Berk, B.; Zhang, J.; Hsu, C.

Ferroptosis, an iron-dependent form of cell death, plays a key role in various diseases, but its impact on immune cells, particularly macrophages, remains unclear. This study explores how macrophage activation influences susceptibility to ferroptosis, focusing on lipopolysaccharide (LPS) and other inflammatory signals. We found that LPS priming enhanced resistance to ferroptosis in bone marrow-derived macrophages (BMDMs), as shown by reduced morphological changes, lower LDH release, and diminished cell death in real-time assays. Similar effects were observed with Zymosan A and TNF-. Importantly, LPS-induced ferroptosis resistance was independent of stress response pathways like Nrf2 signaling. Instead, lipid droplet accumulation, driven by LPS, was central to this resistance. PDE10A inhibition reversed LPS-induced ferroptosis and reduced lipid droplet formation. LPS did not confer similar resistance in non-macrophage cell types, underscoring the macrophage-specific nature of this response. These findings highlight potential therapeutic targets for inflammatory diseases.