小鼠腹腔巨噬细胞凋亡时线粒体的改变及其调控

MITOCHONDRIAL CHANGES AND THEIR REGULATION INMURINE APOPTOTIC PERITONEAL MACROPHAGE

目的 研究小鼠腹腔巨噬细胞凋亡过程中线粒体和磷酸烟酰胺腺嘌呤 (NADPH)氧化酶活性的变化以及信使分子对线粒体膜电位、细胞内活性氧 (reactive oxygen species,ROS)和凋亡的影响。 方法 激光扫描共聚焦显微术、流式细胞术和荧光标记技术等。 结果 1.地塞米松诱导巨噬细胞快速凋亡 ;2 .线粒体膜电位快速去极化 ,NADPH氧化酶活性剧降 ,ROS快速减少 ,ROS清除剂促进凋亡 ;3.蛋白激酶 C(protein kinase C,PKC)促进凋亡、ROS急剧减少、线粒体膜去极化 ;环腺苷酸 (c AMP)抑制凋亡、ROS急剧减少、线粒体膜去极化 ;环鸟苷酸(c GMP)、酪氨酸蛋白激酶 (TPK)略抑制凋亡 ,不影响 ROS变化 ,但影响线粒体膜去极化。 结论 1.地塞米松处理使线粒体内 NADPH氧化酶活性剧降 ,生成 ROS迅速减少从而促进巨噬细胞凋亡 ;2 .信使分子影响线粒体生成ROS的变化以及线粒体膜去极化从而影响巨噬细胞凋亡。提示线粒体变化 ,尤其是 ROS和膜电位的变化影响巨噬细胞凋亡。

Objective To study the changes in activity of NADPH oxidase, the effects of signal molecules on membrane potential and ROS production of mitochondria in apoptotic murine peritoneal macrophages. Methods Laser scanning confocal microscopy, flow cytometry and fluorescence labeling were used. Results 1 The macrophages treated with dexamethasone developed apoptosis quickly and presented concomitant apoptotic changes. 2 Mitochondria membrane depolarized quickly, the activity of NADPH oxidase declined sharply, and ROS production decreased rapidly. The erasers of ROS promoted macrophage apoptosis. 3 PKC favored, and cAMP inhibited the macrophage apoptosis and the rapid drop in ROS and mitochondrial membrane depolarization. cGMP and TPK which slightly inhibited macrophage apoptosis, had no effects on ROS. Conclusion 1 The activity of NADPH oxidase declined sharply, hence the ROS decreased rapidly, which promoted apoptosis in macrophages treated with dexamethasone. 2 The signal molecules affected apoptosis by modulating ROS decline and mitochondria depolarization. The results suggested that, mitochondria variations, especially the variations of ROS and membrane potential, mainly affected macrophage apoptosis.;