Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America.
Boz Life Science Research and Teaching Institute, San Diego, California, United States of America.
PLoS One. 2021 Apr 6;16(4):e0249432. doi: 10.1371/journal.pone.0249432. eCollection 2021.
Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread natural and anthropogenic pollutants, and some PAHs are proven developmental toxicants. We chemically characterized clean and heavily polluted sites and exposed fish embryos to PAH polluted sediment extracts during four critical developmental stages. Embryos were collected from Fundulus heteroclitus populations inhabiting the clean and heavily polluted Superfund estuary. Embryos of parents from the clean sites are sensitive to PAH pollutants while those of parents from the heavily polluted site are resistant. Chemical analysis of embryos suggests PAH accumulation and pollution-induced toxicity among sensitive embryos during development that ultimately kills all sensitive embryos before hatching, while remarkably, the resistant embryos develop normally. The adverse effects on sensitive embryos are manifested as developmental delays, reduced heart rates, and severe heart, liver, and kidney morphological abnormalities. Gene expression analysis of early somitogenesis, heartbeat initiation, late organogenesis, and pre-hatching developmental stages reveals genes whose expression significantly differs between sensitive and resistant embryo populations and helps to explain mechanisms of sensitivity and resistance to polluted environments during vertebrate animal development.
多环芳烃（PAHs）是最广泛存在的天然和人为污染物之一，其中一些多环芳烃已被证明是发育毒物。我们对清洁和重度污染的地点进行了化学特征描述，并在四个关键发育阶段将鱼类胚胎暴露于多环芳烃污染的沉积物提取物中。胚胎取自栖息在清洁和重度污染超级基金河口的弗拉基米尔异齿鳉种群。来自清洁地点的父母的胚胎对多环芳烃污染物敏感，而来自重度污染地点的父母的胚胎则具有抗性。胚胎的化学分析表明，在发育过程中，敏感胚胎会积累多环芳烃并产生污染诱导的毒性，最终导致所有敏感胚胎在孵化前死亡，而令人惊讶的是，抗性胚胎则正常发育。对敏感胚胎的不利影响表现为发育延迟、心率降低以及严重的心脏、肝脏和肾脏形态异常。对早期体节形成、心跳启动、晚期器官发生和孵化前发育阶段的基因表达分析揭示了敏感和抗性胚胎群体之间表达显著不同的基因，有助于解释脊椎动物发育过程中对污染环境的敏感性和抗性的机制。
