Mechano-growth factor accelerates the proliferation and osteogenic differentiation of rabbit mesenchymal stem cells through the PI3K/AKT pathway

Background: Mesenchymal stem cells (MSCs) can differentiate into chondroblasts, adipocytes, or osteoblasts under appropriate stimulation. Mechano-growth factor (MGF) reportedly displays a neuroprotective effect in cerebral regions that were exposed to ischemia and is expressed in stromal cells of the eutopic endometrium and in glandular cells of the ectopic endometrium. Results: This study sought to understand the potential involvement of phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) in MGF-induced growth of rabbit MSCs (rMSCs). We applied various concentrations of MGF to cultured rMSCs and observed the growth rate of the cells, the changes in the phosphorylation state of AKT and mammalian target of rapamycin (mTOR), and the expression levels of alkaline phosphatase and osteocalcin. We found that the growth and osteogenic differentiation of MGF-induced rMSCs were promoted primarily by phosphorylated AKT, and that this phosphorylation, as well mTOR phosphorylation, was mediated by the MGF receptor. Conclusion: Our study suggests that MGF promotes the growth and osteogenic differentiation of rMSCs primarily through the PI3K/AKT pathway.