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1.
Qual Life Res ; 27(1): 267-271, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28677076

RESUMO

PURPOSE: The aim of this study was to translate and culturally adapt the Short Musculoskeletal Function Assessment (SMFA) into Danish (SMFA-DK) and assess the psychometric properties. METHODS: SMFA was translated and cross-culturally adapted according to a standardized procedure. Minor changes in the wording in three items were made to adapt to Danish conditions. Acute patients (n = 201) and rehabilitation patients (n = 231) with musculoskeletal problems aged 18-87 years were included. The following analysis were made to evaluate psychometric quality of SMFA-DK: Reliability with Chronbach's alpha, content validity as coding according to the International Classification of Functioning, Disability and Health (ICF), floor/ceiling effects, construct validity as factor analysis, correlations between SMFA-DK and Short Form 36 and also known group method. Responsiveness and effect size were calculated. RESULTS: Cronbach's alpha values were between 0.79 and 0.94. SMFA-DK captured all components of the ICF, and there were no floor/ceiling effects. Factor analysis demonstrated four subscales. SMFA-DK correlated good with the SF-36 subscales for the rehabilitation patients and lower for the newly injured patients. Effect sizes were excellent and better for SMFA-DK than for SF-36. CONCLUSION: The study indicates that SMFA-DK can be a valid and responsive measure of outcome in rehabilitation settings.


Assuntos
Comparação Transcultural , Avaliação da Deficiência , Doenças Musculoesqueléticas/diagnóstico , Psicometria/métodos , Qualidade de Vida/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/patologia , Reprodutibilidade dos Testes , Inquéritos e Questionários , Suécia
2.
Cell Mol Life Sci ; 74(24): 4561-4572, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28726057

RESUMO

Macrophage migration inhibitory factor (MIF), a small conserved protein, is abundant in the immune- and central nervous system (CNS). MIF has several receptors and binding partners that can modulate its action on a cellular level. It is upregulated in neurodegenerative diseases and cancer although its function is far from clear. Here, we report the finding of a new binding partner to MIF, the serine protease HTRA1. This enzyme cleaves several growth factors, extracellular matrix molecules and is implicated in some of the same diseases as MIF. We show that the function of the binding between MIF and HTRA1 is to inhibit the proteolytic activity of HTRA1, modulating the availability of molecules that can change cell growth and differentiation. MIF is therefore the first endogenous inhibitor ever found for HTRA1. It was found that both molecules were present in astrocytes and that the functional binding has the ability to modulate astrocytic activities important in development and disease of the CNS.


Assuntos
Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais/fisiologia , Animais , Astrócitos/metabolismo , Astrócitos/fisiologia , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células/fisiologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiologia , Células HEK293 , Serina Peptidase 1 de Requerimento de Alta Temperatura A , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica/fisiologia
3.
J Neurosci Res ; 93(2): 285-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25327365

RESUMO

The γ-aminobutyric acid (GABA) type B receptor has been implicated in glial cell development in the peripheral nervous system (PNS), although the exact function of GABA signaling is not known. To investigate GABA and its B receptor in PNS development and degeneration, we studied the expression of the GABAB receptor, GABA, and glutamic acid decarboxylase GAD65/67 in both development and injury in fetal dissociated dorsal root ganglia (DRG) cell cultures and in the rat sciatic nerve. We found that GABA, GAD65/67, and the GABAB receptor were expressed in premyelinating and nonmyelinating Schwann cells throughout development and after injury. A small population of myelinated sensory fibers displayed all of these molecules at the node of Ranvier, indicating a role in axon-glia communication. Functional studies using GABAB receptor agonists and antagonists were performed in fetal DRG primary cultures to study the function of this receptor during development. The results show that GABA, via its B receptor, is involved in the myelination process but not in Schwann cell proliferation. The data from adult nerves suggest additional roles in axon-glia communication after injury.


