title: Flavonoids, taxifolin and luteolin attenuate cellular melanogenesis despite increasing tyrosinase protein levels.
abstract: Flavonoids are a group of polyphenolic compounds widely distributed in plants. Their potent bio-activities and relatively low toxicity have rendered them useful ingredients in functional cosmetics. The purpose of the present study was to examine their potential effects on cellular melanogenesis. When tested in murine melanoma B16F10 cells activated by alpha-melanocyte stimulating hormone (alpha-MSH), taxifolin and luteolin inhibited the cellular melanogenesis as effectively as arbutin, one of the most widely used hypopigmenting agents in cosmetics. As opposed to their antimelanogenic effects, taxifolin and luteolin rather increased the tyrosinase protein levels in the absence and presence of alpha-MSH. However, these flavonoids effectively inhibited tyrosinase-catalysed oxidation of l-dihydroxyphenylalanine in cell-free extracts and in living cells. Furthermore, they attenuated cell pigmentation induced by expression of exogenous human tyrosinase. Therefore, the antimelanogenic effects of taxifolin and luteolin are attributed to their inhibitory effects on tyrosinase enzymatic activity, despite their effects on increasing tyrosinase protein levels.
authors: Department of Molecular Medicine, Kyungpook National University School of Medicine, 101 Dongindong-2-ga, Junggu, Daegu, 700-422, Republic of Korea.
authors: Sang Mi
authors: SM
authors: An
authors: Hyo Jung
authors: HJ
authors: Kim
authors: Jung-Eun
authors: JE
authors: Kim
authors: Yong Chool
authors: YC
authors: Boo
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D005419:Flavonoids / Q000494:pharmacology*; D047311:Luteolin / Q000494:pharmacology*; D008543:Melanins / Q000096:biosynthesis*; D008546:Melanoma, Experimental / Q000201:enzymology / Q000378:metabolism; D051379:Mice; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D011794:Quercetin / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D005419:Flavonoids; D008543:Melanins; D011794:Quercetin; C003377:taxifolin; D014442:Monophenol Monooxygenase; D047311:Luteolin