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1.
J Neuropathol Exp Neurol ; 69(5): 442-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20418782

RESUMO

Cerebrovascular pathology is a major cause of stroke and mortality. Studies on prevalence of cerebrovascular pathologies in dementia with Lewy bodies (DLBs) and Parkinson disease (PD) patients are scarce and contradictory. We aimed to determine the prevalence and severity of cerebrovascular pathologies in DLB and PD and to analyze their relationship to LB pathology. The prevalence and severity of atherosclerosis in the circle of Willis, cerebral amyloid angiopathy, cerebral infarcts, hemorrhages, small-vessel disease, white matter lesions, including the Consortium to Establish a Registry for Alzheimer Disease (CERAD) protocol as well as Braak neurofibrillary tangle stages for AD pathology were analyzed in autopsy-verified DLB (n = 13), PD (n = 102), and control subjects (n = 53). In all patient groups, the extent of LB pathology was inversely correlated to the severity of most vascular pathologies (atherosclerosis, infarcts, and small-vessel disease; all p < 0.05). By contrast, cerebral amyloid angiopathy, CERAD, and Braak neurofibrillary tangle stages were positively correlated with LB pathology (p < 0.05). Whereas the overall prevalence and severity of small-vessel disease, infarcts, hemorrhages, and white matter lesions were comparable among both disease groups, the extents of atherosclerosis, cerebral amyloid angiopathy, CERAD, and Braak neurofibrillary tangle stages were significantly higher in DLB than in those of PD patients (p < 0.05). Microinfarcts were statistically more prevalent in each patient group than in controls, whereas gross infarcts predominated in controls (p < 0.05 each). In conclusion, DLB and PD patients with advanced LB pathology were less likely to show severe cerebrovascular disease or history of stroke.


Assuntos
Transtornos Cerebrovasculares/etiologia , Corpos de Lewy/patologia , Doença por Corpos de Lewy/complicações , Doença por Corpos de Lewy/patologia , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides/metabolismo , Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Estudos de Casos e Controles , Angiografia Cerebral/métodos , Distribuição de Qui-Quadrado , Círculo Arterial do Cérebro/patologia , Feminino , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia , Exame Neurológico/métodos , Doença de Parkinson/complicações , Doença de Parkinson/patologia , Análise de Componente Principal/métodos , Estudos Retrospectivos
2.
Acta Neuropathol ; 115(6): 599-609, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18369648

RESUMO

Cerebral amyloid angiopathy (CAA) is characterized by the deposition of the amyloid beta-protein (A beta) within cerebral vessels. The involvement of different brain areas in CAA follows a hierarchical sequence similar to that of Alzheimer-related senile plaques. Alzheimer's disease patients frequently exhibit CAA. The expansion of CAA in AD often shows the pattern of full-blown CAA. The deposition of A beta within capillaries distinguishes two types of CAA. One with capillary A beta-deposition is characterized by a strong association with the apolipoprotein E (APOE) epsilon 4 allele and by its frequent occurrence in Alzheimer's disease cases whereas the other one lacking capillary A beta-deposits is not associated with APOE epsilon 4. Capillary CAA can be seen in every stage of CAA or AD-related A beta-deposition. AD cases with capillary CAA show more widespread capillary A beta-deposition than non-demented cases as well as capillary occlusion. In a mouse model of CAA, capillary CAA was associated with capillary occlusion and cerebral blood flow disturbances. Thus, blood flow alterations with subsequent hypoperfusion induced by CAA-related capillary occlusion presumably point to a second mechanism in which A beta adversely affects the brain in AD in addition to its direct neurotoxic effects.


Assuntos
Doença de Alzheimer/complicações , Angiopatia Amiloide Cerebral/complicações , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amiloide/metabolismo , Apolipoproteína E4/genética , Angiopatia Amiloide Cerebral/genética , Angiopatia Amiloide Cerebral/metabolismo , Angiopatia Amiloide Cerebral/patologia , Humanos
3.
Proteomics ; 8(6): 1221-36, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18283660