Assuntos
Bainha de Mielina/metabolismo , Nós Neurofibrosos/metabolismo , Receptores de GABA-B/metabolismo , Nervo Isquiático , Ácido gama-Aminobutírico/metabolismo , Animais , Animais Recém-Nascidos , Proliferação de Células/efeitos dos fármacos , Embrião de Mamíferos , GABAérgicos/farmacologia , Gânglios Espinais/citologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/metabolismo , Proteínas da Mielina/genética , Proteínas da Mielina/metabolismo , Glicoproteína Associada a Mielina/genética , Glicoproteína Associada a Mielina/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA-B/genética , Nervo Isquiático/citologia , Nervo Isquiático/embriologia , Nervo Isquiático/crescimento & desenvolvimento , Neuropatia Ciática/metabolismo , Neuropatia Ciática/patologia
4.
J Neurol Sci ; 457: 122888, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38278096

RESUMO

BACKGROUND: Predictive and prognostic biomarkers for multiple sclerosis (MS) remain a significant gap in MS diagnosis and treatment monitoring. Currently, there are no timely markers to diagnose the transition to secondary progressive MS (SPMS). OBJECTIVE: This study aims to evaluate the discriminatory potential of the High temperature requirement serine protease (HTRA1)/Macrophage migration inhibitory factor (MIF) cerebrospinal fluid (CSF) ratio in distinguishing relapsing-remitting (RRMS) patients from SPMS patients. METHODS: The MIF and HTRA1 CSF levels were determined using ELISA in healthy controls (n = 23), RRMS patients before (n = 22) and after 1 year of dimethyl fumarate treatment (n = 11), as well as in SPMS patients before (n = 11) and after 2 years of mitoxantrone treatment (n = 7). The ability of the HTRA1/MIF ratio to discriminate the different groups was determined using receiver operating curve (ROC) analyses. RESULTS: The ratio was significantly increased in treatment naïve RRMS patients while decreased again in SPMS patients at baseline. Systemic administrated disease modifying treatment (DMT) only significantly affected the ratio in RRMS patients. ROC analysis demonstrated that the ratio could discriminate treatment naïve RRMS patients from SPMS patients with 91% sensitivity and 100% specificity. CONCLUSION: The HTRA1/MIF ratio is a strong candidate as a MS biomarker for SPMS conversion.


Assuntos
Fatores Inibidores da Migração de Macrófagos , Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Esclerose Múltipla Crônica Progressiva/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Temperatura
5.
J Migr Health ; 8: 100200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37538300

RESUMO

Aims: The aim was to evaluate self-reported health status and wellbeing in a well-defined group of refugee families from Syria 2-4 years after resettlement in Denmark, and, where possible, compare it with a Danish reference population. The purpose was to determine the need for specialized health care to resettled refugees. Methods: This cross-sectional study involved 90 individuals from Syria aged 13-56 years. We used questionnaire survey to assess the general health and wellbeing in the study population in relation to a Danish reference population. Objective measurements of selected health indicators like overweight, hypertension and levels of cholesterol and blood glucose (HbA1c) were also determined for the study population. Results: Mean wellbeing scores and the proportion of study participants rating their health as good were lower among the study participants compared with the Danish population for all age groups. The proportion of participants who reported often being alone against their will was significantly higher than among Danes, as was the proportion who had nobody to talk to when having problems. A significantly higher proportion of participants experienced various forms of pain or discomfort than in the Danish population. Overall, 23.6% and 3.4% of participants had elevated cholesterol and HbA1c levels, respectively, and the prevalence of overweight (BMI ≥ 25) was 70%. Hypertension was more frequent (16.2%) than in another refugee population in Denmark (9%). Conclusions: The study demonstrated various mental and physical health challenges among the Syrian refugee families, and their health and wellbeing appeared to be substantially poorer as compared to the Danish reference population. The findings emphasize the need for systematic and specialized health care services at a municipality level to resettling refugees as a prerequisite for the refugees to become contributing citizens.

