Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546, USA.
Environ Pollut. 2012 Dec;171:249-55. doi: 10.1016/j.envpol.2012.08.003. Epub 2012 Sep 5.
Short-term changes in levels of expression of nine stress response genes and oxidative damage of proteins were examined in Eisenia fetida exposed to polyvinylpyrrolidone (PVP) coated Ag nanoparticles (Ag-NP) and AgNO(3) in natural soils. The responses varied significantly among days with the highest number of significant changes occurring on day three. Similarity in gene expression patterns between Ag-NPs and AgNO(3) and significant relationships of expression of CAT and HSP70 with Ag soil concentration suggest similarity in toxicity mechanisms of Ag ions and NPs. Significant increases in the levels of protein carbonyls on day three of the exposure to both ions and Ag-NPs indicate that both treatments induced oxidative stress. Our results suggest that Ag ions drive short term toxicity of Ag-NPs in E. fetida. However, given that <15% of Ag in the NPs was oxidized in these soils, dissolution of Ag-NPs is likely to occur after or during their uptake.
研究了在天然土壤中，暴露于聚乙烯吡咯烷酮（PVP）包覆的银纳米颗粒（Ag-NP）和 AgNO3的赤子爱胜蚓体内，9 种应激反应基因表达水平的短期变化和蛋白质氧化损伤。这些反应在不同天数之间差异显著，其中第 3 天发生的显著变化数量最多。Ag-NP 和 AgNO3之间的基因表达模式相似，以及 CAT 和 HSP70 的表达与 Ag 土壤浓度之间存在显著关系，表明 Ag 离子和 NPs 的毒性机制相似。在暴露于两种离子和 Ag-NP 的第 3 天，蛋白质羰基水平显著增加，表明这两种处理均诱导了氧化应激。我们的研究结果表明，Ag 离子是导致 Ag-NP 在赤子爱胜蚓体内短期毒性的原因。然而，鉴于这些土壤中只有<15%的 NPs 中的 Ag 被氧化，Ag-NP 的溶解可能发生在其吸收之后或期间。
