Department of Pharmacology, Anhui Medical University, Hefei, Anhui, China.
J Gastroenterol Hepatol. 2010 Feb;25(2):420-6. doi: 10.1111/j.1440-1746.2009.05981.x. Epub 2009 Sep 27.
Compound Astragalus and Salvia miltiorrhiza extract (CASE) is made up of astragalosides, astragalus polysaccharide and salvianolic acids extracted from Astragalus membranaceus Bunge (Leguminosae) and Salvia miltiorhiza Bunge (Lamiaceae) with a standard ratio. Previous reports showed that CASE inhibited hepatic fibrosis by mediating transforming growth factor (TGF)-beta/Smad signaling. This study further investigated the effect of CASE on hepatoma HepG2 cells stimulated by TGF-beta(1) and its potential action mechanisms by TGF-beta/Smad signaling.
Cell proliferation was studied by MTT assay and cell invasion was evaluated by measuring cell migration through Matrigel. Protein expression in hepatoma HepG2 cells stimulated by TGF-beta(1) was analyzed by western blotting and plasminogen activator inhibitor type 1 (PAI-1) transcriptional activity in HepG2 cells was evaluated.
CASE (40 microg/mL) markedly suppressed cell invasion triggered by TGF-beta(1). Smad3 phosphorylation at the linker region (pSmad3L) and Samd2 phosphorylation at the C-terminal region (pSmad2C) were significantly reduced by CASE. Mild elevated Smad3 phosphorylation at C-terminal (pSmade3C) region was enhanced by CASE at 20 microg/mL. In addition, treatment of CASE decreased the level of Smad2/3/4 complex at 80 microg/mL, but upregulated the expression of Smad7 in a dose-dependent manner. CASE also showed inhibitory effect on PAI-1 transcriptional activity.
All these results suggest that CASE exerts anti-HepG2 cell invasion effect by modulating TGF-beta/Smad signaling.
复方黄芪丹参提取物（CASE）由黄芪甲苷、黄芪多糖和丹参酸提取自膜荚黄芪（豆科）和丹参（唇形科），以标准比例混合而成。先前的报告表明，CASE 通过介导转化生长因子（TGF）-β/Smad 信号转导抑制肝纤维化。本研究进一步通过 TGF-β/Smad 信号转导研究了 CASE 对 TGF-β（1）刺激的肝癌 HepG2 细胞的作用及其潜在作用机制。
通过 MTT 测定法研究细胞增殖，通过测量穿过 Matrigel 的细胞迁移来评估细胞侵袭。通过 Western blot 分析 TGF-β（1）刺激的肝癌 HepG2 细胞中的蛋白表达，并评估 HepG2 细胞中纤溶酶原激活物抑制剂 1（PAI-1）的转录活性。
CASE（40μg/ml）显著抑制 TGF-β（1）触发的细胞侵袭。CASE 显著降低连接区磷酸化的 Smad3（pSmad3L）和 C 端磷酸化的 Smad2（pSmad2C）。CASE 在 20μg/ml 时轻度增强 C 端磷酸化的 Smad3（pSmad3C）区域。此外，CASE 处理使 80μg/ml 时 Smad2/3/4 复合物水平降低，但以剂量依赖的方式上调 Smad7 的表达。CASE 还显示对 PAI-1 转录活性的抑制作用。
所有这些结果表明，CASE 通过调节 TGF-β/Smad 信号转导发挥抗 HepG2 细胞侵袭作用。
