Diethylhexyl phthalate exposure promotes mitophagy through Drp1-mediated mitochondrial fission in neural crest cells of chick embryos

Di(2-ethylhexyl) phthalate (DEHP) has been used commonly in industrial production and has endocrine disrupting ability. DEHP has potential adverse effects on the development of fetal programming, but the toxic effects and mechanism study in neural crest cells is not enough understood. To investigate DEHP's effects on neural tube closure injury, the chicken embryos and primary cranial neural crest (CNC) cells model of DEHP-treatment was established. Here, we show that the development of neural tube is disrupted by DEHP, which causes an observed decrease in levels of HNK1 and Pax7 and increase in levels of adhesion molecules and extracellular matrix. This led to inhibit the migration and epithelial-mesenchymal transition (EMT) mechanism in neural crest cells, which cause dysraphism in chicken embryos. Furthermore, DEHP exposure also disrupts mitochondrial function accompanied by the elevation of Drp1 and FIS1 level, and the decrease of MFN1, MFN2, and OPA1 level, causing excessive mitochondrial fragmentation, mitophagy and apoptosis, eventually decreasing the MMP levels and ATP concentration in chicken embryos. Conversely, the addition of Drp1 inhibitor dramatically alleviate the mitochondrial fragmentation and mitophagy induced by DEHP in primary CNC cells. Our results reveal the mechanism of DEHP-induced mitophagy in neural crest cells was regulated by excessive activation of Drp1-mediated mitochondrial fission. These findings deepen the research of reproductive toxicology of DEHP and guide its application in different areas, especially in the agricultural field.