Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intraneuronal filamentous inclusions composed of the microtubule-associated protein tau are a feature of several neurodegenerative diseases (including Alzheimer's disease) known as tauopathies. A pivotal finding was the identification in 1998 of mutations in tau associated with frontotemporal dementia with parkinsonism linked to chromosome 17. This demonstrated that tau dysfunction is sufficient to cause neurodegeneration, and indicated that tau is likely to play a crucial role in the pathogenesis of other tauopathies. However, the mechanism by which tau filamentous lesions form and their role in neurodegeneration remains uncertain. Recent progress in the development of transgenic mouse models of human tauopathy is allowing these questions to be addressed.
Trends Mol Med 2001 Oct
PMID:Analysis of tauopathies with transgenic mice. 1159 22

Multiple system atrophy is an adult onset neurodegenerative disease, featuring parkinsonism, ataxia, and autonomic failure, in any combination. The condition is relentlessly progressive and responds poorly to treatment. Death occurs on average six to seven years after the onset of symptoms. No familial cases of multiple system atrophy have been reported, and no environmental factors have been robustly implicated as aetiological factors. However, analytical epidemiological studies are hampered because the condition is relatively rare. The discovery of the glial cytoplasmic inclusion (GCI) in 1989 helped to define multiple system atrophy as a clinicopathological entity, and drew attention to the prominent, if not primary, role played by the oligodendrocyte in the pathogenesis of the condition. Subsequently, GCIs were shown to be positive for alpha-synuclein, with immunostaining for this protein indicating that white matter pathology was more widespread than had previously been recognised. The presence of alpha-synuclein in GCIs provides a link with Parkinson's disease, dementia with Lewy bodies, and neurodegeneration with brain iron accumulation, type 1 (or Hallervorden-Spatz syndrome), in which alpha-synuclein is also found within Lewy bodies. This has led to the term "synucleinopathy" to embrace this group of conditions. The GCIs of multiple system atrophy contain a range of other cytoskeletal proteins. It is unknown how fibrillogenesis occurs, and whether there is primary oligodendrocytic dysfunction, which then disrupts the neurone/axon as a consequence of the glial pathology, or whether the oligodendrocytic changes merely represent an epiphenomenon. Further research into this devastating condition is urgently needed to improve our understanding of the pathogenesis, and also to produce new treatment approaches.
Mol Pathol 2001 Dec
PMID:Multiple system atrophy: cellular and molecular pathology. 1172 18

The tauopathies, which include Alzheimer's disease (AD) and frontotemporal dementias, are a group of neurodegenerative disorders characterized by filamentous Tau aggregates. That Tau dysfunction can cause neurodegeneration is indicated by pathogenic tau mutations in frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). To investigate how Tau alterations provoke neurodegeneration we generated transgenic mice expressing human Tau with four tubulin-binding repeats (increased by FTDP-17 splice donor mutations) and three FTDP-17 missense mutations: G272V, P301L, and R406W. Ultrastructural analysis of mutant Tau-positive neurons revealed a pretangle appearance, with filaments of Tau and increased numbers of lysosomes displaying aberrant morphology similar to those found in AD. Lysosomal alterations were confirmed by activity analysis of the marker acid phosphatase, which was increased in both transgenic mice and transfected neuroblastoma cells. Our results show that Tau modifications can provoke lysosomal aberrations and suggest that this may be a cause of neurodegeneration in tauopathies.
Mol Cell Neurosci 2001 Dec
PMID:FTDP-17 mutations in tau transgenic mice provoke lysosomal abnormalities and Tau filaments in forebrain. 1174 44

Autosomal dominant myopathy, Paget disease of bone, and dementia constitute a unique disorder (MIM 605382). Here we describe the clinical, biochemical, radiological, and pathological characteristics of 49 affected (23 male, 26 female) individuals from four unrelated United States families. Among these affected individuals 90% have myopathy, 43% have Paget disease of bone, and 37% have premature frontotemporal dementia. EMG shows myopathic changes and muscle biopsy reveals nonspecific myopathic changes or blue-rimmed vacuoles. After candidate loci were excluded, a genome-wide screen in the large Illinois family showed linkage to chromosome 9 (maximum LOD score 3.64 with marker D9S301). Linkage analysis with a high density of chromosome 9 markers generated a maximum two-point LOD score of 9.29 for D9S1791, with a maximum multipoint LOD score of 12.24 between D9S304 and D9S1788. Subsequent evaluation of three additional families demonstrating similar clinical characteristics confirmed this locus, refined the critical region, and further delineated clinical features of this unique disorder. Hence, autosomal dominant inclusion body myopathy (HIBM), Paget disease of bone (PDB), and frontotemporal dementia (FTD) localizes to a 1.08-6.46 cM critical interval on 9p13.3-12 in the region of autosomal recessive IBM2.
Mol Genet Metab 2001 Dec
PMID:Clinical delineation and localization to chromosome 9p13.3-p12 of a unique dominant disorder in four families: hereditary inclusion body myopathy, Paget disease of bone, and frontotemporal dementia. 1174 51

