Different expression of MMPs/TIMP-1 in human atherosclerotic lesions. Relation to plaque features and vascular bed.
BACKGROUND
Proteolytic imbalance might determine arterial remodeling and plaque destabilization in atherosclerotic vessels. The aim of this study was to examine differences in the patterns of metalloproteinases (MMPs) and MMP inhibitor (TIMP-1) expression in advanced human atheromas, both in relation to the plaque features and the vascular bed involved.


RESULTS
Immunohistochemistry for MMP-1, -3, -9 and TIMP-1 as well as the collagen content were measured in vascular sections from patients undergoing peripheral revascularization (carotid n=11, femoral n=23) and aorto-coronary bypass surgery (mammary arteries n=20, as controls). Increased expression of all MMPs was detected in atherosclerotic as compared with control sections (P<0.01). Aneurysmal plaques showed a significant increase of MMP-1 and-3 and a reduction in total collagen (P<0.05) in relation to occlusive lesions. Calcification areas in atherosclerotic plaques were consistently associated with increased TIMP-1 expression (P<0.01). Finally, MMP-9 expression was higher in occlusive lesions from carotid than femoral arteries (P<0.01).


CONCLUSIONS
Aneurysm lesions expressed higher MMP-1 and-3 expression than occlusive plaques, and MMP-9 was mainly detected in carotid as compared with femoral arteries. TIMP-1 was associated with arterial calcification. These differences in the MMPs/TIMP-1 expression might determine the evolution of advanced atherosclerotic plaques and contribute to its vulnerability.
Orbe
J
J
Atherosclerosis Research Laboratory, Division of Cardiovascular Pathophysiology, School of Medicine, University of Navarra, C/Irunlarrea 1, 31008 Pamplona, Spain.
Fernandez
L
L
Rodríguez
J A
JA
Rábago
G
G
Belzunce
M
M
Monasterio
A
A
Roncal
C
C
Páramo
José A
JA
D000368:Aged; D000783:Aneurysm / Q000378:metabolism; D001158:Arteries / Q000378:metabolism* / Q000473:pathology; D001161:Arteriosclerosis / Q000378:metabolism* / Q000473:pathology; D002114:Calcinosis / Q000150:complications / Q000378:metabolism; D002339:Carotid Arteries / Q000378:metabolism / Q000473:pathology; D003094:Collagen / Q000032:analysis; D005263:Femoral Artery / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis*
D019715:Tissue Inhibitor of Metalloproteinase-1; D003094:Collagen; D020782:Matrix Metalloproteinases