纳米ZnO对小鼠抗氧化防御系统的影响

目的探讨纳米ZnO对小鼠抗氧化防御系统的影响。方法将30只健康清洁级CD-ICR小鼠随机分为对照(1%羧甲基纤维素钠)组、小粒径(10～20nm)纳米ZnO染毒组和大粒径(60～80nm)纳米染毒组,每组10只,雌雄各半。以5g/kg剂量一次性经口灌胃染毒。染毒14天后称重,处死小鼠,取出小鼠的肝脏、肾脏、脾脏和心脏称重,并计算脏器系数。分别测定各脏器中丙二醛(MDA)和还原型谷胱甘肽(GSH)含量,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活力以及锌(Zn)元素含量。结果各组小鼠体重及肝脏、肾脏、脾脏、心脏的脏器系数间比较,差异无统计学意义(P0.05)。与对照组相比,大粒径纳米ZnO染毒组小鼠肾脏和小粒径纳米ZnO染毒组小鼠脾脏中SOD活力均下降,大、小粒径纳米ZnO染毒组小鼠肾脏和小粒径纳米ZnO染毒组小鼠心脏中MDA含量均上升,小粒径纳米ZnO染毒组小鼠脾脏和心脏中CAT活力均下降,大、小粒径纳米ZnO染毒组小鼠肾脏和小粒径纳米ZnO染毒组小鼠脾脏中GSH含量均下降,大粒径纳米ZnO染毒组小鼠肾脏中Zn含量均升高,差异有统计学意义(P0.05或P0.01)。结论肾脏、脾脏和心脏均受到不同程度的氧化损伤,肾脏可能是纳米ZnO灌胃染毒后的主要蓄积器官。

Impact of Nano-ZnO Particles on the Antioxidant System of Mice

Objective To study the impact of the nano-ZnO particles on the antioxidant system of mice. Methods Thirty ICR mice were randomly divided into three groups, the control group, small size group(10-20 nm) and large size group(60-80 nm).The mice were treated by a single gavage of zinc oxide nanoparticles at the dose of 5 g/kg weight with two different sizes. Fourteen days after treatment,the body weights were measured and the mice were sacrificed. The tissues of liver, kidney, spleen and heart were collected to evaluate the coefficient of organs, the levels of superoxide dismutase (SOD),malondialdehyde (MDA),catalase (CAT) and glutathione (GSH) as well as to analyze the Zn contents in the organs. Results There were no significant differences between the control and nano-size groups in the body weights and the coefficients of liver, kidney, spleen and heart in the mice. The SOD levels in the kidney of large size group and the spleen of small size group decreased compared with the group of control; The MDA contents in the kidney of two nano-groups and the heart of small size group increased; The CAT levels in the kidney and heart of the small group as well as the GSH contents in the kidney of two nano-groups and the spleen of small group decreased compared with the control; In addition ,the Zn contents in the kidney of large size group was higher than that in the control group; Significant differences were observed above between the exposure groups and control group (P＜0.05 or P＜0.01). Conclusion The kidney,spleen and heart of mice treated with the zinc oxide nanoparticles suffered oxidative damage in different extent and the kidney may be a cumulative organ after oral exposure to the zinc oxide nanoparticles.