Enhanced Wound Healing Effect of Canine Adipose-Derived Mesenchymal Stem Cells with Low-Level Laser Therapy in Athymic Mice

Abstract

Adipose-derived mesenchymal stem cells (ASCs) are attractive cell source for skin tissue engineering. However, one obstacle to this approach is that the transplanted ASC population can decline rapidly in the recipient tissue. The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on transplanted canine ASCs in a skin wound animal model. LLLT, ASC transplantation (ASCs group) and ASC transplantation with LLLT (ASCs + LLLT group) were applied to the wound bed in athymic mice. Wound healing was assessed by gross evaluation and by hematoxylin and eosin staining. The survival, differentiation and secretion of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) of the ASCs were evaluated by immunohistochemistry and western blotting. The ASCs and ASCs + LLLT groups stimulated wound closure and histological skin regeneration. The ASCs + LLLT group enhanced the wound healing, including neovascularization and regeneration of skin appendages, compared with the ASCs group. The ASCs contributed skin regeneration via differentiation and secretion of growth factors such as VEGF and bFGF. In the ASCs + LLLT group, the survival of ASCs was increased by the decreased apoptosis of ASCs in the wound bed. The secretion of VEGF as well as bFGF was stimulated in the ASCs + LLLT group compared with the ASCs group. These data suggest that LLLT is an effective biostimulator of ASCs in wound healing that enhances the survival of ASCs and stimulates the secretion of VEGF as well as bFGF in the wound bed.