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1.
Science ; 380(6650): eade0027, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37319217

RESUMO

Neuronal activity drives alterations in gene expression within neurons, yet how it directs transcriptional and epigenomic changes in neighboring astrocytes in functioning circuits is unknown. We found that neuronal activity induces widespread transcriptional up-regulation and down-regulation in astrocytes, highlighted by the identification of Slc22a3 as an activity-inducible astrocyte gene that encodes neuromodulator transporter Slc22a3 and regulates sensory processing in the mouse olfactory bulb. Loss of astrocytic Slc22a3 reduced serotonin levels in astrocytes, leading to alterations in histone serotonylation. Inhibition of histone serotonylation in astrocytes reduced the expression of γ-aminobutyric acid (GABA) biosynthetic genes and GABA release, culminating in olfactory deficits. Our study reveals that neuronal activity orchestrates transcriptional and epigenomic responses in astrocytes while illustrating new mechanisms for how astrocytes process neuromodulatory input to gate neurotransmitter release for sensory processing.


Assuntos
Astrócitos , Histonas , Bulbo Olfatório , Percepção Olfatória , Proteínas de Transporte de Cátions Orgânicos , Serotonina , Transmissão Sináptica , Animais , Camundongos , Astrócitos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Histonas/metabolismo , Proteínas de Transporte de Cátions Orgânicos/genética , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Serotonina/metabolismo , Bulbo Olfatório/metabolismo , Epigênese Genética , Percepção Olfatória/genética , Percepção Olfatória/fisiologia
2.
Nature ; 619(7971): 844-850, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380778

RESUMO

The tumour microenvironment plays an essential role in malignancy, and neurons have emerged as a key component of the tumour microenvironment that promotes tumourigenesis across a host of cancers1,2. Recent studies on glioblastoma (GBM) highlight bidirectional signalling between tumours and neurons that propagates a vicious cycle of proliferation, synaptic integration and brain hyperactivity3-8; however, the identity of neuronal subtypes and tumour subpopulations driving this phenomenon is incompletely understood. Here we show that callosal projection neurons located in the hemisphere contralateral to primary GBM tumours promote progression and widespread infiltration. Using this platform to examine GBM infiltration, we identified an activity-dependent infiltrating population present at the leading edge of mouse and human tumours that is enriched for axon guidance genes. High-throughput, in vivo screening of these genes identified SEMA4F as a key regulator of tumourigenesis and activity-dependent progression. Furthermore, SEMA4F promotes the activity-dependent infiltrating population and propagates bidirectional signalling with neurons by remodelling tumour-adjacent synapses towards brain network hyperactivity. Collectively our studies demonstrate that subsets of neurons in locations remote to primary GBM promote malignant progression, and also show new mechanisms of glioma progression that are regulated by neuronal activity.


Assuntos
Neoplasias Encefálicas , Carcinogênese , Glioma , Neurônios , Microambiente Tumoral , Humanos , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Carcinogênese/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Glioma/patologia , Glioma/fisiopatologia , Neurônios/patologia , Proliferação de Células , Sinapses , Progressão da Doença , Animais , Camundongos , Axônios , Corpo Caloso/patologia , Vias Neurais
3.
Nature ; 617(7960): 369-376, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37100909

RESUMO

Communication between neurons and glia has an important role in establishing and maintaining higher-order brain function1. Astrocytes are endowed with complex morphologies, placing their peripheral processes in close proximity to neuronal synapses and directly contributing to their regulation of brain circuits2-4. Recent studies have shown that excitatory neuronal activity promotes oligodendrocyte differentiation5-7; whether inhibitory neurotransmission regulates astrocyte morphogenesis during development is unclear. Here we show that inhibitory neuron activity is necessary and sufficient for astrocyte morphogenesis. We found that input from inhibitory neurons functions through astrocytic GABAB receptor (GABABR) and that its deletion in astrocytes results in a loss of morphological complexity across a host of brain regions and disruption of circuit function. Expression of GABABR in developing astrocytes is regulated in a region-specific manner by SOX9 or NFIA and deletion of these transcription factors results in region-specific defects in astrocyte morphogenesis, which is conferred by interactions with transcription factors exhibiting region-restricted patterns of expression. Together, our studies identify input from inhibitory neurons and astrocytic GABABR as universal regulators of morphogenesis, while further revealing a combinatorial code of region-specific transcriptional dependencies for astrocyte development that is intertwined with activity-dependent processes.


