MicroRNA-21 regulates Osteogenic Differentiation of Periodontal Ligament Stem Cells by targeting Smad5

Abstract

Human periodontal ligament stem cells (hPDLSCs) are mesenchymal stem cells (MSCs) derived from dental and craniofacial tissues that exhibit high potential for differentiation into osteoblasts. Recently, microRNAs (miRNAs) have been established to play important roles in MSC osteogenesis. In the current study, we report that miR-21 was down-regulated in osteogenically differentiated PDLSCs. Overexpression of miR-21 significantly inhibited osteogenesis of hPDLSC, whereas its inhibition demonstrated the opposite effects. Furthermore, SMAD family member 5 (Smad5) was predicted to be a downstream target of miR-21 and was shown to undergo up-regulation in PDLSCs induced toward osteogenesis. Moreover, Smad5 and Runx2, which are the critical transcription factors in osteogenic differentiation, were predicted to be targets of miR-21. Suppression of miR-21 expression increased the level of Smad5 in vitro and during in vivo transplantation experiments. Furthermore, suppression of Smad5 inhibited osteogenic differentiation and decreased the protein level of Runx2. Taken together, these results suggested that miR-21 be mechanistically implicated in the regulation of osteogenic differentiation of hPDLSCs by targeting Smad5.

Mechanical stimulation induced osteogenic differentiation of BMSCs through TWIST/E2A/p21 axis

“…Cell-aggregate lysates were extracted by lysing the cells in by Western and IP protein extraction reagent (Beyotime, China) with a protease inhibitor cocktail (Sigma, U.S.A.) for 5 min on ice, and then the concentration of total protein was determined with BCA protein assay (Keygen Biotech, China) following the manufacturer's recommended protocol [27]. After being heated for 5 min at 100 • C in a loading buffer, loaded 20 mg of each detected protein sample was separated by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) and then was electro-transferred into polyvinylidenedifluoride (PVDF) membranes (Millipore, Billerica, MA, U.S.A.).…”

“…Bound primary antibodies were detected by incubating for 1 h with horseradish peroxidase-conjugated goat anti-mouse or anti-rabbit IgG (CWBio, China). The membranes was washed and developed using a ECL Reagent (Millipore, U.S.A.) following the manufacturer's recommended protocol [27], and were quantified using the Image-Quant software.…”

MicroRNA and Human Bone Health

“…MiR‐21 was reported to stimulate osteoblastic differentiation of MSCs through the PI3K/β‐catenin pathway in human umbilical cord MSCs . Yet, in human periodontal ligament stem cells (hPDLSCs), decreased expression of miR‐21 was observed during osteogenesis . At this point, evidence from functional studies showed consistently a positive role of miR‐21 in osteoclastogenesis; however, its role in osteoblast differentiation remained controversial.…”

Osteogenic potential of zingerone, a phenolic compound in mouse mesenchymal stem cells

“…MicroRNAs (miRNAs) are small, single‐stranded, noncoding, endogenous RNAs that lead to ubiquitous regulation of gene expression posttranscriptionally by targeting 3′UTR of mRNAs . Biological and pathological processes controlled by them are cell proliferation, differentiation, growth, cell cycle, apoptosis, and metabolism.…”

“…3 MicroRNAs (miRNAs) are small, single-stranded, noncoding, endogenous RNAs that lead to ubiquitous regulation of gene expression posttranscriptionally by targeting 3 0 UTR of mRNAs. 4,5 Biological and pathological processes controlled by them are cell proliferation, differentiation, growth, cell cycle, apoptosis, and metabolism. Osteoblast differentiation and maturation are typically controlled by miRNAs, which play a role in upregulation and downregulation of gene expression.…”