Objective

     To determine the effect of bone morphogenetic proteins-13 (BMP-13) on mesenchymal stem cells (C

3

H10T

1/2

) differentiating into cardiomyocyte-like cells

in vitro

.     Methods      C

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cells were transfected with recombinant adenovirus plasmids pAdEasy-BMP-13

pAdEasy-BMP-2 (positive control)

or AdEasy-GFP (negative control). The expressions of cardiac-specific proteins cardiac isoform of tropnin T (cTnT) and connexin 43 (Cx43) in the above transfected and non-transfected C

3

H10T

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cells were measured by Western blotting

the expressions of cardiac-specific proteins α-MHC and α-actin were detected with immunofluorescence staining and the expressions of cardiac-specific genes GATA4 and MEF2C were detected by real-time quantitative PCR at 3 week after transfection. The ultrastructure of the cells was observed by electron microscopy in 4 weeks after the transfection.     Results     After pAdEasy-BMP-13 transfection

C

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cells began to stretch

with obviously enhanced refractivity

and close interconnection of cells in a regular order. Positive expressions of cTnT

Cx43

α-MHC and α-actin were found in pAdEasy-BMP-13 and pAdEasy-BMP-2 plasmids transfection groups in 3 weeks after transfection

but not in 1 and 2 weeks. Neither was found in AdEasy-GFP transfection groups and non-transfected group at 1

2 and 3 weeks. The expressions of GATA4 and MEF2C were detected in all cell groups

but more strong in pAdEasy-BMP-13 and pAdEasy-BMP-2 transfection groups than in AdGFP plasmid transfection and control group at week 3 (

P

<

0.05). C

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cells after pAdEasy-BMP-13 transfection displayed myocardial leap dish and myofilament-like structure after 4 weeks’ transfection

but not in pAdEasy-GFP group and control group at the same time point.     Conclusion     pAdEasy-BMP-13 probably promote the differentiation of stem cells into cardiomyocytes.