scholarly journals Rho Kinase Regulates Aortic Vascular Smooth Muscle Cell Stiffness Via Actin/SRF/Myocardin in Hypertension

2017 ◽  
Vol 44 (2) ◽  
pp. 701-715 ◽  
Author(s):  
Ning Zhou ◽  
Jia-Jye Lee ◽  
Shaunrick Stoll ◽  
Ben Ma ◽  
Kevin D. Costa ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Blood Pressure ◽  
Smooth Muscle ◽  
Smooth Muscle Cell ◽  
Aortic Stiffness ◽  
Rho Kinase ◽  
Specific Inhibitor ◽  
Wky Rats ◽  
Aortic Stiffening

Background/Aims: Our previous studies demonstrated that intrinsic aortic smooth muscle cell (VSMC) stiffening plays a pivotal role in aortic stiffening in aging and hypertension. However, the underlying molecular mechanisms remain largely unknown. We here hypothesized that Rho kinase (ROCK) acts as a novel mediator that regulates intrinsic VSMC mechanical properties through the serum response factor (SRF) /myocardin pathway and consequently regulates aortic stiffness and blood pressure in hypertension. Methods: Four-month old male spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were studied. Aortic stiffness was measured by echography. Intrinsic mechanical properties of VSMCs were measured by atomic force microscopy (AFM) in vitro. Results: Compared to WKY rats, SHR showed a significant increase in aortic stiffness and blood pressure, which is accompanied by a remarkable cell stiffening and ROCK activation in thoracic aortic (TA) VSMCs. Theses alterations in SHR were abolished by Y-27632, a specific inhibitor of ROCK. Additionally, boosted filamentous/globular actin ratio was detected in TA VSMCs from SHR versus WKY rats, resulting in an up-regulation of SRF and myocardin expression and its downstream stiffness-associated genes including α-smooth muscle actin, SM22, smoothelin and myosin heavy chain 11. Reciprocally, these alterations in SHR TA VSMCs were also suppressed by Y-27632. Furthermore, a specific inhibitor of SRF/myocardin, CCG-100602, showed a similar effect to Y-27632 in SHR in both TA VSMCs stiffness in vitro and aorta wall stiffness in vivo. Conclusion: ROCK is a novel mediator modulating aortic VSMC stiffness through SRF/myocardin signaling which offers a therapeutic target to reduce aortic stiffening in hypertension.

Abstract 188: I X2 X2

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Ning Zhou ◽  
Shaunrick Stoll ◽  
Hongyu Qiu
Keyword(s):  
Smooth Muscle ◽  
Aortic Stiffness ◽  
Nuclear Translocation ◽  
Specific Inhibitor ◽  
Fold Increase ◽  
Aortic Pressure ◽  
Doppler Imaging ◽  
Stiffness Index ◽  
Wky Rats ◽  
Gene And Protein Expression

Background: An increase in aortic stiffness is a fundamental component of hypertension. However, the molecular mechanism involved is unclear. Our hypothesis is that the increased aortic stiffness in hypertension is partially due to the activation of serum response factor (SRF) /myocardin in vascular smooth muscle cells (VSMCs). Methods: 4 months old male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied. Aortic pressure and stiffness were measured by a Millar catheter and by Doppler imaging echocardiography, respectively. VSMCs were isolated from thoracic aorta (TA), then cultured and tested at passages 2 to 4. Real time PCR and western blot were used to detect the gene and protein expression. Results: Aortic pressure was higher in SHR than WKY (mean arterial pressure (MAP) 138.7±11.8 vs 102.7±7 mmHg, p <0.01). Aorta stiffness reflected by arterial stiffness index (ASI) was 2.5-fold higher in SHR vs WKY ( p <0.01). Compared to WKY, VSMCs from SHR TA showed a 12-fold increase in SRF, a nuclear transcriptional factor, and 2.7-fold increase in myocardin, a smooth muscle specific coactivator of SRF, at both mRNA and protein levels (All, p <0.01 vs. WKY TA VSMCs). Myocardin nuclear translocation was also markedly increased in TA VSMCs from SHR by 12-fold versus WKY, ( p <0.01). SRF/myocardin downstream target genes, α-smooth muscle actin (α-SMA) and SM22 were increased by 3-fold in TA VSMCs in SHR vs WKY ( p <0.01). In vitro , CCG-100602, a specific inhibitor of SRF/myocardin interaction, not only strikingly repressed the increase of the expression in SRF, myocardin and the downstream targets α-SMA and SM22, but also blocked the nuclear translocation of myocardin in TA VSMCs from SHR ( p <0.01 vs untreated SHR VSMCs). However, such effects were not observed on WKY TA VSMCs. In vivo , 2-week treatment with CCG-100602 significantly reduced MAP and ASI by 19% and 63% in SHR, respectively ( p <0.01 vs untreated SHR), while aortic MAP and ASI in WKY rats remain unchanged upon the treatments. Conclusion: The activation of myocardin/SRF in aortic VSMCs presents a novel mechanism of increased aortic stiffness in SHR.

