Targeting α-Synuclein in Parkinson's Disease: Progress Towards the Development of Disease-Modifying Therapeutics.

Parkinson's disease (PD), the second most common neurodegenerative movement disorder, is characterized by progressive motor and non-motor symptoms [1]. Despite treatment with pharmacologic and surgical therapies, the disease will continue to relentlessly advance. Hence, there is a great deal of interest in potential disease-modifying therapies with the hope that the neurodegenerative process can be slowed or halted. The purpose of this review is to highlight the role toxic α-synuclein (α-syn) plays in PD pathogenesis and critically review the relevant literature about therapeutic modalities targeting α-syn. Toxic α-syn plays a key role in PD pathogenesis, disrupting important cellular functions, and, thus, targeting α-syn is a reasonable disease-modifying strategy. Current approaches under investigation include decreasing α-syn production with RNA interference (RNAi), inhibiting α-syn aggregation, promoting intracellular degradation of α-syn aggregates (via enhancing autophagy and enhancing lysosomal degradation), and promoting extracellular degradation of α-syn via active and passive immunization.