Exposure To Prothioconazole Induces Developmental Toxicity And Cardiovascular Effects On Zebrafish Embryo

Prothioconazole is a fungicide that has been widely used in agriculture and livestock husbandry.However,over-using may pose potential risks to both the environment and human health.In early 2019,some prothioconazole-based products were registered in China.Since prothioconazole is widely used in rice fields,it is very important to evaluate its effect on aquatic organisms.In this study,zebrafish was chosen for test according to OECD test.LC50(96h)of prothioconazole on embryos,larvae and adults were 1.705,2.170 and 3.600 mg/L respectively.Prothioconazole was middle toxicity to zebrafish.Effects of prothioconazole on the embryonic development of zebrafish.The results showed that exposure to 0.22,0.43 and 0.85 mg/L increased mortality and hatching rate.Morphologic abnormalities showed up,including heart and yolk-sac edema,spine curvature,tail deformity,shortened body length and decreased eye area.Pericardial edema was the most common characterization,so the next study discussed cardiovascular effects of zebrafish.Studies have shown that exposure to prothioconazole can lead to a decrease in heart rate and the number of red blood cell.The expression of atp2a1l,atp2a2a and tbx5 dropped significantly in the high concentration group,we guess calcium signaling pathway may be the main molecular mechanism of inhibition of cardiac function.Prothioconazole can also change the structure of heart,causing pericardial edema,SV-BA distance increased,and apoptosis surround the cardiac region.After exposure,the heart showed string and thin.the SV-BA distance confirmed the serious malformations.Apoptosis around pericardial region was observed by AO staining.The expression of vmhc and amhc declined,showed that prothioconazole can influence the expression of cardiac myosin,lower gata4 destroys the late cardiac cyclic movement.We also found that the expression of myl7,bmp2b and nkx2.5 decreased.The expression of hand2 expression increased,maybe it's a response to injury.The expression of flil decreased significantly,indicating that prothioconazole could inhibit the vascular development in zebrafish.