School of Agriculture and Food Science, Zhejiang A& F University, Lin'an, HangZhou 311300, China.
Institute of Pesticides and Environmental Toxicology, Zhejiang University, HangZhou 310058, China.
Ecotoxicol Environ Saf. 2018 Nov 30;164:149-154. doi: 10.1016/j.ecoenv.2018.08.020. Epub 2018 Aug 11.
As a new tetronic acid derivative insecticide, spirotetramat has been reported to be toxic to an array of aquatic organisms. However, the toxic effects of spirotetramat on zebrafish especially at ovary are still obscure. Hereby, the acute toxicity of spirotetramat towards zebrafish（Danio rerio），as well as the changes on biochemical and histological traits of ovary were investigated. The acute toxicity test results showed that the median lethal concentration (LC) value of spirotetramat were 9.61 mg/L and 7.21 mg/L at 72 h and 96 h, respectively, suggesting spirotetramat has moderate toxicity to zebrafish. In the following sub-lethal toxicity test, the gene expression of superoxide dismutase (SOD), catalase (CAT), and gonadotropic hormone receptor (FSHR and LHR) together with the content of malondialdehyde (MDA) in ovary were measured at 14, 21, and 28 days after exposure to 36, 360 and 720 μg/L. Under high concentration treatment (360 and 720 μg/L), MDA content, the relative transcription CAT and SOD gene level increased significantly in ovary (p < 0.05). That indicated sub-lethal doses spirotetramat caused oxidative stress and lipid peroxidation in zebrafish ovary during the entire experimental period. Under the exposure to spirotetramat at 720 μg/L after 14 days, the relative transcript FSHR gene level was down regulated, and the relative transcript LHR gene level was up regulated. Moreover, spirotetramat affected the oocyte development especially on the diameter size and maturation during the ovary tissue biopsies at 28 days. Taken together, these findings revealed the adverse effects of spirotetramat on fish from the biochemical and histological aspects.
作为一种新型四氢呋喃酸衍生物杀虫剂，螺虫乙酯已被报道对多种水生生物具有毒性。然而，螺虫乙酯对斑马鱼（Danio rerio），尤其是对卵巢的毒性作用仍不清楚。本研究旨在调查螺虫乙酯对斑马鱼的急性毒性以及对卵巢生化和组织学特征的影响。急性毒性试验结果表明，螺虫乙酯在 72 h 和 96 h 时的半数致死浓度（LC）值分别为 9.61 mg/L 和 7.21 mg/L，表明螺虫乙酯对斑马鱼具有中等毒性。在随后的亚致死毒性试验中，在暴露于 36、360 和 720 μg/L 后 14、21 和 28 天，测量了卵巢中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和促性腺激素受体（FSHR 和 LHR）的基因表达以及丙二醛（MDA）的含量。在高浓度处理（360 和 720 μg/L）下，卵巢中 MDA 含量、相对转录 CAT 和 SOD 基因水平显著增加（p<0.05）。这表明，亚致死剂量的螺虫乙酯在整个实验期间导致了斑马鱼卵巢中的氧化应激和脂质过氧化。在暴露于 720 μg/L 螺虫乙酯 14 天后，FSHR 基因的相对转录水平下调，LHR 基因的相对转录水平上调。此外，螺虫乙酯在 28 天的卵巢组织活检中影响卵母细胞的发育，特别是卵母细胞的直径大小和成熟。总之，这些发现从生化和组织学方面揭示了螺虫乙酯对鱼类的不良影响。
