Modulation of alpha4 integrin mRNA levels is coupled to deficits in vasomotor function in rat arterioles by allylamine

Quercetin protects endothelial function from inflammation induced by localized disturbed flow by inhibiting NRP2 -VEGFC complex

Atherosclerosis is a focal chronic inflammatory disease, the initial pathogenic event of which is endothelial dysfunction, and disturbed flow (DF) is the primary and vital factor underlying endothelial dysfunction. The present research aims to elucidate the mechanism underlying the regulation of Neuropilin (NRP)2 under DF in endothelial cells (ECs) in an inflammatory state. We observed that NRP2 expression was significantly upregulated in DF-stimulated human umbilical vein endothelial cells (HUVECs). Knockdown of NRP2 in HUVECs significantly ameliorated cell inflammation induced by DF. In addition, quercetin inhibited NRP2 expression as well as endothelial inflammation. Animal experiments suggested that NRP2 knockdown or intraperitoneal injection of quercetin affected the expression of inflammation-related genes. Moreover, the upstream transcription factor GATA2 was found to regulate NRP2 transcription by binding to the -1100 to +100 bp region of the NRP2 promoter. Further studies showed that quercetin inhibited NRP2-VEGFC complex formation induced by disturbed flow, although did not inhibit GATA2 expression. These findings suggest that NRP2 plays an important role in promoting inflammation. Quercetin antagonizes atherosclerosis by inhibiting NRP2 and the formation of NRP2-VEGFC complex by inhibiting the inflammatory effects induced by disordered flow.

NRP2 promotes atherosclerosis by upregulating PARP1 expression and enhancing low shear stress-induced endothelial cell apoptosis

Atherosclerosis-related cardiovascular diseases are leading causes of mortality worldwide, characterized by the development of endothelial cell dysfunction, increased oxidized low-density lipoprotein uptake by macrophages, and the ensuing formation of atherosclerotic plaque. Local blood flow patterns cause uneven atherosclerotic lesion distribution, and endothelial dysfunction caused by disturbed flow is an early step in the development of atherosclerosis. The present research aims to elucidate the mechanism underlying the regulation of Neuropilin 2 (NRP2) under low shear stress (LSS) in the atheroprone phenotype of endothelial cells. We observed that NRP2 expression was significantly upregulated in LSS-stimulated human umbilical vein endothelial cells (HUVECs) and in mouse aortic endothelial cells. Knockdown of NRP2 in HUVECs significantly ameliorated cell apoptosis induced by LSS. Conversely, overexpression of NRP2 had the opposite effect on HUVEC apoptosis. Animal experiments suggest that NRP2 knockdown markedly mitigated the development of atherosclerosis in Apoe^-/- mice. Mechanistically, NRP2 knockdown and overexpression regulated PARP1 protein expression in the condition of LSS, which in turn affected the expression of apoptosis-related genes. Moreover, the upstream transcription factor GATA2 was found to regulate NRP2 expression in the progression of atherosclerosis. These findings suggest that NRP2 plays an essential proatherosclerotic role through the regulation of cell apoptosis, and the results reveal that NRP2 is a promising therapeutic target for the treatment of atherosclerotic disorders.