摘要
目的研究纳米氧化钛(nano-TiO2)对大鼠神经胶质细胞的毒性作用。方法①体外实验:制备3种粒径10,20和200nm的nano-TiO2颗粒悬液,分别以6.25,12.5,25,50和100mg·L-1对大鼠星形胶质细胞进行72h染毒培养,应用磺基罗丹明B法检测nano-TiO2对星形胶质细胞存活率的影响。②体内实验:Wistar大鼠气管内分别注入上述3种粒径的nano-TiO2悬液,每种粒径设0.1,1.0和10.0mg·kg-13个剂量组,每组3只,72h后分别用电感耦合等离子质谱和放射免疫法检测大鼠脑组织中nano-TiO2的含量和白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)和IL-10水平的变化,并通过光学显微镜和透射电镜观察nano-TiO2对大鼠神经胶质细胞形态的影响。结果①体外实验发现,nano-TiO2对大鼠星形胶质细胞存活率的抑制作用具有明显的浓度-效应关系,3种粒径10,20和200nm的nano-TiO2与胶质细胞培养72h,其半数抑制浓度分别为55.9,66.0和3827.0mg·L-1;细胞形态亦发生明显变化,细胞排列稀疏,间隙增大,胞内颗粒物增多,细胞透明度下降。②体内实验发现,粒径10和20nm的nano-TiO20.1mg·kg-1及粒径200nm的nano-TiO20.1,1.0和10.0mg·kg-1组,大鼠脑组织中的nano-TiO2,IL-1β,TNF-α及IL-10浓度与对照组比较无明显变化;粒径10和20nm的nano-TiO21.0及10.0mg·kg-1组大鼠脑组织中nano-TiO2,IL-1β,TNF-α及IL-10浓度随nano-TiO2剂量的增加而增加;病理学观察结果表明,nano-TiO2破坏大鼠血脑屏障,造成脑组织坏死,并进入神经胶质细胞内,引起炎症反应和细胞水肿。结论Nano-TiO2对大鼠神经胶质细胞具有细胞毒性作用,其作用强度与粒径大小有关,其作用机制可能与诱导炎症反应有关。
OBJECTIVE To study the cytotoxicity of titanium dioxide nanoparticles (nano-TiO2)in neuroglia cells. METHODS ① In vitro, rat astrocytes were exposed to nano-TiO2 of 3 different diameters (10, 20 and 200 nm) at 5 different concentrations (6.25, 12.5, 25, 50 and 100 mg·L-1). Sulforhodamine B staining assay was carried out to evaluate the survival rate of nano-TiO2-treated cells for 72 h. ② In vivo, nano-TiO2 of these 3 different diameters at 0.1, 1.0 and 10.0 mg·kg-1 were intratracheally instilled into the bronchus of Wistar rats, respectively, 3 rats in each group. Seventy-two hours later, the content of nano-TiO2 and levels of interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and IL-10 in brain tissue were measured with ICP-MS and radioimmunoassays. In addition, cellular morphology of rat neuralgia cells was observed by the light microscope and transmission electron microscope. RESULTS ① In vitro, the inhibiting effect of nano-TiO2 on the cell survival rate was significantly enhanced in a concentration-dependent manner and IC50of nano-TiO2 of the 3 diameters was 55.9, 66.0 and 3827.0 mg·L-1 at 72 h. There were also obvious changes in cellular configuration, such as sparse arrangement, increscent cell space, increased intracellular particles and decreasing cellular transparency. ② In vivo, when the rats were exposed to nano-TiO2 of 10 and 20 nm in diameter in 0.1 mg·kg-1or nano-TiO2 of 200 nm in diameter in 3 dosages, the contents of nano-TiO2, IL-1β,TNF-α and IL-10 in rat brain tissue did not show significant difference in the control and nano-TiO2-treated groups; when the rats were exposed to nano-TiO2 of 10 and 20 nm in diameter in 1.0 and 10.0 mg·kg-1, the contents of nano-TiO2 and the 3 cytokines in brain tissue increased compared with control group, especially nano-TiO2 in 10.0 mg·kg-1 group. Pathological observation indicated that the blood-brain-barrier was destroyed by nano-TiO2, which resulted in brain tissue necrosis and the entrance of nano-TiO2 into neuroglia cells to induce inflammation and cellular edema. CONCLUSION Nano-TiO2 is toxic to rat neuroglia cells. This toxicity may relate to the particle size and the mechanism may be associated with its induction of inflammation.
出处
《中国药理学与毒理学杂志》
CAS
CSCD
北大核心
2010年第2期116-121,共6页
Chinese Journal of Pharmacology and Toxicology
基金
国家科技部质检公益性行业科研专项资助项目(2007GY10-60)~~