MiR-203 is involved in osteoporosis by regulating DKK1 and inhibiting osteogenic differentiation of MSCs.

ABSTRACT

OBJECTIVE: To investigate whether miR-203 is involved in the osteogenic differentiation of rat mesenchymal stem cells (MSCs) by regulating DDK1, thus participating in the pathogenesis of osteoporosis. PATIENTS AND METHODS: miR-203 expression in serum samples of 60 osteoporosis patients and 60 normal subjects was detected using Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) assay. MSCs were isolated from bone marrow of rats and then identified. Subsequently, the effects of miR-203 and DKK1 on osteogenic differentiation were estimated by alkaline phosphatase (ALP) activity, alizarin red staining, ALP staining, respectively. Expression levels of osteogenic-specific genes were detected by Western blot. Rescue experiments were conducted to confirm whether miR-203 could promote osteogenic differentiation of MSCs by inhibiting DKK1. RESULTS: Serum level of miR-203 in osteoporosis patients was significantly lower than that of the normal subjects. Overexpressed miR-203 in MSCs enhanced ALP activity, expression of osteogenic marker genes and the number of calcified cells. Additionally, miR-203 could bind to DKK1. The regulatory effect of miR-203 on osteogenic differentiation in MSCs was reversed by DKK1. CONCLUSIONS: MiR-203 promotes the differentiation of rat MSCs into osteoblast-like cells, which may be associated with the regulation of DKK1 expression.