Figure 2: (a) Cells showed the increases of melanin after being treated by 15 μg/mL ISL for 48 h in transmission optical images (200x). (b) Effects of ISL on tyrosinase activities in B16F0 cells, , versus control (0 μg/mL). (c) Agarose gel (1.5%) electrophoresis of RT-PCR products showed the effects of ISL on mRNA expression of tyrosinase, TRP-1, and TRP-2 against GADPH. (d) The quantified RT-PCR results in ISL treatments via relative gene expression ratios to GAPDH. Bars represent means ± SD of three independent experiments; , versus control.