Abstract

The levels of the chlorinated organic compound Dechlorane Plus (DP) are increasing in aquatic ecosystems. To investigate the adverse effects of DP on aquatic animals, common carp (Cyprinus carpio) were subjected to three different DP concentrations (30 μg L⁻¹, 60 μg L⁻¹, and 120 μg L⁻¹) for 1 d, 15 d, and 30 d. Histology and the hepatic and cerebral expression levels of several key antioxidant, detoxification, and apoptotic factors were then examined. Histopathological inspections showed that the liver and brain were severely damaged in carp exposed to 60 μg L⁻¹ and 120 μg L⁻¹ DP. Relative to the controls, the superoxide dismutase and glutathione activity levels and the malondialdehyde content were also changed in livers and brains exposed to DP. Besides, significant alterations in the expression levels of the inflammatory cytokines IL-1β, IL-6, and IL-10 were observed in the livers of carp subjected to DP. Relative to the control, the brains of DP-exposed carp presented with significantly upregulated IL-1β and IL-6 in carp treated with 120 μg L⁻¹ DP for 30 d. The transcription levels of hepatic cyp2b4, cyp1b1, and cyp3a138 were all increased compared with the untreated at all DP exposure concentrations. The aforementioned results suggest that DP exposure perturbs fish metabolism and causes liver injury by inhibiting antioxidant enzyme activity, increasing lipid peroxidation, promoting inflammation, and inducing cell apoptosis. This information and the analytical methodology used to acquire it may form the basis for future ecological risk assessments on DP and related xenobiotics in aquatic animals.

摘要

水生生态系统中氯化有机化合物 Dechlorane Plus (DP) 的含量正在增加。为了研究 DP 对水生动物的不利影响，对鲤鱼 ( Cyprinus carpio ) 进行了三种不同 DP 浓度（30 μg L ^-1、60 μg L ^-1和 120 μg L ^-1）的处理 1 d、15 d , 和 30 天。然后检查了几种关键抗氧化剂、解毒和凋亡因子的组织学和肝和脑表达水平。组织病理学检查表明，在暴露于 60 μg L ^-1和 120 μg L ^{-1的鲤鱼中，肝脏和大脑严重受损}DP。相对于对照组，暴露于 DP 的肝脏和大脑中的超氧化物歧化酶和谷胱甘肽活性水平以及丙二醛含量也发生了变化。此外，在经DP处理的鲤鱼肝脏中观察到炎性细胞因子IL-1β、IL-6和IL-10的表达水平发生显着变化。相对于对照，在用120 μg L ^-1 DP 处理30 d的鲤鱼中，暴露于DP 的鲤鱼的脑中IL-1β和IL-6显着上调。肝cyp2b4、cyp1b1和cyp3a138的转录水平在所有 DP 暴露浓度下，与未处理的相比，均有所增加。上述结果表明，DP暴露通过抑制抗氧化酶活性、增加脂质过氧化、促进炎症和诱导细胞凋亡来扰乱鱼类代谢并导致肝损伤。这些信息和用于获取它的分析方法可能构成未来对水生动物中 DP 和相关异生素进行生态风险评估的基础。