title: Altered expression balance of matrix metalloproteinases and their inhibitors in human carotid plaque disruption: results of quantitative tissue analysis using real-time RT-PCR method.
abstract: BACKGROUND
  The balance between degradation and synthesis of extracellular matrix determines its content in atherosclerotic tissue. To examine the role of expression balance of matrix metalloproteinases (MMPs) to their inhibitors, tissue inhibitors of metalloproteinases (TIMPs) and tissue factor pathway inhibitor-2 (TFPI-2) in the development and disruption of atherosclerotic plaque, these gene expressions in human carotid plaque were quantitatively determined by real-time reverse transcription (RT)-polymerase chain reaction (PCR) method.
  
  
  METHODS
  Total RNA for cDNA synthesis was extracted from tissues in 24 patients with carotid endarterectomy. The amounts of cDNAs for MMP-1, -2, -3 and -9, TFPI-2 and TIMP-1, -2 and -3 were determined by real-time RT-PCR method, and normalized with glutaraldehyde 3-dehydrogenase.
  
  
  RESULTS
  In plaques, the expression MMP-1 (1.53+/-0.25, mean+/-S.E.M.), MMP-3 (1.99+/-0.59) and MMP-9 (2.00+/-0.51) was augmented compared to those in the adjacent control regions (0.60+/-0.16, 0.46+/-0.18 and 0.58+/-0.21, respectively, p<0.05). The expression of TFPI-2 was lower in plaques (0.32+/-0.08) than in controls (0.94+/-0.23, p<0.01). Although the expression of TIMP-1 was higher in plaques (1.28+/-0.23) than in controls (0.81+/-0.10, p<0.05), the indices of MMP-1/TIMP-1, MMP-3/TIMP-3 and MMP-9/TIMP-1 were still significantly higher in plaques. Interestingly, MMP-9 and the resulting MMP-9/TIMP-1 balance in plaques with disruption were significantly higher (3.36+/-1.52 and 1.66+/-0.12, n=11) than those in non-disrupted plaques (1.11+/-0.52 and 0.76+/-0.12, n=13, p<0.05).
  
  
  CONCLUSIONS
  With the decreased expression of TFPI-2, upregulation of MMPs in atherosclerotic plaque was disproportional to that of TIMPs, suggesting that imbalanced degradation and synthesis of extracellular matrix persists in advanced lesions, particularly in plaques with disruption.
authors.affiliation: Division of Cardiovascular Medicine and Bioscience, National Cardiovascular Center and Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Higashikata
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamagishi
authors.forename: Toshio
authors.initials: T
authors.lastname: Higashi
authors.forename: Izumi
authors.initials: I
authors.lastname: Nagata
authors.forename: Koji
authors.initials: K
authors.lastname: Iihara
authors.forename: Susumu
authors.initials: S
authors.lastname: Miyamoto
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.forename: Noritoshi
authors.initials: N
authors.lastname: Nagaya
authors.forename: Takashi
authors.initials: T
authors.lastname: Iwase
authors.forename: Hitonobu
authors.initials: H
authors.lastname: Tomoike
authors.forename: Aiji
authors.initials: A
authors.lastname: Sakamoto
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000378:metabolism*; D002340:Carotid Artery Diseases / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D016894:Endarterectomy, Carotid; D015870:Gene Expression; D005819:Genetic Markers; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D020782:Matrix Metalloproteinases / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012720:Severity of Illness Index; D019714:Tissue Inhibitor of Metalloproteinases / Q000235:genetics* / Q000378:metabolism
chemical_list: D005819:Genetic Markers; D012333:RNA, Messenger; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases