TGF-β induced bone marrow mesenchymal stem cells differentiate into cardiomyocyte-like cells

Abstract

Objective To explore the effect of differentiation of rat bone marrow mesenchymal stem cells(MSCs) into cardiomyocyte-like cells in vitro by using transforming growth factor beta(TGF-β).Methods SD rat MSCs were isolated from rat bone marrow and cultured;then the 2nd-generation MSCs were induced by TGF-β1 for 72 h.The cultured cells were observed with phase-contrast microscope for morphological changes.The immunohistochemical technique was used to detect the expressions of desmin,α-sarcomeric actin,CTnT and p38MAPK.GATA-4 and α-MHC expressions were detected by relative quantitative RT-PCR after 7,21 and 28 days of induction,respectively.Results After induction by TGF-β1 for 28 days,MSCs showed fusiform shape,orientating with one accord and forming myotubule-like structure.MSCs induced by TGF-β1 for 28 days could be identified by the positive staining for desmin,α-sarcomeric actin and p38MAPK.The positive rates were all higher than those in the control group.The number was lower in the control group than in the treatment group(P0.01).Relative quantitative RT-PCR showed that in the treatment group GATA-4 expression was weak after 7 days of induction,increased after 21 days of induction and decreased after 28 days of induction.By contrast,α-MHC had no expression after 7 days of induction,but showed weak and obvious expression after 21 days and 28 days of induction,respectively.Conclusion TGF-β may induce MSCs to acquire cardiogenic phenotype.