MULTILINE IPSC-BASED DRUG REPURPOSING IDENTIFIES N-ACETYLCYSTEINE AND FELODIPINE AS NEUROPROTECTIVE AGENTS ACROSS DISTINCT GENETIC FORMS OF PARKINSON’S DISEASE

Drug repurposing is a promising strategy for developing disease-modifying therapies for Parkinson’s Disease (PD). In this context, N-acetylcysteine (NAC) and Felodipine (FEL) have shown potential to preserve dopaminergic function and modulate key PD mechanisms. Here, we used in vitro neurodegenerative disease models to assess their neuroprotective potential across distinct neuronal contexts.
Using iPSC-derived cortical neurons (G3dCas9 i3N) and dopaminergic neurons (DAn) from healthy donors and PD patients carrying either SNCA or GBA mutations, we developed a controlled 6-Hydroxydopamine (6-OHDA) toxicity paradigm. Four toxic conditions (10, 15, 25, and 50µM) were selected to induce graded neurodegeneration while preserving sufficient neuronal viability for mechanistic studies. Neuronal responses were profiled across multiple disease-relevant readouts, including cell viability, lipid droplet dynamics, mitochondrial morphology, autophagy function (DQ-BSA), and metabolic state (Seahorse assay). Subsequently, four concentrations of NAC and FEL were tested in each neuronal line and under each toxic condition.
In cortical neurons, NAC provided strong, dose-dependent neuroprotection, especially under severe toxic stress (50µM), whereas FEL offered context-dependent protection across varying toxic burdens. Both compounds significantly modulated mitochondrial context (increased TOM20 area and number), lipid metabolism (altered lipid droplet formation), autophagy activity (lysosomal activity and number), and cellular bioenergetics. In DAn lines, genotype-dependent vulnerability to 6OHDA was observed, while control lines responded uniformly to identical stimuli. Using a multi-line screening approach, NAC and FEL conferred modulatory effects across control, SNCA, and GBA backgrounds.
Together, these findings identify NAC and FEL as multimodal agents that target convergent PD hallmarks across distinct human neuronal populations.