20(S)-hydroxycholesterol and simvastatin synergistically enhance osteogenic differentiation of marrow stromal cells and bone regeneration by initiation of Raf/MEK/ERK signaling

• Published in: Journal of materials science. Materials in medicine Vol. 30; no. 8; pp. 87 - 13
• Main Authors: Huang, Yinghe, Lin, Yao, Rong, Mingdeng, Liu, Weizhen, He, Junbing, Zhou, Lei
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2019; Springer Nature B.V
• Subjects: Additives; Alkaline Phosphatase - metabolism; Animals; Apoptosis; Biocompatibility; Biocompatibility Studies; Biomaterials; Biomedical Engineering and Bioengineering; Biomedical materials; Bone growth; Bone healing; Bone marrow; Bone morphogenetic protein 2; Bone Regeneration - drug effects; Bone Regeneration - physiology; Calcium; Cell differentiation; Cell Differentiation - drug effects; Cell Differentiation - genetics; Cell Survival - drug effects; Cell viability; Cells, Cultured; Ceramics; Chemistry and Materials Science; Composites; Differentiation (biology); Drug Synergism; Extracellular signal-regulated kinase; Gene expression; Genes; Glass; Hydroxycholesterols - pharmacology; Male; MAP Kinase Signaling System - physiology; Materials Science; Mesenchymal Stem Cells - drug effects; Mesenchymal Stem Cells - physiology; Mineralization; Natural Materials; Osteogenesis; Osteogenesis - drug effects; Osteogenesis - genetics; Polymer Sciences; Rabbits; raf Kinases - metabolism; Raf protein; Rats; Rats, Wistar; Regeneration; Regeneration (physiology); Regenerative Medicine/Tissue Engineering; Sedimentation; Signal Transduction - drug effects; Signaling; Simvastatin; Simvastatin - pharmacology; Stromal cells; Supplements; Surfaces and Interfaces; Synergistic effect; Thin Films
• ISSN: 0957-4530; 1573-4838
• DOI: 10.1007/s10856-019-6284-0

Previous studies have demonstrated the significant roles of simvastatin (SVA) and oxysterols in the osteogenesis process. In this study, we evaluate the effect of a combination of SVA and 20(S)-hydroxycholesterol (20(S)OHC) on the cell viability and osteogenic differentiation of bone marrow stromal cells (BMSCs). After treatment with a control vehicle, SVA (0.025, 0.10, 0.25 or 1.0 μM), 20(S)OHC (5 μM), or a combination of both (0.25 μM SVA + 5 μM 20(S)OHC), the proliferation, apoptosis, ALP activity, mineralization, osteogenesis-related gene expression and Raf/MEK/ERK signaling activity in BMSCs were measured. Our results showed that high concentrations of SVA (0.25 and 1.0 μM) enhanced osteogenesis-related genes expression while attenuating cell viability. The addition of 5 μM 20(S)OHC induced significantly higher proliferative activity, which neutralized the inhibitory effect of SVA on the viability of BMSCs. Moreover, compared to supplementation with only one of the additives, combined supplementation with both SVA and 20(S)OHC induced significantly enhanced ALP activity, calcium sedimentation, osteogenesis-related genes (ALP, OCN and BMP-2) expression and Raf/MEK/ERK signaling activity in BMSCs; these enhancements were attenuated by treatment with the inhibitor U0126, indicating a significant role of Raf/MEK/ERK signaling in mediating the synergistically enhanced osteogenic differentiation of BMSCs by combined SVA and 20(S)OHC treatment. Additionally, histological examination confirmed a synergistic effect of SVA and 20(S)OHC on enhancing bone regeneration in a rabbit calvarial defect model. This newly developed SVA/20(S)OHC formulation may be used as an osteoinductive drug to enhance bone healing.