MicroRNA profiling analysis revealed different cellular senescence mechanisms in human mesenchymal stem cells derived from different origin.

Mesenchymal stem cells (MSCs) from human umbilical cord (UC) and cord blood (CB) share many common properties and exhibit promising clinical potential. Cellular senescence, which induces the loss of stem cells characters and disrupts their therapeutic functions, has been demonstrated to be under the regulation of microRNAs (miRNAs). In this study, we compared the miRNA profiles in early and late passage UCMSCs and CBMSCs based on deep sequencing. 224 and 170 miRNAs were significantly altered in UCMSCs and CBMSCs respectively. A functional annotation of the predicted miRNA targets revealed a series of common senescence pathways. However, Functional enrichment analysis revealed different bioprocesses involved in cellular senescence of UC- and CB-MSCs. The common miRNAs shared by the two kinds of MSCs also exert different function in terms of GO enrichment analysis. Our results supported MSCs derived from different origin may undergo senescence through different path.