title: Parkin-mediated protection of dopaminergic neurons in a chronic MPTP-minipump mouse model of Parkinson disease.
abstract: Loss-of-function mutations in the ubiquitin ligase parkin are the major cause of recessively inherited early-onset Parkinson disease (PD). Impairment of parkin activity caused by nitrosative or dopamine-related modifications may also be responsible for the loss of dopaminergic (DA) neurons in sporadic PD. Previous studies have shown that viral vector-mediated delivery of parkin prevented DA neurodegeneration in several animal models, but little is known about the neuroprotective actions of parkin in vivo. Here, we investigated mechanisms of neuroprotection of overexpressed parkin in a modified long-term mouse model of PD using osmotic minipump administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Recombinant adeno-associated viral vector-mediated intranigral delivery of parkin prevented motor deficits and DA cell loss in the mice. Ser129-phosphorylated α-synuclein-immunoreactive cells were increased in the substantia nigra of parkin-treated mice. Moreover, delivery of parkin alleviated the MPTP-induced decrease of the active phosphorylated form of Akt. On the other hand, upregulation of p53 and mitochondrial alterations induced by chronic MPTP administration were barely suppressed by parkin. These results suggest that the neuroprotective actions of parkin may be impaired in severe PD.
authors.affiliation: Department of Neurology, Kitasato University School of Medicine, Minami-ku, Sagamihara, Kanagawa, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Yasuda
authors.forename: Hideki
authors.initials: H
authors.lastname: Hayakawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Nihira
authors.forename: Yong-Ri
authors.initials: YR
authors.lastname: Ren
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Nakata
authors.forename: Makiko
authors.initials: M
authors.lastname: Nagai
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Hattori
authors.forename: Koichi
authors.initials: K
authors.lastname: Miyake
authors.forename: Masahiko
authors.initials: M
authors.lastname: Takada
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimada
authors.forename: Yoshikuni
authors.initials: Y
authors.lastname: Mizuno
authors.forename: Hideki
authors.initials: H
authors.lastname: Mochizuki
mesh_terms: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine / Q000008:administration & dosage; D000704:Analysis of Variance; D000818:Animals; D002452:Cell Count / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003342:Corpus Striatum / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D004298:Dopamine / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D005822:Genetic Vectors / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D020267:MPTP Poisoning / Q000139:chemically induced / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008636:Mesencephalon / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008845:Microinjections / Q000379:methods; D009043:Motor Activity / Q000187:drug effects; D009410:Nerve Degeneration / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D009474:Neurons / Q000502:physiology*; D009498:Neurotoxins / Q000008:administration & dosage; D051058:Oncogene Protein v-akt / Q000378:metabolism; D045442:Rotarod Performance Test; D015398:Signal Transduction / Q000187:drug effects; D013223:Statistics as Topic; D014161:Transduction, Genetic / Q000379:methods; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use*; D051844:alpha-Synuclein / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D009498:Neurotoxins; D016159:Tumor Suppressor Protein p53; D051844:alpha-Synuclein; D051028:bcl-2-Associated X Protein; D049452:Green Fluorescent Proteins; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D044767:Ubiquitin-Protein Ligases; C111567:parkin protein; D051058:Oncogene Protein v-akt; D004298:Dopamine