Mechanistic Insights into Tyrosinase-Catalyzed Metabolism of Hydroquinone: Implications for the Etiology of Exogenous Ochronosis and Cytotoxicity to Melanocytes

Hydroquinone is a common ingredient in skin-lightening products that works through enzyme-mediated chemical reactions. This research revealed how an enzyme called tyrosinase processes hydroquinone through different chemical pathways, ultimately producing melanin-like compounds. The study found that long-term hydroquinone use may cause a darkening side effect called exogenous ochronosis through continued enzyme activity, and identified a new chemical marker to track this process.