Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 177(5): 1280-1292.e20, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31031006

RESUMO

Hyperactivity and disturbances of attention are common behavioral disorders whose underlying cellular and neural circuit causes are not understood. We report the discovery that striatal astrocytes drive such phenotypes through a hitherto unknown synaptic mechanism. We found that striatal medium spiny neurons (MSNs) triggered astrocyte signaling via γ-aminobutyric acid B (GABAB) receptors. Selective chemogenetic activation of this pathway in striatal astrocytes in vivo resulted in acute behavioral hyperactivity and disrupted attention. Such responses also resulted in upregulation of the synaptogenic cue thrombospondin-1 (TSP1) in astrocytes, increased excitatory synapses, enhanced corticostriatal synaptic transmission, and increased MSN action potential firing in vivo. All of these changes were reversed by blocking TSP1 effects. Our data identify a form of bidirectional neuron-astrocyte communication and demonstrate that acute reactivation of a single latent astrocyte synaptogenic cue alters striatal circuits controlling behavior, revealing astrocytes and the TSP1 pathway as therapeutic targets in hyperactivity, attention deficit, and related psychiatric disorders.


Assuntos
Astrócitos/metabolismo , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Comportamento Animal , Comunicação Celular , Neurônios/metabolismo , Transdução de Sinais , Sinapses/metabolismo , Animais , Astrócitos/patologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/patologia , Receptores de GABA-B/genética , Receptores de GABA-B/metabolismo , Sinapses/genética , Trombospondina 1/genética , Trombospondina 1/metabolismo , Ácido gama-Aminobutírico/genética , Ácido gama-Aminobutírico/metabolismo
2.
Immunity ; 57(6): 1274-1288.e6, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38821053

RESUMO

Severe asthma and sinus disease are consequences of type 2 inflammation (T2I), mediated by interleukin (IL)-33 signaling through its membrane-bound receptor, ST2. Soluble (s)ST2 reduces available IL-33 and limits T2I, but little is known about its regulation. We demonstrate that prostaglandin E2 (PGE2) drives production of sST2 to limit features of lung T2I. PGE2-deficient mice display diminished sST2. In humans with severe respiratory T2I, urinary PGE2 metabolites correlate with serum sST2. In mice, PGE2 enhanced sST2 secretion by mast cells (MCs). Mice lacking MCs, ST2 expression by MCs, or E prostanoid (EP)2 receptors by MCs showed reduced sST2 lung concentrations and strong T2I. Recombinant sST2 reduced T2I in mice lacking PGE2 or ST2 expression by MCs back to control levels. PGE2 deficiency also reversed the hyperinflammatory phenotype in mice lacking ST2 expression by MCs. PGE2 thus suppresses T2I through MC-derived sST2, explaining the severe T2I observed in low PGE2 states.


Assuntos
Dinoprostona , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Pulmão , Mastócitos , Camundongos Knockout , Animais , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Mastócitos/imunologia , Mastócitos/metabolismo , Dinoprostona/metabolismo , Camundongos , Interleucina-33/metabolismo , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Asma/imunologia , Asma/metabolismo , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Camundongos Endogâmicos C57BL , Inflamação/imunologia , Feminino , Masculino , Transdução de Sinais , Pneumonia/imunologia , Pneumonia/metabolismo
3.
Nat Rev Neurosci ; 21(3): 121-138, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042146

RESUMO

Astrocytes are a type of glial cell that tile the CNS. They interact with multiple cell types, including neurons, glial cells and blood vessels, and are involved or implicated in brain disorders. Progress has been made in understanding astrocytes, but the field lacks detailed information concerning how they perform their multifarious functions, and how and when they influence the operations of the neural circuits with which they interact. One recognized bottleneck to progress has been the paucity of reliable tools with which to explore astrocytes within the adult vertebrate CNS in vivo. However, improved tools for molecular, genetic, morphological and physiological assessments have been developed recently or have been adapted from their original purposes to study neurons and are now being used to systematically document and interrogate astrocyte biology in vivo. These tools, their uses and limitations, and the insights that they afford are summarized in this Review.


