Enabling phenotypic drug discovery for neurological mitochondrial DNA disorders with patient-derived neural progenitor cells

Mitochondrial DNA (mtDNA) mutations predominantly cause neurological diseases. Searching for therapeutic strategies is hindered by the absence of viable neural model systems due to the challenges of engineering mtDNA. We demonstrate that neural progenitor cells (NPCs), rapidly obtained from human induced pluripotent stem cells (iPSCs), retain the parental mtDNA profile and exhibit mitochondrial maturation coupled with a metabolic switch away from glycolysis. Altered calcium homeostasis and mitochondrial hyperpolarization, both potential causes of neural impairment, were observed in iPSC-derived NPCs from patients carrying a deleterious homoplasmic mutation in the mitochondrial gene MT-ATP6 (m.9185T>C). Phenotype-based high-content screenings (HCS) with FDA-approved compounds were carried out, leading to the identification of possible innovative counteracting agents. We propose iPSC-derived NPCs, displaying mild proliferative properties and proper genotype/metabotype, as a bona fide model system for the establishment of personalized phenotypic drug discovery for untreatable mtDNA disorders affecting the nervous system. Associated GEO accession number: GSE70071.