TGF-β1Modulates The Phenotype Of Vascular Smooth Muscle Cells From Bone Mesenchymal Stem Cells

BMSCs are a population of multipotent cells,candifferentiate into skin cells、osteoblasts、chondrocytes、myocytes.Stemcells can participate in peripheral vascular regeneration、 repair andreconstruction through differentiated into vascular smooth musclecells.The differentiation is affected by a number of factors, such as growthfactors, extracellular matrix and vascular stress environment. Study findsPDGF, bFGF and other growth factors can be induced differentiation ofBMSCs into vascular smooth muscle cells. In a variety of biochemicalfactors, TGF-β1extensively regulate cell growth, differentiation andmigration, By dependent and non-dependent Smad pathway regulating thegene expression in differentiation, regulating the expression of smoothmuscle cells biomarkers in BMSCs. TGF-β1may be involved in the cyclicstrain inducing the differentiation of stem cells. Vascular tension playsimportant roles in regulating the phenotype of vascular smooth cell,research has shown that TGF-β1can induce stem cells differentiation intovascular smooth muscle, but it is not clear which phenotypic induced into. The vascular smooth muscle cell includes synthesis phenotype andcontractile phenotype. Contractile phenotype is matured than Synthesis,highly differentiated and proliferated, rich in filaments and structuralproteins, Actin have α, β, and γ3types of isoforms, dominated byAlpha-actin. While the proliferation and Division of synthetic is activity,mainly based on β, and γ actin. Calponin is a protein family that hasmultiple functions, shrink class-associated protein, mainly have calponin1,2,3. Calponin1is mostly expressed in the contraction of smooth musclecells, calponin2are present in non-muscle cells and smooth muscle cells,to participate in the proliferation of endothelial cells, cytokinesis; calponin3mainly in nervous tissue, but also expresses in smooth muscle cells.Studies have found that TGF-β1can induce expression of calponin1ofstem cells, but cannot express advanced SMC indicators such as myosinheavy chain (Myosin Heavy Chain) and Myocardin protein.Smooth muscle cells under TGF-β1can be transformated betweensynthesis phenotype and contractile phenotype.This experiment study onthe simulation of natural physiological status of vascular cells, supposedlyTGF-β1can induce rat bone marrow mesenchymal stem cellsdifferentiated into contraction smooth muscle cells. To explore thediversity of phenotypic about smooth muscle cells differentiation fromBMSCs under TGF-β1. Objective:To investigate the effect of TGF-β1modulates thephenotype of smooth muscle cells from bone mesenchymal stem cells.Results:the cultured cells were identificated as BMSCs by FlowCytometry.After induced into osteoblasts,adipocytes and smooth musclecells, BMSCs were multipotent cells.Treated by cyclic strain14days, theexpression levels of TGF-β1group about VSMC makers were muchhigher than Control group,especialy the SM-MHC and calponin1.InTGF-β1group,the mRNA of calponin3increased less than the controlgroup, both mRNA and Western-blot of calponin1had equal variations.Conclusion:TGF-β1can modulate the phenotype of VSMCdifferentiation from BMSCs,the phenotype almost are contractilephenotype.