Assuntos
Astrócitos/citologia , Astrócitos/fisiologia , Neurociências/métodos , Animais , Sinalização do Cálcio , Eletrofisiologia/métodos , Perfilação da Expressão Gênica/métodos , Marcação de Genes/métodos , Humanos , Proteômica/métodos
4.
J Immunol ; 210(6): 709-720, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881903

RESUMO

Multistep mast cell desensitization blocks the release of mediators following IgE crosslinking with increasing doses of Ag. Although its in vivo application has led to the safe reintroduction of drugs and foods in IgE-sensitized patients at risk for anaphylaxis, the mechanisms of the inhibitory process have remained elusive. We sought to investigate the kinetics, membrane, and cytoskeletal changes and to identify molecular targets. IgE-sensitized wild-type murine (WT) and FcεRIα humanized (h) bone marrow mast cells were activated and desensitized with DNP, nitrophenyl, dust mites, and peanut Ags. The movements of membrane receptors, FcεRI/IgE/Ag, actin, and tubulin and the phosphorylation of Syk, Lyn, P38-MAPK, and SHIP-1 were assessed. Silencing SHIP-1 protein was used to dissect the SHIP-1 role. Multistep IgE desensitization of WT and transgenic human bone marrow mast cells blocked the release of ß-hexosaminidase in an Ag-specific fashion and prevented actin and tubulin movements. Desensitization was regulated by the initial Ag dose, number of doses, and time between doses. FcεRI, IgE, Ags, and surface receptors were not internalized during desensitization. Phosphorylation of Syk, Lyn, p38 MAPK, and SHIP-1 increased in a dose-response manner during activation; in contrast, only SHIP-1 phosphorylation increased in early desensitization. SHIP-1 phosphatase function had no impact on desensitization, but silencing SHIP-1 increased ß-hexoxaminidase release, preventing desensitization. Multistep IgE mast cell desensitization is a dose- and time-regulated process that blocks ß-hexosaminidase, impacting membrane and cytoskeletal movements. Signal transduction is uncoupled, favoring early phosphorylation of SHIP-1. Silencing SHIP-1 impairs desensitization without implicating its phosphatase function.


Assuntos
Actinas , Mastócitos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Animais , Humanos , Camundongos , Imunoglobulina E , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Monoéster Fosfórico Hidrolases , Receptores de IgE , Tubulina (Proteína)
5.
J Immunol ; 211(12): 1806-1813, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37870292

RESUMO

Platelets are key contributors to allergic asthma and aspirin-exacerbated respiratory disease (AERD), an asthma phenotype involving platelet activation and IL-33-dependent mast cell activation. Human platelets express the glucagon-like peptide-1 receptor (GLP-1R). GLP-1R agonists decrease lung IL-33 release and airway hyperresponsiveness in mouse asthma models. We hypothesized that GLP-1R agonists reduce platelet activation and downstream platelet-mediated airway inflammation in AERD. GLP-1R expression on murine platelets was assessed using flow cytometry. We tested the effect of the GLP-1R agonist liraglutide on lysine-aspirin (Lys-ASA)-induced changes in airway resistance, and platelet-derived mediator release in a murine AERD model. We conducted a prospective cohort study comparing the effect of pretreatment with liraglutide or vehicle on thromboxane receptor agonist-induced in vitro activation of platelets from patients with AERD and nonasthmatic controls. GLP-1R expression was higher on murine platelets than on leukocytes. A single dose of liraglutide inhibited Lys-ASA-induced increases in airway resistance and decreased markers of platelet activation and recruitment to the lung in AERD-like mice. Liraglutide attenuated thromboxane receptor agonist-induced activation as measured by CXCL7 release in plasma from patients with AERD and CD62P expression in platelets from both patients with AERD (n = 31) and nonasthmatic, healthy controls (n = 11). Liraglutide, a Food and Drug Administration-approved GLP-1R agonist for treatment of type 2 diabetes and obesity, attenuates in vivo platelet activation in an AERD murine model and in vitro activation in human platelets in patients with and without AERD. These data advance the GLP-1R axis as a new target for platelet-mediated inflammation warranting further study in asthma.


