Introduction: The lifetime incidence of foot ulcers has been estimated to be 19% to 34% among persons with diabetes. Diabetic wound healing(DWH) remains a challenge. Given the promising role of stem cells in wound healing, the current study proposed to improve DWH by mobilizing and recruiting bone marrow stem cells pharmacologically with combination of AMD3100 and low-dose FK506 (AF) in rats.
Methods: T2 GK rats and STZ induced T1DM SD rats were used. To determine the role of bone marrow stem cells, bone marrow from GFP tg Lewis were transplanted into wt Lewis rats and T1 rats were induced by STZ injection at 2 months following bone marrow transplantation. Full-thickness wounds were created in the dorsal skin or in the foot skin at 6 weeks after STZ injection or GK rats at 4 month old. Wounded rats were divided into two experimental groups and received saline or a combination of AMD3100 (1mg/kg) and FK506 (0.1mg/kg) immediately after wounding and every 2 days until complete healing.
Results: At the time of wounding, all animals developed peripheral artery disease and neuropathy. The back wound healing time was reduced from 27 to 19 days and the foot wound healing time was reduced from 25 to 20 days in T1DM rats treated with AF. Similarly, the back wound healing time was reduced from 26(S) to 21(AF) days in GK rats. Equally important, healing was accompanied by reduced scar and regeneration of hair follicles. Searching for the mechanisms, we found that AF therapy mobilized bone marrow stem cells to peripheral blood and recruited bone marrow-derived CD31+CD133+ endothelial progenitor cells, CD34+ stem cells and Ym1/2+ M2 macrophages into the wound sites and enhanced capillary and hair follicle neogenesis.
Conclusion: Combination of AMD3100 and low-dose FK506 results in better and faster healing of diabetic wounds in rats with diabetic peripheral artery disease and neuropathy. Our findings offer a significant therapeutic approach to healing of DFU.
L. Qi: None. A.R. Ahmadi: None. J. Huang: None. Q. Lin: None. M. Chen: None. H. Kuwabara: None. K. Iwasaki: None. J. Burdick: None. Z. Sun: None.