miR-1-Mediated Induction of Cardiogenesis in Mesenchymal Stem Cells via Downregulation of Hes-1

Abstract EN

MicroRNAs (miRNAs, miRs) have the potential to control stem cells fate decisions.

The cardiac- and skeletal-muscle-specific miRNA, miR-1, can regulate embryonic stem cells differentiation to cardiac lineage by suppressing gene expression of alternative lineages.

Accordingly, we hypothesized that overexpression of miR-1 may also promote cardiac gene expression in mesenchymal stem cells.

Since Notch signaling could inhibit muscle differentiation, a process in contrast with the effect of miR-1, miR-1-mediated repression of Notch signaling may contribute to the observed effects of miR-1 in mesenchymal stem cells.

Thus, mesenchymal stem cells were infected by lentiviral vectors carrying miR-1, and cells expressing miR-1 were selected.

Alterations in Notch signaling and cardiomyocyte markers, Nkx2.5, GATA-4, cTnT, and CX43, were identified by Western blot in the infected cells on days 1, 7, and 14.

Our study showed that the downstream target molecule of Notch pathway, Hes-1, was obviously decreased in mesenchymal stem cells modified with miR-1, and overexpression of miR-1 promotes the specific cardiac gene expression in the infected cells.

Knockdown of Hes-1 leads to the same effects on cell lineage decisions.

Our results indicated that miR-1 promotes the differentiation of MSCs into cardiac lineage in part due to negative regulation of Hes-1.