Is the Phenotypic Change in Vascular Smooth Muscle Cells a Prerequisite for the Efficacy of Environmental Cues as Inducers of Arterial Wall Lesions?

1997 ◽  
Vol 34 (4) ◽  
pp. 321-323
Author(s):  
A. Bobik
1999 ◽  
Vol 82 (12) ◽  
pp. 1764-1767 ◽  
Author(s):  
Dean Cain ◽  
David Sane ◽  
Reidar Wallin

SummaryMatrix GLA protein (MGP) is an inhibitor of calcification in the arterial wall and its activity is dependent upon vitamin K-dependent γ-carboxylation. This modification is carried out by a warfarin sensitive enzyme system that converts specific Glu residues to γ-carboxyglutamic acid (GLA) residues. Recent studies have demonstrated that the γ-carboxylation system in the arterial wall, in contrast to that in the liver, is unable to use vitamin K as an antidote to warfarin.By use of immunohistochemistry we demonstrate that MGP is expressed in the arterial wall and immunocytochemistry localized the MGP precursors to the endoplasmic reticulum in vascular smooth muscle cells. Resting smooth vascular muscle cells in the aortic wall and proliferating cells from explants of the aorta have all the enzymes needed for γ-carboxylation of MGP. However, when compared to the liver system, expression of the enzymes of the γ-carboxylation system in vascular smooth muscle cells is different. Of particular interest is the finding that the specific activity of the warfarin sensitive enzyme vitamin K epoxide reductase is 3-fold higher in vascular smooth muscle cells than in liver. DT-diaphorase, which catalyses the antidotal pathway for vitamin K reduction in liver, is 100-fold less active in resting vascular smooth muscle cells than in liver. Data obtained from an in vitro γ-carboxylation system suggest that the antidotal pathway catalyzed by DT-diaphorase in the vessel wall is unable to provide the carboxylase with enough reduced vitamin K to trigger γ-carboxylation of MGP. This finding provides an explanation to the inability of vitamin K to work as an antidote to warfarin intoxication of the arterial wall. Therefore the vitamin K dependent γ-carboxylation system in the arterial wall share a common feature with the system in bone cells by being unable to utilize vitamin K as an antidote.


PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e116295 ◽  
Author(s):  
Kevin Guedj ◽  
Jamila Khallou-Laschet ◽  
Marc Clement ◽  
Marion Morvan ◽  
Sandrine Delbosc ◽  
...  

2006 ◽  
Vol 291 (1) ◽  
pp. C50-C58 ◽  
Author(s):  
Mei Han ◽  
Jin-Kun Wen ◽  
Bin Zheng ◽  
Yunhui Cheng ◽  
Chunxiang Zhang

Phenotypic change of vascular smooth muscle cells (VSMCs) from a differentiated to a dedifferentiated state accompanies the early stage of atherosclerosis and restenosis. Although much progress has been made in determining the molecular mechanisms involved in VSMC dedifferentiation, research on VSMC redifferentiation is hindered by the lack of an appropriate complete redifferentiation model. We established an in vitro model of redifferentiation by using postconfluent VSMCs from human umbilical artery. We demonstrated that serum-deprived VSMCs are capable of complete redifferentiation. After serum deprivation, postconfluent cultured human umbilical VSMCs became elongated and spindle shaped, with elevation of myofilament density, and reacquired contraction. Expressions of VSMC-specific contractile proteins, such as smooth muscle (SM) α-actin, SM-myosin heavy chain, calponin, and SM 22α, were increased and reached the levels in differentiated cells after serum deprivation. To determine the molecular mechanism of the phenotypic reversion, the levels of expression, phosphorylation, and binding activity of serum response factor (SRF), a key phenotypic modulator for VSMCs, were measured. The results showed that SRF binding activity with CArG motif was significantly increased after serum deprivation, whereas no changes were found in SRF expression and phosphorylation. The increased SRF binding activity was accompanied by an increase in expression of its coactivators such as myocardin. Furthermore, the phenotypic reversion was markedly inhibited by decoy double-strand oligodeoxynucleotides containing SM α-actin CArG motif, which was able to competitively bind to SRF. The results suggested that serum deprivation results in redifferentiation of human umbilical VSMCs. This novel model of VSMC phenotypic reversion should be valuable for research on vascular disease.


2005 ◽  
Vol 202 (5) ◽  
pp. 663-671 ◽  
Author(s):  
Sergey Filippov ◽  
Gerald C. Koenig ◽  
Tae-Hwa Chun ◽  
Kevin B. Hotary ◽  
Ichiro Ota ◽  
...  

During pathologic vessel remodeling, vascular smooth muscle cells (VSMCs) embedded within the collagen-rich matrix of the artery wall mobilize uncharacterized proteolytic systems to infiltrate the subendothelial space and generate neointimal lesions. Although the VSMC-derived serine proteinases, plasminogen activator and plasminogen, the cysteine proteinases, cathepsins L, S, and K, and the matrix metalloproteinases MMP-2 and MMP-9 have each been linked to pathologic matrix-remodeling states in vitro and in vivo, the role that these or other proteinases play in allowing VSMCs to negotiate the three-dimensional (3-D) cross-linked extracellular matrix of the arterial wall remains undefined. Herein, we demonstrate that VSMCs proteolytically remodel and invade collagenous barriers independently of plasmin, cathepsins L, S, or K, MMP-2, or MMP-9. Instead, we identify the membrane-anchored matrix metalloproteinase, MT1-MMP, as the key pericellular collagenolysin that controls the ability of VSMCs to degrade and infiltrate 3-D barriers of interstitial collagen, including the arterial wall. Furthermore, genetic deletion of the proteinase affords mice with a protected status against neointimal hyperplasia and lumen narrowing in vivo. These studies suggest that therapeutic interventions designed to target MT1-MMP could prove beneficial in a range of human vascular disease states associated with the destructive remodeling of the vessel wall extracellular matrix.


2019 ◽  
Vol 8 (1) ◽  
pp. 50-60
Author(s):  
Hozhabr Mozafari ◽  
Changchun Zhou ◽  
Linxia Gu

Abstract The stiffness of arterial wall in response to cardiovascular diseases has been associated with the changes in extracellular matrix (ECM) proteins, i.e., collagen and elastin. Vascular smooth muscle cells (VSMCs) helped to regulate the ECM reorganizations and thus contributed to arterial stiffness. This article reviewed experimental and computational studies for quantifying the roles of ECM proteins and VSMCs in mechanical properties of arteries, including nanostructure and mechanical properties of VSMCs and ECMs, cell-ECM interaction, and biomimetic gels/scaffolds induced contractile properties and phenotype changing of VSMCs. This work will facilitate our understanding of how the microenvironments and mechanotransduction impact and regulate the arterial adaptation.


1999 ◽  
Vol 145 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Melinda Fitzgerald ◽  
Ian P. Hayward ◽  
Anita C. Thomas ◽  
Gordon R Campbell ◽  
Julie H. Campbell

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