6.
J Neurol Sci ; 439: 120320, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35717879

RESUMO

BACKGROUND: Macrophage migration inhibitory factor (MIF) is involved in the function of both the innate and adaptive immune systems and in neuroprotection and has recently been implicated in multiple sclerosis (MS). OBJECTIVES: Determination of MIF levels in the cerebrospinal fluid (CSF) of patients with distinct subtypes of MS and the cellular localization of MIF in human brain tissue. METHODS: The levels of MIF were investigated in CSF from patients with clinically isolated syndrome (CIS) (n = 26), relapsing-remitting MS (RRMS) (n = 22), secondary progressive MS (SPMS) (n = 19), and healthy controls (HCs) (n = 24), using ELISA. The effect of disease-modifying therapies in the RRMS and SPMS cohorts were examined. Cellular distribution of MIF in the human brain was studied using immunochemistry and the newly available OligoInternode database. RESULTS: MIF was significantly decreased in treatment-naïve CIS and RRMS patients compared to HCs but was elevated in SPMS. Interestingly, MIF levels were sex-dependent and significantly lower in women with CIS and RRMS. MIF expression in the human brain was localized to neurons, astrocytes, pericytes, and oligo5 oligodendrocytes but not in microglia. CONCLUSION: The finding that MIF was decreased in newly diagnosed CIS and RRMS patients but was high in patients with SPMS may suggest that MIF levels in CSF are regulated by local MIF receptor expression that affects the overall MIF signaling in the brain and may represent a protective mechanism that eventually fails.


Assuntos
Fatores Inibidores da Migração de Macrófagos , Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Encéfalo , Feminino , Humanos , Oxirredutases Intramoleculares , Fatores Inibidores da Migração de Macrófagos/líquido cefalorraquidiano , Esclerose Múltipla Crônica Progressiva/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano
7.
Neurotherapeutics ; 18(2): 1257-1272, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33469829

RESUMO

Posttraumatic syringomyelia (PTS) is a serious condition of progressive expansion of spinal cord cysts, affecting patients with spinal cord injury years after injury. To evaluate neural cell therapy to prevent cyst expansion and potentially replace lost neurons, we developed a rat model of PTS. We combined contusive trauma with subarachnoid injections of blood, causing tethering of the spinal cord to the surrounding vertebrae, resulting in chronically expanding cysts. The cysts were usually located rostral to the injury, extracanalicular, lined by astrocytes. T2*-weighted magnetic resonance imaging (MRI) showed hyperintense fluid-filled cysts but also hypointense signals from debris and iron-laden macrophages/microglia. Two types of human neural stem/progenitor cells-fetal neural precursor cells (hNPCs) and neuroepithelial-like stem cells (hNESCs) derived from induced pluripotent stem cells-were transplanted to PTS cysts. Cells transplanted into cysts 10 weeks after injury survived at least 10 weeks, migrated into the surrounding parenchyma, but did not differentiate during this period. The cysts were partially obliterated by the cells, and cyst walls often merged with thin layers of cells in between. Cyst volume measurements with MRI showed that the volumes continued to expand in sham-transplanted rats by 102%, while the cyst expansion was effectively prevented by hNPCs and hNESCs transplantation, reducing the cyst volumes by 18.8% and 46.8%, respectively. The volume reductions far exceeded the volume of the added human cells. Thus, in an animal model closely mimicking the clinical situation, we provide proof-of-principle that transplantation of human neural stem/progenitor cells can be used as treatment for PTS.


