Differences in Matrix Metalloproteinase-1 and Matrix Metalloproteinase-12 Transcript Levels Among Carotid Atherosclerotic Plaques With Different Histopathological Characteristics

Publisher Website
Google Scholar
Abstract
Background and Purpose— Previous studies have shown that atherosclerotic lesions express a number of matrix metalloproteinases (MMPs). Here we investigated whether transcript levels of MMP-1, -3, -7, -9, and -12 in carotid atherosclerotic plaques were correlated with histological features and clinical manifestations. Methods— Atherosclerotic plaques (n=50) removed from patients undergoing carotid endarterectomy were classified histologically using a system proposed by Virmani et al, and MMP-1, -3, -7, -9, and -12 transcript levels in these tissues were quantified by real-time reverse-transcriptase polymerase chain reaction. Results— Compared to plaques with a thick fibrous cap, those with a thin cap had a 7.8-fold higher MMP-1 transcript level ( P =0.006). MMP-3, -7, and -12 were 1.5-fold, 1.8-fold, and 2.1-fold, respectively, higher in thin cap plaques, but the differences did not reach statistical significance. MMP-12 transcript levels were significantly increased in ruptured plaques compared with lesions without cap disruption ( P =0.001). MMP-9 transcript levels were similar among the different types of lesion. MMP-1 and -12 transcript levels were significantly higher in plaques from patients with amaurosis fugax, than in those from asymptomatic patients ( P =0.029 and P =0.008 for MMP-1 and MMP-12, respectively), than in those from patients with stroke ( P =0.027 and P =0.001, respectively), and than in those from patients with transient ischemic attack ( P =0.046 and P =0.008, respectively). Conclusions— These data support a role of MMP-1 and -12 in determining atherosclerotic plaque stability.