淫羊藿苷抑制正常黑素细胞黑素合成的研究

目的:观察中药单体淫羊藿苷对体外培养的正常黑素细胞黑素合成和酪氨酸酶活性的影响。方法:选择高、中、低3个浓度的中药单体作用于体外培养的黑素细胞,测定细胞酪氨酸酶活性、黑素含量和细胞增殖率。采用间接免疫荧光染色法对药物作用的黑素细胞和对照的酪氨酸酶(tyrosinase熏TYR)、酪氨酸酶相关蛋白-1(tyrosinaserelatedprotein-1熏TRP-1)、TRP-2进行标记,然后采用激光共聚焦显微镜半定量分析淫羊藿苷作用后细胞内3种成分表达量的变化。结果:淫羊藿苷明显抑制酪氨酸酶活性和黑素的生成(P<0.01),且呈浓度依赖性,但淫羊藿苷抑制黑素生成的作用较氢醌弱(P<0.01);淫羊藿苷以浓度依赖的方式促进细胞的增殖,氢醌则抑制了细胞的增殖;淫羊藿苷对黑素细胞内TYR和TRP-2的表达没有明显影响,但是对TRP-1的表达却明显增加了。结论:淫羊藿苷能够抑制黑素合成和酪氨酸酶活性,这种抑制可能主要通过抑制酪氨酸酶活性起作用。

Inhibitory effects of icariin on melanogenesis of human epidermal melanocytes

Objective:To evaluate the influence of icariin on tyrosinase activity and melanogenesis of human epidermal melanocytes.Methods:Different concentrations of icariin and hydroquinone were incubated with melanocytes.Tyrosinase ac-tivity,melanin content and proliferation rate of melanocytes were measured respectively.Indirect immuno-fluorescent staining was used to label the icariin and hydroquinone treated melanocytes,tyrosinase,tyrosinase related protein-1(TRP-1),and tyrosi-nase related protein-2(TRP-2).Laser confocal microscopy was employed to carry out semi-quantitative analysis of the expres-sion of tyrosinase(TYR),TRP-1and TRP-2.Results:The icariin inhibited tyrosinase activity and melanogenesis in a dose-dependent manner(P<0.01).However,the effect of icariin were weaker than that of hydroquinone.The icariin could stimulate the proliferation of human melanocytes,but the hydroquinone showed an opposite effect.Icariin had no effect on the expres-sion of TYR and TRP-2,but increasing the expression of TRP-1.Conclusion:The icariin can inhibit tyrosinase activity and melanogenesis of human epidermal melanocytes.