Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lewy Body Variant (LBV) patients present as Alzheimer's disease (AD) clinically; about two-thirds also have mild extrapyramidal features. At autopsy, neocortical and brain stem Lewy bodies are present in addition to changes diagnostic of AD. We have found that the Apolipoprotein E4 allele is a major genetic risk factor for LBV as it is for "pure AD," in contrast to subjects with diffuse Lewy body disease or Parkinson's disease. This genetic evidence supports the concept that LBV--the second most common neurodegenerative form of dementia--is a phenotypic variant of AD.
 ...
PMID:Genetic evidence that the Lewy body variant is indeed a phenotypic variant of Alzheimer's disease. 854 53

The neuropathology of parkinsonism is reviewed as it occurs in primary (idiopathic) and secondary extrapyramidal syndromes. Present understanding of the significance of Lewy bodies in Parkinson's disease, diffuse Lewy body disease, and Lewy body variant of Alzheimer's disease is emphasized. The neuropathology produced by a variety of secondary causes is also considered to demonstrate the diverse lesions that can result in parkinsonism.
 ...
PMID:The neuropathology of parkinsonism: an overview. 854 58

Lewy bodies (LBs) are intracytoplasmic neuronal inclusions sometimes found in the brain stem, diencephalon, basal ganglia, and cerebral cortex. Cases designated as diffuse Lewy body disease (DLBD) demonstrate widespread cortical and subcortical Lewy body formation. The fact that DLBD is possibly the second most common cause of dementia after Alzheimer's disease is not generally recognized. We hope to emphasize the importance of this common neurodegenerative disorder by reviewing the literature and our own experience with DLBD. The English-language literature dealing with the clinical and pathological features of DLBD was reviewed. Pathological material from the Canadian Brain Tissue Bank, Toronto, Ontario, was reviewed over a 2-year period from 1991 through 1993. Prominent LB pathology may occur in isolation or mixed with pathological changes seen in Alzheimer's disease. Lewy body diseases include Parkinson's disease that presents with a classic movement disorder and sometimes dementia, and DLBD where LBs occur in a widespread distribution in the cortex in addition to the usual subcortical sites. Diffuse LB disease usually presents with a neurobehavioral syndrome that may include hallucinations, delusions, and psychosis; all patients eventually become demented. A day-to-day fluctuating mental state may be an important distinguishing clinical feature. Parkinsonism may follow the psychiatric disturbance although occasionally it is a presenting feature. Serious life- threatening side effects may occur with the use of standard neuroleptics. The variable clinical features and additional presence of Alzheimer-type pathological changes in many cases of DLBD has led to a confusing and inconsistent classification of LB disease and, together with little awareness of its existence, its misdiagnosis. Although DLBD may be the second most common cause of dementia, the terminology and classification of LB disorders and their relationship to Alzheimer's disease remain sources of intense debate. Further research is needed to resolve these issues and to provide insight into the pathogenesis of LB formation and accompanying neuronal degeneration.
 ...
PMID:Lewy body disease and dementia. A review. 860 54

Lewy bodies (LBs) are the pathological hallmarks of degenerating neurons in the brains of patients with Parkinson's disease and diffuse Lewy body disease. We developed a novel purification procedure for LBs using sucrose density separation followed by fluorescence-activated particle sorting, and we raised > 15 monoclonal antibodies to LBs purified from diffuse Lewy body disease brains. The monoclonal antibody that stained the largest number of LBs most intensely did not recognize ubiquitin in free or monoubiquitinated forms nor the ubiquitin conjugating enzymes, but it did react with polyubiquitin chains as well as with high molecular weight polyubiquitinated LB-derived proteins. Thus, these results suggest that LBs contain polyubiquitin chains. Although polyubiquitination of LB proteins may trigger ubiquitin-proteasome proteolytic pathways, the incomplete activation of these pathways could play a mechanistic role in the formation of LBs in neurodegenerative diseases.
 ...
PMID:Purification and characterization of Lewy bodies from the brains of patients with diffuse Lewy body disease. 862 21

