Effect of Let-7c on neural differentiation of bone marrow mesenchymal stem cellsin vitro

Wang Jing; Zhao Shao-yun; Li Ming-zhe; Jing Li-jun; Jiao Shu-jie; Peng Tao; Teng Jun-fang; Jia Yan-jie

doi:10.3969/j.issn.2095-4344.2016.01.004

Abstract：BACKGROUND:The microRNAs are involved in regulation of stem cel proliferation, differentiation and aging. To study the effect of Let-7c, a member of Let-7, on the neural differentiation of bone marrow mesenchymal stem cels provides new ideas for stem cel therapy. OBJECTIVE: To investigate the role of Let-7c in the neural differentiation of bone marrow mesenchymal stem cels. METHODS: The lentiviral vectors of Let-7c-up and Let-7c-inhibition were constructed and transfected into rat bone marrow mesenchymal stem cels. Optimal multiplicity of infection was screened. The cels were divided into non-transfected group, negative control group (transfected with empty virus), transfected enhancement group (transfected with LV-rno-Let-7c-up), transfected inhibition group (transfected with LV-rno-Let-7c-5p-inhibition). Bone marrow mesenchymal stem cels were treated with fasudil as an inducer for triggering the cels to differentiate into neurons. The fluorescence expressed by transfected cels was observed under inverted fluorescence microscope. The expression of neuron-specific markers, neuron-specific enolase and microtubule-associated protein 2, were measured by immunocytochemical method. The mRNA expression of microtubule-associated protein 2 was detected by RT-PCR. The cel viability was determined by MTT method. RESULTS AND CONCLUSION:Under the inverted fluorescence microscope, the cels were successfuly transfected with LV-rno-Let-7c-up and LV-rno-Let-7c-5p-inhibition. Fasudil induced bone marrow mesenchymal stem cels to differentiate into neurons. The transfection efficiency and expression levels of neuron-specific enolase and microtubule-associated protein 2 in the transfected enhancement group were significantly higher than those in the negative control group (P < 0.05), while in the transfected inhibition group, they were lower than those in the negative control group (P < 0.05). These findings indicate that the differentiation percentage of bone marrow mesenchymal stem cels is increased by fasudil after transfection with LV-rno-Let-7c-up, and Let-7c may promote the differentiation of bone marrow mesenchymal stem cels into neurons.