RESUMO

Accumulation of proteins in inclusions in neurological disorders is partly due to dysfunction of the ubiquitin-proteasome system. Proteasomal dysfunction may be caused by misexpression of one or more of its subunits. A large number of antibodies reactive with proteasome subunits were screened on material from patients exhibiting tau- and synucleinopathies. Many antisera against proteasomal subunits (11S activator, 19S regulator ATPase/non-ATPase, and 20S alpha and beta resulted in a distinct nuclear and/or cytoplasmic staining of the entorhinal-hippocampal area and the temporal cortex of Alzheimer's disease (AD) patients. In particular an antibody directed against 19S regulator ATPase subunit 6b (S6b) specifically stained the neurofibrillary tangles and dystrophic neurites in AD, Down syndrome and aged nondemented controls. In other tauopathies (Pick's disease, frontotemporal dementia, progressive supranuclear palsy and argyrophilic grain disease), neuronal and/or glial inclusions were also S6b immunoreactive. In contrast, in synucleinopathies (Lewy body disease (LBD) and multiple system atrophy) no S6b staining was seen. Real time quantitative PCR on the temporal cortex of AD patients revealed a significant increase in S6b subunit mRNA. This increase was not found in the gyrus cinguli anterior of patients with LBD. This differential expression of S6b most likely will result in different proteomic patterns. Here we present evidence to show that S6b coexists with a reporter for proteasomal dysfunction (ubiquitin(+1)), and we conclude that S6b transcript up-regulation and the dysfunction in tauopathies may be functionally related.


Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Proteômica/métodos , Sinucleínas/metabolismo , Tauopatias/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Anticorpos/imunologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Modelos Biológicos , Atrofia de Múltiplos Sistemas/metabolismo , Atrofia de Múltiplos Sistemas/patologia , Doença de Pick/metabolismo , Doença de Pick/patologia , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/imunologia , Subunidades Proteicas/genética , Subunidades Proteicas/imunologia , Subunidades Proteicas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tauopatias/patologia , Lobo Temporal/metabolismo , Lobo Temporal/patologia
4.
Acta Neuropathol ; 113(4): 421-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17294202

RESUMO

Clinical signs frequently recognized in early phases of sporadic Parkinson's disease (PD) may include autonomic dysfunctions and the experience of pain. Early disease-related lesions that may account for these symptoms are presently unknown or incompletely known. In this study, immunocytochemistry for alpha-synuclein was used to investigate the first relay stations of the pain system as well as parasympathetic and sympathetic pre- and postganglionic nerve cells in the lower brainstem, spinal cord, and coeliac ganglion in 100 microm polyethylene glycol embedded sections from six autopsy individuals, whose brains were staged for PD-associated synucleinopathy. Immunoreactive inclusions were found for the first time in spinal cord lamina I neurons. Lower portions of the spinal cord downwards of the fourth thoracic segment appeared to be predominantly affected, whereas the spinal trigeminal nucleus was virtually intact. Additional involvement was seen in parasympathetic preganglionic projection neurons of the vagal nerve, in sympathetic preganglionic neurons of the spinal cord, and in postganglionic neurons of the coeliac ganglion. The known interconnectivities between all of these components offer a possible explanation for their particular vulnerability. Lamina I neurons (pain system) directly project upon sympathetic relay centers, and these, in turn, exert influence on the parasympathetic regulation of the enteric nervous system. This constellation indicates that physical contacts between vulnerable regions play a key role in the pathogenesis of PD.


Assuntos
Gânglios Parassimpáticos/patologia , Gânglios Simpáticos/patologia , Neurônios/patologia , Doença de Parkinson/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/metabolismo , Doença de Parkinson/complicações , Sistema Nervoso Periférico , Células do Corno Posterior/patologia , alfa-Sinucleína/metabolismo
5.
Brain Res Rev ; 53(2): 235-49, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17014911

RESUMO

The spinocerebellar ataxias type 2 (SCA2) and type 3 (SCA3) are progressive, currently untreatable and ultimately fatal ataxic disorders, which belong to the group of neurological disorders known as CAG-repeat or polyglutamine diseases. Since knowledge regarding the involvement of the central somatosensory system in SCA2 and SCA3 currently is only fragmentary, a variety of somatosensory disease signs remained unexplained or widely misunderstood. The present review (1) draws on the current knowledge in the field of neuroanatomy, (2) describes the anatomy and functional neuroanatomy of the human central somatosensory system, (3) provides an overview of recent findings regarding the affection of the central somatosensory system in SCA2 and SCA3 patients, and (4) points out the underestimated pathogenic role of the central somatosensory system for somatosensory and somatomotor disease symptoms in SCA2 and SCA3. Finally, based on recent findings in the research fields of neuropathology and neural plasticity, this review supports currently applied and recommends further neurorehabilitative approaches aimed at maintaining, improving, and/or recovering adequate somatomotor output by enforcing and changing somatosensory input in the very early clinical stages of SCA2 and SCA3.


