二氢杨梅素促进胶质瘤U251细胞凋亡的实验研究

Experimental study of Dihydromyricetin promoting apoptosis of glioma U251 cells

目的探讨二氢杨梅素(Dihydromyricetin,DHM)对人胶质瘤U251细胞凋亡的促进作用及其机制。方法将体外培养的胶质瘤U251细胞分为对照组和DHM组(根据DHM水平的不同分为3个亚组),MTT法观察细胞活性,Hoechst 33258核染色法观察细胞凋亡,流式细胞仪检测细胞凋亡率,透射电镜观察细胞形态,Western blot检测Bax和bcl-2蛋白表达水平。结果 Hoechst 33258核染色和流式细胞仪检测显示,随着DHM水平的增高,U251细胞凋亡率呈剂量依赖性增高;电镜观察显示,对照组胶质瘤U251细胞形态正常,DHM组胶质瘤U251细胞肿胀,细胞器呈碎片样分散,随着DHM水平升高,线粒体、内质网等细胞器结构破坏明显。此外, DHM处理后Bax蛋白表达水平增高,Bcl-2蛋白表达水平降低。结论 DHM可能通过改变Bax及Bcl-2蛋白表达水平来抑制胶质瘤U251细胞增殖并促进其凋亡。

Objective To study the promote apoptosis effect of dihydromyricetin(DHM) on glioma U251 cells and its mechanism.Methods The glioma U251 cells cultured in vitro were divided into control group and DHM group(divided into three subgroup according to the different concentration of DHM), cell activity was observed by MTT method, cell apoptosis was observed by Hoechst 33258 nuclear staining method, apoptosis rate was measured by flow cytometry, cell morphology was observed by transmission electron microscopy, Bax and bcl-2 protein expressive levels were detected by Western blot.Results The flow cytometry and Hoechst 33258 nuclear staining showed that with the increase of DHM concentration, the apoptosis rate of U251 cells increased in a dose-dependent manner. The electron microscopy showed that the morphology of glioma U251 cells in the control group was normal, the glioma U251 cells in the DHM group were swollen, the organelles were scattered like fragments, with the increase of the concentration of DHM, the structure of mitochondria, endoplasmic reticulum and other organelles were destroyed obviously. Besides, after DHM treatment, the expressive level of Bax protein increased and the expressive level of Bcl-2 protein decreased.Conclusion Dihydromyricetin could inhibite glioma cell’s proliferation and promote glioma cell’s apoptosis by changing the expressive levels of Bax protein and Bcl-2 protein.