title: Effect of the overexpression of wild-type or mutant alpha-synuclein on cell susceptibility to insult.
abstract: Mutations in alpha-synuclein (A30P and A53T) are involved in some cases of familial Parkinson's disease (FPD), but it is not known how they result in nigral cell death. We examined the effect of alpha-synuclein overexpression on the response of cells to various insults. Wild-type alpha-synuclein and alpha-synuclein mutations associated with FPD were overexpressed in NT-2/D1 and SK-N-MC cells. Overexpression of wild-type alpha-synuclein delayed cell death induced by serum withdrawal or H(2)O(2), but did not delay cell death induced by 1-methyl-4-phenylpyridinium ion (MPP(+)). By contrast, wild-type alpha-synuclein transfectants were sensitive to viability loss induced by staurosporine, lactacystin or 4-hydroxy-2-trans-nonenal (HNE). Decreases in glutathione (GSH) levels were attenuated by wild-type alpha-synuclein after serum deprivation, but were aggravated following lactacystin or staurosporine treatment. Mutant alpha-synucleins increased levels of 8-hydroxyguanine, protein carbonyls, lipid peroxidation and 3-nitrotyrosine, and markedly accelerated cell death in response to all the insults examined. The decrease in GSH levels was enhanced in mutant alpha-synuclein transfectants. The loss of viability induced by toxic insults was by apoptosic mechanism. The presence of abnormal alpha-synucleins in substantia nigra in PD may increase neuronal vulnerability to a range of toxic agents.
authors.affiliation: Wolfson Centre for Age-Related Diseases, Guy's, King's and St Thomas' School of Biomedical Sciences, King's College London, UK.
authors.forename: M
authors.initials: M
authors.lastname: Lee
authors.forename: D
authors.initials: D
authors.lastname: Hyun
authors.forename: B
authors.initials: B
authors.lastname: Halliwell
authors.forename: P
authors.initials: P
authors.lastname: Jenner
mesh_terms: D015655:1-Methyl-4-phenylpyridinium / Q000494:pharmacology; D000447:Aldehydes / Q000378:metabolism / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics; D002999:Clone Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression; D005978:Glutathione / Q000378:metabolism; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007659:Ketones / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects / Q000235:genetics; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics*; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D020734:Parkinsonian Disorders / Q000235:genetics* / Q000378:metabolism*; D051843:Synucleins; D018243:Teratocarcinoma / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism; D051844:alpha-Synuclein
chemical_list: D000447:Aldehydes; D016895:Culture Media, Serum-Free; D004791:Enzyme Inhibitors; D007659:Ketones; D009419:Nerve Tissue Proteins; D016877:Oxidants; C497604:SNCA protein, human; D051843:Synucleins; D051844:alpha-Synuclein; C002744:3-nitrotyrosine; D014443:Tyrosine; C024829:8-hydroxyguanine; D006147:Guanine; D006861:Hydrogen Peroxide; D005978:Glutathione; C027576:4-hydroxy-2-nonenal; D015655:1-Methyl-4-phenylpyridinium