Assuntos
Sistema Nervoso Central/fisiopatologia , Doença de Machado-Joseph/fisiopatologia , Doença de Machado-Joseph/reabilitação , Sensação/fisiologia , Ataxias Espinocerebelares/fisiopatologia , Ataxias Espinocerebelares/reabilitação , Animais , Sistema Nervoso Central/patologia , Humanos , Modelos Neurológicos , Vias Neurais/patologia , Vias Neurais/fisiopatologia
6.
PLoS Biol ; 4(12): e417, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17147470

RESUMO

Disease-associated misfolded proteins or proteins damaged due to cellular stress are generally disposed via the cellular protein quality-control system. However, under saturating conditions, misfolded proteins will aggregate. In higher eukaryotes, these aggregates can be transported to accumulate in aggresomes at the microtubule organizing center. The fate of cells that contain aggresomes is currently unknown. Here we report that cells that have formed aggresomes can undergo normal mitosis. As a result, the aggregated proteins are asymmetrically distributed to one of the daughter cells, leaving the other daughter free of accumulated protein damage. Using both epithelial crypts of the small intestine of patients with a protein folding disease and Drosophila melanogaster neural precursor cells as models, we found that the inheritance of protein aggregates during mitosis occurs with a fixed polarity indicative of a mechanism to preserve the long-lived progeny.


Assuntos
Polaridade Celular , Células Eucarióticas/citologia , Células Eucarióticas/metabolismo , Proteínas/metabolismo , Animais , Células Cultivadas , Cricetinae , Drosophila melanogaster , Humanos , Mitose , Ácido Poliglutâmico/metabolismo
7.
J Neurosci ; 26(44): 11474-86, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17079677

RESUMO

Ataxin-3 (AT3), the disease protein in spinocerebellar ataxia type 3 (SCA3), has been associated with the ubiquitin-proteasome system and transcriptional regulation. Here we report that normal AT3 binds to target DNA sequences in specific chromatin regions of the matrix metalloproteinase-2 (MMP-2) gene promoter and represses transcription by recruitment of the histone deacetylase 3 (HDAC3), the nuclear receptor corepressor (NCoR), and deacetylation of histones bound to the promoter. Both normal and expanded AT3 physiologically interacted with HDAC3 and NCoR in a SCA3 cell model and human pons tissue; however, normal AT3-containing protein complexes showed increased histone deacetylase activity, whereas expanded AT3-containing complexes had reduced deacetylase activity. Consistently, histone analyses revealed an increased acetylation of total histone H3 in expanded AT3-expressing cells and human SCA3 pons. Expanded AT3 lost the repressor function and displayed altered DNA/chromatin binding that was not associated with recruitment of HDAC3, NCoR, and deacetylation of the promoter, allowing aberrant MMP-2 transcription via the transcription factor GATA-2. For transcriptional repression normal AT3 cooperates with HDAC3 and requires its intact ubiquitin-interacting motifs (UIMs), whereas aberrant transcriptional activation by expanded AT3 is independent of the UIMs but requires the catalytic cysteine of the ubiquitin protease domain. These findings demonstrate that normal AT3 binds target promoter regions and represses transcription of a GATA-2-dependent target gene via formation of histone-deacetylating repressor complexes requiring its UIM-associated function. Expanded AT3 aberrantly activates transcription via its catalytic site and loses the ability to form deacetylating repressor complexes on target chromatin regions.


Assuntos
Cromatina/metabolismo , Histona Desacetilases/metabolismo , Histonas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Transcrição Gênica/fisiologia , Motivos de Aminoácidos , Animais , Ataxina-3 , Linhagem Celular , Cromatina/genética , Feminino , Histona Desacetilases/genética , Histonas/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Ligação Proteica/genética , Ratos , Proteínas Repressoras/genética , Ubiquitina/metabolismo
8.
Mov Disord ; 21(12): 2042-51, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17078043

RESUMO

The synucleinopathy known as sporadic Parkinson's disease (PD) is a multisystem disorder that severely damages predisposed nerve cell types in circumscribed regions of the human nervous system. A recent staging procedure for the inclusion body pathology associated with PD proposes that, in the brain, the pathological process (formation of proteinaceous intraneuronal Lewy bodies and Lewy neurites) begins at two sites and continues in a topographically predictable sequence in six stages, during which components of the olfactory, autonomic, limbic, and somatomotor systems become progressively involved. In stages 1 to 2, the Lewy body pathology is confined to the medulla oblongata/pontine tegmentum and anterior olfactory structures. In stages 3 to 4, the substantia nigra and other nuclei of the basal mid- and forebrain become the focus of initially subtle and, then, severe changes. During this phase, the illness probably becomes clinically manifest. In the final stages 5 to 6, the lesions appear in the neocortex. This cross-sectional study originally was performed on 168 autopsy cases using material from 69 incidental cases and 41 clinically diagnosed PD patients as well as 58 age- and gender-matched controls. Here, the staging hypothesis is critically reconsidered and discussed.


