Polyunsaturated phosphatidylcholine protects against wound contraction in experimental skin burn injury

Polyunsaturated phosphatidylcholine (PP) is a soybean lecithin, whose oral supplementation prevents fibrosis and strictures in animal models. The purpose of the present study was to investigate the effect of PP on wound contraction using a model of skin burn injury. Thirty male Sprague-Dawley rats were randomly divided into three groups: control (C), just burn (JB), and burn treated with PP (BPP). Burns were induced on the dorsum of the rats by a metal plate with a 4-cm(2) contact surface. Ten percent emulsion of PP was given orally for 21 days in BPP group. The effects of PP on burns were evaluated histologically on day 21, and wound contraction was measured by planimetry weekly. Microscopic evaluation included the amount and density of myofibroblasts and collgen type III, the existence of mature collagen fibers in the regenerated dermis, and thickness measurements of the regenerated tissue. There was a significant decrease in mean wound size index in group JB when compared to BPP on days 14 and 21 (p <.05 and p <.01, respectively). After 3 weeks, the granulation tissue was more cell dense, containing high numbers of myofibroblasts in group JB when compared to BPP (p <.05). The wounds had more mature collagen bundles, but less collagen type III in group BPP when compared to JB. Thus, polyunsaturated phospatidylcholine protected against wound contraction and modulated wound healing in the rat model of skin burn injury.