ABSTRACT
BACKGROUND AND OBJECTIVE: The biosafety of hydroquinone and its derivatives as skin whitening agent remains controversial. Here, we investigated the effects of hydroquinone, arbutin, and deoxyarbutin (d-arb) on melanogenesis and antioxidation using cultured melan-a melanocytes in the presence or absence of ultraviolet A (UVA)-induced oxidative stress and determined whether d-arb enables to be an alterative to hydroquinone and arbutin for skin whitening use. METHODS: d-arb was synthesized in this study by removing all hydroxyl groups from the glucose side-chain of arbutin. Tyrosinase activity was measured by (14)C-tyrosine incorporation, the intracellular reactive oxygen species (ROS) level was monitored by H(2)DCFDA fluorescence labeling, and the cell viability was determined by MTT assay in murine melan-a melanocytes treated with hydroquinone, arbutin and deoxyarbutin in the presence or absence of UVA-induced oxidative stress. RESULTS: The cytotoxicity of hydroquinone and arbutin except for d-arb was increased while the cells exposed to a nontoxic dose (3J/cm(2)) of UVA irradiation. Suppressed ROS generation was noted by the treatment of d-arb to compare with arbutin and hydroquinone. All three compounds had a similar inhibition on tyrosinase activity in dose-dependent manners with two- to three-fold decreases over the untreated control. There was no change in expression of tyrosinase protein in cells treated with arbutin or hydroquinone, but a decreased protein expression of tyrosinase was seen in deoxyarbutin-treated cells. CONCLUSIONS: Deoxyarbutin exerts potent tyrosinase inhibition, lessened cytotoxicity, and certain antioxidation potential, may serve as an effective and safe alternative to hydroquinone for use in skin whitening.
