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1.
Eur J Neurol ; 15(9): 893-908, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18796075

RESUMO

Despite high-dose intravenous immunoglobulin (IVIG) is widely used in treatment of a number of immune-mediated neurological diseases, the consensus on its optimal use is insufficient. To define the evidence-based optimal use of IVIG in neurology, the recent papers of high relevance were reviewed and consensus recommendations are given according to EFNS guidance regulations. The efficacy of IVIG has been proven in Guillain-Barré syndrome (level A), chronic inflammatory demyelinating polyradiculoneuropathy (level A), multifocal mononeuropathy (level A), acute exacerbations of myasthenia gravis (MG) and short-term treatment of severe MG (level A recommendation), and some paraneoplastic neuropathies (level B). IVIG is recommended as a second-line treatment in combination with prednisone in dermatomyositis (level B) and treatment option in polymyositis (level C). IVIG should be considered as a second or third-line therapy in relapsing-remitting multiple sclerosis, if conventional immunomodulatory therapies are not tolerated (level B), and in relapses during pregnancy or post-partum period (good clinical practice point). IVIG seems to have a favourable effect also in paraneoplastic neurological diseases (good practice point) [corrected],stiff-person syndrome (level A), some acute-demyelinating diseases and childhood refractory epilepsy (good practice point).


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Doenças do Sistema Nervoso/terapia , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Autoimunes do Sistema Nervoso/terapia , Ensaios Clínicos como Assunto , Terapia Combinada , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/terapia , Epilepsia/terapia , Medicina Baseada em Evidências , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/efeitos adversos , Imunoglobulinas Intravenosas/farmacologia , Imunossupressores/uso terapêutico , Polineuropatia Paraneoplásica/imunologia , Polineuropatia Paraneoplásica/terapia , Paraproteinemias/imunologia , Paraproteinemias/terapia , Troca Plasmática
2.
Acta Neurol Scand ; 116(4): 226-30, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17824899

RESUMO

OBJECTIVES: Experimental studies suggest increased cerebral production of inflammatory cytokines after prolonged seizures. Whether a single non-prolonged seizure in human patients is associated with activation of cytokine network is still unknown. MATERIALS AND METHODS: We studied the levels of interleukin-1beta (IL-1beta), interleukin-1 receptor antagonist (IL-1ra), interlukin-6 (IL-6) and soluble IL-6 receptors (sIL-6R and Gp130) in plasma after single seizures during video-EEG recordings in patients with chronic localization-related epilepsy. RESULTS: The levels of IL-1ra and IL-6 were increased after seizures, whereas IL-1beta and IL-6 cytokine receptors remained unchanged. CONCLUSIONS: These results show that only single seizures cause activation of cytokine cascade and associated inflammatory signals. In the case of recurrent seizures, these signals may result in structural changes in the nervous tissue, which are generally associated with drug refractory epilepsy.


Assuntos
Epilepsias Parciais/sangue , Proteína Antagonista do Receptor de Interleucina 1/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Receptores de Interleucina-6/sangue , Adulto , Eletroencefalografia , Epilepsias Parciais/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Gravação em Vídeo
3.
Brain Res Mol Brain Res ; 137(1-2): 272-5, 2005 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-15950787

RESUMO

ADAM metalloprotease-disintegrins mediate cell adhesion, proteolytic processing, and signal transduction. In the present study, the mRNA levels of ADAM9, ADAM10, and ADAM15 were examined in rat brain after kainic acid (KA)-induced status epilepticus. ADAM9 and ADAM10 expression was induced in dentate gyrus of hippocampus. ADAM15 expression remained unchanged. The spatiotemporal expression of ADAM9 and ADAM10 suggests that their regulation after the KA-induced status epilepticus could be related to neuroprotection.


