title: Serum levels and polymorphisms of matrix metalloproteinases (MMPs) in carotid artery atherosclerosis: higher MMP-9 levels are associated with plaque vulnerability.
abstract: BACKGROUND
  Matrix metalloproteinases are involved in atherosclerosis and plaque vulnerability.
  
  
  OBJECTIVE
  To investigate serum levels and genetic polymorphisms of matrix metalloproteinases (MMPs) -1, -3 and -9 in patients submitted to carotid endarterectomy.
  
  
  METHODS
  Genetic polymorphisms were evaluated using polymerase chain reaction (PCR-RFLP); serum levels were measured using ELISA; histological sections were stained with Picrosirius Red to analyze the fibrous cap thickness, lipid core and collagen content and with hematoxylin--eosin to detect the presence of intraplaque hemorrhage.
  
  
  RESULTS
  MMP-9 serum levels were significantly higher in patients with a thinner fibrous cap (p = 0.033) or acute or recent intraplaque hemorrhage (p = 0.008) on histology, as well as in patients with previous stroke (p = 0.009) or peripheral vascular disease (p = 0.049). No consistent associations were observed between different MMP genotypes and fibrous cap thickness, lipid core, collagen content or intraplaque hemorrhage.
  
  
  CONCLUSIONS
  MMP-9 serum levels were consistently associated with markers of carotid atherosclerosis and lesion vulnerability, whereas specific MMP genotypes were not.
authors.affiliation: Cardiology Division, Hospital de Clínicas de Porto Alegre and the Post-Graduate Program in Cardiology and Cardiovascular Sciences, UFRGS , Porto Alegre , Brazil .
authors.forename: Daiane
authors.initials: D
authors.lastname: Silvello
authors.forename: Luciane Barreneche
authors.initials: LB
authors.lastname: Narvaes
authors.forename: Luciano Cabral
authors.initials: LC
authors.lastname: Albuquerque
authors.forename: Luiz Felipe
authors.initials: LF
authors.lastname: Forgiarini
authors.forename: Luise
authors.initials: L
authors.lastname: Meurer
authors.forename: Nidiane Carla
authors.initials: NC
authors.lastname: Martinelli
authors.forename: Michael Everton
authors.initials: ME
authors.lastname: Andrades
authors.forename: Nadine
authors.initials: N
authors.lastname: Clausell
authors.forename: Kátia Gonçalves
authors.initials: KG
authors.lastname: dos Santos
authors.forename: Luis Eduardo
authors.initials: LE
authors.lastname: Rohde
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology; D002340:Carotid Artery Diseases / Q000097:blood / Q000201:enzymology* / Q000235:genetics; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D006801:Humans; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000235:genetics; D019278:Matrix Metalloproteinase 3 / Q000235:genetics; D020780:Matrix Metalloproteinase 9 / Q000097:blood* / Q000235:genetics; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011859:Radiography
chemical_list: C511768:MMP3 protein, human; D019278:Matrix Metalloproteinase 3; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9; C522360:MMP1 protein, human; D020781:Matrix Metalloproteinase 1