Tian Zuo1, Zuo Zhang1, Peng Jiang1, Rui Zhang1, Danni Ni1, Yuan Yuan2, Shaopeng Zhang3. 1. School of Life Science and Technology, Wuhan Polytechnic University, Wuhan, 430023, China. 2. National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China. 3. School of Modern Industry for Selenium Science and Engineering, National R&D Center for Se-Rich Agricultural Products Processing, Wuhan Polytechnic University, Xuefu South Road 68, Changqing Garden, Wuhan, 430023, China. shaopeng@whpu.edu.cn.
Abstract
BACKGROUND: Chikusetsusaponin IV and V (CsIV and CsV), two typical oleanolic acid saponins, are mainly derived from the rhizome of Panax japonicus C.A. Mey. To reveal the anti-cancer effect of CsIV and CsV on liver cancer cells, human hepatic cancer cell lines (HepG2) were exposed to these saponins, and various physiological responses of HepG2 were investigated. METHODS AND RESULTS: HepG2 cells were treated with CsIV, CsV and 5-fluorouracil (5-FU). Cell proliferation was measured by CCK-8 assay. The cell cycle arrest, cell apoptosis and intracellular Ca2+ levels were respectively identified by flow cytometry. The mitochondrial membrane potential was detected by fluorescence microscopy. And, the levels of apoptosis-related proteins were analyzed by western blotting. Both CsIV and CsV were demonstrated to inhibit cell viability, and induce cell cycle arrest and apoptosis of HepG2 in a dose-dependent manner. They also enhanced the intracellular Ca2+ level and decreased the mitochondrial membrane potential in HepG2 cells. Furthermore, p53 and p21 were found up-regulated in HepG2 cells treated by CsIV and CsV. The apoptotic proteins, bax, cytochrome c, cleaved caspase-3/-9, were all found activated in HepG2 cells after CsIV and CsV treatment. The anti-apoptotic protein, bcl-2, was significantly down-regulated in all treated HepG2 cells. CONCLUSION: Our data demonstrated that CsIV and CsV exerted significant cytotoxic effects on HepG2 cells without affecting normal liver cells. And, these chikusetsusaponins, especially for CsIV, showed a potent effect on promoting cell apoptosis in HepG2 cells, which was associated with the activation of p53-mediated apoptosis pathway.
BACKGROUND: Chikusetsusaponin IV and V (CsIV and CsV), two typical oleanolic acid saponins, are mainly derived from the rhizome of Panax japonicus C.A. Mey. To reveal the anti-cancer effect of CsIV and CsV on liver cancer cells, human hepatic cancer cell lines (HepG2) were exposed to these saponins, and various physiological responses of HepG2 were investigated. METHODS AND RESULTS: HepG2 cells were treated with CsIV, CsV and 5-fluorouracil (5-FU). Cell proliferation was measured by CCK-8 assay. The cell cycle arrest, cell apoptosis and intracellular Ca2+ levels were respectively identified by flow cytometry. The mitochondrial membrane potential was detected by fluorescence microscopy. And, the levels of apoptosis-related proteins were analyzed by western blotting. Both CsIV and CsV were demonstrated to inhibit cell viability, and induce cell cycle arrest and apoptosis of HepG2 in a dose-dependent manner. They also enhanced the intracellular Ca2+ level and decreased the mitochondrial membrane potential in HepG2 cells. Furthermore, p53 and p21 were found up-regulated in HepG2 cells treated by CsIV and CsV. The apoptotic proteins, bax, cytochrome c, cleaved caspase-3/-9, were all found activated in HepG2 cells after CsIV and CsV treatment. The anti-apoptotic protein, bcl-2, was significantly down-regulated in all treated HepG2 cells. CONCLUSION: Our data demonstrated that CsIV and CsV exerted significant cytotoxic effects on HepG2 cells without affecting normal liver cells. And, these chikusetsusaponins, especially for CsIV, showed a potent effect on promoting cell apoptosis in HepG2 cells, which was associated with the activation of p53-mediated apoptosis pathway.