Assuntos
Astrócitos , Forma Celular , Inibição Neural , Neurônios , Receptores de GABA-B , Astrócitos/citologia , Astrócitos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Receptores de GABA-B/metabolismo , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição NFI/metabolismo , Regulação da Expressão Gênica
4.
Sci Adv ; 9(17): eade2675, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37115922

RESUMO

Glioma is a rare brain tumor with a poor prognosis. Familial glioma is a subset of glioma with a strong genetic predisposition that accounts for approximately 5% of glioma cases. We performed whole-genome sequencing on an exploratory cohort of 203 individuals from 189 families with a history of familial glioma and an additional validation cohort of 122 individuals from 115 families. We found significant enrichment of rare deleterious variants of seven genes in both cohorts, and the most significantly enriched gene was HERC2 (P = 0.0006). Furthermore, we identified rare noncoding variants in both cohorts that were predicted to affect transcription factor binding sites or cause cryptic splicing. Last, we selected a subset of discovered genes for validation by CRISPR knockdown screening and found that DMBT1, HP1BP3, and ZCH7B3 have profound impacts on proliferation. This study performs comprehensive surveillance of the genomic landscape of familial glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Glioma/genética , Glioma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Genômica , Predisposição Genética para Doença , Sequenciamento Completo do Genoma , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação a DNA/genética , Proteínas Supressoras de Tumor/genética
5.
bioRxiv ; 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36909526

RESUMO

Neuronal activity drives global alterations in gene expression within neurons, yet how it directs transcriptional and epigenomic changes in neighboring astrocytes in functioning circuits is unknown. Here we show that neuronal activity induces widespread transcriptional upregulation and downregulation in astrocytes, highlighted by the identification of a neuromodulator transporter Slc22a3 as an activity-inducible astrocyte gene regulating sensory processing in the olfactory bulb. Loss of astrocytic Slc22a3 reduces serotonin levels in astrocytes, leading to alterations in histone serotonylation. Inhibition of histone serotonylation in astrocytes reduces expression of GABA biosynthetic genes and GABA release, culminating in olfactory deficits. Our study reveals that neuronal activity orchestrates transcriptional and epigenomic responses in astrocytes, while illustrating new mechanisms for how astrocytes process neuromodulatory input to gate neurotransmitter release for sensory processing.

6.
bioRxiv ; 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36993256

RESUMO

Communication between neurons and glia plays an important role in establishing and maintaining higher order brain function. Astrocytes are endowed with complex morphologies which places their peripheral processes in close proximity to neuronal synapses and directly contributes to their regulation of brain circuits. Recent studies have shown that excitatory neuronal activity promotes oligodendrocyte differentiation; whether inhibitory neurotransmission regulates astrocyte morphogenesis during development is unknown. Here we show that inhibitory neuron activity is necessary and sufficient for astrocyte morphogenesis. We found that input from inhibitory neurons functions through astrocytic GABA B R and that its deletion in astrocytes results in a loss of morphological complexity across a host of brain regions and disruption of circuit function. Expression of GABA B R in developing astrocytes is regulated in a region-specific manner by SOX9 or NFIA and deletion of these transcription factors results in region-specific defects in astrocyte morphogenesis, which is conferred by interactions with transcription factors exhibiting region-restricted patterns of expression. Together our studies identify input from inhibitory neurons and astrocytic GABA B R as universal regulators of morphogenesis, while further revealing a combinatorial code of region-specific transcriptional dependencies for astrocyte development that is intertwined with activity-dependent processes.

7.
bioRxiv ; 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36993539

RESUMO

The tumor microenvironment (TME) plays an essential role in malignancy and neurons have emerged as a key component of the TME that promotes tumorigenesis across a host of cancers. Recent studies on glioblastoma (GBM) highlight bi-directional signaling between tumors and neurons that propagates a vicious cycle of proliferation, synaptic integration, and brain hyperactivity; however, the identity of neuronal subtypes and tumor subpopulations driving this phenomenon are incompletely understood. Here we show that callosal projection neurons located in the hemisphere contralateral to primary GBM tumors promote progression and widespread infiltration. Using this platform to examine GBM infiltration, we identified an activity dependent infiltrating population present at the leading edge of mouse and human tumors that is enriched for axon guidance genes. High-throughput, in vivo screening of these genes identified Sema4F as a key regulator of tumorigenesis and activity-dependent infiltration. Furthermore, Sema4F promotes the activity-dependent infiltrating population and propagates bi-directional signaling with neurons by remodeling tumor adjacent synapses towards brain network hyperactivity. Collectively, our studies demonstrate that subsets of neurons in locations remote to primary GBM promote malignant progression, while revealing new mechanisms of tumor infiltration that are regulated by neuronal activity.

