Roxadustat promotes angiogenesis through HIF-1α/VEGF/VEGFR2 signaling and accelerates cutaneous wound healing in diabetic rats

Diabetic foot ulcers are a major health-care burden worldwide. One primary cause of the delayed wound healing in diabetic patients is impaired function of the hypoxia-inducible factor-1 alpha/vascular endothelial growth factor (HIF-1 alpha/VEGF) axis, which results in compromised neovascularization in response to hypoxia. In the present study, we aimed to investigate the effect of roxadustat, a novel HIF prolyl-4-hydroxylase inhibitor, on angiogenesis and its therapeutic effect on cutaneous wound healing in diabetic rats. In vitro, we found that roxadustat could promote the angiogenic activity of human umbilical vein endothelial cells, accompanied by up-regulation of HIF-1 alpha/VEGF/VEGFR2 signaling. Next, we demonstrated that Ki8751, a VEGFR2-specific inhibitor, could inhibit the increased angiogenic activity of human umbilical vein endothelial cells induced by roxadustat. In vivo, we performed a Matrigel plug assay and demonstrated that roxadustat induced vascularization of the Matrigel plugs, and this effect could be partially inhibited by Ki8751. Finally, we utilized a streptozotocin-induced diabetic rat model and found that roxadustat could accelerate cutaneous wound healing and promote angiogenesis in the wound sites. In conclusion, roxadustat promotes angiogenesis via activation of the HIF-1 alpha/VEGF/VEGFR2 pathway and exhibits therapeutic effects on diabetic wound healing by increasing angiogenesis. Our findings suggest that roxadustat can be a promising strategy to promote diabetic cutaneous wound healing.