Behavioral Recovery in a Primate Model of Parkinson's Disease by Triple Transduction of Striatal Cells with Adeno-Associated Viral Vectors Expressing Dopamine-Synthesizing Enzymes

Abstract

One potential strategy for gene therapy of Parkinson's disease (PD) is the local production of dopamine (DA) in the striatum induced by restoring DA-synthesizing enzymes. In addition to tyrosine hydroxylase (TH) and aromatic-L-amino-acid decarboxylase (AADC), GTP cyclohydrolase I (GCH) is necessary for efficient DA production. Using adeno-associated virus (AAV) vectors, we previously demonstrated that expression of these three enzymes in the striatum resulted in long-term behavioral recovery in rat models of PD. We here extend the preclinical exploration to primate models of PD. Mixtures of three separate AAV vectors expressing TH, AADC, and GCH, respectively, were stereotaxically injected into the unilateral putamen of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated monkeys. Coexpression of the enzymes in the unilateral putamen resulted in remarkable improvement in manual dexterity on the contralateral to the AAV-TH/-AADC/-GCH-injected side. Behavioral recovery persisted during the observation period (four monkeys: 48 days, 65 days, 50 days, and >10 months, each). TH-immunoreactive (TH-IR), AADC-IR, and GCH-IR cells were present in a large region of the putamen. Microdialysis demonstrated that concentrations of DA in the AAV-TH/-AADC/-GCH-injected putamen were increased compared with the control side. Our results show that AAV vectors efficiently introduce DA-synthesizing enzyme genes into the striatum of primates with restoration of motor functions. This triple transduction method may offer a potential therapeutic strategy for PD.

Neurotransmitter release: vacuolar ATPase V0 sector c-subunits in possible gene or cell therapies for Parkinson’s, Alzheimer’s, and psychiatric diseases

“…ATP6V0C plays a central role in H + transport as one part of the multi-subunit complex of ATPase [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44]. Israel and his group initially proposed that medatophore forms a proteinaceous pore by the six transmemebrane c subunits of ATPase [10,11].…”

“…The amino acid sequence and recently reported structures of the c ring of the V0 domain [44] suggest very high hydrophobicity of the inner part of the ring, which seems unsuitable for an ion channel pore. In addition, a direct interaction between ATP6V0C and the vesicular SNARE synaptobrevin and associated modulatory effects on ACh release have been reported [13,35,36]. Therefore, now it is time to carefully re-consider the role of mediatophore/ATP6V0C and thus, revisited it from the recent advances in knowledges of vacuolar ATPase.…”

“…ATP6V0C binds to syntaxin in SNARE complexes [67] or interacts directly with the v-SNARE synaptobrevin [35,36], and ATP6V0C may cooperate with SNARE proteins and vesicles for release during the late stage of fusion []. DA release through proteolipid fusion pores suggests that the vesicles may be recycled without undergoing full fusion with the plasma membrane (i.e., the "kiss-and-run" process) [51][52][53][54].…”

Long-term correction of hyperphenylalaninemia by AAV-mediated gene transfer leads to behavioral recovery in phenylketonuria mice

“…4,5 On the other hand, adeno-associated virus (AAV) vectors comprise another class of gene delivery vehicles, which have been shown to stably transduce nondividing cells such as hepatocytes, muscle fibers and neurons. [6][7][8] In this study, we evaluated a recombinant AAV vector carrying the PAH gene in a mouse model of PKU (PAH enu2 strain). [9][10][11] A missense mutation (F263S) in the PAH gene was introduced into BTBR mouse strain by chemical mutagenesis, resulting in a loss of enzyme activity.…”

Gene therapy progress and prospects: Parkinson's disease

“…Various vector systems have been used in recent preclinical studies to deliver different combinations of these enzymes. These include multicistronic lentiviruses simultaneously encoding GCH1, TH and AADC; 20 combinations of AAV vectors separately encoding GCH1 and TH 21 or GCH1, TH and AADC; 22,23 an HSV vector coexpressing AADC and TH. 24 In all cases, coexpression of the enzymes and functional recovery of the experimentally lesioned animals was observed.…”