Effects of spinetoram on the developmental toxicity and immunotoxicity of zebrafish

Abstract

Our study investigated the effects of spinetoram on the developmental toxicity and immunotoxicity of zebrafish. 10 h post-fertilization (hpf) zebrafish embryos were exposed to several concentrations of spinetoram (0, 5.0 mg/L, 7.5 mg/L, 10 mg/L) for up to 96 hpf, and their mortality, heart rate, number of innate and adaptive immune cells, oxidative stress, apoptosis and gene expression were detected. Studies indicated that the spinetoram exposed zebrafish embryos showed yolk sac edema, slow growth, decreased heart rate, decreased number of immune cells, delayed thymic development and cell apoptosis. In addition, there were also significant changes in oxidative stress related indicators in zebrafish, the content of ROS and MDA and the activity of CAT and SOD increased with the increase of spinetoram concentration. Moreover, we detected the expression of TLR4 related genes including TLR4, MYD88 and NF-κB p65 which were significantly up-regulated in the treated groups. Meanwhile, we also found that pro-inflammatory factors IL-6, IL-8, IFN-γ and CXCL-c1c were up-regulated, but anti-inflammatory factor IL-10 was down-regulated in the treated groups. Briefly, our results show that spinetoram induces the developmental toxicity and immunotoxicity of zebrafish to a certain extent, providing basis for the further research on the molecular mechanism of spinetoram exposure to aquatic ecosystems.