%0 Journal Article %T Amelogenin Peptide Extract Increases Differentiation and Angiogenic and Local Factor Production and Inhibits Apoptosis in Human Osteoblasts %A Rene Olivares-Navarrete %A Sharon L. Hyzy %A Argelia Almaguer-Flores %A Corinna Mauth %A Anja C. Gemperli %A Barbara D. Boyan %A Zvi Schwartz %J ISRN Biomaterials %D 2013 %R 10.5402/2013/347318 %X Enamel matrix derivative (EMD), a decellularized porcine extracellular matrix (ECM), is used clinically in periodontal tissue regeneration. Amelogenin, EMD¡¯s principal component, spontaneously assembles into nanospheres in vivo, forming an ECM complex that releases proteolytically cleaved peptides. However, the role of amelogenin or amelogenin peptides in mediating osteoblast response to EMD is not clear. Human MG63 osteoblast-like cells or normal human osteoblasts were treated with recombinant human amelogenin or a 5£¿kDa tyrosine-rich amelogenin peptide (TRAP) isolated from EMD and the effect on osteogenesis, local factor production, and apoptosis assessed. Treated MG63 cells increased alkaline phosphatase specific activity and levels of osteocalcin, osteoprotegerin, prostaglandin E2, and active/latent TGF-¦Â1, an effect sensitive to the effector and concentration. Primary osteoblasts exhibited similar, but less robust, effects. TRAP-rich 5£¿kDa peptides yielded more mineralization than rhAmelogenin in osteoblasts in vitro. Both amelogenin and 5£¿kDa peptides protected MG63s from chelerythrine-induced apoptosis. The data suggest that the 5£¿kDa TRAP-rich sequence is an active amelogenin peptide that regulates osteoblast differentiation and local factor production and prevents osteoblast apoptosis. 1. Introduction Enamel matrix derivative (EMD) is a decellularized extracellular matrix (ECM) isolated from porcine tooth germs and has been used clinically in a carrier as Emdogain (Institut Straumann AG, Basel, Switzerland) to promote periodontal tissue regeneration, including periodontal ligament, alveolar bone, and cementum [1¨C3]. It has been suggested that EMD induces periodontal tissue regeneration by mimicking events in normal periodontal tissue development [4]. During tooth formation, enamel matrix proteins are secreted by ameloblasts and Hertwig¡¯s epithelial root sheath. In addition to providing the structural matrix for the developing enamel, these proteins also act as mediators at the epithelial/mesenchymal interface, resulting in formation of periodontal ligament, alveolar bone, and dental cementum [5¨C7]. EMD not only functions as a scaffolding for cell migration and clot organization, but one or more of its constituents also have biological activity associated with wound repair. In addition to its effects on periodontal bone formation, EMD has been applied to long bone defects, increasing de novo trabecular bone formation [8]. It has also been used to heal acute and chronic skin wounds, increasing the amount of granulation tissue and %U http://www.hindawi.com/journals/isrn.biomaterials/2013/347318/