Assuntos
Asma Induzida por Aspirina , Asma , Diabetes Mellitus Tipo 2 , Humanos , Camundongos , Animais , Liraglutida/farmacologia , Liraglutida/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/uso terapêutico , Interleucina-33 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Estudos Prospectivos , Ativação Plaquetária , Aspirina/farmacologia , Inflamação , Receptores de Tromboxanos/uso terapêutico
6.
J Neurosci ; 43(45): 7463-7471, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940585

RESUMO

Astrocytes are emerging as key regulators of cognitive function and behavior. This review highlights some of the latest advances in the understanding of astrocyte roles in different behavioral domains across lifespan and in disease. We address specific molecular and circuit mechanisms by which astrocytes modulate behavior, discuss their functional diversity and versatility, and highlight emerging astrocyte-targeted treatment strategies that might alleviate behavioral and cognitive dysfunction in pathologic conditions. Converging evidence across different model systems and manipulations is revealing that astrocytes regulate behavioral processes in a precise and context-dependent manner. Improved understanding of these astrocytic functions may generate new therapeutic strategies for various conditions with cognitive and behavioral impairments.


Assuntos
Astrócitos , Disfunção Cognitiva , Humanos , Astrócitos/fisiologia , Cognição , Disfunção Cognitiva/patologia
7.
Immunology ; 172(1): 144-162, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38361249

RESUMO

Macrophages expressing group V phospholipase A2 (Pla2g5) release the free fatty acid (FFA) linoleic acid (LA), potentiating lung type 2 inflammation. Although Pla2g5 and LA increase in viral infections, their role remains obscure. We generated Pla2g5flox/flox mice, deleted Pla2g5 by using the Cx3cr1cre transgene, and activated bone marrow-derived macrophages (BM-Macs) with poly:IC, a synthetic double-stranded RNA that triggers a viral-like immune response, known Pla2g5-dependent stimuli (IL-4, LPS + IFNγ, IL-33 + IL-4 + GM-CSF) and poly:IC + LA followed by lipidomic and transcriptomic analysis. Poly:IC-activated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs had downregulation of major bioactive lipids and critical enzymes producing those bioactive lipids. In addition, AKT phosphorylation was lower in poly:IC-stimulated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs, which was not restored by adding LA to poly:IC-stimulated BM-Macs. Consistently, Pla2g5flox/flox;Cx3cr1cre/+ mice had diminished poly:IC-induced lung inflammation, including inflammatory macrophage proliferation, while challenging Pla2g5flox/flox;Cx3cr1cre/+ mice with poly:IC + LA partially restored lung inflammation and inflammatory macrophage proliferation. Finally, mice lacking FFA receptor-1 (Ffar1)-null mice had reduced poly:IC-induced lung cell recruitment and tissue macrophage proliferation, not corrected by LA. Thus, Pla2g5 contributes to poly:IC-induced lung inflammation by regulating inflammatory macrophage proliferation and LA/Ffar1-mediated lung cell recruitment and tissue macrophage proliferation.


Assuntos
Ácido Linoleico , Pneumonia , Animais , Camundongos , Proliferação de Células , Interleucina-4/metabolismo , Ácido Linoleico/metabolismo , Pulmão , Macrófagos
8.
J Immunol ; 209(12): 2293-2303, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36307120

