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

Parkinson's disease (PD) is one of the most common neurodegenerative disorders affecting about 1% of Western populations older than age 50. The pathological hallmark of PD are Lewy bodies, that is, intracytoplasmic inclusion bodies in affected neurons of the substantia nigra. Recently, alpha-synuclein (alpha-SYN) has been identified as the main component of Lewy bodies in sporadic PD, suggesting involvement in neurodegeneration via protein accumulation. The partially overlapping pathology of PD and Alzheimer's disease, as well as striking structural similarities of alpha-SYN and apolipoprotein E, which is a major risk factor for late-onset Alzheimer's disease, prompted us to investigate the influence of different alpha-SYN and apolipoprotein E alleles for developing sporadic PD. We performed association studies in 193 German PD patients and 200 healthy control subjects matched for age, sex, and origin. A polymorphism in the promoter region of the alpha-SYN gene (NACP-Rep1) as well as of the closely linked DNA markers D4S1647 and D4S1628 revealed significant differences in the allelic distributions between PD patients and the control group. Furthermore, the Apo epsilon4 allele but not the Th1/E47 promoter polymorphism of the apolipoprotein E gene was significantly more frequent among early-onset PD patients (age at onset, <50 years) than in late-onset PD. Regarding the combination of the Apo epsilon4 allele and allele 1 of the alpha-SYN promoter polymorphism, a highly significant difference between the group of PD patients and control individuals has been found, suggesting interactions or combined actions of these proteins in the pathogenesis of sporadic PD. PD patients harboring this genotype have a 12.8-fold increased relative risk for developing PD during their lives.
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PMID:Increased susceptibility to sporadic Parkinson's disease by a certain combined alpha-synuclein/apolipoprotein E genotype. 1031 83

Lewy bodies and coarse Lewy neurites are the pathological hallmarks of degenerating neurons in the brains of patients suffering from Parkinson's disease (PD). Recently, the presynaptic protein alpha-synuclein was shown to be a major component of Lewy bodies and Lewy neurites. This study demonstrates for the first time that extensive and thin alpha-synuclein-immunoreactive inclusions are present in the axonal processes of neurons.
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PMID:Extensive axonal Lewy neurites in Parkinson's disease: a novel pathological feature revealed by alpha-synuclein immunocytochemistry. 1032 8

Lewy bodies (LB) and pale bodies (PB), their putative precursors, can be found in a spectrum of diseases characterized by parkinsonism and/or dementia. Furthermore, LB are occasionally observed in some other neurodegenerative diseases and in normal aging. Classical LB are typically found in the brain stem, especially in the substantia nigra, where these inclusions are associated with neuronal loss and clinical signs of idiopathic Parkinson's disease (PD). The so-called cortical LB occur in the cerebral cortex, amygdala and claustrum with little or no neuronal loss and are clinically associated with dementia in dementia with LB (DLB). We describe a patient without apparent clinical signs of parkinsonism and/or dementia, whose brain contained numerous classical-like LB, pale inclusions with features of PB and transitions between these two. These inclusions had similar immunohistological (ubiquitin positive; neurofilament positive; tau negative) and ultrastructural features as the LB in PD and DLB except for the lack of immunoreactivity for alpha-synuclein. The pons and cerebral cortex showed the highest number of LB, up to 165/1.76 mm2. These numbers were contrasted by the lack of obvious neuronal loss or gliosis. The absence of alpha-synuclein reactivity in the LB in this symptomless patient corroborates the hypothesis that alpha-synuclein accumulation in LB is an important step in neurodegeneration in PD and DLB, but tones down the role of alpha-synuclein in LB formation in general. This patient seems to represent a new variant in the spectrum of diseases associated with LB.
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PMID:Numerous and widespread alpha-synuclein-negative Lewy bodies in an asymptomatic patient. 1033 93

Mutations in the human alpha-synuclein gene have been identified in several families of European descent with early-onset Parkinson's disease (PD). We sequenced the complete alpha-synuclein cDNA from substantia nigra and cortex from nine patients with PD and eight control subjects. No mutations were found. We then analyzed alpha-synuclein mRNA levels using a ribonuclease protection assay. Two major protected bands of alpha-synuclein mRNA, possibly representing two splice variants of the gene, were observed. Alpha-synuclein mRNA was significantly diminished in the substantia nigra of patients with PD compared with control subjects but not in the cortex. Our findings suggest that decreased synuclein mRNA may be an early alteration in the SN in PD, and imply that decreased levels of the protein may play a role in the pathogenesis of sporadic cases of the disease.
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PMID:Alpha-synuclein expression in substantia nigra and cortex in Parkinson's disease. 1034 63

Here we review familial Parkinson's disease from clinical, as well as molecular genetic aspects. To date, two genes responsible for familial Parkinson's disease have been identified: one is the alpha-synuclein gene located in the long arm of chromosome 4, and the other is the parkin gene located in the long arm of chromosome 6. The mode of inheritance of the former is autosomal dominant and clinical features consist of levodopa-responsive parkinsonism; the age of onset is younger than that of the sporadic cases (in their 40s), and the progression is faster (average disease duration approximately nine years). The latter form is transmitted as an autosomal recessive, and clinical features consist of early onset (in their 20s), levodopa-responsive parkinsonism, and a slow progression of the disease. In addition, the tau gene has been shown to be the disease gene for familial frontotemporal dementia and parkinsonism linked to chromosome 17. There are many other clinical phenotypes of familial Parkinson's disease among which three forms have been mapped to certain chromosome loci: one is in the short arm of chromosome 2, the two other forms are in the different loci of the short arm of chromosome 4. All of them are transmitted as autosomal dominant traits manifesting levodopa responsive parkinsonism. There still exists however, other clinical phenotypes of chromosome loci which are not known. Molecular cloning of these familial Parkinson's disease genes and the elucidation of the functions of the proteins encoded will certainly contribute greatly to the investigation of the etiology and pathogenesis of more common sporadic form of Parkinson's disease.
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PMID:Genetics of Parkinson's disease. 1034 6

alpha-Synuclein is a component of the abnormal protein depositions in senile plaques and Lewy bodies of Alzheimer's disease (AD) and Parkinson's disease respectively. The protein was suggested to provide a possible nucleation centre for plaque formation in AD via selective interaction with amyloid beta/A4 protein (Abeta). We have shown previously that alpha-synuclein has experienced self-oligomerization when Abeta25-35 was present in an orientation-specific manner in the sequence. Here we examine this biochemically specific self-oligomerization with the use of various metals. Strikingly, copper(II) was the most effective metal ion affecting alpha-synuclein to form self-oligomers in the presence of coupling reagents such as dicyclohexylcarbodi-imide or N-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline. The size distribution of the oligomers indicated that monomeric alpha-synuclein was oligomerized sequentially. The copper-induced oligomerization was shown to be suppressed as the acidic C-terminus of alpha-synuclein was truncated by treatment with endoproteinase Asp-N. In contrast, the Abeta25-35-induced oligomerizations of the intact and truncated forms of alpha-synuclein were not affected. This clearly indicated that the copper-induced oligomerization was dependent on the acidic C-terminal region and that its underlying biochemical mechanism was distinct from that of the Abeta25-35-induced oligomerization. Although the physiological or pathological relevance of the oligomerization remains currently elusive, the common outcome of alpha-synuclein on treatment with copper or Abeta25-35 might be useful in understanding neurodegenerative disorders in molecular terms. In addition, abnormal copper homoeostasis could be considered as one of the risk factors for the development of disorders such as AD or Parkinson's disease.
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PMID:Copper(II)-induced self-oligomerization of alpha-synuclein. 1035 69

The pathogenesis of idiopathic Parkinson's disease (PD) is not known, but is thought to be multifactorial, deriving from environmental factors acting on genetically predisposed individuals with aging. Association studies of DNA polymorphisms are able to detect a genetic background predisposing to PD. Mechanisms as oxidative stress, xenobiotica toxicity and altered dopamine metabolism might lead to a selective cell death of most vulnerable nerve cells and represent the primary subject to be studied by DNA analysis. Furthermore, protein aggregation is likely to be a major cause for the disease. Recently it has been shown that alpha-synuclein is accumulated in Lewy bodies of sporadic PD and mutated in some rare families with an autosomal dominant trait of the disease (ADPD). The identification of further genes responsible for PD will subsequently lead to first insights into the pathogenesis of one of the most common neurodegenerative disorders in humans.
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PMID:Parkinson's disease--a multifactorial neurodegenerative disorder. 1037 Sep 6

