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











Base de dados
Intervalo de ano de publicação
1.
Curr Neurovasc Res ; 21(2): 177-183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482623

RESUMO

BACKGROUND: Cerebral Cavernous Malformation (CCM) is one of the most common types of vascular malformation of the central nervous system. Intracerebral hemorrhage, seizures, and lesional growth are the main clinical manifestations. Natural history studies have tried to identify many risk factors; however, the clinical course remains highly unpredictable. OBJECTIVE: Here, we have analyzed a multicenter CCM cohort looking for the differential clinical data regarding the patients harboring supra and/or infratentorial cavernous malformations in order to better understand risk factors involved in the anatomical location of the unique neurosurgical disease. METHODS: We have presented a multicenter, Propensity Score Matched (PSM), case-control study including 149 consecutive CCM cases clinically evaluated from May 2017 to December 2022 from three different neurosurgical centers. Epidemiological data were defined at each clinical assessment. Logistic regression was used to identify the independent contribution of each possible risk factor to the bleeding risk. To balance baseline covariates between patients with and without symptoms, and specifically between those with and without symptomatic bleeding, we used a PSM strategy. The Kaplan-Meier curve was drawn to evaluate if patients with infratentorial lesions had a greater chance of bleeding earlier in their life. RESULTS: The presence of infratentorial lesions was a risk factor in the multivariate analysis comparing the bleeding risk with pure asymptomatic individuals (OR: 3.23, 95% CI 1.43 - 7.26, P = 0.005). Also, having an infratentorial CCM was a risk factor after PSM (OR: 4.56, 95% CI 1.47 - 14.10, P = 0.008). The presence of an infratentorial lesion was related to precocity of symptoms when the time to first bleed was compared to all other clinical presentations in the overall cohort (P = 0.0328) and in the PSM group (P = 0.03). CONCLUSION: Here, we have provided some evidence that infratentorial cerebral cavernous malformation may have a more aggressive clinical course, being a risk factor for symptomatic haemorrhage and precocity of bleeding.


Assuntos
Hemorragia Cerebral , Hemangioma Cavernoso do Sistema Nervoso Central , Pontuação de Propensão , Humanos , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Masculino , Feminino , Fatores de Risco , Estudos de Casos e Controles , Adulto , Pessoa de Meia-Idade , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/etiologia , Adulto Jovem , Adolescente , Criança , Idoso
2.
Transl Stroke Res ; 15(2): 411-421, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-36723700

RESUMO

Cerebral cavernous malformation (CCM) is a vascular disease that affects the central nervous system, which familial form is due to autosomal dominant mutations in the genes KRIT1(CCM1), MGC4607(CCM2), and PDCD10(CCM3). Patients affected by the PDCD10 mutations usually have the onset of symptoms at an early age and a more aggressive phenotype. The aim of this study is to investigate the molecular mechanism involved with CCM3 disease pathogenesis. Herein, we report two typical cases of CCM3 phenotype and compare the clinical and neuroradiological findings with five patients with a familial form of KRIT1 or CCM2 mutations and six patients with a sporadic form. In addition, we evaluated the PDCD10 gene expression by qPCR and developed a bioinformatic pipeline to understand the structural changes of mutations. The two CCM3 patients had an early onset of symptoms and a high lesion burden. Furthermore, the sequencing showed that Patient 1 had a frameshift mutation in c.222delT; p.(Asn75Thrfs*14) that leads to lacking the last 124 C-terminal amino acids on its primary structure and Patient 2 had a variant on the splicing site region c.475-2A > G. The mRNA expression was fourfold lower in both patients with PDCD10 mutation. Using in silico analysis, we identify that the frameshift mutation transcript lacks the C-terminal FAT-homology domain compared to the wild-type PDCD10 and preserves the N-terminal dimerization domain. The two patients studied here allow estimating the potential impact of mutations in clinical interpretation as well as support to better understand the mechanism and pathogenesis of CCM3.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Humanos , Sistema Nervoso Central , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Mutação/genética , Fenótipo , Proteínas Proto-Oncogênicas/genética
3.
J Neurochem ; 162(6): 501-513, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35797221

