Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany.
Department of Plant Physiology, Institute for Biological Sciences, University of Rostock, Rostock, Germany.
Sci Total Environ. 2023 Feb 1;858(Pt 2):160039. doi: 10.1016/j.scitotenv.2022.160039. Epub 2022 Nov 8.
Nanopollutants such as nZnO gain importance as contaminants of emerging concern due to their high production volume and potential toxicity. Coastal sediments serve as sinks for nanoparticles but the impacts and the toxicity mechanisms of nZnO in sediment-dwelling organisms are not well understood. We used metabolomics to assess the effects of nZnO-contaminated sediments on a benthic ecosystem engineer, an infaunal polychaete Arenicola marina. The worms were exposed to unpolluted (control) sediment or to the sediment spiked with 100 or 1000 μg Zn kg of nZnO. Oxidative lesions (lipid peroxidation and protein carbonyls) were measured in the body wall as traditional biomarkers of nanopollutant toxicity. Metabolite profiles (including amino acids, tricarboxylic acid (TCA) cycle and urea cycle intermediates) were determined in the body wall and the coelomic fluid. Exposure to nZnO altered metabolism of the lugworms via suppression of the metabolism of gluconeogenic and aromatic amino acids, and altered the TCA cycle likely via suppression of fumarase activity. These metabolic changes may negatively affect carbohydrate metabolism and energy storage, and impair hormonal signaling in the worms. The total pool of free amino acids was depleted in nZnO exposures with potentially negative consequences for osmoregulation and protein synthesis. Exposure to nZnO led to accumulation of the lipid peroxidation products demonstrating high susceptibility of the cellular membranes to nZnO-induced oxidative stress. The nZnO-induced shifts in the metabolite profiles were more pronounced in the coelomic fluid than the body wall. This finding emphasizes the important metabolic role of the coelomic fluid as well as its suitability for assessing the toxic impacts of nZnO and other metabolic disruptors. The metabolic disruptions caused by environmentally relevant concentrations of nZnO can have negative effects on the organisms' fitness impairing growth and reproduction of the populations of marine bioturbators like the lugworms in nanoparticle-polluted sediments.
纳米污染物（如 nZnO）由于其高产量和潜在毒性而成为新兴关注的污染物。沿海沉积物是纳米颗粒的汇，但 nZnO 对沉积物生物的影响和毒性机制尚不清楚。我们使用代谢组学来评估受 nZnO 污染的沉积物对底栖生态工程师（一种穴居多毛类环节动物）的影响。这些蠕虫暴露于未受污染的（对照）沉积物或添加了 100 或 1000μg Zn/kg nZnO 的沉积物中。在体壁中测量氧化损伤（脂质过氧化和蛋白质羰基）作为纳米污染物毒性的传统生物标志物。在体壁和体腔液中测定代谢物谱（包括氨基酸、三羧酸 (TCA) 循环和尿素循环中间产物）。暴露于 nZnO 通过抑制糖异生和芳香族氨基酸的代谢来改变环节动物的代谢，并且可能通过抑制延胡索酸酶活性来改变 TCA 循环。这些代谢变化可能会对碳水化合物代谢和能量储存产生负面影响，并损害蠕虫中的激素信号。nZnO 暴露会耗尽游离氨基酸的总池，可能对渗透压和蛋白质合成产生负面影响。暴露于 nZnO 导致脂质过氧化产物的积累，表明细胞膜对 nZnO 诱导的氧化应激高度敏感。与体壁相比，nZnO 诱导的代谢物谱变化在体腔液中更为明显。这一发现强调了体腔液作为评估 nZnO 和其他代谢干扰物毒性影响的重要代谢作用以及其适宜性。与环境相关浓度的 nZnO 引起的代谢干扰会对生物体的适应性产生负面影响，从而损害受纳米颗粒污染的沉积物中海洋生物搅动者（如环节动物）的种群生长和繁殖。