1429: Upregulation of Rho-Kinase in a Human Corpus Cavernosum Smooth Muscle Cell Line in Response to Hypoxia

2004 ◽  
Vol 171 (4S) ◽  
pp. 376-377
Author(s):  
Yongmu Zheng ◽  
Shaohua Chang ◽  
Alan J. Wein ◽  
Samuel Chacko ◽  
Michael E. DiSanto
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cell ◽  
Cell Line ◽  
Muscle Cell ◽  
Corpus Cavernosum ◽  
Rho Kinase ◽  
Muscle Cell Line

The Migration of Human Smooth Muscle Cells In Vitro Is Mediated by Plasminogen Activation and Can Be Inhibited by α2-Macroglobulin Receptor Associated Protein

1997 ◽  
Vol 78 (02) ◽  
pp. 880-886 ◽  
Author(s):  
Monique J Wijnberg ◽  
Paul H A Quax ◽  
Nancy M E Nieuwenbroek ◽  
Jan H Verheijen
Keyword(s):  
Smooth Muscle ◽  
Cell Migration ◽  
Smooth Muscle Cell ◽  
Muscle Cell ◽  
Ldl Receptor ◽  
Migration And Invasion ◽  
Invasion Assay ◽  
Plasminogen Activation ◽  
Smooth Muscle Cell Migration

SummaryThe plasminogen activation system is thought to be important in cell migration processes. A role for this system during smooth muscle cell migration after vascular injury has been suggested from several animal studies. However, not much is known about its involvement in human vascular remodelling. We studied the involvement of the plasminogen activation system in human smooth muscle cell migration in more detail using an in vitro wound assay and a matrix invasion assay. Inhibition of plasmin activity or inhibition of urokinase-type plasminogen activator (u-PA) activity resulted in approximately 40% reduction of migration after 24 h in the wound assay and an even stronger reduction (70-80%) in the matrix invasion assay. Migration of smooth muscle cells in the presence of inhibitory antibodies against tissue-type plasminogen activator (t-PA) was not significantly reduced after 24 h, but after 48 h a 30% reduction of migration was observed, whereas in the matrix invasion assay a 50% reduction in invasion was observed already after 24 h. Prevention of the interaction of u-PA with cell surface receptors by addition of soluble u-PA receptor or α2-macroglobulin receptor associated protein (RAP) to the culture medium, resulted in a similar inhibition of migration and invasion. From these results it can be concluded that both u-PA and t-PA mediated plasminogen activation can contribute to in vitro human smooth muscle cell migration and invasion. Furthermore, the interaction between u-PA and its cell surface receptor appears also to be involved in this migration and invasion process. The inhibitory effects on migration and invasion by the addition of RAP suggests an involvement of a RAP sensitive receptor of the LDL receptor family, possibly the LDL-receptor related protein (LRP) and/or the VLDL receptor.

An In Vitro Study of Nano-fiber Polymers for Guided Vascular Regeneration

2001 ◽  
Vol 711 ◽  
Author(s):  
Derick C. Miller ◽  
Anil Thapa ◽  
Karen M. Haberstroh ◽  
Thomas J. Webster
Keyword(s):  
Smooth Muscle ◽  
Cell Adhesion ◽  
Smooth Muscle Cell ◽  
Muscle Cell ◽  
Surrounding Tissue ◽  
Arterial Smooth Muscle Cell ◽  
Arterial Smooth Muscle ◽  
Cell Functions ◽  
Fiber Dimensions

ABSTRACTBiomaterials that successfully integrate into surrounding tissue should match not only the tissue's mechanical properties, but also the dimensions of the associated nano-structured extra-cellular matrix (ECM) components. The goal of this research was to use these ideals to develop a synthetic, nano-structured, polymeric biomaterial that has cytocompatible and mechanical behaviors similar to that of natural vascular tissue. In a novel manner, poly-lactic acid/polyglycolic acid (PLGA) (50/50 wt.% mix) and polyurethane were separately synthesized to possess a range of fiber dimensions in the micron and nanometer regime. Preliminary results indicated that decreasing fiber diameter on both PLGA and PU enhanced arterial smooth muscle cell adhesion; specifically, arterial smooth muscle cell adhesion increased 23% when PLGA fiber dimensions decreased from 500 to 50 nm and increased 76% on nano-structured, compared to conventional structured, polyurethane. However, nano-structured PLGA decreased endothelial cell adhesion by 52%, whereas adhesion of these same cells was increased by 50% on polyurethane. For these reasons, the present in vitro study provides the first evidence that polymer fiber dimensions can be used to selectively control cell functions for vascular prosthesis.

