The expression and role of miR-301a in human umbilical cord-derived mesenchymal stromal cells.

Abstract

Toll-like receptors (TLRs) are expressed in human umbilical cord-derived mesenchymal stromal cells (UC-MSCs), and activation of TLRs plays an important role in proliferation, differentiation and immunoregulatory activity of UC-MSCs. We investigated whether TLRs regulated the expression of microRNAs (miRNAs) in UC-MSCs and the role of miRNAs. With miRNA microarray analysis, we demonstrated that the expression of many miRNAs varied when UC-MSCs were stimulated with the ligand of toll-like receptor 4 (TLR4), lipopolysaccharide (LPS). The expression of some miRNAs was verified by polymerase chain reaction. It was found that microRNA-301a (miR-301a) was up-regulated by the ligands of TLR3 and TLR4, LPS and polyinosinic acid:polycytidylic acid poly(I:C). However, the inhibitors of nuclear factor κB NF-κB and interferon regulatory factor 3 IRF3 signal attenuated the effect of LPS and poly(I:C) on miR-301a expression. Over-expression or lower expression of miR-301a affected the cytokine secretion of UC-MSCs. The expression of miR-301a in UC-MSCs was regulated by TLRs, and miR-301a affected the cytokine secretion of UC-MSCs.