Does Obesity without Hyperglycemia Delay Wound Healing in an Obese Mouse Model Induced by a High-Fat Diet?

It was unclear that wound healing was delayed in obesity without hyperglycemia. The purpose of this study was to compare the wound healing process between obese and non-obese mice without hyperglycemia by attaching a splint. Three-week-old male mice (C57BL/6N) were fed high-fat diets (60% of calories from fat) in the obesity group, and commercial diets in the control group for 15 weeks. Two circular (4 mm in diameter) full-thickness wounds were made on the dorsal skin. Body weights and serum leptin levels were significantly higher in the obesity group than in the control group until day 15 after wounding. Fasting blood glucose levels before wounding were lower in the obesity group than in a hyperglycemic rodent model. The macrophage infiltration into subcutaneous fat before wounding in the obesity group was negligible. The ratios of the wound area were not significantly different between the two groups. No significant differences were observed in the number of neutrophils or macrophages or new blood vessels and ratio of myofibroblasts or collagen fibers between the two groups. Our results demonstrated that cutaneous wound healing was not delayed in the obesity group without hyperglycemia and macrophage infiltration into the subcutaneous fat and with high serum leptin levels.