Foam dressing and micropower vacuum dressing promote diabetic foot ulcer wound healing by activating the PI3K/AKT/mTOR pathway in rats

Foam dressing (FD) and micropower vacuum dressing (MVD) have been applied in the treatment of diabetic foot ulcer (DFU). However, research about the mode of action on the efficacy of the two dressings is extremely rare. This study proposed to explore the mechanism involved in diabetic wound healing under FD or MVD treatment. Macroscopical study was performed to evaluate the effectiveness of FD and MVD on wound healing in a rat model of DFU. Morphological analysis in the wound skin tissue was conducted by hematoxylin and eosin staining. Meanwhile, inflammatory cytokines in serum were measured by enzyme linked immunosorbent assay. The protein expression of phosphatidylinositol 3 kinase, protein kinase B and mammalian target of rapamycin (PI3K/AKT/mTOR) and their phosphorylation levels were determined by western blotting. We found that wound healing in rats with DFU was enhanced with the application of FD and MVD. The therapeutic efficacy of FD was superior to MVD. Compared with diabetic foot group, the concentrations of inflammatory cytokines, tumor necrosis factor alpha, interleukin-1β and interleukin-6, were significantly down-regulated. Besides, the phosphorylation levels of PI3K, AKT and mTOR were up-regulated under FD or MVD treatment. We demonstrated that the treatment of FD and MVD effectively promoted the wound skin healing through activating the PI3K/AKT/mTOR pathway. Our research may provide a new idea for exploring the mode of action of dressing application in healing of DFU.