Abstract：
Polypropylene microplastics (PP-MPs) are emerging pollutant commonly detected in various environmental matrices and organisms, while their adverse effects and mechanisms are not well known. Here, zebrafish embryos were exposed to environmentally relevant concentrations of PP-MPs (0.08-50 mg/L) from 2 h post-fertilization (hpf) until 120 hpf. The results showed that the body weight was increased at 2 mg/L, heart rate was reduced at 0.08 and 10 mg/L, and behaviors were impaired at 0.4, 10 or 50 mg/L. Subsequently, transcriptomic analysis in the 0.4 and 50 mg/L PP-MPs treatment groups indicated potential inhibition on the glycolysis/gluconeogenesis and oxidative phosphorylation pathways. These findings were validated through alterations in multiple biomarkers related to glucose metabolism. Moreover, abnormal mitochondrial ultrastructures were observed in the intestine and liver in 0.4 and 50 mg/L PP-MPs treatment groups, accompanied by significant decreases in the activities of four mitochondrial electron transport chain complexes and ATP contents. Oxidative stress was also induced, as indicated by significantly increased ROS levels and significant reduced activities of CAT and SOD and GSH contents. All the results suggested that environmentally relevant concentrations of PP-MPs could induce disrupted mitochondrial energy metabolism in zebrafish, which may be associated with the observed behavioral impairments. This study will provide novel insights into PP-MPs-induced adverse effects and highlight need for further research.
摘要：
聚丙烯微塑料(PP-MPs)是在各种环境基质和生物体中常见的新兴污染物,虽然它们的副作用和机制尚不清楚。这里,从受精后2小时（hpf）到120hpf，斑马鱼胚胎暴露于环境相关浓度的PP-MPs（0.08-50mg/L）。结果表明，体重在2mg/L时增加，心率在0.08和10mg/L时降低，行为在0.4、10或50mg/L时受损。随后，在0.4和50mg/LPP-MPs治疗组中的转录组学分析显示对糖酵解/糖异生和氧化磷酸化途径的潜在抑制。这些发现通过与葡萄糖代谢相关的多种生物标志物的改变得到了验证。此外，0.4和50mg/LPP-MPs治疗组肠道和肝脏线粒体超微结构异常,伴随着四个线粒体电子传递链复合物的活性和ATP含量的显着降低。氧化应激也被诱导，如显着增加的ROS水平和显着降低的CAT和SOD和GSH含量的活性所示。所有结果表明，环境相关浓度的PP-MPs可以诱导斑马鱼线粒体能量代谢中断，这可能与观察到的行为障碍有关。这项研究将为PP-MPs引起的不良反应提供新的见解，并强调需要进一步研究。
