Induction of ferroptosis in human keratinocyte HaCaT cells by squalene hydroperoxide: Possible prevention of skin ferroptosis by botanical extracts

Ever since the proposal of ferroptosis, it has been studied as a nonapoptotic cell death caused by iron ion-dependent phospholipid (PL) peroxidation. We previously showed that treatment of human hepatoma cell line HepG2 with prepared PL hydroperoxide (PLOOH) resulted in ferroptosis. However, in human sebum, the major hydroperoxide is not PLOOH but squalene hydroperoxide (SQOOH), and to our knowledge, it is not established yet whether SQOOH induces ferroptosis in the skin. In this study, we synthesized SQOOH and treated human keratinocyte HaCaT cells with SQOOH. The results showed that SQOOH induces ferroptosis in HaCaT cells in the same way that PLOOH causes ferroptosis in HepG2 cells. Some natural antioxidants (botanical extracts) could inhibit the ferroptosis in both the cell types. Consequently, future research focus would revolve around the involvement of SQOOH-induced ferroptosis in skin pathologies as well as the prevention and treatment of skin diseases through inhibition of ferroptosis by botanical extracts. [Display omitted] •Similar to phospholipid hydroperoxide, squalene hydroperoxide induced ferroptosis.•Squalene hydroperoxide-induced ferroptosis may be involved in skin pathologies.•Some natural antioxidants showed anti-ferroptotic tendencies.•Inhibition of ferroptosis by botanical extracts may prevent skin diseases.