摘要:本研究旨在研究长期日粮添加纳米ZnO(3-35周)对小鼠发育、锌代谢、微量元素(Zn,Fe,Cu,Mn)分布的影响。测定纳米微粒的基本特征后,将纳米ZnO添加至基础日粮中,添加水平分别为0、50、500和5000mg / kg。研究结果表明,长期日粮添加50和500 mg / kg纳米ZnO对小鼠无明显毒性作用,但日粮添加5000mg / kg纳米ZnO显著降低了体重(从第4至16周),增加了胰、脑、肺相对重量。日粮添加5000 mg / kg纳米ZnO显著提高了血清谷丙转氨酶活性和锌水平,并显著提高了空肠锌代谢相关基因的mRNA表达水平,包括MT1,MT2,ZIP8,ZIP14,ZnT1,ZnT2和ZnT4。生物分布分析结果表明,日粮添加5000mg / kg纳米ZnO显著增加肝,胰,肾和骨骼(胫骨和腓骨)中锌的含量,对组织中Cu、Fe和 Mn的含量无显著影响,但肝脏Fe含量和胰腺Mn水平除外。本研究结果提示,长期日粮添加50和500 mg / kg纳米ZnO对小鼠无明显毒性作用,但高剂量纳米ZnO(5000mg / kg)对小鼠发育有一定毒性作用,并改变了锌的生物学分布与代谢。28138 毕业论文关键词:纳米氧化锌;小鼠;锌代谢;微量元素
Effects of Long-Term Exposure to Zinc Oxide Nanoparticles on Development, Zinc Metabolism and Biodistribution of Minerals (Zn, Fe, Cu, Mn) in Mice
Abstract: This study aimed at investigating long term effects of zinc oxide nanoparticles (nano-ZnOs) on development, zinc metabolism and biodistri-bution of minerals (Zn, Fe, Cu, and Mn) in mice from week 3 to 35. After the characteristics of nano-ZnOs were determined, they were added into the basal diet at 0, 50, 500 and 5000 mg/kg. Results indicated that added 50 and 500 mg/kg nano-ZnOs showed minimal toxicity. However, 5000 mg/kg nano-ZnOs significantly decreased body weight (from week 4 to 16) and increased the relative weights of the pancreas, brain and lung. Added 5000 mg/kg nano-ZnOs significantly increased the serum glutamic-pyruvic transaminase activity and zinc con-tent, and significantly enhanced mRNA expression of zinc metabolism-related genes, including MT 1(32.66 folds), MT 2 (31.42 folds), ZIP8 (2.21folds), ZIP14 (2.45 folds), ZnT1 (4.76 folds), ZnT2 (6.19 folds) and ZnT4 (1.82 folds). The biodistribution determination showed that there was a significant accumulation of zinc in the liver, pancreas, kidney, and bones (tibia and fibula) after receiving 5000 mg/kg nano-ZnO diet, while no signif-icant effects on Cu, Fe, and Mn levels, except for liver Fe content and pancreas Mn level. Our results demonstrated that long term exposure to 50 and 500 mg/kg nano-ZnO diets showed minimal toxicity. However, high dose of nano-ZnOs (5000 mg/kg) caused toxicity on development, and altered the zinc metabolism and biodistribution in mice.
Key words: Zinc oxide nanoparticles;mice;Zinc metabolism;Trace elements
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