Nanopolystyrene (NP) pollution in aquatic environments has become an increasing concern. Phoxim (PHO), one of the major organophosphorus pesticides, has also been detected in aquatic environments, posing serious health risks to crustaceans. This study aimed to assess the detrimental effects of NP and/or PHO exposure at environmentally relevant concentrations on the intestinal histopathology, intestinal microbiota, and metabolome of adult crabs (Eriocheir sinensis) for 21 days. Our study revealed significant histopathological abnormalities in the intestines. In all the exposure groups, there was a discovery of vacuolar degeneration occurring in epithelial cells. Additionally, the peritrophic membrane exhibited thinning after NP or PHO single exposure, while thickening was observed after co-exposure. Exposure to NP and/or PHO disrupted the intestinal microbiota homeostasis, as evidenced by the proliferation of pathogenic bacteria and suppression of beneficial bacteria. Notably, PHO exposure resulted in increased abundance of pathogenic bacteria (Spiroplasma and Arcobacter) and decreased abundance of beneficial bacteria (Bacteroides). Analysis of the metabolome revealed that exposure to NP and/or PHO led to alterations in the metabolic profile as well as several critical pathways. Among these, the upregulation of arachidonic acid metabolism, ABC transporters, and biosynthesis of amino acids was observed in both NP single exposure and co-exposure, while PHO single exposure downregulated these pathways. Additionally, NP and/or PHO exposure downregulated neuroactive ligand-receptor interaction. Spearman correlation analysis revealed that the significant reduction of some differentially expressed metabolites (DEMs) was potentially regulated by the low-abundance bacterial genera following exposure to NP and/or PHO. And these DEMs have a role in anti-inflammatory or antioxidant properties. Collectively, our results offer novel perspectives on the intestinal toxicity of crustaceans by NP and/or PHO at environmentally relevant concentrations.

中文翻译：

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环境相关浓度的纳米聚苯乙烯和/或磷酰胺暴露对中华鳕鱼肠道组织病理学、肠道微生物群和代谢组的影响


水生环境中的纳米聚苯乙烯 （NP） 污染已成为一个日益受到关注的问题。磷化钾 （PHO） 是主要的有机磷杀虫剂之一，也在水生环境中被检测到，对甲壳类动物构成严重的健康风险。本研究旨在评估环境相关浓度的 NP 和/或 PHO 暴露对成年蟹 （Eriocheir sinensis） 肠道组织病理学、肠道微生物群和代谢组 21 天的不利影响。我们的研究揭示了肠道中显着的组织病理学异常。在所有暴露组中，都发现了上皮细胞中发生的液泡变性。此外，NP 或 PHO 单次暴露后周养膜变薄，而共暴露后观察到增厚。暴露于 NP 和/或 PHO 破坏了肠道微生物群稳态，病原菌的增殖和有益细菌的抑制证明了这一点。值得注意的是，PHO 暴露导致病原菌 （螺原体和弓杆菌） 的丰度增加，而有益细菌 （拟杆菌属） 的丰度降低。代谢组分析显示，暴露于 NP 和/或 PHO 会导致代谢特征以及几个关键途径的改变。其中，花生四烯酸代谢、ABC 转运蛋白和氨基酸生物合成的上调在 NP 单次暴露和共暴露中均观察到，而 PHO 单次暴露下调了这些途径。此外，NP 和/或 PHO 暴露下调了神经活性配体-受体相互作用。 Spearman 相关分析显示，暴露于 NP 和/或 PHO 后，一些差异表达代谢物 （DEM） 的显着减少可能受到低丰度细菌属的调节。这些 DEM 具有抗炎或抗氧化特性。总的来说，我们的结果为环境相关浓度下 NP 和/或 PHO 对甲壳类动物的肠道毒性提供了新的视角。