Screening strategy using a filamentous fungus model to repurpose drugs for mitochondrial complex I deficiencies.

AIM: This study aimed to repurpose FDA-approved drugs for the treatment of mitochondrial complex I diseases.

MATERIALS AND

METHODS

The NUO-51 protein of the filamentous fungus Podospora anserina is the homolog of the human key catalytic subunit of complex I, NDUFV1. By introducing a pathogenic mutation into P. anserina NUO-51 we created a novel model of complex I deficiency targeting the NDUFV1 subunit. The thermosensitive phenotype of the fungal mutant enabled us to screen a library of nearly one thousand FDA-approved molecules. We have implemented various techniques such as growth analysis, oxygen consumption measurements, complex I activity assays and western blotting on Podospora, Caenorhabditis elegans and human on equivalent NDUFV1 mutant models, treated or untreated with the most effective drugs found during the screen.

KEY FINDINGS: We isolated a series of compounds able to rescue the growth defect of the Podospora nuo-51 mutant, including ligands of serotonin receptors or transporters. Among the selected drugs, alverine citrate (ALV) and dapoxetine hydrochloride (DAP) emerged as the most active drugs. Both drugs enhanced respiration and complex I activity, not only in the Podospora mutant, but also in Caenorhabditis elegans worms deficient for the NDUFV1 ortholog and in fibroblasts from patient carrying NDUFV1 mutations.

SIGNIFICANCE: Together, our work demonstrates the usefulness of Podospora anserina as fungal model for identifying promising therapeutic candidates for complex I diseases, paving the way for future clinical trials.