Abstract:
Dibutyl phthalate (DBP) is a widely-used plasticizer that is dispersed in various environments, causing significant pollution and health risks. The toxic mechanism of DBP has been discussed in recent years, while the susceptibility of mitochondrial DNA (mtDNA) to DBP exposure and the resulting damage remain unclear. In this study, maternal zebrafish were exposed to environmentally relevant concentration of DBP for 0, 2, 4, and 6 weeks. Results showed that DBP exposure impaired health status, leading to the reduced body length and weight, condition factor, hepatosomatic index, and gonadosomatic index. Furthermore, DBP exposure induced oxidative stress and ATP deficiency in the gill and liver in a time-dependent manner. The oxidized mtDNA (ox-mtDNA) levels in the D-loop and ND1 regions were assessed in different tissues, showing distinct response patterns. The high energy-consuming tissues such as heart, brain, gill, and liver exhibited elevated susceptibility to mitochondrial damage, with a rapid increase in ox-mtDNA levels in the short term. Conversely, in muscle, ovary, eggs, and offspring, ox-mtDNA gradually accumulated over the exposure period. Notably, the ox-mtDNA levels in the D-loop region of blood showed a prompt response to DBP exposure, making it convenient for evaluation. Additionally, decreased hatching rates, increased mortality, lipoperoxidation, and depressed swimming performance were observed in offspring following maternal DBP exposure, suggesting the inherited impairments of maternal mtDNA. These findings highlight the potential for ox-mtDNA to serve as a convenient biomarker for environmental contamination, aiding in ecological risk assessment and forewarning systems in aquatic environment.
摘要:
邻苯二甲酸二丁酯(DBP)是一种广泛使用的增塑剂,分散在各种环境中,造成严重的污染和健康风险。近年来对DBP的毒性机制进行了探讨,而线粒体DNA(mtDNA)对DBP暴露的敏感性以及由此产生的损伤仍不清楚。在这项研究中,母本斑马鱼暴露于环境相关浓度的DBP中0、2、4和6周.结果显示,DBP暴露损害健康状况,导致身长和体重减少,条件因子,肝细胞指数,和性腺指数。此外,DBP暴露以时间依赖性方式诱导了g和肝脏中的氧化应激和ATP缺乏。在不同组织中评估了D环和ND1区域的氧化mtDNA(ox-mtDNA)水平,显示不同的反应模式。高耗能组织如心脏,大脑,吉尔,肝脏对线粒体损伤的易感性升高,在短期内,ox-mtDNA水平迅速增加。相反,在肌肉中,子房,鸡蛋,和后代,ox-mtDNA在暴露期间逐渐积累。值得注意的是,血液D-loop区域的ox-mtDNA水平显示出对DBP暴露的迅速反应,便于评价。此外,孵化率下降,死亡率增加,脂过氧化,母亲DBP暴露后,后代游泳表现不佳,提示母体mtDNA的遗传性损伤。这些发现强调了ox-mtDNA作为环境污染的方便生物标志物的潜力,协助水生环境的生态风险评估和预警系统。