Objectives: The aim of this study was to identify a novel skin-depigmenting agent from synthetic 1,3-thiazine derivatives.
Methods: We investigated the inhibitory effects of six kinds of 1,3-thiazine derivative on melanogenesis by examining their effects on tyrosinase activity and melanin biosynthesis in melan-a cells and the zebrafish model.
Key findings: Of the six compounds, 4-hydroxy-2,6-dimethyl-5,6-dihydro-4H-1,3-thiazine (TZ-6) had the strongest anti-melanogenic effects in cultured melan-a cells (30.4% inhibition at 100 microm). In addition, TZ-6 exhibited an inhibitory effect on mushroom and cellular tyrosinase. Based on the results of Western blotting, TZ-6 reduced the expression of tyrosinase at 100 microm. Additionally, TZ-6 reduced body pigmentation and inhibited tyrosinase activity in the zebrafish model.
Conclusions: The results have provided useful information for the development of a skin whitening agent.