Imidacloprid (IMI) is a widely used neonicotinoid insecticide that has toxic effects on nontarget organisms. 1,8-Cineole (eucalyptol) is purified from essential oils in several aromatic plants and can prevent xenobiotic toxicity. The kidney is a major organ for xenobiotic elimination and thus has high risk of exposure. The purpose of this research was to clarify the effect of IMI exposure on autophagy in fish kidney cells, determine the potential of eucalyptol to provide cytoprotection from the toxicity of the neonicotinoid pesticide IMI, and identify its mechanism of action. Therefore, the Ctenopharyngodon idellus kidney cell line (CIK cell) was treated with 20 mg/L IMI and/or 20 μM eucalyptol for 48 h as the research objective. The results showed that IMI exposure induced autophagy accompanied by advanced autophagy markers BNIP3, Beclin1 and LC3Ⅱ/Ⅰ in CIK cells, reduced the levels of miR-451, increased the expression of Cab39 and AMPK, inhibited AKT/mTOR signaling, and activated the JNK pathway. Eucalyptol treatment alleviated IMI-induced autophagy and relieved the activation of autophagy-associated signals. These results indicate that eucalyptol could alleviate IMI-induced autophagy through the miR-451/Cab39/AMPK axis in fish kidney cells. These results partly explained the mechanism of biological threat on fish under IMI exposure and the potential application value of EUC in aquaculture.

吡虫啉 (IMI) 是一种广泛使用的新烟碱类杀虫剂，对非靶标生物具有毒性作用。1,8-桉树脑（桉树脑）是从几种芳香植物的精油中提纯出来的，可以防止外源性毒性。肾脏是消除外源性物质的主要器官，因此具有很高的暴露风险。本研究的目的是阐明 IMI 暴露对鱼肾细胞自噬的影响，确定桉树脑对新烟碱类农药 IMI 的毒性提供细胞保护的潜力，并确定其作用机制。因此，Ctenopharyngodon idellus肾细胞系（CIK 细胞）用 20 mg/L IMI 和/或 20 μM 桉树脑处理 48 h 作为研究目标。结果表明，IMI 暴露诱导 CIK 细胞自噬并伴有晚期自噬标志物 BNIP3、Beclin1 和 LC3Ⅱ/Ⅰ，降低 miR-451 水平，增加 Cab39 和 AMPK 表达，抑制 AKT/mTOR 信号，激活 JNK途径。Eucalyptol 治疗减轻了 IMI 诱导的自噬并减轻了自噬相关信号的激活。这些结果表明桉树油可以通过鱼肾细胞中的 miR-451/Cab39/AMPK 轴减轻 IMI 诱导的自噬。这些结果部分解释了IMI暴露对鱼类的生物威胁机制以及EUC在水产养殖中的潜在应用价值。