Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
J Neurol Sci ; 461: 123027, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38805875

RESUMO

BACKGROUND: Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is a disease responsible for cognitive impairment in adult humans. It is caused by mutations in the colony stimulating factor 1 receptor gene (CSF1R) or alanyl-transfer (t) RNA synthetase 2 (AARS2) gene and affects brain white matter. Settlement of stages of the pathological brain lesions (Oyanagi et al. 2017) from the findings of brain imaging will be inevitably essential for prognostication. METHODS: MRI images of eight patients with ALSP were analyzed semiquantitatively. White matter degeneration was assessed on a scale of 0 to 4 (none, patchy, large patchy, confluent, and diffuse) at six anatomical points, and brain atrophy on a scale 0 to 4 (none, slight, mild, moderate, and severe) in four anatomical areas. The scores of the two assessments were then summed to give total MRI scores of 0-40 points. Based on the scores, the MRI features were classified as Grades (0-4). Regression analysis was applied to mutual association between mRS, white matter degeneration score, brain atrophy score, the total MRI score and disease duration. RESULTS: White matter degeneration score, brain atrophy score, and the total MRI score were significantly correlated with the disease duration. MRI Grades (2-4) based on the total MRI scores and the features of the images were well correlated with the pathological lesion stages (II - IV); i.e., 'large patchy' white matter degeneration in the frontal and parietal lobes (MRI Grade 2) corresponded to pathological Stage II, 'confluent' degeneration (Grade 3) to Stage III, and 'diffuse' degeneration (Grade 4) to Stage IV. CONCLUSION: MRI Grades (2-4) resulted from the total MRI scores were well correlated with the pathological lesion Stages (II - IV).


Assuntos
Encéfalo , Leucoencefalopatias , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/patologia , Leucoencefalopatias/genética , Adulto , Substância Branca/patologia , Substância Branca/diagnóstico por imagem , Neuroglia/patologia , Idoso , Atrofia/patologia
2.
eNeurologicalSci ; 22: 100310, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33553700

RESUMO

BACKGROUND: Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is an early onset dementia characterized by axonal loss in the cerebral white matter with swollen axons (spheroids). It had been reported that the preferential thinning and "focal lesions" of the corpus callosum were observed on T2-weighted MRI in ALSP patients. The present study aimed to reveal the pathologic basis of them in relation to brain lesion staging (I ~ IV: Oyanagi et al. 2017). METHODS: Seven autopsied brains of ALSP and five controls were neuropathologically examined. RESULTS: Even at Stage I, corpus callosum body showed evident atrophy, and the atrophy advanced with stage progression. Spheroid size and density were maximal at Stage II in both centrum semiovale and corpus callosum body, but spheroids were larger in corpus callosum body than in centrum semiovale. Microglia in the body at Stage II had a larger cytoplasm than those in centrum semiovale. But spheroids and microglia in the "focal lesions" were identical with those of centrum semiovale. CONCLUSION: Preferential thinning of corpus callosum was considered to be formed in relation to peculiar morphological alteration of microglia there in ALSP. Instead, "focal lesions" were formed in connection with the lesions in centrum semiovale.

