Cytotoxicity of Four Skin Lighteners on Skin Melanoma Cells

Objective To investigate the cytotoxicity of four skin lighteners, such as arbutin, kojic acid derivatives, BL - 99 and hydroquinone dipropionate on murine melenoma cells. Methods Affter B - 16 murine melanoma cells were treated with BL-99 and kojic acid derivatives in contents of 0.5, 1.0, 5.0, 10.0 and 50.0 μg/mL, arbutin in contents of 10, 30, 50, 70 and 100 μg/mL, hydroquinone dipropionate in contents of 0.1, 0.5, 1.0, 5.0 and 10.0 μ3g/mL, respectively, for three days, trypan blue exclusion test was used to determine the cell growth, pyruvic acid colorimetry was used to determine the release of cytoplasmic enzyme (Lactate dehy-drogenase, LDH). Results After treated with the four skin lighteners, the total number of cells decreased and the inhibitory rate of cell proliferation increased significantly. The release of LDH increased significantly after treated with arbutin, kojic acid derivatives and BL - 99. Hydroquinone dipropionate at low concentration (0.1-0.5μg/mL) led a higher LDH release compared with control group, but that at high concentration (1 - 10 μg/ mL) the release had a downward trend. Conclusion The four skin lighteners induce cytotoxicity on B - 16 murine melanoma cells and inhibit the melanoma cell's proliferation obviously. The suggested dose of arbutin, kojic acid derivatives, and BL - 99 for skin lightening is less than 70 μg/mL, 50 μg/mL, 10 μg/mL, respectively, and hydroquinone dipropionate should not be used for lightening cosmetics and /or drugs, or the dose should be limited strictly.