Objective: To explore the effects of calcitonin gene-related peptide (CGRP) on the migration of bone marrow mesenchymal stem cells (BMSCs) and vascular endothelial growth factor (VEGF) expression in vitro.
Methods: The BMSCs were isolated from Sprague Dawley rats using whole bone marrow adherence method. At 1, 2, and 3 weeks after culture, the expressions of CGRP receptor (CGRPR) was detected by Western blot. The BMSCs were treated with CGRP at concentration 1 x 10(-8) mol/L (experimental group) and did not treated (control group), and the efficacy of BMSCs migration was analyzed by Transwell chamber assay after 72 hours; at 1, 3, 5, and 7 days, the mRNA expressions of vascular cell adhesion molecule 1 (VCAM-1) were detected by real-time fluorescent quantitative PCR; the protein expressions of VEGF were examined using immunohistochemistry and Western blot.
Results: CGRPR expressed stably in the cultured BMSCs and reached the peak at 2 weeks. CGRP had a significantly enhanced role in promoting cell migration. The number of cell migration was (3.20 +/- 1.77) cells/HP in experimental group and (1.11 +/- 0.49) cells/HP in control group, showing significant difference (t = 4.230, P = 0.001). In experimental group, the expressions of VCAM-1 mRNA increased with time and reached the peak at 7 days. There were significant differences in the expressions of VCAM-1 mRNA between control group and experimental group at 3, 5, and 7 days (P < 0.05). Immunocytochemistry results showed positive DAB staining for VEGF at 5 and 7 days in experimental group. Western blot results showed that the protein expressions of VEGF increased significantly at 5 and 7 days in experimental group when compared with control group (P < 0.05), which was signfiantly higher at 5 days than at 7 days in experimental group (P < 0.05).
Conclusion: CGRP can promote the migration of BMSCs and stimulate the protein expression of VEGF, which may plays an important role in regulating bone metabolism by increasing angiogenesis.