Objective This study aimed to investigate the effects of erythropoietin(EPO) on the differentiation and function of osteoblasts, to identify the roles of EPO-erythropoietin receptor(EPOR) in osteoblasts, and to explore the effects and mechanism of EPO in bone homeostasis. Methods Mouse bone marrow stromal cell line ST2 was cultured in vitro and treated with EPO. Changes in osteoblastic gene levels were quantified by real-time polymerase chain reaction. The function of osteoblasts in bone formation was observed by alkaline phosphatase(ALP) and alizarin red staining. EPOR expression was knocked down by RNA interfere. The differentiation and function of osteoblasts were then tested by the above methods. Results ST2 cells expressed EPOR. After binding with EPOR, EPO induced osteoblast differentiation from bone marrow stromal cells. Expression levels of osteoblast-related genes Runx2, Alp, and Col1 increased. ALP and calcium deposition increased. Expression levels of osteoblast-related genes were repressed after EPOR knockdown. Conclusion EPO promotes the differentiation and function of osteoblasts through EPO-EPOR signaling.
