Proteoglycans in primate arteries. I. Ultrastructural localization and distribution in the intima.

Proteoglycans were identified and localized histochemically and ultrastructurally in normal and hyperplastic arterial intimas in nonhuman primates (Macaca nemestrina). These regions were consistently more alcianophilic than the adjacent medial layers and this alcianophilia was absent after treatment with glycosaminoglycan-degradative enzymes. Ultrastructurally, the intimal intercellular matrix consisted of numerous, irregularly shaped, 200-500-A diameter granules possessing 30--60-A diameter filamentous projections, and these granules were dispersed between collagen and elastic fibers. The granules exhibited a marked affinity for ruthenium red and were interconnected via their filamentous projections. The ruthenium red-positive granules were intimately associated with the plasma membrane of intimal smooth muscle cells and attached to collagen fibrils and elastic fibers. The matrix granules were completely removed after testicular hyaluronidase or chondroitinase ABC digestion but only partially removed after leech hyaluronidase treatment. These results suggest that the matrix granules contain some hyaluronic acid and one or more isomers of chondroitin sulfate. In addition to the large ruthenium red-positive matrix granules, a smaller class of ruthenium red-positive granule (100--200-A diameter) was present within the basement membranes beneath the endothelium and surrounding the smooth muscle cells. Ruthenium red also exhibited an affinity for the surface coat of the smooth muscle cells. The potential importance of proteoglycans in arterial intimal hyperplasia is discussed.

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EXPERIMENTAL ARTERIOSCLEROSIS

Journal of Experimental Medicine ◽

10.1084/jem.136.4.769 ◽

1972 ◽

Vol 136 (4) ◽

pp. 769-789 ◽

Cited By ~ 234

Author(s):

Michael B. Stemerman ◽

Russell Ross

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Balloon Catheter ◽

Muscle Cells ◽

Endothelial Injury ◽

Macaca Nemestrina ◽

Elastic Fibers ◽

Internal Elastic Lamina ◽

Principal Factors ◽

Elastic Lamina

Arteriosclerotic lesions have been produced in monkeys (Macaca nemestrina) by selective removal of the vascular endothelium with an intra-arterial balloon catheter. Immediately after de-endothelialization a platelet layer covers the denuded area. This thrombus is gradually removed and by 7 days the vessel appears to be largely reendothelialized. Beginning at day 4, smooth muscle cells undergo modification and migrate through fenestrae in the internal elastic lamina into the intima where they proliferate. By 28 days, the intimal lesion consists of multiple layers of smooth muscle cells surrounded by collagen and elastic fibers and basement-like material. After 3 months the lesions are markedly hyperplastic and contain new extracellular connective tissue elements. In contrast, with no further injury after 6 months the lesion has decreased markedly in size suggesting that it may be reversible in the absence of continued endothelial injury. The importance of endothelial "injury" exposing medial smooth muscle to plasma constituents may be the principal factors associated with the migration and proliferation of the smooth muscle cells into the intima resulting in the lesion. The smooth muscle cells do not contain lipid. The similarities of this lesion to the fibromusculo-elastic lesion or preatherosclerotic intimal hyperplasia in man makes it a useful model for the further study of atherosclerosis.

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Immunogold localization of HMB-45 antigen in pulmonary lymphangiomyomatosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141366 ◽

1995 ◽

Vol 53 ◽

pp. 998-999

Author(s):

J.M. Minda ◽

E. Dessy ◽

G. G. Pietra

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Room Temperature ◽

Osmium Tetroxide ◽

Muscle Cells ◽

Ultrastructural Localization ◽

Reproductive Age ◽

Thin Sections ◽

Smooth Muscle Proliferation ◽

Hmb 45

Pulmonary lymphangiomyomatosis (PLAM) is a rare disease occurring exclusively in women of reproductive age. It involves the lungs, lymph nodes and lymphatic ducts. In the lungs, it is characterized by the proliferation of smooth muscle cells around lymphatics in the bronchovascular bundles, lobular septa and pleura The nature of smooth muscle proliferation in PLAM is still unclear. Recently, reactivity of the smooth muscle cells for HMB-45, a melanoma-related antigen has been reported by immunohistochemistry. The purpose of this study was the ultrastructural localization of HMB-45 immunoreactivity in these cells using gold-labeled antibodies.Lung tissue from three cases of PLAM, referred to our Institution for lung transplantation, was embedded in either Poly/Bed 812 post-fixed in 1% osmium tetroxide, or in LR White, without osmication. For the immunogold technique, thin sections were placed on Nickel grids and incubated with affinity purified, monoclonal anti-melanoma antibody HMB-45 (1:1) (Enzo Diag. Co) overnight at 4°C. After extensive washing with PBS, grids were treated with Goat-anti-mouse-IgG-Gold (5nm) (1:10) (Amersham Life Sci) for 1 hour, at room temperature.

