摘要
本研究探讨三氧化二砷(As2O3)诱导NB4细胞凋亡过程中线粒体膜电位的改变及环氧合酶-2的表达变化。利用免疫荧光显微镜、DNA电泳等观察As2O3诱导NB4细胞凋亡过程中NB4细胞的形态学改变,流式细胞术检测NB4细胞凋亡率及线粒体膜电位改变,Western blot分析环氧合酶-2的蛋白质表达水平变化。结果表明,经2μmol/L As2O3处理NB4细胞48小时后,荧光显微镜显示NB4细胞出现核致密浓染、染色质固缩及片断化断裂,甚至呈碎片状;提取DNA进行琼脂糖电泳显示典型DNA Ladder现象。流式细胞术分析发现,NB4细胞经3μmol/L As2O3处理48小时后细胞凋亡率为33.34%,As2O3浓度越高,NB4细胞凋亡率越高;以0.5、1、2、4及8μmol/L As2O3分别处理NB4细胞48小时后,线粒体膜电位分别下降12.8%、21.6%、66.9%、83.7%和83.8%;Western blot检测显示,环氧合酶-2在实验组的表达明显低于对照组,且随着As2O3浓度的升高,环氧合酶-2的表达逐渐降低,二者呈显著的负相关关系。结论 :As2O3能够有效诱导NB4细胞凋亡,且在一定浓度范围内具有量效关系;线粒体膜电位下降与As2O3诱导的NB4细胞凋亡有关;环氧合酶-2可能参与了As2O3诱导的NB4细胞凋亡过程。
Objective of this study was to investigate the changes of cyclooxygenase-2 expression and raitochonddal membrane potential in apoptotic NB4 cells induced by arsenic trioxide （ As2O3 ）. The morphological changes in apoptosis process of NIM cells treated by arsenic trioxide were observed under immunofluorescence microscope and DNA electrophoresis method, and the apoptosis rate of NB4 cells and the variations of mitochondrial membrane potential were detected by flow cytometry. Furthermore, the variations of expression level of cyclooxygenase-2 protein were analyzed by using Western blot method. The results indicated that after NB4 cells were treated with 2 μmol/L As2O3 for 48 hours, some variations of NB4 cells were observed, such as pyknosis, chromatin segmentation, even fragmentation. Meanwhile, the typical DNA Ladder phenomenon was observed. The apoptosis rate of NB4 cells treated with 3 μmol/L As2O3 for 48 hours was 33.34%, Furthermore the apoptosis rate of NB4 cells was enhanced along with the increase of concentration of As203. After NB4 cells were treated with 0. 5, 1,2,4 and 8μmol/L As2O3 for 48 hours, the mitochondrial membrane patential decreased by 12. 8%, 21. 6%, 66.9%, 83.7% and 83.8% respectively. The Western blot detection results showed that the expression level of cyclooxygenase-2 protein in NB4 ceils was lower than that in control cells and decreased along with the rise of As203 concentration, then the negative dose-dependent manner was observed between these 2 groups. It is concluded that As2O3 can effectively induce NB4 cell apoptosis, and the dose-dependent manner existed in certain extent of concentrations. The decrease of mitochondrial membrane potential may be related with NIM cell apoptosis induced by As2O3. Cyclooxygenase-2 participates in the process of NB4 cell apoptosis induced by As2O3.
出处
《中国实验血液学杂志》
CAS
CSCD
2011年第3期648-651,共4页
Journal of Experimental Hematology
基金
军队留学归国人员启动基金资助课题
编号071025
