Topical application of Hydroxysafflor Yellow A accelerates the wound healing in streptozotocin induced T1DM rats

To investigate the effects of Hydroxysafflor Yellow A (HSYA), which is derived from safflower, on the proliferation, migration and angiogenesis of cells in vitro and its potential efficacy in vivo when topically applied to a diabetic wound. Human umbilical vein endothelial cells (HUVECs) and mouse macrophage cells (RAW264.7) were used to evaluate angiogenesis and anti-inflammatory activities, respectively. The influence of HSYA on the wound scratch assay was investigated in keratinocytes. A splinted excisional wound model in rats with TIDM induced by streptozotocin was used to assess the effects of wound healing. Collagen disposition and secretion of vascular growth factors (VEGF) as well as transforming growth factor-beta 1 (TGF-beta 1) were evaluated by an ELISA assay and histological staining. The in vitro results showed that HSYA could significantly enhance both the neovascularization of HUVECs and the migration of keratinocytes. It showed the significant inhibitory effect on nitric oxide production, indicating the anti-inflammatory activity of HSYA. In vivo, the topical application of HSYA significantly enhanced the wound closure rate, and the time to complete wound closure was 17 days, whereas 30 days were needed with PBS treatment. Further, treatment with HSYA exhibited significant granulation tissue formation with higher collagen content, re-epithelialization and angiogenesis according to Masson's trichrome staining evaluation, VEGE and TGF-beta 1 ELISA measurement. In conclusion, HSYA application could be considered a promising therapeutic strategy for treating chronic non-healing diabetic foot ulcers.