title: Matrix metalloproteinase-9 concentration in the cerebral extracellular fluid of patients during the acute phase of aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  The pathogenesis of delayed cerebral ischemia (DCI) in aneurysmal subarachnoid hemorrhage (aSAH) is multi-factorial and not completely elucidated. Matrix metalloproteinase-9 (MMP-9) might participate in wall remodeling leading to luminal narrowing. The authors investigated  MMP-9 concentration in brain extracellular fluid of aSAH patients and assessed whether this enzyme could have a predictive value for the risk of DCI.
  
  
  METHODS
  Patients were classified according to the grading of the World Federation of Neurological Surgeons (WFNS) in low- and high-grade  patients (WFNS = 1-3, n = 9 and WFNS = 4-5, n = 12, respectively). Cerebral microdialysis probes were placed in brain parenchyma of the respective vascular territory of the aneurysm in 21 consecutive aSAH patients, enrolled  in a prospective study on inflammation. Microdialysis samples, collected daily from day 0 until day 8 after aSAH, were retrospectively analyzed for MMP-9 by zymography.
  
  
  RESULTS
  Initial concentration of the MMP-9 proform (pro-MMP-9) was significantly higher in high-grade patients  as compared to low-grade patients. Furthermore, initial pro-MMP-9 concentration in patients with DCI was seven-fold higher than in asymptomatic patients. Pro-MMP-9 values greater than or equal to 0·27 pg/μl showed 83% sensitivity and 63% specificity in predicting vasospasm. The mature  form of the MMP-9 could be preferentially detected in patients with DCI but was usually low.
  
  
  CONCLUSIONS
  The pro and mature forms of MMP-9 were released locally in the brain after aSAH. Pro-MMP-9 release was related to WFNS grade severity. This protease, considered as playing a critical  role in endothelial basal membrane damage, may contribute to the inflammatory processes leading to arterial narrowing.
authors.affiliation: Faculty of Medicine, University of Geneva, Switzerland. asita.sarrafzadeh@charite.de
authors.forename: Asita
authors.initials: A
authors.lastname: Sarrafzadeh
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Copin
authors.forename: Daniel Jiménez
authors.initials: DJ
authors.lastname: Bengualid
authors.forename: Natacha
authors.initials: N
authors.lastname: Turck
authors.forename: Peter
authors.initials: P
authors.lastname: Vajkoczy
authors.forename: Philippe
authors.initials: P
authors.lastname: Bijlenga
authors.forename: Karl
authors.initials: K
authors.lastname: Schaller
authors.forename: Yvan
authors.initials: Y
authors.lastname: Gasche
mesh_terms: D000328:Adult; D000368:Aged; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D045604:Extracellular Fluid / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D017551:Microdialysis; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000201:enzymology* / Q000473:pathology*; D014057:Tomography, X-Ray Computed
chemical_list: D020780:Matrix Metalloproteinase 9