Martins Airton da Cunha, Azevedo Lara Ferreira, de Souza Rocha Cecília Cristina, Carneiro Maria Fernanda Hornos, Venancio Vinicius Paula, de Almeida Mara Ribeiro, Antunes Lusânia Maria Greggi, de Carvalho Hott Rodrigo, Rodrigues Jairo Lisboa, Ogunjimi Abayomi T, Adeyemi Joseph A, Barbosa Fernando
a Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas , Universidade de São Paulo , Av. do Café s/n, Bairro Monte Alegre, Ribeirão Preto , São Paulo , Brazil.
b Instituto de Ciência, Engenharia e Tecnologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri , Teófilo Otoni , Minas Gerais , Brazil.
J Toxicol Environ Health A. 2017;80(19-21):1156-1165. doi: 10.1080/15287394.2017.1357376. Epub 2017 Sep 11.
The increasing production of silver nanoparticles (AgNPs) and titanium dioxide nanoparticles (TiONPs) has resulted in their elevated concentrations in the environment. This study was, therefore, aimed at determining the distribution, redox parameters, and genotoxic effects in male Wistar rats that were treated with either AgNP or TiONP individually, as well as under a co-exposure scenario. Animals were exposed via oral gavage to either sodium citrate buffer (vehicle), 0.5 mg/kg/day TiONP, 0.5 mg/kg/day AgNP or a mixture of TiONPs and AgNPs. Exposure lasted 45 days after which rats were sacrificed, and tissue biodistribution of Ag and Ti measured. The blood concentration of glutathione (GSH) and activities of glutathione peroxidase (GPx) and catalase (CAT) were determined while the genotoxicity was analyzed using the comet assay in peripheral blood and liver cells. The tissue concentrations of Ag followed the order; blood > liver > kidneys while for Ti the order was kidneys > liver > blood. There was no significant change in the measured redox parameters in animals that were exposed to TiONPs. However, there was a significant increase in GSH levels accompanied by a reduction in the GPx activity in AgNP-treated and co-exposed groups. The individual or co-exposure to TiONP and AgNP did not markedly induce genotoxicity in blood or liver cells. Data showed that TiONP did not produce significant oxidative stress or genotoxicity in rats at the dose used in this study while the same dose level of AgNPs resulted in oxidative stress, but no noticeable adverse genotoxic effects.
银纳米颗粒（AgNPs）和二氧化钛纳米颗粒（TiONPs）产量的不断增加导致其在环境中的浓度升高。因此，本研究旨在确定单独用AgNP或TiONP处理的雄性Wistar大鼠以及在共同暴露情况下的分布、氧化还原参数和遗传毒性效应。动物通过口服灌胃给予柠檬酸钠缓冲液（载体）、0.5mg/kg/天的TiONP、0.5mg/kg/天的AgNP或TiONPs和AgNPs的混合物。暴露持续45天，之后处死大鼠，并测量Ag和Ti的组织生物分布。测定了谷胱甘肽（GSH）的血药浓度以及谷胱甘肽过氧化物酶（GPx）和过氧化氢酶（CAT）的活性，同时使用彗星试验分析外周血和肝细胞中的遗传毒性。Ag的组织浓度顺序为：血液＞肝脏＞肾脏，而Ti的顺序为：肾脏＞肝脏＞血液。暴露于TiONPs的动物中，所测氧化还原参数没有显著变化。然而，在AgNP处理组和共同暴露组中，GSH水平显著升高，同时GPx活性降低。单独或共同暴露于TiONP和AgNP均未在血液或肝细胞中明显诱导遗传毒性。数据表明，在本研究使用的剂量下，TiONP在大鼠中未产生显著的氧化应激或遗传毒性，而相同剂量水平的AgNPs则导致了氧化应激，但没有明显的不良遗传毒性效应。
