Study of the effect of PAPA NONOate on the rate of diabetic wound healing

Abstract

To investigate the effect of exogenous nitric oxide donor (PAPA NONOate) a drug which spontaneously release nitric oxide on the rate of wound healing and collagen synthesis on impaired wound healing in experimental diabetes. 12 male Sprague – Dawley rats were transferred to separate metabolic cages. Nine days before wounding, the rats were injected intraperitoneally (IP) with streptozotocin (STZ) (55 mg/kg body weight in citrate buffer 0.1 mol/L, pH 4.5) to induce diabetes. The dorsal surface of each rat was properly shaved and given full thickness dermal wound. The test group (n = 6) was treated with 100 μmole PAPA NONOate in phosphate buffer while control wounds (n = 6) received sterile phosphate buffer on the same day and every three days. Daily urine samples were collected at every 24 h intervals. To inhibit bacterial growth, 5 ml of 3 M HCl was added to each urine collection (pH = 1) and urine samples were kept frozen until analyzed (-70°C). Urinary nitrate (NO^-3) was quantitated daily prior to wounding, and during wound healing (21 days) following external wound closure. The rate of wound healing was determined by video image analysis. PAPA NONOate treatment increased the rate wound healing in test group as compared to the control group. The nitric oxide donor PAPA NONOate may represent a potential treatment for impaired wound healing in diabetes by increasing the rate of collagen synthesis at the wound site.

Key words: Wound healing, PAPA NONOate, diabetic wound.