Healing effect of andiroba-based emulsion in cutaneous wound healing via modulation of inflammation and transforming growth factor beta 3

Purpose: To evaluate the effects and mechanisms of andiroba-based emulsion (ABE) topical treatment on full-thickness cutaneous wounds in rats. Methods: The wounds were harvested on days 3, 7, 15, and 20 post-surgery. Wound contraction rate, quantitative immunohistochemistry [macrophages, myofibroblasts, capillaries, collagens (col) I and III, transforming growth factor β3β (TGFβ3)], and tensile strength were assessed. Results: Treated wounds were smaller, contracted earlier and had increased angiogenesis, fewer CD68+ and M2 macrophages on days 7 and 15, but higher on day 20. Myofibroblasts appeared on days 3 to 7 in untreated wounds and on days 7 to 15 in treated wounds. TGFβ3 levels were higher in the treated wounds, less dense collagen fibers, lower col I/III ratios and a higher tensile strength. Conclusion: These results demonstrate the important anti-inflammatory role of treatment and the associated modulation of macrophages, myofibroblasts, and TGFβ3 levels. Collagen fibers in the treated wounds were more organized and less dense, similar to unwounded skin, which likely contributed to the higher tensile strength.