College of Animal Science & Technology, Jiangxi Agricultural University, Nanchang, 330045, PR China.
College of Chemistry & Environmental Science, Guangdong Ocean University, Zhanjiang, 524088, PR China.
Chemosphere. 2023 Dec;344:140315. doi: 10.1016/j.chemosphere.2023.140315. Epub 2023 Sep 26.
It has been reported that antibiotic enrofloxacin can impair reproductive function of mammals, induces multi-generational oscillatory effects on reproduction of Caenorhabditis elegans, and disturbes endocrine system in grass carp.
This study aims to explore the effect of short-term enrofloxacin exposure on sex steroid hormones biosynthesis in Carassius auratus var. Pengze through assessing the contents of growth hormone (GH), thyroid hormone 4 (T), estradiol (E) and testosterone (T) in plasma, and investigating sex steroid hormones biosynthesis based on targeted metabonomics analysis, and determining expression level of some important genes, gonadotropin-releasing hormone (gnrh), gonadotropin hormone 1-β (gth1-β), gonadotropin hormone 2-β (gth2-β) and cyp19a1a in hypothalamus-pituitary-ovary axis (HPOA).
We found that short-term exposure of enrofloxacin disordered contents of E and T in plasma of fish determined by ELISA detection, T content elevation and E content decline, which was confirmed by the following data from targeted metabonomics analysis of plasma. The metabonomic results showed that both T and its upstream intermediate products during the process of sex steroid hormones biosynthesis in fish were increased significantly, but E content was decreased markedly. At the exposure 24 h of enrofloxacin, expression of gnrh in hypothalamus, gth1-β and gth2-β in pituitary were promoted. Meanwhile GH and T contents in plasma, two inducers of sex steroid hormones synthesis, were augmented, which indicated that sex steroid hormones biosynthesis was improved. However cyp19a1a expression in ovary was repressed, and content of estriol (E) was upregulated. These data suggested that enrofloxacin promoted sex steroid hormones biosynthesis and conversion of E to estriol (E), but inhibited the conversion of T to E. Finally, content of E was declined sharply.
Animal specific antibacterial enrofloxacin is widely detectable in aquatic ecosystem, exposure of the agent can induce adverse effects on plants and animals. This study firstly evidenced induction of disruption of sex steroid hormones by enrofloxacin in fish, which indicates enrofloxacin is an endocrine disruption compound that can induce endocrine disruption of animals, including fish.
已有报道称抗生素恩诺沙星会损害哺乳动物的生殖功能，对秀丽隐杆线虫的生殖产生多代振荡效应，并扰乱草鱼的内分泌系统。
本研究旨在通过检测血浆中生长激素（GH）、甲状腺激素 4（T）、雌二醇（E）和睾酮（T）的含量，探讨短期恩诺沙星暴露对彭泽鲫性类固醇激素生物合成的影响，基于靶向代谢组学分析研究性类固醇激素生物合成，并确定下丘脑-垂体-性腺轴（HPOA）中一些重要基因促性腺激素释放激素（gnrh）、促性腺激素 1-β（gth1-β）、促性腺激素 2-β（gth2-β）和 cyp19a1a 的表达水平。
我们发现，通过 ELISA 检测，短期暴露于恩诺沙星会扰乱鱼血浆中 E 和 T 的含量，表现为 T 含量升高和 E 含量下降，这一结果得到了血浆靶向代谢组学分析数据的进一步证实。代谢组学结果表明，鱼体内性类固醇激素生物合成过程中 T 及其上游中间产物均显著增加，而 E 含量明显下降。在恩诺沙星暴露 24 h 时，下丘脑 gnrh、垂体 gth1-β 和 gth2-β 的表达均得到促进。同时，血浆中 GH 和 T 含量这两种性类固醇激素合成的诱导剂也增加，表明性类固醇激素生物合成得到了改善。然而，卵巢中的 cyp19a1a 表达受到抑制，雌三醇（E）含量上调。这些数据表明，恩诺沙星促进了性类固醇激素的生物合成和 E 向雌三醇（E）的转化，但抑制了 T 向 E 的转化。最终，E 的含量急剧下降。
动物专用抗菌药物恩诺沙星在水生生态系统中广泛存在，该药物的暴露会对植物和动物产生不良影响。本研究首次证明恩诺沙星可诱导鱼类性类固醇激素紊乱，表明恩诺沙星是一种内分泌干扰化合物，可诱导包括鱼类在内的动物内分泌紊乱。
