MitoQ alleviates H₂O₂-induced mitochondrial dysfunction in keratinocytes through the Nrf2/PINK1 pathway

Oxidative stress plays a critical role in the pathogenesis of vitiligo by damaging keratinocytes, which disrupts their biological functions and influences the progression of the disease. MitoQ, a mitochondria-specific antioxidant, has the potential to prevent disorders associated with oxidative stress and to exert protective effects specifically on mitochondria. This study investigated the protective effects of MitoQ against oxidative stress in keratinocytes. We observed downregulated expression levels of Nrf2, PINK1, Parkin, and LC3 in vitiligo patients. HaCaT cells were treated with 900 μM H₂O₂ and/or 50 nM MitoQ, revealing that MitoQ mitigated the downregulation of Nrf2, PINK1, and Parkin; reduced the nuclear translocation of Nrf2; and decreased the level of mitophagy induced by H₂O₂. Following the knockdown of NFE2L2 or PINK1 in HaCaT cells, we noted an increase in intracellular reactive oxygen species, changes in mitochondrial morphology, a dramatic decrease in the mitochondrial membrane potential, and a significant rise in cell death levels. In comparison to the group without NFE2L2 or PINK1 knockdown, MitoQ treatment failed to alleviate these conditions. These results suggest that MitoQ may regulate the PINK1/Parkin signaling pathway via Nrf2 to counteract mitochondrial oxidative stress induced by H₂O₂ and protect cells from damage. Therefore, our study offers experimental evidence and insights that may inform the development of therapeutic interventions for vitiligo.