.
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Antineoplásicos , Células Supressoras Mieloides , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Supressoras Mieloides/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Imunoterapia , Microambiente Tumoral , Dexametasona/farmacologiaRESUMO
Although numerous studies have focused on brain functions related to inequity aversion, few have examined its genetic basis. Here, we show the association between estimated inequity aversion and polymorphisms in three genes associated with human sociality. Non-student adult participants took part in five economic game experiments on different days. Disadvantageous inequity aversion (DIA) and advantageous inequity aversion (AIA) were calculated from behavioural responses using Bayesian estimation. We investigated the association between genetic polymorphisms in the oxytocin receptor (OXTR rs53576), arginine vasopressin receptor 1A (AVPR1A RS3) and opioid receptor mu 1 (OPRM1 rs1799971) and inequity aversion. Regarding AVPR1A RS3, participants with the SS genotype had higher AIA than those with the SL or LL genotypes, but no association was found for DIA. Moreover, we observed no aversion associations for OXTR rs53576 or OPRM1 rs1799971. The results suggest that AVPR1A plays an important role in aversion when one's own gain is greater than that of others. Our findings may provide a solid theoretical basis for future studies on the relationship between genetic polymorphisms and inequity aversion.
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Afeto , Receptores de Vasopressinas , Adulto , Humanos , Teorema de Bayes , Receptores de Vasopressinas/genética , Genótipo , Polimorfismo GenéticoRESUMO
Minimally invasive boron neutron capture therapy (BNCT) is an elegant approach for cancer treatment. The highly selective and efficient deliverability of boron agents to cancer cells is the key to maximizing the therapeutic benefits of BNCT. In addition, enhancement of the frequencies to achieve boron neutron capture reaction is also significant in improving therapeutic efficacy by providing a highly concentrated boron agent in each boron nanoparticle. As the density of the thermal neutron beam remains low, it is unable to induce high-efficiency cell destruction. Herein, we report phospholipid-coated boronic oxide nanoparticles as agents for BNCT that can provide a highly concentrated boron atom in each nanoparticle. The current system exhibited inâ vitro BNCT activity seven times higher than that of commercial boron agents. Furthermore, the system could penetrate cancer spheroids deeply, efficiently suppressing thermal neutron irradiation-induced growth.
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Terapia por Captura de Nêutron de Boro , Nanopartículas , Boro , Fosfolipídeos , Compostos de Boro/uso terapêutico , ÓxidosRESUMO
We report the generation of picosecond pulsed light at a 266â nm wavelength with an average power of 53 W. We developed a picosecond pulsed 1064â nm laser source with an average power of 261 W, a repetition rate of 1â MHz, and a pulse duration of 14 ps, using a gain-switched DFB laser diode as a seed laser and a 914â nm laser-diode-pumped Nd-doped YVO4 power amplifier. We achieved stable generation of 266â nm light with an average power of 53 W from frequency quadrupling using an LBO and a CLBO crystals. The amplified power of 261 W and the 266â nm average power of 53 W from the 914â nm pumped Nd:YVO4 amplifier are the highest ever reported, to the best of our knowledge.