Ginsenosides Rb1 and Rg1 Stimulate Melanogenesis in Human Epidermal Melanocytes via PKA/CREB/MITF Signaling
Figure 1
Ginsenosides Rb1 and Rg1 increased melanin content and tyrosinase activity in melanocytes. The cells were exposed to various concentrations of ginsenoside Rb1 or Rg1 or 10 μM forskolin (FK, used as a positive control) or 10 μM FK + 100 μM Rb1 or 10 μM FK + 300 μM Rg1 for 72 hrs. Cell viability was determined by MTT assay ((a), (d)). The cellular melanin content ((b), (e)) and the cellular tyrosinase activity ((c), (f)) were shown as percentages of vehicle control. Cell pellets after treatment with 300 μM Rg1, 100 μM Rb1, 10 μM FK, 10 μM FK + 100 μM Rb1, or 10 μM FK + 300 μM Rg1 were shown in (g). Data are expressed as the mean ± SD from three independent experiments that were carried out in triplicate. , , as compared with vehicle control (determined by one-way ANOVA). These experiments were conducted with melanocytes cultured from three different donors.
