Rat BM-MSCs were infected with lentiviral vectors bearing miR-499. The expression of cardiac-specific markers, NKx2.5, GATA4, MEF2C, and cTnI in these cells were examined by rtPCR or Western blot analysis and the activity of the wnt/尾-catenin signaling pathway was evaluated by measuring the phosphorylation status of 尾-catenin.
Over-expression of miR-499 in rat BM-MSCs increased the expression of cardiac-specific genes, such as NKx2.5, GATA4, MEF2C, and cTnI and decreased the ratio of phosphorylated/dephosphorylated 尾-catenin in the wnt/尾-catenin signaling pathway, thus activating the pathway. Knocking down the expression of Dvl, an adaptor molecule in the wnt/尾-catenin signaling, partially blocked the role of the miR-499 and decreased those cardiac-specific genes.
Over-expression of miR-499 in rat BM-MSCs induces them toward cardiac differentiation through the activating the wnt/尾-catenin signal pathway.