Crosstalk mechanism of BMP signaling pathway and Wnt signaling pathway in osteogenic differentiation

LUO Gao-bin; LAO Shan; DU Gang; WEI Da-long; YANG Xi-ren; BAI Bin; WEI Hua-liang

doi:10.3969/j.issn.1001-9448.2017.24.019

Abstract：Objective To investigate the crosstalk mechanism between BMP -2/Smad signaling pathway and Wnt/β-catenin pathway in osteogenic differentiation of mouse bone marrow mesenchymal stem cells (MSCs).Methods The recombinant human BMP -2 (rhBMP-2) plasmid was transfected into C3H10T1/2 cells.G418 resistance was applied for transfection screening .The experimental cells were divided into transfected group and blank group ( no plas-mid).The concentration of BMP -2 in medium supernatant was detected by BMP -2 ELISA kit.Western blot and RT-PCR were used to assessed the expression levels of key cytokines , such as Smurf2,β-catenin, phosphorylation β-cate-nin (pβ-catenin), RUNX2, LEF1, Axin and GSK3βin the both 2 groups.Results Compared with the blank group, the concentration of BMP-2 in transfected group was significantly increased and maintained at a high level (P<0.05). The mRNA expression and phosphorylation level of β-catenin were significantly increased in transfected group ( P<0.05).The mRNA expression and protein synthesis of LEF 1 were significantly up-regulated in transfected group (P<0.05).The mRNA expression and protein synthesis of Smurf 2 were significantly reduced in transfected group ( P <0.05).The mRNA expression of GSK3βand Axin2 were down-regulated in transfected group (P<0.05).Conclusion In the osteogenic differentiation process , crosstalk mechanisms exists between BMP -2/Smad signaling pathway and Wnt/β-catenin signaling pathway .It increases the expression of β-catenin and promotes the phosphorylation of β-catenin.