School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, China.
Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
Chem Res Toxicol. 2021 Apr 19;34(4):1114-1123. doi: 10.1021/acs.chemrestox.0c00518. Epub 2021 Mar 19.
Methylmercury (MeHg) is a common organic form of mercury in water, which has been linked to several forms of biological toxicity. However, studies on the ecotoxicity risk of long-term exposure to low-dose MeHg are insufficient for the assessment of environmental safety. In the present study, the effects of MeHg on multiple generations (P0-F3) and population of were investigated under long-term, low-dose exposure. We investigated the multigenerational toxicity of MeHg by analyzing reproductive and developmental indicators. According to our results, exposure to 100 nM MeHg had little effect on the parental generation (P0) but caused serious reproductive toxicity in the offspring (F1-F3), and the effect of MeHg was aggravated with each passing generation. The genes related to apoptosis and DNA damage were upregulated in the F3 generation. Pearson correlation analysis showed that the changes in these genes were closely related to the apoptosis of gonadal cells. Furthermore, chronic exposure to MeHg (from 100 to 1000 nM group) caused a sharp decline in population size and triggered the "bag of worms" phenotype. Genes related to vulvar development were downregulated in the F3 generation after treatment with 100 nM MeHg. These data suggest that long-term low-dose MeHg exposure adversely affected and its offspring and triggered multigenerational toxicity and population discrepancy.
甲基汞（MeHg）是水中常见的汞有机形态，已被证明与多种生物毒性有关。然而，关于长期低剂量 MeHg 暴露的生态毒性风险的研究还不足以进行环境安全性评估。在本研究中，通过分析繁殖和发育指标，研究了长期低剂量 MeHg 暴露对 多个世代（P0-F3）和种群的影响。我们通过分析生殖和发育指标来研究 MeHg 的多代毒性。根据我们的结果，暴露于 100 nM MeHg 对亲代（P0）几乎没有影响，但对后代（F1-F3）造成严重的生殖毒性，且 MeHg 的影响随着每一代的传递而加剧。与细胞凋亡和 DNA 损伤相关的基因在 F3 代中上调。Pearson 相关分析表明，这些基因的变化与性腺细胞凋亡密切相关。此外，慢性暴露于 MeHg（从 100 nM 到 1000 nM 组）导致种群数量急剧下降，并引发“恶性循环”表型。在 100 nM MeHg 处理后，F3 代中与外阴发育相关的基因下调。这些数据表明，长期低剂量 MeHg 暴露对 和其后代产生了不良影响，并引发了多代毒性和种群差异。
