Nataraj Bojan, Maharajan Kannan, Malafaia Guilherme, Hemalatha Devan, Ahmed Mohamed Ahmed Ibrahim, Ramesh Mathan
Unit of Toxicology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore 641046, India.
Unit of Toxicology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore 641046, India; Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), 28789 East Jingshi Road, Jinan 250103, Shandong Province, PR China.
Sci Total Environ. 2022 Jun 20;826:154046. doi: 10.1016/j.scitotenv.2022.154046. Epub 2022 Feb 23.
In recent decades, the ecotoxicological potential of organic ultraviolet filters (OU-VFs) has received growing attention. However, the toxicity of its photoproducts or transformation products on freshwater vertebrates has been little explored. Therefore, the aim of the present study is to evaluate the possible adverse effects of ethylhexyl methoxycinnamate (EHMC) and its photoproducts [2-ethylhexanol (2-EH) and 4-methoxybenzaldehyde (4-MBA)] on the expression of stress-responsive and antioxidant genes. For this, zebrafish (Danio rerio) adults were exposed to pollutants at an environmentally relevant concentration (3 μg/L) and evaluated after 7, 14, and 21 days of exposure. The results of the principal component analysis (PCA) and two-way repeated measures (RM) ANOVA revealed that EHMC, 2-EH, and 4-MBA exposure caused significant downregulation of the genes hsp70, nrf2, cyp1a, ahr, sod1, sod2, cat, gstp1, gpx1a, gss, and gsr (on all trial days) in the liver of the animals. On the other hand, taken together, our data did not show significant differences between the effects induced by EHMC and its photoproducts. The genes evaluated in the present study play a major role in regulating the defensive antioxidant response against EHMC and its photoproducts. Additionally, our study provides an insight into the mechanisms of those OU-VFs in freshwater fish.
近几十年来，有机紫外线过滤剂（OU-VFs）的生态毒理学潜力受到了越来越多的关注。然而，其光产物或转化产物对淡水脊椎动物的毒性却鲜有研究。因此，本研究的目的是评估桂皮酸盐（EHMC）及其光产物[2-乙基己醇（2-EH）和4-甲氧基苯甲醛（4-MBA）]对压力响应和抗氧化基因表达的可能不利影响。为此，将成年斑马鱼（Danio rerio）暴露于环境相关浓度（3μg/L）的污染物中，并在暴露7、14和21天后进行评估。主成分分析（PCA）和双向重复测量（RM）方差分析的结果显示，暴露于EHMC、2-EH和4-MBA会导致动物肝脏中hsp70、nrf2、cyp1a、ahr、sod1、sod2、cat、gstp1、gpx1a、gss和gsr基因（在所有试验天数）显著下调。另一方面，综合来看，我们的数据并未显示EHMC及其光产物所诱导的效应之间存在显著差异。本研究中评估的基因在调节针对EHMC及其光产物的防御性抗氧化反应中起主要作用。此外，我们的研究深入了解了这些OU-VFs在淡水鱼中的作用机制。
