Acceleration of wound healing by quercetin in diabetic rats requires mitigation of oxidative stress and stimulation of the proliferative phase.

Increased oxidative stress in diabetic wound areas impairs wound healing. Quercetin exhibits significant antioxidant properties. We investigated the effects of topical quercetin on antioxidant status in diabetic wound areas and its effect on wound healing in rats. A 2 cm cutaneous wound was produced on the back of streptozotocin induced diabetic and normal rats. Rats were divided into three groups of 20: normal healthy control group, diabetic group and quercetin treated diabetic group. The control and diabetic groups were treated topically with ointment base once daily for 21 days. The quercetin treated diabetic rats were treated similarly with ointment containing quercetin. The quercetin treated diabetic group exhibited increased levels of catalase, glutathione peroxidase, superoxide dismutase and total thiols compared to the diabetic group. Nitrite levels in the diabetic group were decreased significantly on day 3 compared to the healthy control group. Malondialdehyde levels were decreased in the quercetin treated diabetic group compared to the diabetic group. The expression of proliferating cell nuclear antigen) (PCNA) was greater in the quercetin treated diabetic group on day 7 compared to healthy control and diabetic groups. Formation of granulation tissue and the quality of healed tissue was improved in the quercetin treated diabetic group compared to the diabetic group. Quercetin improves antioxidant status in wounds of diabetic rats and stimulates the proliferation phase, which accelerates wound healing.