8.
Proc Natl Acad Sci U S A ; 119(29): e2202015119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858326

RESUMO

Epigenetic dysregulation is a universal feature of cancer that results in altered patterns of gene expression that drive malignancy. Brain tumors exhibit subtype-specific epigenetic alterations; however, the molecular mechanisms responsible for these diverse epigenetic states remain unclear. Here, we show that the developmental transcription factor Sox9 differentially regulates epigenomic states in high-grade glioma (HGG) and ependymoma (EPN). Using our autochthonous mouse models, we found that Sox9 suppresses HGG growth and expands associated H3K27ac states, while promoting ZFTA-RELA (ZRFUS) EPN growth and diminishing H3K27ac states. These contrasting roles for Sox9 correspond with protein interactions with histone deacetylating complexes in HGG and an association with the ZRFUS oncofusion in EPN. Mechanistic studies revealed extensive Sox9 and ZRFUS promoter co-occupancy, indicating functional synergy in promoting EPN tumorigenesis. Together, our studies demonstrate how epigenomic states are differentially regulated in distinct subtypes of brain tumors, while revealing divergent roles for Sox9 in HGG and EPN tumorigenesis.


Assuntos
Neoplasias Encefálicas , Ependimoma , Epigênese Genética , Fatores de Transcrição SOX9 , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Ependimoma/genética , Ependimoma/patologia , Camundongos , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/fisiologia
9.
Healthcare (Basel) ; 10(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35627951

RESUMO

This study aimed to develop an emotional intelligence (EI) scale for male nursing students and investigate its associations with gender, age, religious beliefs, and father's and mother's education level. We recruited 384 male nursing students in Taiwan to construct an EI scale comprising 16 items with four factors: recognizing the emotions of others, emotional self-awareness, self-emotional expression, and self-emotional management. The scale had factor loadings of 0.64-0.80. The reliability coefficients for the subscales ranged from 0.80 to 0.84, while that for the total scale was 0.93. We also recruited 402 female nursing students for comparison. Latent multiple regression of the EI factors showed that male students had higher self-emotional expression but lower self-emotional management than females. Age was negatively associated with self-emotional management for both genders. Religious beliefs were negatively associated with emotional self-awareness in male students, and with recognizing the emotions of others in females. Father's and mother's education had no association with EI in male students; however, father's education was positively associated with all EI factors in females, and mother's education was negatively associated with recognizing the emotions of others and self-emotional expression. These results provide insight into male nursing students' EI and the background variables influencing EI.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 271: 120902, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35074672

RESUMO

The behavior of ethanol oxidation reaction on composite electrodes prepared by deposition platinum on a gold surface (Pt/Au) were studied by cyclic voltammetry and surface enhanced infrared absorption spectroscopy (SEIRAS) analysis. The results show that the Pt electrode has high oxidation activity and significant poison behavior; on the contrary, the Au electrode demonstrates low activity without a poison peak. The SEIRAS analyses reveal that both carbon monoxide (CO) and carbon dioxide (CO2) appear during anode sweeping, and the CO peak density decreases with increasing potential and finally is eliminated. During the cathodic scanning, the CO peak reappears, and the peak intensity increases with scanning cycles, demonstrating a high poison behavior and the C1 reaction route on Pt. On the Au electrode, CO2 and CO peaks were not observed; instead, an acetic acid peak appeared, indicating a C2 reaction path. For the Pt/Au composited electrodes, the electrochemical activities of the electrodes, as well as their poison behavior, increased with the deposition amount of Pt. However, the intensities of the poison peaks are smaller than those of oxidation ones; therefore, a higher tolerance to the CO poison can be achieved. For the 2 m-Pt/Au composite electrode, the activity is close to that of pure Pt, but the poison tolerance is 3 times the value of Pt.

