N-乙酰半胱氨酸对纳米二氧化硅所致细胞毒性的抑制作用  

Inhibitory effects of N-acetyl-cysteine on SiO_2 nanoparticles-induced cytotoxicity

作　　者：耿维佳 李阳[1,2] 于永波[1,2] 于洋[1,2] 段军超[1,2] 杨玉梅[1,2] 邹洋[1,2,3] 孙志伟[1,2] 

机构地区：[1]首都医科大学公共卫生学院卫生毒理与卫生化学学系,北京100069 [2]首都医科大学环境毒理学北京市重点实验室,北京100069 [3]首都医科大学附属北京友谊医院北京热带医学研究所,北京100050

出　　处：《吉林大学学报（医学版）》2015年第3期486-490,I0004,共6页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金资助课题(81172704)

摘　　要：目的:探讨N-乙酰半胱氨酸(NAC)对纳米二氧化硅(SiO2)颗粒导致细胞中活性氧(ROS)水平升高的抑制作用,阐明纳米SiO2颗粒致细胞毒性的机制。方法:选用粒径为68nm的纳米SiO2颗粒,以体外培养的人正常肝细胞(L-02)为模型,分为对照组和不同浓度(1、2、5、10mmol·L-1)NAC预处理组、不同浓度(10、20、50、100mg·L-1)纳米SiO2颗粒暴露组和NAC预处理的纳米SiO2颗粒暴露组。采用MTT法测定不同浓度NAC预处理后的细胞存活率以及不同浓度NAC预处理后暴露于纳米SiO2颗粒的细胞存活率;倒置显微镜观察NAC预处理后暴露于纳米SiO2颗粒的细胞形态;荧光酶标仪检测NAC预处理后暴露于不同浓度纳米SiO2颗粒的细胞中ROS水平。结果:NAC预处理组细胞存活率均高于对照组,在5mmol·L-1浓度时达到峰值,但与对照组比较差异无统计学意义(P>0.05);不同浓度NAC能使暴露于纳米SiO2颗粒的细胞存活率升高,以5mmol·L-1 NAC的作用最明显(P<0.05);与纳米SiO2颗粒暴露组比较,NAC预处理的纳米SiO2颗粒暴露组细胞数目增多,细胞边界较明显;随纳米SiO2颗粒浓度的升高,细胞中ROS水平随之升高,呈现剂量依赖效应,在50和100mg·L-1浓度时与对照组比较差异有统计学意义(P<0.05);与相同浓度纳米SiO2颗粒暴露组比较,NAC预处理的纳米SiO2颗粒暴露组细胞中ROS水平降低,差异有统计学意义(P<0.05)。结论:NAC在一定程度上能够抑制纳米SiO2颗粒所致的细胞存活率下降和细胞中ROS水平升高,细胞中ROS水平升高是纳米SiO2颗粒导致人正常肝细胞毒性的作用机制之一。Objective To detect the inhibitory effects of N-acetyl-cysteine（NAC）on the increasing of reactive oxygen species（ROS）level induced by SiO2 nanoparticles,and to clarify the mechanism of cytotoxicity induced by SiO2 nanoparticles.Methods The 68 nm SiO2nanoparticles were selected and the in vitro cultured human normal liver L-02 cells were used as cell model.The L-02 cells were divided into control group,different concentrations of NAC（1,2,5,10 mmol·L^-1）pretreatment groups,different concentrations of SiO2 nanoparticle（10,20,50,100 mg·L^-1）groups and SiO2 nanoparticle exposure with NAC pretreatment groups. MTT assay was applied to measure the viabilities of the L-02 cells in NAC pretreatment groups with and without SiO2 nanoparticle exposure.The morphology of L-02 cells pretreated with NAC followed by SiO2 nanoparticles exposure was observed by inverted microscope.The intracellular ROS levels were measured by fluorescence microplate reader to evaluate NAC effects towards different concentrations of SiO2 nanoparticles.Results The cell viabilities in NAC pretreatment groups were elevated,and peaked in 5mmol·L^-1 group.However,compared with control group,the NAC did not increase the cell viability significantly（P〈0.05）.Compared with SiO2 nanoparticle exposure group without NAC,the cell viabilities in NAC pretreatment groups were increased（P〈0.05）.The image of NAC pretreatment group showed higher cell number and more distinct cell boundary compared with SiO2 nanoparticle group without NAC. With the increase of SiO2 nanoparticles concentration,the intracellular ROS levels were increased in a dose-dependent manner.Compared with ocntrol group,the ROS levels in 50 and100mg·L^-1 SiO2 nanoparticle groups were increased significantly（P 0.05）.The ROS levels in SiO2 nanoparticles exposure with NAC pretreatment groups were decreased compared with SiO2 nanoparticles exposure groups at the same concentration（P〈0.05）.Conclusion NAC can inhibit the decrease of cell viability and the increase

关 键 词：纳米二氧化硅 细胞毒性 N-乙酰半胱氨酸 活性氧 肝细胞L-02 

分 类 号：R99[医药卫生—毒理学] R114[医药卫生—药学]