Assuntos
Corpos de Inclusão/patologia , Doença de Parkinson/patologia , Animais , Progressão da Doença , Humanos , Doença de Parkinson/fisiopatologia
9.
Brain Pathol ; 16(3): 218-27, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16911479

RESUMO

In the last years progress has been made regarding the involvement of the thalamus during the course of the currently known polyglutamine diseases. Although recent studies have shown that the thalamus consistently undergoes neurodegeneration in Huntington's disease (HD) and spinocerebellar ataxia type 2 (SCA2) it is still unclear whether it is also a consistent target of the pathological process of spinocerebellar ataxia type 3 (SCA3). Accordingly we studied the thalamic pathoanatomy and distribution pattern of ataxin-3 immunopositive neuronal intranuclear inclusions (NI) in nine clinically diagnosed and genetically confirmed SCA3 patients and carried out a detailed statistical analysis of our findings. During our pathoanatomical study we disclosed (i) a consistent degeneration of the ventral anterior, ventral lateral and reticular thalamic nuclei; (ii) a degeneration of the ventral posterior lateral nucleus and inferior and lateral subnuclei of the pulvinar in the majority of these SCA3 patients; and (iii) a degeneration of the ventral posterior medial and lateral posterior thalamic nuclei, the lateral geniculate body and some of the limbic thalamic nuclei in some of them. Upon immunocytochemical analysis we detected NI in all of the thalamic nuclei of all of our SCA3 patients. According to our statistical analysis (i) thalamic neurodegeneration and the occurrence of ataxin-3 immunopositive thalamic NI was not associated with the individual length of the CAG-repeats in the mutated SCA3 allele, the patients age at disease onset and the duration of SCA3 and (ii) thalamic neurodegeneration was not correlated with the occurrence of ataxin-3 immunopositive thalamic NI. This lack of correlation may suggest that ataxin-3 immunopositive NI are not immediately decisive for the fate of affected nerve cells but rather represent unspecific and pathognomonic morphological markers of SCA3.


Assuntos
Corpos de Inclusão Intranuclear/patologia , Doença de Machado-Joseph/patologia , Degeneração Neural/patologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/patologia , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Tálamo/patologia , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Ataxina-3 , Feminino , Humanos , Imuno-Histoquímica , Corpos de Inclusão Intranuclear/metabolismo , Doença de Machado-Joseph/metabolismo , Masculino , Pessoa de Meia-Idade , Degeneração Neural/metabolismo , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Tálamo/metabolismo , Repetições de Trinucleotídeos/genética
10.
J Neuropathol Exp Neurol ; 65(2): 116-23, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16462203

RESUMO

Previous studies investigating the association between apolipoprotein E (APOE) genotypes and Parkinson disease (PD) have yielded conflicting results, and only a few have addressed APOE as a possible determinant of PD pathology. Therefore, we aimed to evaluate the relationship between APOE and PD as well as APOE and PD pathology. We studied 108 pathologically verified patients with PD and 108 controls pair-matched for age and gender. Allele frequencies of APOE differed between patients with PD and controls (p = 0.02). The frequency of epsilon4 allele increased (p = 0.01), whereas that of epsilon3 allele decreased with advancing PD pathology (p = 0.002). Only age of PD onset was an independent predictor for the rate of progression of PD pathology in which late-onset patients appeared to reach end point PD pathology more rapidly than early-onset patients (p = 0.001). In conclusion, our findings suggest that APOE may express its effect on the risk of PD by modifying the occurrence of PD pathology, but age of PD onset seems to be the principal determinant of the progression rate of PD pathology.


