title: Mechanical stress induces osteopontin via ATP/P2Y1 in periodontal cells.
abstract: Our previous study showed that mechanical stress induced the expression of osteopontin (OPN) in human periodontal ligament (HPDL) cells through the Rho kinase pathway. The increase of OPN expression via Rho kinase has been demonstrated to be triggered by nucleotide. Therefore, we hypothesized that nucleotides, particularly adenosine triphosphate (ATP), participated in the stress-induced OPN expression in HPDL cells. In the present study, the roles of ATP and P2Y1 purinoceptor were examined. Reverse-transcription polymerase chain-reaction and Western blot analysis revealed that the stress-induced ATP exerted its stimulatory effect on OPN expression. The inductive effect was attenuated by apyrase and completely inhibited by the Rho kinase inhibitor, as well as by the P2Y1 antagonist. We here propose that stress induces release of ATP, which in turn mediates Rho kinase activation through the P2Y1 receptor, resulting in the up-regulation of OPN. Stress-induced ATP could play a significant role in alveolar bone resorption.
authors.affiliation: Department of Anatomy, Graduate School of Oral Biology, Faculty of Dentistry, Chulalongkorn University, Pathumwan, Bangkok, Thailand.
authors.forename: S
authors.initials: S
authors.lastname: Wongkhantee
authors.forename: T
authors.initials: T
authors.lastname: Yongchaitrakul
authors.forename: P
authors.initials: P
authors.lastname: Pavasant
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D016301:Alveolar Bone Loss / Q000378:metabolism; D015153:Blotting, Western; D002478:Cells, Cultured; D006801:Humans; D053495:Osteopontin / Q000096:biosynthesis*; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058472:Receptors, Purinergic P2Y1; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013314:Stress, Mechanical; D015854:Up-Regulation; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: C546382:P2RY1 protein, human; D018048:Receptors, Purinergic P2; D058472:Receptors, Purinergic P2Y1; D053495:Osteopontin; D000255:Adenosine Triphosphate; D054460:rho-Associated Kinases