Gene therapy in Parkinson's

The tremors and other motor symptoms characteristic of Parkinson's disease are caused by destruction of nigral dopamine neurons of the subthalamic nucleus and excessive activity of output nuclei. In October 11 Science, Jia Luo and colleagues at the University of Auckland, New Zealand show that treatment with a glutamic acid decarboxylase (GAD) gene switches the subthalamic nucleus (STN) to inhibitory neurotransmission and reduces symptoms in a Parkinson's disease rat model (Science, 298:425-429, October 11, 2002).

Luo et al. injected adeno-associated viral vectors containing the gene that encodes GAD — which catalyzes synthesis of the inhibitory neurotransmitter GABA — into the STN of rats. They observed that following injection the excitatory glutamatergic neurons in the STN started producing mixed inhibitory responses associated with GABA release. This phenotypic shift resulted in strong neuroprotection of nigral dopamine neurons and rescue of the Parkinsonian behavioral phenotype.

"This strategy suggests that there is plasticity between ...