3.
Brain Pathol ; 27(6): 748-769, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-27608278

RESUMO

The brains of 10 Japanese patients with adult onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) encompassing hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) and pigmentary orthochromatic leukodystrophy (POLD) and eight Japanese patients with Nasu-Hakola disease (N-HD) and five age-matched Japanese controls were examined neuropathologically with special reference to lesion staging and dynamic changes of microglial subsets. In both diseases, the pathognomonic neuropathological features included spherically swollen axons (spheroids and globules), axon loss and changes of microglia in the white matter. In ALSP, four lesion stages based on the degree of axon loss were discernible: Stage I, patchy axon loss in the cerebral white matter without atrophy; Stage II, large patchy areas of axon loss with slight atrophy of the cerebral white matter and slight dilatation of the lateral ventricles; Stage III, extensive axon loss in the cerebral white matter and dilatation of the lateral and third ventricles without remarkable axon loss in the brainstem and cerebellum; Stage IV, devastated cerebral white matter with marked dilatation of the ventricles and axon loss in the brainstem and/or cerebellum. Internal capsule and pontine base were relatively well preserved in the N-HD, even at Stage IV, and the swollen axons were larger with a higher density in the ALSP. Microglial cells immunopositive for CD68, CD163 or CD204 were far more obvious in ALSP, than in N-HD, and the shape and density of the cells changed in each stage. With progression of the stage, clinical symptoms became worse to apathetic state, and epilepsy was frequently observed in patients at Stages III and IV in both diseases. From these findings, it is concluded that (i) shape, density and subsets of microglia change dynamically along the passage of stages and (ii) increase of IBA-1-, CD68-, CD163- and CD204-immunopositive cells precedes loss of axons in ALSP.


Assuntos
Leucoencefalopatias/patologia , Lipodistrofia/patologia , Osteocondrodisplasias/patologia , Panencefalite Esclerosante Subaguda/patologia , Adulto , Atrofia/patologia , Autopsia , Axônios/patologia , Encéfalo/patologia , Feminino , Humanos , Japão , Leucoencefalopatias/diagnóstico , Lipodistrofia/diagnóstico , Masculino , Microglia/patologia , Pessoa de Meia-Idade , Neuroglia/patologia , Osteocondrodisplasias/diagnóstico , Panencefalite Esclerosante Subaguda/diagnóstico , Substância Branca/patologia
4.
J Neurol Sci ; 367: 349-55, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27423618

RESUMO

Clinical phenotypes of hereditary diffuse leukoencephalopathy with spheroids (HDLS), a familial progressive neurodegenerative disorder affecting the white matter of the brain, are heterogenous and may include behavioral and personality changes, memory impairment, parkinsonism, seizure, and spasticity. Thus, HDLS is frequently unrecognized and misdiagnosed. Heterozygous mutations located within the kinase domain of the gene encoding the colony-stimulating factor 1 receptor (CSF1R), a cell surface receptor with key roles in development and innate immunity, have been shown in HDLS. These different gene mutations may be related to the various clinical phenotypes. We report here a newly identified family with HDLS harboring a mutation in the CSF1R gene. We examined clinical and neuropathological features in three members of this family. These patients presented with affective incontinence, memory impairment, and executive dysfunction at onset, and revealed nonfluent aphasia, parkinsonism, and seizure as the disease progressed. We identified a novel CSF1R splice site mutation (c.2442+2T>C) in intron 18 for two of the patients. MRI of these patients revealed progressive, frontotemporal-predominant, confluent leukoencephalopathy. We also observed severe myelin loss, axonal degeneration, and abundant axonal spheroids, astrocytes, and microglia in the cerebral white matter, consistent with HDLS neuropathological features. Additionally, we identified atypical neuropathological findings for HDLS, including neuronal loss and gliosis with ballooned neurons and central chromatolysis in the frontal cortex and hippocampus. This report provides further evidence for the clinical and neuropathological heterogeneity of HDLS.


Assuntos
Leucoencefalopatias/genética , Mutação , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Adulto , Família , Evolução Fatal , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Íntrons , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/patologia , Masculino , Pessoa de Meia-Idade
5.
J Alzheimers Dis ; 45(2): 543-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25589723