Assuntos
Ácido Aspártico Endopeptidases/genética , Giro Denteado/metabolismo , Desintegrinas/genética , Epilepsia/metabolismo , Proteínas de Membrana/genética , Metaloendopeptidases/genética , Metaloproteases/genética , Estado Epiléptico/metabolismo , Proteínas ADAM , Secretases da Proteína Precursora do Amiloide , Animais , Convulsivantes , Giro Denteado/fisiopatologia , Modelos Animais de Doenças , Endopeptidases , Epilepsia/induzido quimicamente , Epilepsia/fisiopatologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Ácido Caínico , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/fisiopatologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
4.
J Neuroimmunol ; 152(1-2): 121-5, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15223244

RESUMO

Experimental studies suggest that cytokine production may be triggered by seizure activity. Here we determined the levels of interleukin-6 (IL-6) and its soluble receptor components (sIL-6R and sGp130) in CSF and serum from control subjects and patients after different types of seizures. IL-6 levels were increased after seizures, whereas sIL-6R levels were decreased. Interestingly, the levels of IL-6 were strongly increased after recurrent generalized tonic-clonic seizures (GTCS), whereas after single tonic-clonic or prolonged partial seizures IL-6 levels were increased to lesser extent. These results provide further support for a hypothesis of cytokine production induced by seizure activity per se.


Assuntos
Interleucina-6/sangue , Interleucina-6/líquido cefalorraquidiano , Convulsões/imunologia , Convulsões/fisiopatologia , Antígenos CD/sangue , Antígenos CD/líquido cefalorraquidiano , Receptor gp130 de Citocina , Ensaio de Imunoadsorção Enzimática , Humanos , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/líquido cefalorraquidiano , Receptores de Interleucina-6/análise
5.
Brain Res Mol Brain Res ; 110(2): 253-60, 2003 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-12591161

RESUMO

We have previously shown that IL-6 protein levels are increased in cerebrospinal fluid in humans after recent tonic-clonic seizures with unchanged levels of IL-1beta and TNFalpha. Here we studied the expression of cytokines IL-6, LIF, IL-1beta and TNFalpha and cytokine receptors IL-6R, LIFR and Gp130 in the rat brain after kainic acid-induced status epilepticus using Northern blot analysis and in situ hybridization histochemistry. After seizures, IL-6 mRNA was induced in the hippocampus, cortex, amygdala and meninges, and IL-6R was up-regulated in the hippocampus. LIF was up-regulated in the hippocampus, cortex and meninges after seizures, and LIFR mRNA was induced in the hippocampus and cortex. Gp130 was constitutively expressed in the brain. After seizures, Gp130 transcription was rapidly induced in the meninges. In thalamus, cortex, amygdala and hippocampus Gp130 mRNA was induced in a delayed fashion. IL-1beta transcription was induced in the temporal lobe cortex and thalamus, and TNFalpha in the hippocampus. In general, the cytokine and their receptor mRNA levels were low in intact rat brain, but were induced by seizures. Since IL-6 and LIF transcripts were induced in the meninges after seizures, the protein products of these transcripts may be more readily released in cerebrospinal fluid after seizures. In addition, the activity of IL-6 and LIF signaling pathways may be influenced by increased expression of their receptors after seizures.


Assuntos
Encéfalo/metabolismo , Citocinas/genética , Epilepsia/metabolismo , Neurônios/metabolismo , Receptores de Citocinas/genética , Animais , Encéfalo/fisiopatologia , Contactinas , Epilepsia/induzido quimicamente , Epilepsia/genética , Regulação da Expressão Gênica/fisiologia , Inibidores do Crescimento/genética , Interleucina-1/genética , Interleucina-6/genética , Fator Inibidor de Leucemia , Subunidade alfa de Receptor de Fator Inibidor de Leucemia , Linfocinas/genética , Masculino , Moléculas de Adesão de Célula Nervosa/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Interleucina-6/genética , Receptores de OSM-LIF , Fator de Necrose Tumoral alfa/genética
6.
AJNR Am J Neuroradiol ; 22(6): 1117-24, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11415907

