Preparation and cytocompatibility of beta-calcium phosphate scaffolds with tanshinol coating / 中国组织工程研究

ABSTRACT

BACKGROUND: Revascularization is a challenge for the tissue-engineered bone carrying cells after implanted into human body. Previous studies have found that tanshinol can improve the functions of endothelial progenitor cells and exert vascular protective effects.OBJECTIVE: To prepare the β-calcium phosphate (β-TCP) scaffold with tanshinol coating, and to observe its cytocompatibility.METHODS: The β-TCP scaffolds coated with 10-7, 10-6 and 10-5 mol of tanshinol were constructed by negative pressure absorption method. The distribution of tanshinol coating on the scaffold was observed using scanning electron microscopy,and the inner ingredients were analyzed by infrared spectrum. Human endothelial progenitor cells (hEPCs) were cultured in the extracts of β-TCP and β-TCP scaffolds with 10-7, 10-6, 10-5 mol of tanshinol coatings, respectively. The cell proliferation was detected at 2, 4, 6, 8 and 10 days of culture; the levels of nitric oxide and vascular endothelial growth factor in the supernatants were detected at 1, 7 and 14 days of culture; the lumen formation on the matrigel was observed after 14-day culture. hEPCs were respectively seeded onto the β-TCP and β-TCP scaffolds with different dosages of tanshinol coating,and then the cell growth was observed under scanning electron microscope at 7 days.RESULTS AND CONCLUSION: The tanshinol coating evenly distributed on the inner surface of the pores, and its crystalline structure became dense with dosage increasing. Infrared spectrum analysis revealed no changes in the characteristic absorption peak of tanshinol and TCP in the scaffold. The β-TCP scaffolds with tanshinol coating could promote the proliferation of hEPCs, especially the scaffolds with 10-6 and 10-5 mol tanshinol coating. Compared with the β-TCP scaffold, the scaffolds with 10-6 and 10-5 mol tanshinol coating significantly upregulated the nitric oxide level at 14 days of culture, and significantly increased the level of vascular endothelial growth factor at 7 and 14 days of culture (P <0.05). Although it could be found in all β-TCP scaffolds with tanshinol coating, the lumen formation was the maturest in the scaffold with 10-5 mol tanshinol coating. These results suggest the β-TCP scaffolds with tanshinol coating can promote the proliferation and endothelial differentiation of hEPCs, and hold a good cytocompatibility.