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Disease
Symptom
Drug
Enzyme
Compound
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Query: UNIPROT:P10636 (
tau protein
)
5,110
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
To evaluate glial lesions in cases of dementia with Lewy bodies (DLB), we studied the brains of four patients with DLB. Astrocytic star-like inclusions, which resembled tufted astrocytic fibrillary tangles in shape, were found in the cortex of two of these cases. In addition, coiled bodies were found in the white matter of the cerebrum in two cases. The astrocytic star-like inclusions were immunohistochemically negative for
tau protein
, ubiquitin and
alpha-synuclein
. The coiled bodies were immunohistochemically negative for
tau protein
but immunopositive for ubiquitin and
alpha-synuclein
. These results suggest that in DLB a primary degenerative process takes place in both glial cells and neurons.
...
PMID:Tau-negative astrocytic star-like inclusions and coiled bodies in dementia with Lewy bodies. 1104 67
The most common degenerative diseases of the human brain are characterized by the presence of abnormal filamentous inclusions in affected nerve cells and glial cells. These diseases can be grouped into two classes, based on the identity of the major proteinaceous components of the filamentous assemblies. The filaments are made of either the
microtubule-associated protein tau
or the protein
alpha-synuclein
. Importantly, the discovery of mutations in the tau gene in familial forms of frontotemporal dementia and of mutations in the
alpha-synuclein
gene in familial forms of Parkinson's disease has established that dysfunction of
tau protein
and
alpha-synuclein
can cause neurodegeneration.
...
PMID:From genetics to pathology: tau and alpha-synuclein assemblies in neurodegenerative diseases. 1126 Aug 2
Intracellular filamentous inclusions made of either the
microtubule-associated protein tau
or the protein
alpha-synuclein
define the majority of cases of neurodegenerative disease. Mutations in the tau gene in familial forms of frontotemporal dementia and in the
alpha-synuclein
gene in familial cases of Parkinson's disease have provided causal links between the dysfunction of these proteins and neurodegeneration. Over the past year, several novel tau gene mutations have been identified and more has been learned about possible mechanisms by which tau gene mutations lead to frontotemporal dementia. Experimental animal models have provided a link between tau filament formation and nerve cell degeneration. Along similar lines, animal models have been produced that result in the formation of
alpha-synuclein
filaments and the degeneration of dopaminergic nerve cells. Building on previous work, synthetic
alpha-synuclein
filaments have been shown to exhibit the characteristics of amyloid.
...
PMID:The significance of tau and alpha-synuclein inclusions in neurodegenerative diseases. 1137 73
Multiple factors have been hypothesized over the last century to be causative or contributory for Parkinson's disease. Hereditary factors have recently emerged as a major focus of Parkinson's disease research. Until recently most of the research on the etiology of Parkinson's disease concentrated on environmental factors, and the possibility that genetic factors contribute significantly to the pathogenesis of Parkinson's disease has been neglected. However, it has become increasingly apparent that even in sporadic cases, the disease most likely reflects a combination of genetic susceptibility and an unknown environmental insult. Moreover, the identification of genes and proteins that may cause hereditary parkinsonism substantially contributes to our ability to understand the pathogenesis of Parkinson's disease and may help in the early identification of the disease and its treatment. The discovery of
alpha-synuclein
mutations in families with autosomal dominant Parkinson's disease sheds light on its role in sporadic Parkinson's disease. It seems that this protein tends to aggregate when the cellular milieu is altered [14-16]. The question as to the exact changes that cause its deposition remains open. One of the major possibilities is oxidative stress [16]. The role of these aggregates in neuronal cell death is also still unclear. Transgenic mice expressing wild-type human
alpha-synuclein
developed progressive accumulation of
alpha-synuclein
and ubiquitin-immunoreactive inclusions in neurons in the neocortex, hippocampus and the substantia nigra. These alterations were associated with loss of dopaminergic terminals and motor impairments [24]. This finding suggests that accumulation of
alpha-synuclein
may play a causal role in sporadic Parkinson's disease as well. The parkin protein seems to be a crucial survival factor for nigral neurons [15]. The parkin protein is related to the ubiquitin pathway, which is important in the elimination of damaged proteins. Ubiquitin-mediated degradation of proteins plays a central role in the control of numerous processes, including signal transduction, receptor and transcriptional regulations, programmed cell death, and breakdown of abnormal proteins that may interfere with normal cell functions. Further studies on the function of Parkin protein and its relation to the ubiquitin pathway could elucidate at least one of the molecular mechanisms of nigral neuronal death. A mutation in the ubiquitin carboxy-teminal hydrolase L1 gene also implies the importance of the ubiquitin pathway in Parkinson's disease. Abnormal
tau protein
was found to be the cause of familial frontotemporal dementia and parkinsonism. It tends to form filamentous structures, which may lead to neuronal death. Elucidation of the molecular mechanism of neuronal death in this disease may contribute to our understanding of sporadic diseases with tau accumulation, such as corticobasal degeneration, progressive supranuclear palsy, Pick's disease, Alzheimer's disease and possibly also the pathogenesis of Parkinson's disease. Other genetic loci have been identified by linkage analysis of patients with familial parkinsonism. These loci conceal other genes and proteins that may be pivotal factors in the pathogenesis of Parkinson's disease. The discovery of genetic mutations in patients with parkinsonism may offer us new insights into the understanding of the pathways leading to neuronal death and development of Parkinson's disease. It may also help in the early identification of susceptible people to this disease and possibly in developing new treatment strategies.
