title: Myricetin blocks lipoteichoic acid-induced COX-2 expression in human gingival fibroblasts.
abstract: Periodontitis is an infectious disease caused by microorganisms present in dental bacterial plaque. Lipoteichoic acid (LTA) is a component of the external membrane of Gram-positive bacteria. It causes septic shock. Ingested flavonoids have been reported to directly affect the regulation of cyclooxygenase-2 (COX-2) expression induced by bacterial toxins. In this study, we examined the effects of four flavonoids (luteolin, fisetin, morin and myricetin) on the activation of ERK1/2, p38 and AKT, and on the synthesis of COX-2 in human gingival fibroblasts treated with LTA from Streptococcus sanguinis. We found that luteolin and myricetin blocked AKT and p38 activation and that myricetin blocked LTA-induced COX-2 expression. The results of our study are important for elucidating the mechanism of action of flavonoid regulation of inflammatory responses.
authors.affiliation: Laboratorio de Bioquímica, División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, Ciudad de México, México, gloria@fo.odonto.unam.mx.
authors.forename: Gloria
authors.initials: G
authors.lastname: Gutiérrez-Venegas
authors.forename: Oscar Alonso
authors.initials: OA
authors.lastname: Luna
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Arreguín-Cano
authors.forename: Cristina
authors.initials: C
authors.lastname: Hernández-Bermúdez
mesh_terms: D051546:Cyclooxygenase 2 / Q000096:biosynthesis* / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D005419:Flavonoids / Q000008:administration & dosage*; D005786:Gene Expression Regulation / Q000187:drug effects*; D005881:Gingiva / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013682:Teichoic Acids / Q000494:pharmacology
chemical_list: D005419:Flavonoids; D008070:Lipopolysaccharides; D016328:NF-kappa B; D013682:Teichoic Acids; C009900:lipoteichoic acid; C040015:myricetin; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D051057:Proto-Oncogene Proteins c-akt; D048052:Mitogen-Activated Protein Kinase 3