Abstract: Objective To investigate the role of P38MAPK in BMP-13-induced differentiation of C3H10T1/2 cells into cardiomyocyte-like cells. Methods The four parts of experiment are grouped as follows:1.BMP-13 adenovirus (Ad-BMP-13) on the role of P38MAPK:Ad-BMP-13 transfection group, Ad - GFP transfection group and C3H10 blank group. The phosphorylated P38MAPK (p-P38MAPK) and total P38MAPK (t-P38MAPK) were detected by Western blot . The positioning of p-P38MAPK was detected by immunofluorescence technique;2. P38 MAPK interference adenovirus (Ad-si-P38) on the role of P38MAPK:si-P38 interference group,si-NC control interference group and C3H10 blank group. The t-P38MAPK was detected by Western blot.3. The influence of BMP-13 induced differentiation after Ad-si-P38 blocking P38MAPK signal pathway:si-P38+Ad-BMP-13 transfection group,si-NC+Ad-BMP-13 transfection group,si-NC+Ad-GFP transfection group and C3H10 blank group.The cTnT and Cx43 were detected by Western blot and the GATA-4 and MEF-2C were detected by fluorescent quantitative PCR.4. The influence of BMP-13 induced differentiation after SB203580 blocking P38MAPK signal pathway: DMSO+Ad-BMP-13 transfection group,SB203580(2,5 and 10μmol/L)+ Ad-BMP-13 transfection group.The GATA-4 and MEF-2C were detected by by fluorescent quantitative PCR.Results BMP-13 promoted the P38MAPK phosphorylation. Ad-si-P38 can effectively lower the P38MAPK expression. Ad-si-P38 which can block P38MAPK signal pathway significantly inhibited the BMP-13-induced expression of cTnT,Cx43 (P<0.05) and GATA4,MEF-2C (P<0.05). With the increased concentration of P38MAPK specific inhibitor SB203580, expression of GATA-4,MEF-2C was reduced significantly (P<0.05).Conclusions P38MAPK signal pathway can be activated by Ad-BMP-13 to promote cardiomyocyte -like cells differentiation from C3H10T1/2 cells.

Key words: BMP-13, C3H10T1/2 cells, p38MAPK, RNA interference, SB203580