RESUMO

BACKGROUND AND PURPOSE: White matter lesions on MR images obtained from patients with acute disseminated encephalomyelitis (ADEM) have been reported to appear shortly after symptom onset, and their resolution has been claimed to parallel recovery. To elucidate the temporal evolution of these lesions and to associate the changes on MR images to the patients' clinical condition, we performed serial MR imaging on patients with ADEM. METHODS: Several consecutive T2-weighted and fluid-attenuated inversion recovery scans were obtained from four previously healthy adult patients with ADEM within the first days after the onset of symptoms and again during the recovery period. MR imaging was done first on a weekly to biweekly basis and later at 1- to 2-month intervals for up to 8 months. RESULTS: MR scans of three of these patients did not show any specific abnormalities until several weeks after the onset of the disease. As the lesions later appeared, their number increased during the recovery period. CONCLUSION: MR imaging performed during the first days after the onset of the disease may not reveal any pathologic findings. The appearance of the ADEM-associated MR imaging changes may be associated with recovery rather than decline. It remains to be studied whether the new MR imaging techniques reveal the lesions associated with ADEM faster than the conventional T2-weighted imaging.


Assuntos
Encefalomielite Aguda Disseminada/diagnóstico , Aumento da Imagem , Imageamento por Ressonância Magnética , Adulto , Encéfalo/patologia , Diagnóstico Diferencial , Encefalomielite Aguda Disseminada/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico
7.
Curr Protoc Toxicol ; Appendix 3: A.3E.1-.13, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-20972965

RESUMO

This unit describes the processes of extracting RNA from tissues and analyzing it by northern blot hybridization to probe the expression of a particular gene at the transcriptional level.


Assuntos
Northern Blotting/métodos , RNA/análise , RNA/química , RNA Mensageiro/análise , RNA Mensageiro/química , Toxicologia/métodos
8.
Brain Res ; 877(2): 203-8, 2000 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-10986333

RESUMO

The secretion of steroid hormones from the adrenal cortex as well as cathecolamines from the adrenal medulla is stimulated by stress. In this study, we studied the effect of capsaicin-induced stress on the expression of the immediate-early genes (IEGs) NGFI-A, -B, -C, egr-2, -3 and Nurr1 in the rat adrenal gland using in situ hybridization. All of these IEGs except egr-2 were rapidly induced in the adrenal cortex and medulla. The temporal patterns of the IEG induction in medulla varied significantly. NGFI-A was induced in medulla within 15 min after stress, NGFI-B, egr-3 and Nurr1 were induced by 30 min, whereas NGFI-C was induced by 2 h. Surprisingly, only NGFI-B and Nurr1 were induced in the glucocorticoid secreting regions of zonae reticularis and fasciculata of the cortex, starting 15 min after the stress. All of the inducible IEGs were induced in the aldosterone secreting zona glomerulosa 15-30 min after the capsaicin injection. NGFI-A, NGFI-B and Nurr1 expression persisted for 6 h. Since the IEGs studied had major differences in their temporospatial induction pattern, they are likely to be induced by distinct stress-elicited factors and have separate target genes and roles in stress-induced glucocorticoid and catecholamine secretion.


Assuntos
Glândulas Suprarrenais/metabolismo , Genes Precoces/fisiologia , Proteínas Imediatamente Precoces , Estresse Fisiológico/metabolismo , Dedos de Zinco/genética , Córtex Suprarrenal/citologia , Córtex Suprarrenal/metabolismo , Glândulas Suprarrenais/citologia , Medula Suprarrenal/citologia , Medula Suprarrenal/metabolismo , Animais , Capsaicina/farmacologia , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce , Proteína 2 de Resposta de Crescimento Precoce , Proteína 3 de Resposta de Crescimento Precoce , Masculino , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares , Receptores de Esteroides , Estresse Fisiológico/induzido quimicamente , Fatores de Tempo , Fatores de Transcrição/genética
9.
Neuroradiology ; 42(12): 895-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11198208