11.
EMBO Rep ; 22(12): e52254, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34633746

RESUMO

Promyelocytic leukemia protein (PML) is a tumor suppressor possessing multiple modes of action, including induction of apoptosis. We unexpectedly find that PML promotes necroptosis in addition to apoptosis, with Pml-/- macrophages being more resistant to TNF-mediated necroptosis than wild-type counterparts and PML-deficient mice displaying resistance to TNF-induced systemic inflammatory response syndrome. Reduced necroptosis in PML-deficient cells is associated with attenuated receptor-interacting protein kinase 1 (RIPK1) activation, as revealed by reduced RIPK1[S166] phosphorylation, and attenuated RIPK1-RIPK3-MLKL necrosome complex formation. We show that PML deficiency leads to enhanced TNF-induced MAPK-activated kinase 2 (MK2) activation and elevated RIPK1[S321] phosphorylation, which suppresses necrosome formation. MK2 inhibitor treatment or MK2 knockout abrogates resistance to cell death induction in PML-null cells and mice. PML binds MK2 and p38 MAPK, thereby inhibiting p38-MK2 interaction and MK2 activation. Moreover, PML participates in autocrine production of TNF induced by cellular inhibitors of apoptosis 1 (cIAP1)/cIAP2 degradation, since PML-knockout attenuates autocrine TNF. Thus, by targeting MK2 activation and autocrine TNF, PML promotes necroptosis and apoptosis, representing a novel tumor-suppressive activity for PML.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Serina-Treonina Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Transdução de Sinais , Animais , Apoptose , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Necroptose , Fosforilação , Proteína da Leucemia Promielocítica/genética , Proteína da Leucemia Promielocítica/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Sensors (Basel) ; 21(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801852

RESUMO

In this paper, a novel self-optimizing water level monitoring methodology is proposed for smart city applications. Considering system maintenance, the efficiency of power consumption and accuracy will be important for Internet of Things (IoT) devices and systems. A multi-step measurement mechanism and power self-charging process are proposed in this study for improving the efficiency of a device for water level monitoring applications. The proposed methodology improved accuracy by 0.16-0.39% by moving the sensor to estimate the distance relative to different locations. Additional power is generated by executing a multi-step measurement while the power self-optimizing process used dynamically adjusts the settings to balance the current of charging and discharging. The battery level can efficiently go over 50% in a stable charging simulation. These methodologies were successfully implemented using an embedded control device, an ultrasonic sensor module, a LORA transmission module, and a stepper motor. According to the experimental results, the proposed multi-step methodology has the benefits of high accuracy and efficient power consumption for water level monitoring applications.

13.
Cancer Discov ; 11(9): 2200-2215, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33741710

RESUMO

More than 60% of supratentorial ependymomas harbor a ZFTA-RELA (ZRfus) gene fusion (formerly C11orf95-RELA). To study the biology of ZRfus, we developed an autochthonous mouse tumor model using in utero electroporation (IUE) of the embryonic mouse brain. Integrative epigenomic and transcriptomic mapping was performed on IUE-driven ZRfus tumors by CUT&RUN, chromatin immunoprecipitation sequencing, assay for transposase-accessible chromatin sequencing, and RNA sequencing and compared with human ZRfus-driven ependymoma. In addition to direct canonical NFκB pathway activation, ZRfus dictates a neoplastic transcriptional program and binds to thousands of unique sites across the genome that are enriched with PLAGL family transcription factor (TF) motifs. ZRfus activates gene expression programs through recruitment of transcriptional coactivators (Brd4, Ep300, Cbp, Pol2) that are amenable to pharmacologic inhibition. Downstream ZRfus target genes converge on developmental programs marked by PLAGL TF proteins, and activate neoplastic programs enriched in Mapk, focal adhesion, and gene imprinting networks. SIGNIFICANCE: Ependymomas are aggressive brain tumors. Although drivers of supratentorial ependymoma (ZFTA- and YAP1-associated gene fusions) have been discovered, their functions remain unclear. Our study investigates the biology of ZFTA-RELA-driven ependymoma, specifically mechanisms of transcriptional deregulation and direct downstream gene networks that may be leveraged for potential therapeutic testing.This article is highlighted in the In This Issue feature, p. 2113.