Asiatic acid, a triterpene of Centella asiatica (L.) Urban (Umbelliferae), has been patented as a treatment for dementia and an enhancer of cognition by the Hoechst Aktiengesellschaft (EP 0 383 171 A2). We modified the chemical structure of asiatic acid and obtained 36 derivatives of asiatic acid in an attempt to prepare neuroprotective compounds that were more efficacious than asiatic acid itself. The neuroprotective activities of these derivatives were evaluated using primary cultures of rat cortical neurons insulted with the neurotoxin, glutamate, as an in vitro screening system. Among the semi-synthesized derivatives, three derivatives significantly mitigated the neurotoxicity induced by glutamate in this screening system. The neuroprotective activities of these 3 derivatives appeared to be more powerful than that of asiatic acid itself. These 3 derivatives significantly attenuated decreases in the levels of glutathione, glutathione peroxidase and other enzymes, which participate in the cellular defense mechanisms blunting oxidative stress. Furthermore, they significantly reduced the overproduction of NO induced by glutamate. These results showed that these derivatives of asiatic acid exerted significant neuroprotective effects on cultured cortical cells by their potentiation of the cellular oxidative defense mechanism. Therefore, these agents may prove to be efficacious in protecting neurons from the oxidative damage caused by exposure to excess glutamate.
Res Commun Mol Pathol Pharmacol
PMID:Asiatic acid derivatives protect cultured cortical neurons from glutamate-induced excitotoxicity. 1175 77

The gene of an esterase enzyme, called paraoxonase (PON, EC.3.1.8.1.) is a member of a multigene family that comprises three related genes PON1, PON2, and PON3 with structural homology clustering on the chromosome 7.(1,2) The PON1 activity and the polymorphism of the PON1 and PON2 genes have been found to be associated with risk of cardiovascular diseases such as hypercholesterolaemia, non-insulin-dependent diabetes, coronary heart disease (CHD) and myocardial infaction.(3-8) The importance of cardiovascular risk factors in the pathomechanism of Alzheimer's disease (AD) and vascular dementia (VD)(9-13) prompted us to examine the genetic effect of PON2 gene codon 311 (Cys-->Ser; PON2*S) polymorphism and the relationship between the PON2*S allele and the other dementia risk factor, the apoE polymorphism in these dementias. The PON2*C and PON2*S allele frequencies were similar in both AD (25% and 75%) and VD groups (23% and 77%), respectively, compared with the controls (27% and 73%). The ratio of the PON2*S carriers was significantly higher among the apoE4 allele carrier AD (27%) and VD (25%) groups than in the control (12%). Our results indicate that the PON2*S and apoE4 alleles have interactive effect on the development of the two most common forms of dementias AD and VD, and further support the hypothesis that cardiovascular factors contribute to the development of AD.
Mol Psychiatry 2002
PMID:Codon 311 (Cys --> Ser) polymorphism of paraoxonase-2 gene is associated with apolipoprotein E4 allele in both Alzheimer's and vascular dementias. 1180 56

The results of studies from the Washington University Alzheimer Disease (AD) Research Center and those from other centers and investigators regarding the neuropathologic correlates of normal aging and early-stage AD are reviewed. We conclude that widespread amyloid plaques in the neocortex best distinguishes very early stage AD, including "MCI" stage, and preclinical stages, from healthy brain aging. Other AD lesions, including increased formation of neurofibrillary tangles and neuronal degeneration appear to result from the amyloid-initiated pathologic process, although they may have a more immediate effect on expression and severity of dementia. These data provide strong support for anti-amyloid intervention as a preventive therapy for AD. It is now critical to develop methods to detect preclinical AD during life.
J Mol Neurosci 2001 Oct
PMID:Pathologic correlates of nondemented aging, mild cognitive impairment, and early-stage Alzheimer's disease. 1181 84