RESUMO

We describe a young woman with Burkitt's lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Síndromes Neurotóxicas/patologia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Injeções Espinhais , Leucócitos , Imageamento por Ressonância Magnética , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/etiologia , Esteroides/uso terapêutico
11.
Eur J Neurosci ; 11(1): 10-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9987007

RESUMO

In the present study in situ hybridization was used to study the effect of kainic acid induced seizures on the expression of the zinc finger immediate-early genes (IEGs) NGFI-A, NGFI-B, NGFI-C, egr-2; egr-3 and Nurr1. Kainic acid markedly induced these IEGs especially in hippocampus, cortex and amygdala by 30 min. This induction gradually decreased and returned to baseline by 24 h in most regions. However, in the CA1 and CA3 subfields of hippocampus known to be damaged by kainic acid the expression of all the IEGs except egr-2 remained elevated for 24 h. NGFI-A, NGFI-B, NGFI-C and to a lesser extent, Nurr1, remained elevated also in the subcortical region of the temporal lobe. By 24 h incorporation of 14C-leucine decreased in the piriform cortex, amygdala, and in the CA1 and CA3 subfields, but not in CA2 and dentate gyrus. These areas showing decreased protein synthesis in the hippocampus by 24 h showed prolonged IEG induction, whereas IEG expression returned to control levels in areas showing normal protein synthesis. In the temporal lobe decreased protein synthesis coexisted with decreased IEG expression, whereas areas in the vicinity of the region showing decreased protein synthesis demonstrated elevated IEG expression. The decreased protein synthesis was localized in areas where extensive neuronal death has occurred. This prolonged IEG induction in the hippocampus, which has been linked with neuronal death, could solely represent a prolonged mRNA turnover caused by disrupted protein synthesis. The prolonged IEG expression in the temporal lobe appeared to be localized in regions where the cells are in stress, but still viable. The sustained IEG expression might therefore either represent a stress response by which the neurons are trying to protect themselves or, alternatively, the IEG response may be an early sign indicating that these cells are initiating a pathway leading to programmed cell death.


Assuntos
Epilepsia/fisiopatologia , Genes Precoces/genética , Proteínas Imediatamente Precoces , Dedos de Zinco/genética , Tonsila do Cerebelo/química , Tonsila do Cerebelo/citologia , Animais , Córtex Cerebral/química , Córtex Cerebral/citologia , Proteínas de Ligação a DNA/genética , Giro Denteado/química , Giro Denteado/citologia , Proteína 1 de Resposta de Crescimento Precoce , Proteína 2 de Resposta de Crescimento Precoce , Proteína 3 de Resposta de Crescimento Precoce , Epilepsia/induzido quimicamente , Agonistas de Aminoácidos Excitatórios , Regulação da Expressão Gênica/fisiologia , Ácido Glutâmico/metabolismo , Hibridização In Situ , Ácido Caínico , Masculino , Proteínas do Tecido Nervoso/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Sondas de Oligonucleotídeos , Células Piramidais/química , Células Piramidais/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares , Receptores de Esteroides , Fatores de Transcrição/genética
12.
Brain Res ; 808(1): 56-64, 1998 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-9795133

RESUMO

The mitochondrial toxin, 3-nitropropionic acid (3-NP), is an irreversible inhibitor of succinate dehydrogenase that induces apoptosis in vitro and in vivo. We injected 3-NP into the striatum of rats to examine the potential role of Bcl-2 or Bcl-x, proteins that can inhibit apoptosis, in brain injury due to 3-NP. Electrophoretic examination of striatal tissue indicated that 3-NP induced internucleosomal fragmentation typical of apoptosis. There was also histologic evidence of apoptosis based on staining by the terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) method. Apoptosis was first observed 6 h after injection, was maximal at 1 day, and was still observed on day 7. Expression of bcl-2, bcl-x, and c-jun mRNA expression was evaluated 1, 3, 6, and 12 h and 1, 3, 5, and 7 days after injection using in situ hybridization. Both bcl-2 and bcl-x mRNA expression in the striatum decreased starting at 6 h and continued to 5 days after injection. This was in contrast to an apparent increase in c-jun expression. The similarity in the time course of apoptosis to that of suppression of bcl-2 and bcl-x mRNA suggests that changes in expression of these genes may contribute to apoptosis following 3-NP injection.


