Role of oxygen free radicals in wound healing

The role of oxygen-derived free radicals in wound healing was examined by estimating the formation of conjugated dienes and malondialdehyde, the peroxidative end-products of free radical-lipid interactions. Three pair of parallel wound were created surgically in each rabbit. Each pair of wounds was treated in a different manner: Alcide, an antimicrobial and anti-inflammatory compound, was applied to the first pair of wounds; ibuprofen, a nonsteroidal anti-inflammatory agent, was used to treat the second pair of wounds; and the third pair of wounds was treated with saline and served as the control. Biochemical and morphologic examinations as well as δ-scintigraphy using Indium-111-oxine-labeled polymorphonuclear leukocytes (PMNs) were performed at day 1 (Group I), day 3 (Group III), and day 6 (Group III). The influx of PMNs in the wounded tissue was found to be a function of the duration of the healing process. Maximum PMN influx occurred at day 1, whereas the least number of PMNs reached the wound at day 6. These results were corroborated with the amounts of malondialdehyde and conjugated diene formation in the wound. Both Alcide and ibuprofen were equally effective in preventing the influx of PMN in the wounds, and resulted in a corresponding inhibition of malondialdehyde and diene formation.