RESUMO

Innate immune responses to innocuous Ags can either prevent or facilitate adaptive type 2 allergic inflammation, but the mechanisms are incompletely understood. We now demonstrate that macrophage UDP-specific type 6 purinergic (P2Y6) receptors selectively activate NFATC2, a member of the NFAT family, to drive an innate IL-12/IFN-γ axis that prevents type 2 allergic inflammation. UDP priming potentiated IL-12p40 production in bone marrow-derived macrophages (BMMs) stimulated by the house dust mite Dermatophagoides farinae (Df) in a P2Y6-dependent manner. Inhibitions of phospholipase C, calcium increase, and calcineurin eliminated UDP-potentiated Df-induced IL-12p40 production. UDP specifically induced nuclear translocation of NFATC2, but not NFATC1 and NFATC3, in BMMs in a P2Y6-dependent manner. UDP-potentiated IL-12p40 production by BMMs and Df-induced IL-12p40 gene expression by alveolar macrophages were abrogated in cells from Nfatc2 knockout mice. Pulmonary transplantation of wild-type but not Nfatc2 knockout macrophages increased Df-induced IL-12 production and IFN-γ expression in P2ry6 fl/fl/Cre/+ recipient mice. Finally, Nfatc2 knockout mice showed significantly increased indices of type 2 immunopathology in response to Df challenge, similar to P2ry6 fl/fl/Cre/+ mice. Thus, macrophage P2Y6 receptor signaling selectively utilizes NFATC2 to potentiate an innate IL-12/IFN-γ axis, a potential mechanism that protects against inappropriate type 2 immune responses.


Assuntos
Alveolite Alérgica Extrínseca , Fatores de Transcrição NFATC , Receptores Purinérgicos P2 , Animais , Camundongos , Alveolite Alérgica Extrínseca/metabolismo , Inflamação/metabolismo , Subunidade p40 da Interleucina-12/metabolismo , Macrófagos , Camundongos Knockout , Difosfato de Uridina/metabolismo , Receptores Purinérgicos P2/metabolismo , Fatores de Transcrição NFATC/metabolismo
9.
Cereb Cortex ; 32(3): 520-527, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-34297816

RESUMO

The mammalian cerebral cortex is characterized by a 6-layer structure, and proper neuronal migration is critical for its formation. Cyclin-dependent kinase 5 (Cdk5) has been shown to be a critical kinase for neuronal migration. Several Cdk5 substrates have been suggested to be involved in ordered neuronal migration. However, in vivo loss-of-function studies on the function of Cdk5 phosphorylation substrates in neuronal migration in the developing cerebral cortex have not been reported. In this study, we demonstrated that Cdk5-mediated phosphorylation of collapsing mediator protein (CRMP) 2 is critical for neuronal migration in the developing cerebral cortex with redundant functions of CRMP1 and CRMP4. The cerebral cortices of triple-mutant CRMP1 knock-out (KO); CRMP2 knock-in (KI)/KI; and CRMP4 KO mice showed disturbed positioning of layers II-V neurons in the cerebral cortex. Further experiments using bromodeoxyuridine birthdate-labeling and in utero electroporation implicated radial migration defects in cortical neurons. Ectopic neurons were detected around the CA1 region and dentate gyrus in CRMP1 KO; CRMP2 KI/KI; and CRMP4 KO mice. These results suggest the importance of CRMP2 phosphorylation by Cdk5 and redundancy of CRMP1 and CRMP4 in proper neuronal migration in the developing cerebral cortex and hippocampus.


Assuntos
Quinase 5 Dependente de Ciclina , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurogênese , Animais , Córtex Cerebral/metabolismo , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Hipocampo/metabolismo , Mamíferos/metabolismo , Camundongos , Neurônios/metabolismo , Fosforilação
10.
Br J Haematol ; 196(3): 764-768, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34816427

RESUMO

Approximately 20% of patients with transient abnormal myelopoiesis (TAM) die due to hepatic or multiorgan failure. To identify potential new treatments for TAM, we performed in vitro drug sensitivity testing (DST) using the peripheral blood samples of eight patients with TAM. DST screened 41 agents for cytotoxic properties against TAM blasts. Compared with the reference samples of healthy subjects, TAM blasts were more sensitive to glucocorticoids, the mitogen-activated protein kinase kinase (MAP2K) inhibitor trametinib, and cytarabine. Our present results support the therapeutic potential of glucocorticoids and the role of the RAS/MAP2K signalling pathway in TAM pathogenesis.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Reação Leucemoide/tratamento farmacológico , Mielopoese/efeitos dos fármacos , Adulto , Antineoplásicos/uso terapêutico , Biomarcadores , Técnicas de Cultura de Células , Células Cultivadas , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Ensaios de Triagem em Larga Escala , Humanos , Imuno-Histoquímica , Reação Leucemoide/etiologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
11.
J Allergy Clin Immunol ; 148(1): 195-208.e5, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33285161

