双酚AP对斑马鱼心脏发育毒性作用研究

Effect of Bisphenol AP on the Developing Heart of Zebrafish

双酚AP(BPAP)是一种环境内分泌干扰物,在环境及人体中均有所分布。之前的研究阐述了双酚类似物BPAF对斑马鱼发育和心脏环化的影响及其潜在机制,但BPAP对心脏发育的毒性作用及其作用机制尚未阐明。该课题将斑马鱼胚胎暴露于不同浓度的BPAP,利用荧光显微技术与荧光定量PCR等方法,对染毒后96 h内的斑马鱼胚胎和幼鱼的孵化、心脏发育形态、心脏发育相关的4个心脏转录因子(Gata4、Hand2、Nkx2.5、Tbx5)的表达以及心肌细胞活性氧水平等4个方面进行研究,旨在研究BPAP对斑马鱼心脏发育毒性。实验结果表明,BPAP引起斑马鱼胚胎孵化率下降、死亡率升高、心率降低以及心脏环化障碍等,且与BPAP的剂量相关。深入研究表明,BPAP能诱导斑马鱼胚胎以及幼鱼心肌细胞氧化应激以及下调心脏发育有关的转录因子Gata4、Hand2、Nkx2.5、Tbx5。由此可知,BPAP影响斑马鱼胚胎发育和心脏环化障碍,通过诱导心肌细胞的氧化应激和下调心脏发育相关的转录因子。

Bisphenol AP(BPAP) is an endocrine-disrupting chemical, distributing in both environment and human body.Our previous studies demonstrated the effect of BPAF on the heart development of zebrafish and its underlying mechanism. However, the effect of BPAP on the developing heart still remains to be investigated. The zebrafish embryos at 24 hours post fertilization(hpfs) were exposed to different concentrations of BPAP. Then we examined the hatching rate of embryos, the morphology changes of developing heart, the expression of four cardiogenic transcription factors and the ROS level using quantitative PCR and fluorescence microscopy during a period of 96 hours after the exposure. The results showed that BPAP caused decreased hatching rate and heart rate, as well as increased mortality rate and heart looping disorder in zebrafish embryos, indicating a dose-dependent correlation. Further studies indicated that BPAP could induce cardiomyocyte oxidative stress and downregulate the expression of cardiogenic transcription factors including Nkx2.5, Gata4,Tbx5 and Hand2 in zebrafish larvas. These results suggest that BPAP can affect zebrafish embryonic development, especially heart looping by inducing ROS-dependent oxidative stress and downregulating the expression of cardiogenic transcription factors.