Figure 5. Effect of jineol on the levels of melanogenesis-related mRNA and proteins in melan-a cells.
(A) Cells (5 × 105 cells/ml) were cultured for 24 h, and the medium was then replaced with fresh medium containing the indicated concentrations of jineol or arbutin for 24 h. mRNA was extracted using TRIzol and mRNA expressions was analyzed by RT PCR. (B) Cells (1 × 105 cells/ml) were cultured for 24 h; medium was replaced with fresh medium containing the indicated concentrations of jineol or arbutin for 3 days. Total cell lysates were extracted and assayed by western blotting using antibodies against tyrosinase, TYRP-1, TYRP-2, and MITF. Equal protein loadings were confirmed using β-actin. Arb: Arbutin. (C) Statistical analysis of the band intensity of tyrosinase, TYRP-1, TYRP-2, and MITF obtained by western blot analysis. *P < 0.05, **P < 0.01, versus non-treated controls, Student’s t-test. (D) Cells (1 × 105 cells/ml) were cultured for 24 h; the medium was replaced with fresh medium containing the indicated concentrations of jineol for the indicated time interval. Total cell lysates were extracted and assayed by western blotting using antibodies against tyrosinase, and MITF. Equal protein loadings were confirmed using β-actin.