Reduced oral wound healing in the NOD mouse model for type 1 autoimmune diabetes and its reversal by epidermal growth factor supplementation

Using the NOD mouse, a model for type 1 diabetes, we examined how reduced c oncentrations of epidermal growth factor (EGF) in the saliva, after onset o f type I diabetes, affect oral wound healing. Diabetic NOD/LtJ mice on insu lin therapy, prediabetic NOD/LtJ, and age-and sex-matched BALB/cJ mice were given a cutaneous tongue punch and allowed to undergo normal healing. With diabetes onset and a reduction in saliva-derived growth factor levels, the rate of tongue wound healing was reduced compared with nondiabetic NOD/LtJ and healthy BALB/cJ mice. Addition of exogenous EGF to the drinking water did not accelerate the rate of healing in BALB/cJ or prediabetic NOD/LtJ; h owever, diabetic NOD/LtJ mice exhibited accelerated wound healing similar t o healthy mice. These results demonstrate that loss of growth factors from saliva is associated with profoundly reduced oral wound healing, suggesting that therapeutic treatment with topical delivery may be beneficial to pati ents with type 1 diabetes and oral wound complications.