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 (MDA), reactive oxygen species (ROS), glutathione peroxidase (GSH) and iron (Fe2+) 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 (LDH) 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.