title: Overexpression of MMP-9 and its inhibitors in blood mononuclear cells after myocardial infarction--is it associated with depressive symptomatology?
abstract: BACKGROUND
  Matrix metalloproteinase (MMP)-9 may play a central role in the development and progression of atherosclerosis. Emerging evidence also indicates an association between MMP-9 and depressive symptomatology. Here, we investigated whether expression of MMP-9 and its inhibitors in blood mononuclear cells and plasma were related to depressive symptoms in patients with a recent myocardial infarction (MI).
  
  
  RESULTS
  Blood sampling was performed between 6 and 18 months after MI in 57 patients. Forty-one clinically healthy subjects were included as controls. Gene expression of MMP-9 and its main tissue inhibitors TIMP-1 and -2 were analyzed in freshly isolated or cultured blood mononuclear cells. Corresponding protein levels were assessed in cell supernatants and plasma. In post-MI patients, mRNA levels of MMP-9 and TIMP-1 and -2 were significantly higher than in controls while protein levels in cell supernatants and plasma did not differ between groups. The Center for Epidemiological Studies - Depression (CES-D) scale was used to assess depressive symptomatology. Repeated assessments during the first 18 months after MI showed significantly higher CES-D scores in patients compared with controls. However, there were no relationships between depressive mood and any of the measurements of MMP-9 or TIMPs.
  
  
  CONCLUSIONS
  Our findings indicate that overexpression of MMP-9 and TIMPs in blood mononuclear cells and elevated depressive symptoms represent two unrelated phenomena after MI.
authors.affiliation: Department of Medical and Health Sciences, Division of Cardiovascular Medicine, Linköping University, Linköping, Sweden.
authors.forename: Simon
authors.initials: S
authors.lastname: Jönsson
authors.affiliation: Department of Medical and Health Sciences, Division of Cardiovascular Medicine, Linköping University, Linköping, Sweden.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Lundberg
authors.affiliation: Department of Medical and Health Sciences, Division of Cardiovascular Medicine, Linköping University, Linköping, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Jonasson
mesh_terms: D000368:Aged; D003863:Depression / Q000209:etiology / Q000378:metabolism* / Q000523:psychology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000378:metabolism* / Q000523:psychology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000235:genetics / Q000378:metabolism*
chemical_list: D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D020780:Matrix Metalloproteinase 9