miR ‐140‐5p‐mediated regulation of the proliferation and differentiation of human dental pulp stem cells occurs through the lipopolysaccharide/toll‐like receptor 4 signaling pathway

Human dental pulp stem cells (DPSCs) are oral mesenchymal stem cells with potential to differentiate into various cell types. Recent studies of DPSCs have focused on microRNAs (miRNAs), a class of small noncoding RNAs that play crucial roles in regulating DPSC phenotypes. In the current study, the expression of miR‐140‐5p was significantly decreased during lipopolysaccharide (LPS)‐mediated differentiation of DPSCs in vitro. Overexpression of miR‐140‐5p enhanced proliferation of DPSCs and inhibited DPSC differentiation, whereas suppression of miR‐140‐5p produced the opposite effect. Moreover, the expression of toll‐like receptor 4 (TLR‐4), a critical regulator of DPSCs, was negatively correlated with the levels of miR‐140‐5p. A luciferase reporter analysis confirmed that miR‐140‐5p could regulate TLR‐4 by directly binding to the 3′‐untranslated region (3′‐UTR) of the TLR4 mRNA. Additionally, we suppressed TLR‐4 expression by treating cells with a TLR‐4 inhibitor, CLI‐095, and demonstrated that the effect of the miR‐140‐5p inhibitor on DPSC proliferation and differentiation could be partially reversed by blocking TLR‐4. Taken together, our data suggest that miR‐140‐5p is a novel miRNA that regulates DPSC proliferation and differentiation.
Source: European Journal of Oral Sciences - Category: Dentistry Authors: Tags: Original Article Source Type: research