HIF1α Promotes BMP9-Mediated Osteoblastic Differentiation and Vascularization by Interacting with CBFA1

Figure 4

Effect of HIF1α and Runx2 on BMP9-induced ectopic osteogenesis after iMEF transplantation into nude mice. (a) BMP9-induced ectopic bone osteogenesis was enhanced by overexpression of HIF1α and Runx2 and inhibited by silencing HIF1α and Runx2. General observation of subcutaneous bone masses in nude mice. (b) Quantitative analysis of osteogenic masses and the relative values of BV/TV, Tb.N, Tb.Sp, Tb.Th, and bone mineral density (BMD) were analyzed (). (c) Subcutaneous osteogenic masses at 5 weeks were subjected to micro-CT analysis to investigate the 3D surface and generate a heatmap of average mineralization density. In the heatmap analysis, white represents the highest average mineral density, and black represents the lowest average mineral density (). (d) The retrieved samples were subjected to histologic staining, and the retrieved samples were fixed, decalcified, paraffin embedded, and subjected to H&E and Masson’s trichrome staining ().

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