环丙沙星对斑马鱼早期发育阶段的神经毒性研究

Neurotoxicity of Ciprofloxacin on Early Life Stages of Danio rerio

环丙沙星是恩诺沙星的主要代谢产物,因其抗菌谱广、杀菌力强、起效快等优点而被广泛应用,在土壤、水体等环境中被不同程度检出,然而目前有关环丙沙星对鱼类早期生命发育阶段的神经毒性效应研究较少。采用模式动物斑马鱼(Danio rerio)作为研究对象,在0.1、1 mg·L^(-1)浓度水平上,从胚胎自发运动、运动活性、乙酰胆碱酶活性及多巴胺、血清素通路和神经发育关键基因的表达等方面评估环丙沙星对斑马鱼早期发育阶段的神经毒性。结果表明,0.1 mg·L^(-1)浓度组抑制斑马鱼胚胎自发运动(P<0.001),1 mg·L^(-1)浓度组诱导乙酰胆碱酯酶活性(P<0.05);1 mg·L^(-1)浓度组斑马鱼运动行为活跃(P<0.05)和光照刺激惊恐反应性增加(P<0.01);同时,胆碱能系统、多巴胺、血清素通路和神经发育系统的ache、shha、th2、htr1aa、htr5a表达上调(P<0.05),gfap、dat、nestin基因表达下调(P<0.05)。这些结果表明环丙沙星可能通过影响多巴胺、血清素和神经发育关键基因的表达产生神经毒性,进而影响运动行为。

Ciprofloxacin is the main metabolite of enrofloxacin,which is widely used because of its broad antibacterial spectrum,strong bactericidal force and rapid onset of action,and has been detected in soil,water and other environments to varying degrees.However,there are few studies on the neurotoxic effects of ciprofloxacin on early life stages of fish development.Therefore,in this study,the model animal zebrafish(Danio rerio)was used to assess the neurotoxicity of ciprofloxacin on zebrafish at early developmental stages in terms of embryonic spontaneous movements,motor activity,acetylcholinesterase activity and expression of dopamine and serotonin pathways and key neurodevelopmental genes at concentrations of 0.1 mg·L^(-1) and 1 mg·L^(-1).Our results showed that the 0.1 mg·L^(-1) concentration group inhibited the spontaneous movement of zebrafish embryos(P<0.001),and the 1 mg·L^(-1) concentration group induced acetylcholinesterase activity(P<0.05).Zebrafish in 1 mg·L^(-1) group showed active locomotor activity(P<0.05)and increased startle response upon light stimulation(P<0.01);at the same time,upregulation of the expression levels of genes ache,shha,th2,htr1aa and htr5a(P<0.05),and downregulation of the expression levels of genes gfap,dat and nestin(P<0.05)were observed,which regulate the cholinergic,dopaminergic,serotoninergic and neurodevelopmental systems.These results suggested that ciprofloxacin produced neurotoxicity by affecting the expression of dopamine,serotonin and key neurodevelopmental genes,thereby causing alterations in motor behavior.