Parkinson's disease and neuroprotection: Dream or reality?

Neuroprotection has been successfully applied using various in vitro and in vivo models for Parkinson's disease. Unfortunately, the translation of such positive results into clinical practice has not been possible. We believe that one of the main issues is the lack of an appropriate animal model with specific chronic progressive degeneration of dopaminergic neurons. However, recent clinical trials comparing the progression of the functional decline of dopaminergic neurons under treatment with a dopamine agonist compared with L-DOPA indicated that the degeneration of dopaminergic neurons is less pronounced when patients are treated with a dopamine agonist. The function of dopaminergic neurons was assessed using quantification of either FDOPA uptake or dopamine transporter binding. Whether dopamine agonists exert a true neuroprotective effect remains unknown as long as comparable data on the natural course are pending. There is considerable hope that neuroprotection will be proven in up-coming clinical trials.