Abstract

The objectives of this study were to investigatethe use of palm tocotrienol rich fraction (TRF) and otherwhitening agents to inhibit tyrosinase protein expression,and to determine the efficacy of TRF on UVB-inducedmelanogenesis. Our results indicated that treatment ofB16 melanoma cells with TRF and its acetate, but notalpha-tocopherol (aTP), resulted in a strong in vitro and invivo suppression of tyrosinase protein expression andactivity, as evidenced from the lower pigmentation incell pellets and xenografted tumours. The antimelanogenesiseffect of TRF may be mediated throughmultiple signalling pathways leading to the downregulation of tyrosinase protein expression.