Experimental studies on dedifferentiation of skin fibroblasts induced by mechanical trauma

Chen Zelin; Shi Chunmeng

doi:10.3969/j.issn.1672-8521.2017.02.002

Abstract：Objective:To study whether mechanical trauma could induce dedifferentiation of skin fibroblasts.Methods:The scratch wound model of cells cultured in vitro and the full-thickness skin injury model in vivo were established,and the methodologies of immunofluorescence staining,immunohistochemistry,Western bloting and RNA sequencing,siRNA etc.were employed to detect the morphological change,proliferation,expression of stem cell related markers,colony forming ability and gene expression profile of fibroblasts.Results:Following mechanical trauma,fibroblasts changed themselves into round-small shapes,and were activated to proliferation within 36 hours.The activation was not dependent on the wound severity.The expressions of stem cell markers Sox2 and vimentin and the colony forming ability were dramatically increased following mechanical trauma.There also found a large number of Sox2+ cells in the granulation tissues in the full-thickness wound model.Analysis of gene expression profile showed that the signaling pathway regulating pluripotency of stem cell and related regulating genes were significantly up-regulated.β-catenin and ser 675-phosphorylated β-catenin expressed by fibroblast enhanced 2 hours after mechanical trauma,but the Sox2 positive cells almost disappeared post-injury after β-catenin was inhibited by β-catenin siRNA.Conclusions:Mechanical trauma may induce dedifferentiation of skin fibroblasts,and β-catenin has been found to mediate the mechanical trauma induced dedifferentiation.