title: Matrix metalloproteinase (MMP-2, -9) and tissue inhibitor (TIMP-1, -2) activity in tear samples of pediatric type 1 diabetic patients: MMPs in tear samples from type 1 diabetes.
abstract: BACKGROUND
  The presence of matrix metalloproteinase (MMP-2, -9) and tissue inhibitor (TIMP-1, -2) activity in tear samples of pediatric type 1 diabetes mellitus (DM) patients and potential correlations with clinical parameters (Schirmer testing, glycosylated hemoglobin-HB(A1C)) were investigated.
  
  
  METHODS
  Tear samples from the right eyes of 27 type 1 DM patients and 17 healthy control subjects were included in this study. The MMP gelatinolytic activity was determined by gelatin zymography analysis using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), while MMP and TIMP concentrations (in ng/ml) were quantified in tears of type 1 diabetic patients and healthy controls, with the use of enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  MMP-9, TIMP-1, -2 levels, MMP-9/TIMP-1, and MMP-9/TIMP-2 ratios in the patient group were significantly elevated. There was a significant correlation between TIMP-2 and HB(A1C) values, as well as between MMP-2 and MMP-9.
  
  
  CONCLUSIONS
  Significant correlations between TIMP-2 and HB(A1C) and between Schirmer test results and HB(A1C) were revealed. Significant increase in tear MMP and TIMP levels in pediatric type 1 diabetic patients may be suggestive of disease progression and localized pathologic remodelling. Further studies are required in order to ascertain whether MMPs and TIMPs could be employed as indicators of early disease progression.
authors.affiliation: 2nd Department of Ophthalmology, School of Medicine, Papageorgiou General Hospital, Aristotle University of Thessaloniki, Papageorgiou General Hospital, Thessaloniki Ring Road, Thessaloniki, 564 03 Macedonia, Greece. chrys@med.auth.gr
authors.forename: Chrysanthos
authors.initials: C
authors.lastname: Symeonidis
authors.forename: Eleni
authors.initials: E
authors.lastname: Papakonstantinou
authors.forename: Asimina
authors.initials: A
authors.lastname: Galli
authors.forename: Ioannis
authors.initials: I
authors.lastname: Tsinopoulos
authors.forename: Asimina
authors.initials: A
authors.lastname: Mataftsi
authors.forename: Spyridon
authors.initials: S
authors.lastname: Batzios
authors.forename: Stavros A
authors.initials: SA
authors.lastname: Dimitrakos
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D013666:Tears / Q000201:enzymology*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; C560822:TIMP1 protein, human; C560823:TIMP2 protein, human; C517652:hemoglobin A1c protein, human; C522361:MMP2 protein, human; C579270:MMP9 protein, human