Total Flavones of Abelmoschus manihot Exhibits Pro-Angiogenic Activity by Activating the VEGF-A/VEGFR2-PI3K/Akt Signaling Axis

Angiogenesis is a process of new blood vessel formation from pre-existing vessels. Vascular endothelial growth factor-A (VEGF-A) binds to VEGF receptor-2 (VEGFR2) and thus activation of phosphatidylinositol 3-kinase (PI3K)/Akt pathway play a central role in angiogenesis. Total flavones of Abelmoschus manihot (TFA), the major active component of the traditional Chinese herb Abelmoschus manihot, display novel pro-angiogenic activity. However, little information concerning its underlying mechanism is available. Here we investigate the pro-angiogenesis of TFA with the aim of understanding its mechanism of action. Human umbilical vein endothelial cells (HUVECs) and the chick chorioallantoic membrane (CAM) model were used to evaluate pro-angiogenesis of TFA using cell viability, wounding healing, transwell invasion, tube formation, RT-qPCR and Western blot methods. LY294002, a PI3K inhibitor, was used to interfere with PI3K/Akt pathway signal for assessing the underlying mechanism. Results in vitro indicated TF...