RESUMO

BACKGROUND: The 3 cysteinyl leukotrienes (cysLTs), leukotriene (LT) C4 (LTC4), LTD4, and LTE4, have different biologic half-lives, cellular targets, and receptor specificities. CysLT2R binds LTC4 and LTD4in vitro with similar affinities, but it displays a marked selectivity for LTC4in vivo. LTC4, but not LTD4, strongly potentiates allergen-induced pulmonary eosinophilia in mice through a CysLT2R-mediated, platelet- and IL-33-dependent pathway. OBJECTIVE: We sought to determine whether LTD4 functionally antagonizes LTC4 signaling at CysLT2R. METHODS: We used 2 different in vivo models of CysLT2R-dependent immunopathology, as well as ex vivo activation of mouse and human platelets. RESULTS: LTC4-induced CD62P expression; HMGB1 release; and secretions of thromboxane A2, CXCL7, and IL-33 by mouse platelets were all were blocked by a selective CysLT2R antagonist and inhibited by LTD4. These effects did not depend on CysLT1R. Inhaled LTD4 blocked LTC4-mediated potentiation of ovalbumin-induced eosinophilic inflammation; recruitment of platelet-adherent eosinophils; and increases in IL-33, IL-4, IL-5, and IL-13 levels in lung tissue. In contrast, the effect of administration of LTE4, the preferred ligand for CysLT3R, was additive with LTC4. The administration of LTD4 to Ptges-/- mice, which display enhanced LTC4 synthesis similar to that in aspirin-exacerbated respiratory disease, completely blocked the physiologic response to subsequent lysine-aspirin inhalation challenges, as well as increases in levels of IL-33, type 2 cytokines, and biochemical markers of mast cell and platelet activation. CONCLUSION: The conversion of LTC4 to LTD4 may limit the duration and extent of potentially deleterious signaling through CysLT2R, and it may contribute to the therapeutic properties of desensitization to aspirin in aspirin-exacerbated respiratory disease.


Assuntos
Plaquetas/imunologia , Leucotrieno C4/imunologia , Leucotrieno D4/imunologia , Pulmão/imunologia , Ativação Plaquetária/imunologia , Animais , Asma/imunologia , Cisteína/imunologia , Citocinas/imunologia , Leucotrieno E4/imunologia , Leucotrienos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Eosinofilia Pulmonar/imunologia , Receptores de Leucotrienos/imunologia
12.
Biochem Biophys Res Commun ; 568: 167-173, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34237486

RESUMO

Lysophosphatidic acid (LPA) plays a critical role in developing and maintaining chronic pain in various animal models. Previous studies have reported that cytosolic and calcium-independent phospholipase A2 (PLA2) is involved in the LPA receptor-mediated amplification of LPA production in the spinal dorsal horn (SDH) after nerve injury, while the involvement of secreted PLA2 (sPLA2) remains unclear. The present study revealed that only sPLA2 -III among 11 species of PLA2 showed a significant upregulation of gene expression in the SDH. Intraspinal injection of adeno-associated virus-miRNA targeting sPLA2-III prevented hyperalgesia and unique hypoalgesia in mice treated with partial sciatic nerve ligation. In addition, intrathecal treatment with antisense oligodeoxynucleotide or siRNA targeting sPLA2-III significantly reversed the established thermal hyperalgesia. In the high-throughput screening of sPLA2-III inhibitors from the chemical library, we identified two hit compounds. Through in vitro characterization of PLA2 inhibitor profiles and in vivo assessment of the anti-hyperalgesic effects of known PLA2 inhibitors as well as hit compounds, sPLA2-III was found to be a novel therapeutic target molecule for the treatment of Neuropathic pain.


