Neuropathology of Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative movement disorder of great concern of which no proven neuroprotective or neurorestorative therapies are available. It is characterized mainly by the degeneration of dopamine (DA) producing neurons in the substantia nigra (SN) pars compacta (SNpc) resulting in nigrostriatal pathway dysregulation and eventually disturbed subcortico-cortical interactions. The pathophysiological mechanisms leading to PD development are not completely understood. Several mechanisms and pathway dysfunctions have been proposed as they play a critical role in the pathogenesis of PD. These include oxidative stress, dysfunctional mitochondria, neuroinflammation, ubiquitin proteasomal dysfunction, and α-synuclein protein aggregation. This chapter will provide an overview on neuropathology, pathogenesis, and the recent pathophysiological mechanisms involved in PD.