硒化镉/硫化锌量子点对HepG2细胞增殖和凋亡相关蛋白的影响  

Effect of CdSe/ZnS quantum dots on HepG2 cell viability and apoptosis-related proteins

作　　者：陈婷[1,2] 郑至嘉 许改霞[1] 田靖琳 林苏霞[3] 黄嘉诚[2] 李洁凤 黄其俊[2] 王晓梅[2] 林桂淼[2] CHEN Ting ZHENG Zhijia XU Gaixia TIAN Jinglin LIN Suxia HUANG Jiacheng LI Jiefeng HUANG Qijun WANG Xiaomei LIN Guimiao(Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education/Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 Department of Physiology, School of Basic Medical Sciences, Shenzhen University Health Sciences Center, Shenzhen 518060 Medical Center of Obstetrics and Gynecology Reproductive, the University of Hong Kong-Shenzhen Hospital, Shenzhen 518053, Guangdong, China)

机构地区：[1]深圳大学光电工程学院,广东省/教育部光电子器件与系统重点实验室,广东深圳518060 [2]深圳大学医学部基础医学院生理学教研室,广东深圳518060 [3]香港大学深圳医院妇产科生殖医学中心,广东深圳518053

出　　处：《癌变．畸变．突变》2017年第1期18-22,共5页Carcinogenesis,Teratogenesis & Mutagenesis

基　　金：国家自然科学基金(21677102,31671491);深圳市基础研究项目(JCYJ20140418182819164,JCYJ20140418095735543);深圳大学面上项目(827-000100,海外高层次人才启动项目)

摘　　要：目的:以人肝癌HepG2细胞为对象,研究硒化镉,硫化锌(cdSe/ZnS)量子点对肝癌细胞的毒性及其机制。方法:用透射电子显微镜观察CdSe/ZnS量子点的微观结构,用荧光分光光度计测量CdSe/ZnS量子点的吸收和发射光谱。将HepG2细胞分为3组,2个实验组分别与0.5、5 nmol/L CdSe/ZnS量子点共孵育,对照组不作处理。采用激光共聚焦显微镜观察共孵育4 h后细胞对量子点的摄取情况和量子点在细胞中的定位,用流式细胞术检测细胞对量子点的摄取率;用四甲基噻唑蓝(MTT)法检测共孵育24和48 h后CdSe/ZnS量子点对HepG2细胞增殖的影响;用Western blot法检测共孵育4 h后CdSe/ZnS量子点对HepG2细胞凋亡相关蛋白Caspase-9和Caspase-3的影响。结果:CdSe/ZnS量子点粒径小且分散性好,吸收光谱宽发射光谱窄而对称。0.5和5 nmol/L的CdSe/ZnS量子点处理4 h后均可被HepG2细胞摄取并定位于胞浆内,且摄取率达到99%以上。0.5、5 nmol/L CdSe/ZnS量子点处理24 h后,细胞相对存活率分别为99.2%±5.1%、99.5%±7.0%,与对照组比较差异无统计学意义(P>0.05);0.5、5 nmol/LCdSe/ZnS量子点处理48 h后,细胞相对存活率分别为91.6%±3.2%和75.1%±4.6%,显著低于对照组(P<0.05或P<0.01)。Western blot结果显示,与对照组相比,实验组HepG2细胞凋亡相关蛋白Caspase-9和Caspase-3表达量均增加。结论:CdSe/ZnS量子点可被HepG2细胞摄取并抑制HepG2细胞的增殖,此抑制作用可能与其诱导细胞凋亡相关蛋白表达有关。OBJECTIVE： To investigate the mechanism of cytotoxicity of CdSe/ZnS quantum dots （CdSe/ZnS QDs） on HepG2 cells. METHODS： Morphological images of CdSe/ZnS QDs were obtained with a transmission electron microscope （TEM） and the fluorescence spectra of the QDs were determined by a spectrophotometer. After treatment with 0,0.5 and 5 nmol/L CdSe/ZnS QDs for 4 hours, the HepG2 cells were imaged under a laser scanning confocal microscope （LSCM） and the uptake efficiency of the QDs was evaluated quantitatively using a flow cytometry machine. After treatment for 24 and 48 hours, the effect on cell proliferation was measured using the MTT assay. The Western blot assay was used to evaluate the effect on apoptosis-related proteins, Casepase-9 and Casepase-3. RESULTS： CdSe/ZnS QDs had a particle size of around 10 nm and the nanocrystals were highly mono-dispersed. The QDs exhibited a broad absorption spectrum from 250 nm to 500 nm and a narrow emission spectrum from 600 nm to 700 nm. The QDs entered cells and remained mostly in the cytoplasm within 4 hours. The uptake efficiency of the QDs was up to 99%. Compared with controls, cells treated with 0.5 and 5 nmol/L QDs for 24 hours exhibited no obvious suppression on cell proliferation but showed highly suppressed cell proliferation 48 hours later （P 〈 0.05）. Compared with controls, the expression levels of Caspase-9 and Caspase-3 were increased in QDs-treated cells. CONCLUSION： The results suggest that CdSe/ZnS QDs which were taken in by HepG2 cells inhibited cell proliferation. The inhibition could be related to the induction of Caspase-9 and Caspase-3 expression.

关 键 词：硒化镉/硫化锌 量子点 细胞增殖 细胞凋亡 细胞毒性 

分 类 号：Q616[生物学—生物物理学]