Gut toxicity of polystyrene microplastics and polychlorinated biphenyls to Eisenia fetida: Single and co-exposure effects with a focus on links between gut bacteria and bacterial translocation stemming from gut barrier damage
Gut toxicity of polystyrene microplastics and polychlorinated biphenyls to Eisenia fetida: Single and co-exposure effects with a focus on links between gut bacteria and bacterial translocation stemming from gut barrier damage
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DOI：
10.1016/j.scitotenv.2023.168254
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发表时间：
2023-11-11
影响因子：
9.8
通讯作者：
Wu，Shijin
中科院分区：
文献类型：
--
作者：
Li，Tongtong;Xu，Baohua;Wu，Shijin
微塑料（MP）在土壤生态系统中吸附和迁移多氯联苯（PCBs）的能力值得关注。虽然生物体主要通过肠道接触污染物，但多氯联苯和多氯联苯对土壤动物肠道毒性的综合污染影响仍不完全清楚。因此，本研究考察了聚苯乙烯MP（PS-MP）和PCB 126对赤子爱胜蚓的肠道毒性，强调了肠道细菌和肠道屏障受损引起的细菌移位之间的联系。我们的研究结果强调了E.结果表明，PCB 126在E.病死率9.43%。暴露于PCB 126抑制肠紧密连接（TJ）蛋白基因的表达。虽然PS-MP的存在减弱了这种抑制，但它并没有减轻联合暴露组中肠道屏障损伤和细菌移位。该组的肠道细菌负荷（BLT，方差分析，p= 0.005，与对照组相比）和脂多糖结合蛋白（LBP，方差分析，allp< 0.001，与对照组、PCB和PS组相比）水平显着增加，这两者都显示出显着的正相关性与抗菌防御。此外，暴露于PS-MP和PCB 126，特别是在共同暴露组中，导致肠道细菌的扩散能力显著下降。这导致了生态失调（Adonis，R2= 0.294，p = 0.001），其中显著的特征分类群如Janthinobacterium、Microbacterium和Pseudomonas与肠道屏障功能障碍有关。本研究揭示了多氯联苯和多氯联苯复合污染对蚯蚓肠道毒性的作用机制，为土壤生态风险评价提供了新的思路。
Microplastics' (MPs) ability to sorb and transport polychlorinated biphenyls (PCBs) in soil ecosystems warrants significant attention. Although organisms mainly encounter pollutants through the gut, the combined pollution impact of MPs and PCBs on soil fauna gut toxicity remains incompletely understood. Consequently, this study examined the gut toxicity of polystyrene MPs (PS-MPs) and PCB126 on Eisenia fetida, emphasizing the links between gut bacteria and bacterial translocation instigated by gut barrier impairment. Our findings underscored thatE. fetidacould ingest PS-MPs, which mitigated the PCB126 accumulation inE. fetidaby 9.43 %. Exposure to PCB126 inhibited the expression of gut tight junction (TJ) protein genes. Although the presence of PS-MPs attenuated this suppression, it didn't alleviate gut barrier damage and bacterial translocation in the co-exposure group. This group demonstrated a significantly increased level of gut bacterial load (BLT, ANOVA,p= 0.005 vs control group) and lipopolysaccharide-binding protein (LBP, ANOVA, allp< 0.001 vs control, PCB, and PS groups), both of which displayed significant positive correlations with antibacterial defense. Furthermore, exposure to PS-MPs and PCB126, particularly within the co-exposure group, results in a marked decline in the dispersal ability of gut bacteria. This leads to dysbiosis (Adonis, R2= 0.294,p= 0.001), with remarkable signature taxa such as Janthinobacterium, Microbacterium and Pseudomonas, being implicated in gut barrier dysfunction. This research illuminates the mechanism of gut toxicity induced by PS-MPs and PCB126 combined pollution in earthworms, providing novel insights for the ecological risk assessment of soil.