OBJECTIVETo investigate serum level and gene polymorphisms of matrix metalloproteinase 9 (MMP-9), and platelet glycoprotein VI (GPVI) in patients with acute coronary syndrome (ACS).

METHODSIn a prospective study of 179 patients with documented ACS and 164 controls, we measured baseline serum MMP-9 levels using ELISA and determined the MMP-9/C-1562T and MMP-9/G5564A genotypes using PCR-restriction fragment length polymorphism. Fib serum level was measured by Clauss assay. We also analyzed the Fib/Bbeta-148C/T and GPVI/T13254C polymorphisms.

RESULTSSerum levels of MMP-9 and Fib in ACS patients were significantly higher than in controls (P < 0.001), and serum level of Fib in the acute myocardial infarction group was higher than in patients with unstable angina (P < 0.05). No significant difference between ACS patients and controls was found in frequencies of MMP-9/C-1562T, MMP-9/G5564A, Fib/Bbeta-148C/T, and GPVI/T13254C genotypes and alleles (P > 0.05). The T allele of the Fib/Bbeta-148T polymorphism was associated with increased plasma Fib level (P < 0.05). There was a strong positive correlation between serum level of MMP-9 and Fib (r = 0.289, P < 0.01).

CONCLUSIONSerum levels of MMP-9 and Fib were independent risk factors of ACS. There was an obvious relationship between the Bbeta-148C/T mutation and high Fib level. No significant difference between controls and ACS patients was found in the frequencies of MMP-9 C-1562T and G5564A, Fib Bbeta-148C/T and GPVI T13254C genotypes and alleles (P > 0.05).