Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China; Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China.
Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China; Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China.
J Hazard Mater. 2018 Oct 5;359:338-347. doi: 10.1016/j.jhazmat.2018.07.057. Epub 2018 Jul 23.
Azadirachtin, a tetranortriterpenoid botanical insecticide, has varied sub-lethal effects against many insect pests, including antifeedant, repellent, and growth regulatory. Despite extensive studies of the mechanisms that underline these physiological effects, little attention has been given to multiple toxic effects of azadirachtin under a coherent concentration, and there is no definitive overarching consensus on its toxicity. Here, we investigated multiple sub-lethal effects induced by 4 mg L of azadirachtin, which did not elicit antifeedant behavior in Drosophila melanogaster, on metrics of longevity, development, compound eyes and reproduction. Exposure to <20 mg L azadirachtin did not induce mortality, and 4 mg L of azadirachtin could shorten lifespan, expression of detoxification genes and activities of related detoxification enzymes were higher. The lower activity of chitinase and higher content of chitin in fruit fly exposed to 4 mg L azadirachtin could be important in developmental inhibition effects, and ovarian abnormalities and lower fecundity could have resulted from azadirachtin-mediated influences on juvenile hormone and ecdysone that disrupted the endocrine system. Caspase-3, head involution defective and reaper-dependent apoptosis genes may have been responsible for compound eye abnormalities in flies exposed to azadirachtin. Our findings provide important insights to the potential mechanisms of sub-lethal effects of azadirachtin.
印楝素，一种四环三萜植物源杀虫剂，对许多昆虫害虫具有不同的亚致死效应，包括拒食、驱避和生长调节。尽管对这些生理效应的机制进行了广泛的研究，但对印楝素在一致浓度下的多种毒性作用关注甚少，其毒性也没有明确的总体共识。在这里，我们研究了在不引起黑腹果蝇拒食行为的情况下，4mg/L 印楝素引起的多种亚致死效应，包括寿命、发育、复眼和繁殖的衡量标准。暴露于<20mg/L 的印楝素不会引起死亡，而 4mg/L 的印楝素可以缩短寿命，解毒基因的表达和相关解毒酶的活性更高。在接触 4mg/L 印楝素的果蝇中，几丁质酶活性较低，几丁质含量较高，这可能是发育抑制作用的重要原因，而卵巢异常和生育能力降低可能是由于印楝素对保幼激素和蜕皮激素的影响，破坏了内分泌系统。caspase-3、头退化缺陷和 reaper 依赖的凋亡基因可能是接触印楝素的果蝇复眼异常的原因。我们的研究结果为印楝素的亚致死效应的潜在机制提供了重要的见解。
