Wang Pu, Zhao Li-Hong, Zhu Xiao-Shan
Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
School of Environment, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue. 2021 Sep 8;42(9):4350-4357. doi: 10.13227/j.hjkx.202101078.
The release of manufactured nanomaterials (MNMs) into the environment has raised concerns about combined toxicological risks, as MNMs could significantly alter the environmental behavior and fate of co-existing contaminants. Numerous studies have been published on the combined toxicity of MNMs and co-existing contaminants, but the potential mechanisms controlling the combined toxicity, especially the biological response mechanism, remain unclear. This study investigated the combined toxicity of nano-titanium dioxide (nTiO), a typical MNM, and the heavy metal cadmium (Cd), using as the test organism. The molecular mechanism was examined under different concentrations, using an equivalent dose (toxic ratio 1 ∶1) on . The results showed that the 72h-EC of nTiO and Cd at the equivalent dose was significantly higher than that of single exposure, indicating an antagonistic effect. Further transcriptomics analysis revealed that the photosynthesis, chlorophyll metabolism, and starch and sucrose metabolism pathways involved in the energy metabolism of were significantly up-regulated in the presence of nTiO. The arginine and proline metabolic pathways related to the anti-stress effect of algae cells also showed positive stimulation. The results of this study provide an important reference and a research basis for in-depth understanding of the environmental effects of MNMs and co-existing contaminants.
人造纳米材料（MNMs）释放到环境中引发了对联合毒理学风险的担忧，因为MNMs可能会显著改变共存污染物的环境行为和归宿。关于MNMs与共存污染物的联合毒性已经发表了大量研究，但控制联合毒性的潜在机制，尤其是生物反应机制，仍不清楚。本研究以 为受试生物，研究了典型的MNM纳米二氧化钛（nTiO）与重金属镉（Cd）的联合毒性。在不同浓度下，使用等效剂量（毒性比1∶1）对 进行检测，研究其分子机制。结果表明，在等效剂量下，nTiO和Cd的72小时半数效应浓度（EC）显著高于单次暴露，表明存在拮抗作用。进一步的转录组学分析表明，在nTiO存在的情况下， 能量代谢中涉及的光合作用、叶绿素代谢以及淀粉和蔗糖代谢途径显著上调。与藻类细胞抗应激作用相关的精氨酸和脯氨酸代谢途径也表现出正向刺激。本研究结果为深入了解MNMs与共存污染物的环境影响提供了重要参考和研究基础。
