Puerarin Improves Dexamethasone-Impaired Wound Healing In Vitro and In Vivo by Enhancing Keratinocyte Proliferation and Migration

The delayed and impaired wound healing caused by dexamethasone (DEX) is commonly reported. Puerarin, the major isoflavone found in Pueraria montana var. lobata (Willd.) Sanjappa & Pradeep promoted the wound healing process in diabetic rats. However, the effects and underlying mechanisms of puerarin on DEX-impaired wound healing have not been investigated. This study examined the potential uses of puerarin in upregulating keratinocyte proliferation and migration in dexamethasone (DEX)-suppressed wound healing model. The effects of puerarin on wound healing in vivo were investigated by taking full-thickness 5 mm punch biopsies from the dorsal skin of BALB/c mice and then treating them topically with 0.1% DEX. For the in vitro study, DEX-treated HaCaT cells were used to examine the effects of puerarin on DEX-induced keratinocyte proliferation and migration and the mechanisms of its action. Puerarin, when applied topically, accelerated the wound closure rate, increased the density of the capillaries, and upregulated the level of collagen fibers and TGF-β in the wound sites compared to the DEX-treated mice. Puerarin promoted the proliferation and migration of keratinocytes by activating the ERK and Akt signaling pathways in DEX-treated HaCaT cells. In conclusion, puerarin could be effective in reversing delayed and disrupted wound healing associated with DEX treatments.