Assuntos
Fosfolipases A2 do Grupo III/metabolismo , Neuralgia/metabolismo , Animais , Expressão Gênica , Técnicas de Silenciamento de Genes , Fosfolipases A2 do Grupo III/genética , Masculino , Camundongos Endogâmicos C57BL , Neuralgia/genética , Neuralgia/terapia , Regulação para Cima
13.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652591

RESUMO

Repressor element-1 (RE-1) or neural restrictive silencer element (NRSE) bound with a zinc finger transcription repressor, RE-1 silencing transcription factor (REST, also known as neural restrictive silencer factor, NRSF) has been identified as a fundamental repressor element in many genes, including neuronal genes. Genes regulated by REST/NRSF regulate multifaceted neuronal phenotypes, and their defects in the machinery cause neuropathies, disorders of neuron activity), autism and so on. In REST repressions, the N-terminal repressor domain recruits Sin3B via its paired amphipathic helix 1 (PAH1) domain, which plays an important role as a scaffold for histone deacetylase 1 and 2. This machinery has a critical role in maintaining neuronal robustness. In this study, in order to establish protein-protein interaction assays mimicking a binding surface between Sin3B and REST, we selected important amino acids from structural information of the PAH1/REST complex and then tried to reconstitute it using recombinant short peptides derived from PAH1/REST. Initially, we validated whether biotinylated REST interacts with glutathione S-transferase (GST)-tagged PAH1 and whether another PAH1 peptide (PAH1-FLAG) competitively binds with biotinylated REST using surface plasmon resonance (SPR). We observed a direct interaction and competitive binding of two PAH1 peptides. Secondly, in order to establish a high-throughput and high-dynamic-range assay, we utilized an easily performed novel time-resolved fluorescence energy transfer (TR-FRET) assay, and closely monitored this interaction. Finally, we succeeded in establishing a novel high-quality TR-FRET assay and a novel interaction assay based on SPR.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Proteínas Repressoras/química , Ressonância de Plasmônio de Superfície , Humanos , Ligação Proteica , Proteínas Repressoras/metabolismo
14.
Genes Cells ; 24(1): 31-40, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30375127

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by slow and progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc). Levodopa (l-Dopa), the current main treatment for PD, supplies dopamine, but it does not prevent neurodegeneration. There is thus no promising remedy for PD. Recent in vitro study showed the increase in the phosphorylation levels of Collapsin Response Mediator Protein 2 (CRMP2) is involved in dopaminergic axon degeneration. In the present study, we report elevation of CRMP2 phosphorylation in dopaminergic neurons in SNc after challenge with the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a common model for PD. Genetic suppression of CRMP2 phosphorylation by mutation of the obligatory Cyclin-dependent kinase 5 (Cdk5)-targeted serine-522 site prevented axonal degradation in the nigrostriatal pathway of transgenic mice. As a result, the degree of MPTP-induced motor impairment in the rotarod test was suppressed. These results suggest that suppression of CRMP2 phosphorylation may be a novel therapeutic target for PD.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Supressão Genética , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/análogos & derivados , Animais , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Microglia/patologia , Atividade Motora , Neostriado/patologia , Degeneração Neural/patologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Fosforilação , Substância Negra/patologia
15.
Mar Drugs ; 18(3)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183121

