title: Sodium butyrate induces the production of cyclooxygenases and prostaglandin E₂ in ROS 17/2.8 osteoblastic cells.
abstract: OBJECTIVE
  Sodium butyrate (butyric acid; BA) is a major metabolic by-product of the anaerobic periodontopathic bacteria present in subgingival plaque. We examined the effects of BA and/or indomethacin on cell proliferation, the expression of cyclooxygenases (COXs), prostaglandin (PG) receptors (EP1-4), extracellular matrix proteins, such as type I collagen and osteopontin, and PGE(2) production, using ROS17/2.8 cells as osteoblasts.
  
  
  METHODS
  The rat clonal cell line ROS 17/2.8 was cultured with 0, 10(-5), 10(-4), and 10(-3)M BA in the presence or absence of 0.5 μM indomethacin, for up to 7 days. The expression of COX-1, COX-2, EP1, EP2, EP3, EP4, type I collagen, and osteopontin was examined at the mRNA and protein levels using real-time PCR and Western blotting, respectively. The amount of PGE(2) in the culture medium was measured by ELISA.
  
  
  RESULTS
  Proliferation of ROS 17/2.8 cells was not affected by the addition of BA. However, PGE(2) production and the expression of COX-1 and COX-2 increased with the addition of BA. In contrast, indomethacin, an inhibitor of COX, blocked the stimulatory effect of BA. Furthermore, EP2 expression increased with BA treatment, whereas EP1 expression was not affected and the expression of EP3 and EP4 was not detected. The addition of BA also increased the expression of type I collagen and osteopontin. Indomethacin blocked about 50% of the stimulatory effect of BA on type I collagen, whereas it did not block the effect on osteopontin.
  
  
  CONCLUSIONS
  These results suggest that BA induces PGE(2) production by increasing the expression of COX-1 and COX-2 in osteoblasts, and that an autocrine action of the produced PGE(2), via EP1 or BA-induced EP2, is related to an increase in type I collagen expression by BA.
authors.affiliation: Division of Oral Health Sciences, Nihon University Graduate School of Dentistry, Tokyo, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Iida
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kawato
authors.forename: Hideki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Natsuko
authors.initials: N
authors.lastname: Tanabe
authors.forename: Kumiko
authors.initials: K
authors.lastname: Nakai
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
authors.forename: Naoto
authors.initials: N
authors.lastname: Suzuki
authors.forename: Kuniyasu
authors.initials: K
authors.lastname: Ochiai
authors.forename: Masao
authors.initials: M
authors.lastname: Maeno
mesh_terms: D000818:Animals; D019898:Autocrine Communication / Q000187:drug effects; D015153:Blotting, Western; D002087:Butyrates / Q000494:pharmacology*; D018929:Cell Culture Techniques; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D024042:Collagen Type I / Q000187:drug effects; D051545:Cyclooxygenase 1 / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000187:drug effects; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D007213:Indomethacin / Q000494:pharmacology; D008565:Membrane Proteins / Q000187:drug effects; D010006:Osteoblasts / Q000187:drug effects* / Q000201:enzymology; D053495:Osteopontin / Q000187:drug effects; D016133:Polymerase Chain Reaction; D011451:Prostaglandin-Endoperoxide Synthases / Q000187:drug effects*; D051381:Rats; D058307:Receptors, Prostaglandin E, EP2 Subtype / Q000187:drug effects; D058308:Receptors, Prostaglandin E, EP3 Subtype / Q000187:drug effects; D058309:Receptors, Prostaglandin E, EP4 Subtype / Q000187:drug effects
chemical_list: D002087:Butyrates; D024042:Collagen Type I; D016861:Cyclooxygenase Inhibitors; D008565:Membrane Proteins; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058308:Receptors, Prostaglandin E, EP3 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D053495:Osteopontin; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; C496513:Ptgs1 protein, rat; C489691:Ptgs2 protein, rat; D015232:Dinoprostone; D007213:Indomethacin