School of Engineering, China Pharmaceutical University, Nanjing 210009, China.
State Key Laboratory for Environmental Protection of Water Ecological Health in the Middle and Lower Reaches of the Yangtze River, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China.
Sci Total Environ. 2024 Oct 20;948:174959. doi: 10.1016/j.scitotenv.2024.174959. Epub 2024 Jul 24.
High ammonia pollution is a common problem in water bodies. However, research on the mechanisms underlying the toxic effects on organisms at different nutritional levels is still insufficient. Herein, based on the environmental concentration, the toxic effects of high ammonia pollution on Daphnia magna were investigated. Overall, the feeding and filtration rates of D. magna were significantly decreased by ammonia. Growth inhibition of D. magna by ammonia was confirmed by the decreased body length. After ammonia exposure, the metabolic status of D. magna changed, the correlation network weakened, and the correlations between metabolites were disrupted. Changes occurred in metabolites primarily involved in oxidative stress, fatty acid oxidation, tricarboxylic acid cycle, and protein digestion, absorption, and synthesis, which were validated through alterations in multiple biomarkers. In addition, mitochondrial function was evaluated and was found to inhibit mitochondrial activity, which was accompanied by a decreased marker of mitochondrial activity contents and ATPase activity. Thus, the results suggested that energy metabolism and oxidative stress were involved in ammonia-induced growth toxicity. This study provides new insights into the impact of ammonia on aquatic ecological health.
高氨污染是水体中常见的问题。然而，对于不同营养水平的生物体受其毒性影响的机制研究仍不够充分。在此，基于环境浓度，研究了高氨污染对大型溞的毒性作用。总体而言，氨显著降低了大型溞的摄食和滤水率。氨对大型溞的生长抑制作用通过体长的减少得到了证实。暴露于氨后，大型溞的代谢状态发生改变，相关网络减弱，代谢物之间的相关性被打破。代谢物的变化主要涉及氧化应激、脂肪酸氧化、三羧酸循环和蛋白质消化、吸收和合成，这通过多个生物标志物的改变得到了验证。此外，还评估了线粒体功能，发现其抑制了线粒体活性，伴随着线粒体活性含量和 ATP 酶活性的标志物降低。因此，研究结果表明，能量代谢和氧化应激参与了氨引起的生长毒性。本研究为氨对水生生态健康的影响提供了新的见解。