RESUMO

BACKGROUND: 18F-FDG-PET is defined as a biomarker of neuronal injury according to the revised National Institute on Aging­Alzheimer's Association criteria. OBJECTIVE: The objective of this multicenter prospective cohort study was to examine the value of 18F-FDG-PET in predicting the development of Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI). METHODS: In total, 114 patients with MCI at 9 participating institutions underwent clinical and neuropsychological examinations, MRI, and 18F-FDG-PET at baseline. The cases were visually classified into predefined dementia patterns by three experts. Anautomated analysis for 18F-FDG-PET was also performed to calculate the PET score. Subjects were followed periodically for 3 years, and progression to dementia was evaluated. RESULTS: In 47% of the patients with MCI, progression of symptoms justified the clinical diagnosis of "probable AD". The PET visual interpretation predicted conversion to AD during 3-year follow-up with an overall diagnostic accuracy of 68%. Overall diagnostic accuracy of the PET score was better than that of PET visual interpretation at all follow-up intervals, and the optimized PET score threshold revealed the best performance at the 2-year follow-up interval with an overall diagnostic accuracy of 83%,a sensitivity of 70%, and a specificity of 90%. Multivariate logistic regression analysis identified the PET score as the most significant predictive factor distinguishing AD converters from non-converters. CONCLUSION: The PET score is the most statistically significant predictive factor for conversion from MCI to AD, and the diagnostic performance of the PET score is more promising for rapid converters over 2 years.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico , Fluordesoxiglucose F18/metabolismo , Tomografia por Emissão de Pósitrons , Idoso , Doença de Alzheimer/complicações , Disfunção Cognitiva/etiologia , Progressão da Doença , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
Neuromuscul Disord ; 22(8): 747-54, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22560514

RESUMO

Inclusion body myositis is an inflammatory myopathy characterized pathologically by rimmed vacuoles and the accumulation of amyloid-related proteins. Autopsy studies in these patients, including histochemical examinations of multiple skeletal muscles, have not yet been published. In this paper, we describe the autopsy findings of a patient with inclusion body myositis and hypertrophic cardiomyopathy. A 69-year-old man, who was a human T lymphotropic virus type 1 carrier, exhibited slowly progressive muscle weakness and atrophy, predominantly affecting the scapular, quadriceps femoris, and forearm flexor muscles. His disease course was more rapidly progressive than that typically observed; the patient died suddenly of arrhythmia 5 years after diagnosis. Autopsy findings revealed that multiple muscles, including the respiratory muscles, were involved. Longitudinal studies revealed an increased frequency of rimmed vacuoles and p62/sequestosome 1- and/or TAR DNA-binding protein 43-positive deposits in autopsied muscles, although the amount of inflammatory infiltrate appeared to be decreased. We speculated that muscle degeneration may be more closely involved in disease progression compared with autoimmunity. Genetic analysis revealed a myosin binding protein C3 mutation, which is reportedly responsible for familial hypertrophic cardiomyopathy. This mutation and human T lymphotropic virus type 1 infection may have affected the skeletal muscles of this patient.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/epidemiologia , Miosite de Corpos de Inclusão/diagnóstico , Miosite de Corpos de Inclusão/epidemiologia , Idoso , Autopsia , Cardiomiopatia Hipertrófica/genética , Proteínas de Transporte/genética , Comorbidade , Humanos , Masculino , Músculo Esquelético/patologia , Mutação/genética , Miocárdio/patologia , Miosite de Corpos de Inclusão/genética
7.
Brain Nerve ; 63(2): 109-18, 2011 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-21301035

