title: Ultrasound stimulation induces PGE(2) synthesis promoting cementoblastic differentiation through EP2/EP4 receptor pathway.
abstract: The present study aims to provide insights into how ultrasound treatment (US) can affect the regenerative response of cementum by evaluating the role of prostaglandin E(2) induced by ultrasound stimulation on cementoblastic differentiation. The mouse cementoblast cell line OCCM-30 was exposed to low-intensity ultrasound and the cyclooxygenase-2 (COX-2) mRNA expression and prostaglandin E(2) (PGE(2)) production were quantified. The role of the US-induced PGE(2) in mineralization was examined using COX-2 inhibitor and prostaglandin receptors (EP-receptors) agonists and antagonists. In addition, gene expression of differentiation markers related to mineral metabolism was evaluated. Ultrasound significantly enhanced COX-2 mRNA expression and PGE(2) production. PGE(2) induced by US mediated mineral nodule formation, whereas COX-2 inhibitor treatment eliminated the enhancement of mineralization induced by US stimulation. Mineral deposition was also inhibited by treatment with EP2 or EP4 antagonist. Moreover, up-regulation of differentiation markers induced by US was suppressed by treatment with COX-2 inhibitor. The present findings provide evidence that US stimulation has a positive effect on mineralization ability of cementoblasts through the activation of EP2/EP4 pathway, suggesting that US can be a promising therapeutic tool for cementum repair.
authors.affiliation: Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan. emanuelbraga@hiroshima-u.ac.jp
authors.forename: Emanuel Braga
authors.initials: EB
authors.lastname: Rego
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Inubushi
authors.forename: Aki
authors.initials: A
authors.lastname: Kawazoe
authors.forename: Kotaro
authors.initials: K
authors.lastname: Tanimoto
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Miyauchi
authors.forename: Eiji
authors.initials: E
authors.lastname: Tanaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Takata
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanne
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D003739:Dental Cementum / Q000166:cytology* / Q000000981:diagnostic imaging; D015232:Dinoprostone / Q000378:metabolism*; D051379:Mice; D018078:Receptors, Prostaglandin E / Q000378:metabolism*; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D015398:Signal Transduction / Q000502:physiology; D014465:Ultrasonics; D014463:Ultrasonography
chemical_list: C545645:Ptger2 protein, mouse; C545651:Ptger4 protein, mouse; D018078:Receptors, Prostaglandin E; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D015232:Dinoprostone