title: Differential effects of carboxyfullerene on MPP+/MPTP-induced neurotoxicity.
abstract: The effects of carboxyfullerene on a well-known neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its active metabolite 1-methyl-4-phenyl-pyridinium (MPP+) were investigated. In chloral hydrate-anesthetized rats, cytosolic cytochrome c was elevated in the infused substantia nigra 4 h after an intranigral infusion of MPP+. Five days after local application of MPP+, lipid peroxidation (LP) was elevated in the infused substantia nigra. Furthermore, dopamine content and tyrosine hydroxylase (TH)-positive axons were reduced in the ipsilateral striatum. Concomitant intranigral infusion of carboxyfullerene abolished the elevation in cytochrome c and oxidative injuries induced by MPP+. In contrast, systemic application of carboxyfullerene did not prevent neurotoxicity induced by intraperitoneal injection of MPTP. In mice, systemic administration of MPTP induced a dose-dependent depletion in striatal dopamine content. Simultaneous injection of carboxyfullerene (10 mg/kg) actually potentiated MPTP-induced reduction in striatal dopamine content. Furthermore, systemic administration of carboxyfullerene (30 mg/kg) caused death in the MPTP-treated mice. An increase in the striatal MPP+ level and reduction in hepatic P450 level were observed in the carboxyfullerene co-treated mice. These data showed that systemic application of carboxyfullerene appears to potentiate MPTP-induced neurotoxicity while local carboxyfullerene has been suggested as a neuroprotective agent. Furthermore, an increase in striatal MPP+ level may contribute to the potentiation by carboxyfullerene of MPTP-induced neurotoxicity.
authors.affiliation: Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Anya M Y
authors.initials: AM
authors.lastname: Lin
authors.forename: C H
authors.initials: CH
authors.lastname: Yang
authors.forename: Y-F
authors.initials: YF
authors.lastname: Ueng
authors.forename: T Y
authors.initials: TY
authors.lastname: Luh
authors.forename: T Y
authors.initials: TY
authors.lastname: Liu
authors.forename: Y P
authors.initials: YP
authors.lastname: Lay
authors.forename: L T
authors.initials: LT
authors.lastname: Ho
mesh_terms: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001369:Axons / Q000201:enzymology / Q000378:metabolism; D015153:Blotting, Western; D002264:Carboxylic Acids / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003574:Cytochrome c Group / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D015259:Dopamine Agents / Q000633:toxicity*; D004563:Electrochemistry; D037741:Fullerenes; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D051379:Mice; D008845:Microinjections; D017072:Neostriatum / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D011726:Pyridinium Compounds / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013378:Substantia Nigra / Q000187:drug effects / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: C416673:C60 carboxyfullerene; D002264:Carboxylic Acids; D003574:Cytochrome c Group; D015259:Dopamine Agents; D037741:Fullerenes; D011726:Pyridinium Compounds; C026560:1-(4-methoxyphenyl)pyridinium; D003577:Cytochrome P-450 Enzyme System; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine