Abstract：OBJECTIVE: To study the effects of miR-124-1 on neuronal differentiation of rat bone marrow mesenchymal stem cells (MSCs). METHODS: MSCs cells were assigned into three groups: control (uninfected and untransfected), miR-124-1+ (infected with miR-124-1), and miR-124-1- (transfected with Anti-rno-miR-124* Inhibitor). MSCs were induced by β-mercaptoethanol (β-ME) to differentiate into neurons. The fluorescence expressed by infected MSCs was observed under an inverted fluorescence microscope. MTT method was used to measure cell survival rate after transfection or infection. Immunocytochemistry, RT-PCR and Western blot methods were used to detect the expression of β3 tubulin, MAP-2 and GFAP 6 days after β-ME induction. RESULTS: The expression of miR-124-1 in the miR-124-1+ group was significantly higher 2 days after infection of lentivirus vector compared with the control group (P<0.01). In the miR-124-1- group, the cell survival rate and the miR-124-1 expression level decreased significantly 24 hrs after transfection of anti-rno-miR-124* inhibitor (P<0.01). After 6 days of β-ME induction, the protein and mRNA expression levels of β3 tubulin and MAP-2 in the miR-124-1+ group were much higher than the other two groups (P<0.01); while the expression levels of β3 tubulin and MAP-2 in the miR-124-1-group were lower than the control group (P<0.01) . The expression of GFAP in the three groups was weak (<1%). CONCLUSIONS: miR-124 might promote neuronal differentiation of rat MSCs.
［5］Woodbury D, Schwarz EJ, Prockop DJ, Black IB. Adult rat and human bone marrow stromal cells differentiate into neurons［J］.J Neurosci Res, 2000, 61(4): 364-370.
［6］Shi Y, Zhao X, Hsieh J, Wichterle H, Impey S, Banerjee S, et al. MicroRNA regulation of neural stem cells and neurogenesis［J］. J Neurosci, 2010, 30(45): 14931-14936.
［7］Cheng LC, Pastrana E, Tavazoie M, Doetsch F. miR-124 regulates adult neurogenesis in the subventricular zone stem cell niche［J］. Nat Neurosci, 2009, 12(4):399-408.
［8］Lim LP, Lau NC, Garrett-Engele P, Grimson A, Schelter JM, Castle J, et al. Microarray analysis shows that some microRNAs downregulate large numbers of target mRNAs［J］. Nature, 2005, 433(7027): 769-773.
［9］Yoo AS, Sun AX, Li L, Shcheglovitov A, Portmann T, Li Y, et al. MicroRNA-mediated conversion of human fibroblasts to neurons［J］. Nature, 2011, 476(7359): 228-231.
［10］Ambasudhan R, Talantova M, Coleman R, Yuan X, Zhu S, Lipton SA, et al. Direct reprogramming of adult human fibroblasts to functional neurons under defined conditions［J］. Cell Stem Cell, 2011, 9(2): 113-118.
［11］Conaco C, Otto S, Han JJ, Mandel G. Reciprocal actions of REST and a microRNA promote neuronal identity［J］. Proc Natl Acad Sci U S A, 2006, 103(7): 2422-2427.
［12］Boutz PL, Stoilov P, Li Q, Lin CH, Chawla G, Ostrow K, et al. A post-transcriptional regulatory switch in polypyrimidine tract-binding proteins reprograms alternative splicing in developing neurons［J］. Genes Dev, 2007, 21(13):1636-1652.
［13］Wang C, Yao N, Lu CL, Li D, Ma X. Mouse microRNA-124 regulates the expression of Hes1 in P19 cells［J］. Front Biosci (Elite Ed), 2010, 2:127-132.
［14］Jing L, Jia Y, Lu J, Han R, Li J, Wang S, et al. MicroRNA-9 promotes differentiation of mouse bone mesenchymal stem cells into neurons by Notch signaling［J］. Neuroreport, 2011, 22(5): 206-211.
