Quercetin Inhibits α‐MSH‐stimulated Melanogenesis in B16F10 Melanoma Cells

Abstract

Quercetin is known to inhibit tyrosinase activity and melanin production in melanocytes. However, several reports suggest that quercetin has different and opposite effects on melanogenesis. This study examined the precise effects of quercetin on melanogenesis using cell-free assay systems and melanocytes. Quercetin inhibited the monophenolase and diphenolase activities of tyrosinase, and melanin synthesis in cell-free assay systems. Quercetin induced mild stimulation of the tyrosinase activity and dihydroxyphenylalaminechrome tautomerase (TRP-2) expression but only at low concentrations (<20 μm) in B16F10 melanoma cells. In contrast, the addition of 50 μm quercetin to the cells led to a significant decrease in the activity and synthesis of tyrosinase, as well as a decrease in the expression of tyrosinase-related protein-1 and TRP-2 proteins, regardless of the presence or absence of α-melanocyte stimulating hormone (α-MSH). Quercetin also reduced the intracellular cAMP and the phosphorylated protein kinase A levels in α-MSH-stimulated B16F10 cells. Moreover, quercetin (20 μm) diminished the expression and activity of tyrosinase, and melanin content in cultured normal human epidermal melanocytes. These effects were not related to its cytotoxic action. Although the in vivo effects of quercetin are still unclear, these results suggest that quercetin could play important roles in controlling melanogenesis.

Aqueous fraction from Cuscuta japonica seed suppresses melanin synthesis through inhibition of the p38 mitogen-activated protein kinase signaling pathway in B16F10 cells

“…It was also reported that quercetin, kaempferol and flavonoids such as compounds found in Semen cuscutae extract have been known to inhibitory effect against tyrosinase activity (Kubo and Kinst-Hori, 1999;Rho et al, 2011;Yang et al, 2011b). In spite of the modern pharmacological studies of Semen cuscutae, the molecular mechanisms of the anti-melanogenic effects have not been elucidated.…”

Effect of quercetin derivatives on melanogenesis stimulation of melanoma cells

“…However, quercetin has been reported to elicit the opposite effect and accelerate melanogenesis in human melanoma cells [71]. Furthermore, it was reported that the direction of its melanogenesis-regulating activity depends on the concentration of quercetin used [72]. A small number of studies have shown that quercetin derivatives can control melanogenesis.…”

Sesamol decreases melanin biosynthesis in melanocyte cells and zebrafish: Possible involvement of MITF via the intracellular cAMP and p38/JNK signalling pathways

“…Melanogenesis is modulated by several factors, including UV irradiation, alpha‐melanocyte‐stimulating hormone ( α ‐MSH) 7, forskolin, stem cell factor (SCF) 8, wnt‐3a 9 and isobutylmethylxanthine (IBMX) 10, within intracellular melanosomes in the melanocytes 11. Stimulation of the melanocortin 1 receptor (MC1R) by α ‐MSH activates adenyl cyclase through G protein signalling, which subsequently increases cyclic adenosine monophosphate (cAMP) production.…”