title: Expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in healthy and diseased human gingiva.
abstract: BACKGROUND
  The purpose of this study was to quantify the amount of matrix metalloproteinases such as MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, and MMP-13 and tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 expressed by human gingival explants in culture media and the area fraction (AA%) of gingival collagen fibers according to the degree of inflammation, to investigate a possible correlation between these enzymes and collagen loss.
  
  
  METHODS
  Gingival tissue specimens from 6 healthy controls (group 1), 17 patients with mild gingival inflammation (group 2), 10 patients with moderate gingival inflammation (group 3), and 9 patients with severe gingival inflammation (group 4) were placed in organ culture for 3 days. The MMPs and TIMPs in the culture media were quantified using zymography, dot blotting, and Western blotting. Paraffin gingival sections were stained with sirius red F3Ba for visualization of collagen fibers, then the area fraction (AA%) occupied by the gingival fibers was determined by automated image analysis.
  
  
  RESULTS
  The AA% occupied by collagen fibers significantly decreased from group 1 (53%) to group 4 (35%). The decrease in collagen fibers was inversely correlated with the significant increase in MMP-1, MMP-9, and MMP-13 (dot blotting analysis), with the increase of the active form of MMP-2, and with the active form and proform of MMP-9 (zymography analysis).
  
  
  CONCLUSIONS
  The present study showed that metalloproteinases, particularly MMP-2, MMP-9, MMP-1, and MMP-13, are involved in the gingival extracellular matrix degradation during periodontitis.
authors.affiliation: Department of Non-Mineralized Tissue Physiopathology, Faculty of Dental Surgery, Université René Descartes Paris V, Montrouge, France. godeau g@yahoo.fr
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Ejeil
authors.forename: Sylvie
authors.initials: S
authors.lastname: Igondjo-Tchen
authors.forename: Sabah
authors.initials: S
authors.lastname: Ghomrasseni
authors.forename: Bernard
authors.initials: B
authors.lastname: Pellat
authors.forename: Gaston
authors.initials: G
authors.lastname: Godeau
authors.forename: Bruno
authors.initials: B
authors.lastname: Gogly
mesh_terms: D015153:Blotting, Western; D016022:Case-Control Studies; D003470:Culture Media / Q000737:chemistry; D046508:Culture Techniques; D004591:Electrophoresis, Polyacrylamide Gel; D004792:Enzyme Precursors / Q000032:analysis; D005109:Extracellular Matrix / Q000201:enzymology; D024022:Fibrillar Collagens / Q000378:metabolism; D005881:Gingiva / Q000201:enzymology; D005891:Gingivitis / Q000201:enzymology*; D006801:Humans; D015151:Immunoblotting; D020782:Matrix Metalloproteinases / Q000032:analysis / Q000096:biosynthesis*; D010512:Periodontal Index; D010518:Periodontitis / Q000201:enzymology*; D019714:Tissue Inhibitor of Metalloproteinases / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D003470:Culture Media; D004792:Enzyme Precursors; D024022:Fibrillar Collagens; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases