Quantitation and localization of matrix metalloproteinases and their inhibitors in human carotid endarterectomy tissues.

BACKGROUND: Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) play a central role in arterial wall remodeling, affecting stability of fibrous caps covering atherosclerotic plaques. The objective of this study was to determine the spatial distribution of TIMP mass and MMP mass and activity of carotid endarterectomy (CEA) tissues and relate it to the distribution of atherosclerotic lesions. METHODS AND RESULTS: Fresh CEA tissues were imaged by multicontrast MRI to generate 3D reconstructions. Tissue segments were cut transversely from the common, bifurcation, internal, and external regions. Segments were subjected to total protein extractions and analyzed by ELISA for MMP-2 and -9 and TIMP-1 and -2 mass and by zymography for gelatinase activity. Segments at or near the bifurcation with highly calcified lesions contained higher MMP levels and activity than segments distant from the bifurcation; highly fibrotic or necrotic plaque contained lower MMP levels and activity and higher TIMP levels. Fatty streak, fibroatheroma with hemorrhage and calcification, and fully occluded lesions were enriched in MMP-2, MMP-9, and TIMP-1 and TIMP-2, respectively. CONCLUSIONS: The spatial distribution of MMPs and TIMPs in carotid atherosclerotic lesions is highly heterogeneous, reflecting lesion location, size, and composition. This study provides the first semi-quantitative maps of differential distribution of MMPs and TIMPs over atherosclerotic plaques.

Transfer of antisense oligodeoxynucleotides against endothelin receptors A and B into human coronary smooth muscle cells and endothelial cells by apolipoprotein E peptide: an in vitro study.

Antisense oligodeoxynucleotides (AS-ODNs) are a new generation of therapeutic agents for gene therapy. To develop a new approach in regulating the expression of endothelin (ET) receptor, N,N-dipalmitylglycyl-apolipoprotein E (129-169) peptide (dpGapoE), an efficient gene delivery system, was used to transfect phosphorothioated AS-ODNs against nucleotides of human ET type A (ETA) receptors in human coronary smooth muscle cells (HCSMCs) and type B (ETB) receptors in human coronary endothelial cells (HCECs). After transfection, translocation to the nuclei and concentration in nuclear structures were observed in approximately 40% of HCSMCs and 60% of HCECs, respectively, at 48 h by fluorescence microscopy. Both the cellular ETA mRNA concentration in HCSMCs and ETB mRNA concentration in HCECs significantly declined. This approach may enable gene regulation in vivo and could be used to regulate vascular tone and constriction through ET receptors.