Stimulation of melanogenesis by scoparone in B16 melanoma cells

Abstract

Aim: The effect of coumarin derivatives on melanogenesis was investigated in B16 murine melanoma cells. Methods: Melanin content and tyrosinase activity were analyzed spectrophotometrically. The expression of tyrosinase, tyrosinaserelated protein-1 (TRP-1) and tyrosinase-related protein-2 (TRP-2) were measured either by reverse transcription-polymerase chain reaction (RT-PCR) or Western blot. Results: Among the coumarin derivatives studied, scoparone (6,7-dimethoxycoumarin) was the most potent; the 6-or 7-methoxy group was found to be essential for the stimulation of melanogenesis. The melanin content was greatly increased by scoparone in a dose-dependent manner; there was no cytotoxicity at the effective concentrations. Scoparone increased enzyme activity as well as protein and mRNA expression of tyrosinase. In addition, mRNA of TRP-1 and TRP-2 were also increased after treatment with scoparone. H-89, an inhibitor of protein kinase A (PKA), completely inhibited the scoparone-induced increase of melanogenesis and the tyrosinase protein. Conclusion: These results suggest that scoparone-induced stimulation of melanogenesis is likely to occur at the transcriptional level of melanogenesis-related enzymes through PKA signaling.

Involvement of Extracellular Signal-Regulated Kinase in Nobiletin-Induced Melanogenesis in Murine B16/F10 Melanoma Cells

“…5,6) Recently, it has been reported that quercetin extracted from herbs, naringenin isolated from citrus, and scoparone from plants stimulate melanogenesis, suggesting that these substances can be used as tanning agents. [7][8][9] In this study, we attempted to identify flavonoids affecting melanogenesis from nobiletin-rich citrus plants native to Jeju island, South Korea. 10) First we examined the effects of the polymethoxylated flavones nobiletin, tangeretin, and sinensetin on melanogenesis (Fig.…”

Effect of xanthohumol on melanogenesis in B16 melanoma cells

“…The melanin content of the cultured B16 cells were measured as described previously (Yang et al, 2006). The cells were washed twice with PBS and lysed with 20 mM Tris-0.1% Triton X-100 (pH 7.5).…”

Inhibitory Effect of [6]-Gingerol on Melanogenesis in B16F10 Melanoma Cells and a Possible Mechanism of Action

“…Cellular tyrosinase activity was determined as described previously, 21) with slight modifications. Briefly, the cells were treated with -MSH (100 nM) for 24 h, and then intracellular tyrosinase activity was measured after treatment with various concentrations of [6]-gingerol (0-100 mM) or kojic acid (200 mM) for 24 h. After these treatments, the cells were washed twice with phosphate-buffered saline and homogenized with 50 mM PBS (pH 7.5) buffer containing 1.0% Triton X-100 and 0.1 mM PMSF.…”