【摘要】 目的研究N-乙酰半胱氨酸(NAC)对氯化镉(CdCl2)所致猪肾小管细胞系(LLC-PK1)DNA损伤的保护作用,为防制镉危害提供实验依据。方法以LLC-PK1细胞为实验对象,将细胞分为对照组,CdCl2处理组(1.5～6μg/ml),CdCl2与NAC联合处理组(CdCl2处理前1 h加入1 mmol/L NAC)。通过单细胞凝胶电泳(SCGE)试验检测细胞DNA损伤,用免疫组化方法检测细胞内8-羟基脱氧鸟苷(8-OhdG)的表达水平,用2’,7’-二氢二氯荧光素(DCFH)和苯二醛(OPT)测定细胞内活性氧类(ROS)以及还原性谷胱甘肽(GSH)水平。同时,以NAC为干预物,观察其对上述效应终点的影响。结果 CdCl2可致细胞DNA链断裂,诱发细胞内ROS产生增多,GSH水平下降,细胞核内8-OhdG表达增加,与对照组相比,差异有统计学意义(P<0.05或P<0.01)。NAC预处理后使DNA链断裂有所减轻,降低了ROS和8-OhdG表达水平,同时升高了GSH水平(P<0.05或P<0.01)。结论 NAC可有效的预防CdCl2引起的LLC-PK1细胞DNA损伤。更多还原

【Abstract】 Objective To study the protective effect of NAC on DNA damage in LLC-PK1 cells induced by cadmium,and provide scientific evidence against hazard of cadmium.Methods LLC-PK1 cells were divided into control group,CdCl2 groups(1.5-6 μg/mL) and NAC pretreated groups.DNA damage was determined by single cell gel electrophresis assay(SCGE),8-OHdG level was tested by immunocytochemical analysis,and ROS and GSH were measured by fluorescence method.As an intervenor,NAC was added into cultures together with CdCl2 to explore its preventive effects on oxidative damage and DNA damage induced by CdCl2.Results NAC significantly reduced the DNA strand breaks caused by cadmium(P<0.01).Moreover,NAC effectively suppressed cadmium-induced intracellular ROS formation and 8-OHdG level(P<0.05 or P<0.01).The GSH depletion induced by PAT in HepG2 cells was also attenuated by NAC pretreatment(P<0.05 or P<0.01).Conclusion NAC has a strong protective ability against the DNA damage caused by cadmium.更多还原