Ecotoxicity of single‐wall carbon nanotubes to freshwater snail Lymnaea luteola L.: Impacts on oxidative stress and genotoxicity

Mammalian studies have raised concerns about the toxicity of carbon nanotubes, but there is very limited data on ecogenotoxicity to aquatic organisms. The aim of this study was to determine eco‐geno toxic effects of single walled carbon nanotubes (SWCNTs) in fresh water snail, Lymnea luteola (L. luteola). A static test system was used to expose L. luteola to a freshwater control, 0.05, 0.15, 0.30, 0.46 mg/L SWCNTs for up to 4 days. SWCNTs changed a significant reduction in glutathione, glutathione‐S‐transferase, and glutathione peroxidase with in hepatopancreas of L. luteola. Lipid peroxidation (LPO) and catalase showed dose‐ and time‐dependent and statistically significant increase in hepatopancreas during SWCNTs exposure compared with control. However, a significant (p < 0.01) induction in DNA damage was observed by the comet assay in hepatopancreas cells treated with SWCNTs. These results demonstrate that SWCNTs are ecogenotoxic to freshwater snail L. luteola. The oxidative stress and comet assay can successfully be used as sensitive tools of aquatic pollution biomonitoring. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 674–682, 2015.     

Relating the physicochemical characteristics and dispersion of multiwalled carbon nanotubes in different suspension media to their oxidative reactivity in vitro and inflammation in vivo

Abstract

Reactive oxygen species (ROS) production is important in the toxicity of pathogenic particles such as fibres. We examined the oxidative potential of straight (50 μm and 10 μm) and tangled carbon nanotubes in a cell free assay, in vitro and in vivo using different dispersants. The cell free oxidative potential of tangled nanotubes was higher than for the straight fibres. In cultured macrophages tangled tubes exhibited significantly more ROS at 30 min, while straight tubes increased ROS at 4 h. ROS was significantly higher in bronchoalveolar lavage cells of animals instilled with tangled and 10 μm straight fibres, whereas the number of neutrophils increased only in animals treated with the long tubes. Addition of dispersants in the suspension media lead to enhanced ROS detection by entangled tubes in the cell-free system. Tangled fibres generated more ROS in a cell-free system and in cultured cells, while straight fibres generated a slower but more prolonged effect in animals.     

艾拉莫德对脂多糖激活大鼠肺泡巨噬细胞系TNFα产生及NF-κB活性的抑制作用

目的研究非甾体抗炎药艾拉莫德(T-614)对脂多糖(LPS)刺激的大鼠肺泡巨噬细胞系(NR8383)前炎症反应因子TNFα基因表达、蛋白合成的影响及其对核因子κB(NF-κB)的作用。方法体外培养NR8383经T-614(13.4，26.7及53.4 μmol·L^-1)处理，LPS刺激后应用酶联免疫吸附法(ELISA)检测细胞上清液中TNFα的水平，半定量逆转录聚合酶链式反应(RT-PCR)检测TNFα mRNA水平，ELISA法检测NF-κB的活性。结果T-614对LPS诱导的NR8383细胞TNFα mRNA水平和蛋白水平的上调有显著抑制作用，对NF-κB的转录活性也有抑制作用。结论 T-614可能通过抑制LPS诱导的NR8383的NF-κB活性而降低TNFα的产生。