Dataset Information

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

ABSTRACT: 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.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Alessandro Prigione

PROVIDER: MSV000080849 | MassIVE | Fri Mar 31 22:32:00 BST 2017

SECONDARY ACCESSION(S): PXD004977

REPOSITORIES: MassIVE

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Publications

Human iPSC-Derived Neural Progenitors Are an Effective Drug Discovery Model for Neurological mtDNA Disorders.

Lorenz Carmen C Lesimple Pierre P Bukowiecki Raul R Zink Annika A Inak Gizem G Mlody Barbara B Singh Manvendra M Semtner Marcus M Mah Nancy N Auré Karine K Leong Megan M Zabiegalov Oleksandr O Lyras Ekaterini-Maria EM Pfiffer Vanessa V Fauler Beatrix B Eichhorst Jenny J Wiesner Burkhard B Huebner Norbert N Priller Josef J Mielke Thorsten T Meierhofer David D Izsvák Zsuzsanna Z Meier Jochen C JC Bouillaud Frédéric F Adjaye James J Schuelke Markus M Wanker Erich E EE Lombès Anne A Prigione Alessandro A

Cell stem cell 20170126 5

Mitochondrial DNA (mtDNA) mutations frequently cause neurological diseases. Modeling of these defects has been difficult because of the challenges associated with engineering mtDNA. We show here that neural progenitor cells (NPCs) derived from human induced pluripotent stem cells (iPSCs) retain the parental mtDNA profile and exhibit a metabolic switch toward oxidative phosphorylation. NPCs derived in this way from patients carrying a deleterious homoplasmic mutation in the mitochondrial gene MT- ...[more]

PMID: 28132834

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Project description:Mutations in the E3 ubiquitin ligase Parkin cause autosomal recessive Parkinson’s disease. In concert with PINK1, Parkin regulates the clearance of dysfunctional mitochondria via lysosomes. In response, new mitochondria are generated through an interplay of nuclear- and mitochondrial-encoded proteins. Mouse and overexpression models suggests that Parkin also influences these processes, both in the nuclear cascade and at the level of the mitochondrial genome. Additionally, Parkin has been shown to prevent mitochondrial membrane permeation, impeding the escape of mitochondrial DNA (mtDNA). In line with this, serum from Parkin mutation carriers showed higher levels of circulating cell-free mtDNA (ccf-mtDNA) and inflammatory cytokines – a result of the innate immune response - which can be triggered by cytosolic mtDNA. However, Parkin’s relationship with the mitochondrial genome and the mitogenesis pathway has not been explored in patient-derived neurons. To investigate this aspect of Parkin’s cellular function endogenously, we generated induced pluripotent stem cell (iPSC)-derived midbrain neurons from Parkin mutation carriers and healthy controls. In Parkin-deficient cells, several factors in the mitochondrial biogenesis pathway were significantly reduced, resulting in impaired mtDNA homeostasis - a phenomenon that was exacerbated in dopaminergic neurons. Moreover, in response to a lack of freely accessible NAD+, the energy sensor Sirtuin 1, which simultaneously controls mtDNA maintenance processes and mitophagy, was downregulated in Parkin-deficient neurons. However, while impaired lysosomal degradation of mitochondria was only detectable in oxidative conditions, biogenesis defects were already apparent in untreated patient neurons. This may suggest that mitophagy disruption occurs in response to acute stress. By contrast, the biogenesis pathway may be continually impaired in Parkin-associated Parkinson’s disease. Next, using a mutagenic stress model in combination with Parkin knockdown, we detected an increase in ccf-mtDNA and the cytosolic DNA sensor cGAS. To explore if ccf-mtDNA can act as damage-associated molecular pattern in the brain, we used postmortem tissue from a Parkin mutation carrier and performed single-cell RNA sequencing. In the midbrain lacking Parkin, we found a higher percentage of microglia along with an upregulation of proinflammatory cytokines in these cells. Together, our findings suggest a role for Parkin in the control of mitochondrial biogenesis and mtDNA maintenance, which protects midbrain neurons from neuroinflammation-induced degeneration. Future research in iPSC-derived neuron-microglia co-culture systems could aim at developing PD treatment approaches that target the neuronal release or microglial uptake of ccf-mtDNA.

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Dataset Information

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

Publications

Human iPSC-Derived Neural Progenitors Are an Effective Drug Discovery Model for Neurological mtDNA Disorders.

Similar Datasets

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