Effect of growth differentiation factor 5 on connexin 43 expression during chondrogenic differentiation of mouse bone marrow sternal cells in vitro / 中华创伤骨科杂志

ABSTRACT

Objective To investigate the effect of growth differentiation factor 5(GDF-5)on expression of gap junctional protein,connexin 43,during ehondrogenic differentiation of bone marrow sternal cells(BMSCs)in vitro.Methods BMSCs were isolated from mouse bone marrow and cultured in vitro.The cells in passage 3 were chosen to be induced into chondrogenic differentiation.After induction for 72 hours,TypeⅡcollagen protein was examined by immunocytochemistry and the sulfate glycosaminoglycan was measured by Alcian blue staining.With induction for 24,48 and 72 hours,the proliferation effects of BMSCs were investigated by MTT assay;connexin 43 mRNA and protein were examined by RT-PCR,western blotting and immunocytochemistry respectively at different time points during induction.Results According to MTT assay,GDF-5 had no effect on the proliferation of BMSCs at different time points of induction;RT-PCR,western blotting and immunocytochemistry showed that GDF-5 could promote expressions of connexin 43 mRNA and protein at different times during induction.After 72 hours of induction,immunocytochemistry showed expression of TypeⅡcollagen protein,and AIcian blue staining of proteo- glycan revealed deposition of typical cartilage extracellular matrix.Conclusion GDF-5 can enhance chondrogenic differentiation of mouse BMSCs in vitro by up-regulating the expression of gap junctional protein,connexin 43.