Effects Of Glossy Privet Fruit On The Tyrosinase Activity And Melanogenesis Of Cultured Human Melanocytes

Objective To study the effects of tyrosol and oleanolic acid on the proliferation, tyrosinase activity and melanogenesis of cultured humanmelanocytes, and to explore the biomolecular mechanism of their effects. Methods After treatment of melanocytes with those substances for 72h, MTT assay was applied to determine cell proliferation, the tyrosinase activity was detected by dopa oxidase assay, the melanin content was measured by NaOH-assay, and the mRNA level of tyrosinase(TYR) and tyrosinase related protein-1(TRP-1) was detected by RT-PCR.Results The addition of tyrosol to cultured human melanocytes significantly stimulated tyrosinase activity and melanogenesis in a dose dependant manner, and reverse transcription-polymerase chain reaction of RNA isolated from melanocytes exposed to tyrosol revealed an upregulation of mRNA transcripts for TYR and TRP-1 for about 39.10% and 99.26% respectively; oleanolic acid also could increase tyrosinase activity and melanogenesis, and compared with its control, the mRNA level of TYR and TRP-1 increased 31.88% and 17.73% respectively; as far as glossy privet fruit was concerned, it could promote cell proliferation and melanogenesis of melanocytes; and it could upregulate the mRNA level of TYR and TRP-1 for about 10.11% and 126%.Conclusion These results suggest that tyrosol and oleanolic acid may stimulate tyrosinase activity and melanogenesis of cultured human...