miR-146b facilitates the differentiation of induced pluripotent stem cells into neuron-like cells / 中国组织工程研究

ABSTRACT

BACKGROUND: To facilitate the neuronal differentiation of induced pluripotent stem cells (iPSCs) is of great benefit for the repair of nerve injury and nerve regeneration. OBJECTIVE: To investigate the expression of miR-146b in iPSCs differentiation, and its effects on the neural differentiation of iPSCs. METHODS: After 7-day neural induction of mouse iPSCs, the expressions of miR-146b and pluripotent stem cell markers were detected by real-time PCR. Then, we generated miR-146b overexpressing iPSCs followed by the neural induction. The expression of stem cell and neuroectoderm markers were examined by cell immunofluorescence and real-time PCR respectively. Meanwhile, the expression of Tuj-1, a nerve cell marker, was also detected. RESULTS AND CONCLUSION: Compared with the normal iPSCs, the expressions of pluripotent stem cell markers Nanog, Oct4 and Sox2 were significantly down-regulated in iPSCs undergoing 7-day neural induction, while the level of miR-146b was increased obviously. In miR-146b-overexpressing iPSCs, we found that the expression of Oct4 was substantially decreased, while there were no statistical changes in the expression of Nanog and Sox2. Meanwhile, during the neural differentiation, miR-146b overexpression significantly down-regulated the expression of Nanog, Oct4 and Sox2, and up-regulated the expression of neuroectoderm markers, Nestin, Sox1 and Pax6. After 18 days of neural induction, the miR-146b overexpression significantly increased the number of Tuj-1-positive cells. Taken together, miR-146b plays a vital role in facilitating the differentiation of iPSCs into neuron-like cells.