Expression of GDF-5 during Limb Skeletal Development of Mice and the effect of GDF-5 on bone marrow mesenchymal stem cells in vitro

摘要

Objective: To investigate the expression of growth differentiation factor 5(GDF-5) during limb skeletal development of mice and the effect of GDF-5 on bone marrow mesenchymal stem cells in vitro. Methods: The expression of GDF-5 mRNA and protein in mouse fetal limb buds were detected in embryonic day 11.5-15.5(E11.5-15.5) by RT-PCR and Western blotting respectively. Type Ⅱ collagen protein was examined with immunocytochemistry and the sulfate glycosaminoglycan was measured by Alcian blue. Results: During early stage of developmental skeletogenesis, the expression of GDF-5mRNA was constant and began with embryos E11.5, highlighted at embryos E12.5 and E13.5, subsequently dropped at embryos E14.5 and E15.5. There was very significant difference(P < 0.01) in average light density ratio of GDF-5/β-actin between E12.5-13.5 and the other three days. The expression of GDF-5 protein had a similar change with mRNA during limb skeletogenesis. Immunocytochemistry showed that GDF-5 could promote expression of Type Ⅱ collagen protein and histological staining of proteoglycan with Alcian blue revealed the deposition of typical cartilage extracellular matrix components. Conclusion: GDF-5 can enhance chondrogenic differentiation of mouse bone marrow mesenchymal stem cells in vitro, which plays an important role in limb skeletal development and joint formation.