M. Grazia Cotticelli, Shujuan Xia, Daniel Lin, Taehee Lee, Leila Terrab, Peter Wipf, Donna Huryn and Robert Wilson
Journal of Pharmacology and Experimental Therapeutics January 11, 2019, jpet.118.252759; DOI:10.1124/jpet.118.252759
Ferropotosis is a recently identified pathway of regulated, iron-dependent cell death, which is biochemically distinct from apoptosis. We evaluated whether there is evidence for ferroptotic pathway activation in cellular models of FRDA. We found that primary patient-derived fibroblasts, murine fibroblasts with FRDA-associated mutations, and murine fibroblasts in which a repeat expansion had been introduced (KIKO) were more sensitive than normal control cells to erastin, a known ferroptosis inducer. We also found that the ferroptosis inhibitors SRS11-92 and Fer-1, used at 500 nM, were efficacious in protecting human and mouse cellular models of FRDA treated with ferric ammonium citrate (FAC) and an inhibitor of glutathione synthesis (BSO), whereas caspase-3 inhibitors failed to show significant biological activity. Cells treated with FAC and BSO consistently showed decreased glutathione-dependent peroxidase activity and increased lipid peroxidation, both hallmarks of ferroptosis. Finally, the ferroptosis inhibitor SRS11-92 decreased the cell death associated with frataxin knockdown in healthy human fibroblasts. Taken together, these data suggest that ferroptosis inhibitors may have therapeutic potential in FRDA.
Ferroptosis as a novel therapeutic target for Friedreich's ataxia