RESUMO

Frontotemporal dementia (FTD) is a clinical entity that comprises at least two distinct diseases: Pick's disease with Pick bodies and frontotemporal lobar degeneration with tau-negative and ubiquitin-positive inclusions (FTLD-U). FTLD-U is now usually referred to as FTLD-TAR DNA binding protein 43 (TDP-43). FTLD-TDP-43, but not Pick's disease with tau-positive Pick bodies, is often associated with motor neuron disease (MND). More than 200 cases of this combined form, i.e., FTD-MND, have been reported in Japan. The neuropathological characteristics of MND in patients with FTD are essentially similar to the MND in patients without dementia. However the other characteristics of the combination of FTD and MND are such that the author has considered this disease a unique clinicopathological entity. These characteristics are as follows: (1) frontotemporal lobe-type dementia with insidious onset, usually in the presenile period; (2) neurogenic muscular wasting during the course of the illness [amyotrophic lateral sclerosis (ALS)]-- or [spinal progressive muscular atrophy (SPMA)]-like symptoms); (3) duration from the onset of illness to death is 2-5 years (average duration, 30.6 months); (4) both extrapyramidal symptoms and definite sensory deficiency are less commonly observed; (5) no characteristic abnormalities in the cerebrospinal fluid (CSF) or on the electroencephalogram (EEG) in screening tests; (6) no known parental consanguinity or familial occurrence; and (7) nonspecific mild-to-slight degenerative changes in the frontotemporal cortex, hypoglossal nuclei, spinal cord, and frequently in the substantia nigra. FTD-MND is characterized by ubiquitin-immunoreactive intraneuronal inclusions in cortical layers II and III and the hippocampal dentate granule cells. The occurrence of ubiquitin-positive, tau-negative and ubiquitinated TDP-43 positive inclusions could be the key to determining the pathological background of this disease. Further studies are required clinicopathological differentiation between FTD-MND and ALS-dementia (ALS-D).


Assuntos
Demência Frontotemporal , Doença dos Neurônios Motores , Sistema Nervoso Central/patologia , Proteínas de Ligação a DNA/genética , Diagnóstico por Imagem , Demência Frontotemporal/diagnóstico , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Demência Frontotemporal/fisiopatologia , Humanos , Doença dos Neurônios Motores/diagnóstico , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/patologia , Doença dos Neurônios Motores/fisiopatologia , Síndrome
9.
Prog Neuropsychopharmacol Biol Psychiatry ; 34(3): 532-6, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20170698

RESUMO

Yokukansan (YKS) is used frequently against behavioral and psychological symptoms of dementia (BPSD) together with donepezil in patients with Alzheimer's disease (AD). Here, we investigated the efficacy and safety of YKS in patients with AD in a non-blinded, randomized, parallel-group comparison study. Patients who had at least one symptom score of four or more on the Neuropsychiatric Inventory (NPI) subscales were enrolled in the study. The subjects were randomly assigned to the YKS-treated group (YKS/donepezil combination therapy group) and the non-YKS-treated group (donepezil monotherapy group). TSUMURA Yokukansan (TJ-54, 7.5g, t.i.d.) was administered in a four-week study treatment period. The subjects were evaluated twice at the start (Week 0) and completion (Week 4) of the study treatment in terms of NPI, Mini-Mental Status Examination (MMSE), Disability Assessment for Dementia (DAD), Zarit Burden Interview, and Self-rating Depression Scale (SDS). The efficacy analysis was performed in 29 patients (YKS-treated group) and 32 patients (non-YKS-treated group). The NPI total score improved significantly more in the YKS-treated group than in the non-YKS-treated group. In the NPI subscales of agitation/aggression and irritability/lability, the YKS-treated group showed significantly greater improvement than the non-YKS-treated group, but no statistically significant improvement was seen with YKS in the other subscales. There were no significant differences between the YKS-treated group and the non-YKS-treated group in MMSE, DAD, Zarit Burden Interview and SDS. No adverse reactions were noted in either group. The results of this study showed that YKS is safe and effective in the treatment of BPSD in AD patients.


Assuntos
Sintomas Comportamentais/tratamento farmacológico , Sintomas Comportamentais/etiologia , Demência/complicações , Medicamentos de Ervas Chinesas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Demência/tratamento farmacológico , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Resultado do Tratamento
10.
Prog Neuropsychopharmacol Biol Psychiatry ; 34(3): 541-5, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20184936

