School of Biomedical Sciences, The Chinese University of Hong Kong , Shatin, Hong Kong.
J Nat Prod. 2014 Jun 27;77(6):1270-4. doi: 10.1021/np4008798. Epub 2014 Jun 16.
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.
2,3,5,4'-四羟基二苯乙烯-2-O-β-D-葡萄糖苷（1）从何首乌中分离得到，是细胞游离动力学中酪氨酸酶的非竞争性抑制剂；它以剂量依赖的方式降低 Vmax 值。化合物 1 抑制 PKA 诱导的黑色素生成，降低酪氨酸酶及其转录因子小眼畸形相关转录因子的蛋白表达，并降低酪氨酸酶和酪氨酸酶相关蛋白 1（TRP-1）之间的复合物形成。免疫荧光显微镜观察到酪氨酸酶与内质网或溶酶体没有关联，这意味着 1 对酶的成熟过程没有直接影响。1 的抗黑色素生成活性可能是通过对酪氨酸酶的非竞争性抑制、下调黑色素生成蛋白的表达以及减少酪氨酸酶/ TRP-1 复合物的形成来介导的。
