Paraquat affects the differentiation of neural stem cells and impairs the function of vascular endothelial cells: a study of molecular mechanism

Abstract

To investigate the effect of paraquat (PQ) exposure on gene expression in neural stem cells as well as structures and functions of vascular endothelial cells. RNA-Seq was used to explore the differentially expressed genes in human umbilical cord blood-neural stem cells (HUCB-NSCs) at different stages (eg, proliferation, early and late differentiation) in the presence of PQ. The effects of PQ on human umbilical vein endothelial cells (HUVECs), including cell proliferation, apoptosis, cytokines secretion, and expression of tight junction proteins, were assessed with CCK-8, flow cytometry, ELISA, and western blot analysis, individually. A total of 53 genes were up-regulated and 61 genes were down-regulated in PQ treated HUCB-NSCs, including seven genes associated with the differentiation of neural stem cells, for example, Gfap, S100B, Oct4, Gdf3, Sox1, Pax6, and Ngn1. PQ treatment significantly reduced the proliferation of HUVECs, inhibited cytokines secretion (VEGF, BFGF) and expressions of tight junction-associated protein (Claudin 1, Occludin, ZO-1), as well as induced significant apoptosis. Our study suggests that PQ impairs the development of nervous system by regulating the expression of genes associated with neural stem cell differentiation, as well as the structure and function of vascular endothelial cells, which together lead to abnormality in the nervous system.