FG-4592 combined with PRP significantly accelerates the healing of refractory diabetic wounds by upregulating HIF-1α

Chronic refractory wounds are a common, costly and recurrent complication of diabetes. Platelet-rich plasma (PRP), a new therapy for chronic wounds, is limited by a long treatment period and unstable effects. FG-4592(Roxadustat) is a new prolyl-4-hydroxylation domain(PHD) inhibitor, which can stabilize hypoxia-inducible factor-1α(HIF-1α) effectively. It is a promising drug for wound repair and needs to be demonstrated via various appropriate application scenarios. This study investigated the effects of combining FG-4592 and PRP to promote diabetic wound healing. Diabetic rats were randomly assigned to five groups: nondiabetic control, diabetic untreated, diabetic + PRP, diabetic + FG-4592, and diabetic + PRP + FG-4592. Diabetes was induced with streptozotocin (STZ). A full-thickness skin defect was created, and FG-4592 (peritoneal injection) and PRP (periwound injection) were administered alone or together. Wound healing was assessed by histological analysis (Hematoxylin-Eosin (HE) and Masson staining) and protein expression of HIF-1α, VEGF(vascular endothelial growth factor), α-SMA(α-smooth muscle actin), CoL1α1(collagen type 1 alpha 1), and SDF-1(Stromal Cell-derived Factor 1) via Western blotting and qRT-PCR(Quantitative real time polymerase chain reaction). Immunohistochemistry(IHC) and immunofluorescence(IF) were also used to evaluate CD34 (Cluster of Differentiation 34), CD31(Cluster of Differentiation 31), VEGF(vascular endothelial growth factor), SDF-1(Stromal Cell-derived Factor 1), PCNA(Proliferating Cell Nuclear Antigen), and Integrin-β1 expression. The untreated diabetic group exhibited impaired wound healing, histological damage, and reduced expression of key proteins compared to the nondiabetic control group. Both PRP and FG-4592 alone improved wound healing, reduced damage, and upregulated protein expression. However, the combination of FG-4592 and PRP showed the most significant improvement. This study suggests that FG-4592 combined with PRP accelerates diabetic wound healing by enhancing endothelial progenitor cell recruitment, neovascularization, and cell proliferation and migration via upregulation of HIF-1α and its target genes. This combination therapy may provide a novel approach for treating chronic diabetic wounds.