Teng Miaomiao, Zhao Xiaoli, Wu Fengchang, Wang Chengju, Wang Chen, White Jason C, Zhao Wentian, Zhou Lingfeng, Yan Sen, Tian Sinuo
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Environ Int. 2022 May;163:107154. doi: 10.1016/j.envint.2022.107154. Epub 2022 Mar 22.
Nanoplastics are being detected with increasing frequency in aquatic environments. Although evidence suggests that nanoplastics can cause overt toxicity to biota across different trophic levels, but there is little understanding of how materials such as differently charged polystyrene nanoplastics (PS-NP) impact fish development and behavior. Following exposure to amino-modified (positive charge) PS-NP, fluorescence accumulation was observed in the zebrafish brain and gastrointestinal tract. Positively charged PS-NP induced stronger developmental toxicity (decreased spontaneous movement, heartbeat, hatching rate, and length) and cell apoptosis in the brain and induced greater neurobehavioral impairment as compared to carboxyl-modified (negative charge) PS-NP. These findings correlated well with fluorescence differences indicating PS-NP presence. Targeted neuro-metabolite analysis by UHPLC-MS/MS reveals that positively charged PS-NP decreased levels of glycine, cysteine, glutathione, and glutamic acid, while the increased levels of spermine, spermidine, and tyramine were induced by negatively charged PS-NP. Positively charged PS-NP interacted with the neurotransmitter receptor N-methyl-D-aspartate receptor 2B (NMDA2B), whereas negatively charged PS-NP impacted the G-protein-coupled receptor 1 (GPR1), each with different binding energies that led to behavioral differences. These findings reveal the charge-specific toxicity of nanoplastics to fish and provide new perspective for understanding PS-NP neurotoxicity that is needed to accurately assess potential environmental and health risks of these emerging contaminants.
在水生环境中，纳米塑料的检出频率越来越高。尽管有证据表明纳米塑料会对不同营养级的生物群造成明显毒性，但对于诸如带不同电荷的聚苯乙烯纳米塑料（PS-NP）等材料如何影响鱼类发育和行为，人们了解甚少。在暴露于氨基修饰（带正电荷）的PS-NP后，在斑马鱼的大脑和胃肠道中观察到荧光积累。与羧基修饰（带负电荷）的PS-NP相比，带正电荷的PS-NP诱导更强的发育毒性（自发运动、心跳、孵化率和体长降低）以及大脑中的细胞凋亡，并导致更大的神经行为损伤。这些发现与表明PS-NP存在的荧光差异密切相关。通过超高效液相色谱-串联质谱（UHPLC-MS/MS）进行的靶向神经代谢物分析表明，带正电荷的PS-NP降低了甘氨酸、半胱氨酸、谷胱甘肽和谷氨酸的水平，而带负电荷的PS-NP则诱导了精胺、亚精胺和酪胺水平的升高。带正电荷的PS-NP与神经递质受体N-甲基-D-天冬氨酸受体2B（NMDA2B）相互作用，而带负电荷的PS-NP影响G蛋白偶联受体1（GPR1），它们各自具有不同的结合能，导致行为差异。这些发现揭示了纳米塑料对鱼类的电荷特异性毒性，并为理解PS-NP神经毒性提供了新的视角，这对于准确评估这些新兴污染物的潜在环境和健康风险是必要的。
