Abstract：
Microplastics (MPs) have become pervasive in marine ecosystems, exerting detrimental effects on marine life. The concurrent presence and interaction of MPs and heavy metals in aquatic environments could engender more insidious toxicological impacts. This study aimed to elucidate the potential impacts and underlying mechanisms of polystyrene microplastics (PS-MPs), cadmium (Cd), and their combined stress (MPs-Cd) on sea cucumbers (Apostichopus japonicus). It focused on the growth, Cd bioaccumulation, oxidative stress responses, immunoenzymatic activities, and metabolic profiles, specifically considering PS-MPs sizes preferentially ingested by these organisms. The high-dose MPs (MH) treatment group exhibited an increase in cadmium bioavailability within the sea cucumbers. Exposure to PS-MPs or Cd triggered the activation of antioxidant defenses and immune responses. PS-MPs and Cd exhibited a synergistic effect on lysozyme (LZM) activity. A total of 149, 316, 211, 197, 215, 619, 434, and 602 differentially expressed metabolites were identified, distinguishing the low-dose MPs (ML), high-dose MPs (MH), low-dose Cd (LCd), low-dose MPs and low-dose Cd (MLLCd), high-dose MPs and low-dose Cd (MHLCd), high-dose Cd (HCd), low-dose MPs and high-dose Cd (MLHCd), high-dose MPs and high-dose Cd (MHHCd) groups, respectively. Metabolomic analyses revealed disruptions in lipid metabolism, nervous system function, signal transduction, and transport and catabolism pathways following exposure to PS-MPs, Cd, and MPs-Cd. Correlation analyses among key differentially expressed metabolites (DEMs) underscored the interregulation among these metabolic pathways. These results offer new perspectives on the distinct and synergistic toxicological impacts of microplastics and cadmium on aquatic species, highlighting the complex interplay between environmental contaminants and their effects on marine life.
摘要：
微塑料（MPs）已经在海洋生态系统中普遍存在，对海洋生物产生有害影响。MPs和重金属在水生环境中的同时存在和相互作用可能会产生更阴险的毒理学影响。本研究旨在阐明聚苯乙烯微塑料（PS-MPs）的潜在影响和潜在机制，镉(Cd),以及它们对海参（刺参）的联合胁迫（MPs-Cd）。它专注于增长，Cd生物累积,氧化应激反应，免疫酶活性，和代谢概况，特别是考虑这些生物优先摄入的PS-MPs大小。高剂量MPs（MH）治疗组显示海参中镉的生物利用度增加。暴露于PS-MPs或Cd会触发抗氧化防御和免疫反应的激活。PS-MPs和Cd对溶菌酶（LZM）活性具有协同作用。总共鉴定了149、316、211、197、215、619、434和602种差异表达的代谢物，区分低剂量MP(ML)，高剂量MP（MH），低剂量Cd(LCd),低剂量MPs和低剂量Cd（MLLCd），高剂量MPs和低剂量Cd（MHLCd），高剂量Cd(HCd)，低剂量MP和高剂量Cd（MLHCd），高剂量MPs和高剂量Cd(MHHCd)组，分别。代谢组学分析显示脂质代谢中断，神经系统功能,信号转导，以及暴露于PS-MPs后的运输和分解代谢途径，Cd,和MP-Cd。关键差异表达代谢物（DEM）之间的相关性分析强调了这些代谢途径之间的相互调节。这些结果为微塑料和镉对水生物种的独特和协同毒理学影响提供了新的视角。强调环境污染物及其对海洋生物的影响之间复杂的相互作用。
