XRCC1参与修复鼠尾草酚诱导的DNA损伤

XRCC1 is involved in the repair of carnosol-induced DNA damage

目的研究鼠尾草酚(carnosol,CAR)诱导的DNA损伤修复机制。方法采用CCK-8试验检测CAR对TK6细胞(人类淋巴母细胞)增殖的影响;利用染色体畸变试验和免疫荧光分析试验分析CAR对TK6细胞的损伤作用和修复机制;采用流式细胞术检测细胞凋亡情况。结果CAR对TK6细胞呈剂量依赖性抑制,且与野生型(wide type,WT)细胞相比,敲除XRCC1基因的细胞(XRCC1^(-/-))对CAR呈现出敏感性;20μmol·L^(-1)CAR连续处理TK6细胞24 h后,XRCC1^(-/-)细胞比WT细胞的染色体断裂更多;40μmol·L^(-1)CAR连续处理TK6细胞6 h后,XRCC1^(-/-)细胞比WT细胞产生更多的γ-H2AX foci;40μmol·L^(-1)CAR连续处理TK6细胞24 h后,XRCC1^(-/-)细胞比WT细胞凋亡程度增加。结论CAR可以诱导XRCC1^(-/-)细胞比WT TK6细胞产生更多的DNA损伤。因此,XRCC1参与了细胞中CAR造成的DNA损伤的修复反应。

Objective To study the repair mechanism of DNA damage induced by carnosol(CAR).Methods CCK-8 assay was used to detect the effect of CAR on the proliferation of TK6 cells(human lymphoblast cells).The chromosomal aberration test and immunofluorescence assay were used to analyze the damage and repair mechanism of CAR on TK6 cells.Flow cytometry was used to detect the apoptosis.Results CAR inhibited the survival of TK6 cells in a dose-dependent manner,and compared with wild type(WT)cells,XRCC1 deficient cells(XRCC1^(-/-))showed a high sensitivity to CAR.After treatment of 20μmol·L^(-1)CAR for 24 h,XRCC1^(-/-)cells caused more chromosome breaks than WT cells.Compared with WT cells,CAR induced moreγ-H2 AX foci in XRCC1^(-/-)cells after exposure to 40μmol·L^(-1)CAR for 6 h.After treatment of 40μmol·L^(-1)CAR for 24 h,XRCC1^(-/-)cells had more apoptosis than WT cells.Conclusion Compared with WT cells,CAR can induce more DNA damage in XRCC1^(-/-)cells.Therefore,XRCC1 is involved in the repair process of DNA damage caused by CAR.