RESUMO

Glioblastoma is the most common and malignant type of primary brain tumor. Previous studies have shown that alterations in centrosome amplification and its components are frequently found in treatment-resistant tumors and may be associated with tumor progression. A centrosome protein essential for centrosome biogenesis is the centromere protein J (CENPJ), known to control the proliferation of neural progenitors and hepatocarcinoma cells, and also neuronal migration. However, it remains unknown the role of CENPJ in glioblastoma. Here we show that CENPJ is overexpressed in human glioblastoma cell lines in comparison to human astrocytes. Using bioinformatics analysis, we find that high Cenpj expression is associated with poor prognosis in glioma patients. Examining Cenpj loss of function in glioblastoma by siRNA transfection, we find impairments in cell proliferation and migration. Using a Cenpj mutant version with the deleted PN2-3 or TCP domain, we found that a conserved PN2-3 region is required for glioblastoma migration. Moreover, Cenpj downregulation modulates glioblastoma morphology resulting in microtubules stabilization and actin filaments depolymerization. Altogether, our findings indicate that CENPJ controls relevant aspects of glioblastoma progression and might be a target for therapeutic intervention and a biomarker for glioma malignancy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Centrômero/metabolismo , Centrômero/patologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioma/metabolismo , Humanos
4.
Curr Neurovasc Res ; 18(2): 172-180, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34082682

RESUMO

BACKGROUND: Cerebral Cavernous Malformations (CCM) predispose patients to a lifetime risk of seizures and symptomatic hemorrhage. Only a small percentage of people affected will develop clinical symptoms and the molecular mechanisms underlying lesional activity remain unclear. We analyzed a panel of Single Nucleotide Polymorphisms (SNPs) in CCM patients. We looked for plasmatic inflammatory cytokines, checking for a pattern of plasma expression heterogeneity and any correlation with genetic variations identified with different CCM clinical phenotypes. METHODS: This was a case-control study from a long-term follow-up cohort including 23 CCM patients, of which 16 were symptomatic, and 7 were asymptomatic. A 200-SNP panel was considered through next-generation sequencing and 18 different plasma molecules were assessed through a suspension array system. RESULTS: Fcγ receptor IIa rs1801274 (FCGR2A) and protein tyrosine phosphatase non-receptor type 2 rs72872125 PTPN2 were statistically different between groups. Patients who had a combination of the presence of FCGR2A and the absence of PTPN2 also had symptoms earlier in life. The combination of genetic polymorphisms and serum level of GM-CSF showed the best diagnostic biomarker to distinguish symptomatic patients as formulated: [0.296*(FCGR2A)] + [-0.788*(PTPN2)] + [-0.107*(GM-CSF)]. CONCLUSION: We have shown that SNPs in inflammation genes might be related to a symptomatic phenotype in CCM. We also demonstrated that a formula based on two of these polymorphisms (FCGR2A+ and PTPN2+) is possibly capable of predicting a symptomatic phenotype during a patient's lifetime.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Receptores de IgG/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Neurochem ; 150(2): 138-157, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31009074

RESUMO

Parkinson's disease (PD) is characterized by selective death of dopaminergic neurons in the substantia nigra, degeneration of the nigrostriatal pathway, increases in glutamatergic synapses in the striatum and aggregation of α-synuclein. Evidence suggests that oligomeric species of α-synuclein (αSO) are the genuine neurotoxins of PD. Although several studies have supported the direct neurotoxic effects of αSO on neurons, their effects on astrocytes have not been directly addressed. Astrocytes are essential to several steps of synapse formation and function, including secretion of synaptogenic factors, control of synaptic elimination and stabilization, secretion of neural/glial modulators, and modulation of extracellular ions, and neurotransmitter levels in the synaptic cleft. Here, we show that αSO induced the astrocyte reactivity and enhanced the synaptogenic capacity of human and murine astrocytes by increasing the levels of the known synaptogenic molecule transforming growth factor beta 1 (TGF-ß1). Moreover, intracerebroventricular injection of αSO in mice increased the number of astrocytes, the density of excitatory synapses, and the levels of TGF-ß1 in the striatum of injected animals. Inhibition of TGF-ß1 signaling impaired the effect of the astrocyte-conditioned medium on glutamatergic synapse formation in vitro and on striatal synapse formation in vivo, whereas addition of TGF-ß1 protected mesencephalic neurons against synapse loss triggered by αSO. Together, our data suggest that αSO have important effects on astrocytic functions and describe TGF-ß1 as a new endogenous astrocyte-derived molecule involved in the increase in striatal glutamatergic synaptic density present in early stages of PD. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Cover Image for this issue: doi: 10.1111/jnc.14514.