Assuntos
Modelos Animais de Doenças , Células-Tronco Pluripotentes Induzidas/transplante , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco/métodos , Siringomielia/terapia , Vértebras Torácicas/lesões , Animais , Células Cultivadas , Células-Tronco Embrionárias/transplante , Feminino , Humanos , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia , Siringomielia/etiologia , Siringomielia/patologia
8.
J Neurol ; 268(9): 3316-3324, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33661357

RESUMO

BACKGROUND: High Temperature Requirement Serine Protease A1 (HTRA1) degrades extracellular matrix molecules (ECMs) and growth factors. It interacts with several proteins implicated in multiple sclerosis (MS), but has not previously been linked to the disease. OBJECTIVE: Investigate the levels of HTRA1 in cerebrospinal fluid (CSF) in different subtypes of MS and brain tissue. METHODS: Using ELISA, HTRA1 levels were compared in CSF from untreated patients with relapsing-remitting MS (RRMS, n = 23), secondary progressive MS (SPMS, n = 26) and healthy controls (HCs, n = 26). The effect of disease modifying therapies (DMTs) were examined in both patient groups. Cellular distribution in human brain was studied using immunochemistry and the oligointernode database, based on a single-nuclei RNA expression map. RESULTS: HTRA1 increased in RRMS and SPMS compared to HCs. DMT decreased HTRA1 levels in both types of MS. Using ROC analysis, HTRA1 cut-offs could discriminate HCs from RRMS patients with 100% specificity and 82.6% sensitivity. In the brain, HTRA1 was expressed in glia and neurons. CONCLUSION: HTRA1 is a promising CSF biomarker for MS correlating with disease- and disability progression. Most cell species of the normal and diseased CNS express HTRA1 and the expression pattern could reflect pathological processes involved in MS pathogenesis.


Assuntos
Serina Peptidase 1 de Requerimento de Alta Temperatura A/líquido cefalorraquidiano , Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Biomarcadores/química , Estudos de Casos e Controles , Progressão da Doença , Humanos , Esclerose Múltipla Crônica Progressiva/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano
9.
J Cell Mol Med ; 14(6B): 1816-23, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19538474

RESUMO

Recently, interest in the rat as an animal model of Alzheimer's disease (AD) has been growing. We have previously described the Tg6590 transgenic rat line expressing the amyloid precursor protein containing the Swedish AD mutation (K670M/N671L) that shows early stages of Abeta deposition, predominantly in cerebrovascular blood vessels, after 15 months of age. Here we show that by the age of 9 months, that is long before the appearance of Abeta deposits, the Tg6590 rats exhibit deficits in the Morris water maze spatial navigation task and altered spontaneous behaviour in the open-field test. The levels of soluble Abeta were elevated both in the hippocampus and cortex of transgenic animals. Magnetic resonance imaging showed no major changes in the brains of transgenic animals, although they tended to have enlarged lateral ventricles when compared to control animals. The Tg6590 transgenic rat line should prove a suitable model of early AD for advanced studies including serial cerebrospinal fluid sampling, electrophysiology, neuroimaging or complex behavioural testing.


Assuntos
Doença de Alzheimer/complicações , Precursor de Proteína beta-Amiloide/metabolismo , Transtornos Cognitivos/complicações , Modelos Animais de Doenças , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Comportamento Animal , Biomarcadores/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Transtornos Cognitivos/fisiopatologia , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Aprendizagem em Labirinto , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Ratos , Ratos Transgênicos , Sinapses/metabolismo , Sinapses/patologia , Proteínas tau/metabolismo
10.
Front Immunol ; 11: 1110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582192

