title: Downregulation of lipopolysaccharide-induced intercellular adhesion molecule-1 expression via EP2/EP4 receptors by prostaglandin E2 in human fibroblasts.
abstract: In the present study, the effect of prostaglandin E2 (PGE2) on intercellular adhesion molecule-1 (ICAM-1) expression in human gingival fibroblasts (HGF) stimulated with lipopolysaccharides (LPS) was investigated. LPS were isolated from periodontopathic bacteria, Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) and Porphyromonas gingivalis (P. gingivalis), by the phenol-water method and Escherichia coli (E. coli) LPS was used as a control. PGE2 significantly inhibited A. actinomycetemcomitans-, P. gingivalis- and E. coli-LPS-induced ICAM-1 expression. Next, of four PGE2 receptor subtypes (EP1, EP2, EP3 and EP4), we examined which subtype(s) was involved in inhibition of LPS-elicited ICAM-1 expression by PGE2. Eleven-deoxy-PGE1, a selective EP2/EP4 agonist, and butaprost, a selective EP2 agonist, attenuated A. actinomycetemcomitans-, P. gingivalis- and E. coli-LPS-elicited ICAM-1 expression, although butaprost was less potent than PGE2 and 11-deoxy-PGE1. Sulprostone, an EP1/EP3 agonist, and ONO-AP-324, an EP3 agonist, was inert to the LPS-elicited ICAM-1 expression. Furthermore, dibutyryl cAMP, a cAMP analogue, and forskolin, an adenylate cyclase activator, downregulated A. actinomycetemcomitans-, P. gingivalis- and E. coli-LPS-elicited ICAM-1 expression in HGF. Our data suggest that PGE2 downregulates A. actinomycetemcomitans- and P. gingivalis-LPS-induced ICAM-1 expression in HGF, via EP2/EP4 receptors by cAMP-dependent signaling pathways. The cAMP-elevating agents such as EP2/EP4 receptor activators may serve to control inflammatory and immune responses in periodontal disease.
authors.affiliation: Department of Hard Tissue Engineering, Graduate School, Tokyo Medical and Dental University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Noguchi
authors.forename: K
authors.initials: K
authors.lastname: Iwasaki
authors.forename: M
authors.initials: M
authors.lastname: Shitashige
authors.forename: M
authors.initials: M
authors.lastname: Umeda
authors.forename: Y
authors.initials: Y
authors.lastname: Izumi
authors.forename: S
authors.initials: S
authors.lastname: Murota
authors.forename: I
authors.initials: I
authors.lastname: Ishikawa
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000472:pathogenicity; D002478:Cells, Cultured; D015232:Dinoprostone / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D004926:Escherichia coli / Q000472:pathogenicity; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D005881:Gingiva / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D010518:Periodontitis / Q000209:etiology; D016966:Porphyromonas gingivalis / Q000472:pathogenicity; D018078:Receptors, Prostaglandin E / Q000187:drug effects* / Q000378:metabolism*; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D015398:Signal Transduction
chemical_list: D008070:Lipopolysaccharides; C545644:PTGER2 protein, human; C545650:PTGER4 protein, human; D018078:Receptors, Prostaglandin E; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D018799:Intercellular Adhesion Molecule-1; D015232:Dinoprostone