miR-218 Regulates Glycogen Synthase Kinase-3β and Promotes Differentiation of Human Bone Marrow Mesenchymal Stem Cells into Osteoblasts

miR-218 is associated with osteogenesis. Bioinformatics analysis showed a targeting relationship between miR-218 and GSK-3 beta 3'-UTR. Our study assessed whether miR-218 regulates GSK-3 beta expression and affects osteoblast differentiation of bone marrow mesenchymal stem cells (BMSCs). Osteogenic induction medium was used to induce BMSCs to differentiate into osteoblasts. miR-218, GSK-3 beta, beta-catenin and RUNX2 level was detected during D10 and D20 differentiation. BMSCs cells were divided into antagomir-NC and antagomir-218, and induced to differentiate for 20 days followed by analysis of GSK-3 beta, beta-catenin and RUNX2 level, osteogenesis and cell differentiation by the alizarin red staining. Compared with pre-differentiation, the expression of miR-218, beta-catenin and RUNX2 was gradually increased and GSK-3 beta expression was decreased during the differentiation of BMSCs into osteoblasts. There was a targeted regulation relationship between miR-218 and GSK-3 beta. Compared with the antagomir-NC group, GSK-3 beta protein expression was increased in antagomir-218 transfection group, with decreased the expression of beta-catenin and RUNX2 protein, reduced ALP activity as well as weakened staining degree of alizarin red. GSK-3 beta expression is decreased and miR-218 expression is increased during osteoblast differentiation of BMSCs. Inhibition of miR-218 expression can up-regulate GSK-3 beta expression and attenuate the ability of BMSCs to differentiate into osteoblasts.