Apolipoprotein E Inhibits Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells by Inhibiting β-Catenin Expression

Abstract

Bone marrow mesenchymal stem cells (BMSCs) can differentiate into adipocytes, osteoblasts. Apolipoprotein E (ApoE) is closely related to bone metabolism and its effect on bone marrow mesenchymal stem cells is unclear. Therefore, this study investigated ApoE's effect on BMSCs osteogenic differentiation. BMSCs were isolated from ApoE – and WT mouse and cultured to induce osteogenic induction followed by analysis of expression of osteogenic differentiation marker genes by Real-time PCR, calcium nodules formation by ARS staining, ALP activity and -catenin protein level by Western blot. The number of bone differentiation markers, ALP activity and calcium nodules formation as well as β-catenin protein level in ApoE– group were significantly elevated compared with WT (P < 0 05). After treatment with DKK-1, β-catenin expression was significantly reduced (P < 0 05) without difference between ApoE– + DKK-1 group and WT group (P > 0 05). WT+ DKK1 group showed significantly reduced osteogenic differentiation marker expression, ALP activity and calcium nodule number compared to WT (P < 0 05) without difference between ApoE– + DKK1 group and WT group (P > 0 05). ApoE inhibits BMSCs osteogenic differentiation by inhibiting β-catenin expression.