title: Periostin is a negative regulator of mineralization in the dental pulp tissue.
abstract: The dental pulp tissue is encased in hard tissue and surrounded by hard tissue-forming cells, but remains in a non-mineralized state itself, suggesting the presence of regulatory mechanisms precluding pulp mineralization. This study aimed to reveal the regulatory function of periostin (Postn), which is essential for osteoblast differentiation, for odontoblast differentiation/mineralization. We evaluated the effects of Postn overexpression and RNAi-mediated suppression in mouse dental papilla cells (MDPs) on the expression of odontoblastic markers and Notch signaling molecules, and on the formation of mineralized nodules. Localization of Postn in the dental pulp tissue of normal and cavity-prepared molars was observed immunohistologically. Enforced overexpression of Postn in MDPs induced down-regulation of odontoblastic markers and in vitro mineralization. Conversely, silencing of Postn mRNA in MDPs induced up-regulation of odontoblastic markers and ALP activity. Up- and down-regulation of Postn caused increased and decreased expression, respectively, of Notch signaling molecules. Postn expression was minimal in normal dental pulp, but was rapidly and globally increased in the whole pulp tissue of molar teeth at 1 day after cavity preparation, decreasing thereafter. These results indicate that Postn may be a negative regulator of odontoblast differentiation/mineralization, and that may exert its actions via Notch signals.
authors.affiliation: Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
authors.forename: Mengu
authors.initials: M
authors.lastname: Zhou
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawashima
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Suzuk
authors.forename: Mioko
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Kayoko
authors.initials: K
authors.lastname: Ohnishi
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Katsube
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Tanabe
authors.forename: Akira
authors.initials: A
authors.lastname: Kudo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Saito
authors.forename: Hideaki
authors.initials: H
authors.lastname: Suda
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D003782:Dental Pulp / Q000166:cytology*; D015536:Down-Regulation; D007124:Immunoenzyme Techniques; D008297:Male; D008813:Mice, Inbred ICR; D009804:Odontoblasts / Q000166:cytology; D051880:Receptors, Notch / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014074:Tooth Calcification / Q000502:physiology*
chemical_list: D015815:Cell Adhesion Molecules; C082838:Postn protein, mouse; D051880:Receptors, Notch; D000469:Alkaline Phosphatase