PDF(Pubmed)
Abstract：
Bulk zinc oxide (ZnO-BPs) and its nanoparticles (ZnO-NPs) are frequently used in various products for humans. Helisoma duryi embryos can serve as effective model organisms for studying the toxicity of NPs. This study aimed to compare the teratogenic potency of ZnO-BPs and ZnO NPs in the embryonic stages of H. duryi to evaluate the utility of this snail as a bioindicator for ZnO-NPs in the aquatic environment. The mechanisms of teratogenesis were evaluated by determination of the LC50, studying the effect of sub-lethal concentrations of both ZnO forms on the embryos, and studying their enzyme activity, oxidative stress, and biochemical analysis. The SDS-PAGE electrophoresis was undertaken to assess the effect of ZnO-BPs and ZnO NPs on protein synthesis. The results revealed that the veliger stage of H. duryi is the specific stage for bulk and nano ZnO. ZnO-NPs proved to be more toxic to snails\' embryos than ZnO-BPs. Exposure to ZnO influences specific types of defects in development, which in the case of BPs are far less drastic than those caused by NPs. Thus, the toxicity of ZnO-NPs in embryonic development is due to their unique physicochemical properties. The observed malformations include mainly hydropic malformation, exogastrulation, monophthalmia, shell misshapen, and cell lyses. Almost all tested oxidative biomarkers significantly changed, revealing that ZnONPs display more oxidative stress than ZnO-BPs. Also, the low concentration of ZnO induces many disturbances in the organic substances of veliger larvae, such as a decrease in the total protein and total lipid levels and an increase in the glycogen level. The results indicated that ZnO-BPs increase the number of protein bands. Conversely, ZnO-NPs concealed one band from treated egg masses, which was found in the control group. Embryos of snail are an appropriate model to control freshwater snails. This study demonstrates that H. duryi embryos can serve as effective model organisms to study the toxicity of ZnO-NPs.
摘要：
大量氧化锌（ZnO-BPs）及其纳米颗粒（ZnO-NPs）经常用于各种人类产品中。Helisomaduryi胚胎可以作为研究NPs毒性的有效模型生物。这项研究旨在比较ZnO-BPs和ZnONPs在H.duryi胚胎阶段的致畸效力，以评估这种蜗牛作为ZnO-NPs在水生环境中的生物指示剂的实用性。通过测定LC50，研究两种ZnO形式的亚致死浓度对胚胎的影响，评估了致畸机制。研究它们的酶活性，氧化应激，和生化分析。进行SDS-PAGE电泳以评估ZnO-BP和ZnONP对蛋白质合成的影响。结果表明，H.duryi的veliger阶段是块状和纳米ZnO的特定阶段。ZnO-NP对蜗牛胚胎的毒性比ZnO-BPs更大。暴露于ZnO会影响开发中特定类型的缺陷，在BP的情况下，远远没有由NP引起的剧烈程度。因此，ZnO-NP在胚胎发育中的毒性是由于其独特的理化性质。观察到的畸形主要包括积水畸形，外植体,单眼症,贝壳畸形，和细胞裂解。几乎所有测试的氧化生物标志物都发生了显著变化，表明ZnONPs比ZnO-BPs表现出更多的氧化应激。此外，低浓度的ZnO会对veliger幼虫的有机物质产生许多干扰，例如总蛋白质和总脂质水平的降低和糖原水平的增加。结果表明，ZnO-BPs增加了蛋白质条带的数量。相反，ZnO-NPs从处理的卵团中隐藏了一条带，在对照组中发现。蜗牛胚胎是控制淡水蜗牛的合适模型。这项研究表明H.duryi胚胎可以作为研究ZnO-NP毒性的有效模型生物。
