Villacis Rolando A R, Filho José S, Piña Benjamin, Azevedo Ricardo B, Pic-Taylor Aline, Mazzeu Juliana F, Grisolia Cesar K
Department of Genetics and Morphology, Institute of Biological Sciences, University of Brasília-UnB, Brasília, DF, Brazil.
Department of Environmental Chemistry, IDAEA-CSIC, Barcelona, Catalonia, Spain.
Aquat Toxicol. 2017 Oct;191:219-225. doi: 10.1016/j.aquatox.2017.08.004. Epub 2017 Aug 8.
The increasing use of nanotechnology in the last decade has raised concerns about the impact of nanoparticles in the environment. In particular, the potential harmful effects of iron oxide nanoparticles (IONPs) in aquatic organisms have been poorly addressed. We analyze here the toxic effects induced by IONPs in zebrafish using a combination of classical (genotoxicity, oxidative stress) and molecular (transcriptomic) methodologies. Adult animals were exposed for 96h to five sub-lethal IONP concentrations, ranging from 4.7 to 74.4mg/L. Comet and micronucleus assays revealed a significant number of DNA lesions induced by IONPs at all concentrations tested. Conversely, the thiobarbituric acid reactive substances (TBARS) test detected only a mild oxidative damage in liver cells (∼1.5-fold increase of malondialdehyde concentrations) and only at the two higher IONP concentrations tested. Microarray analysis of liver samples identified 953 transcripts (927 unique genes) differentially expressed between controls and IONP-exposed samples. Subsequent functional analysis identified genes related to cation/metal ion binding, membrane formation, and morphogenesis among the transcripts overrepresented upon IONP treatments, whereas mRNAs encompassing genes associated with RNA biogenesis, translation, ribosomes, and several metabolic processes became underrepresented in treated samples. Taken together, these results indicate considerable genotoxic effects of IONPs combined with general negative effect on cell growth and on the ability of the cell produce new proteins. On the contrary, IONPs showed only a limited capacity to induce oxidative stress. To our knowledge, this is the first study on IONPs toxicity using such an integrative approach in an aquatic organism.
在过去十年中，纳米技术的使用日益增加，这引发了人们对纳米颗粒在环境中影响的担忧。特别是，氧化铁纳米颗粒（IONPs）对水生生物的潜在有害影响尚未得到充分研究。我们在此使用经典（遗传毒性、氧化应激）和分子（转录组学）方法相结合的方式，分析了IONPs对斑马鱼的毒性作用。成年动物暴露于五种亚致死浓度的IONPs中96小时，浓度范围为4.7至74.4mg/L。彗星试验和微核试验表明，在所有测试浓度下，IONPs均诱导了大量的DNA损伤。相反，硫代巴比妥酸反应性物质（TBARS）试验仅在测试的两个较高IONP浓度下，检测到肝细胞中轻微的氧化损伤（丙二醛浓度增加约1.5倍）。对肝脏样本的微阵列分析确定了953个转录本（927个独特基因）在对照和IONP暴露样本之间差异表达。随后的功能分析确定，在IONP处理后，与阳离子/金属离子结合、膜形成和形态发生相关的基因在转录本中过度表达，而包含与RNA生物合成、翻译、核糖体和几个代谢过程相关基因的mRNA在处理后的样本中表达不足。综上所述，这些结果表明IONPs具有相当大的遗传毒性作用，并对细胞生长和细胞产生新蛋白质的能力产生普遍的负面影响。相反，IONPs诱导氧化应激的能力有限。据我们所知，这是首次在水生生物中使用这种综合方法研究IONPs毒性的研究。