RESUMO

Background: MiR-146a is an important regulator of innate inflammatory responses and is also implicated in cell death and survival. Methods: By sorting CNS resident cells, microglia were the main cellular source of miR-146a. Therefore, we investigated microglia function and phenotype in miR-146a knock-out (KO) mice, analyzed the proteome of KO and wild-type (WT) microglia by LC-MS/MS, and examined miR-146a expression in different brain lesions of patients with multiple sclerosis (MS). Results: When stimulated with LPS or myelin in vitro, microglia from KO mice expressed higher levels of IL-1ß, TNF, IL-6, IL-10, CCL3, and CCL2 compared to WT. Stimulation increased migration and phagocytosis of WT but not KO microglia. CD11c+ microglia were induced by cuprizone (CPZ) in the WT mice but less in the KO. The proteome of ex vivo microglia was not different in miR-146a KO compared to WT mice, but CPZ treatment induced differential and reduced protein responses in the KO: GOT1, COX5b, CRYL1, and cystatin-C were specifically changed in KO microglia. We explored discriminative features of microglia proteomes: sparse Partial Least Squares-Discriminant Analysis showed the best discrimination when control and CPZ-treated conditions were compared. Cluster of ten proteins separated WT and miR-146a KO microglia after CPZ: among them were sensomes allowing to perceive the environment, Atp1a3 that belongs to the signature of CD11c+ microglia, and proteins related to inflammatory responses (S100A9, Ppm1g). Finally, we examined the expression of miR-146a and its validated target genes in different brain lesions of MS patients. MiR-146 was upregulated in all lesion types, and the highest expression was in active lesions. Nineteen of 88 validated target genes were significantly changed in active lesions, while none were changed in NAWM. Conclusion: Our data indicated that microglia is the major source of miR-146a in the CNS. The absence of miR-146a differentially affected microglia function and proteome, and miR-146a may play an important role in gene regulation of active MS lesions.


Assuntos
MicroRNAs/metabolismo , Microglia/metabolismo , Esclerose Múltipla/metabolismo , Animais , Quelantes/toxicidade , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/imunologia , Microglia/imunologia , Esclerose Múltipla/imunologia , Proteoma
11.
J Cell Mol Med ; 13(6): 1034-42, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19432812

RESUMO

As a disease model, the laboratory rat has contributed enormously to neuroscience research over the years. It has also been a popular animal model for Alzheimer's disease but its popularity has diminished during the last decade, as techniques for genetic manipulation in rats have lagged behind that of mice. In recent years, the rat has been making a comeback as an Alzheimer's disease model and the appearance of increasing numbers of transgenic rats will be a welcome and valuable complement to the existing mouse models. This review summarizes the contributions and current status of the rat as an animal model of Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Modelos Animais de Doenças , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Animais Geneticamente Modificados , Humanos , Ratos
12.
Neurosci Lett ; 444(3): 275-9, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18761056

RESUMO

Altered calcium homeostasis is implicated in the pathogenesis of Alzheimer's disease and much effort has been put into understanding the association between the autosomal dominant gene mutations causative of this devastating disease and perturbed calcium signaling. We have focused our attention on the effect of the APP670/671 mutation on spontaneous calcium oscillations in embryonic hippocampal neurons derived from the tg6590 transgenic rat. Intracellular free calcium levels were imaged by confocal microscopy using the fluorescent dye fluo-3AM. Hyperosmotic shrinkage, which can occur in a variety of pathophysiological conditions, has been shown to induce multiple cellular responses, including activation of volume-regulatory ion transport, cytoskeletal reorganization, and cell death. When exposed to hyperosmotic stress (addition of 50mM sucrose) the frequency of calcium oscillations was suppressed to an equal extent in both wild-type and transgenic cultures, but the transgenic neurons, in contrast to the wild-type neurons, responded with a significantly higher increase in the amplitude of oscillations. A decrease in cell viability was observed by means of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay in neurons exposed to the hyperosmotic medium for 30h. Whereas this loss in cell viability was comparable in both sets of cultures, the amplitude of calcium oscillations in transgenic neurons exhibited a significantly greater decrease in the presence of the L-type calcium channel antagonist, nimodipine. These results suggest that APP670/671 transgenic neurons have impaired calcium homeostasis.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Sinalização do Cálcio , Hipocampo/citologia , Neurônios/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo L/fisiologia , Sobrevivência Celular , Células Cultivadas , Embrião de Mamíferos/citologia , Mutação , Neurônios/citologia , Osmose , Ratos , Ratos Transgênicos , Sacarose/farmacologia
13.
Neurosci Lett ; 436(2): 250-4, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18403114

