Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Shuangqing RD 18 , Beijing 100085 , China.
University of Chinese Academy of Sciences , Yuquan RD 19 a , Beijing 100049 , China.
J Agric Food Chem. 2018 Nov 7;66(44):11640-11646. doi: 10.1021/acs.jafc.8b03713. Epub 2018 Oct 29.
The metabolic process of diflubenzuron in rat or fish has been well studied, but little is known about its elimination pathway in lizard. The current study predicted the metabolic route of diflubenzuron in lizard feces and compared the toxicity of diflubenzuron and 4-chloroaniline on lizard thyroid system. The amido bond cleavage was the major route for diflubenzuron elimination in lizard feces. 4-Chloroaniline as the most toxic diflubenzuron metabolite was also abundant in feces. According to liver slices, 4-chloroaniline exposure induced significant changes of nuclear shape, while diflubenzuron exposure caused significant hepatocytes clustering. On the basis of thyroid hormone and thyroid-related gene levels, triiodothyronine (T3) level in lizard liver was regulated by thyroid hormone receptors, while thyroxine (T4) concentration was modulated by dio2 and udp genes after diflubenzuron or 4-chloroaniline exposure. These results showed that both diflubenzuron and 4-chloroaniline could disrupt lizard thyroid system, which could provide evidence for lizard population decline.
在大鼠或鱼类中，已对除虫脲的代谢过程进行了深入研究，但对其在蜥蜴中的消除途径知之甚少。本研究预测了除虫脲在蜥蜴粪便中的代谢途径，并比较了除虫脲和 4-氯苯胺对蜥蜴甲状腺系统的毒性。酰胺键断裂是除虫脲在蜥蜴粪便中消除的主要途径。4-氯苯胺作为毒性最大的除虫脲代谢物，在粪便中也很丰富。根据肝切片，4-氯苯胺暴露会导致核形状发生明显变化，而除虫脲暴露会导致肝细胞聚集。根据甲状腺激素和甲状腺相关基因水平，甲状腺激素受体调节蜥蜴肝脏中的三碘甲状腺原氨酸 (T3) 水平，而二碘氧嘧啶 (Dio2) 和尿苷二磷酸 (UDP) 基因在暴露于除虫脲或 4-氯苯胺后调节甲状腺素 (T4) 浓度。这些结果表明，除虫脲和 4-氯苯胺均可破坏蜥蜴的甲状腺系统，这可为蜥蜴种群减少提供证据。
