Diabetic
wound is a chronic
wound in which normal process of wound healing is interrupted. Lack of blood supply,
infection and lack of functional
growth factors are assumed as some of the conditions that lead to non-healing environment.
Epidermal growth factor (
EGF) acts primarily to stimulate epithelial cell growth across
wound.
Erythropoietin (EPO) is a haematopoietic factor, which stimulates the production, differentiation and maturation of erythroid precursor cells. This study hypothesised combining these two factors, non-healing process of diabetic
wound will be compensated and eventually lead to acceleration of wound healing compared with single
growth factor treatment. A total of 30 diabetic Sprague-Dawley rats were divided into three treatment groups (single treatment of rh-EPO or rh-
EGF or combined treatment on a full-thickness skin
wound). To assess the wound healing effects of the components, the
wound size and the healing time were measured in each treatment groups. The skin histology was examined by light microscopy and immunohistochemical analysis of proliferating markers was performed. The combined treatment with rh-EPO and rh-
EGF improved full-thickness
wound significantly (P < 0·05) accelerating 50% healing time with higher expression of Ki-67 compared with single
growth factor-treated groups. The combined treatment failed to accelerate the total healing time when compared with single
growth factor treatments. However, the significant improvement were found in
wound size reduction in the combined treatment group on day 4 against single
growth factor-treated groups (P < 0·05). This study demonstrated that the combined treatment of rh-EPO and rh-
EGF improved the wound healing possibly through a synergistic action of each
growth factor. This application provides further insight into combined
growth factor therapy on non-healing diabetic
wounds.