RESUMO

Altered calcium homeostasis is implicated in the pathogenesis of Alzheimer's disease (AD). Much effort has been put into understanding the association between protein mutations causative of this devastating neurodegenerative disease and perturbed calcium signaling. Whereas the presenilin mutations have received most attention in the context of neuronal calcium signaling, we focused on the effects of APP with the so-called Swedish mutation (APPswe) on spontaneous neuronal activity. We observed that primary hippocampal neurons from an APPswe transgenic rat showed increased frequency and unaltered amplitude of spontaneous calcium oscillations as compared to wild-type neurons. We found that the altered calcium signaling of APPswe transgenic neurons was unlikely to be due to modulation of the NMDA or nicotinic neurotransmitter systems, and did not depend on secreted APP derivates. The implications of this effect of APP are discussed.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Sinalização do Cálcio/fisiologia , Hipocampo/citologia , Mutação/fisiologia , Neurônios/metabolismo , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Bungarotoxinas/farmacologia , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos , Agonistas de Aminoácidos Excitatórios/farmacologia , Humanos , N-Metilaspartato/farmacologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
Front Immunol ; 9: 490, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29593734

RESUMO

Background: The cuprizone (CPZ) model of multiple sclerosis (MS) was used to identify microRNAs (miRNAs) related to in vivo de- and remyelination. We further investigated the role of miR-146a in miR-146a-deficient (KO) mice: this miRNA is differentially expressed in MS lesions and promotes differentiation of oligodendrocyte precursor cells (OPCs) during remyelination, but its role has not been examined during demyelination. Methods: MicroRNAs were examined by Agilent Mouse miRNA Microarray in the corpus callosum during CPZ-induced demyelination and remyelination. Demyelination, axonal loss, changes in number of oligodendrocytes, OPCs, and macrophages/microglia was compared by histology/immunohistochemistry between KO and WT mice. Differential expression of target genes and proteins of miR-146a was analyzed in the transcriptome (4 × 44K Agilent Whole Mouse Genome Microarray) and proteome (liquid chromatography tandem mass spectrometry) of CPZ-induced de- and remyelination in WT mice. Levels of proinflammatory molecules in the corpus callosum were compared in WT versus KO mice by Meso Scale Discovery multiplex protein analysis. Results: miR-146a was increasingly upregulated during CPZ-induced de- and remyelination. The absence of miR-146a in KO mice protected against demyelination, axonal loss, body weight loss, and atrophy of thymus and spleen. The number of CNP+ oligodendrocytes was increased during demyelination in the miR-146a KO mice, while there was a trend of increased number of NG2+ OPCs in the WT mice. miR-146a target genes, SNAP25 and SMAD4, were downregulated in the proteome of demyelinating corpus callosum in WT mice. Higher levels of SNAP25 were measured by ELISA in the corpus callosum of miR-146a KO mice, but there was no difference between KO and WT mice during demyelination. Multiplex protein analysis of the corpus callosum lysate revealed upregulated TNF-RI, TNF-RII, and CCL2 in the WT mice in contrast to KO mice. The number of Mac3+ and Iba1+ macrophages/microglia was reduced in the demyelinating corpus callosum of the KO mice. Conclusion: During demyelination, absence of miR-146a reduced inflammatory responses, demyelination, axonal loss, the number of infiltrating macrophages, and increased the number of myelinating oligodendrocytes. The number of OPCs was slightly higher in the WT mice during remyelination, indicating a complex role of miR-146a during in vivo de- and remyelination.


Assuntos
Axônios/patologia , Corpo Caloso/fisiologia , Doenças Desmielinizantes/genética , MicroRNAs/genética , Oligodendroglia/fisiologia , Animais , Diferenciação Celular , Quimiocina CCL2/genética , Cuprizona , Feminino , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Receptores do Fator de Necrose Tumoral/genética
15.
Brain Res ; 1186: 102-12, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17997397

