Gene-corrected p.A30P SNCA patient-derived isogenic neurons rescue neuronal branching and function

Peter A Barbuti,Rejko Krüger,Lukas Pavelka,Bruno F R Santos,Yong-Jun Kwon,Jochen Ohnmacht,Gérald Cruciani,Nicolas Casadei,Paul M Antony,Claire M Dording,François Massart

doi:10.1038/s41598-021-01505-x

Abstract

Parkinson’s disease (PD) is characterised by the degeneration of A9 dopaminergic neurons and the pathological accumulation of alpha-synuclein. The p.A30P SNCA mutation generates the pathogenic form of the alpha-synuclein protein causing an autosomal-dominant form of PD. There are limited studies assessing pathogenic SNCA mutations in patient-derived isogenic cell models. Here we provide a functional assessment of dopaminergic neurons derived from a patient harbouring the p.A30P SNCA mutation. Using two clonal gene-corrected isogenic cell lines we identified image-based phenotypes showing impaired neuritic processes. The pathological neurons displayed impaired neuronal activity, reduced mitochondrial respiration, an energy deficit, vulnerability to rotenone, and transcriptional alterations in lipid metabolism. Our data describes for the first time the mutation-only effect of the p.A30P SNCA mutation on neuronal function, supporting 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.

Highlights

Parkinson’s disease (PD) is a neurodegenerative disease with no current causative treatment
We assessed the neuronal connectivity using multi-electrode array (MEA) technology and find reduced neuronal function in the patient neurons carrying the p.A30P mutation in SNCA. We find that these ventral midbrain dopaminergic (vmDA) neurons display a reduced mitochondrial respiration, a clear energy deficit shown by loss of ATP, reduced mitochondrial membrane potential (MMP) and a high level of mitochondrial superoxide
To control for the influence of the genetic background we assessed the bioenergetic profile of neurons directly differentiated from two different iPS clones carrying the A30P mutation, which we have previously characterised[34]. Comparing these pathological neurons against neurons from an age- and gender-matched nonPD control[35], we find that the bioenergetic profile of both clonal cell lines carrying the A30P alpha-synuclein mutation align, with mitochondrial respiration and ATP production significantly reduced compared to the control

Summary

Introduction

Parkinson’s disease (PD) is a neurodegenerative disease with no current causative treatment. We treated these neurons using rotenone as an environmental toxin model for PD and found that the neurons carrying the A30P mutation in alpha-synuclein have a specific reduction in neuronal viability compared to both gene-corrected iPS-derived controls.

Results

Conclusion