Unité de Recherche RiverLy Ecotoxicology Laboratory, INRAE, 5, Rue de La Doua C.S. 20244, 69625, Villeurbanne Cedex, France.
Université du Québec À Montréal (UQAM), Département Des Sciences Biologiques, 141, Avenue du Président-Kennedy, C.P. 8888, Succursale Centre-Ville, Montréal, Québec, H3C 3P8, Canada.
Environ Sci Pollut Res Int. 2023 Aug;30(36):86060-86071. doi: 10.1007/s11356-023-28327-w. Epub 2023 Jul 3.
In the last decade, the freshwater amphipod Gammarus fossarum proved to be a promising sentinel species in active biomonitoring programs to assess the effects of environmental contamination on non-target organisms. Given that the highly conserved retinoid (RETs) metabolism supports many biological functions and is perturbed by xenobiotics and used as biomarker for vertebrates, we explored the RETs functions in the crustacean model Gammarus fossarum. More specifically, we studied the implication of all -trans retinoic acid (atRA) in the reproduction (embryo, oocyte, and juvenile production) and development (success and delay of molting) by exposing G. fossarum females to atRA and citral (CIT), a known inhibitor of RA synthesis. In parallel, we exposed gammarids to methoprene (MET) and glyphosate (GLY), two pesticides suspected to interfere with atRA metabolism and signaling and frequently found in water systems. After 14 days of exposure, atRA, CIT, and MET reduced the number of oocytes, whereas only MET caused a reduced number of embryos. After 44 days, MET and GLY showed a tendency to decrease juvenile production. The duration of the molting cycle increased following the exposures to atRA and MET, while the treatment with CIT caused a typical endocrine disruptive inverted U-shaped curve. The exposure to GLY led to increased duration of the molting cycle at the lowest concentrations and lowered molting success at the highest concentration tested. This study highlights for the first time the implication of RA in the oogenesis and molting of G. fossarum and suggests that it may be a potential mediator of MET-induced effects on these processes. This study adds to the comprehension of the reproductive and developmental control in G. fossarum and opens new research avenues to study the effects of xenobiotics on the RET system in this sentinel species. Ultimately, our study will drive the development of RET-based biomarkers for non-target aquatic invertebrates exposed to xenobiotics.
在过去的十年中，淡水端足目动物食蚊鱼已被证明是主动生物监测计划中一种很有前途的指示物种，可用于评估环境污染对非目标生物的影响。鉴于高度保守的类视黄醇（RETs）代谢支持许多生物学功能，并且受到外源性化学物质的干扰，可作为脊椎动物的生物标志物，我们探索了甲壳动物模型食蚊鱼中的 RETs 功能。更具体地说，我们研究了全反式视黄酸（atRA）在生殖（胚胎、卵母细胞和幼体产生）和发育（蜕皮的成功和延迟）中的作用，方法是使食蚊鱼雌性接触 atRA 和柠檬醛（CIT），CIT 是一种已知的 RA 合成抑制剂。同时，我们使食蚊鱼接触到 methoprene（MET）和草甘膦（GLY），这两种农药都被怀疑会干扰 atRA 代谢和信号传导，并且经常在水系中发现。暴露 14 天后，atRA、CIT 和 MET 减少了卵母细胞的数量，而只有 MET 导致胚胎数量减少。44 天后，MET 和 GLY 表现出降低幼体产生的趋势。atRA 和 MET 的暴露增加了蜕皮周期的持续时间，而 CIT 的处理导致典型的内分泌干扰倒 U 形曲线。暴露于 GLY 导致在最低浓度时蜕皮周期持续时间增加，而在最高浓度时蜕皮成功率降低。这项研究首次强调了 RA 在食蚊鱼卵母细胞发生和蜕皮中的作用，并表明它可能是 MET 对这些过程产生影响的潜在介质。这项研究增加了对食蚊鱼生殖和发育控制的理解，并为研究 Xenobiotics 对该指示物种 RET 系统的影响开辟了新的研究途径。最终，我们的研究将推动基于 RET 的生物标志物的开发，用于研究 Xenobiotics 对暴露于 Xenobiotics 的非目标水生无脊椎动物的影响。
