Retinoids anti-ferroptosis in human epidermal keratinocytes

Summary: Abstract Body: Dermatology, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China Retinoids, a group of substances exhibiting retinol-like biological activity, primarily include retinol, retinal, and retinoic acid. It has been indicated that retinol and its metabolites, all-trans retinal (atRAL) and all-trans retinoic acid (ATRA), possess anti-ferroptotic effects in both neuronal and non-neuronal cell lines. Increasing evidence suggests that the progression of various skin diseases, such as psoriasis, photosensitive dermatitis, and melanoma, is associated with ferroptosis. Herein, we aimed to investigate whether Retinoids can rescue human keratinocytes from ferroptosis. We established a ferroptosis model in immortalized human keratinocyte HaCaT cells using RSL3 and assessed the anti-ferroptotic effects of seven Retinoids, including all-trans retinal (atRAL), 9-cis retinal (9-cis RAL), 11-cis retinol (11-cis ROL), retinyl palmitate (RP), retinyl acetate (RA), all-trans retinoic acid (ATRA), and all-trans retinol (Vit A). After 24 hours of co-culture, the compounds that exhibited significant anti-ferroptotic effects were further evaluated for their ability to reverse RSL3-induced lipid peroxidation and increased iron levels in HaCaT cells. Lipid peroxidation and iron levels were detected using the Liperfluo probe and FerroOrange probe by flow cytometry. The results showed that the metabolites of retinol, atRAL and ATRA demonstrated a pronounced rescue effect on ferroptosis in immortalized human keratinocyte HaCaT cells. They exerted their anti-ferroptotic effects by reducing lipid peroxidation and lowering intracellular iron concentrations induced by RSL3 in HaCaT cells. Taken together, these findings suggest that atRAL and ATRA may have potential therapeutic implications for skin diseases related to ferroptosis. Peihong Lyu¹, Wen Zeng¹, Wei Zhang¹, Yu Wang¹, Hongguang Lu¹ 1. The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China. Translational Studies: Cell and Molecular Biology