Gene-corrected Parkinson's disease neurons show the A30P alpha-synuclein point mutation leads to reduced neuronal branching and function

Parkinson9s disease is characterised by the degeneration of A9 dopaminergic neurons and the pathological accumulation of alpha-synuclein. In a patient-derived stem cell model, we have generated dopaminergic neurons from an individual harbouring the p.A30P SNCA mutation and compared those neurons against gene-corrected isogenic control cell lines. We have used confocal microscopy to assess the neuronal network, specifically segmenting dopaminergic neurons and have identified image-based phenotypes showing axonal impairment and reduced neurite branching. We show using multi-electrode array (MEA) technology that the neurons carrying the endogenous p.A30P alpha-synuclein mutation are functionally impaired and identified mitochondrial dysfunction as a pathogenic cellular phenotype. We report that against gene-corrected isogenic control cell lines the neurons carrying the p.A30P SNCA mutation have a deficit and are susceptible to the mitochondrial toxin and environmental pesticide Rotenone. Our data supports the use of isogenic cell lines in identifying image-based pathological phenotypes that can serve as an entry point for future disease modifying compound screenings and drug discovery strategies.