Association of blood active matrix metalloproteinase-3 with carotid plaque score from a community population in Taiwan

Objective: Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of atherosclerosis. However, the relationship between blood levels of MMPs and the extent of carotid atherosclerosis remains uncertain. We assessed blood levels of active MMPs in relation to the extent of carotid plaque formation and intima-media thickness (IMT) in a community population in Taiwan. Methods: In 433 subjects from a community primary stroke prevention program, blood levels of active MMP-1, total and active MMP-3 and active MMP-9 were determined using enzyme-linked immunosorbent assays, carotid plaque score (PS) and IMT by high-resolution B-mode ultrasonography and the common MMP-1, MMP-3, and MMP-9 promoter low- and high-activity genotypes by polymerase chain reaction and restriction fragment length polymorphism. Results: Study subjects were separated into 3 groups based on PS: group 1 (PS. = 0), group 2 (PS. = 1-2) and group 3 (PS ≥ 3). Blood levels of active and total MMP-3 bear a highly significant relationship with PS (both p<0.0001). A multiple ordinal logistic regression analysis revealed that blood levels of active MMP-3 are correlated with PS (OR, 1.4; 95% CI, 1.1-1.8; p= 0.0038) but not IMT. MMP-3-1612 6A6A is a dominant genotype in this population, which is associated with higher levels of blood active MMP-3. Conclusion: Blood levels of active MMP-3 are associated with the extent of carotid atherosclerosis based on PS but not IMT in this community population in Taiwan and the MMP-3-1612 6A6A genotype is associated with higher levels of blood active MMP-3.