Lewy bodies, the characteristic pathological lesion of substantia nigra neurons in Parkinson's disease (PD), are frequently observed to accompany the amyloid plaque and neurofibrillary tangle pathology of Alzheimer's disease (AD). However the typical anatomic distribution of Lewy bodies in AD is distinct from PD. The most common site of occurrence is the amygdala, where Lewy bodies are observed in approximately 60% of both sporadic and familial AD. Other common sites of occurrence include the periamygdaloid and entorhinal cortex, while neocortical and brainstem areas develop Lewy bodies in a lower percentage of cases. In contrast, dementia with Lewy bodies (DLB), defined by widespread neocortical and brainstem Lewy bodies but frequently accompanied by variable levels of AD-type pathology, represents the other end of a spectrum of pathology associated with dementia. The observation of Lewy bodies in familial AD cases suggests that like neurofibrillary tangles, the formation of Lewy bodies can be induced by the pathological state caused by Abeta-amyloid overproduction. The role of Lewy body formation in the dysfunction and degeneration of neurons remains unclear. The protein alpha-synuclein appears to be an important structural component of Lewy bodies, an observation spurred by the discovery of point mutations in the alpha-synuclein gene linked to rare cases of autosomal dominant PD. Further investigation of alpha-synuclein and its relationship to pathological conditions promoting Lewy body formation in AD, PD, and DLB may yield further insight into pathogenesis of these diseases.
J Mol Neurosci 2001 Oct
PMID:Lewy body pathology in Alzheimer's disease. 1181 95

With the arrival of effective symptomatic treatments and the promise of drugs that may delay progression, we now need to identify Alzheimer's disease (AD) at an early stage of the disease. To diagnose AD earlier and more accurately, attention has been directed toward peripheral biochemical markers. This article reviews promising potential cerebrospinal fluid (CSF) biomarkers for AD focussing on their role in clinical diagnosis. In particular, two biochemical markers, CSF total tau (t-tau) protein and the 42 amino acid form of beta-amyloid (Abeta42), perform satisfactorily enough to achieve a role in the clinical diagnostic settings of patients with dementia together with the cumulative information from basic clinical work-up, genetic screening, and brain imaging. These CSF markers are particularly useful to discriminate early or incipient AD from age-associated memory impairment, depression, and some secondary dementias. In order to discriminate AD from other primary dementia disorders, however, more accurate and specific markers are needed. Preliminary evidence strongly suggests that quantification of tau phosphorylated at specific sites in CSF improves early detection, differential diagnosis, and tracking of disease progression in AD.
Mol Neurobiol
PMID:CSF total tau, Abeta42 and phosphorylated tau protein as biomarkers for Alzheimer's disease. 1183 56

Alzheimer's disease (AD) is a common neurodegenerative disease that affects cognitive function in the elderly. Large extracellular beta-amyloid (Abeta) plaques and tau-containing intraneuronal neurofibrillary tangles characterize AD from a histopathologic perspective. However, the severity of dementia in AD is more closely related to the degree of the associated neuronal and synaptic loss. It is not known how neurons die and synapses are lost in AD; the current review summarizes what is known about this issue. Most evidence indicates that amyloid precursor protein (APP) processing is central to the AD process. The Abeta in plaques is a metabolite of the APP that forms when an alternative (beta-secretase and then gamma-secretase) enzymatic pathway is utilized for processing. Mutations of the APP gene lead to AD by influencing APP metabolism. One leading theory is that the Abeta in plaques leads to AD because Abeta is directly toxic to the adjacent neurons. Other theories advance the notion that neuronal death is triggered by intracellular events that occur during APP processing or by extraneuronal preplaque Abeta oligomers. Some investigators speculate that in many cases there is a more general disorder of protein processing in neurons that leads to cell death. In the later models, Abeta plaques are a byproduct of the disease process, rather than the direct cause of neuronal death. A direct correlation between Abeta plaque burden and neuronal (or synaptic) loss should occur in AD if Abeta plaques cause AD through a direct toxic effect. However, histopathologic studies indicate that the correlation between Abeta plaque burden and neuronal (or synaptic) loss is poor. We conclude that APP processing and Abeta formation is important to the AD process, but that neuronal alterations that underlie symptoms of AD are not due exclusively to a direct toxic effect of the Abeta deposits that occur in plaques. A more general problem with protein processing, damage due to the neuron from accumulation of intraneuronal Abeta or extracellular, preplaque Abeta may also be important as underlying factors in the dementia of AD.
Curr Mol Med 2001 Dec
PMID:Beta-amyloid, neuronal death and Alzheimer's disease. 1189 59


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