Dexamethasone modulates BMP‐2 effects on mesenchymal stem cells in vitro

Abstract

Dexamethasone/ascorbic acid/glycerolphosphate (DAG) and bone morphogenic protein (BMP)-2 are potent agents in cell proliferation and differentiation pathways. This study investigates the in vitro interactions between dexamethasone and BMP-2 for an osteoblastic differentiation of mesenchymal stem cells (MSCs). Bone marrow-derived human MSCs were cultured with DAG (group A), BMP-2 þ DAG (group B), and DAG þ BMP-2 combined with a porous collagen I/III scaffold (group C). RT-PCR, ELISA, immuncytochemical stainings and flow cytometry analysis served to evaluate the osteogenic-promoting potency of each of the above conditions in terms of cell morphology/viability, antigen presentation, and gene expression. DAG induced collagen I secretion from MSCs, which was further increased by the combination of DAG þ BMP-2. In comparison, the collagen scaffold and the control samples showed no significant influence on collagen I secretion of MSCs. DAG stimulation of MSCs led also to a steady but not significant increase of BMP-2 level. A DAG and more, a DAG þ BMP-2, stimulation increased the number of mesenchymal cells (CD105þ/CD73þ). All samples showed mRNA of ALP, osteopontin, Runx2, Twist 1 and 2, Notch-1/2, osteonectin, osteocalcin, BSP, and collagen-A1 after 28 days of in vitro culture. Culture media of all samples showed a decrease in Ca 2þ and PO 4 2À concentration, whereas a collagen-I-peak only occurred at day 28 in DAG-and DAG þ BMP-2-stimulated bone marrow cells. In conclusion, BMP-2 enhances DAG-induced osteogenic differentiation in mesenchymal bone marrow cells. Both agents interact in various ways and can modify osteoblastic bone formation. ß

Osteogenic differentiation of mesenchymal stem cells is regulated by osteocyte and osteoblast cells in a simplified bone niche

“…However, it is unlikely that these factors include chemicals such as ascorbic acid, dexamethasone and β-glycerol phosphate, which are the key constituents of osteogenic media, as the authors are unaware of any evidence that osteocytes or osteoblasts are capable of secreting such chemicals. It is likely that the are targeting similar proteins to the osteogenic medium additives which are responsible for producing the collagen, BMPs and phosphate secretion required for bone formation (Jäger et al, 2008).…”

Optimal Diameter of Honeycomb Tunnel Structure induces Bone Regeneration and Metabolism by Promoting Angiogenesis for an Implant Circumference Bone Defect

“…The amounts of BMP-2 applied did not appear to enhance implant-osseointegration in large buccal defects. Jäger et al 26) reported that BMP-2 enhances osteogenic differentiation of mesenchymal bone marrow cells in vitro within medium containing dexamethasone, ascorbic acid, and -glycerophosphate. BMP-2 was contained in the osteogenic differentiation culture medium in our experiment.…”

Synergistic effect of recombinant human bone morphogenic protein-7 and osteogenic differentiation medium on human bone-marrow-derived mesenchymal stem cells in vitro

“…Although the effect of dexamethasone on osteogenic differentiation of bone marrow MSCs has been extensively studied for several decades [17][18][19][20][21], the synergistic effect between dexamethasone and BMPs was recently examined. Jäger et al reported that BMP-2 enhanced ODM-induced osteogenic differentiation in human mesenchymal bone marrow cells [22]. A later study conducted in rat dental follicle progenitor cells showed that the joint application of dexamethasone and BMP-2 achieved the highest ALP activity, calcium and phosphonium and osteocalcin content compared with the groups treated with dexamethasone or BMP-2 alone [23].…”