Assuntos
Apoptose/fisiologia , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Propionatos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Lateralidade Funcional , Genes bcl-2 , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Masculino , Nitrocompostos , Propionatos/administração & dosagem , Proteínas Proto-Oncogênicas c-jun/genética , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Succinato Desidrogenase/antagonistas & inibidores , Proteína bcl-X
13.
Brain Res Mol Brain Res ; 60(1): 1-12, 1998 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-9748473

RESUMO

Examination of null-mutant Drosophila and Leukocyte Common Antigen-Related (LAR)-deficient transgenic mice has demonstrated that the LAR protein tyrosine phosphatase (PTP) receptor promotes neurite outgrowth. In the absence of known ligands, the mechanisms by which LAR-type PTP receptors are regulated are unknown. We hypothesized that an alternatively spliced eleven amino acid proximal membrane segment of LAR (LAR alternatively spliced element-a; LASE-a) contributes to regulation of LAR function. Human, rat and mouse LAR cDNA sequences demonstrated that the predicted eleven amino acid inserts in rat and mouse are identical and share nine of eleven residues with the human insert. LASE-a splicing led to the introduction of a Ser residue into LAR at a position analogous to Ser residues undergoing regulated phosphorylation in other PTPs. In-situ studies revealed increasingly region-specific expression of LASE-a containing LAR transcripts during postnatal development. RT-PCR analysis of cortical and hippocampal tissue confirmed that the proportion of LAR transcripts containing LASE-a decreases during development. Immunostaining of cultured PC12 cells, cerebellar granule neurons, dorsal root ganglia and sciatic nerve sections with antibody directed against the LASE-a insert demonstrated signal in cell bodies but little if any along neurites. In contrast, staining with antibody directed to a separate domain of LAR showed accumulation of LAR along neurites. The findings that LASE-a splicing is conserved across human, rat and mouse, that the LASE-a insert introduces a Ser at a site likely to be targeted for regulated phosphorylation and that developmentally regulated splicing is coordinated with specific regional and intraneuronal localization point to important novel potential mechanisms regulating LAR-type tyrosine phosphatase receptor function in the nervous system.


Assuntos
Processamento Alternativo/fisiologia , Proteínas do Tecido Nervoso , Neurônios/enzimologia , Neurônios/fisiologia , Proteínas Tirosina Fosfatases , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Animais , Anticorpos , Cerebelo/química , Cerebelo/citologia , Cerebelo/enzimologia , Córtex Cerebral/química , Córtex Cerebral/citologia , Córtex Cerebral/enzimologia , Pré-Escolar , Clonagem Molecular , DNA Complementar , Feminino , Gânglios Espinais/química , Gânglios Espinais/citologia , Gânglios Espinais/enzimologia , Expressão Gênica , Biblioteca Gênica , Hipocampo/química , Humanos , Camundongos , Dados de Sequência Molecular , Neurônios/química , Células PC12 , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores , Receptores de Superfície Celular/análise , Receptores de Superfície Celular/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nervo Isquiático/química , Nervo Isquiático/citologia , Nervo Isquiático/enzimologia , Medula Espinal/química , Medula Espinal/citologia , Medula Espinal/enzimologia , Transcrição Gênica/fisiologia
14.
Mol Cell Neurosci ; 10(5/6): 271-86, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9618218

RESUMO

Transgenic mice and Drosophila mutant studies demonstrate that the leukocyte common antigen-related (LAR) protein tyrosine phosphatase (PTPase) receptor is required for formation of neural networks. We assessed the hypothesis that alternative splicing of the LAR extracellular region contributes to this function by establishing temporospatial expression patterns of LAR isoforms containing an alternatively spliced extracellular nine amino acid segment (LAR alternatively spliced element-c; LASE-c). LASE-c was present in multiple alternatively spliced and truncated LAR transcripts. In contrast to LAR isoforms without LASE-c, levels of LAR transcripts and protein isoforms containing LASE-c were primarily present during development, suggesting a mechanism for developmental regulation of LAR function. In situ analysis demonstrated increasingly region- and cell-specific expression of LASE-c during maturation. Immunostaining revealed LASE-c-containing LAR protein along neurites and in growth cones. The discovery of highly regulated, temporospatial extracellular domain alternative splicing of LAR-type PTPase receptors points to a novel mechanism by which these receptors might influence network formation. Copyright 1998 Academic Press.

