Pilose antler extract promotes angiogenesis and vascular maturation to accelerate wound healing.

Angiogenesis plays a crucial role in early wound healing by providing essential nutrients and oxygen to tissue cells, supporting the growth of epithelial cells and other tissue cells. The essence of angiogenesis lies in the proliferation and migration of endothelial cells. Pilose antler extract (PAE) accelerates early-stage wound healing. Proteomic analysis shows its role in vascular tension regulation, cell migration, and angiogenesis. This study aims to investigate the effects and pharmacological mechanisms of PAE on angiogenesis and vascular maturation during the early stages of wound healing. We used a full-thickness skin excision model in rats, utilizing endothelial cell analysis to examine PAE's regulatory mechanisms on angiogenesis. In situ hybridization combined with CD31 immunofluorescence was performed to localize Vegfa mRNA within vascular regions, verifying endothelial-specific upregulation in vivo. In vitro, PI3K inhibitors (LY294002 and Wortmannin) and an AKT inhibitor (MK-2206) were employed to confirm the pathway specificity of PAE-induced angiogenic effects. PAE accelerates the formation of vascular networks and the restoration of blood flow perfusion in early wound healing. In addition, it promotes the proliferation, migration and formation of endothelial cell tubular structures by activating the PI3K-AKT signaling pathway, upregulating the level of VEGFR2 and p-AKT1 in endothelial cells. The co-localization of Vegfa mRNA and CD31⁺ vessels confirmed that PAE specifically enhances VEGFA expression within vascular endothelium in vivo. Furthermore, PAE dynamically regulates the expression of Ang-1, Ang-2, and Tek, demonstrating its time-dependent regulatory effects on angiogenesis and remodeling during wound healing. The positive effects of PAE on wound healing and recovery of blood flow are counteracted when LY294002 inhibits PI3K activity. Pharmacological inhibition with LY294002, Wortmannin, or MK-2206 significantly reversed PAE-induced endothelial proliferation, migration, and tube formation, confirming that the PI3K-AKT axis is essential for PAE's pro-angiogenic activity. Local treatment with PAE can increase the expression level of VEGFR2 and activate the PI3K-AKT signaling pathway to promote angiogenesis and accelerate wound healing, while dynamically regulating the expression of Ang-1, Ang-2, and Tek, accelerating vascular maturation, and promoting the formation of functional vessels during wound healing. These findings, supported by endothelial co-localization and inhibitor validation experiments, provide direct mechanistic evidence that PAE promotes angiogenesis through PI3K-AKT pathway activation. Our study first revealed that PAE promotes angiogenesis by activating the PI3K-AKT pathway. Additionally, we dynamically monitored PAE's time-dependent regulation of angiogenesis and remodeling, highlighting its crucial role in maintaining their balance.