The effect of midkine on growth factors and oxidative status in an experimental wound model in diabetic and healthy rats

Wound healing is important for longevity. Midkine is a cytokine involved in controlling tissue repair and new tissue development, and in regulating inflammation. We investigated the effect of midkine on wound healing in rats. In total, 108 Wistar albino rats were used: 12 as healthy and diabetic controls; 96 were split into 4 groups: healthy, saline treated; healthy, midkine (10 ng/kg, 48 h intervals) treated; diabetic, saline treated; and diabetic, midkine treated. Following wound creation, 6 rats per group were euthanized on days 3, 7, 14, and 28; the wounded skin was removed. Levels of epidermal growth factor (EGF), matrix metalloproteinase-8 (MMP-8), transforming growth factor beta (TGF-β), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and thiobarbituric acid reactive substances (TBARS) were measured. MMP-8 and PDGF levels fluctuated in all groups; TGF-β fluctuated in the diabetic groups and was significantly higher in the HM group than other groups after 14 days. EGF and VEGF levels were increased in the HM group after 3 days. TBARS levels were highest in the diabetic groups. Macroscopically, the midkine-treated groups healed better. Midkine can accelerate wound healing by influencing growth factors and oxidative status in wound tissues.