[Effects of cardiotrophin-1 on differentiation of cardiomyocyte-like cells induced from rat bone marrow mesenchymal stem cells]

Abstract

Objective: To investigate the effects of cardiotrophin-1 (CT-1) on differentiation of induced rat bone marrow mesenchymal stem cells (BMMSCs) in vitro with 5-azacytidine (5-aza) for the purpose of elucidation of the cellular biological mechanisms.

Methods: BMMSCs isolated from femur of rats were divided into four groups: untreated group as control (group A); 0.1 nmol/L CT-1 added to medium (Group B); induced with 10 micromol/L 5-aza only (Group C); induced with 10 micromol/L 5-aza combined with 0.1 nmol/L CT-1 added to medium (Group D). After 4 weeks of induced culturing, the differentiation of induced myocyte like cells were estimated, levels of cardiac troponin-T (cTnT) by immunohistochemical staining and ultrastructure of induce-cultured BMMSCs were determined and mRNA expression of alpha-actin, beta-myosin heavy chain (beta-MHC), Nkx2.5, GATA4 were analyzed by real time polymerase chain reaction (RT-PCR).

Results: After 4 weeks of induced culturing, morphological characteristics of myocyte like cells with the expression of cTnT were observed in group C and D cells. Higher level expression of GATA4, Nkx2.5, alpha- actin and beta-MHC mRNA in group D was observed by comparing with those of group C and the differentiated BMMSCs with formations of myofilaments distinctly were also existed in 5-aza combined with CT-1 treatment group.

Conclusion: This study suggests that induced culturing of BMMSCs in the presence of 5-aza combined with CT-1 can enhance cardiomyocytic characteristics. CT-1 upregulates the expression of GATA4, Nkx2.5, alpha-actin and beta-MHC mRNA, and rapidly promotes the differentiation and maturation of cardiomyocyte-like cells differentiated from BMMSCs induced with 5-aza.