Abstract:

BACKGROUND: 5-azacytidine (5-Aza) has been frequently used to induce bone marrow mesenchymal stem cells (BMSCs) differentiation into cardiomyocyte.
OBJECTIVE: To observe expression of cardiomyocyte-related receptors in cardiomyogenic differentiation of rat BMSCs.
METHODS: BMSCs of passage three were assigned to four groups: group Ⅰ: L-DMEM solution alone was replaced; Ⅱ: L-DMEM solution was replaced after induction of 100 mg/L AST+5 µmol/L 5-Aza for 24 hours; group Ⅲ: L-DMEM solution was replaced after induction of 10 µmol/L 5-Aza for 24 hours; and group Ⅳ: L-DMEM solution was replaced after induction of 5 µmol/L 5-Aza for 24 hours. Culture medium was replaced every 3 days in each group. Differentiated cells were identified after 30 days of induction.
RESULTS AND CONCLUSION: Expression of cardiomyocyte specific proteins Nkx2.5, cTnT and Desmin was detected in groups Ⅲ, Ⅳ and Ⅱ after induction compared with group Ⅰ , with significant differences (P < 0.01). The amount of cTnT and Desmin expression expression was significantly higher in groups Ⅱ and Ⅲ compared with group Ⅳ (P < 0.01). The level of Nkx2.5 expression was significantly higher in groups Ⅱ (P < 0.01) and Ⅲ (P < 0.05) compared with group Ⅳ. No Nkx2.5, cTnT and Desmin espression was detected in group Ⅰ. After induction for 2 weeks, cells with spontaneous contractility were observed in groups Ⅱ and Ⅲ, indicating differentiation towards cardiomyocyte after induction. Results demonstrated that induction effects were similar between 100 mg/L AST+5 µmol/L 5-Aza and 10 µmol/L 5-Aza. This may contribute to cytoprotective effects of AST, which can promote vascular endothelial cell proliferation, enhance celss tolerance to 5-Aza-induced cytotoxicity and upregulate cardiac-specific protein expression.