喜树碱诱导Jurkat细胞线粒体膜电势和线粒体质量变化的研究

目的： 研究喜树碱（camptothecin，CPT）诱导Jurkat细胞凋亡过程中线粒体膜电势和线粒体质量的变化。 方法： 用喜树碱处理Jurkat细胞，利用Annexin V-FITC/PI双染流式细胞术研究细胞早期凋亡, PI染色流式细胞术测细胞周期, Annexin V-PE/DiOC6(3) 双染流式细胞术检测线粒体膜电势（△ψm），NAO染色流式细胞术检测线粒体质量。 结果： 在10 μmol·L-1 CPT诱导下，6 h 时Jurkat 细胞早期凋亡的细胞比率（22.59±1.04）%显著高于对照组（3.93±0.73）%（P<0.01）。CPT组坏死比率（2.48±0.53）%与对照组（2.78±0.63）%无显著差异（P>0.05）；并可使细胞出现明显的凋亡峰。晚期凋亡的细胞比率为（13.58±0.97）%显著高于对照组（3.18±0.51）%（P<0.01），CPT组G0/G1期细胞比率（48.14±0.96）% ，明显高于对照组（44.09±0.43）%（P<0.01）。CPT组线粒体发生明显去极化现象，AnnexinV+DiOC6(3)-的细胞比率为（19.47±0.69）%，而对照组比率为（4.21±0.40）%，差异显著（P<0.01）。同时，CPT组线粒体质量显著低于对照组：CPT组NAO+细胞比率为（74.77±1.66）%，对照组为（92.24±1.41）%（P<0.01）。 结论： CPT诱导Jurkat细胞凋亡过程中线粒体去极化作用增强并且线粒体质量下降，表明该凋亡过程与线粒体途径密切相关。

Changes of mitochondrial membrane potential and mitochondrial mass in camptothecin-induced Jurkat cells

AIM: To study the changes of mitochondrial membrane potential (△ψm) and mitochondrial mass in apoptosis of Jurkat cells induced by camptothecin (CPT). METHODS: Jurkat cells were treated with CPT. Annexin V-FITC/propidium iodine (PI) double stainig was used to detected early stage of apoptosis and PI staining for analyzing the cell cycle. Jurkat cells were stained by annexin V-PE/DiOC6(3) to detect changes of △ψm. The mitochondrial mass was measured by cytometry with NAO staining. RESULTS: 6 h after treated with 10 μmol/L CPT, the rate of early apoptotic cells (22.59±1.04)% had significantly difference compared with control group (3.93±0.73)% (P<0.01). The necrotic rate (2.48±0.53)% had no significant difference to that in control group (2.78±0.63)% (P>0.05). Apoptotic peak appeared obviously after treated with CPT, the percentage of late apoptotic cells (13.58±0.97)% had distinctly difference compared with control group (3.18±0.51)% (P<0.01). The cells in G0/G1 phase (48.14±0.96)% were much higher than that in control group (44.09±0.43)% (P<0.01). Mitochondrial depolarization was very obviously in CPT group. The percentage of annexin V+DiOC6 (3)- cells was (19.47±0.69)%, while in control group, was (4.21±0.40)% (P<0.01). Mitochondrial mass in CPT group was significantly lower than that in control group, the percentage of NAO+ cells (74.77±1.66) % had significantly difference compared with control group (92.24±1.41)% (P<0.01). CONCLUSION: During the process of CPT-induced apoptosis in Jurkat cells, mitochondrial depolarization was very obviously and mitochondrial mass decreased, indicating that the process of apoptosis is nearly related to the mitochondrial pathway.