Purpose
To induce human Wharton's Jelly mesenchymal stem cells (WJ-MSCs) into neuron-like cells using a modified high-efficient method. Then we investigated the altered expression of miRNAs in the neuronal differentiation of WJ-MSCs.
Methods
MSCs were isolated from the Wharton’s jelly of the human umbilical cord (WJ-MSCs). The immunophenotype of WJ-MSCs was identified by flow cytometry and the capacity for tri-lineage mesenchymal differentiation was confirmed. To induce neuronal differentiation, WJ-MSCs were cultured according to a modified protocol. After a total of 12 days induction, neuronal differentiation efficiency was assessed by Immunocytofluorescent staining and real time PCR. Then miRNA microarray was used to analyze the differentially expressed miRNAs in neuronal differentiation of WJ-MSCs. The results of miRNA microarray were subsequently validated by stem-loop RT-PCR.
Results
After neuronal induction for 12 days, most of WJ-MSCs expressed mature neuronal marker MAP2 (83±7%), and meanwhile some adopted neuronal morphology. Besides, WJ-MSCs expressed Nestin (34±6%), NSE (30±5%), and GFAP (12±3%). We found the mRNA expressions of MAP2, Nestin, NSE and GFAP were significantly increased in the WJ-MSCs derived neuron-like cells. Microarray analysis revealed distinct miRNA profiles in the uninduced WJ-MSCs and WJ-MSCs derived neurons. Totally 28 miRNAs showed more than 5 fold change in expression. Six miRNAs were chosen for further qRT-PCR validation. The results were consistent with the trend of miRNA expression in microarray analysis. Among these 6 miRNAs, four miRNAs (miR-1290, miR-26b, miR-194, and miR-124a) were up-regulated and 2 miRNAs (miR-4521 and miR-543) were down-regulated in the WJ-MSCs derived neurons.
Conclusions
We improved a neuronal induction method of WJ-MSCs, contributing to the possibility of cell-based therapy for neurodegenerative diseases. In addition, we identified the differentially expressed miRNAs in the neuronal differentiation of WJ-MSCs. Our findings suggested that miRNAs might play important roles in the neuronal differentiation of WJ-MSCs.