RESUMO

Toxoplasma gondii is a major protozoan parasite and infects human and many other warm-blooded animals. The infection leads to Toxoplasmosis, a serious issue in AIDS patients, organ transplant recipients and pregnant women. Neospora caninum, another type of protozoa, is closely related to Toxoplasma gondii. Infections of the protozoa in animals also causes serious diseases such as Encephalomyelitis and Myositis-Polyradiculitis in dogs or abortion in cows. Both Toxoplasma gondii and Neospora caninum have similar nucleoside triphosphate hydrolases (NTPase), NcNTPase and TgNTPase-I in Neospora caninum and Toxoplasma gondii, respectively. These possibly play important roles in propagation and survival. Thus, we targeted the enzymes for drug discovery and tried to establish a novel high-standard assay by a combination of original biochemical enzyme assay and fluorescent assay to determine ADP content. We then validated whether or not it can be applied to high-throughput screening (HTS). Then, it fulfilled criterion to carry out HTS in both of the enzymes. In order to identify small molecules having inhibitory effects on the protozoan enzyme, we also performed HTS using two synthetic compound libraries and an extract library derived from marine bacteria and then, identified 19 compounds and 6 extracts. Nagasaki University collected many extracts from over 18,000 marine bacteria found in local Omura bay, and continues to compile an extensive collection of synthetic compounds from numerous drug libraries established by Japanese chemists.


Assuntos
Medições Luminescentes , Neospora/enzimologia , Nucleosídeo-Trifosfatase/análise , Toxoplasma/enzimologia , Animais , Humanos
16.
Mar Drugs ; 18(1)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963531

RESUMO

Very recently, the immunotherapies against cancer, autoimmune diseases, and infection have been feasible and promising. Thus, we have examined the possibility whether or not human gamma delta T cells can be applied for the novel immunotherapies. We previously established the cells stably maintaining NFkB-driven human secreted embryonic alkaline phosphatase (SEAP) expression. The cells can be used to determine the transcription activity of NFkB with high-standard dynamic range and accuracy. Because IL-18 is a kind of cytokines that enhances cytotoxicity and activity of human gamma delta T cells through NFkB activation, we have focused on the activity and signaling of IL-18. In this study, we modified the previous reporter cell that can determine the transcription activity of NFkB to express two subunits consisted of human IL-18 receptor. The modified cells secreted SEAP in response to treatment with human recombinant IL-18 in a concentration-dependent manner. We also observed the concentration-dependently enhancement of NFkB activity in the cells treated with mouse recombinant IL-18 although the affinity was lower compared to human recombinant IL-18. We also previously established the cells stably expressing and secreting human recombinant IL-18 and then validated whether or not the conditioned medium from the cells activate NFkB transcription activity using this assay. Our university has kept collecting many extracts from over 18,000 marine bacteria in our local sea around Omura bay-fungi, plants for Chinese herbal medicine, and so on-and also have kept gathering synthetic compounds from many Japanese chemists as drug libraries. Finally, in order to identify drugs mimicking IL-18 biological activity or possessing inhibitory effects on IL-18-induced NFkB, we demonstrated drug screening using number of extracts derived from marine bacteria and synthetic compounds.


Assuntos
Interleucina-18/metabolismo , Transdução de Sinais/fisiologia , Organismos Aquáticos/metabolismo , Bactérias/metabolismo , Bioensaio/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Humanos , NF-kappa B/metabolismo
17.
Pediatr Int ; 62(5): 556-561, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31955471

RESUMO

BACKGROUND: Genetic testing has enabled the diagnosis of multiple congenital anomalies and/or intellectual disabilities. However, because of the phenotypic variability in these disorders, selection of an appropriate genetic test can be difficult and complex. For clinical examination, particularly in clinical facilities, a simple and standardized system is needed. METHODS: We compared microarray comparative genomic hybridization and clinical exome sequencing with regard to diagnostic yield, cost, and time required to reach a definitive diagnosis. After first performing G-banding for 200 patients with multiple congenital anomalies and/or intellectual disability, as a subsequent genetic test, microarray and clinical exome sequencing were compared with regard to diagnostic yield, cost, and time required. RESULTS: There was no obvious difference in the diagnostic rate between the two methods; however, clinical exome sequencing was superior in terms of cost and time. In addition, clinical exome sequencing could sufficiently identify copy number variants, and even smaller copy number variants could be identified. CONCLUSIONS: Clinical exome sequencing should be implemented earlier as a genetic test for undiagnosed patients with multiple congenital anomalies and/or intellectual disabilities. Our results can be used to establish inspection methods in clinical facilities.


