Effects of Okadaic Acid on Zebrafish (Danio rerio) Behavior and Cellular Pathways: Insights from Transcriptome Analysis

This study investigates the toxicological effects of okadaic acid (OA), a marine biotoxin, on zebrafish behavior and cellular mechanisms in C2C12 cells. Zebrafish exposed to varying OA concentrations exhibited concentration-dependent behavioral changes, including increased bottom-dwelling and reduced locomotion, indicative of neurotoxic effects. At the cellular level, OA exposure in C2C12 cells resulted in elevated oxidative stress markers, such as reactive oxygen species (ROS) and malondialdehyde (MDA). Transcriptomic analysis revealed significant activation of the p53 pathway, characterized by upregulation of pro-apoptotic genes (puma and bax) and downregulation of the anti-apoptotic gene BCL-2, driving mitochondrial apoptosis. The observed oxidative stress and p53-mediated apoptosis provide a mechanistic link between OA-induced cellular toxicity and behavioral alterations in zebrafish. These findings underscore the dual impact of OA on organismal behavior and cellular health, offering valuable insights into its mechanisms of action. Moreover, the study highlights zebrafish behavior as a sensitive bioindicator for OA exposure, demonstrating its potential utility in environmental biomonitoring programs. Overall, this research enhances understanding of OA's ecological risks, providing critical data to support marine environmental safety and public health protection.