改性超细炭黑诱发氧化应激的毒性效应与机理  

Toxic effects and mechanisms of oxidative stress induced by modified ultrafine carbon black

作　　者：贾晨号 刘汝涛[1] JIA Chenhao;LIU Rutao(School of Environment Science and Engineering,Shandong University,Qingdao 266200,Shandong,China)

机构地区：[1]山东大学环境科学与工程学院

出　　处：《山东大学学报（工学版）》2019年第3期120-128,共9页Journal of Shandong University（Engineering Science）

基　　金：国家自然科学基金资助项目(21477067);国家自然科学基金资助项目(21777088);高等学校博士学科点专项科研基金资助项目(708058)

摘　　要：为研究改性超细炭黑(modified ultrafine carbon black, MCB)诱发氧化应激的毒性效应与机理,将小鼠肝细胞和过氧化氢酶(catalase, CAT)暴露于不同质量浓度的MCB溶液中。采用CCK-8、丙二醛(malondialdehyde, MDA)含量和CAT活力检测等方法评价MCB的细胞毒性;利用荧光光谱,紫外-可见吸收光谱,圆二色谱等方法探究MCB对CAT构象的影响。结果表明:细胞活力随MCB质量浓度的升高而降低,低质量浓度的MCB(<30 mg/L)刺激细胞提高CAT的活力来保护自身免受氧化损伤,高质量浓度的MCB(>30 mg/L)使MDA在细胞内累积并造成氧化还原失衡,造成肝脏的氧化损伤;光谱学研究发现,MCB会改变CAT的二、三级结构和氨基酸微环境,使肽链紧缩极性增强,骨架结构的变化降低了CAT的活性。阐明MCB造成氧化应激效应的毒性机理,同时为纳米材料的毒理研究提供了参考。To study the toxic effects and mechanisms of oxidative stress induced by modified ultrafine carbon black(MCB), mouse hepatocytes and catalase(CAT) were exposed to MCB solutions. The cytotoxicity of MCB was assessed by CCK-8 kit, malondialdehyde(MDA) kit and CAT activity assay. The effects on CAT structure and function of MCB were investigated by utilizing fluorescence, UV-vis absorption and circular dichroism spectroscopy. The experiment results demonstrated that the hepatocyte viability decreased with the increase of MCB concentration. Low MCB doses(< 30 mg/L) increased CAT activity to protectcells from oxidative damage while high doses of MCB(> 30 mg/L) caused accumulation of MDA and redox imbalance in the cells, which induced oxidative damage in the liver. Spectroscopy studies found that MCB destroyed the secondary and tertiary structure of CAT and changed the microenvironment of amino acids, which made denaturation of the peptide chain. As a result, changes of skeleton structure reduced the activity of CAT. This study clarified the oxidative mechanism of MCB causing oxidative stress effects and provided a reference for the toxicity mechanism of nanomaterials.

关 键 词：改性超细炭黑 氧化应激 肝细胞 过氧化氢酶 荧光光谱 紫外-可见吸收光谱 

分 类 号：X503.1[环境科学与工程—环境工程]