Assuntos
Apolipoproteínas E , Doença de Parkinson , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
11.
Acta Neuropathol ; 111(2): 150-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16453142

RESUMO

Clinical studies have identified white matter (WM) lesions as hyperintensive regions in the MRI images of elderly patients. Since a cerebrovascular origin was attributed to such lesions, the present analysis set out to define the microvascular histopathologic changes in the periventricular WM in the aged. Post-mortem samples of the frontal, parietal, and occipital periventricular WM of 40-90-year-old subjects were prepared for quantitative light and electron microscopy. Light microscopic examination revealed microvascular fibrohyalinosis as the most common type of microvascular damage in the elderly. Ultrastructural analysis identified the microvascular thickening as collagen deposits affecting the basement membrane. The vascular density did not correlate with the age. The basement membrane pathology significantly increased, while the number of intact microvessels gradually decreased, with advancing age in the frontal and occipital WM. Finally, peripheral atherosclerosis coincided with massive microvascular fibrosis, particularly in the frontal WM. Our results demonstrate an age-related microvascular degeneration in the periventricular WM, which may contribute to the development of WM lesions by hindering a sufficient supply of nutrients to the affected WM sites. Furthermore, the data accord with previous observations identifying the frontal lobe as the site at which WM vulnerability is most pronounced. Finally, atherosclerosis in large, peripheral vessels is considered to be a predictive marker of microvascular pathology in the WM.


Assuntos
Envelhecimento , Encéfalo/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Basal/metabolismo , Membrana Basal/ultraestrutura , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Vasos Sanguíneos/ultraestrutura , Cadáver , Ventrículos Cerebrais , Colágeno/metabolismo , Feminino , Fibrose , Lobo Frontal/irrigação sanguínea , Humanos , Arteriosclerose Intracraniana/patologia , Masculino , Microcirculação , Microscopia Eletrônica , Pessoa de Meia-Idade , Lobo Occipital/irrigação sanguínea
12.
Biomaterials ; 27(11): 2390-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16343614

RESUMO

In this study, the development is described of a tissue-engineered construct mimicking the structure of a natural blood vessel. Smooth muscle cells (SMC) were cultured under pulsatile flow conditions in porous tubular scaffolds composed of crosslinked type I insoluble collagen and insoluble elastin. Under these dynamic culture conditions, average wall shear rate, systolic and diastolic pressures and pressure wave-forms comparable to conditions in the human carotid artery were obtained. Culturing of SMC in tubular scaffolds under dynamic conditions resulted in enhanced tissue formation compared to static conditions. Higher SMC numbers, a more homogeneous distribution of SMC throughout the scaffolds and higher collagen mRNA expression levels were found when cells were cultured under dynamic compared to static conditions. mRNA expression levels of markers of proliferation and apoptosis showed that the higher cell numbers in the scaffolds cultured under dynamic conditions can be explained by increased cell proliferation but not by decreased apoptosis. Glucose consumption and lactate formation by the cells showed that cell metabolism was more aerobic under dynamic compared to static conditions. Lining of the dynamically cultured constructs with a luminal monolayer of endothelial cells might result in vessels suitable for in vivo applications.


Assuntos
Reatores Biológicos , Prótese Vascular , Engenharia Tecidual , Materiais Biocompatíveis , Fenômenos Biomecânicos , Artérias Carótidas/anatomia & histologia , Artérias Carótidas/fisiologia , Células Cultivadas , Colágeno Tipo I/genética , Reagentes de Ligações Cruzadas , Ciclina E/genética , Elastina/genética , Proteínas de Ligação ao GTP , Expressão Gênica , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Proteína 2 Glutamina gama-Glutamiltransferase , Fluxo Pulsátil , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Transglutaminases/genética
13.
Neurosci Lett ; 396(1): 67-72, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16330147

RESUMO

The progressive degenerative process associated with sporadic Parkinson's disease (sPD) is characterized by formation of alpha-synuclein-containing inclusion bodies in a few types of projection neurons in both the enteric and central nervous systems (ENS and CNS). In the brain, the process apparently begins in the brainstem (dorsal motor nucleus of the vagal nerve) and advances through susceptible regions of the basal mid-and forebrain until it reaches the cerebral cortex. Anatomically, all of the vulnerable brain regions are closely interconnected. Whether the pathological process begins in the brain or elsewhere in the nervous system, however, is still unknown. We therefore used immunocytochemisty to investigate the gastric myenteric and submucosal plexuses in 150 microm cryosections and 8 microm paraffin sections from five autopsy individuals, whose brains were also staged for Parkinson-associated synucleinopathy. alpha-synuclein immunoreactive inclusions were found in neurons of the submucosal Meissner plexus, whose axons project into the gastric mucosa and terminate in direct proximity to fundic glands. These elements could provide the first link in an uninterrupted series of susceptible neurons that extend from the enteric to the central nervous system. The existence of such an unbroken neuronal chain lends support to the hypothesis that a putative environmental pathogen capable of passing the gastric epithelial lining might induce alpha-synuclein misfolding and aggregation in specific cell types of the submucosal plexus and reach the brain via a consecutive series of projection neurons.