Assuntos
Astrócitos/metabolismo , Transtornos Parkinsonianos/metabolismo , Sinapses/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , alfa-Sinucleína/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Neurogênese/fisiologia , Transdução de Sinais/fisiologia
6.
Mol Neurobiol ; 55(8): 6816-6833, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29349577

RESUMO

Glioblastoma (GBM) is the most common and aggressive malignant primary brain tumor and still lacks effective therapeutic strategies. It has already been shown that old drugs like sulfasalazine (SAS) and valproic acid (VPA) present antitumoral activities in glioma cell lines. SAS has also been associated with a decrease of intracellular glutathione (GSH) levels through a potent inhibition of xc- glutamate/cystine exchanger leading to an antioxidant deprotection. In the same way, VPA was recently identified as a histone deacetylase (HDAT) inhibitor capable of activating tumor suppression genes. As both drugs are widely used in clinical practice and their profile of adverse effects is well known, the aim of our study was to investigate the effects of the combined treatment with SAS and VPA in GBM cell lines. We observed that both drugs were able to reduce cell viability in a dose-dependent manner and the combined treatment potentiated these effects. Combined treatment also increased cell death and inhibited proliferation of GBM cells, while having no effect on human and rat cultured astrocytes. Also, we observed high protein expression of the catalytic subunit of xc- in all the examined GBM cell lines, and treatment with SAS blocked its activity and decreased intracellular GSH levels. Noteworthy, SAS but not VPA was also able to reduce the [14C]-ascorbate uptake. Together, these data indicate that SAS and VPA exhibit a substantial effect on GBM cell's death related to an intracellular oxidative response imbalance, making this combination of drugs a promising therapeutic strategy.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Espaço Intracelular/metabolismo , Sulfassalazina/farmacologia , Ácido Valproico/farmacologia , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Ácido Ascórbico/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Glutationa/metabolismo , Humanos , Mesoderma/efeitos dos fármacos , Mesoderma/patologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Oxirredução , Ratos , Fatores de Tempo
7.
Sci Rep ; 7: 45091, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28345587

RESUMO

Astrocytes play a critical role in the development and homeostasis of the central nervous system (CNS). Astrocyte dysfunction results in several neurological and degenerative diseases. However, a major challenge to our understanding of astrocyte physiology and pathology is the restriction of studies to animal models, human post-mortem brain tissues, or samples obtained from invasive surgical procedures. Here, we report a protocol to generate human functional astrocytes from cerebral organoids derived from human pluripotent stem cells. The cellular isolation of cerebral organoids yielded cells that were morphologically and functionally like astrocytes. Immunolabelling and proteomic assays revealed that human organoid-derived astrocytes express the main astrocytic molecular markers, including glutamate transporters, specific enzymes and cytoskeletal proteins. We found that organoid-derived astrocytes strongly supported neuronal survival and neurite outgrowth and responded to ATP through transient calcium wave elevations, which are hallmarks of astrocyte physiology. Additionally, these astrocytes presented similar functional pathways to those isolated from adult human cortex by surgical procedures. This is the first study to provide proteomic and functional analyses of astrocytes isolated from human cerebral organoids. The isolation of these astrocytes holds great potential for the investigation of developmental and evolutionary features of the human brain and provides a useful approach to drug screening and neurodegenerative disease modelling.


Assuntos
Astrócitos/citologia , Córtex Cerebral/citologia , Crescimento Neuronal , Organoides/citologia , Animais , Astrócitos/metabolismo , Sinalização do Cálcio , Células Cultivadas , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteoma/genética , Proteoma/metabolismo
8.
World Neurosurg ; 86: 514.e19-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26548819

RESUMO

BACKGROUND: Cavernous malformation (CM) is a vascular malformation found in the encephalic parenchyma, spinal cord, nerve roots, and extraneural tissue. CM in the trigeminal distribution is exquisitely uncommon and its biological behavior not completely understood. The clinical picture might be diverse, depending on the affected sector of the trigeminal architecture, and literature debating its pathobiology is scarce. CASE DESCRIPTION: We describe a case of 56-year-old woman who presented with left trigeminal neuralgia and a rapidly growing cavernous malformation of the entire distribution of the fifth nerve. The clinical picture evolved to a progressive gait ataxia and follow-up neuroimaging showed a large intracranial mass leading to a brainstem compression. After microsurgical resection, the mass proved to be a typical CM of the trigeminal root. CONCLUSION: We present an uncommonly aggressive progression of a CM of the trigeminal root, Gasserian ganglion, and cavernous sinus evolving to severe brainstem compression. The documentation of this unique case as well as its management is presented is discussed.


