Embryonic exposure to prothioconazole induces oxidative stress and apoptosis in zebrafish (Danio rerio) early life stage

Triazole fungicides are extensively applied in general agriculture for fungal control and have negative impacts on aquatic organisms. Prothioconazole, a widely used triazole fungicide, is toxic to zebrafish, but systematic research on the negative effects caused by prothioconazole in zebrafish embryos is limited. In this study, we studied the developmental toxicology, oxidative stress and apoptosis caused by prothioconazole in zebrafish embryos. Exposure to 0.850 mg/L prothioconazole impacts embryo survival and hatching. Prothioconazole exposure caused embryo malformation, especially yolk-sac and pericardial edemas, and prothioconazole-induced apoptosis was observed. Additionally, exposure to a high prothioconazole concentration up-regulated the expression levels of oxidative stress defense-related genes and p53. The bax to bcl2 ratio increased along with exposure time and prothioconazole concentration. Prothioconazole induced apoptosis during the early life stages of zebrafish and may trigger oxidative-stress and p53-dependent pathway responses. Our findings increase our understanding of the molecular mechanisms of oxidative stress and cell death caused by prothioconazole.