Assuntos
Corpos de Inclusão/patologia , Plexo Mientérico/fisiopatologia , Neurônios/patologia , Doença de Parkinson/fisiopatologia , Plexo Submucoso/fisiopatologia , alfa-Sinucleína/metabolismo , Idoso , Idoso de 80 Anos ou mais , Transporte Axonal/fisiologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Transmissão de Doença Infecciosa , Feminino , Mucosa Gástrica/inervação , Mucosa Gástrica/fisiopatologia , Humanos , Corpos de Inclusão/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Plexo Mientérico/metabolismo , Plexo Mientérico/patologia , Rede Nervosa/metabolismo , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Vias Neurais/metabolismo , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Neurônios/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Príons/metabolismo , Dobramento de Proteína , Plexo Submucoso/metabolismo , Plexo Submucoso/patologia , Nervo Vago/metabolismo , Nervo Vago/fisiopatologia
14.
J Neuropathol Exp Neurol ; 64(7): 623-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16042314

RESUMO

Sporadic Parkinson disease (sPD) is characterized by alpha-synuclein (alpha-syn) inclusions. The distribution of such inclusions appears to relate to disease progression and severity. We propose and test a simple staging protocol based on the presence of alpha-syn immunoreactivity in 5 paraffin sections that, taken together, contain up to 8 vulnerable brain regions. Six stages of alpha-syn pathology reminiscent for sPD are defined based on the presence or absence of inclusions in the assessed sections. Six observers from 5 different institutions rated 21 cases on the basis of written instructions only. The agreement of the raters was highly significant with a mean error below one stage. Both inter- and intra-rater reliability were also substantial to almost perfect as analyzed by paired comparison between all raters. We propose that the staging procedure for alpha-syn pathology is suitable for application in routine neuropathology and brain banking. Clearly defined stages of alpha-synpathology might aid the comparability between studies and also help to distinguish sPD from other synucleinopathies.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Doença de Parkinson/epidemiologia , Doença de Parkinson/metabolismo , Patologia Clínica/normas , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Variações Dependentes do Observador , Doença de Parkinson/patologia , Reprodutibilidade dos Testes , Sinucleínas , alfa-Sinucleína
15.
Am J Clin Pathol ; 123(5): 690-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15981808

RESUMO

We studied cell cycle-regulating proteins in phyllodes tumor pathogenesis by immunohistochemical analysis for Ki-67, cyclin A, cyclin D1, retinoblastoma protein (pRb), p53, p16INK4A, bcl-2, and p21waf1 in the epithelium and stroma of 40 primary (benign, 21; borderline, 8; malignant, 11) and 7 recurrent tumors of different grades. In most cases, the epithelium showed no altered expression of cell cycle regulators. Stromal overexpression of p16INK4A, p53, cyclin A, pRb, and p21waf1 correlated significantly with tumor grade. The number of altered proteins in stroma increased with higher grade and was accompanied by increased proliferation. Stromal cyclin A expression was the best separating marker between tumor grades. Correlations existed between stromal overexpression of p16NK4A and p21waf1, p16INK4A and p53, and p53 and pRb. No immunostaining differences were detected between primary tumors and recurrences. Four or more altered proteins and p53 expression in the stromal component were independent negative prognosticators for disease-free survival. The stromal component of mammary phyllodes tumors displays an increasing level of cell cycle deregulation with higher tumor grade; the epithelial compartment mostly remains inconspicuous. Several combinations of aberrantly expressed cell cycle proteins seem important in the stromal progression of phyllodes tumors. The number of stromal cell cycle aberrations and stromal p53 expression might predict clinical behavior.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/metabolismo , Ciclo Celular , Tumor Filoide/patologia , Células Estromais/patologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Feminino , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Tumor Filoide/metabolismo , Tumor Filoide/cirurgia , Prognóstico , Células Estromais/metabolismo
16.
J Alzheimers Dis ; 6(5): 469-74, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15505367

