Expression of matrix metalloproteinases in patients with acute myocardial infarction

This study investigated the clinical significance of matrix metalloproteina ses (MMPs) in acute myocardial infarction (AMI) and the involvement of peri pheral blood mononuclear cells (PBMCs), which are a possible source of MMPs in AMI. Forty patients with AMI were recruited. Plasma and PBMCs were isol ated from peripheral blood on days 1, 7, 14 and 21 after the onset of AMI. Levels of MMP-1 and MMP-2 were measured by enzyme-linked immunosorbent assa y. The MMP-1 level in the culture medium of PBMCs after incubation for 24h was designated as 'PBMC-MMP-1 level.' Plasma MMP-1 did not significantly ch ange during the course of AMI, but the plasma MMP-2 levels increased gradua lly after the onset of AMI with maximum elevation on day 21 after onset. Pl asma MMP-2 activity also became significantly elevated during the course of AMI. PBMC-MMP-1 levels in the patients were significantly higher than thos e in control subjects over the course of AMI. Significant positive correlat ions were observed between maximum PBMC-MMP-1 levels and maximum plasma C-r eactive protein levels (r=+0.55, p<0.01) and left ventricular end-diastolic volume index (r=+0.63, p<0.001). In conclusion, plasma MMP-2 levels and ac tivity and MMP-1 production by PBMCs are increased in patients with AMI. In flammation after AMI may enhance production of MMP-1 by PBMCs. These change s may play an important role in the ventricular remodeling that occurs afte r AMI by promoting the degradation of the extracellular matrix.