Novel models for Parkinson's disease and their impact on future drug discovery.

INTRODUCTION: Parkinson's disease is a progressive neurodegenerative disease that affects millions of elderly individuals worldwide. Despite intensive efforts dedicated to find a better treatment, the pathogenesis of Parkinson's Disease remains unknown. In search for a better therapy for the disease, several new in vivo and in vitro models of Parkinson´s disease have been developed in recent times. Areas covered: The authors provide an outline of the various traditional models of Parkinson´s disease and address those that have been recently generated. They also discuss the utility of these models for the identification of drugs of potential therapeutic value for Parkinson´s Disease patients. From the cell based models and the well-known toxin-based animal models, to the recent genetic models and the increasingly used non-mammalian models, every model is worthwhile in the search for a better Parkinson´s Disease therapy. Expert opinion: Almost 60 years after its discovery, levodopa is still the gold standard treatment for Parkinson's Disease patients. It seems unlikely that a single model can fully recapitulate the complexity of Parkinson's Disease in the same way it appears improbable that a unique treatment could relieve both the motor and non-motor symptoms of Parkinson's Disease altogether. Therefore treatment will probably require a combination of therapies.