Assuntos
Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico , Neuralgia do Trigêmeo/etiologia , Neoplasias Encefálicas/cirurgia , Feminino , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Humanos , Pessoa de Meia-Idade , Neuralgia do Trigêmeo/diagnóstico , Neuralgia do Trigêmeo/terapia
9.
PLoS One ; 8(1): e55605, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23383241

RESUMO

Connective-tissue growth factor (CTGF/CCN2) is a matricellular-secreted protein involved in complex processes such as wound healing, angiogenesis, fibrosis and metastasis, in the regulation of cell proliferation, migration and extracellular matrix remodeling. Glioblastoma (GBM) is the major malignant primary brain tumor and its adaptation to the central nervous system microenvironment requires the production and remodeling of the extracellular matrix. Previously, we published an in vitro approach to test if neurons can influence the expression of the GBM extracellular matrix. We demonstrated that neurons remodeled glioma cell laminin. The present study shows that neurons are also able to modulate CTGF expression in GBM. CTGF immnoreactivity and mRNA levels in GBM cells are dramatically decreased when these cells are co-cultured with neonatal neurons. As proof of particular neuron effects, neonatal neurons co-cultured onto GBM cells also inhibit the reporter luciferase activity under control of the CTGF promoter, suggesting inhibition at the transcription level. This inhibition seems to be contact-mediated, since conditioned media from embryonic or neonatal neurons do not affect CTGF expression in GBM cells. Furthermore, the inhibition of CTGF expression in GBM/neuronal co-cultures seems to affect the two main signaling pathways related to CTGF. We observed inhibition of TGFß luciferase reporter assay; however phopho-SMAD2 levels did not change in these co-cultures. In addition levels of phospho-p44/42 MAPK were decreased in co-cultured GBM cells. Finally, in transwell migration assay, CTGF siRNA transfected GBM cells or GBM cells co-cultured with neurons showed a decrease in the migration rate compared to controls. Previous data regarding laminin and these results demonstrating that CTGF is down-regulated in GBM cells co-cultured with neonatal neurons points out an interesting view in the understanding of the tumor and cerebral microenvironment interactions and could open up new strategies as well as suggest a new target in GBM control.


Assuntos
Comunicação Celular , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Glioblastoma/metabolismo , Neurônios/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Técnicas de Cocultura , Fator de Crescimento do Tecido Conjuntivo/genética , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Cultura Primária de Células , Regiões Promotoras Genéticas , Ratos , Transdução de Sinais , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Ativação Transcricional , Fator de Crescimento Transformador beta/metabolismo
10.
Curr Top Med Chem ; 12(19): 2082-93, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23167797

RESUMO

Glioblastoma (GBM) is considered incurable due to its resistance to current cancer treatments. So far, all clinically available alternatives for treating GBM are limited, evoking the development of novel treatment strategies that can more effectively manage these tumors. Extensive effort is being dedicated to characterize the molecular basis of GBM resistance to chemotherapy and to explore novel therapeutic procedures that may improve overall survival. Cytolysins are toxins that form pores in target cell membranes, modifying ion homeostasis and leading to cell death. These pore-forming toxins might be used, therefore, to enhance the efficiency of conventional chemotherapeutic drugs, facilitating their entrance into the cell. In this study, we show that a non-cytotoxic concentration of equinatoxin II (EqTx-II), a pore-forming toxin from the sea anemone Actinia equina, potentiates the cytotoxicity induced by temozolomide (TMZ), a first-line GBM treatment, and by etoposide (VP-16), a second- or third-line GBM treatment. We also suggest that this effect is selective to GBM cells and occurs via PI3K/Akt pathway inhibition. Finally, Magnetic resonance imaging (MRI) revealed that a non-cytotoxic concentration of EqTx-II potentiates the VP-16-induced inhibition of GBM growth in vivo. These combined therapies constitute a new and potentially valuable tool for GBM treatment, leading to the requirement of lower concentrations of chemotherapeutic drugs and possibly reducing, therefore, the adverse effects of chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Venenos de Cnidários/farmacologia , Dacarbazina/análogos & derivados , Etoposídeo/farmacologia , Glioblastoma/patologia , Animais , Western Blotting , Linhagem Celular Tumoral , Dacarbazina/farmacologia , Sinergismo Farmacológico , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Temozolomida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA