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)

Parkinson's disease is a frequent disorder caused primarily by the loss of dopaminergic neurons of the substantia nigra. Mutations in the PTEN-induced kinase (PINK1) gene, in addition to those in parkin and DJ-1, have been found in families with recessive early-onset Parkinson's disease. We screened for parkin and PINK1 mutations in a panel of 177 autosomal recessive Parkinson's disease families with ages at onset < or =60 years, mostly from Europe. In 7 unrelated families, we identified 10 pathogenic PINK1 mutations (5 missense, 2 nonsense and 3 frameshift deletion mutations), 8 of which were novel. All the mutations were in the homozygous or compound heterozygous states. Interestingly, pseudo-dominant inheritance was observed in a family with two different mutations. The clinical characteristics of 12 PINK1 patients and 114 parkin patients were similar, even for signs such as dystonia at onset and increased reflexes, which were thought to be specific to parkin. In contrast, onset in patients with PINK1 mutations was earlier and increased reflexes were found more frequently than in patients without PINK1 or parkin mutations. These results suggest that PINK1 is the second most frequent causative gene in early-onset Parkinson's disease with a slowly progressive phenotype, indistinguishable from early-onset patients with parkin mutations.
 ...
PMID:Mutational analysis of the PINK1 gene in early-onset parkinsonism in Europe and North Africa. 1640 16

DJ-1 has been reported to have chaperone activity by preventing the aggregation of some proteins, and by structural analogy to Hsp31. The L166P mutation has been linked to a familial early onset form of Parkinson's disease (PD). Since the aggregation of alpha-synuclein is believed to be a critical step in the etiology of PD, we have investigated the interaction of wild-type DJ-1 and its oxidized forms with alpha-synuclein. Native (unoxidized) DJ-1 did not inhibit alpha-synuclein fibrillation, and no evidence for stable interactions between alpha-synuclein and native DJ-1 was observed. However, DJ-1 is very susceptible to oxidation by the addition of two oxygen atoms to form the sulfinic acid of Cys106 (2O DJ-1) (no 1O oxidized state is detectable). 2O DJ-1 was readily prepared by the addition of H(2)O(2) at concentrations up to a 20-fold molar excess. The oxidation of Cys106 to the sulfinic acid had minimal effect on the structural properties of DJ-1. However, 2O DJ-1 was very effective in preventing the fibrillation of alpha-synuclein, and only this form of DJ-1 appears to have significant anti-aggregation properties against alpha-synuclein. Further oxidation of DJ-1 leads to loss of some secondary structure, and to loss of the ability to inhibit alpha-synuclein fibrillation. Our observations confirm the suggestion that DJ-1 may act as an oxidative-stress-induced chaperone to prevent alpha-synuclein fibrillation. Since oxidative stress has been associated with PD, this observation may explain why mutations of DJ-1 could be a contributing factor in PD, and also indicates that excess oxidative stress could also lead to enhanced alpha-synuclein aggregation and hence PD.
 ...
PMID:The oxidation state of DJ-1 regulates its chaperone activity toward alpha-synuclein. 1640 19

Mutations in the DJ-1 gene are associated with rare forms of autosomal recessive early-onset Parkinson's disease (PD). Although the precise physiological function of DJ-1 remains obscure, accumulating evidence suggests that DJ-1 may normally function as a redox-sensitive molecular chaperone that can protect against the deleterious effects of oxidative stress, particularly in mitochondria. Recent studies in the fruit fly, Drosophila melanogaster, have shed further light on the biological role of DJ-1. DJ-1-deficient Drosophila models exhibit distinct phenotypes but collectively highlight a prominent neuroprotective role for DJ-1 against oxidative insult. However, Drosophila lacking DJ-1 do not consistently produce a useful PD-like phenotype (that is, they generally fail to exhibit degeneration of neurons that contain the neurotransmitter dopamine), which may reflect putative compensatory neuroprotective mechanisms. DJ-1-deficient fly models further highlight the utility of Drosophila as an important tool for elucidating protein function and for modeling neurodegenerative disease.
 ...
PMID:Lessons from Drosophila models of DJ-1 deficiency. 1640 72

Sporadic Parkinson's disease (PD) is most likely caused by a combination of environmental exposures and genetic susceptibilities, although there are rare monogenic forms of the disease. Mitochondrial impairment at complex I, oxidative stress, alpha-synuclein aggregation, and dysfunctional protein degradation, have been implicated in PD pathogenesis, but how they are related to each other is unclear. To further evaluated PD pathogenesis here, we used in vivo and in vitro models of chronic low-grade complex I inhibition with the pesticide rotenone. Chronic rotenone exposure in vivo caused oxidative modification of DJ-1, accumulation of alpha-synuclein, and proteasomal impairment. Interestingly, the effects become more regionally restricted such that systemic complex I inhibition eventually results in highly selective degeneration of the nigrostriatal pathway. DJ-1 modifications, alpha-synuclein accumulation, and proteasomal dysfunction were also seen in vitro and these effects could be prevented with alpha-tocopherol. Thus, chronic exposure to a pesticide and mitochondrial toxin brings into play three systems, DJ-1, alpha-synuclein, and the ubiquitin-proteasome system, and implies that mitochondrial dysfunction and oxidative stress link environmental and genetic forms of the disease.
 ...
PMID:Intersecting pathways to neurodegeneration in Parkinson's disease: effects of the pesticide rotenone on DJ-1, alpha-synuclein, and the ubiquitin-proteasome system. 1643 41

The deposition of alpha-synuclein (aS), a product of pathogenic gene for dominantly inherited familial Parkinson's disease (PD; park1), as fibrillary aggregates like Lewy bodies (LB), is a hallmark lesion of a set of neurodegenerative disorders termed synucleinopathies, including sporadic PD and dementia with Lewy bodies (DLB). We found that aS is the major component of LBs and further identified a specific phosphorylation of Ser129 of insoluble aS by mass spectrometric analysis. The roles of DJ-1 and PINK-1, products of pathogenic genes for autosomal recessive forms of early-onset parkinsonism, have subsequently been examined. Overexpression of DJ-1 conferred cultured cells resistance to oxidative stress, suggesting an antioxidant function of DJ-1. We also confirmed the anti-PTEN function of DJ-1 that may promote cell survival, showing decreased phosphorylation of Akt through upregulation of PTEN activity upon siRNA knockdown for DJ-1. PINK-1, that had been identified as a gene upregulated by PTEN overexpression, turned out to be a protein kinase localized in mitochondria. Collectively, information derived from studies on pathogenic genes for familial PD will open up the way toward the clarification of the pathogenesis of PD, underscoring the roles of protein aggregation, proteolysis, oxidative stress and protein phosphorylation in PD.
 ...
PMID:[Pathogenesis of Parkinson's disease: implications from familial Parkinson's disease]. 1644 57

Mutations in DJ-1 cause an autosomal recessive, early onset familial form of Parkinson disease (PD). However, little is presently known about the role of DJ-1 in the more common sporadic form of PD and in other age-related neurodegenerative diseases, such as Alzheimer disease (AD). Here we report that DJ-1 is oxidatively damaged in the brains of patients with idiopathic PD and AD. By using a combination of two-dimensional gel electrophoresis and mass spectrometry, we have identified 10 different DJ-1 isoforms, of which the acidic isoforms (pI 5.5 and 5.7) of DJ-1 monomer and the basic isoforms (pI 8.0 and 8.4) of SDS-resistant DJ-1 dimer are selectively accumulated in PD and AD frontal cortex tissues compared with age-matched controls. Quantitative Western blot analysis shows that the total level of DJ-1 protein is significantly increased in PD and AD brains. Mass spectrometry analyses reveal that DJ-1 is not only susceptible to cysteine oxidation but also to previously unsuspected methionine oxidation. Furthermore, we show that DJ-1 protein is irreversibly oxidized by carbonylation as well as by methionine oxidation to methionine sulfone in PD and AD. Our study provides new insights into the oxidative modifications of DJ-1 and indicates association of oxidative damage to DJ-1 with sporadic PD and AD.
 ...
PMID:Oxidative damage of DJ-1 is linked to sporadic Parkinson and Alzheimer diseases. 1651 9

Parkinson's disease (PD) is a progressive neurodegenerative disease caused by loss of dopaminergic neurons in the substantia nigra pars compacta. Although the etiology of PD remains unclear, it is now clear that genetic factors contribute to the pathogenesis of the disease. Recently, several causative genes have been identified in monogenic forms of PD. Accumulating evidence indicates that their gene products play important roles in mitochondrial function, oxidative stress response, and the ubiquitin-proteasome system, which are also implicated in sporadic PD, suggesting that these gene products share a common pathway to nigral degeneration in both familial and sporadic PD. Here, we review recent advances in knowledge about genes associated with recessive PD, including parkin, PINK1, and DJ-1.
 ...
PMID:Recessive Parkinson's disease. 1661 60

Mutations in genes encoding both DJ-1 and pten-induced kinase 1 (PINK1) are independently linked to autosomal recessive early-onset familial forms of Parkinson's disease (PD). We here report identification of a family with PD patients harboring novel heterozygous missense mutations in both PINK1 and DJ-1 genes encoding DJ-1A39S and PINK1P399L, respectively. In transfected cells, DJ-1 interacts with PINK1. PINK1P399L is less stable than the wild-type protein and is degraded via the ubiquitin-mediated proteasomal pathway. Expression of wild-type DJ-1 increased steady-state levels of PINK1, whereas expression of DJ-1A39S reduced steady-state levels of PINK1. Furthermore, co-expression of wild-type DJ-1 and PINK1 suppresses neurotoxin 1-methyl-4-phenylpyridinium (MPP(+))-induced death of dopaminergic SH-SY5Y cells. In contrast, co-expression of PD-associated DJ-1A39S and PINK1P399L significantly potentiated susceptibility of SH-SY5Y cells to MPP(+)-induced cell death. This study reports the first case of autosomal recessive PD with digenic inheritance and demonstrates that DJ-1 and PINK1 physically associate and collaborate to protect cells against stress via complex formation.
 ...
PMID:Association of PINK1 and DJ-1 confers digenic inheritance of early-onset Parkinson's disease. 1663 86

DJ-1 is an antioxidant protein whose loss of function by gene mutations has been linked to familial Parkinson's disease (PD). The main objective of the present study was to determine if this molecule was also involved in the pathogenesis of sporadic PD. For this purpose, quantitative immunoblot assays were performed to evaluate DJ-1 in cerebrospinal fluids (CSF) collected from sporadic PD patients (n=40) and non-PD controls (n=38). The results showed that the CSF DJ-1 levels in PD were significantly higher than those in non-PD controls. Especially, upregulation of CSF DJ-1 in the early stage of PD (Yahr I-II) were distinct compared to those in the advanced stage of PD (Yahr III-IV) and non-PD controls (p<0.001 by ANOVA with post hoc Bonferroni's test), suggesting a protective role of DJ-1 against oxidative stress during the early stage. Thus, we propose that CSF DJ-1 could be a possible biomarker for early sporadic PD.
 ...
PMID:Increased level of DJ-1 in the cerebrospinal fluids of sporadic Parkinson's disease. 1670 95

Loss-of-function mutations in DJ-1 cause a subset of familial Parkinson disease (PD). However, the mechanism underlying the selective vulnerability in dopaminergic pathway due to the inactivation of DJ-1 is unclear. Previously, we have reported that DJ-1 is a neuroprotective transcriptional co-activator interacting with the transcriptional co-repressor pyrimidine tract-binding protein-associated splicing factor (PSF). Here we show that DJ-1 and PSF bind and regulate the human tyrosine hydroxylase (TH) promoter. Inactivation of DJ-1 by small interference RNA (siRNA) results in decreased TH expression and l-DOPA production in human dopaminergic cell lines. Consistent with its role as a transcriptional regulator, DJ-1 specifically suppresses the global SUMO-1 modification. High molecular weight sumoylated protein species, including PSF, accumulate in the lymphoblast cells from the patients carrying pathogenic DJ-1 mutations. DJ-1 elevates the TH expression by inhibiting the sumoylation of PSF and preventing its sumoylation-dependent recruitment of histone deacetylase 1. Furthermore, siRNA silencing of DJ-1 decreases the acetylation of TH promoter-bound histones, and histone deacetylase inhibitors restore the DJ-1 siRNA-induced repression of TH. Therefore, our results suggest DJ-1 as a regulator of protein sumoylation and directly link the loss of DJ-1 expression and transcriptional dysfunction to impaired dopamine synthesis.
 ...
PMID:DJ-1 transcriptionally up-regulates the human tyrosine hydroxylase by inhibiting the sumoylation of pyrimidine tract-binding protein-associated splicing factor. 1673 28


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