RESUMO

NR3A, representing the third class of NMDA receptor subunits, was first studied in rats, demonstrating ubiquitous expression in the developing central nervous system (CNS), but in the adult mainly expressed in spinal cord and some forebrain nuclei. Subsequent studies showed that rodent and non-human primate NR3A expression differs. We have studied the distribution of NR3A in the human CNS and show a widespread distribution of NR3A protein in adult human brain. NR3A mRNA and protein were found in all regions of the cerebral cortex, and also in the subcortical forebrain, midbrain and hindbrain. Only very low levels of NR3A mRNA and protein could be detected in homogenized adult human spinal cord, and in situ hybridization showed that expression was limited to ventral motoneurons. We found that NR3A is associated with NR1, NR2A and NR2B in adult human CNS, suggesting the existence of native NR1-NR2A/B-NR3A assemblies in adult human CNS. While NR1 and NR2A could only be efficiently solubilized by deoxycholate, NR3A was extracted by all detergents, suggesting that a large fraction is weakly anchored to cell membranes and other proteins. Using size exclusion chromatography we found that just as for NR1, a large fraction of NR3A exists as monomers and dimers, suggesting that these two glycine binding subunits behave similarly with regard to receptor assembly and trafficking.


Assuntos
Encéfalo/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Medula Espinal/metabolismo , Animais , Feminino , Humanos , Imuno-Histoquímica , Macaca , Conformação Proteica , Subunidades Proteicas/classificação , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/genética , Distribuição Tecidual
16.
Physiol Behav ; 92(1-2): 54-9, 2007 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-17617428

RESUMO

In the present paper we describe our on-going project investigating the functional roles of the N-methyl-D-aspartate (NMDA) receptor subunit NR3A. We find that NR3A mRNA is abundant both in embryonic and adult human brain, in contrast to the almost non-existing expression in adult rodent brain. Human NR3A (hNR3A) protein expression is particularly abundant in the cerebral cortex, as shown by western blot using NR3A-specific antibodies. Distribution of hNR3A in adult human brain shows a similar pattern as NR3A in post-natal rodent brain. We have previously reported that NR3A contains a glycine binding site, with similar affinity as the glycine binding site of NR1 subunits. This suggests that NR3A may replace one of the two NR1 subunits in native NMDA receptors. Cloning of hNR3A showed a human-specific polyproline-sequence in the intracellular C-terminus, that may bind to SH3-domains. We hypothesized that the significant differences in expression in the adult human and rodent brain could be due to an atypical interaction of hNR3A with the SH3 domain of the synaptic scaffolding protein PSD-95, that binds to NR2 subunits through its PDZ domains. However, using a number of different protein interaction assays, binding of PSD-95 to hNR3A could no be demonstrated either in vitro or in vivo. To identify intracellular signaling pathways for NR3A-containing NMDA receptors, we screened for proteins interacting with hNR3A and identified three proteins: plectin, CARP-1 and GPS2. The possible physiological roles of these interactions are discussed.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Sinapses/fisiologia , Animais , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Espinhas Dendríticas/fisiologia , Humanos , Camundongos , Subunidades Proteicas , Ratos , Receptores de N-Metil-D-Aspartato/genética
17.
Stem Cells Dev ; 26(12): 876-887, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28351210

RESUMO

Nonpluripotent neural progenitor cells (NPCs) derived from the human fetal central nervous system were found to express a number of messenger RNA (mRNA) species associated with pluripotency, such as NANOG, REX1, and OCT4. The expression was restricted to small subpopulations of NPCs. In contrast to pluripotent stem cells, there was no coexpression of the pluripotency-associated genes studied. Although the expression of these genes rapidly declined during the in vitro differentiation of NPCs, we found no evidence that the discrete expression was associated with the markers of multipotent neural stem cells (CD133+/CD24lo), the capacity of sphere formation, or high cell proliferation rates. The rate of cell death among NPCs expressing pluripotency-associated genes was also similar to that of other NPCs. Live cell imaging showed that NANOG- and REX1-expressing NPCs continuously changed morphology, as did the nonexpressing cells. Depletion experiments showed that after the complete removal of the subpopulations of NANOG- and REX1-expressing NPCs, the expression of these genes appeared in other NPCs within a few days. The percentage of NANOG- and REX1-expressing cells returned to that observed before depletion. Our results are best explained by a model in which there is stochastic transient expression of pluripotency-associated genes in proliferating NPCs.


