Effects of vascular endothelial growth factor combined with platelet-derived growth factor-bb on the angiogenic and proliferative abilities of bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: Bone tissue engineering provides a new path to treat critical-sized bone defects. However, a stable osteogenesis and osseointegration can only be insured via formation of an intact vascular network, which can achieve satisfactory therapeutic effects. Thereafter, angiogenesis is a challenge and difficulty in bone tissue engineering. OBJECTIVE: To investigate the effect of combined application of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-BB (PDGF-BB) on proliferation and angiogenesis of bone marrow mesenchymal stem cells. METHODS: Bone marrow mesenchymal stem cells from Sprague-Dawley rats were cultured and isolated in vitro, and interfered with different concentrations of VEGF (20, 40, 60, 80, 100, 120 μg/L) and PDGF-BB (20, 40, 60, 80, 100, 120 μg/L) in combination or 100 μg/L VEGF, and 100 μg/L PDGF-BB alone. The optimum concentration of promoting cell proliferation was detected by cell counting kit-8 assay. The expression levels of angiopoietin-1, hypoxia-inducible factor-1α, hepatocyte growth factor and insulin-like growth factor were detected by RT-PCR at 7 and 14 days after intervention. RESULTS AND CONCLUSION: (1) After growth factors were added, the cell proliferative ability was significantly improved, and combined application revealed better effect. The optimal concentration grou was 80 μg/L VEGF+80 μg/L PDGF-BB. (2) Both VEGF and PDGF-BB could promote the mRNA expression levels of angiopoietin-1, hypoxia-inducible factor-1α, hepatocyte growth factor and insulin-like growth factor, and the effect was more obvious in combined application. (3) The mRNA expression levels of hypoxia-inducible factor-1α and hepatocyte growth factor were significantly increased with time (P < 0.05). The mRNA expression levels of angiopoietin-1 and insulin-like growth factor were significantly decreased with time (P < 0.05). (4) In vitro experimental results suggest that VEGF and PDGF-BB at the concentration of 80 μg/L can consistently promote angiogenesis, and the effect of combined application is better than that of single application.