Overexpression of osteoprotegerin promotes preosteoblast differentiation to mature osteoblasts

Abstract

The hypothesis of the present study is that overexpression of osteoprotegerin (OPG) promotes preosteoblast maturation. The preosteoblast cell line MC3T3-E1 was transfected with OPG overexpression. OPG expression was confirmed by enzyme-linked immunosorbent assay (ELISA) and Western blot. Changes in the transcription factors in OPG-expressing cells were assessed by real-time polymerase quantitative polymerase chain reaction (RT-qPCR). Alkaline phosphate (ALP) expression was measured by ELISA. The success of stable transfection of MC3T3-E1 cells with OPG overexpression was confirmed by MoFlow sorting followed by G418 selection. RT-qPCR showed that expression of RunX2, the most important osteoblast differentiation controlling factor, was suppressed. Smad1 and Akt1, as well as ALP, were upregulated in the OPG overexpressing cells. Results from the present study provide evidence that overexpression of OPG in preosteoblasts promotes its differentiation into mature osteoblasts.