多壁碳纳米管致RAW264.7巨噬细胞毒性与氧化损伤研究

目的探讨多壁碳纳米管(MWCNTs)对小鼠巨噬细胞株RAW264.7细胞的体外细胞毒性和氧化损伤作用。方法用DNA钠盐提高MWCNTs的分散度,设4个浓度组(2.5、10、25和100μg/ml)、DNA钠盐溶剂对照组和生理盐水对照组,染毒24h后,用四甲基偶氮唑盐(MTT)方法观察细胞毒性,并根据染毒后细胞的总蛋白(TP)、乳酸脱氢酶(LDH)、一氧化氮(NO)、谷胱甘肽(GSH)、超氧化物歧化酶(SOD)和丙二醛(MDA)的变化情况分析MWCNTs的细胞毒性和氧化损伤作用。结果25μg/ml和100μg/ml浓度组细胞存活率及细胞毒性和氧化损伤指标均有不同程度的改变,呈一定的浓度-反应关系;随着染毒浓度的升高,细胞和其上清液中TP、LDH、NO和MDA含量随之升高,而GSH和SOD含量随之降低,且呈一定的暴露-反应关系;且与细胞发生融解破碎,间隙加大等形态学改变情况相符。结论MWCNTs对体外培养巨噬细胞株RAW264.7细胞具有细胞毒性和氧化损伤作用,且随剂量的增大而增强。

In vitro cytotoxicity and oxidative damage effects of multi-wall carbon nanotube on RAW264.7 macrophages

OBJECTIVE: To study the in vitro cytotoxicity and oxidative damages of multi-wall carbon nanotube (MWCNTs) on RAW264.7 macrophages. METHODS: The RAW264.7 macrophages were treated with different concentrations of MWCNTs (2.5, 10, 25 and 100 microg/ml), deoxyribonucleic acid sodium salt and saline for 24h. deoxyribonucleic acid sodium salt were used for increasing the dispersity of MWCNTs. MTT assays were applied to testing the viability of RAW264.7 cell. The contents of Total protein (TP), nitrogen monoxidum (NO), glutathione (GSH) and malondialdehyde (MDA) ,the activities of superoxide dismutase (SOD) and lactate dehydrogenase (LDH), were determined in supernate and intracellular. The morphological change of RAW 264.7 were also observed after exposure to MWCNTs for 24h. RESULTS: Compared with the controls, significant differences in the viability, cytotoxicity and oxidative damages were observed in 25 and 100 microg/ml groups. With the administration concentrations increased, intracellular or extracelluar levels of TP, LDH, NO and MDA in treatment groups increased, while the levels of GSH and SOD decreased with a significant dose-effect relationship. Which accord to the morphological change of RAW 264.7 after exposure to MWCNTs for 24h. CONCLUSION: MWCNTs could cause cytotoxicity and oxidative damages to RAW264.7 macrophages, with a dose-effect relationship.