title: Inhibition of host- and bacteria-derived proteinases by natural anthocyanins.
abstract: OBJECTIVE
  Host- and bacteria-derived proteinases are considered to play critical roles in periodontitis progression. This study investigated the ability of a blackcurrant extract and its major anthocyanins (cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside and delphinidin-3-O-rutinoside) to inhibit the activity of matrix metalloproteinases (MMPs), neutrophil elastase and periodontopathogen (Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola) proteinases.
  
  
  METHODS
  Enzyme inhibition was detected using fluorometric and colorimetric assays after incubating blackcurrant extract and its major anthocyanins (at concentrations of 6.25, 12.5, 25 and 50 μg/mL) with MMPs, elastase or bacterial proteinases, along with their specific substrates. Substrate degradation was recorded every hour for up to 4 h.
  
  
  RESULTS
  The blackcurrant extract (50 μg/mL) inhibited all proteinases tested. MMP-1 and MMP-9 were significantly inhibited by pure anthocyanins at concentrations ranging from 6.25 to 50 μg/mL. Elastase activity was inhibited by cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside in the range of 6.25-50 μg/mL and by delphinidin-3-O-rutinoside at 50 μg/mL. P. gingivalis, T. forsythia and T. denticola proteinases were also significantly inhibited by pure anthocyanins. In all cases, enzyme inhibition was time-dependent.
  
  
  CONCLUSIONS
  Our study showed that a blackcurrant extract and its major anthocyanins were able to inhibit the activity of host- and bacteria-derived proteinases. This suggests that such natural compounds may represent promising agents for use in adjunctive treatments for periodontitis.
authors.affiliation: Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, QC, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Santos
authors.forename: V D
authors.initials: VD
authors.lastname: La
authors.forename: C
authors.initials: C
authors.lastname: Bergeron
authors.forename: D
authors.initials: D
authors.lastname: Grenier
mesh_terms: D000872:Anthocyanins / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors; D001439:Bacteroides / Q000201:enzymology; D005960:Glucosides / Q000494:pharmacology; D006801:Humans; D019272:Leukocyte Elastase / Q000009:adverse effects; D020781:Matrix Metalloproteinase 1 / Q000009:adverse effects; D061965:Matrix Metalloproteinase Inhibitors; D010936:Plant Extracts / Q000494:pharmacology*; D016966:Porphyromonas gingivalis / Q000201:enzymology; D011480:Protease Inhibitors / Q000494:pharmacology*; D059748:Proteolysis; D031965:Ribes / Q000737:chemistry*; D048373:Treponema denticola / Q000201:enzymology
chemical_list: D000872:Anthocyanins; D001426:Bacterial Proteins; D005960:Glucosides; D061965:Matrix Metalloproteinase Inhibitors; D010936:Plant Extracts; D011480:Protease Inhibitors; C462279:cyanidin-3-O-beta-glucopyranoside; C010705:delphinidin-3-rutinoside; D019272:Leukocyte Elastase; D020781:Matrix Metalloproteinase 1; C428983:cyanidin 3-rutinoside