Assuntos
Antígenos de Diferenciação/biossíntese , Regulação da Expressão Gênica/fisiologia , Células-Tronco Neurais/metabolismo , Células-Tronco Pluripotentes/metabolismo , Humanos , Células-Tronco Neurais/citologia , Células-Tronco Pluripotentes/citologia
18.
FEBS Lett ; 580(1): 107-14, 2006 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-16364302

RESUMO

Currently, we found that the 70-kDa p70 S6 kinase (p70S6K) directly phosphorylates tau at S262, S214, and T212 sites in vitro. By immunoprecipitation, p-p70S6K (T421/S424) showed a close association with p-tau (S262 and S396/404). Zinc-induced p70S6K activation could only upregulate translation of total S6 and tau but not global proteins in SH-SY5Y cells. The requirement of p70S6K activation was confirmed in the SH-SY5Y cells that overexpress wild-type htau40. Level of p-p70S6K (T421/S424) was only significantly correlated with p-tau at S262, S214, and T212, but not T212/S214, in Alzheimer's disease (AD) brains. These suggested that p70S6K might contribute to tau related pathologies in AD brains.


Assuntos
Proteínas de Membrana/metabolismo , Biossíntese de Proteínas/fisiologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Linhagem Celular Tumoral , Sistema Livre de Células/química , Sistema Livre de Células/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Proteínas de Membrana/química , Fosforilação/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 70-kDa/química , Serina/química , Serina/metabolismo , Treonina/química , Treonina/metabolismo , Zinco/química , Zinco/farmacologia
19.
Toxicol Lett ; 161(2): 152-8, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-16174552

RESUMO

Polychlorinated Biphenyls (PCBs)-induced changes in synaptic transmission are one of the effects of their neurotoxicity but the mechanism remains unknown. We assessed the in vivo effects of the PCBs mixture, Aroclor 1254 on the expression of neuronal proteins that are involved in the synaptic function and/or are associated with neurodegeneration. Wistar rats were treated orally with repeated doses of Aroclor 1254 and the levels of soluble alpha-synuclein, parkin, synaptophysin and amyloid precursor protein (APP) in the brain were determined by Western blotting. The results showed that Aroclor did not cause changes in the expression and processing of APP but at a dose 100 microg/g/day repeated for 6 days caused a decrease in the expression of alpha-synuclein in the cerebellum, cortex, hippocampus and hypothalamus of the animals sacrificed 2 days after treatment. The decrease in alpha-synuclein was accompanied by a transient increase in parkin and synaptophysin levels. Interestingly, in the hypothalamus the levels of alpha-synuclein remained decreased after 21 days post treatment perhaps due to regional differences in the PCBs elimination or perhaps a more specific interaction with the dopaminergic cells that are present in the hypothalamus that needs to be investigated further.


Assuntos
Encéfalo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Sinaptofisina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , alfa-Sinucleína/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Wistar
20.
Environ Toxicol Pharmacol ; 21(1): 51-5, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21783638

RESUMO

Pyrethroids, widely used insecticides, are biologically active in neurons. Whether they act on the non-neuronal brain cells remains an open question. Thus, the aim of this study was to examine whether Cypermethrin intoxication affects astroglial cells in the rat brain. The levels of Glial Fibrillary Acidic Protein (GFAP) in different brain regions were measured by ELISA following oral treatment with 5 or 10% of LD(50) of Cypermethrin per day for 6 days. A significant decrease of GFAP was observed in different brain regions of treated animals. The cerebral cortex showed the most pronounced effect with GFAP levels reduced to 81% of the controls 2 days after treatment and 77% 21 days after treatment. Although we did not find profound changes in the morphology of astrocytes in Cypermethrin treated animals, the decrease in GFAP suggests that astrocytes were affected by low doses of pyrethroids. The possible consequences were discussed.

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