15.
Mol Cell Neurosci ; 10(5-6): 271-86, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9604206

RESUMO

Transgenic mice and Drosophila mutant studies demonstrate that the leukocyte common antigen-related (LAR) protein tyrosine phosphatase (PTPase) receptor is required for formation of neural networks. We assessed the hypothesis that alternative splicing of the LAR extracellular region contributes to this function by establishing temporospatial expression patterns of LAR isoforms containing an alternatively spliced extracellular nine amino acid segment (LAR alternatively spliced element-c; LASE-c). LASE-c was present in multiple alternatively spliced and truncated LAR transcripts. In contrast to LAR isoforms without LASE-c, levels of LAR transcripts and protein isoforms containing LASE-c were primarily present during development, suggesting a mechanism for developmental regulation of LAR function. In situ analysis demonstrated increasingly region- and cell-specific expression of LASE-c during maturation. Immunostaining revealed LASE-c-containing LAR protein along neurites and in growth cones. The discovery of highly regulated, temporospatial extracellular domain alternative splicing of LAR-type PTPase receptors points to a novel mechanism by which these receptors might influence network formation.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Isoenzimas/biossíntese , Proteínas do Tecido Nervoso , Neuritos/fisiologia , Proteínas Tirosina Fosfatases/biossíntese , Receptores de Superfície Celular/biossíntese , Animais , Animais Recém-Nascidos/genética , Mapeamento Encefálico , Células Cultivadas , Regulação para Baixo/genética , Feminino , Humanos , Isoenzimas/genética , Neuritos/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Especificidade de Órgãos/genética , Células PC12 , Estrutura Terciária de Proteína , Proteínas Tirosina Fosfatases/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores , Receptores de Superfície Celular/genética , Transcrição Gênica
16.
J Cereb Blood Flow Metab ; 17(6): 636-46, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9236720

RESUMO

The prolonged expression of the leucine zipper fos/jun immediate early genes (IEG) has been correlated with neuronal death after cerebral ischemia. In this study, the expression of six zinc finger IEG was examined using in situ hybridization in adult rats after middle cerebral artery occlusion (MCAO) with the suture model. NGFI-A, NGFI-B, NGFI-C, egr-2, egr-3, and Nurr1 mRNA were all induced throughout the ipsilateral cortex at 1 hour to 12 hours after MCAO. The cortical induction for most of the genes was greatest in the anterior cingulate and the anterior cerebral artery (ACA) and middle cerebral artery (MCA) transition zone. All of the zinc finger IEG were induced at 1 hour in all regions of hippocampus. NGFI-A and NGFI-B were induced in ipsilateral thalamus. Within areas of infarction, the basal IEG mRNA expression, and expression of the housekeeping gene cyclophilin A mRNA, decreased below control levels by 12 hours after the ischemia. Immediate early gene expression outside areas of infarction returned to control levels in most brain regions by 24 hours except for egr-3, which continued to be induced in the MCA/ ACA transition zone for 24 hours, and NGFI-A, which continued to be expressed in specific regions of the thalamus for 72 hours. The induction of these IEG in the cortex is likely caused by ischemia-induced cortical spreading depression, with the hippocampal and thalamic IEG induction being caused by activation of efferent cortical pathways to these regions. The prominent induction of NGFI-B, NGFI-C, egr-2, and egr-3 in the anterior cingulate cortex, the ACA/MCA transition zone, and medial striatum could reflect the ischemic regions around MCA infarcts. The prolonged NGFI-A expression observed in thalamus in this study, and in CA1 of hippocampus after global ischemia in the gerbil in a previous study, suggests that the prolonged NGFI-A, expression could be the result of or the cause of the delayed cell death. Prolonged NGFI-A expression, like c-fos and c-jun, seems to provide a marker for slowly dying neurons.


