Abstract: Objective To study the effect and mechanism of Akt during Islet-1 inducing the mesenchymal stem cells of C3H10T1/2 cells to differentiate specifically into cardiomyocytes. Methods Constructing the model of Islet-1 over-expression cells, Lentivirus transfection efficiency of cells was detected by flow cytometry detection technology. Cell proliferation was tested by CCK-8. The protein expressions of Islet-1，cTnT and p-Akt/T-Akt were measured by Western blot. The mRNA expression of GATA4，Nkx2.5 and Mef2c were tested by real-time PCR. Results With the increasing of MK – 2206 concentration, the inhibition rate of cell proliferation increased（P<0.05）, and the best inhibition concentration of Akt was 8 nmol/L; With prolongation of Islet-1 inducing time，the protein expression of p-Akt/T-Akt reduced（P<0.05）;The gene expression of myocardial specific transcription factor GATA4, Nkx2.5 and Mef2c increased（P<0.05）；treated with MK-2206, the gene expression of GATA4, Nkx2.5 and Mef2c increased significantly at the first week and then reduced（P<0.05）. Conclusions Akt plays different effects in different differentiation stages during the Islet-1 inducing the cells into cardiac-specific differentiation process.

Key words: islet-1, Akt, MK-2206, mesenchymal stem cells, cardiomyocyte