4-tert-butylphenol (4-tBP) is a toxic environmental pollutant with moderate bioaccumulation, environmental persistence, and long-term toxicity. Its toxicity to aquatic organisms has become an issue of concern. However, the molecular mechanism of 4-tBP toxicity to aquatic organisms remained unclear. Liver is a target organ for environmental pollutants. Here, we established 4-tBP-exposed toxicity model in vivo and primary hepatocyte model in vitro in common carp (Cyprinus carpio L.). We found increased hepatic-somatic index (HSI) and abnormal serum biochemical indexes (ALT, AST, and LDH) after 4-tBP exposure, indicating liver damage. We further revealed that 4-tBP damaged the structural integrity of the livers with typical features of ferroptosis. Based on toxicogenomics analysis, we found ferroptosis is likely to be involved in the mechanism of 4-tBP-induced liver damage. Moreover, our in vivo and in vitro experiment provided evidences that 4-tBP-exposure led to excess oxidative stress, iron overload, decreased MMP, and abnormal expression of ferroptosis-related factors. Interestingly, ferrostatin-1 (Fer-1, a ferroptosis inhibitor) pretreatment alleviated above changes. In summary, we demonstrated that 4-tBP triggered hepatocytes ferroptosis via oxidative stress, iron overload, SLC7A11/GSH/GPX4 axis, and ATF4/HSPA5/GPX4 axis. For the first time, we discovered that Fer-1 can ameliorate the toxicity of 4-tBP, which needs more investigations. Our results provided a scientific basis of molecular mechanism of 4-tBP-induced fish poisoning.

4-叔丁基苯酚 (4-tBP) 是一种有毒的环境污染物，具有中等生物累积性、环境持久性和长期毒性。其对水生生物的毒性已成为人们关注的问题。然而，4-tBP 对水生生物毒性的分子机制仍不清楚。肝脏是环境污染物的靶器官。在这里，我们在鲤鱼（Cyprinus carpioL.)。我们发现在 4 tBP 暴露后肝体指数 (HSI) 和血清生化指数异常 (ALT、AST 和 LDH) 升高，表明肝损伤。我们进一步揭示了 4-tBP 破坏了具有典型铁死亡特征的肝脏结构完整性。基于毒物基因组学分析，我们发现铁死亡可能与4-tBP诱导的肝损伤机制有关。此外，我们的体内和体外实验提供的证据表明，4-tBP 暴露导致过度氧化应激、铁过载、MMP 降低和铁死亡相关因子的异常表达。有趣的是，ferrostatin-1（Fer-1，一种铁死亡抑制剂）预处理减轻了上述变化。总之，我们证明了 4-tBP 通过氧化应激、铁过载、SLC7A11/GSH/GPX4 轴、和 ATF4/HSPA5/GPX4 轴。我们第一次发现Fer-1可以改善4-tBP的毒性，这需要更多的研究。我们的研究结果为 4-tBP 致鱼中毒的分子机制提供了科学依据。