Assuntos
Proteínas de Ligação a DNA/genética , Ependimoma/genética , Neoplasias Supratentoriais/genética , Fator de Transcrição RelA/genética , Fatores de Transcrição/genética , Animais , Modelos Animais de Doenças , Ependimoma/patologia , Camundongos , Neoplasias Supratentoriais/patologia
14.
J Chin Med Assoc ; 79(8): 415-21, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27094504

RESUMO

BACKGROUND: Honokiol, a derivative extracted from the stem and bark of Magnolia officinalis, has been reported to have anticancer effects in hepatoma cells. Recently, it was found that honokiol acted as not only a retinoid X receptor (RXR) agonist but also as a peroxisome proliferator-activated receptor gamma (PPARγ) agonist. Additionally, honokiol is capable of activating PPARγ/RXR heterodimers synergistically in the presence of rosiglitazone in 3T3-L1 adipocyte and HLE human hepatoma cells. Furthermore, synthetic PPARγ agonist thiazolidinediones exhibited growth inhibition effects in hepatoma cells through PPARγ-dependent and PPARγ-independent pathways. However, the combined effects of treatment with honokiol and PPARγ agonist are unclear in hepatoma cells. METHODS: In this study, sulforhodamine B assay, flow cytometry, and Western blot analysis were used to examine the combined effects of honokiol and PPARγ agonist (rosiglitazone) treatment on growth inhibition in SK-Hep1 and Mahlavu hepatoma cells. RESULTS: Honokiol or rosiglitazone treatment in hepatoma cells induced growth inhibition at high dose by sulforhodamine B assay. Moreover, we found that combined treatment with honokiol and rosiglitazone showed more effective growth inhibition in hepatoma cells than treatment with honokiol or rosiglitazone alone. Also, treatment with honokiol and rosiglitazone induced cell cycle arrest in the G0/G1 phase; increased p21; and decreased cyclin D1, cyclin E1, and Rb expression in SK-Hep1 hepatoma cells. CONCLUSION: Honokiol combined with rosiglitazone showed more effective growth inhibition in hepatoma cells mediated through the regulation of G0/G1 phase-related proteins p21, cyclin D1, cyclin E1, and Rb and cell cycle progression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Lignanas/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Tiazolidinedionas/farmacologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/patologia , PPAR gama/agonistas , Rosiglitazona
15.
Biosens Bioelectron ; 22(4): 534-43, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16973344

RESUMO

The performance of molecularly imprinted polymers (MIPs) is of interest to researchers in the field of analytical chemistry, and in the pharmaceutical and food industries. Because the choice of the functional monomer(s) plays a key role in the selectivity of a MIP, the synthesis of an effective, tight-binding MIP can be difficult and time-consuming, involving the evaluation of the binding performance of MIPs of many different compositions. In this study, we report an express method combining molecular imprinting and microcontact printing techniques to prepare a polymer thin film as an artificial antibody. In addition to the microcontact printing technique, isothermal titration of monomers to proteins stamps was investigated to screen the functional monomer for MIPs. Finally, the importance of the choice of cross-linking monomers in MIPs was studied, and these studies suggest that monomers containing an optimal length PEG spacer give higher imprinting effectiveness. Several model antigens (lysozyme, ribonuclease A and myoglobin) were adsorbed on a cover glasses that were pretreated with hexamethyldisilazane (HMDS). These protein stamps were then contacted with different monomer solutions (cross-linking monomers) on a glass slide substrate. Photopolymerization yielded the molecularly imprinted polymer. This technique, analogous to microcontact printing, allows for the rapid, parallel synthesis of MIPs of different compositions, and requires very small volumes of monomers (ca. 4 microL). The technique also avoids potential solubility problems with the molecular targets. Of several cross-linking monomers screened, tetraethyleneglycol dimethacrylate (TEGDMA) gave the most selective lysozyme binding, while polyethyleneglycol 400 dimethacrylate (PEG400DMA) were most selective for ribonuclease A and myoglobin.


Assuntos
Materiais Revestidos Biocompatíveis/química , Reagentes de Ligações Cruzadas/química , Muramidase/química , Mioglobina/química , Compostos de Organossilício/química , Ribonuclease Pancreático/química , Adsorção , Teste de Materiais , Ligação Proteica , Propriedades de Superfície
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