The levels of the neuropeptides Met- and Leu-enkephalin (MET-ENK, LEU-ENK), substance P and neurotensin were measured by a combined high performance liquid chromatography/radioimmunoassay (HPLC/RIA) method in postmortem samples of basal ganglia from Parkinson's disease patients, incidental Lewy body disease patients (pre-symptomatic Parkinson's disease) and matched controls. Dopamine (DA) levels were reduced in the caudate nucleus and putamen in Parkinson's disease, but unaltered in incidental Lewy body disease. The levels of MET-ENK were reduced in the caudate nucleus, putamen and substantia nigra in Parkinson's disease. Met-enkephalin levels were reduced in the caudate nucleus and in the putamen in incidental Lewy body disease. Leu-enkephalin levels were decreased in the putamen and were undetectable in the substantia nigra in Parkinson's disease. Leu-enkephalin levels were unchanged in incidental Lewy body disease, although there was a tendency to a reduction in putamen. Substance P levels were reduced in the putamen in Parkinson's disease. No significant changes in substance P content were observed in incidental Lewy body disease. Neurotensin levels were increased in the substantia nigra in Parkinson's disease. Neurotensin levels in incidental Lewy body disease were not altered significantly, but tended to parallel the changes in Parkinson's disease. The changes in basal ganglia peptide levels in incidental Lewy body disease generally followed a trend similar to those seen in Parkinson's disease, but were less marked. This suggests that they are an integral part of the pathology of the illness and not secondary to DA neuronal loss or a consequence of prolonged drug therapy.
 ...
PMID:Alterations in peptide levels in Parkinson's disease and incidental Lewy body disease. 867 94

The underlying mechanism of cell death in substantia nigra of Parkinson's disease patients remains unknown. Biochemical changes occurring in substantia nigra in Parkinson's disease (increased iron levels, inhibition of complex I activity and decreased reduced glutathione levels; GSH) suggest that oxidative stress and free radical species may be involved. In particular, a decrease in GSH levels may be an early component of the process, since this also occurs in incidental Lewy body disease (presymptomatic Parkinson's disease). GSH is lost only from the substantia nigra in Parkinson's disease and this does not occur in other neurodegenerative disorders of the basal ganglia. GSH loss appears to be global throughout the substantia nigra and not localized to either the glia or neuronal elements. The activity of enzymes involved in the glutathione cycle are normal with the exception of gamma-glutamyltranspeptidase, the activity of which is increased. This could result in increased removal and degradation of glutathione from cells. Depletion of GSH in rat using L-buthionine-[S, R]-sulfoxamine (BSO) potentiates 6-hydroxydopamine (6-OHDA) toxicity but does not in itself produce degeneration of the nigrostriatal pathway. Oxidative stress may be a potentially important factor in the degeneration of the substantia nigra in Parkinson's disease and warrants further investigation into its role in this process.
 ...
PMID:Oxidative stress and Parkinson's disease. 868 21

Neuronal death associated with plaque and tangle formation characteristic of Alzheimer's disease (AD) may result from an underlying defect of intracellular protein catabolism. In an attempt to identify the proteolytic enzyme types responsible for aberrant protein processing, we have composed the levels of activity of proline endopeptidase in brain tissue samples (grey/white matter) from frontal, parietal, temporal and occipital lobes, from normal control cases, and cases with AD, Lewy body dementia (LBD), Parkinson's disease (PD) and Huntington's disease (HD). The activity of proline endopeptidase was significantly reduced in AD to approximately 65% of that of corresponding control tissue-this is of note since previous biochemical analyses have in general failed to detect altered activity of other protease types in AD tissues. However, this relatively selective reduction in proline endopeptidase activity in AD tissue (in terms of protease types investigated) is not specific for disease type, since activity was also reduced (65%-70% of control) in tissue samples from LBD, PD and HD cases. The data suggest that reduction in proline endopeptidase activity may be a characteristic of a generalized process of neurodegeneration. Although the precise cellular function of this enzyme in normal/ pathological tissues remains to be determined, the question arises as to whether pharmacological strategies designed to enhance proline endopeptidase activity in brain tissue may improve patient outcome in the above disorders.
 ...
PMID:Comparison of proline endopeptidase activity in brain tissue from normal cases and cases with Alzheimer's disease, Lewy body dementia, Parkinson's disease and Huntington's disease. 873 97

