Does neuronal expression of GDNF effectively protect dopaminergic neurons in a rat model of Parkinson's disease?

The transfer of the Glial cell line-derived neurotrophic factor (GDNF) gene to the central nervous system by a recombinant adenoviral vector (Ad) was studied. We constructed the adenovirus vector Ad-NSE-GDNF from which the E1, E3/E4 regions of Ad5 have been deleted and in which the GDNF gene was under the control of a neuron-specific enolase (NSE) promoter. The vector was injected into the striatum of a rat model of Parkinson's disease. We found that (i) the NSE promoter can restrict transgene expression in neurons; (ii) Ad-NSE-GDNF significantly protected dopaminergic (DA) neurons in the substantia nigra (SN) but did not reverse the impairments of amphetamine-induced rotational behavior in lesioned rats.