Improved osteoblast proliferation, differentiation and mineralization on nanophase Ti6A14V

摘要

＜正＞ Background Previous studies have demonstrated increased functions of osteoblasts on nanophase materialscompared to conventional ceramics or composites. Nanophase materials are unique materials that simulate dimensionsof constituent components of bone as they possess particle or grain sizes less than 100 nm. However, to date,interactions of osteoblasts on nanophase materials compared to conventional metals remain to be elucidated. Theobjective of the present in vitro study was to synthesize nanophase metals （Ti6AI4V）, characterize, and evaluateosteoblast functions on Ti6AI4V. Such metals in conventional form are widely used in orthopedic applications.Methods In this work, nanophase Ti6AI4V surfaces were processed by the severe plastic deformation （SPD） principleand used to investigate osteoblast long-term functions. Primary cultured osteoblasts from neonatal rat calvaria werecultured on both nanophase and conventional Ti6AI4V substrates. Cell proliferation, total protein content, and alkalinephosphatase （ALP） activity were evaluated after 1, 3, 7, 10 and 14 days. Calcium deposition, gene expression of type Icollagen （Col-I）, osteocalcin （OC）, osteopontin （OP） and the production of insulin-like growth factor-l （IGF-I） andtransforming growth factor-beta 1 （TGF-β1） were also investigated after 14 days of culture.Results Functions of osteoblasts including proliferation, synthesis of protein, and ALP activity were improved on thenanophase compared to the conventional Ti6AI4V. The expression of Col-I, OC and OP mRNA was also increased onnanophase Ti6AI4V after 14 days of culture. Calcium deposition was the same; the average number of the calcifiednodules on the two Ti6AI4V surfaces was similar after 14 days of culture; however, highly significant size calcifiednodules on the nanophase Ti6AI4V was observed. Of the growth factors examined, only TGF-β1 showed a difference inproduction on the nanophase surface.Conclusion Nanophase Ti6AI4V surfaces improve proliferation, differentiation and mineralization of osteoblast cellsand should be further considered for orthopedic implant applications.