Amygdalae of patients with Alzheimer's disease (AD), Parkinson's disease, Down's syndrome, diffuse Lewy body disease or a combination of these diseases were probed with antibodies to neurofilament proteins as well as with Lewy body (LB)- and paired helical filament-specific antibodies. The results indicate that the amygdala is severely affected by the accumulation of both neurofibrillary tangles (NFTs) and LBs in most cases of the diseases mentioned above, and that amygdala LBs have a similar epitope composition to that of LBs in the brain stem and cerebral cortex. While large numbers of both LBs and NFTs were seen in different neurons within the amygdala, these two lesions frequently occurred together in the same neurons of the amygdala. These findings are in contrast to other sites that accumulate LBs and NFTs, but rarely both lesions in the same neuron. Thus, amygdala neurons may be selectively vulnerable to developing both LBs and NFTs, and these inclusions may play a role in the massive degeneration of these neurons in AD and LB disorders of the elderly.
 ...
PMID:Convergence of Lewy bodies and neurofibrillary tangles in amygdala neurons of Alzheimer's disease and Lewy body disorders. 874 Feb 27

Ubiquitin-positive Lewy neurites and Lewy bodies are found in idiopathic Parkinson's disease (PD) and diffuse Lewy body disease (DLBD). We found that, in three patients with PD and one with DLBD, microtubule-associated protein 5 (MAP5) immunostaining was consistently present in both Lewy neurites and Lewy bodies throughout the brainstem and forebrain regions affected in the disease. In contrast, other cytoskeletal markers (neurofilaments and MAP2) could be demonstrated in only a small fraction of Lewy bodies and neurites. Confocal microscopy demonstrated that MAP5 immunolabeling was located around the perimeter of the ubiquitin-positive labeling which occupied the central region of the neurite and Lewy body, with some overlap between MAP5 and ubiquitin staining. In contrast, in those Lewy bodies and neurites immunopositive for phosphorylated and non-phosphorylated neurofilament proteins, the neurofilament labeling was quite peripheral to the ubiquitin staining, with little or no overlap. Our results suggest MAP5 is more closely associated with the ubiquitinated proteins of Lewy bodies and neurites than other cytoskeletal proteins.
 ...
PMID:Microtubule-associated protein 5 is a component of Lewy bodies and Lewy neurites in the brainstem and forebrain regions affected in Parkinson's disease. 877 50

Lewy bodies (LBs)are found throughout the brain stem, limbic and neocortical areas in Parkinson's disease. Lewy bodies are also associated in these areas with dementia and the substrate of 'dementia with Lewy bodies' is thought to include Lewy body pathology in limbic and neocortical areas with or without Alzheimer-type changes. In order to determine whether dementia with Lewy bodies is characterised primarily by cortical or limbic LB pathology, we have measured the density of Lewy bodies, neuritic plaques and neurofibrillary tangles in 12 neocortical, limbic and brain stem sites in 10 patients who were pathologically diagnosed with diffuse Lewy body disease (DLBD) (64.7 +/- 2.7 years). The mean LB density in limbic areas (3.00 +/- 0.61/mm2) was significantly greater than that of neocortical areas (1.13 +/- 0.22/mm2, P < 0.001). The greatest density of LBs was found in the amygdala (4.1 +/- 0.7/mm2) and the lowest in the occipital cortex (0.3 +/- 0.1/mm2). In limbic areas, LB formation positively correlated with neuritic plaque formation (r = 0.51, P < 0.01) but not with neurofibrillary tangle densities. These data indicate that dementia with Lewy bodies is characterised primarily by limbic, and secondly by neocortical, LB pathology. It remains to be determined why limbic areas are selectively vulnerable to LB pathology in dementia with Lewy bodies.
 ...
PMID:Lewy bodies are located preferentially in limbic areas in diffuse Lewy body disease. 883 51


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>