Liang Ximei, Wang Lan, Ou Ruikang, Nie Xiangping, Yang YuFeng, Wang Fang, Li Kaibin
Department of Ecology, Jinan University, Guangzhou, 510632, China.
Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, China.
Ecotoxicology. 2015 Oct;24(7-8):1566-73. doi: 10.1007/s10646-015-1457-1. Epub 2015 Apr 19.
The presence of antibiotics including norfloxacin in the aquatic environment may cause adverse effects in non-target organisms. But the toxic mechanisms of fluoroquinolone to fish species are still not completely elucidated. Thus, it is essential to investigate the response of fish to the exposure of fluoroquinolone at molecular or cellular level for better and earlier prediction of these environmental pollutants toxicity. The sub-chronic toxic effects of norfloxacin (NOR) on swordtail fish (Xiphophoru s helleri) were investigated by measuring mRNA expression of cytochrome P450 1A (CYP1A), cytochrome P450 3A (CYP3A), glutathione S-transferase (GST) and P-glycoprotein (P-gp) and their corresponding enzyme activities (including ethoxyresorufin O-deethylase, erythromycin N-demethylase and GST. Results showed that NOR significantly affected the expression of CYP1A, CYP3A, GST and P-gp genes in swordtails. The gene expressions were more responsive to NOR exposure than their corresponding enzyme activities. Moreover, sexual differences were found in gene expression and enzyme activities of swordtails exposed to NOR. Females displayed more dramatic changes than males. The study further demonstrated that the combined biochemical and molecular parameters were considered as useful biomarkers to improve our understanding of potential ecotoxicological risks of NOR exposure to aquatic organisms.
水生环境中包括诺氟沙星在内的抗生素的存在可能会对非目标生物产生不利影响。但是氟喹诺酮对鱼类的毒性机制仍未完全阐明。因此，有必要在分子或细胞水平上研究鱼类对氟喹诺酮暴露的反应，以便更好、更早地预测这些环境污染物的毒性。通过测量细胞色素P450 1A（CYP1A）、细胞色素P450 3A（CYP3A）、谷胱甘肽S-转移酶（GST）和P-糖蛋白（P-gp）的mRNA表达及其相应的酶活性（包括乙氧基异吩恶唑酮O-脱乙基酶、红霉素N-脱甲基酶和GST），研究了诺氟沙星（NOR）对剑尾鱼（Xiphophorus helleri）的亚慢性毒性作用。结果表明，NOR显著影响剑尾鱼中CYP1A、CYP3A、GST和P-gp基因的表达。基因表达对NOR暴露的反应比其相应的酶活性更敏感。此外，在暴露于NOR的剑尾鱼的基因表达和酶活性中发现了性别差异。雌性比雄性表现出更显著地变化。该研究进一步证明，综合生化和分子参数可作为有用的生物标志物，以增进我们对NOR暴露于水生生物的潜在生态毒理学风险的理解。
