Topical administration of Juglans regia L. leaf extract accelerates diabetic wound healing

BACKGROUND: Diabetic wounds are one of the most important issues in diabetic patients. It seems that Juglans regia L. leaf with antioxidant and anti-inflammatory potentials can be profitable for healing of diabetic wounds. The aim of present study was to investigate the topical administration of Juglans regia L. leaf extract in diabetic wound healing. METHODS: Seventy-five diabetic male rats were randomly divided into 5 groups (n = 15), including: untreated (Control) group, Eucerin group, 2% Juglans regia L. ointment (JRL 2%) group, 5% Juglans regia L. ointment (JRL 5%) group, and Phenytoin group as a reference drug. Sampling was performed at days 7, 14, and 21 after surgery. Evaluation tests included stereology, immunohistochemistry, molecular, and biomechanical. RESULTS: Our results showed that the wound closure rate, volumes of newly formed of epidermis and dermis, density of fibroblasts and blood vessels, collagen deposition, density of proliferation cells, expression levels of TGF-β and VEGF genes, and biomechanical characteristics were significantly higher in extract groups compared to control and eucerin groups, however, these changes were considerable in the JRL 5% group (P < 0.05). This is while that the density of neutrophils and expression levels of TNF-α and IL-1β genes in the extract groups, especially in the JRL 5% group, were significantly reduced compared to control and eucerin groups (P < 0.05). CONCLUSION: Topical administration of Juglans regia L. leaf extract, especially in 5% concentration, considerably accelerates diabetic wound healing. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12906-022-03735-6.