摘要
目的 :探讨过氧化氢 (H2 O2 )诱导HepG2细胞的DNA损伤和凋亡效应在细胞周期不同时相的敏感性 .方法 :利用胸腺嘧啶核苷 (TdR)阻断肝癌HepG2细胞于G1期末后 ,去除胸苷 ,培养不同时间 ,分别得到同步化的G1期、S期和G2 /M期细胞 ,1 5 0 μmol/L的H2 O2 处理 1 2h ,采用单细胞凝胶电泳技术 (SCGE)测定细胞的DNA损伤 ;将各期细胞用2 0 0 μmol/L的H2 O2 处理 ,采用流式细胞术测定细胞凋亡 .同时实验设立未同步化和正常对照组 .结果 :①分别获得88.6 %的G1期细胞、78.1 %的S期细胞、6 6 .8%的G2 /M期细胞 .②SCGE结果显示 ,同步化于S期和G2 /M期细胞的DNA尾长明显增长 ,尾部DNA百分比含量和尾矩明显增加 ,其中S期细胞效应最为显著 .③凋亡检测结果显示 ,同步化各组细胞的凋亡率明显高于未同步化组 ,以S期最为显著 .结论 :H2 O2 诱导HepG2细胞DNA损伤和细胞凋亡在细胞周期的不同时相效应敏感性不同 。
AIM: To study the DNA injury and apoptosis induced by hydrogen peroxide(H 2O 2)in various phases in cell cycle of HepG2 cells. METHODS: HepG2 cells were blocked by TdR in G1 phase of cell cycle, and then cultured for different hours after TdR was removed. Synchronous G1 phase cells, S phase cells and G2/M phase cells were collected, respectively and treated for 12 hours by 150 μmol/L H 2O 2. The DNA injury was detected by single cell gel electrophoresis (SCGE). Synchronous cells in various phases were treated for 12 hours by 200 μmol/L H 2O 2 and apoptosis was detected by flow cytometry. Non synchronous and normal control was set in the experiment. RESULTS: ① 88.6% G1 phase cells, 78.1% S phase cells and 66.8% G2/M phase cells were collected. ② The results of SCGE showed that the tail DNA length, the percentage of tail DNA and tail moment increased obviously in synchronous S phase cells and G2/M phase cells, especially in S phase of HepG2 cells. ③ The results of flow cytometry demonstrated that apoptosis rate increased obviously in synchronous HepG2 cells, especially in S phase of HepG2 cells. CONCLUSION: It is suggested that the DNA injury and apoptosis of HepG2 cells induced by H2O2 might have different sensibilities in different phases of cell cycle, and they occur mainly in S phase of cell cycle.
出处
《第四军医大学学报》
北大核心
2004年第8期744-748,共5页
Journal of the Fourth Military Medical University
基金
军队"十五"指令课题 (0 1L0 77)