Parkinson's disease (PD) is a neurodegenerative disorder that is pathologically characterized by the presence of intracytoplasmic Lewy bodies, the major components of which are filaments consisting of alpha-synuclein. Two recently identified point mutations in alpha-synuclein are the only known genetic causes of PD. alpha-Synuclein fibrils similar to the Lewy body filaments can be formed in vitro, and we have shown recently that both PD-linked mutations accelerate their formation. This study addresses the mechanism of alpha-synuclein aggregation: we show that (i) it is a nucleation-dependent process that can be seeded by aggregated alpha-synuclein functioning as nuclei, (ii) this fibril growth follows first-order kinetics with respect to alpha-synuclein concentration, and (iii) mutant alpha-synuclein can seed the aggregation of wild type alpha-synuclein, which leads us to predict that the Lewy bodies of familial PD patients with alpha-synuclein mutations will contain both, the mutant and the wild type protein. Finally (iv), we show that wild type and mutant forms of alpha-synuclein do not differ in their critical concentrations. These results suggest that differences in aggregation kinetics of alpha-synucleins cannot be explained by differences in solubility but are due to different nucleation rates. Consequently, alpha-synuclein nucleation may be the rate-limiting step for the formation of Lewy body alpha-synuclein fibrils in Parkinson's disease.
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PMID:alpha-synuclein fibrillogenesis is nucleation-dependent. Implications for the pathogenesis of Parkinson's disease. 1039 81

alpha-Synuclein has been implicated in the pathophysiology of many neurodegenerative diseases, including Parkinson's disease (PD) and Alzheimer's disease. Mutations in alpha-synuclein cause some cases of familial PD (Polymeropoulos et al., 1997; Kruger et al., 1998). In addition, many neurodegenerative diseases show accumulation of alpha-synuclein in dystrophic neurites and in Lewy bodies (Spillantini et al., 1998). Here, we show that alpha-synuclein shares physical and functional homology with 14-3-3 proteins, which are a family of ubiquitous cytoplasmic chaperones. Regions of alpha-synuclein and 14-3-3 proteins share over 40% homology. In addition, alpha-synuclein binds to 14-3-3 proteins, as well as some proteins known to associate with 14-3-3, including protein kinase C, BAD, and extracellular regulated kinase, but not Raf-1. We also show that overexpression of alpha-synuclein inhibits protein kinase C activity. The association of alpha-synuclein with BAD and inhibition of protein kinase C suggests that increased expression of alpha-synuclein could be harmful. Consistent with this hypothesis, we observed that overexpression of wild-type alpha-synuclein is toxic, and overexpression of alpha-synuclein containing the A53T or A30P mutations exhibits even greater toxicity. The activity and binding profile of alpha-synuclein suggests that it might act as a protein chaperone and that accumulation of alpha-synuclein could contribute to cell death in neurodegenerative diseases.
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PMID:alpha-Synuclein shares physical and functional homology with 14-3-3 proteins. 1040 19

We report an 80-year-old Japanese woman who presented levodopa-responsible parkinsonism followed by progressive dementia. She was well until her 61 years of age (in 1978) when she noted onset of resting tremor in her right hand followed by tremor in her right leg. She was treated with levodopa and trihexyphenidyl with good response, however, later on, she suffered from gait disturbance. In 1985, she had an episode of cardio-pulmonary arrest from which she was resuscitated, however, she started to show hypermetamorphosis, memory defect, and aggressive behaviors. She also developed motor fluctuations and dyskinesias from levodopa. She was admitted to our service in 1986; she showed rather typical parkinsonism and mild dementia. She received left Vim thalamotomy in the same year. Her dyskinesias improved, however, her gait disturbance became progressively worse. In 1995, she was admitted to our service again; she showed marked dementia and advanced parkinsonism; she was unable to walk unsupported. She became bedridden in 1996 and gastrostomy was placed. She was transferred to Zushi Aoki Hospital. Her dementia became progressively worse, and she was in the akinetic and mute state. She expired on April 22, 1998. She was discussed in a neurological CPC. The chief discussant arrived at a conclusion that the patient had Parkinson's disease with complication by Alzheimer's disease in her later clinical course. The diagnoses of participants were divided among Parkinson's disease with dementia, Parkinson's disease and Alzheimer's disease, and diffuse Lewy body disease. Postmortem examination revealed marked neuronal loss in the substantia nigra and the locus coeruleus. Lewy bodies were found in the substantia nigra. In addition, rather many Lewy bodies of cortical type were seen in the cingulate gylus, inferior temporal gylus, and in the amygdaloid nucleus. These Lewy bodies were positive for alpha-synuclein. Also, tau-positive intra-neuronal tangles were seen in the hippocampus and in the substantia nigra. The Meynert nucleus showed marked neuronal loss. Pathologic findings were consistent with the diagnosis of diffuse Lewy body disease.
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PMID:[An 80-year-old woman with parkinsonism and progressive dementia]. 1042 59


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