Assuntos
Isquemia Encefálica/genética , Proteínas Imediatamente Precoces/análise , Dedos de Zinco/genética , Isomerases de Aminoácido/genética , Animais , Proteínas de Transporte/genética , Núcleo Caudado/química , Córtex Cerebral/química , Proteínas de Ligação a DNA/análise , Proteína 1 de Resposta de Crescimento Precoce , Proteína 2 de Resposta de Crescimento Precoce , Endodesoxirribonucleases/genética , Expressão Gênica , Genes fos/genética , Genes jun/genética , Hipocampo/química , Hibridização In Situ , Dados de Sequência Molecular , Peptidilprolil Isomerase , Putamen/química , RNA Mensageiro/análise , Ratos , Tálamo/química , Fatores de Transcrição/análise , Córtex Visual/química
17.
J Cereb Blood Flow Metab ; 17(3): 241-56, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9119897

RESUMO

Kainic acid (KA) neurotoxicity was examined in transgenic (Tg) mice overexpressing human CuZn-superoxide dismutase (SOD-1). The doses of KA required to produce seizures, the severity of the seizures, and the regions damaged were similar in SOD-1 Tg and non-transgenic wild-type mice. Intraperitoneal KA injection induced seizure-related neuronal damage in the CA3 and CA1 regions of the hippocampus and in other regions of the brain in both SOD-1 Tg and wild-type mice. These damaged neurons were labeled with the terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling (TUNEL) technique up to 72 h, although no significant difference in the number of TUNEL-positive neurons was observed between SOD-1 Tg and wild-type mice. In situ hybridization showed that c-fos, c-jun, and hsp70 genes were expressed in the hippocampus, cortex, and other regions of the brain after KA treatment. The expression of these genes was maximal 1 to 4 h following KA treatment but persisted longer in the hippocampus and other regions in SOD-1 Tg compared with wild-type mice; however, cell death in the hippocampus, assessed using cresyl violet staining, was similar in SOD-1 Tg and wild-type mice. The data show that superoxide radicals modulate both immediate early gene and heat shock gene expression after KA-induced seizures. The prolonged expression of c-fos, c-jun, and hsp70 in SOD-1 Tg compared with wild-type mice may indicate that hippocampal neurons survive longer in SOD-1 Tg than in wild-type animals; however, cell death as well as the seizure threshold, seizure severity and the pattern of regional vulnerability were not affected substantially by increased levels of SOD in the brain.


Assuntos
Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Agonistas de Aminoácidos Excitatórios/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas Imediatamente Precoces/biossíntese , Ácido Caínico/toxicidade , Proteínas do Tecido Nervoso/biossíntese , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-jun/biossíntese , Superóxido Dismutase/fisiologia , Animais , Encéfalo/metabolismo , Cobre , Fragmentação do DNA , Radicais Livres , Genes Precoces , Genes fos , Genes jun , Proteínas de Choque Térmico HSP70/genética , Humanos , Proteínas Imediatamente Precoces/genética , Hibridização In Situ , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Estresse Oxidativo , Fagocitose , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/fisiologia , Convulsões/induzido quimicamente , Convulsões/genética , Superóxido Dismutase/biossíntese , Superóxido Dismutase/genética , Superóxidos/metabolismo , Zinco
18.
J Neurosci Res ; 47(3): 348-60, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9039657

RESUMO

A role in neural development for protein tyrosine phosphatase (PTPase) receptors has been suggested by the finding of aberrant neurite outgrowth in Drosophila mutants lacking functional leukocyte common antigen-related (LAR) PTPase receptors; however, PTPase functions in the mammalian nervous system remain to be established. In transgenic mice containing a gene trap in the LAR gene, only trace expression of full-length LAR transcripts was found. In these mice, the size of basal forebrain cholinergic neurons was significantly reduced and cholinergic innervation of the dentate gyrus was markedly decreased. These findings constitute the first demonstration of an aberrant neuronal phenotype in a mammalian PTPase mutant and support the hypothesis that LAR-type PTPase receptors function to establish and/or maintain neuronal networks.


