title: Inhibition of gingipains and Porphyromonas gingivalis growth and biofilm formation by prenyl flavonoids.
abstract: OBJECTIVE
  Porphyromonas gingivalis is considered a major pathogen of chronic periodontitis, which also may be implicated with systemic diseases such as atherosclerosis. Secreted cysteine proteases, gingipains Rgp and Kgp, are essential for P. gingivalis virulence. Some polyphenols and flavonoids are known to inhibit gingipain activity and interfere with biofilm formation by P. gingivalis. Many bioactive compounds have been isolated from Epimedium species, but availability of these compounds on gingipains and P. gingivalis is still unclear. Therefore, the aim of this study was to evaluate natural products from medical plants to develop a new therapeutic agent against periodontal disease.
  
  
  METHODS
  Prenylated flavonoids were isolated from Epimedium species plant using column chromatographies. The inhibitory effect of the prenylated flavonoids against protease activity of gingipains were examined using purified gingipains and fluorogenic substrates. Anti-P. gingivalis activity was evaluated to analyze planktonic growth and biofilm formation in brain heart infusion medium in the presence of the prenylated flavonoids.
  
  
  RESULTS
  We isolated 17 prenylated flavonoids (Limonianin, Epimedokoreanin B, etc.) from Epimedium species. We found that some prenylated flavonoids inhibited gingipain activity in a non-competitive manner with Kivalues at μm order. The prenylated flavonoids also hindered growth and biofilm formation of P. gingivalis, in a manner independent of gingipain inhibition by the compounds.
  
  
  CONCLUSIONS
  The results indicated an inhibitory effect of the prenylated flavonoids against P. gingivalis and would provide useful information for future development of periodontitis treatment that suppresses gingipains, P. gingivalis growth and biofilm formation.
authors.affiliation: Department of Life Science, Shokei University, Kumamoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kariu
authors.affiliation: Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Nakao
authors.affiliation: Division of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Division of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nakashima
authors.affiliation: Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.|Department of Oral Immunology and Infectious Disease, University of Louisville, School of Dentistry, Louisville, KY, USA.
authors.forename: J
authors.initials: J
authors.lastname: Potempa
authors.affiliation: Department of Molecular Pathology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Imamura
mesh_terms: D018829:Adhesins, Bacterial / Q000187:drug effects*; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D003546:Cysteine Endopeptidases / Q000187:drug effects*; D034181:Epimedium / Q000378:metabolism; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D000080867:Gingipain Cysteine Endopeptidases; D016966:Porphyromonas gingivalis / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D054876:Prenylation
chemical_list: D018829:Adhesins, Bacterial; D005419:Flavonoids; D000080867:Gingipain Cysteine Endopeptidases; D003546:Cysteine Endopeptidases
keywords: Porphyromonas gingivalis growth; biofilm; gingipains; prenylated flavonoids