关键词: 槲芪散, 槲寄生提取物, 细胞周期, 细胞凋亡, 细胞内游离钙离子

Abstract: Objective To probe the inhibitory effect of human hepatocarcinoma cell line HepG2 and the influence of intracellular free Ca²⁺ levels induced by Chinese herbs, Huqi San(HQS) and its principal drug Ramulus Visci Extract. Methods The proliferation of HepG2 were observed by MTT colormetric assay. The cell cycle and the rate of apoptosis of HepG2 were examined by using flow cytometry. The fluorescent intensity of intracellular free Ca²⁺ was observed by laser scanning confocal microscopy.Results Both HQS and Ramulus Visci extract could inhibit the proliferation of HepG2 in a time and dose-dependent manner, the numeric value of OD in high dose group decreased markedly compared to the control group(P<0.001), expect the high dose group of HQS and total Alkaloid of Viscum at the time of 48 h. After treatment with the drugs for 72 h, the cell population in the group of Ramulus Visci Polysaccharides and total Alkaloid of Viscum increased in G1 phase and G2 phase and decreased it in S phase; Comparatively, in the group of HQS, the proportion of the cells in S phase decreased, while cells at G2 phase increased, but there was no a significant change in the G1 phase. In addition, all of the three drugs could induce the apoptosis of HepG2. The results showed with laser scanning confocal microscopy that as different dose of the three drugs were put into the Petri dishes respectively, and we found that the fluorescent intensity did not change obviously when the cells were treated with the low dose drugs. But as we put into three high dose drugs into the Petri, dishes the fluorescent intensity increased instantly and maintained at a high level for periods of time without fluctuating nearly except a little decrease with total alkaloid of Viscum. ConclusionHuqi San, Ramulus Visci Polysaccharides and total alkaloid of Viscum all could inhibit the proliferation of cancer cells and promoted their apoptosis. The calcium overload maybe a possible mechanism of the apoptosis of HepG2 induced by Huqi San and Ramulus Visci Extract.

Key words: Huqi San, Ramulus Visci extract, cell cycle, apoptosis, intracellular free Ca²⁺