Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada.
Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada.
Sci Total Environ. 2021 Jan 1;750:141633. doi: 10.1016/j.scitotenv.2020.141633. Epub 2020 Aug 16.
Bisphenol S (BPS) is increasingly used in a wide range of industrial and consumer products, resulting in its ubiquitous distribution across the environment, including aquatic ecosystems. Although it is commonly known as a weak/moderate estrogenic compound, there has been a growing acknowledgment of the potential of BPS to cause toxicity by inducing oxidative stress. Oxidative stress is a major participant in the development of anxiety-like behaviors in humans and animals. Therefore, the present study was designed to examine the impact of BPS on anxiety-like behavior and fear responses in adult zebrafish and also to elucidate the possible linkage between the BPS neurotoxicity and oxidative status of the brain. To this end, adult male and female zebrafish were exposed to 0 (control), 1, 10, and 30 μg/L of BPS and 1 μg/L of 17-β-estradiol (E2) for 75 days. Following exposure, changes in anxiety and fear-related responses were evaluated by applying a novel tank test and by exposing focal fish to chemical alarm cues. Additionally, we evaluated the expression of multiple antioxidant genes in the zebrafish brain. Our results indicate that BPS, irrespective of exposure concentration, and E2 significantly decreased bottom-dwelling behavior and the latency to enter the upper water column. Furthermore, exposure to the highest concentration of BPS and E2 induced a significant decrease in fear-related responses. The impaired anxiety and reduced fear-related responses were associated with a down-regulation in the transcription of genes involved in enzymatic antioxidant defense. Taken together, our results suggest that chronic exposure to BPS impairs anxiety and fear responses in adult zebrafish, possibly by inducing oxidative stress in the brain.
双酚 S（BPS）被广泛应用于各种工业和消费产品中，导致其在环境中无处不在，包括水生生态系统。尽管它通常被认为是一种弱/中度雌激素化合物，但越来越多的人认识到 BPS 有可能通过诱导氧化应激而产生毒性。氧化应激是导致人类和动物出现焦虑样行为的主要因素之一。因此，本研究旨在研究 BPS 对成年斑马鱼焦虑样行为和恐惧反应的影响，并阐明 BPS 神经毒性与大脑氧化状态之间的可能联系。为此，雄性和雌性成年斑马鱼分别暴露于 0（对照）、1、10 和 30μg/L 的 BPS 和 1μg/L 的 17-β-雌二醇（E2）中 75 天。暴露后，通过应用新的鱼缸测试和将焦点鱼暴露于化学警报线索来评估焦虑和恐惧相关反应的变化。此外，我们还评估了斑马鱼大脑中多种抗氧化基因的表达。我们的结果表明，BPS 无论暴露浓度如何，以及 E2 均显著降低了底部栖息行为和进入上水区的潜伏期。此外，暴露于最高浓度的 BPS 和 E2 会导致与恐惧相关的反应显著下降。焦虑受损和恐惧相关反应减少与参与酶抗氧化防御的基因转录下调有关。总之，我们的研究结果表明，慢性暴露于 BPS 会损害成年斑马鱼的焦虑和恐惧反应，这可能是通过在大脑中诱导氧化应激所致。