scholarly journals Effects of calpain and Rho-kinase inhibitors on the acrosome reaction and motility of fowl spermatozoa in vitro

Reproduction ◽  
2006 ◽  
Vol 131 (1) ◽  
pp. 71-79 ◽  
Author(s):  
K Ashizawa ◽  
G J Wishart ◽  
S Katayama ◽  
D Takano ◽  
M Maeda ◽  
...  
Keyword(s):  
Sperm Motility ◽  
Acrosome Reaction ◽  
Kinase Inhibitors ◽  
Rho Kinase ◽  
Specific Inhibitor ◽  
Immunoblot Analysis ◽  
Calpain Inhibitor ◽  
Cytoplasmic Matrix ◽  
Sperm Extract

At the avian body temperature of 40 °C, intact fowl spermatozoa require Ca2+for the initiation of motility and a combination of both Ca2+and homogenized inner perivitelline layer (IPVL) together to induce the acrosome reaction. Within the range of 1–100 μmol/l, neither PD 150606 (a Ca2+-dependent calpain inhibitor) nor Y-27632 (an inhibitor of Ca2+-dependent Rho-kinase) were able to inhibit the acrosome reaction induced by the presence of Ca2+and IPVL. However, PD 150606, although not Y-27632, was able to inhibit sperm motility initiated by Ca2+, as well as motility initiated by calyculin A – a specific inhibitor of protein phosphatases, which also initiates sperm motility at 40 °C. The addition of PD 150606 did not reduce the ATP concentrations of intact spermatozoa, nor the motility of demembranated spermatozoa. Immunoblot analysis of sperm extract using a polyclonal antibody against calpain 12 revealed a cross-reacting protein of approximately 80 kDa. These results suggest that Rho-kinase is not involved in the regulation of the acrosome reaction or of motility in fowl spermatozoa. In contrast, calpain appears to be involved in the regulation of flagellar movement, but not izn that of the acrosome reaction. Furthermore, it seems that endogenous calpain is present in the cytoplasmic matrix and/or the plasma membrane, but not retained in the axoneme and/or accessory cytoskeletal components.

Abstract 102: Cd98 Modulates Atherosclerotic Plaque Morphology by Regulating Smooth Muscle Cell Proliferation via the P-38 Map Kinase Pathway

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Sara McCurdy ◽  
Yvonne Baumer ◽  
Franz Hess ◽  
William A Boisvert
Keyword(s):  
Cell Proliferation ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Smooth Muscle Cell ◽  
Atherosclerotic Plaque ◽  
Necrotic Core ◽  
Plaque Morphology ◽  
Fibrous Cap ◽  
Plaque Area

Smooth muscle cells (SMC) are known to migrate and proliferate to form a stabilizing fibrous cap that encapsulates atherosclerotic plaques. It has been shown that CD98hc, a transmembrane protein with a known role in amino acid transport and integrin signaling, is involved in proliferation and survival of various cell types including SMC. Based on these data, we hypothesized that CD98hc deficiency selectively in SMC would have pathogenic effects on atherosclerosis development and plaque composition. To test this, we utilized mice with SMC-specific deletion of the CD98hc ( CD98hc fl/fl SM22Cre + ) to determine the effects of CD98hc deficiency on SMC function in the context of atherosclerosis. We performed in vitro proliferation and survival/apoptosis assays to investigate the role of CD98hc in the proliferation and survival of primary mouse aortic vascular smooth muscle cells. We found that VSMC isolated from whole aortas of CD98hc -/- animals displayed approximately 60% reduced cell counts compared to control (41 ± 8.2% of control) after 5 days in culture. EdU assays in vivo showed a defect in the ability of CD98hc -/- SMC to proliferate, with 25% reduction in EdU-positive VSMC compared to controls (2.3 ± 0.2% vs 3 ± 0.2%). In addition, caspase-3 staining of SMC in vitro displayed a 41% increase in propensity of CD98hc -/- SMC to undergo apoptosis compared to controls (7.9 ± 0.6% vs 5.6 ± 0.5%). Furthermore, the absence of CD98hc in SMC caused a sharp increase in phosphorylated p-38, which was partially abrogated towards control levels when the cells were treated with PDGF-BB to induce proliferation. Long-term atherosclerosis study using SMC-CD98hc -/- /LDLR -/- mice showed that atherosclerotic plaque morphology was altered with increased necrotic core area (25.8 ± 1.9% vs 10.9 ± 1.6% necrotic core area per plaque area) due to a reduction in infiltration of SMC within the plaque (2.1 ± 0.4% vs 4.3 ± 0.4% SM22α positive area per plaque area) compared to control LDLR -/- mice. These data support an important role for CD98hc and its regulation of p-38 MAP kinase signaling in aortic vascular smooth muscle cell proliferation and survival. We conclude that CD98hc is critical for the formation of fibrous cap that is important in maintaining the stability of atherosclerotic plaque.

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