Dose Optimization for Long-term rAAV-mediated RNA Interference in the Nigrostriatal Projection Neurons.
Författare
Summary, in English
Short-hairpin RNA (shRNA)-mediated gene knockdown is a powerful tool for targeted gene silencing and an emerging novel therapeutic strategy. Recent publications, however, reported unexpected toxicity after utilizing viral-mediated shRNA knockdown in vivo. Thus, it is currently unclear whether shRNA-mediated knockdown strategy can be used as a safe and efficient tool for gene silencing. In this study, we have generated rAAV vectors expressing shRNAs targeting the rat tyrosine hydroxylase (TH) mRNA (shTH) for testing the efficacy of in vivo TH knockdown in the nigral dopaminergic neurons. At high titers, not only the shTH vectors but also the scrambled and green fluorescence protein (GFP)-only controls caused cell death. In a dose-response study, we identified a dose window leading to >60% decrease in TH(+) neurons without any change in vesicular monoamine transporter-2 (VMAT2) expression. Moreover, using the safe and efficient dose, we showed that dopamine (DA) synthesis rate was significantly reduced and this lead to emergence of motor deficits in the shTH-expressing rats. Interestingly, these animals showed very robust and long-lasting recovery after a single systemic L-3,4-dihydroxyphenylalanine (L-DOPA) administration beyond what can be achieved in 6-hydroxydopamine (6-OHDA)-lesioned rats. Our results have implications for both mechanistic and therapeutic studies utilizing long-term shRNA-mediated gene silencing in the nigrostriatal projection system.Molecular Therapy (2009); doi:10.1038/mt.2009.142.
Publiceringsår
2009
Språk
Engelska
Sidor
1574-1584
Publikation/Tidskrift/Serie
Molecular Therapy
Volym
17
Fulltext
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Nature Publishing Group
Ämne
- Medical Genetics
Status
Published
Forskningsgrupp
- Brain Repair and Imaging in Neural Systems (BRAINS)
ISBN/ISSN/Övrigt
- ISSN: 1525-0024