Lapointe J, Bergeron D, Dufour M, Dubé D, Govindan M V, Lambert R D
Department of Ontogeny & Reproduction, CHUL Research Center, Ste-Foy, Quebec, Canada.
Cell Prolif. 1993 Mar;26(2):125-38. doi: 10.1111/j.1365-2184.1993.tb00013.x.
Rabbit embryo-fetal fluid (EFF) contains regulatory factors of cell proliferation which increase the duration of the cell cycle, induce a quiescent status in some cells and lead up to cell death in others. The objective of this study was to demonstrate which of the two processes, namely necrosis or apoptosis, was responsible for the cell death. Inhibitors of protein synthesis, and nuclease and phospholipase A2 activities did not restore the viability of the cells treated with EFF. Using a combination of DNA labelling and extraction, it was possible to show that a large proportion of DNA was fragmented in the cells released in the supernatant while only a very small portion of DNA was fragmented in the monolayer cells. EFF did not induce fragmentation of DNA into nucleosome-sized subunits as analysed using polyacrylamide gel electrophoresis. Nevertheless, using cytofluorometric analysis, it was possible to demonstrate that 50% of the cells released in the supernatant contained a lower quantity of DNA per cell than in the control cells. This was also observed with EFF-treated monolayer cells but not in the control monolayer cells. The reduction of the DNA content per monolayer cell became significant at 48 h of treatment with EFF. Electron microscopic analysis did not reveal blebbing of the cells. However, depletion of glycogen, condensation of mitochondria and increasing number of lysosomes and residual bodies were observed upon treatment with EFF. From these experiments we conclude that the DU-145 cells treated with EFF do not die by apoptosis, but rather seem to die by necrosis.
兔胚胎 - 胎儿液（EFF）含有细胞增殖调节因子，这些因子会延长细胞周期的持续时间，在某些细胞中诱导静止状态，并导致其他一些细胞死亡。本研究的目的是证明细胞死亡是由坏死还是凋亡这两个过程中的哪一个引起的。蛋白质合成抑制剂、核酸酶和磷脂酶A2活性的抑制剂均不能恢复用EFF处理的细胞的活力。通过结合DNA标记和提取，有可能表明上清液中释放的细胞中有很大一部分DNA发生了片段化，而单层细胞中只有非常小一部分DNA发生了片段化。如使用聚丙烯酰胺凝胶电泳分析所示，EFF不会诱导DNA断裂成核小体大小的亚基。然而，通过细胞荧光分析，可以证明上清液中释放的50%的细胞每个细胞所含的DNA量低于对照细胞。在用EFF处理的单层细胞中也观察到了这一现象，但在对照单层细胞中未观察到。在用EFF处理48小时后，每个单层细胞的DNA含量减少变得显著。电子显微镜分析未发现细胞有出泡现象。然而，在用EFF处理后，观察到糖原减少、线粒体凝聚以及溶酶体和残余体数量增加。从这些实验中我们得出结论，用EFF处理的DU - 145细胞不是通过凋亡死亡，而是似乎通过坏死死亡。