Assuntos
Giro Denteado/citologia , Neurônios/fisiologia , Proteínas Tirosina Fosfatases/genética , Acetilcolina/fisiologia , Animais , Benzoxazinas , Biomarcadores , Northern Blotting , Tamanho Celular/fisiologia , Colina O-Acetiltransferase/metabolismo , Fibras Colinérgicas/química , Fibras Colinérgicas/enzimologia , Corantes , Giro Denteado/química , Feminino , Expressão Gênica/fisiologia , Genótipo , Masculino , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Neurônios/química , Neurônios/citologia , Oxazinas , Fenótipo , Prosencéfalo/citologia , Proteínas Tirosina Fosfatases/metabolismo , RNA Mensageiro/análise , Proteínas Tirosina Fosfatases Classe 4 Semelhantes a Receptores , Receptores de Superfície Celular/genética , Receptores de Fator de Crescimento Neural/análise
19.
Brain Res ; 745(1-2): 343-7, 1997 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-9037431

RESUMO

The present study investigated the mechanism of cellular degeneration within the striatum following administration of the mitochondrial toxin, 3-nitropropionic (3-NP) acid. Internucleosomal fragmentation typical of apoptosis was present in the DNA of cells from the striatum of 3-NP-treated rats. DNA fragmentation was also evident in this region by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling. The data suggest that striatal cells die by apoptosis following administration of 3-NP.


Assuntos
Apoptose/efeitos dos fármacos , Neostriado/citologia , Neurotoxinas/farmacologia , Propionatos/farmacologia , Animais , Fragmentação do DNA/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Histocitoquímica , Injeções Intraperitoneais , Masculino , Neostriado/efeitos dos fármacos , Neurotoxinas/administração & dosagem , Nitrocompostos , Propionatos/administração & dosagem , Ratos , Ratos Sprague-Dawley
20.
Acta Neurochir Suppl ; 70: 237-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9416333

RESUMO

3-Nitropropionic acid (3-NP), a mitochondrial toxin, induces apoptosis in the striatum. We wanted to determine if there was a relationship between mitochondrial dysfunction, disruption of the blood-brain barrier (BBB), and apoptosis. BBB disruption following intrastriatal injection of 3-NP was assessed by Evans blue leakage, brain water content, and by the expression of the 70 kDa heat shock protein (HSP70) and mRNA. Apoptosis was assessed by in situ terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling (TUNEL) and gel electrophoresis to detect internucleosomal DNA fragmentation. Microscopic evidence of Evans blue leakage due to 3-NP was present only 3 hr after injection. Both internucleosomal DNA fragmentation and TUNEL-labeling did not appear until 24 hr after injection. HSP70 (protein and mRNA) was also elevated by 24 hr. There was a quantitative increase in Evans blue leakage and brain water content due to 3-NP by 3 days after injection. Our results suggest that BBB disruption is an early event followed by increased HSP70 expression and apoptosis. We speculate that 3-NP damages endothelial cells, leading to vasogenic edema and apoptosis.


Assuntos
Barreira Hematoencefálica/fisiologia , Inibidores Enzimáticos/toxicidade , Proteínas de Choque Térmico HSP70/biossíntese , Neurotoxinas/toxicidade , Propionatos/toxicidade , Succinato Desidrogenase/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Corantes , Azul Evans , Extravasamento de Materiais Terapêuticos e Diagnósticos , Técnicas Genéticas , Masculino , Mitocôndrias/efeitos dos fármacos , Nitrocompostos , Ratos , Ratos Sprague-Dawley
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