title: Tyrosinase inhibitory activity of a glucosylated hydroxystilbene in mouse melan-a melanocytes.
abstract: 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucopyranoside (1), isolated from Polygonum multiflorum, is a noncompetitive inhibitor of tyrosinase in cell-free kinetics; it reduced the Vmax values in a dose-dependent manner. Compound 1 inhibited PKA-induced melanogenesis, reduced the protein expression of tyrosinase and its transcription factor, the microphthalmia-associated transcription factor, and lowered the complex formation between tyrosinase and tyrosinase-related protein 1 (TRP-1). Immunofluorescence microscopy revealed no association of tyrosinase with the endoplasmic reticulum or lysosomes, implying the absence of a direct effect of 1 on the maturation process of the enzyme. The antimelanogenic activity of 1 is likely mediated through a noncompetitive inhibition on tyrosinase, down-regulation of the expression of melanogenic proteins, and reduction of tyrosinase/TRP-1 complex formation.
authors.affiliation: School of Biomedical Sciences, The Chinese University of Hong Kong , Shatin, Hong Kong.
authors.forename: Florence Wing-Ki
authors.initials: FW
authors.lastname: Cheung
authors.forename: Albert Wing-Nang
authors.initials: AW
authors.lastname: Leung
authors.forename: Wing Keung
authors.initials: WK
authors.lastname: Liu
authors.forename: Chun-Tao
authors.initials: CT
authors.lastname: Che
mesh_terms: D000818:Animals; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D008543:Melanins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D010088:Oxidoreductases / Q000378:metabolism; D013267:Stilbenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: C000590846:2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucopyranoside; D005960:Glucosides; D008543:Melanins; D008562:Membrane Glycoproteins; D013267:Stilbenes; D010088:Oxidoreductases; C489799:TYRP1 protein, human; D014442:Monophenol Monooxygenase