Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 151-742, Korea.
Arch Pharm Res. 2012 Mar;35(4):717-22. doi: 10.1007/s12272-012-0416-0. Epub 2012 May 3.
Ginsenosides are active compounds isolated from Panax ginseng Meyer. Among these ginsenosides, less polar ginsenosides such as ginsenoside Rg3 and ginsenoside Rh2 have been demonstrated to have tumor inhibitory effects because of their cytotoxicity. In this study, we evaluated the apoptotic effects of ginsenoside Rk1 in SK-MEL-2 human melanoma. Ginsenoside Rk1 isolated from red ginseng is one of the novel ginsenosides that shows strong cytotoxicity compared to ginsenoside Rg3 in dose- and time-dependent manners. The results of DNA fragmentation, 4',6-diamidino-2-phenylindole staining, and flow cytometric analysis are corroborated that ginsenoside Rk1 induced apoptosis in SK-MEL-2 cells. Western blot analysis revealed up-regulation of Fas, FasL, and Bax protein expression and down-regulation of procaspase-8, procaspase-3, mutant p53 and Bcl-2 protein expression. These findings suggest that ginsenoside Rk1 might be a promising compound to induce apoptosis through both extrinsic and intrinsic pathways in SK-MEL-2 cells.
人参皂苷是从人参 Panax ginseng Meyer 中分离得到的活性化合物。在这些人参皂苷中，极性较小的人参皂苷如人参皂苷 Rg3 和人参皂苷 Rh2 已被证明具有肿瘤抑制作用，因为它们具有细胞毒性。在这项研究中，我们评估了人参皂苷 Rk1 对 SK-MEL-2 人黑色素瘤的凋亡作用。人参皂苷 Rk1 是从红参中分离出来的一种新型人参皂苷，与人参皂苷 Rg3 相比，它在剂量和时间依赖性方面表现出更强的细胞毒性。DNA 片段化、4'，6-二脒基-2-苯基吲哚染色和流式细胞术分析的结果证实，人参皂苷 Rk1 诱导了 SK-MEL-2 细胞的凋亡。Western blot 分析显示 Fas、FasL 和 Bax 蛋白表达上调，而 procaspase-8、procaspase-3、突变型 p53 和 Bcl-2 蛋白表达下调。这些发现表明，人参皂苷 Rk1 可能是一种有前途的化合物，可以通过 SK-MEL-2 细胞中的外在和内在途径诱导细胞凋亡。
