Objective: To investigate the role of micro RNA-451 (miRNA-451) in promoting the osteogenesis of mesenchymal stem cells (MSCs) by targeting regulatory calcium binding protein 39 (CAB39).
Methods: pMIR-report and pRL-TK vectors were selected to identify the relationship between miRNA-451 and CAB39 by using dual-luciferase reporter assay. pre-miRNA-451 (group A), anti-miRNA-451 (group C), pre-miRNA negative control (group B), and anti-miRNA negative control (group D) were transfected into the C3H10T1/2 cells, respectively. Then, the cells were collected after osteogenic induction for 7 and 14 days. At 7 and 14 days, the real-time fluorescent quantitative PCR and Western blot assays were performed to detect the related osteogenetic biomarkers [Runx2 and alkaline phosphatase (ALP) mRNA] and expressions of CAB39 protein. At 14 days, the extracellular calcium deposition during the osteogenesis of MSCs was tested by Alizarin red staining method.
Results: CAB39 was the target gene of miRNA-451. At 7 and 14 days after osteogenic induction, the mRNA expressions of Runx2 and ALP in group A were significantly higher than those in group B (P < 0.05), and the expressions in group C was significantly lower than those in group D (P < 0.05). Furthermore, at 14 days after osteogenic induction, the protein expression of CAB39 in group A (0.55 +/- 0.05) was significantly lower than that in group B (1.00 +/- 0.07), and the protein expression in group C (1.21 +/- 0.05) was significantly higher than that in group D (1.00 +/- 0.04), all showing significant difference (P < 0.05). Finally, at 14 days after osteogenic induction, the extracellular calcium deposition in group A was obviously more than that in group B, and group C was downregulated when compared with group D.
Conclusion: miRNA-451 can promote the osteogenesis process of MSCs by downregulating the CAB39.