Elucidation of the intracellular mechanisms of cisplatin-induced apoptosis in renal cell line

我们研究了顺铂诱导温敏猴病毒40基因转基因小鼠的近端直小管(S_3)细胞系凋亡的细胞内机制。(1)caspase的参与：利用多肽caspase抑制剂和编码caspase抑制剂的病毒基因的引入，caspase-3似乎参与了顺铂诱导的细胞凋亡，而蛋白激酶C抑制剂星形孢子素诱导的细胞凋亡中除caspase-3外，还有其他一些caspase参与。因此，不同的caspase可能参与了不同刺激诱导的S_3细胞的凋亡。通过RT-PCR分析小鼠单个肾单位节段中caspase-3在肾组织中的分布。Caspase-3在所有受试小鼠肾单位节段均有表达，以远端肾小管和集合管表达最高。(2)与细胞周期进程的关系0：抑制caspase可增加G2…的程度顺铂处理的S_3细胞发生更多的细胞周期停滞，提示caspase的激活通过减少顺铂处理的S_3细胞周期的G2期细胞数而诱导细胞凋亡。(3)氧自由基类的参与：用荧光探针和激光共聚焦扫描显微镜检测顺铂处理的S_3细胞产生H_2O_2。过氧化氢酶抑制顺铂诱导的S_3细胞H_2O_2的产生和细胞毒作用。此外，H_2O_2还可诱导S_3细胞发生凋亡、坏死、肿胀和凋亡。由于在H_2O_2处理的S_3细胞中检测到了DNA片段化，DNA片段化似乎并不是细胞凋亡所特有的。(4)癌基因的参与：顺铂诱导的S_3细胞c-fos mHNA表达增加。Bcl2过表达抑制顺铂诱导的S_3细胞Caspase-3活化和细胞死亡结果提示，Caspase、细胞周期、氧自由基和癌基因参与了顺铂诱导的S_3细胞的凋亡。较少

We have examined the intracellular mechanisms of cisplatin-induced apoptosis in mouse terminal proximal straight tubule (S_3) cell line derived from transgenic mice harboring temperature-sensitive simian virus 40 antigen gene. (1) The involvement of caspase : Using the peptide caspase inhibitor and the introduction of viral gene encoding caspase inhibitor, it appears that caspase-3 is involved in cisplatin-induced apoptosis, whereas some caspases other than caspase-3 in apoptosis induced by staurosporine , protein kinase C inhibitor. Thus, different caspases may be involved in apoptosis in S_3 cells induced by different stimuli. The intranephron distribution of caspase-3 was examined by RT-PCR analysis from mRNA of mouse individual nephron segments. Caspase-3 mRNA was expressed in all of mouse nephron segments tested, and those for distal tubule and collecting duct were the highest. (2) The association with cell cycleprogression 0 : The inhibition of caspases increased the degree of G2 … More arrest in cisplatin-treated S_3 cells, suggesting that the activation of caspases induces apoptosis by decreasing the number of cells arrested at G2 phase of the cell cycle in cisplatin-treated S_3 cells. (3) The involvement of free radical oxygene species : Using fluorescent probe and cofocal laser scanning microscope, H_2O_2 production was detected in cisplatin-treated S_3 cells. The treatment with catalase inhibited H_2O_2 production and the cytotoxicity in cisplatin-induced S_3 cells. In addition, H_2O_2 was shown to induce apoptosis, necrosis, oncosis and apoptotic oncosis in S_3cells. Since DNA fragmentation was detected in H_2O_2-treated S_3 cells, DNA fragmentation appeared not to be unique to apoptosis. (4) The involvement of oncogene : The increase in c-fos mHNA expression was observed in cisplatin-treated S_3 cells. Overexpression of bcl-2 inhibited the activation of caspase-3 and cell death in cisplatin-treated S_3 cellsThese results suggest that caspase, cell cycle progression, free radical oxygen species and oncogene are involved in cisplatin-induced apoptosis in S_3 cells. Less