木犀草素抑制NF-κB增敏TRAIL诱导肝癌HepG2细胞凋亡作用的研究

Effect of Luteolin Sensitized Human Live Cancer HepG2 Cells to TRAIL-induced Apoptosis by Inhibiting the Activity of NF-κB

目的 研究木犀草素抑制NF-κB增敏肿瘤坏死因子相关凋亡诱导配体(TRAIL)诱导肝癌细胞HepG2凋亡的作用。方法 体外培养人肝癌HepG2细胞,实验分为空白对照组、木犀草素组、TRAIL组、木犀草素+TRAIL组;采用CCK8法分析细胞存活率;流式细胞术检测细胞凋亡情况和细胞周期;Western Blotting法检测IκBα、p-IκBα和NF-κB p65蛋白表达情况。结果 木犀草素(50μmol/L)、TRAIL(20 ng/mL)以及木犀草素+TRAIL作用于HepG2细胞24 h,细胞的凋亡率分别为(11.67±0.20)%、(6.61±0.15)%和(32.93±0.63)%;流式细胞凋亡和周期检测结果显示木犀草素显著增加细胞凋亡,其中,G_(0)/G_(1)期细胞减少,S期细胞增加;TRAIL组细胞变化无统计学意义;木犀草素+TRAIL组细胞凋亡更甚,其中,G_(0)/G_(1)和G_(2)/M期细胞减少,S期增加,细胞停滞于S期;Western Blotting检测结果显示IκBα、p-IκBα和NF-κB p65蛋白在木犀草素组细胞中表达下降,且在木犀草素+TRAIL组中下降更为明显。结论 20 ng/mL TRAIL对HepG2细胞凋亡无显著影响,50μmol/L亚细胞毒性的木犀草素能够增敏TRAIL对HepG2细胞的凋亡作用,主要作用在S期,其作用机制可能与抑制NF-κB的表达有关。

Objective To study the effect of luteolin sensitized human live cancer HepG2 cells to TRAIL-induced apoptosis by inhibiting the activity of NF-κB.Methods Hep G2 cells were cultured in vitro and divided into four groups:control group,luteolin group,TRAIL group and luteolin + TRAIL group.Cell survival rate was analyzed by CCK8 method.Cell apoptosis and cell cycle were detected by flow cytometry.The expressions of IκBα,p-IκBα and NF-κB p65 were detected by Western Blotting method.Results The apoptosis rates of HepG2 cells treated with luteolin(50 μmol/L),TRAIL(20 ng/mL) and luteolin + TRAIL for 24 h were(11.67 ± 0.20)%,(6.61 ± 0.15)% and(32.93 ± 0.63)%,respectively.Flow cytometry showed that luteolin significantly increased cell apoptosis,and the number of cells in G0/G1 phase decreased,while the number of cells in S phase increased.There was no significant difference in cell changes in TRAIL group.In the luteolin + TRAIL group,the cell apoptosis was more severe,and the number of cells in G0/G1and G2/M phase was decreased,the number of cells in S phase was increased,and the cells were stagnated in S phase.The results of Western Blotting detection showed that the expressions of IκBα,p-IκBα and NF-κB p65 protein decreased in luteolin group,and the decrease was more significant in luteolin + TRAIL group.Conclusion 20 ng/mL TRAIL has no significant effect on apoptosis of HepG2 cells.Luteolin with subcytotoxicity of 50 μmol/L sensitivities TRAIL on apoptosis of HepG2 cells,mainly in S phase.The mechanism may be related to the inhibition of NF-κB expression.