Tanshinone IIA inhibits H2O2-induced ferroptosis in melanocytes through activating Nrf2 signaling pathway

Introduction: Melanocyte ferroptosis has been proven to contribute to the development of vitiligo. Tanshinone IIA (TSA), a Chinese herbal extract, has been shown to inhibit vitiligo progression. Whether TSA regulates ferroptosis in melanocytes remains unclear. Methods: Hydrogen peroxide (H₂O₂) was used to induce melanocytes to stimulate vitiligo cell model in vitro. Cell proliferation was examined by 5-ethynyl-2′-deoxyuridine assay. The levels of malondialdehyde, reactive oxygen species, glutathione peroxidase, and iron were detected by corresponding commercial kit. The protein levels of ferroptosis-related markers and Nrf2 pathway-related markers were examined using western blot and immunofluorescence staining. Cell viability and cytotoxicity were analyzed using Cell Counting Kit-8 assay and lactate dehydrogenase detection. Mitochondrial morphology was examined using a transmission electron microscope. Results: After H₂O₂ treatment, melanocyte proliferation was reduced, while oxidative stress and ferroptosis were enhanced. TSA treatment could inhibit ferroptosis in H₂O₂-induced melanocytes. Besides, TSA could activate Nrf2 pathway and promote Nrf2 nuclear translocation, and Nrf2-specific inhibitor (ML385) also reversed the inhibitory effect of TSA on H₂O₂-induced melanocyte ferroptosis. Conclusion: Our data showed that TSA alleviated H₂O₂-induced melanocyte ferroptosis via activating Nrf2 pathway.