...
PMID:Heredity in Parkinson's disease: new findings. 1143 38
We examined the immunoreactivity of ubiquitin-binding protein p62 and its association with ubiquitin (Ub),
alpha-synuclein
, and paired helical filament (PHF)-tau in the affected brain areas of human tauopathies and synucleinopathies. Ubiquitin-binding protein p62 is a widely expressed protein that can bind to Ub noncovalently and is involved in several signalling pathways, making p62 a candidate regulator of Ub-mediated proteolysis. We show that p62 immunoreactivity co-localizes with neuronal and glial Ub-containing inclusions in Alzheimer's disease, Pick's disease, dementia with Lewy bodies, Parkinson's disease, and multiple system atrophy. This is the first demonstration of a common protein component, apart from Ub, that is present in both
PHF-tau
and
alpha-synuclein
inclusions. In both tauo- and synucleinopathies, the staining patterns for p62 and Ub were markedly similar, suggesting that a common mechanism which requires interaction of p62 and Ub contributes to the formation of
PHF-tau
and
alpha-synuclein
inclusions.
...
PMID:Ubiquitin-binding protein p62 is present in neuronal and glial inclusions in human tauopathies and synucleinopathies. 1144 12
Hereditary frontotemporal dementia (FTD) is an autosomal dominant neurodegenerative disorder that is associated with mutations in the tau gene and with the pathological accumulation of hyperphosphorylated
tau protein
in affected brain cells in about a quarter of cases. However, most FTD families have no demonstrable tau mutations. Here we describe the clinical and neuropathological features of a large family with hereditary FTD. Genetic analysis showed strong evidence for linkage to chromosome 17q21-22 (maximum lod score 3.46, theta = 0 for marker D17S950), but mutations in the tau gene were not found. Clinical symptoms, neuropsychological deficits and neuroimaging findings of affected family members were similar to sporadic and tau-related FTD. The mean age at onset was 61.2 years, with loss of initiative and decreased spontaneous speech as the most prominent presenting symptoms. Pathological examination of the brains of two affected family members showed non-specific neuronal degeneration with dense cytoplasmic ubiquitin-positive inclusions in neurones of the second layer of the frontotemporal cortex and dentate gyrus of the hippocampus. In a number of neurones these inclusions appeared to be located inside the nucleus, although due to the small number of these inclusions this localization could not be confirmed by electron microscopy. The inclusions were not stained by tau,
alpha-synuclein
or polyglutamine antibodies. Biochemical analysis of soluble tau did not reveal abnormalities in tau isoform distribution and analysis of mRNA showed the presence of both three- and four-repeat transcripts. This is the first report of ubiquitin-positive, tau-negative inclusions in an FTD family with significant linkage to chromosome 17q21-22. Further characterization of the ubiquitin-positive inclusions may clarify the neurodegenerative pathways involved in this subtype of FTD.
...
PMID:Familial frontotemporal dementia with ubiquitin-positive inclusions is linked to chromosome 17q21-22. 1157 Dec 13
Argyrophilic glial inclusions, which are immunohistochemically positive for
alpha-synuclein
but negative for
tau protein
, were examined in the brain of Parkinson's disease (PD) patients. Autopsied brains of 10 individuals who died from PD, of two incidental Lewy body disease cases and of five age-matched individuals whose deaths were caused by non-neurological diseases were studied, histopathologically, by Gallyas-Braak staining and, immunohistochemically, with anti-
alpha-synuclein
antibody, anti-ubiquitin, and anti-tyrosine hydroxylase. All postmortem PD brains showed a significant number of argyrophilic glial inclusions, but no glial inclusions were found in control brains. The inclusions were found not only in the regions showing neuronal loss and gliosis, such as the substantia nigra, locus ceruleus and dorsal vagal nucleus, but also in regions without neuronal loss and gliosis, such as the cerebral cortex, cerebral white matter, striatum, globus pallidus, thalamus, cerebellum and spinal cord. The distribution and density of glial inclusions in PD brains varied from case to case but, in the cerebral cortex, the number of glial inclusions were fairly well correlated with the number of Lewy bodies. The distribution pattern of glial inclusions also showed a striking resemblance to that of catecholaminergic neurones and fibres. The abnormal accumulation of
alpha-synuclein
in glial cells was more widespread than neurone loss, and appears to be an important pathological feature of PD.
...
