Low-energy CO2 fractional laser treatment for post-burn scars via activating Wnt/β-catenin pathway in scar epithelial cells in rats
Objective To investigate the role of scar epithelial cells and its potential molecular mechanisms in the efficacy of low-energy CO2 fractional laser treating post-burn scars.Methods The model of post-major burn scars on the back of rat was established.Three rats with post-major burn scars received 30 mJ low-energy CO2 fractional laser treatment to detect the activation of scar epidermal cells.Epidermal tissue of scars was isolated for RNA sequencing to screen activated pathways.Subsequently,18 rats with post-major burn scars were randomly divided into 3 groups(n=6):the control group without laser treatment,the laser group receiving 30 mJ CO2 fractional laser treatment,and the laser+inhibitor group receiving laser treatment and intra-scar injection of IWR-1(a Wnt/β-catenin pathway inhibitor),to verify the activation status and effects of the selected pathways.Hematoxylin-eosin staining,Masson staining,and Western blotting were used to detect the proliferation of epithelial cells and fibroblasts,the activation of Wnt/β-catenin pathway,as well as the improvement of scar profiles.Results After low-energy laser treatment,there was a significant increase in the number of Ki67-positive,proliferating cell nuclear antigen(PCNA)-positive,cytokeratin 19(CK19)-positive,and p63-positive cells in the scar epithelial tissue.RNA sequencing coupled with literature analysis identified Wnt/β-catenin pathway as a potential candidate pathway.In the confirmatory experiment,compared to the control group,the Wnt/β-catenin pathway was activated in scar epithelial cells in the laser group 5 d post-laser intervention.After 30 d laser intervention,dermal collagen exhibited a more loosened arrangement,with reduced dermal thickness and significantly less α-smooth muscle actin(α-SMA)-positive fibroblasts compared to the control group.CollagenⅠ,collagen Ⅲ,and the relative ratio of collagen Ⅰ to Ⅲ in the laser group were at a lower level than those in the control group.Administration of the Wnt/β-catenin pathway inhibitor blocked the activation of the Wnt/β-catenin pathway induced by low-energy laser,the proliferation of scar epithelial cells and the improvement of scar profiles.Conclusion Low-energy CO2 fractional laser treatment can activate the Wnt/β-catenin pathway of scar epithelial cells,thereby activating epithelial cells and yielding significant scar improvements.
NETL
NSTL
万方数据
