Expression of several matrix metalloproteinases (MMPs) in atherosclerotic plaques has been well documented, and there are findings to indicate that arterial inflammation is reflected in increased serum concentration of matrix metalloproteinase-9 (MMP-9). In coronary atherosclerosis, there is enhanced expression of this MMP, which may be predictive of the severity of the disease. We determined the concentrations of serum MMP-9 in 61 patients (47 males, 14 females) who had >50% obstruction in one or more coronary arteries as assessed by coronary angiography before bypass surgery. In a control group of 19 patients (9 males, 10 females) there were no pathological findings in coronary angiography. ANOVA showed that serum MMP-9 concentrations were highest in patients with 3-vessel coronary artery disease (CAD) (57.3+/-39.1 microg/L, p=0.011). The difference remained statistically significant after adjustment for age, diabetes and sex (p=0.025, ANCOVA). When the groups were compared with each other, serum MMP-9 concentration was higher in the patients with 3-vessel CAD than in those with 1- or 2-vessel CAD (40.4+/-25.1 microg/L, p=0.044) or in the controls (32.2+/- 16.1 microg/L, p=0.007). These results show that serum MMP-9 is elevated in patients with severe coronary stenosis compared with controls. Since MMP-9 has been suggested to reflect inflammation in atherosclerotic plaques, it may be useful in the evaluation of the severity of cardiovascular disease.

Our finding of elevated MMP-9 concentrations in sera of chronic alcohol abusers helps understand the mechanisms of cardiovascular risk among these subjects.

No abstract

Serum sialic acid does not appear to be an indicator of inflammation but is somehow connected with the level of total and HDL cholesterol. Serum matrix metalloproteinase-9 may provide a useful marker of inflammation because it correlates with the leukocyte count and is not associated with the lipid profile.

Elevated serum inflammatory markers have been reported in coronary heart disease. Levels of serum matrix metalloproteinase-9 (MMP-9), C-reactive protein (CRP), C3-complement (C3) and autoantibodies against oxidized low-density lipoprotein (oxLDL) in 120 male subjects with a history of myocardial infarction (MI) were compared with those in 250 age-matched controls, both groups from a large cross-sectional population survey, the FINRISK study. The concentrations of serum MMP-9 and autoantibodies against oxLDL were measured by enzyme-linked immunosorbent assay, CRP and C3 by immunonephelometry. MMP-9, CRP and C3 concentrations were higher in the subjects with a history of MI than in the controls (p=0.037, p=0.004, and p=0.006, respectively). There was no difference between the groups in serum levels of autoantibodies against oxLDL. In other background characteristics, men in the MI group had higher body mass index (BMI) and serum triglyceride values and lower serum HDL cholesterol values compared to controls (p=0.009, p=0.001, and p<0.001, respectively). When analyzed by stepwise multiple logistic regression using BMI, HDL cholesterol, triglycerides, CRP, C3 and MMP-9 as independent variables, the significant predictors for MI were HDL cholesterol (p=0.002) and MMP-9 (p=0.015). These results suggest that increased serum MMP-9 may reflect inflammatory pathologic processes that are related to progression of atherosclerosis.