Osteogenesis of bone marrow mesenchymal stem cells on hydroxyapatite/icariin/poly(Lactic-co-glycolic acid) scaffolds / 中国组织工程研究

ABSTRACT

BACKGROUND: Bone tissue engineering has provided a novel ideal for treating bone defects in clinic. This study is the first to combine traditional Chinese medicine with the nanostructures of tissue-engineered scaffolds in order to explore and construct a new bone tissue substitute material for the treatment of bone defects. OBJECTIVE: To investigate the osteogenic activity of icariin (ICA)/hydroxyapatite (HA)/poly(lactic-co-glycolic acid) (PLGA) composite scaffolds. METHODS: A HA/PLGA composite scaffold was prepared by physical blending of HA and PLGA, and was then soaked in ICA solution of different concentrations to obtain the HA/ICA/PLGA scaffold. Rabbit bone marrow mesenchymal stem cells were used to evaluate the cell adhesion, proliferation, osteogenesis and cytotoxicity of the composite scaffold. The cell adhesion, proliferation and cytotoxicity were detected by MTT method. The activities of alkaline phosphatase and osteocalcin were detected by ELISA. The expression levels of osteogenic genes and proteins were detected by fluorescence quantitative PCR and western blot assay, respectively. RESULTS AND CONCLUSION: Adding appropriate amount of HA into PLGA could improve the mechanical strength of the scaffold, and 10% HA had the best effect with tensile strength of (1.67±0.37) MPa, and compression modulus of (4.17±1.62) MPa, and nanostructure would be formed on the surface of the scaffold. The nanostructure could promote the adhesion of bone marrow mesenchymal stem cells on the surface of the scaffold. ICA did not affect the proliferation of bone marrow mesenchymal stem cells on the composite scaffold. However, the HA/PLGA composite scaffold soaked in 1.00 µmol/L ICA aqueous solution had the optimal osteogenic differentiation function, and the expression levels of alkaline phosphatase, osteocalcin, osteogenic related genes and proteins (Runx-2 and COL I) were increased. The ICA/HA/PLGA scaffold had no cytotoxicity. These results suggest that HA (10%)/ICA (1.00 µmol/L)/PLGA scaffold has good mechanical properties, osteogenesis and biocompatibility, which has the potential to be a favorable scaffold for bone tissue engineering.