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bioRxiv · 10.1101/2022.11.07.515284

Rescue of the increased susceptibility to Mild Chronic Oxidative Stress of iNeurons carrying the MAPT Chromosome 17q21.3 H1/H1 risk allele by FDA-approved compounds

Abstract

The microtubule associated protein tau (MAPT) chromosome 17q21.31 locus lies within a region of high linkage disequilibrium (LD) conferring two extended haplotypes commonly referred to as H1 and H2. The major haplotype, H1 has been genetically associated with an increased risk for multiple neurodegenerative disorders, including Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), APOE {varepsilon}4-negative Alzheimers disease (AD) and Parkinsons disease (PD). The mechanism causing this increased risk is largely unknown. Here, we investigated the role of Mild Chronic Oxidative Stress (MCOS) in neurogenin 2 (NGN2) induced neurons (iNeurons) derived from iPS (induced pluripotent stem cells) from carriers of both haplotypes. We identified that iNeurons of the H1 homozygous haplotype showed an increased susceptibility to MCOS compared to homozygous H2 carriers, leading to cell death through ferroptosis. We performed a cellular screen in H1 iNeurons using a FDA-approved Drug Library and identified candidate molecules that rescued the increased susceptibility to MCOS and prevented ferroptosis in H1 iNeurons. HighlightsO_LIMild Chronic Oxidative Stress induces neurotoxicity via ferroptosis on iNGN2 neurons C_LIO_LIAxonal degeneration, disordered microtubules, blebs precede neurotoxicity C_LIO_LIMAPT-17q21.3 locus H1/H1, risk allele for NDD is more vulnerable to MCOS C_LIO_LIFDA-approved drugs reverse MCOS induced ferroptosis on H1/H1 risk allele C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=158 SRC="FIGDIR/small/515284v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@eddb2eorg.highwire.dtl.DTLVardef@1d0c00dorg.highwire.dtl.DTLVardef@1f0b00eorg.highwire.dtl.DTLVardef@b68f1b_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Sadikoglou, E., Domingo-Fernandez, D., Savytska, N., Fernandes, N., Rizzu, P., Illarionova, A., Strauss, T., Schwarz, S., Kodamullil, A., Hoeglinger, G., Dhingra, A., Heutink, P.. 2022-11-07. Rescue of the increased susceptibility to Mild Chronic Oxidative Stress of iNeurons carrying the MAPT Chromosome 17q21.3 H1/H1 risk allele by FDA-approved compounds. https://doi.org/10.1101/2022.11.07.515284

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