College of Geography and Environment, Shandong Normal University, Jinan 250000, China.
College of Geography and Environment, Shandong Normal University, Jinan 250000, China.
Ecotoxicol Environ Saf. 2023 Mar 15;253:114700. doi: 10.1016/j.ecoenv.2023.114700. Epub 2023 Feb 28.
Naphthenic acids (NAs) are typical contaminants in heavily crude oil. Benzo[a]pyrene (B[a]P) is also a component of crude oil, but their combined effects have not been systematically explored. In this study, zebrafish (Danio rerio) were used as the test organisms, and behavioral indicators and enzyme activities were used as toxicity indicators. Combined with the effects of environmental concentrations, the toxic effects of low concentrations of commercially available NAs (0.5 mg/LNA) and benzo[a]pyrene (0.8 μg/LBaP) at single and compound exposures (0.5 mg/LNA and 0.8 μg/LBaP) were assayed in zebrafish, and transcriptome sequencing technology was used to explore the molecular mechanism of the two compounds affecting zebrafish from the molecular biology level. Sensitive molecular markers that could indicate the presence of contaminants were screened. The results showed that (1) zebrafish in the NA and BaP exposure groups exhibited increased locomotor behavior, and the mixed exposure group exhibited inhibition of locomotor behavior. Oxidative stress biomarkers showed increased activity under single exposure and decreased activity under the mixed exposure. (2) NA stress led to changes in the activity of transporters and the intensity of energy metabolism; BaP directly stimulates the pathway of actin production. When the two compounds are combined, the excitability of neurons in the central nervous system is decreased, and the actin-related genes are down-regulated. (3) After BaP and Mix treatments, genes were enriched in the cytokine-receptor interaction and actin signal pathway, while NA increased the toxic effect on the mixed treatment group. In general, the interaction between NA and BaP has a synergistic effect on the transcription of zebrafish nerve and motor behavior-related genes, resulting in increased toxicity under combined exposure. The changes in expression of various zebrafish genes are manifested in the changes in the normal movement behavior of zebrafish and the intensification of oxidative stress in the apparent behavior and physiological indicators. CAPSULE ABSTRACT: We investigated the toxicity and genetic alterations caused by NA, B[a]P, and their mixtures in zebrafish in an aquatic environment using transcriptome sequencing technology and comprehensive behavioral analysis. These changes involved energy metabolism, the generation of muscle cells, and the nervous system.
萘酸（NA）是重油中典型的污染物。苯并[a]芘（B[a]P）也是原油的成分之一，但它们的联合效应尚未得到系统研究。在这项研究中，斑马鱼（Danio rerio）被用作测试生物，并将行为指标和酶活性用作毒性指标。结合环境浓度的影响，在单一和复合暴露（0.5 mg/LNA 和 0.8 μg/LBaP）下，检测了市售的低浓度的 NA（0.5 mg/LNA）和苯并[a]芘（0.8 μg/LBaP）对斑马鱼的毒性作用，并使用转录组测序技术从分子生物学水平探索了两种化合物影响斑马鱼的分子机制。筛选出可以指示污染物存在的敏感分子标记物。结果表明：（1）在 NA 和 BaP 暴露组中，斑马鱼的运动行为增加，而混合暴露组的运动行为受到抑制。单一暴露时，氧化应激生物标志物的活性增加，而混合暴露时的活性降低。（2）NA 应激导致转运蛋白活性和能量代谢强度发生变化；BaP 直接刺激肌动蛋白产生途径。当两种化合物结合时，中枢神经系统神经元的兴奋性降低，肌动蛋白相关基因下调。（3）BaP 和 Mix 处理后，基因在细胞因子受体相互作用和肌动蛋白信号通路中富集，而 NA 增加了混合处理组的毒性。一般来说，NA 和 BaP 的相互作用对斑马鱼神经和运动行为相关基因的转录具有协同作用，导致联合暴露时毒性增加。各种斑马鱼基因的表达变化表现在斑马鱼正常运动行为的变化以及明显行为和生理指标中氧化应激的加剧。
