Enantioselective Toxicity of Ethiprole to Honeybees ( Apis mellifera ) via Varying Interference of Cytochrome P450s in Metabolism

Limited understanding of the enantioselective toxicity mechanism of chiral pesticides hinders honeybee protection. S-Ethiprole posed high toxicity to honeybees, yet its mechanism remains unknown. We investigated the enantioselective mechanisms of rac-, R-, and S-ethiprole on honeybees following 7 day exposure at 15 μg/L, using metabolomics, enzymatic assays, qPCR, molecular docking, and molecular dynamics simulations (MD). The results indicated that rac-, R-, and S-ethiprole induced differential perturbations of honeybee metabolism. Notably, S-ethiprole significantly downregulated CYP450 genes expression, decreased CYP450 content, and impaired the metabolism of xenobiotics by CYP450 to a greater extent than rac- and R-ethiprole. Consistently, molecular docking showed that S-ethiprole exhibited broader but weaker affinity for sensor proteins in detoxification-related transcriptional regulatory pathways than R-ethiprole. Moreover, MD suggested that the specific binding of S-ethiprole to Keap1 may inhibit activation of the CncC/Keap1 pathway. Our research provided valuable insights into guiding ethiprole use strategies to protect honeybee health.