Geniposide promotes wound healing of skin ulcers in diabetic rats through PI3K/Akt pathway

Continuously hyperglycation-induced lesion and poor blood flow contributed to the wound incurable and susceptible to infection. About fifteen percent of people with diabetes would develop ulcers during their lifetime, especially on the feet, which could lead to severe tissue destruction and eventual amputation. Various strategies were limited to accelerate wound healing in diabetic patients for high cost and unsatisfied effects. Geniposide is well-known for its anti-inflammation and anti-apoptosis in several pathological tissues. This study is to explore the protective effect of geniposide on wound healing rate, inflammatory response, nutritional function and cellular apoptosis in diabetic rats. Diabetic rats was induced by streptozotocin and defined as plasma glucose >300 mg/dl. Western blot and immunostaining technologies were performed to mark and quantify the target proteins. The oral administration of geniposide (200 mg/kg and 500 mg/kg) could significantly promote wound healing by the increment of lesion retraction in diabetic rats compared to model group. In the apoptotic study of skin wound in diabetic rats, the TUNEL-positive cells were greatly decreased in geniposide subgroups (P < 0.05). The levels of TNF-α, IL-1β and IL-6 were significantly inhibited by geniposide with the IC₅₀ value of 470 mg/kg, 464 mg/kg and 370 mg/kg body weight respectively, which might be related to the enhancement of the phosphorylation of PI3K and Akt proteins. Geniposide enhanced the repairment of skin wound in diabetic rats by inhibiting inflammatory response and apoptosis.