Inhibitory effect of [6]-gingerol on melanogenesis in B16F10 melanoma cells and a possible mechanism of action.

[6]-Gingerol is an active component of ginger that shows antipyretic and anti-inflammation activities. To find a novel skin-whitening agent, the melanogeneis inhibitory effects and action mechanisms of [6]-gingerol were investigated. In the present study, the effects of [6]-gingerol on mushroom tyrosinase, tyrosinase activity, and melanin content were determined spectrophotometrically, and the expression of tyrosinase and related proteins in B16F10 murine melanoma cells was evaluated by Western blotting. Furthermore, a possible signaling pathway involved in [6]-gingerolmediated depigmentation was investigated by means of specific inhibitors. The results revealed that [6]-gingerol (25-100 µM) effectively suppresses murine tyrosinase activity and decreases the amount of melanin in a dose-dependent manner. Additionally, it also effectively decreased the intracellular reactive oxygen species (ROS) level in a dose-dependent pattern in the same dose range. Our results indicate that [6]-gingerol inhibits melanogenesis of B16F10 melanoma and can function as a good skinwhitening agent.