| Objective To explore the effect of miR-21 on the proliferation of bone marrow stromal cells (BMSCs) in osteoporosis mice. Methods The osteoporosis mice model was constructed with bilateral ovariectomy (OVX) method. BMSCs were separated, cultured, and purified. They were transfected with pre-miR-21, pre-miR-negative control (pre-miR-NC), ant-miR-21, and ant-miR-negative control (ant-miR-NC), respectively, with siPORT NeoFX. RT-PCR verification was conducted. The proliferation of BMSCs was detected with MTT. The osteogenic ability of BMSCs was detected with Alizarin red staining and alkaline phosphatase staining. The levels of cells proliferation and osteogenic differentiation-related proteins were detected with Western blotting. Results The relative expression level of miR-21 in BMSCs of osteoporosis mice was lower than that in Ctrl group (P<0.05). The relative expression levels of miR-21, cell proliferation, PCNA, Ki67, ALP staining, ALP activity, Alizarin red staining, Runx2, and Osterix in OVX- pre-miR-21 group were higher than those in OVX-pre-miR-NC group (P<0.05), and were significantly lower in OVX-pre-miR-NC group than in Ctrl-pre-miR-NC (P<0.05). The relative expression levels of miR-21, cell proliferation, PCNA, Ki67, ALP staining, ALP activity, Alizarin red staining, Runx2, and Osterix in OVX-ant-miR-21 group were significantly lower than those in OVX-ant-miR-NC group (P<0.05), and were significantly lower in OVX-ant-miR-NC group than in Ctrl-ant-miR-NC (P<0.05). Conclusion Increasing the expression level of miR-21 promotes BMSCs proliferation and osteogenic differentiation in osteoporosis mice. |