Assuntos
Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Testes Genéticos/métodos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa/economia , Hibridização Genômica Comparativa/métodos , Variações do Número de Cópias de DNA , Testes Genéticos/economia , Humanos , Análise em Microsséries/métodos , Sequenciamento do Exoma/economia , Sequenciamento do Exoma/métodos
18.
Biochem Biophys Res Commun ; 514(4): 1037-1039, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31097218

RESUMO

Axonal degeneration occurs in patients with various neurological diseases and traumatic nerve injuries, and Wallerian degeneration is a phenomenon in the prototypical axonal degradation that is observed after injury. Collapsin response mediator protein 2 (CRMP2) is phosphorylated by glycogen synthase kinase 3ß (GSK3ß), and it is involved in Wallerian degeneration after optic nerve injury. We previously developed a CRMP2 knock-in (CRMP2 KI) mouse line, in which CRMP2 phosphorylation by GSK3ß is inhibited; however, Wallerian degeneration in CRMP2 KI mice has not yet been examined. In this study, we examined whether Wallerian degeneration of the optic nerve is suppressed in CRMP2 KI mice. Using one eye removal model, we compared Wallerian degeneration of the optic nerve based on histological and biochemical analyses. Our experimental results indicated that the genetic inhibition of CRMP2 phosphorylation delays Wallerian degeneration after optic nerve injury.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Traumatismos do Nervo Óptico/genética , Degeneração Walleriana/genética , Animais , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Semaforina-3A/farmacologia
19.
Rinsho Ketsueki ; 60(7): 779-784, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31391366

RESUMO

Aplastic anemia (AA), a hematopoietic disorder characterized by hypocellular bone marrow, is caused by immunologically-mediated hematopoietic stem cell injury. Viral infection is hypothesized as the underlying cause of hepatitis-associated AA, although its mechanism is still unclear. This report describes a case of AA following suspected drug-induced liver injury (DILI). An 18-year-old man developed severe liver dysfunction after taking oral over-the-counter drugs. The patient was diagnosed with suspected DILI based on drug-induced lymphocyte stimulation test and liver biopsy results. Although liver dysfunction improved after a course of steroid pulse therapy and liver supporting therapy, the man gradually developed pancytopenia within 3 months of DILI diagnosis, prompting the diagnosis of AA following DILI. Paroxysmal nocturnal hemoglobinuria-type cells were detected by high-sensitivity flow cytometry. Immunosuppressive therapy with antithymocyte globulin and cyclosporin was administered, with pancytopenia improvement. To the best of our knowledge, this is the first report in the literature with a case of AA following DILI, and we believe it is important for evaluating the pathogenesis of drug-induced and hepatitis-associated AA.


Assuntos
Anemia Aplástica/etiologia , Doença Hepática Induzida por Substâncias e Drogas/complicações , Adolescente , Anemia Aplástica/tratamento farmacológico , Soro Antilinfocitário/uso terapêutico , Ciclosporina/uso terapêutico , Hemoglobinúria Paroxística , Humanos , Imunossupressores/uso terapêutico , Masculino
20.
J Hum Genet ; 63(11): 1185-1188, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30108319

RESUMO

A 15q11.2 microdeletion (BP1-BP2) is associated with congenital heart diseases (CHDs), developmental delay, and epilepsy. This deletion co-occurs with CHD in 20-30% patients, but a familial case of CHD and a 15q11.2 deletion has not been identified. Here we report the first familial (three siblings) case of total anomalous pulmonary venous return associated with 15q11.2 deletion. Array comparative genomic hybridization identified a ~395 kb deletion at 15q11.2 in patient 1. This deletion was confirmed by fluorescence in situ hybridization in patients 1 and 3 and their asymptomatic father. No deleterious mutation was identified by proband-only exome sequencing of patient 1. One healthy sibling and their mother did not carry the deletion. This deletion is often inherited from asymptomatic parents with an estimated low penetrance of 10.4%. Conversely, we observed high penetrance of this deletion, but secondary copy-number variants or pathogenic variants were not detected in this family.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Síndrome de Cimitarra/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Síndrome de Cimitarra/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA