title: Root canal content from primary endodontic infection and upregulation of gelatinases in fibroblast cells.
abstract: OBJECTIVE
  To investigate endotoxin levels from primary endodontic infections before and after chemomechanical preparation (CMP) and to determine their antigenicity against 3T3 fibroblasts through gelatinolytic activity of matrix metalloproteinases (MMPs).
  
  
  METHODS
  Twenty-four root canals with primary endodontic infection and apical periodontitis were selected. Samples were collected using paper points before (S1) and after chemomechanical preparation (CMP) (S2). The limulus amebocyte lysate assay was used for endotoxin measurement. Fibroblasts were stimulated with root canal contents for 24 h. Supernatants of cell cultures stimulated with root canal contents were collected after 24 h to determine the levels of MMP-2 and MMP-9 gelatinolytic activity using the zymography technique. Friedman and Wilcoxon tests were used to compare the amount of endotoxin before (S1) and after CMP (S2) (P < 0.05). Data obtained from gelatinolytic activity were analysed using anova and Tukey's tests (P < 0.05).
  
  
  RESULTS
  Endotoxin was recovered in 100% of the samples. There was a significant reduction in endotoxin levels after CMP (P < 0.05). A correlation was found between the levels of endotoxins and MMP-2 expression (P < 0.05). Root canal contents of initial samples (S1) induced significantly greater MMP-2 expression by fibroblasts when compared to S2 and the nonstimulated group (P < 0.05). No gelatinolytic activity of MMP-9 was observed in S1, S2 and control group.
  
  
  CONCLUSIONS
  Root canal contents from primary endodontic infections had gelatinolytic activity for MMP-2. Moreover, CMP was effective in reducing endotoxin levels and their antigenicity against fibroblasts on gelatinolytic activity.
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: D R
authors.initials: DR
authors.lastname: Herrera
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.|Health and Science Center, Grande Rio University (UNIGRANRIO), Rio de Janeiro, Brazil.
authors.forename: E J N L
authors.initials: EJ
authors.lastname: Silva
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: C C
authors.initials: CC
authors.lastname: Santos
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: A A
authors.initials: AA
authors.lastname: Zaia
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: C C R
authors.initials: CC
authors.lastname: Ferraz
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: J F A
authors.initials: JF
authors.lastname: Almeida
authors.affiliation: Department of Restorative Dentistry, Endodontics Division, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, Brazil.
authors.forename: B P F A
authors.initials: BP
authors.lastname: Gomes
mesh_terms: D018929:Cell Culture Techniques; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000378:metabolism* / Q000382:microbiology*; D004203:Disinfection / Q000379:methods; D004731:Endotoxins / Q000378:metabolism*; D005347:Fibroblasts / Q000201:enzymology*; D018093:Gelatinases / Q000378:metabolism*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D010485:Periapical Periodontitis / Q000378:metabolism* / Q000382:microbiology*; D018915:Root Canal Preparation / Q000379:methods*; D015854:Up-Regulation
chemical_list: D004731:Endotoxins; D018093:Gelatinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9
keywords: endotoxin; gelatinases; root canal infection