Citrus-derived auraptene stimulates angiogenesis by activating the Erk- and PI3K/Akt/eNOS-dependent signaling pathways in human umbilical vein endothelial cells

Auraptene is a citrus-derived natural monoterpene that has been shown to exert anticancer, anti-bacterial, anti-inflammatory, and antioxidant roles. Since little is known about other biological functions of auraptene, we examined the efficacy of auraptene for stimulating angiogenesis in human umbilical vein endothelial cells (HUVECs). Treatment with low concentrations of auraptene stimulated endothelial cell proliferation, migration, and tube formation. Furthermore, auraptene activated Erk, Akt, and endothelial nitric oxide synthase (eNOS), and increased NO production. Auraptene also partially induced the phosphorylation of VEGFR2. Furthermore, auraptene-induced activation of Erk, Akt, and eNOS were significantly inhibited by the inhibitors PD98059, LY294002, and L-NIO dihydrochloride. These results suggest that auraptene stimulates angiogenesis by regulating the VEGFR2, Erk, and PI3K/Akt-eNOS signaling pathways. (C) 2012 Elsevier Ltd. All rights reserved.