Abstract：
Silver nanoparticles (AgNPs) and Zinc oxide nanoparticles (ZnONPs) have been widely used and are eventually been discharged into the natural aquatic ecosystem. The current study examined and correlated the toxicity of AgNPs and ZnONPs on the Mozambique tilapia, Oreochromis mossambicus. Lethal concentration (LC50) was determined with four different concentrations (0.05, 0.10, 0.15, and 0.20 mg/L) of AgNPs and ZnONPs; subsequently, the fishes were exposed to sublethal concentrations for a period of 21 days, and the oxidative stress and antioxidant and nonantioxidant parameters were studied. Results revealed oxidative stress evinced by increased lipid peroxidation (LPO) protein carbonyl activity (PCA), glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) activity, metallothionein (MT) activity, and reduced glutathione in chronic exposure compared with acute exposure. Nonspecific immunological characteristics such as lysozyme (LYZ), myeloperoxidase (MPO), and respiratory burst activity (RBA) were also noticed in the serum. Furthermore, severe histological damages including damages in telangiectasia and epithelial cell hyperplasia were found in the combined treated group with Ag and ZnONPs than in individual treatments. When Ag and ZnONPs were combined, a reduction in the accumulation of Ag was observed in the liver, which increased drastically in individual exposure. The current findings highlight the importance of taking into account the combined exposure and correlation of NPs, their bioavailability, and toxicity in the aquatic ecosystem.
摘要：
银纳米粒子（AgNPs）和氧化锌纳米粒子（ZnONPs）已被广泛使用，并最终被排放到自然水生生态系统中。当前的研究检查了AgNPs和ZnONPs对莫桑比克罗非鱼的毒性并进行了关联，莫来氏细菌。使用四种不同浓度（0.05、0.10、0.15和0.20mg/L）的AgNPs和ZnONPs测定致死浓度（LC50）；随后，鱼暴露于亚致死浓度21天，并研究了氧化应激和抗氧化和非抗氧化参数。结果表明，氧化应激表现为脂质过氧化（LPO）蛋白羰基活性（PCA）增加，谷胱甘肽-S-转移酶（GST），谷胱甘肽过氧化物酶（GPx），超氧化物歧化酶（SOD），过氧化氢酶（CAT）活性，金属硫蛋白（MT）活性，与急性暴露相比，慢性暴露中的谷胱甘肽减少。非特异性免疫学特征，如溶菌酶（LYZ），髓过氧化物酶(MPO),在血清中也观察到呼吸爆发活动（RBA）。此外，与单独治疗相比,Ag和ZnONPs联合治疗组发现了严重的组织学损伤,包括毛细血管扩张和上皮细胞增生的损伤.当Ag和ZnONPs结合时，在肝脏中观察到Ag的积累减少，这在个体暴露中急剧增加。目前的调查结果强调了考虑NPs的综合暴露和相关性的重要性，它们的生物利用度，和水生生态系统中的毒性。
