Ruyi Jinhuang Powder accelerated diabetic ulcer wound healing by regulating Wnt/β-catenin signaling pathway of fibroblasts In Vivo and In Vitro

Diabetic ulcer is a common complication of diabetes. Therapies of diabetic ulcer are still challenging due to the complicated aetiology. Ruyi Jinhuang Powder (RJP) is gradually adopted to treat diabetic ulcer and has a significant therapeutic effect.To investigate the therapeutic potential for diabetic ulcer in vivo and in vitro, we explored whether and how RJP influences wound healing in mice and fibroblasts at the tissular, cellular and molecular levels.The chemical composition of RJP was identified by HPLC. Streptozotocin (STZ) induced diabetic mice were used to confirm the curative effect of RJP in vivo. Besides, the impact of RJP in stimulating fibroblasts proliferation, migration and reducing inflammation was studied through CCK-8 assay, cell scratch assay, PCR, WB, etc. RESULTS: A total of 17 compounds were identified in RJP by HPLC. Our data indicated that RJP promoted fibroblasts proliferation and migration via activating Wnt/β-catenin signaling pathway. Consistently, RNA-seq analysis of mice skin samples also showed that the shared differentially expressed genes (DEGs) between RJP group and control group were most enriched in wnt signaling pathway. These DEGs were closely related with wound repair. In addition, the anti-inflammation effect of RJP was also confirmed through downregulation of IL-1α, IL-1β, IL-6 and IL-10 expression levels. These biological effects were reduced when the Wnt/β-catenin signaling was blocked. The in vivo study also demonstrated the effect of RJP in improving epidermal wound closure, which was consistent with the in vitro results.Topical application of RJP was effective in treating diabetic ulcer. This research is helpful to provide new insights and evidence into the role of RJP in accelerating unhealing wound and reducing wound inflammation.