纳米二氧化硅颗粒对肝HL-7702细胞的毒性作用

目的:探讨纳米二氧化硅(SiO₂)颗粒对肝细胞HL-7702的毒性作用,阐明其作用机制。方法:体外培养的人正常HL-7702肝细胞随机分为阴性对照组和12.5、25.0、50.0、100.0 mg·L^-1 SiO₂组。采用透射电子显微镜(TEM)和动态光散射(DLS)法对纳米SiO₂颗粒进行表征和粒径检测。细胞处理 24 h 后,HE染色观察各组细胞形态学;MTT实验检测各组细胞存活率;乳酸脱氢酶(LDH)活力实验检测各组细胞培养液中LDH活力;流式细胞术(FCM)检测各组细胞中活性氧(ROS)水平。结果:TEM观察,纳米SiO₂呈球形,颗粒大小较均匀一致,分散性较好,颗粒平均粒径为(65.87±9.02)nm;DLS法检测,纳米SiO₂颗粒在高纯水和RPMI-1640培养液中的水合粒径明显增大,分别为(124.57±8.02)和(139.32±9.93)nm。HE染色,纳米SiO₂颗粒能够导致HL-7702细胞形态改变,25.0和50.0 mg·L^-1 SiO₂组细胞数目减少,排列紊乱;100.0 mg·L^-1 SiO₂组细胞质皱缩、细胞排列稀疏,部分细胞呈凋亡的形态学表现。与阴性对照组比较,各浓度纳米SiO₂组HL-7702细胞存活率均下降,50.0和100.00 mg·L^-1 SiO₂组细胞存活率明显下降(P<0.05);50.0和100.00 mg·L^-1 SiO₂组培养液中LDH 活力明显升高(P<0.05),细胞中ROS水平明显升高(P<0.05)。结论:纳米SiO₂颗粒能够对HL-7702细胞产生毒性作用,并呈一定的浓度依赖效应;其毒性作用机制可能与细胞中ROS的产生有关联。

Cytotoxicity of SiO2 nanoparticles on liver HL-7702 cells

Objective To study the cytotoxicity of SiO₂ nanoparticles (NPs) on the liver HL-7702 cells,and to clarify its mechanism. Methods The in vitro cultured human normal liver HL-7702 cells were randomly divided into control group and 12.5,25.0,50.0,100.0 mg·L^-1 SiO₂ groups,respectively.Transmission electron microscope (TEM) was used to characterize the SiO₂ NPs,and dynamic light scattering(DLS) method was used to analyze the particle size of SiO₂ NPs.After 24 h exposure,the morphology of HL-7702 cells were observed by HE staining;MTT assay was used to determine the viability of HL-7702 cells;lactate dehydrogenase (LDH) release assay was used to detect the LDH activity in culture medium of HL-7702 cells;flow cytometry (FCM) was applied to examine the level of intracellular reactive oxygen species (ROS). Results The TEM results showed that the SiO₂ NPs were spherical,universally sized and more or less dispersed well,and the average particle size of SiO₂ NPs were (65.87±9.02) nm.The DLS method results manifested that the SiO₂ particle sizes of the SiO₂ NPs were (124.57±8.02) nm in high purity water and (139.32±9.93) nm in RPMI-1640 solution.The HE staining results revealed that the SiO₂ NPs could cause the morphological changes of HL-7702 cells,and the number of HL-7702 cells was reduced and the arrangement was disorder in 25.0 and 50.0 mg·L^-1 SiO₂ groups;in 100.0 mg·L^-1 SiO₂ group,the cells were shrunken and sparse,and part of the cells appeared the morphological features of apoptosis.Compared with control group,the cell viabilities in different concentrations of SiO₂ groups were decreased,especialy in 50.0 and 100.0 mg·L^-1 SiO₂ groups (P<0.05),while the LDH activities in culture medium and the intracellular ROS levels in 50.0 and 100.0 mg·L^-1 SiO₂ groups were increased (P<0.05). Conclusion SiO₂ NPs could cause the cytotoxicity on the HL-7702 cells in a concentration-dependent manner,and the cytotoxicity may be associated with the generation of intracellular ROS.