Department of Analytical and Applied Chemistry, School of Engineering, Institut Químic de Sarrià-Universitat Ramon Llull, 08017 Barcelona, Spain.
Institute for Environmental Assessment and Water Research (IDAEA-CSIC), 08034 Barcelona, Spain.
Ecotoxicol Environ Saf. 2024 Jan 15;270:115888. doi: 10.1016/j.ecoenv.2023.115888. Epub 2023 Dec 26.
Glyphosate, a globally prevalent herbicide known for its selective inhibition of the shikimate pathway in plants, is now implicated in physiological effects on humans and animals, probably due to its impacts in their gut microbiomes which possess the shikimate pathway. In this study, we investigate the effects of environmentally relevant concentrations of glyphosate on the gut microbiota, neurotransmitter levels, and anxiety in zebrafish. Our findings demonstrate that glyphosate exposure leads to dysbiosis in the zebrafish gut, alterations in central and peripheral serotonin levels, increased dopamine levels in the brain, and notable changes in anxiety and social behavior. While the dysbiosis can be attributed to glyphosate's antimicrobial properties, the observed effects on neurotransmitter levels leading to the reported induction of oxidative stress in the brain indicate a novel and significant mode of action for glyphosate, namely the impairment of the microbiome-gut-axis. While further investigations are necessary to determine the relevance of this mechanism in humans, our findings shed light on the potential explanation for the contradictory reports on the safety of glyphosate for consumers.
草甘膦，一种全球普遍存在的除草剂，因其对植物中芳香族氨基酸生物合成途径的选择性抑制作用而闻名，现在与人类和动物的生理效应有关，可能是由于它对具有芳香族氨基酸生物合成途径的肠道微生物组的影响。在这项研究中，我们调查了环境相关浓度的草甘膦对斑马鱼肠道微生物组、神经递质水平和焦虑的影响。我们的研究结果表明，草甘膦暴露导致斑马鱼肠道菌群失调，中枢和外周 5-羟色胺水平改变，大脑中多巴胺水平升高，焦虑和社交行为发生显著变化。虽然肠道菌群失调可以归因于草甘膦的抗菌特性，但观察到的神经递质水平的变化导致大脑中氧化应激的报道表明，草甘膦具有一种新的、重要的作用模式，即损害微生物组-肠道轴。虽然需要进一步的研究来确定这一机制在人类中的相关性，但我们的研究结果为草甘膦对消费者安全性的矛盾报告提供了潜在的解释。