RESUMO

alpha-Synuclein is the major constituent of Lewy bodies and Lewy neurites in Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Relatively little is known about the exact mechanism of alpha-synuclein deposition and fibrillization in these alpha-synucleinopathies. In order to better understand the pathogenesis of alpha-synucleinopathies it is important to identify molecules that regulate the fibrillization of alpha-synuclein. Since it has been demonstrated that heparan sulfate proteoglycans (HSPGs) and glycosaminoglycans (GAGs) promote the conversion of non-fibrillar amyloid beta-protein (Abeta) into neurotoxic fibrillar Abeta in Alzheimer's disease, they might also be involved in alpha-synuclein aggregation. It was the aim of our study to examine the distribution pattern of these macromolecules in PD brains and the possible association with Lewy bodies and Lewy neurites. Although HSPGs clearly colocalized with senile plaques, we were unable to identify HSPGs or GAGs in Lewy bodies and Lewy neurites and therefore concluded that it is likely that alpha-synuclein fibrillization and stabilization occurs independently of the presence of HSPGs or GAGs.


Assuntos
Proteoglicanas de Heparan Sulfato/metabolismo , Corpos de Lewy/metabolismo , Neuritos/metabolismo , Doença de Parkinson/metabolismo , Idoso , Anticorpos Monoclonais/imunologia , Encéfalo/imunologia , Encéfalo/metabolismo , Agregação Celular/fisiologia , Feminino , Glicosaminoglicanos/imunologia , Glicosaminoglicanos/metabolismo , Giro do Cíngulo/imunologia , Giro do Cíngulo/metabolismo , Proteoglicanas de Heparan Sulfato/imunologia , Humanos , Imuno-Histoquímica , Corpos de Lewy/imunologia , Masculino , Proteínas do Tecido Nervoso/imunologia , Proteínas do Tecido Nervoso/metabolismo , Neuritos/imunologia , Emaranhados Neurofibrilares/imunologia , Emaranhados Neurofibrilares/metabolismo , Doença de Parkinson/imunologia , Sinucleínas , alfa-Sinucleína
17.
Hum Mol Genet ; 13(16): 1803-13, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15198995

RESUMO

Polyglutamine diseases are characterized by neuronal intranuclear inclusions (NIIs) of expanded polyglutamine proteins, indicating the failure of protein degradation. UBB(+1), an aberrant form of ubiquitin, is a substrate and inhibitor of the proteasome, and was previously reported to accumulate in Alzheimer disease and other tauopathies. Here, we show accumulation of UBB(+1) in the NIIs and the cytoplasm of neurons in Huntington disease and spinocerebellar ataxia type-3, indicating inhibition of the proteasome by polyglutamine proteins in human brain. We found that UBB(+1) not only increased aggregate formation of expanded polyglutamines in neuronally differentiated cell lines, but also had a synergistic effect on apoptotic cell death due to expanded polyglutamine proteins. These findings implicate UBB(+1) as an aggravating factor in polyglutamine-induced neurodegeneration, and clearly identify an important role for the ubiquitin-proteasome system in polyglutamine diseases.


Assuntos
Apoptose/fisiologia , Encéfalo/metabolismo , Transtornos Heredodegenerativos do Sistema Nervoso/metabolismo , Corpos de Inclusão/metabolismo , Peptídeos/metabolismo , Ubiquitina/metabolismo , Western Blotting , Sobrevivência Celular , Clonagem Molecular , DNA Complementar/genética , Imunofluorescência , Transtornos Heredodegenerativos do Sistema Nervoso/fisiopatologia , Humanos , Imuno-Histoquímica , Plasmídeos/genética , Transfecção , Células Tumorais Cultivadas
18.
Acta Neuropathol ; 108(1): 57-64, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15138777

RESUMO

Though cerebral white matter injury is a frequently described phenomenon in aging and dementia, the cause of white matter lesions has not been conclusively determined. Since the lesions are often associated with cerebrovascular risk factors, ischemia emerges as a potential condition for the development of white matter injury. In the present study, we induced experimental cerebral hypoperfusion by permanent, bilateral occlusion of the common carotid arteries of rats (n=6). A sham-operated group served as control (n=6). Thirteen weeks after the onset of occlusion, markers for astrocytes, microglia, and myelin were found to be labeled by means of immunocytochemistry in the corpus callosum, the internal capsule, and the optic tract. The ultrastructural integrity and oligodendrocyte density in the optic tract were investigated by electron microscopy. Quantitative analysis revealed that chronic cerebral hypoperfusion caused mild astrogliosis in the corpus callosum and the internal capsule, while astrocytic disintegration in the optic tract increased by 50%. Further, a ten-fold increase in microglial activation and a nearly doubled oligodendrocyte density were measured in the optic tract of the hypoperfused rats as compared with the controls. Finally, vacuolization and irregular myelin sheaths were observed at the ultrastructural level in the optic tract. In summary, the rat optic tract appears to be particularly vulnerable to ischemia, probably because of the rat brain's angioarchitecture. Since the detected glial changes correspond with those reported in vascular and Alzheimer dementia, this model of cerebral hypoperfusion may serve to characterize the causal relationship between ischemia and white matter damage.


