Core-binding factor beta is required for osteoblast differentiation during fibula fracture healing

Abstract

Background: Growing evidence has implicated core-binding factor beta (Cbfb) as a contributor to the osteoblast differentiation, which plays a key role in fracture healing. Here, we conducted the present study with the main objective to assess whether Cbfb affects osteoblast differentiation after fibula fracture. Methods: Initially, Cbfb conditional knockout mouse model was established. Immunohistochemical staining was carried out to detect the expression of proliferating cell nuclear antigen (PCNA) and Collagen II in the fracture end. Then osteoblasts were isolated from specific Cbfb conditional knockout mice and cultured. BrdU method, Alkaline phosphatase (ALP) staining and Von Kossa staining were followed to detect osteoblast proliferation, differentiation and mineralization, respectively. Western blot analysis and RT-qPCR were used to detect the expression of osteoblast differentiation-related genes. Cbfb conditional knockout mouse model was successfully constructed. Results: The mice treated with Cbfb knockout were shown to exhibit significantly decreased expression of PCNA and Collagen II, ALP activity and mineralization, as well as inhibited expression of Runx2, ALP, BglaPl, SPPl, Osteocalcin, Atf4 and Osterix. Further, Cbfb knockout showed no effects on osteoblast differentiation. Conclusion: Overall, these results demonstrated that the Cbfb could potentially promote fibula fracture healing and osteoblast differentiation and thus could comprise a potential means of impeding the progression of fibula fracture.