Downregulation of β-catenin and Akt signaling is responsible for poor proliferation of the late passage of bone marrow mesenchymal stem cells.

It is well established that mesenchymal stem cells (MSCs) will partially lose their proliferative ability with continuous expansion. However, the specific mechanisms underlying this effect remain unclear. In the present study, it was identified that β-catenin was downregulated in the late passage (passage 8) of bone marrow mesenchymal stem cells (bmMSCs). Following β-catenin expression, the expression of phospho-Akt was also significantly decreased in the late passage of bmMSCs. More notably, overexpression of β-catenin in passage 8 of bmMSCs by transfection with pMXs-β-catenin plasmids, significantly increased cell proliferation and Akt expression. These results indicate that the downregulation of β-catenin and Akt signaling may be a critical factor for the proliferation of the late passage of bmMSCs.