RESUMO

The efficacy and safety of the kampo medicine Yokukansan (YKS, TJ-54) in the treatment of behavioral and psychological symptoms of dementia (BPSD) were investigated in patients with Alzheimer's disease (AD) in an open-label study. This study included 26 patients who had been diagnosed as having AD and were not treated with donepezil hydrochloride. These patients were administered YKS (7.5g/day) for four weeks to investigate the changes in neuropsychological test results and care burden in the period from the start to completion of the study treatment. The Neuropsychiatric Inventory (NPI) was used for evaluation of BPSD, the Mini-Mental State Examination (MMSE) for evaluation of cognitive functions, the Zarit burden interview for evaluation of the caregiver's burden, Disability Assessment of Dementia (DAD) for evaluation of activities of daily living (ADL) and Self-Rating Depression Scale (SDS) for evaluation of the caregiver's depression. No significant change was seen in MMSE and DAD after four weeks of treatment, but the mean NPI total score decreased significantly. Furthermore, among the NPI subscales, a statistically significant decrease in score was not seen, however, a clinically significant decrease was seen in terms of hallucinations, agitation, anxiety, irritability or abnormal behavior. No significant changes were seen in caregiver's burden after four weeks of treatment. No serious adverse reactions to YKS were observed. The results of this study suggested that YKS may be an effective and well-tolerated drug in the treatment of BPSD in AD patients.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Sintomas Comportamentais/tratamento farmacológico , Sintomas Comportamentais/etiologia , Medicamentos de Ervas Chinesas/uso terapêutico , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Donepezila , Feminino , Humanos , Indanos/uso terapêutico , Masculino , Entrevista Psiquiátrica Padronizada , Testes Neuropsicológicos , Nootrópicos/uso terapêutico , Piperidinas/uso terapêutico , Estatísticas não Paramétricas
11.
Neuropathology ; 29(6): 649-54, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19780984

RESUMO

Non-Alzheimer-type dementias occur in association with a variety of pathological conditions that include a group of diseases characterized by atrophy of the frontal and temporal lobes. Frontotemporal dementia (FTD) is a clinical entity that comprises at least two distinct diseases: Pick's disease with Pick bodies and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). The vast majority of FTLD-U is now referred to as FTLD-TDP, following the recent discovery of TAR DNA-binding protein of 43 kDa (TDP-43) as the major constituent of the ubiquitin-positive inclusions. FTLD-TDP, but not Pick's disease with Pick bodies, is often associated with motor neuron disease (MND). MND is a group of diseases in which the central nervous system lesions were long believed to be confined to the motor neuron system. In other words, MND was not considered to be associated with other neurological symptoms such as dementia. Nevertheless, more than 200 FTD cases associated with clinical MND have been reported in Japan since 1964. Neuropathologically, MND in such FTD cases was essentially similar to MND in cases without dementia. The combination of FTD and MND was so characteristic that we considered these cases comprise a unique clinicopathological subgroup of FTD. FTD with MND and the classical MND without dementia share the occurrence of ubiquitinated TDP-43-positive inclusions, a finding that could be a key to unlock the pathological backgrounds of both diseases.


Assuntos
Encéfalo/patologia , Demência Frontotemporal/complicações , Doença dos Neurônios Motores/complicações , Mapeamento Encefálico , Demência Frontotemporal/patologia , Humanos , Corpos de Inclusão/patologia , Doença dos Neurônios Motores/patologia , Doença de Pick/complicações , Doença de Pick/patologia
12.
Psychiatry Res ; 164(1): 58-72, 2008 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-18804967

RESUMO

Using [(18)F]fluoro-deoxy-glucose-PET, we studied relative metabolic changes due to age- and gender-related differences in the brain of 126 healthy subjects from their twenties to seventies. We used a data-extraction technique, the three-dimensional stereotactic surface projections (3D-SSP) method, to measure metabolic changes with fewer effects of regional anatomic variances. Simple regression analysis revealed significant age-related increases in relative metabolic values in the parahippocampal and amygdala regions in both sexes in their twenties to forties, and significant age-related decreases in both sexes in their fifties to seventies. Relative values in the frontal lobe showed significant age-related decreases in both sexes in their twenties to forties, but these effects were not seen in subjects in their fifties to seventies. Significant gender differences in correlation coefficients of relative values with age were shown in the parahippocampal, primary sensorimotor, temporal, thalamus and vermis regions in subjects in their 20s to 40s, but disappeared in subjects in their twenties to forties, but were not apparent in subjects in their fifties to seventies except in the vermis. Males in their twenties to sixties and females in their fifties showed significant laterality in relative values in the temporal lobes. Our study demonstrated age- and gender-related differences in glucose metabolism in healthy subjects.


