纳米二氧化钛对大鼠氧化应激水平及海马组织结构的影响  

Effects of nano-TiO2exposure on oxidative stress and hippocampus structure in rats

作　　者：王文斌[1] 李仓廪[1] 安丽红[1] 张凤梅[1] 辛菲[2] 赵慧男[1] 冯德达 李杰[1] 李国珍[1] 

机构地区：[1]山东大学公共卫生学院环境与健康系,山东济南250012 [2]大连医科大学公共卫生学院

出　　处：《环境与健康杂志》2013年第12期1054-1057,F0003,共5页Journal of Environment and Health

基　　金：山东省自然科学基金青年基金(ZR2010HQ023);山东大学自主创新基金自然科学类专项(2010TS033);山东大学公共卫生学院青年人才创新基金(201001)

摘　　要：目的研究纳米二氧化钛对大鼠体内氧化应激水平及大鼠海马组织结构的影响。方法将32只健康SPF级雄性Wistar大鼠随机分为4组,分别为对照(蒸馏水)组和低(250 mg/kg)、中(500 mg/kg)、高(1 000 mg/kg)剂量纳米二氧化钛组,每组8只。采用灌胃方式进行染毒,每天1次,连续染毒14 d。分别在染毒第3、7、14天测定大鼠血浆中总超氧化物歧化酶(T-SOD)活力、谷胱甘肽过氧化物酶(GSH-Px)活力、总抗氧化能力(T-AOC)及丙二醛(MDA)含量;实验结束后,观察海马组织结构的变化。结果与对照组比较,第3、7、14天高剂量纳米二氧化钛组血浆中T-SOD、GSH-Px活力和T-AOC均明显降低,MDA含量均明显升高;中剂量纳米二氧化钛组T-SOD活力在第3、14天明显降低,GSH-Px活力在第14天明显降低,T-AOC在第3天明显降低,MDA含量在第7、14天明显升高,差异均有统计学意义(P<0.05);而低剂量纳米二氧化钛组以上4个指标均无显著改变。在各剂量纳米二氧化钛染毒组内,仅低、中剂量组第14天T-SOD活力显著低于第3天,差异均有统计学意义(P<0.05)。各染毒组海马区神经细胞出现不同程度的病理改变,如染色质溶解、核固缩、细胞密度降低等现象,中、高剂量组可见神经细胞坏死形成的空泡状区域。结论本实验条件下,纳米二氧化钛染毒可引起体内氧化应激反应增强,并可导致大鼠海马组织结构损伤。Objective To study the effects of nano-TiO2 exposure on oxidative stress level and hippocampus structure in rats. Methods A total of 32 SPF Wistar rats were randomly divided into four groups ： control group （eaqual volume of distilled water） , three nano-TiO2 groups （250,500 and 1 000 mg/kg）. Titanium dioxide was given to rats by oral gavage for 14 consecutive days. Then the levels of total superoxide dismutase （T-SOD）,glutathione peroxidase （GSH-Px）,total antioxidant capacity （T-AOC） and malondiaidehyde（MDA） in plasma were measured after three days,seven days and 14 days of exposure to nano-TiO2 respectively. The pathological examination of hippocampus was conducted. Results Compared with the control group,the activities of T-SOD,GSH-Px and T-AOC were significantly decreased and the contents of MDA were significantly increased after exposure to nano-TiO2 for 3 days,7 days and 14 days in 1 000 mg/kg group （P〈0.05）; The activities of T-SOD were significantly decreased after exposure to nano-TiO2 for 3 days and 14 days in 500 mg/kg group （P〈0.05）; The aetivities of GSH-Px were significantly decreased after exposure to nano-TiO2 for 14 days in 500 mg/kg group （P〈0.05）; The levels of T-AOC were significantly deereased after exposure to nano-TiO2 for 3 days in 500 mg/kg group （P〈0.05）; The contents of MDA were significantly increased after exposure to nano-TiO2 for 7 days and 14 days in 500 mg/kg group （P〈0.05）. There was no significant change in 250 mg/kg group in the above four indexes. In each dose of nano-TiO2 exposure group, the T-SOD activities at 14th day were significantly lower than that at 3th day in 250 mg/kg and 500 mg/kg groups. Pathological changes appeared in the hippocampus of nano-TiO2 exposed groups,such as nuclear condensation,ehromatolysis and lower cell density. Neurons necrosis and vacuoles were observed in 500 and 1 000 mg/kg groups. Conclusion Nano-Ti02 exposure may enhanee the oxidative stress level and cause damages in hippocampus tissue

关 键 词：纳米二氧化钛 海马 氧化应激 

分 类 号：R994.6[医药卫生—毒理学]