Fisheries Science Institute, Chonnam National University, Yeosu 59626, South Korea.
Fisheries Science Institute, Chonnam National University, Yeosu 59626, South Korea; Department of Ocean Integrated Science, Chonnam National University, Yeosu 59626, South Korea.
Sci Total Environ. 2022 Oct 10;842:156555. doi: 10.1016/j.scitotenv.2022.156555. Epub 2022 Jun 21.
Global warming is causing a continuous increase in environmental temperatures, which simultaneously activates toxic environmental stresses, such as heavy metal exposure, in aquatic ecosystems. The present study aimed at evaluating the effects of Cu toxicity along with increased temperature during zebrafish embryogenesis. Decreased survival rates were observed following combined exposure to high temperature and Cu. Heart rates of zebrafish embryos were significantly increased only during heat stress. An abnormal morphology with curved body shape was induced by exposure to a combination of Cu and heat stress. Furthermore, heat stress also triggered Cu-induced intracellular reactive oxygen species (ROS) production, with upregulation of superoxide dismutase (SOD) and glutathione s-transferase (GST) expression, and cell death with modified expression of p53 and B-cell lymphoma-2 (Bcl-2) in zebrafish embryos. Finally, increased cortisol levels and altered expression of cortisol-signaling genes were observed following exposure to Cu and high temperatures. These results highlight that realistic exposure to combined stressors induces developmental disturbances via stress-induced responses involving oxidative stress and cell death as well as transcriptional alterations leading to cortisol signaling in fish.
全球变暖导致环境温度持续升高，同时激活了水生生态系统中的有毒环境压力，如重金属暴露。本研究旨在评估高温和 Cu 毒性对斑马鱼胚胎发育的影响。高温和 Cu 联合暴露后，存活率下降。仅在热应激时，斑马鱼胚胎的心率显著增加。暴露于 Cu 和热应激的联合作用会导致身体弯曲的异常形态。此外，热应激还会引发 Cu 诱导的细胞内活性氧（ROS）产生，上调超氧化物歧化酶（SOD）和谷胱甘肽 S-转移酶（GST）的表达，并改变 p53 和 B 细胞淋巴瘤-2（Bcl-2）的表达，导致斑马鱼胚胎死亡。最后，暴露于 Cu 和高温后，皮质醇水平升高，皮质醇信号基因表达改变。这些结果表明，现实暴露于联合胁迫会通过涉及氧化应激和细胞死亡的应激诱导反应以及导致鱼类皮质醇信号的转录改变，引起发育障碍。
