title: Cigarette smoke condensate affects the collagen-degrading ability of human gingival fibroblasts.
abstract: OBJECTIVE
  Cigarette smoke condensate, the particulate matter of cigarette smoke, is composed of thousands of chemicals, including nicotine. Cigarette smoking is a risk factor for periodontal disease. This study investigated the influence of cigarette smoke condensate on the collagen-degrading ability of human gingival fibroblasts and its mechanism.
  
  
  METHODS
  Human gingival fibroblasts were exposed for 72 h to various concentrations of total particulate matter cigarette smoke condensate. Cell proliferation and cytotoxicity were evaluated using water-soluble tetrazolium-1 and lactate dehydrogenase, respectively. The collagen-degrading ability of human gingival fibroblasts was evaluated in collagen-coated six-well plates. Conditioned media and membrane extracts were collected for zymography and western blot analyses of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs).
  
  
  RESULTS
  Cell proliferation decreased and cytotoxicity increased in human gingival fibroblasts with increasing concentrations of cigarette smoke condensate. Cell proliferation decreased by more than 50% (p < 0.05) when the concentrations of total particulate matter cigarette smoke condensate were above 200 microg/mL, and cytotoxicity increased to more than 30% (p < 0.05) when the concentrations of total particulate matter cigarette smoke condensate were above 400 microg/mL. Cigarette smoke condensate increased the collagen-degrading ability of human gingival fibroblasts, especially at a concentration of 100 microg/mL (1.5-fold increase, p < 0.05) compared with the control. Cigarette smoke condensate increased the production of proMMP-1, proMMP-2, MMP-14 and TIMP-1, and decreased the production of TIMP-2, in conditioned media. Furthermore, compared with the control group, cigarette smoke condensate increased the production of MMP-2, MMP-14 and TIMP-2 in membrane extracts, especially at concentrations of 50-100 microg/mL.
  
  
  CONCLUSIONS
  Cigarette smoke condensate affects human gingival fibroblast proliferation and is toxic at total particulate matter cigarette smoke condensate concentrations of >or= 400 microg/mL. Cigarette smoke condensate can increase the collagen-degrading ability of human gingival fibroblasts by altering the production and localization of MMPs and TIMPs.
authors.affiliation: Department of Oral Biology, Indiana University School of Dentistry, Indianapolis, IN 46202, USA.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.forename: F
authors.initials: F
authors.lastname: Song
authors.forename: L J
authors.initials: LJ
authors.lastname: Windsor
mesh_terms: D002448:Cell Adhesion; D016923:Cell Death; D049109:Cell Proliferation; D048430:Cell Shape; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism*; D017077:Culture Media, Conditioned; D004792:Enzyme Precursors / Q000032:analysis; D005347:Fibroblasts / Q000201:enzymology / Q000473:pathology*; D018093:Gelatinases / Q000032:analysis; D005881:Gingiva / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D007202:Indicators and Reagents; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D020781:Matrix Metalloproteinase 1 / Q000032:analysis; D053511:Matrix Metalloproteinase 14 / Q000032:analysis; D020778:Matrix Metalloproteinase 2 / Q000032:analysis; D020782:Matrix Metalloproteinases / Q000032:analysis; D008928:Mitochondria / Q000201:enzymology; D010088:Oxidoreductases / Q000032:analysis; D012906:Smoke / Q000009:adverse effects*; D013778:Tetrazolium Salts; D013997:Time Factors; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000032:analysis; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000032:analysis; D019714:Tissue Inhibitor of Metalloproteinases / Q000032:analysis; D014026:Nicotiana / Q000009:adverse effects*
chemical_list: D017077:Culture Media, Conditioned; D004792:Enzyme Precursors; D007202:Indicators and Reagents; D012906:Smoke; D013778:Tetrazolium Salts; D019715:Tissue Inhibitor of Metalloproteinase-1; D019714:Tissue Inhibitor of Metalloproteinases; D019716:Tissue Inhibitor of Metalloproteinase-2; D003094:Collagen; D010088:Oxidoreductases; D007770:L-Lactate Dehydrogenase; D018093:Gelatinases; D020782:Matrix Metalloproteinases; C069860:progelatinase; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D020781:Matrix Metalloproteinase 1; C507086:MMP14 protein, human; D053511:Matrix Metalloproteinase 14