Linked Life Data

16870259

Source:http://linkedlifedata.com/resource/pubmed/id/16870259

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2006-8-21
pubmed:abstractText
Impairment in ubiquitin-proteasome system (UPS) has recently been implicated in Parkinson's disease, as demonstrated by reduced proteasomal activities, protein aggregation and mutation of several genes associated with UPS. However, experimental studies with proteasome inhibitors failed to yield consensus regarding the effect of proteasome inhibition on dopaminergic degeneration. In this study, we systematically examined the effect of the proteasome inhibitor MG-132 on dopaminergic degeneration in cell culture and animal models of Parkinson's disease. Exposure of immortalized dopaminergic neuronal cells (N27) to low doses of MG-132 (2-10 microM) resulted in dose- and time-dependent cytotoxicity. Further, exposure to MG-132 (5 microM) for 10 min led to dramatic reduction of proteasomal activity (>70%) accompanied by a rapid accumulation of ubiquitinated proteins in these cells. MG-132 treatment also induced increases in caspase-3 activity in a time-dependent manner, with significant activation occurring between 90 and 150 min. We also noted a 12-fold increase in DNA fragmentation in MG-132 treated N27 cells. Similarly, primary mesencephalic neurons exposed to 5 microM MG-132 also induced >60% loss of TH positive neurons but only a minimal loss of non-dopaminergic cells. Stereotaxic injection of MG-132 (0.4 microg in 4 microl) into the substantia nigra compacta (SNc) in C57 black mice resulted in significant depletion of ipisilateral striatal dopamine and DOPAC content as compared to the vehicle-injected contralateral control sides. Also, we observed a significant decrease in the number of TH positive neurons in the substantia nigra of MG-132-injected compared to the vehicle-injected sites. Collectively, these results demonstrate that the proteasomal inhibitor MG-132 induces dopamine depletion and nigral dopaminergic degeneration in both cell culture and animal models, and suggest that proteasomal dysfunction may promote nigral dopaminergic degeneration in Parkinson's disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0161-813X
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
807-15
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:16870259-Analysis of Variance, pubmed-meshheading:16870259-Animals, pubmed-meshheading:16870259-Caspase 3, pubmed-meshheading:16870259-Caspases, pubmed-meshheading:16870259-Cell Death, pubmed-meshheading:16870259-Cells, Cultured, pubmed-meshheading:16870259-Cysteine Proteinase Inhibitors, pubmed-meshheading:16870259-DNA Fragmentation, pubmed-meshheading:16870259-Disease Models, Animal, pubmed-meshheading:16870259-Dopamine, pubmed-meshheading:16870259-Dose-Response Relationship, Drug, pubmed-meshheading:16870259-Embryo, Mammalian, pubmed-meshheading:16870259-Immunohistochemistry, pubmed-meshheading:16870259-Leupeptins, pubmed-meshheading:16870259-Mesencephalon, pubmed-meshheading:16870259-Mice, pubmed-meshheading:16870259-Mice, Inbred C57BL, pubmed-meshheading:16870259-Nerve Degeneration, pubmed-meshheading:16870259-Neurons, pubmed-meshheading:16870259-Neurotransmitter Agents, pubmed-meshheading:16870259-Proteasome Endopeptidase Complex, pubmed-meshheading:16870259-Rats, pubmed-meshheading:16870259-Tyrosine 3-Monooxygenase
pubmed:year
2006
pubmed:articleTitle
Proteasome inhibitor MG-132 induces dopaminergic degeneration in cell culture and animal models.
pubmed:affiliation
Parkinson's Disorder Research Laboratory, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, 2062 Veterinary Medicine Building, Ames, IA 50011-1250, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, N.I.H., Extramural