Department of Chemistry, North Carolina A&T State University, Greensboro, NC, USA.
Division of Natural Sciences, New College of Florida, 5800 Bay Shore Road, Sarasota, FL 34243, USA.
Mol Omics. 2022 Aug 15;18(7):635-642. doi: 10.1039/d2mo00046f.
Glyphosate is among the world's most commonly used herbicides in agriculture and weed control. The use of this agrochemical has unintended consequences on non-target organisms, such as honey bees (), the Earth's most prominent insect pollinator. However, detailed understanding of the biological effects in bees in response to sub-lethal glyphosate exposure is still limited. In this study, H NMR-based metabolomics was performed to investigate whether oral exposure to an environmentally realistic concentration (7.12 mg L) of glyphosate affects the regulation of honey bee metabolites in 2, 5, and 10 days. On Day 2 of glyphosate exposure, the honey bees showed significant downregulation of several essential amino acids, including leucine, lysine, valine, and isoleucine. This phenomenon indicates that glyphosate causes an obvious metabolic perturbation when the honey bees are subjected to the initial caging process. The mid-term (Day 5) results showed negligible metabolite-level perturbation, which indicated the low glyphosate impact on active honeybees. However, the long-term (Day 10) data showed evident separation between the control and experimental groups in the principal component analysis (PCA). This separation is the result of the combinatorial changes of essential amino acids such as threonine, histidine, and methionine, while the non-essential amino acids glutamine and proline as well as the carbohydrate sucrose were all downregulated. In summary, our study demonstrates that although no significant behavioral differences were observed in honey bees under sub-lethal doses of glyphosate, metabolomic level perturbation can be observed under short-term exposure when met with other environmental stressors or long-term exposure.
草甘膦是农业和杂草控制中世界上使用最广泛的除草剂之一。这种农用化学品对非靶标生物（如蜜蜂（Apis mellifera），地球上最突出的昆虫传粉媒介）有意外的后果。然而，对于蜜蜂在亚致死剂量草甘膦暴露下的生物学效应的详细了解仍然有限。在这项研究中，采用基于 1H NMR 的代谢组学方法研究了口服暴露于环境现实浓度（7.12mg/L）的草甘膦是否会影响 2、5 和 10 天的蜜蜂代谢物的调节。在草甘膦暴露的第 2 天，蜜蜂表现出几种必需氨基酸（包括亮氨酸、赖氨酸、缬氨酸和异亮氨酸）的显著下调。这一现象表明，当蜜蜂经历初始笼养过程时，草甘膦会导致明显的代谢扰动。中期（第 5 天）结果显示代谢物水平的微小扰动，表明活性蜜蜂受到的草甘膦影响较低。然而，长期（第 10 天）的数据表明，在主成分分析（PCA）中，对照组和实验组之间有明显的分离。这种分离是由于必需氨基酸（如苏氨酸、组氨酸和蛋氨酸）的组合变化引起的，而非必需氨基酸（如谷氨酰胺和脯氨酸）以及碳水化合物蔗糖都被下调。总之，我们的研究表明，尽管在亚致死剂量的草甘膦下，蜜蜂没有观察到明显的行为差异，但在短期暴露于其他环境胁迫或长期暴露时，代谢组水平的扰动是可以观察到的。
