摘要目的 观察黄芪多糖(APS)对肝癌细胞生长增殖的作用及对AMPK信号通路的影响.方法 以200、300、400 mg/L浓度黄芪多糖处理肝癌HepG2细胞后分别培养12、24、48 h,采用MTT法检测细胞抑制率,荧光显微镜下观察细胞凋亡,Western blot法测定细胞总腺苷酸活化蛋白激酶(AMPK)、磷酸化腺苷酸活化蛋白激酶(p-AMPK)、磷酸化的哺乳动物雷帕霉素靶蛋白(p-mTOR)的蛋白表达情况.结果 各种浓度的黄芪多糖对肝癌HepG2细胞增殖均有明显抑制作用(P＜0.05);300 mg/L浓度的黄芪多糖较200 mg/L的黄芪多糖对肝癌HepG2细胞增殖的抑制作用更加显著(P＜0.05);而400 mg/L与300 mg/L的黄芪多糖对肝癌HepG2细胞增殖的抑制作用差异无统计学意义(P＞0.05).荧光显微镜观察发现各种浓度黄芪多糖均可促进肝癌HepG2细胞凋亡(P＜0.05),其中300 mg/L的黄芪多糖较200 mg/L作用显著(P＜0.05);而400 mg/L与300 mg/L的黄芪多糖促进肝癌HepG2细胞凋亡的作用差异无统计学意义(P＞0.05).Western blot结果表明黄芪多糖能够增加p-AMPK的表达(P＜0.05),并抑制其下游p-mTOR蛋白表达(P＜0.05).AMPK阻断剂compound C处理后黄芪多糖抑制肝癌细胞增殖及促进凋亡的作用被阻断.结论 黄芪多糖可抑制肝癌细胞生长增殖并促进凋亡,其机制与AMPK-mTOR信号通路有关.

abstractsObjective To investigate the effect of astragalus polysaccharides (APS) on the growth and proliferation of hepatocellular carcinoma cells and its effect on adenosine monophosphate activated pro-tein kinase (AMPK) activity.Methods Hepatocellular carcinoma HepG2 cells cultured for 12,24,and 48 hours were treated with 200,300,and 400 mg/L concentration of astragalus polysaccharides.The cell inhibition rate was detected with methyl thiazolyl tetrazolium (MTT),and apoptosis was observed under the fluorescence microscope.Western blot method was used to measure the expression of total AMPK,phosphorylated AMPK (p-AMPK),and phosphorylate mammalian target of rapamycin (p-mTOR) protein expressions.Results Astragalus polysaccharides of each concentration significantly inhibited the proliferation of human hepatoma HepG2 cells (P ＜ 0.01),and the effect of 300 mg/L concentration astragalus polysaccharides was more significant than that of the 200 mg/L concentration (P ＜0.01);while inhibitory effect of 400 and 300 mg/L Astragalus polysaccharides on the proliferation of human hepatoma cell line HepG2 was not significant difference.We found that Astragalus polysaccharides of each concentration could promote the apoptosis of HepG2 cells,and the effect of 300 mg/L Astragalus polysaccharides was more significant.However,astragalus polysaccharide of 400 mg/L concentration could promote the apoptosis no more than the 300 mg/L concentration,which was observed by fluorescent microscope.Western blot results showed that astragalus polysaccharides could increase the expression of p-AMPK (P ＜ 0.05),and inhibit its downstream protein expressions of p-mTOR (P ＜ 0.05).The proliferation effect of astragalus polysaccharides was weakened after accession of AMPK antagonist compound C on hepatocellular carcinoma cells.Conclusions APS can inhibit the growth and proliferation of hepatocarcinoma cells,and its mechanism is related to the AMPK-mTOR pathway.