苦参碱抑制Akt信号通路诱导结肠癌SW480细胞凋亡

Matrine Induces Apoptosis of Human Colon Cancer Cell Line SW480 by Inhibition of Akt Signaling Pathway

目的:研究苦参碱对人结肠癌SW480细胞的促凋亡作用及其可能的分子机制。方法:噻唑蓝比色法(MTT)测定苦参碱对SW480细胞株增殖的影响;Hoechst33258染色检测苦参碱对SW480细胞凋亡的影响,流式细胞术检测细胞凋亡率;蛋白免疫印迹法(Western blot)检测苦参碱对SW480细胞中总蛋白激酶B(Akt),磷酸化蛋白激酶B(p-Akt),B细胞淋巴瘤-2(Bcl-2),Bcl-2相关X蛋白(Bax)表达的干预作用。结果:苦参碱(0.25,0.5,1.0,1.5,2.0 g·L^(-1))能浓度和时间依赖性地抑制SW480细胞增殖。作用24,48,72 h的半数抑制浓度(IC50)分别为1.72,1.08,0.67 g·L^(-1),Hochest33258染色和流式细胞术结果显示苦参碱能显著诱导细胞凋亡(P<0.01),随着药物质量浓度的提高,细胞凋亡率逐渐上升。Western blot检测显示,SW480细胞加入苦参碱后,胞内总Akt的含量无显著变化,但p-Akt的生成被显著抑制,凋亡抑制性蛋白Bcl-2表达降低,促凋亡蛋白Bax表达增高(P<0.05)。结论:苦参碱能够诱导SW480细胞凋亡,该药理作用可能与苦参碱对Akt信号通路的抑制有关。

Objective ： To investigate the effect of matrine on the apoptosi of human colon cancer cell line SW480, and to explore its underlying mechanism. Method： The effect of matrine on SW480 cell line proliferation was detected by methyhhiazolyldiphenyl-tetrazolium bromide （MTT） assay, its effect on SW480 cell apoptosis was detected by Hoechst33258 staining and flow cytometry was used to determine the apoptosis rate. Protein levels of proteinkinase B （Akt）, p-Akt, B-cell lymphoma-2 （Bcl-2）, and Baxin SW480 cells were detected by Western blot. Result： Matrine （0.25, 0.5, 1.0, 1.5, 2.0 g·L^-1） inhibited SW480 cell proliferation in time and dose- dependent manners. The half maximal inhibitory concentration （ICs0） was 1.72, 1.08, 0. 67 g·L^-1 respectively for 24, 48, 72 h. Hoechst33258 staining and flow cytometry showed that matrine could significantly induce apoptosis of SW480 （P 〈 0.01 ）. The apoptosis rate was gradually increased with the increase of drug concentration. Western blot results showed that after adding matrine in the SW480 cells, the expression levels of p-Akt and Bcl-2 were down-regulated （P 〈 0.05） , while the expression level of Bax was up-regulated and the expression level of total Akt wasn＇t affected. Conclusion： Matrine could induce apoptosis in SW480 cells, which may related to the inhibition of Akt Signaling Pathway and the related downstream targets.