EFFECT OF ARBUTIN ON MELANOGENIC PROTEINS IN HUMAN MELANOCYTES

The inhibitory effect of arbutin, a naturally occurring beta-D-glucopy ranoside derivative of hydroquinone, on melanogenesis was studied bioc hemically by using human melanocytes in culture. Cells were cultured i n the presence of different concentrations of arbutin. The maximum con centration of arbutin that was not inhibitory to growth of the cells w as 100 mu g/ml. At that concentration, melanin synthesis was inhibited significantly by similar to 20% after 5 days, compared with untreated cells. This phenotypic change was associated with the inhibition of t yrosinase and DHICA polymerase activities, and the degree of inhibitio n was dose dependent. No significant difference in DOPAchrome tautomer ase (DT) activity was observed before or after arbutin treatment. West ern blotting experiments revealed there were no changes in protein con tent or in molecular size of tyrosinase, TRP-1 or TRP-2, indicating th at inhibition of tyrosinase activity by arbutin might be due to effect s at the post-translational level.