二氢杨梅素诱导MDA-MB-231细胞凋亡

为了探讨二氢杨梅素(dihydromyricetin,DMY)诱导人乳腺癌MDA-MB-231细胞凋亡的机制,利用倒置显微镜观察细胞形态变化,用流式细胞仪检测DMY对MDA-MB-231细胞的致凋亡能力和细胞内钙离子浓度和线粒体膜电位(ΔΨm)的改变,用蛋白质印迹(Western blotting)分析检测半胱氨酸天冬氨酸蛋白酶-3(caspase-3)和半胱氨酸天冬氨酸蛋白酶-9(caspase-9)的变化。结果表明:MDA-MB-231细胞随DMY质量浓度加大而变圆变小,细胞存活数减少;流式细胞仪检测显示随DMY质量浓度的增加,DMY对MDA-MB-231细胞有促凋亡作用,胞内钙离子浓度逐渐增加,而线粒体跨膜电位(ΔΨm)逐渐减少;Western blotting结果显示DMY可诱导MDA-MB-231细胞中caspase-3和caspase-9蛋白质活化,并呈现浓度依赖关系。表明DMY可通过线粒体途径诱导MDA-MB-231细胞凋亡。

MDA-MB-231 cell apoptosis in vitro induced by dihydromyricetin

To investigate the effect of dihydromyricetin(DMY) induction on MDA-MB-231 cell apoptosis and its mechanism,the changes of cell morphological characteristics were observed under inverted microscope.Apoptosis,intracellular Ca2+ level and the mitochondrial innermembrane potential(ΔΨm) were analyzed by flow cytometry(FCM).Western blotting was employed to detect the expression of caspase-3 and caspase-9.The results showed that the cell size and volume became smaller with increasing concentration of DMY.Increased Sub-G1 peak and intracellular Ca2+ level,as well as the decreased mitochondrial ΔΨm in MDA-MB-231 cells were obviously observed in a dose-dependent manner.Western blotting analysis showed that DMY dose-dependently increased the expression of caspase-3 and caspase-9 in MDA-MB-231 cells.These results indicate that DMY can induce MDA-MB-231 cell apoptosis by the mitochondrial pathway.