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Ascorbic Acid Increases the Thrombogenicity of Cellular Matrices

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646447 ◽

1991 ◽

Vol 66 (04) ◽

pp. 505-509 ◽

Cited By ~ 4

Author(s):

Georg A Hindriks ◽

Jan J Sixma ◽

Philip G de Groot

Keyword(s):

Extracellular Matrix ◽

Endothelial Cells ◽

Smooth Muscle ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Strong Increase ◽

Aggregate Formation ◽

Lower Shear ◽

The Matrix ◽

Proline Incorporation

SummaryWe have studied the influence of ascorbate on extracellular matrix formation in cultured human endothelial cells, smooth muscle cells and fibroblasts and measured the influence of the changed composition of their isolated extracellular matrices on their affinity for platelets. When endothelial cells were grown for a week in the presence of ascorbate, no influence on proline incorporation in their extracellular matrix was found. In accordance, no influence on platelet adhesion or aggregate formation on these matrices was detected. When smooth muscle cells were cultured in the presence of ascorbate, a strong increase in the amount of collagen types I and III in the extracellular matrix was found. When these matrices were perfused with whole blood, a significant enhanced increase in aggregate formation was observed. No influence was seen on the total coverage of the matrix with platelets. When fibroblasts were grown in the presence of ascorbate, no significant increase in proline incorporation in their matrix was measured. However, an increased adhesion of platelets was seen to the matrices at lower shear rates. We conclude that ascorbate feeding has a significant effect on endogenous deposited matrices of smooth muscle cells and fibroblasts, and that the changed composition had profound effects on platelet interaction with these matrices.

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Changes in the components of extracellular matrix and in growth properties of cultured aortic smooth muscle cells upon ascorbate feeding.

The Journal of Cell Biology ◽

10.1083/jcb.92.2.462 ◽

1982 ◽

Vol 92 (2) ◽

pp. 462-470 ◽

Cited By ~ 48

Author(s):

E Schwartz ◽

R S Bienkowski ◽

B Coltoff-Schiller ◽

S Goldfischer ◽

O O Blumenfeld

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Smooth Muscle Cells ◽

Time Course ◽

Cultured Cells ◽

Growth Parameters ◽

Muscle Cells ◽

Cellular Protein ◽

Collagen Accumulation ◽

The Matrix

Culture conditions can modify the composition of the extracellular matrix of cultured calf aortas smooth muscle cells. In the absence of ascorbate the major components of the matrix are microfibrillar proteins; deposition of collagen occurs upon ascorbate supplementation and, with increased time of exposure of cells to ascorbate, collagen becomes the dominant protein of the extracellular matrix (greater than 80%). Collagen accumulation follows a sigmoidal time-course, suggesting that it is a cooperative phenomenon. Covalent crosslinks are not required for collagen accumulation in the matrix. Microfibrillar proteins and increased amounts of proteoglycans and fibronectin accumulate concurrently with collagen but elastin deposition was not observed either with or without ascorbate feeding. Addition of ascorbate leads to a general stimulation of incorporation of [14C]proline into cellular protein and to changes in cell growth parameters and morphology: cell-doubling time decreases from 62 to 47 h and plating efficiency increases approximately fourfold. We conclude that the composition of the extracellular matrix assembled by cultured cells is subject to experimental manipulation and that changes in endogenously deposited matrix may have significant effects on cellular functions.

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Atheromatosis of arterial intima

Clinical Medicine (Russian Journal) ◽

10.18821/0023-2149-2016-94-8-582-590 ◽

2016 ◽

Vol 94 (8) ◽

pp. 582-590

Author(s):

Vladimir N. Titov ◽

T. A. Rozhkova ◽

V. A. Amelyushkina

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Arterial Wall ◽

Proteolytic Enzymes ◽

Muscle Cells ◽

Acid Hydrolases ◽

The Matrix ◽

Arterial Intima ◽

Hydrolysis Of

Phylogenetically late arterial intima of the elastic type contains no proteins for the transfer of ligandless oxidized low density lipoproteins (LDLP) for sedentary macrophages adsorbed on the matrix. Phylogenetically early cells realize the extracellular digestive reaction by releasing proteolytic enzymes (metalloproteinases) into intimal matrix that hydrolize matrix proteoglycans, adsorbed ligandless LDLP, detritus, and complete lysosomal hydrolysis of the most hydrophobic polyenic cholesterol esters (poly-ECS). Smooth muscle cells migrate from the middle muscular layer of the arterial wall, change their contractile phenotype to secretory one, and synthesize in situ de novomatrix proteoglycans. The arterial wall has three layers (monolayer endothelium, intimal media (smooth muscle cells), and adventitia) only in elastic type arteries. It is desirable to elucidate functional differences between phylogenetically early sedentarymacrophages and monocytes-macrophages of later origin and understand whether theydepends on specific features of activity of scavenger eceptors, CD36 translocases, expression of acid hydrolases synthesis for poly-ECS or realization of the extracellular digestion reaction. We believe that formation of atheromatous masses takes place in the matrix of arterial intima rather than in lysosomes taking into account limited possibilities for monocytes-macrophages to realize endocytosis of ligandless LDLP from the matrix. Given that atheromatosis is a syndrome of deficit of essential polyenic fatty acids (PFA) in the cells, intimal atheromatosisshould be regarded only as partial utilization of excess PFA in the matrix of elastic type arteries. At later stages of phylogenesis, intima was formed from media smooth muscle cells.

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