Background/Objectives: Ferroptosis, an iron-dependent form of regulated cell death defined by lipid peroxidation, has been extensively studied in cancer and neurodegeneration, but its contribution to erythropoiesis remains poorly understood. Methods: In this study, we investigated the expression of ferroptosis-related genes during HMBA-induced differentiation of murine erythroleukemia (MEL) cells and further assessed the effects of the ferroptosis inducer erastin in this model system. Results: HMBA treatment was accompanied by upregulation of ferroptosis-inducing genes (Atf3, Por, Tfrc, Slc11a2) and downregulation of inhibitory genes (Dhfr, Aifm2, Flvcr1, Nfe2l2, Slc3a2, Slc7a11), while Gpx4 levels increased. Erastin exposure identified 5 μM as the optimal concentration, which resulted in a significant reduction of Steap3 transcripts, an increase in Hbb expression, and an increased accumulation of differentiated cells in culture, along with mild cytotoxicity. To be noted that at the protein level, erastin induced a ~10% decrease in STEAP3 and a 1.5-fold increase in β-globin homo- or hetero-dimers. Ferroptosis markers confirmed erastin activity, with Fsp1 to be downregulated and Slc7a11, ferroportin, and the transferrin receptor upregulated. Importantly, erastin also enhanced apoptotic responses, as indicated by increased levels of active caspase-3 (~40%) and reduced cellular proliferation rate (Ki-67, ~35%), suggesting overlap between ferroptotic and apoptotic pathways. Conclusions: Collectively, these findings indicate that erastin modulates erythroid maturation by repressing Steap3 (Six-transmembrane epithelial antigen of prostate 3) and enhancing Hbb expression, yet its differentiation inducing potential is counterbalanced by concurrent apoptosis activation. Overall, our results support a role of ferroptosis in erythroid maturation by linking iron metabolism, regulated cell death, and erythropoiesis, a fact of pharmacological and therapeutic relevance too.
Papadimitriou-Tsantarliotou et al. (Tue,) studied this question.