Short-term specialized enteral diet fails to attenuate malnutrition impairment of experimental open wound acute healing

Abstract Objective We assessed the effect of enteral refeeding on the morphology, gene expression, and contraction of acute open wounds in previously malnourished rats using two different enteral diets. Methods Adult male isogenic Lewis rats divided into two groups (eutrophic, n = 30; and previously malnourished, 12–15% body weight loss, n = 27) were subjected to cutaneous dorsal wounds and gastrostomy. Control rats received a standard oral diet (AIN-93M chow) plus enteral saline solution. Subject rats received chow plus a standard enteral diet or an enteral diet enriched with arginine and antioxidants. On post-trauma days 7 and 14, wound granulation tissue samples were collected for morphologic analysis using hematoxylin and eosin and picrosirius stain or immunohistochemistry slides and real-time polymerase chain reaction for collagen I and III gene expression. Wound contraction was also evaluated by comparing wound images from days 0, 7, and 14. Results Malnourished control rats had increased intensity and duration of wound inflammation, impaired increase of fibroblast cells contingent on post-trauma days 7 to 14, decreased expression of collagen III, and less wound contraction compared with eutrophic control rats. A specialized enteral diet did not improve wound healing of malnourished rats but did promote wound contraction at post-trauma day 7 in eutrophic rats. Conclusion Short-term enteral refeeding, even with a specialized diet, failed to protect previously wounded malnourished rats from a prolonged inflammatory phase and impaired healing.