Assuntos
Encéfalo/patologia , Hipóxia-Isquemia Encefálica/patologia , Neuroglia/metabolismo , Análise de Variância , Animais , Encéfalo/ultraestrutura , Antígeno CD11b/metabolismo , Doenças das Artérias Carótidas/complicações , Artéria Carótida Primitiva , Contagem de Células/métodos , Constrição , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Imuno-Histoquímica/métodos , Masculino , Microscopia Eletrônica/métodos , Proteína Básica da Mielina/metabolismo , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Neuroglia/ultraestrutura , Ratos , Ratos Wistar
19.
Biotechnol Appl Biochem ; 39(Pt 2): 141-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15032734

RESUMO

Tissue engineering offers the opportunity to develop vascular scaffolds that mimic the morphology of natural arteries. We have developed a porous three-dimensional scaffold consisting of fibres of collagen and elastin interspersed together. Scaffolds were obtained by freeze-drying a suspension of insoluble type I collagen and insoluble elastin. In order to improve the stability of the obtained matrices, they were cross-linked by two different methods. A water-soluble carbodi-imide, alone or in combination with a diamine, was used for this purpose: zero- or non-zero-length cross-links were obtained. The occurrence of cross-linking was verified by monitoring the thermal behaviour and the free-amino-group contents of the scaffolds before and after cross-linking. Smooth-muscle cells (SMCs) were cultured for different periods of time and their ability to grow and proliferate was investigated. SMCs were isolated from human umbilical and saphenous veins, and the purity of the cultures obtained was verified by staining with a specific monoclonal antibody (mAb). Cultured cells were also identified by mAbs against muscle actin and vimentin. After 14 days, a confluent layer of SMCs was obtained on non-cross-linked scaffolds. As for the cross-linked samples, no differences in cell attachment and proliferation were observed between scaffolds cross-linked using the two different methods. Cells cultured on the scaffolds were identified with an anti-(alpha-smooth-muscle actin) mAb. The orientation of SMCs resembled that of the fibres of collagen and elastin. In this way, it may be possible to develop tubular porous scaffolds resembling the morphological characteristics of native blood vessels.


Assuntos
Técnicas de Cultura de Células/métodos , Colágeno Tipo I/química , Elastina/química , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/fisiologia , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Vasos Sanguíneos/citologia , Vasos Sanguíneos/crescimento & desenvolvimento , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Colágeno Tipo I/ultraestrutura , Elastina/ultraestrutura , Humanos , Teste de Materiais , Músculo Liso Vascular/citologia , Músculo Liso Vascular/crescimento & desenvolvimento , Porosidade , Propriedades de Superfície , Temperatura
20.
Mov Disord ; 19(2): 213-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14978679

RESUMO

The clinical and neuropathological findings in a patient with familial cortical tremor with epilepsy (FCTE) are described. Clinically, the patient showed cortical myoclonus, tremor, and generalized seizures. Pathological investigation showed cerebellar degeneration and somal sprouting and loss of dendritic tree in Purkinje cells. Striking similarities were found in diseases caused by channelopathies such as spinocerebellar ataxia subtype 6.


Assuntos
Córtex Cerebral , Epilepsias Mioclônicas/diagnóstico , Epilepsia Generalizada/diagnóstico , Tremor Essencial/diagnóstico , Degenerações Espinocerebelares/diagnóstico , Idoso , Cerebelo/patologia , Córtex Cerebral/patologia , Dendritos/fisiologia , Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/patologia , Epilepsia Generalizada/genética , Epilepsia Generalizada/patologia , Tremor Essencial/genética , Tremor Essencial/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Regeneração Nervosa/genética , Países Baixos , Linhagem , Células de Purkinje/patologia , Degenerações Espinocerebelares/genética , Degenerações Espinocerebelares/patologia
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