Fatty acid extracts facilitate cutaneous wound healing through activating AKT, ERK, and TGF-β/Smad3 signaling and promoting angiogenesis

Fatty acids (FAs) are potential therapeutic agents for cutaneous wound healing; however, the mechanisms underlying this effect have not been clearly defined. In this study, we extracted and characterized FAs from dried Lucilia sericata larvae and investigated the molecular basis by which FAs promote cutaneous wound healing. We first confirmed that FA sodium salts (FASSs) stimulated proliferation, migration, and tube formation of cultured human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. We then showed that FASSs promoted endothelial-to-mesenchymal transition (EndMT), which plays an important role in stabilizing the neovasculature during angiogenesis. Mechanistically, FASSs up-regulated the expression of angiogenesis-related growth factors, platelet-derived growth factor (PDGF), transforming growth factor-β1 (TGF-β1), and vascular endothelial growth factor A (VEGFA), and activated angiogenesis-related signaling pathways, Akt, ERK, and TGF-β/SMAD3. In a rat acute cutaneous-wound model, FAs promoted wound healing. Following treatment, we further found that expression of anti-apoptosis-related factors (c-Myc and Bcl-2) was up-regulated and expression of apoptosis-related factors (p53 and Bad) was down-regulated. Our findings suggest that FAs can promote cutaneous wound healing by inducing angiogenesis, partly by activating Akt, ERK, and TGF-β/SMAD3 signaling.