Expression of Glial Cell Line-Derived Neurotrophic Factor during Differentiation of Rat Bone Marrow Stromal Cells into Nerve Cells

Objective To investigate neural differentiation of rat bone marrow stromal cells(BMSCs) and expression of change of glial cell line-derived neurotrophic factor(GDNF).Methods BMSCs were harvested from rats and cultured in DMEM supplemented with 100 mL/L fetal bovine serum (FBS).They were characterized by flow cytometry of CD90 and CD45.At passage 4,BMSCs were induced by basic fibroblast growth factor(bFGF,10 μg/L),epidermal growth factor(EGF,10 μg/L) and both of them in DMEM with 100 mL/L FBS for 7 days,respectively.The expression of neural specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were detected by immunocytochemistry.The expression of GDNF and RET mRNA were detected by reverse transcription-polymerase chain reaction(RT-PCR).Results BMSCs at passage 4 were CD90 positive and CD45 negative on flow cytometry.After 7 days of induction,a certain number of cells showed expressions of GFAP and NSE by immunocytochemistry method in experimental group,while the cells showed no expressions of GFAP and NSE in control group.In bFGF group and bFGF plus EGF group,the positive rate of NSE was significantly higher than EGF group,while expression of GFAP in EGF group was obviously higher.BMSCs expressed low level GDNF mRNA and no RET mRNA,however,after induction,GDNF mRNA highly increased and RET mRNA expressed,especially in bFGF plus EGF group.Conclusions bFGF and EGF can not only induce neural differentiation of BMSCs,but also increase the expressions of GDNF and RET significantly.GDNF may play an important role in the process of differentiation of BMSCs into nerve cells.