Assuntos
Envelhecimento/fisiologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Glucose/metabolismo , Nível de Saúde , Adulto , Idoso , Atrofia/metabolismo , Atrofia/patologia , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Giro Para-Hipocampal/metabolismo , Giro Para-Hipocampal/patologia , Giro Para-Hipocampal/fisiopatologia , Fatores Sexuais , Lobo Temporal/metabolismo , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia
13.
Brain Res ; 1025(1-2): 29-34, 2004 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-15464741

RESUMO

Recent data from several groups suggest that the primary mechanism of amyloid beta-protein (Abeta) neurotoxicity may be mediated by free radicals. To evaluate this hypothesis, our aim is to make the mechanism of Abeta neurotoxicity clear, especially in the formation of free radicals. In this study, rat pheochromocytoma (PC12) cells were exposed to Abeta25-35 and confirmed free radical generations using two kinds of spin trap agents, 5,5-dimethyl-1-pyrroline-N-oxide; DMPO and alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone; POBN. DMPO spin adduct revealed that hydroxyl radical (OH), while POBN spin adduct identified a lipid radical (L) as electron paramagnetic resonance (EPR) evidence of lipid peroxidation in the process of cell damage by Abeta25-35 exposure. An Abeta cytotoxicity assay also was performed by using WST-8 reduction system and histochemical analysis. These analyses showed cell damage induced by Abeta. This study provides EPR evidence that Abeta neurotoxicity is derived from hydrogen abstraction from polyunsaturated lipid acid by hydroxyl radical as a cause of lipid peroxidation.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Radical Hidroxila/metabolismo , Peroxidação de Lipídeos/fisiologia , Fragmentos de Peptídeos/farmacologia , Peptídeos beta-Amiloides/toxicidade , Animais , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radical Hidroxila/toxicidade , Células PC12 , Fragmentos de Peptídeos/toxicidade , Ratos
14.
18.
Exp Brain Res ; 147(2): 219-26, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12410337

RESUMO

Kainic acid (KA) induces seizures and degeneration in CA1 of the ventral hippocampus, though its mechanism of action is unknown. We used KA to induce seizures in freely moving rats prepared for in vivo microdialysis with probe placement, and then measured extracellular glutamate with an online fluorometric detector. Generation of free radicals was monitored by electron paramagnetic resonance (EPR) spectroscopy coupled with perfusion of the spin-trapping agent, alpha-(4-pyridyl- N-oxide)- N- tert-butylnitrone (POBN). Regional antioxidant efficacy was measured by observing the eliminating ratio of nitroxide radicals, using 3-carbamoyl-2, 2, 5, 5-tetramethylpyrrolidine-1-oxyl (carbamoyl-PROXYL) applied exogenously from the probe. Increased levels of extracellular glutamate observed at the initiation of KA-induced seizures appear to be associated with generation of lipid free radicals and with a decrease in residual antioxidant effects. These data suggest that collapse of the redox state in the hippocampus, the region most vulnerable to injury from seizure activity, may be critical in the regional injury induced by seizures. Further, we propose that the functional failure of glutamate transporters due to oxidative stress results in high levels of extracellular glutamate during sustained generalized seizures induced with KA.


