Di-(2-ethylhexyl) phthalate impairs angiogenesis and hematopoiesis via suppressing VEGF signaling in zebrafish

Abstract

Di-(2-ethylhexyl) phthalate (DEHP) is among the most widely used plasticizers in plastic production, which has been detected in various environments. However, DEHP safety remains poorly known. Using zebrafish models, the effects of DEHP on the angiogenesis and hematopoiesis, and the underlying mechanism, were studied. Transgenic zebrafish embryos with specific fluorescence of vascular endothelial cells, myeloid cells, or hematopoietic stem cells were exposed to 0, 100, 150, 200, or 250 nM of DEHP for 22, 46 or 70 h, followed by fluorescence observation, endogenous alkaline phosphatase activity measurement, erythrocyte staining, and gene expression analysis by quantitative PCR and whole mount in situ hybridization. High DEHP concentrations decreased the sprouting rate, average diameter, and length, and the expansion area of the vessels lowered the EAP activity and suppressed the vascular endothelial growth factor (vegf) and hematopoietic marker genes, including c-myb, hbae1, hbbe1, and lyz expressions. DEHP treatment also decreased the number of hematopoietic stem cells, erythrocytes, and myeloid cells at 24 and 72 hpf. These DEHP-induced angiogenetic and hematopoietic defects might be alleviated by vegf overexpression. Our results reveal a plausible mechanistic link between DEHP exposure-induced embryonic angiogenetic defect and hematopoietic impairment.