Li Jitong, Wang Yinghuan, Li Wei, Xu Peng, Guo Baoyuan, Li Jianzhong, Wang Huili
Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing 100049, China.
Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China.
Ecotoxicol Environ Saf. 2017 Aug;142:284-292. doi: 10.1016/j.ecoenv.2017.04.035. Epub 2017 Apr 28.
Triadimefon (TF, S-(+)-TF, R-(-)-TF) and its metabolite triadimenol (TN, TN-A1, A2 and TN-B1, B2) are two systemic fungicides and both of them are chiral pharmaceuticals which are widely used in agricultural industry. Many researches focused on the toxicity effects of triadimefon on mammals, while the ecotoxicological data of tiradimefon on reptiles is limited. In order to understand the toxicity mechanism of triadimefon in reptiles, the current study administrated S-(+)-TF or R-(-)-TF traidimefon (50mg/kg) to Chinese lizards (Eremias argus) respectively, the absorption, distribution of triadimefon and the formation of triadimenol were analysed at different sampling times. The metabolic pathways were demonstrated through relative gene expression using quantitative real-time PCR reaction. During the experiment time, triadimefon was quickly peaked to the maximum concentration within 12h in liver, brain, kidney, and plasma, eliminated slowly. The biotransformation in kidney was the lowest and fat possessed the worst degradation ability among others. The metabolite, triadimenol was detected in blood in 2h and reached to a plateau at about 12h in most organs (fat excepted), while the process of metabolism is stereoselective. The mainly metabolite in R-(-)-TF treated group was TN-B1, and TN-A2 in S-(+)-TF group which showed the selective metabolism to other species caused by environmental conditions, differences in the animal models and concentration of TF. The related gene expression of cyp1a1, cyp3a1 and hsd11β mRNA level in lizards showed different metabolic pathways in the liver and brain. Both P450s enzymes and 11β-hydroxysteroid dehydrogenase participated in metabolic reaction in liver, while no 11β-hydroxysteroid dehydrogenase pathway observed in brain. This diversity in liver and brain may cause different degradation rate and ecotoxicological effect in different organs.
三唑酮（TF，S-(+)-TF，R-(-)-TF）及其代谢产物三唑醇（TN，TN-A1、A2以及TN-B1、B2）是两种内吸性杀菌剂，它们均为手性药物，在农业中广泛应用。许多研究聚焦于三唑酮对哺乳动物的毒性作用，而关于三唑酮对爬行动物的生态毒理学数据有限。为了解三唑酮在爬行动物中的毒性机制，本研究分别给中国石龙子（丽斑麻蜥）施用S-(+)-TF或R-(-)-TF三唑酮（50mg/kg），并在不同采样时间分析三唑酮的吸收、分布以及三唑醇的形成。通过定量实时PCR反应，利用相对基因表达来证明代谢途径。在实验期间，三唑酮在肝脏、脑、肾脏和血浆中于12小时内迅速达到最高浓度，随后缓慢消除。肾脏中的生物转化最低，脂肪的降解能力在其他组织中最差。代谢产物三唑醇在2小时内在血液中被检测到，在大多数器官（脂肪除外）中约12小时达到平台期，而代谢过程具有立体选择性。R-(-)-TF处理组中的主要代谢产物是TN-B1，S-(+)-TF组中的主要代谢产物是TN-A2，这表明环境条件、动物模型差异以及三唑酮浓度导致了对其他物种的选择性代谢。石龙子中cyp1a1、cyp3a1和hsd11β mRNA水平的相关基因表达在肝脏和脑中显示出不同的代谢途径。P450s酶和11β-羟基类固醇脱氢酶均参与肝脏中的代谢反应，而在脑中未观察到11β-羟基类固醇脱氢酶途径。肝脏和脑的这种差异可能导致不同器官中不同的降解速率和生态毒理学效应。