Assuntos
Radicais Livres/metabolismo , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Estado Epiléptico/metabolismo , Animais , Espaço Extracelular/metabolismo , Ácido Caínico , Masculino , Microdiálise , Ratos , Ratos Wistar , Estado Epiléptico/induzido quimicamente
19.
Dement Geriatr Cogn Disord ; 14(3): 113-22, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12218253

RESUMO

We developed a new enzyme-linked immunosorbent assay (ELISA) system using antibodies against intact human laminin, laminin alpha(5)-chain, laminin beta(1)-chain, laminin gamma(1)-chain and laminin alpha(1)-chain peptide (YFQRYLI). Using this ELISA, we measured the anti-laminin immunoreactivity levels in the cerebrospinal fluid (CSF) obtained from patients with Alzheimer's disease (AD), vascular dementia (VaD), and other disorders. The present study showed the levels of certain laminins in CSF to demonstrate significant differences in the chain levels in different dementias. The AD group showed a significantly lower level of anti-laminin gamma(1) immunoreactivity. The late-onset AD group showed significantly elevated anti-laminin alpha(1)-peptide (YFQRYLI) immunoreactivity levels in comparison with the early-onset AD group and controls. On the other hand, the VaD group showed significantly higher levels of anti-intact human laminin and anti-laminin beta(1) immunoreactivity. The assays of anti-laminin immunoreactivity levels in CSF provided an efficient sensitivity (85.0%) and specificity (93.7%) for the diagnosis of AD by using the ratio of tau to anti-intact human laminin immunoreactivity levels. These results suggest that CSF laminin or its derivatives may correlate with the pathogenesis of AD and VaD, and the prevention of the proteolytic activity may be an effective therapeutic method for either preventing or slowing down the progression of AD. Furthermore, it was shown that performing ELISA for CSF laminins may prove to be useful for detecting the biological markers of AD and VaD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Demência Vascular/líquido cefalorraquidiano , Laminina/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Demência Vascular/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Pessoa de Meia-Idade , Proteínas tau/líquido cefalorraquidiano
20.
Brain Res Mol Brain Res ; 104(2): 120-6, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12225864

RESUMO

In order to investigate the molecular mechanism underlying high seizure susceptibility of GLAST knockout mice, we carried out Western blotting for the expression of GLT-1, EAAC-1, and several kinds of glutamate receptors in the hippocampus and the cortex. Although no significant difference was observed between GLAST (+/+) and (-/-) mice in terms of expression of GLT-1 and EAAC-1 in the hippocampus, these proteins were over-expressed in the frontal cortex in GLAST (-/-) mice (GLT-1, about 210% increase; EAAC-1, about 180% increase). Expression of hippocampal Glu-R1 and Glu-R2 in GLAST (-/-) mice was remarkably increased (Glu-R1, about 140% increase; Glu-R2, about 160% increase), while Glu-R3 and NMDA receptors levels (NMDA-R1, 2A and 2B) were equal to those in control. Cortical levels of Glu-R1, -R2 and -R3 receptors in GLAST (-/-) mice were remarkably decreased (Glu-R1, about 60% decrease; Glu-R2, about 60% decrease; Glu-R3, about 70% decrease), while NMDA receptors were remarkably increased in comparison to those in GLAST (+/+) mice (N-R1, about 150% increase; N-R2A, about 150% increase; N-R2B, about 140% increase). These data suggest that the increased susceptibility to seizures in GLAST (-/-) mice might be derived from increased expression of Glu-R1 in the hippocampus coupled with decreased cortical expression of Glu-R2 and increased NMDA-R1 and -2A, -2B expression.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/deficiência , Regulação para Baixo/genética , Epilepsia/metabolismo , Lobo Frontal/metabolismo , Hipocampo/metabolismo , Receptores de Glutamato/metabolismo , Sistema X-AG de Transporte de Aminoácidos/genética , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Epilepsia/genética , Epilepsia/fisiopatologia , Transportador 1 de Aminoácido Excitatório , Transportador 2 de Aminoácido Excitatório/metabolismo , Feminino , Lobo Frontal/fisiopatologia , Predisposição Genética para Doença/genética , Proteínas de Transporte de Glutamato da Membrana Plasmática , Ácido Glutâmico/metabolismo , Hipocampo/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de AMPA/metabolismo , Receptores de Ácido Caínico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Simportadores/metabolismo , Transmissão Sináptica/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA