miR-21 regulates osteogenic and adipogenic differentiation of BMSCs by targeting PTEN

OBJECTIVE: To explore the effects and mechanism of miR-21 on the osteogenic/adipogenic differentiation of mouse BMSCs. METHODS: The bilateral ovaries of C57BL/6J mice (n=24) were removed to construct an osteoporosis model. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-21, osteogenic/adipogenic genes, and PTEN. ALP and ARS and ORO staining were used to detect the formation of calcium nodules and lipid droplets in BMSCs. Western blot was used to detect the expression of PTEN. RESULTS: miR-21 was significantly down-regulated in osteoporotic mice. The expression of miR-21 was significantly up-regulated after the osteogenic induction of BMSCs, and the expression of miR-21 was significantly down-regulated after the adipogenic induction. Overexpression of miR-21 significantly promoted the osteogenic differentiation of BMSCs and inhibits the adipogenic differentiation of BMSCs. CONCLUSION: MiR-21 can promote osteogenic differentiation of BMSCs and inhibit their adipogenic differentiation by negatively regulating PTEN.