PMID:Widespread occurrence of argyrophilic glial inclusions in Parkinson's disease. 1167 88
The calcium-activated protease calpain cleaves a variety of biologically important proteins and serves, therefore, as a key regulator of many cellular functions. Activation of both main isoforms, calpain 1 and calpain 2, was demonstrated previously in Alzheimer's disease. In this report, antibodies specifically recognizing the active form of calpain 2 were used to investigate calpain 2 activation in a broad range of neurodegenerative diseases, utilizing multiple-label confocal immunofluorescence imaging. With rare exceptions, the active form of calpain 2 was found in colocalization with hyperphosphorylated
tau protein
. Aggregates of mutated huntingtin,
alpha-synuclein
, or unidentified protein in motor neuron disease type of frontotemporal dementia were always negative. These findings indicate that calpain 2 activation is not a general response to protein aggregation. In tauopathies, more pathological inclusions were labeled for hyperphosphorylated tau than for activated calpain 2. The extent of colocalization varied in both a disease-specific and cell-type specific manner. The active form of calpain 2 was detected in 50-75% of tau neurofibrillary pathology in Alzheimer's disease, Alzheimer neurofibrillary changes and Down's syndrome, as well as in the accompanying Alzheimer-type tau pathology in diffuse Lewy bodies disease, progressive supranuclear palsy, and corticobasal degeneration. For glial cells, only 10-25% of tuft-shaped astrocytes, glial plaques, or coiled bodies contained activated calpain 2. The majority of Pick bodies were negative. The association of calpain 2 activation with hyperphosphorylated tau might be the result of an attempt by the calpain proteolytic system to degrade the
tau protein
aggregates. Alternatively, calpain 2 could be directly involved in tau hyperphosphorylation by modulating protein kinase activities. Overall, these results provide evidence of the important role of the calpain proteolytic system in the pathogenesis of neurodegenerative diseases with tau neurofibrillary pathology.
...
PMID:Calpain activation in neurodegenerative diseases: confocal immunofluorescence study with antibodies specifically recognizing the active form of calpain 2. 1207 Jun 70
Age-related changes in hormone levels are determinants of a variety of human diseases. Insulin is known to affect numerous brain functions including cognition and memory, and several clinical studies have established links between Alzheimer's disease (AD), insulin resistance and diabetes mellitus. These are reinforced by biological studies that reveal the effects of insulin on the molecular and cellular mechanisms that underlie the pathology of AD. For example, insulin regulates phosphorylation of
tau protein
, which underlies neurofibrillary lesions in the brains of AD patients. Insulin also affects the metabolism of beta-amyloid, the main constituent of
AD amyloid
pathology. Here, we discuss clinical and biological data that highlight potential targets for therapeutic intervention.
...
PMID:Does insulin dysfunction play a role in Alzheimer's disease? 1208 35
Neurodegenerative diseases have long been considered to be poorly defined, misunderstood, and inadequately treated. In recent years, research on Alzheimer's disease has led to numerous advances that have improved our understanding of this form of dementia and also of the entire category of neurodegenerative diseases. It now appears that numerous neurodegenerative diseases of the central nervous system correspond to the aggregation of specific proteins: beta-amyloid in Alzheimer disease,
tau protein
in Alzheimer disease, fronto-temporal dementia, progressive supranuclear palsy and corticobasal degeneration,
alpha-synuclein
in Parkinson disease and Lewy body dementia, PrP protein in prion diseases, SOD in amyotrophic lateral sclerosis, polyglutamine expansions in Huntington's disease and other diseases, etc. It is remarkable that in all these cases mutations have been identified for genes coding for these proteins and able to cause the disease and, moreover, that the introduction of the corresponding gene into transgenic mice (or other transgenic animals) has made it possible to create animal models of these conditions. This suggests that the proteins in question play a determinative role in the pathogenesis of these diseases and are not simply consequences of it. Neurodegenerative diseases are proteinopathies. But they are also networkopathies because the neuronal proteins are organized in functional networks. We must also note that all these diseases are associated with the process of aging, for they do not appear in the young. This fact suggests that the anomaly (genetic or otherwise) concerning a given protein does not suffice by itself to induce the disease process. Many observations suggest that the additional event involved, common to all neurodegenerative conditions, may be the intervention of free radicals. We thus propose here the theory that the diversity of neurodegenerative diseases is explained by the combination of two pathogenic events: one specific and associated with the aggregation of a particular protein in the nervous system, the other, non-specific and associated with aging and with the production and harmful actions of free radicals. This unified interpretation leads directly to treatment hypotheses: the development of drugs capable either of inhibiting the production or aggregation of proteins specifically implicated in diverse diseases (or promoting their elimination) or of inhibiting the production or action of free radicals in the nervous system. The former should target one of these various diseases, and the latter should act on a wide range of diseases. The two approaches may conceivably be combined.
...
PMID:[Proteins and mutations: a new vision (molecular) of neurodegenerative diseases]. 1213 39
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