scholarly journals Gene transfer of dominant negative Rho kinase suppresses neointimal formation after balloon injury in pigs

2000 ◽  
Vol 278 (6) ◽  
pp. H1744-H1750 ◽  
Author(s):  
Yasuhiro Eto ◽  
Hiroaki Shimokawa ◽  
Junko Hiroki ◽  
Kunio Morishige ◽  
Tadashi Kandabashi ◽  
...  
Keyword(s):  
Gene Transfer ◽  
Rho Kinase ◽  
Dominant Negative ◽  
Balloon Injury ◽  
Cellular Functions ◽  
Neointimal Formation ◽  
Stenotic Lesion ◽  
Dominant Negative Form

Restenosis after angioplasty still remains a major problem for which neointimal formation appears to play an important role. Recent studies in vitro suggested that Rho kinase, a target protein of Rho, is important in various cellular functions. We thus examined whether Rho kinase is involved in the restenotic changes after balloon injury. In vivo gene transfer was performed immediately after balloon injury in both sides of the porcine femoral arteries with adenoviral vector encoding either a dominant negative form of Rho kinase (AdDNRhoK) or β-galactosidase (AdLacZ) as a control. One week after the transfer, immunohistochemistry confirmed the successful gene expression in the vessel wall, whereas 2 wk after the transfer, Western blotting showed the functional upregulation of Rho kinase at the AdLacZ site and its suppression at the AdDNRhoK site. Angiography showed the development of a stenotic lesion at the AdLacZ site where histological neointimal formation was noted, whereas those changes were significantly suppressed at the AdDNRhoK site. These results indicate that Rho kinase is involved in the pathogenesis of neointimal formation after balloon injury in vivo.

Intramuscular gene transfer of CGRP inhibits neointimal hyperplasia after balloon injury in the rat abdominal aorta

2004 ◽  
Vol 287 (4) ◽  
pp. H1582-H1589 ◽  
Author(s):  
Wang Wang ◽  
Wei Sun ◽  
Xian Wang
Keyword(s):  
Nitric Oxide ◽  
Gene Transfer ◽  
Neointimal Hyperplasia ◽  
Rat Aorta ◽  
Nitric Oxide Donor ◽  
Protective Effects ◽  
Balloon Injury ◽  
Neointimal Formation

CGRP is a well-known neuropeptide that has various protective effects on cardiovascular system. Our previous studies have shown that CGRP inhibits vascular smooth muscle cell (VSMC) proliferation in vitro. The present study aimed to explore the role of the CGRP in neointimal formation after balloon injury in the rat aortic wall and the underlying mechanism. Gene transfer of CGRP was performed with the use of intramuscular electroporation in a balloon-injured rat aorta model. Apoptosis in VSMCs was determined by electrophoresis assessment of DNA fragmentation and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling assay. Overexpression of the CGRP gene significantly inhibited the neointimal formation after balloon injury compared with the mock transfer, as assessed by the intima-to-media ratio 14 days after balloon injury (29.2 ± 3.7% vs. 52.7 ± 5.4%; n = 9–12, P < 0.05). In addition, CGRP gene expression increased the number of apoptotic cells in the neointima in vivo 14 days after balloon injury. Similarly, the addition of bioactive CGRP and the nitric oxide donor induced similar apoptosis in cultured VSMCs. The antagonist of the CGRP1 receptor and inhibitors of cAMP-PKA and nitric oxide blocked CGRP-mediated apoptosis. Furthermore, CGRP gene transfer increased inducible nitric oxide synthase and p53 but decreased PCNA and Bcl-2 protein levels in balloon-injured rat aorta. Our data demonstrated that CGRP potently inhibited neointimal thickening in the rat aorta, at least in part through its distinct effects on apoptosis and proliferation of VSMCs both in vivo and in vitro. Therefore, delivery of the CGRP gene may have therapeutic implications in limiting vascular restenosis.

Regulation of Hox target genes by a DNA bound Homothorax/Hox/Extradenticle complex

Development ◽  
1999 ◽  
Vol 126 (22) ◽  
pp. 5137-5148 ◽  
Author(s):  
H.D. Ryoo ◽  
T. Marty ◽  
F. Casares ◽  
M. Affolter ◽  
R.S. Mann
Keyword(s):  
Nuclear Localization ◽  
Target Genes ◽  
Dominant Negative ◽  
Homeodomain Protein ◽  
Hox Proteins ◽  
Trimeric Complex ◽  
Binding Residue ◽  
Dominant Negative Form

To regulate their target genes, the Hox proteins of Drosophila often bind to DNA as heterodimers with the homeodomain protein Extradenticle (EXD). For EXD to bind DNA, it must be in the nucleus, and its nuclear localization requires a third homeodomain protein, Homothorax (HTH). Here we show that a conserved N-terminal domain of HTH directly binds to EXD in vitro, and is sufficient to induce the nuclear localization of EXD in vivo. However, mutating a key DNA binding residue in the HTH homeodomain abolishes many of its in vivo functions. HTH binds to DNA as part of a HTH/Hox/EXD trimeric complex, and we show that this complex is essential for the activation of a natural Hox target enhancer. Using a dominant negative form of HTH we provide evidence that similar complexes are important for several Hox- and exd-mediated functions in vivo. These data suggest that Hox proteins often function as part of a multiprotein complex, composed of HTH, Hox, and EXD proteins, bound to DNA.

scholarly journals Heparan Sulfate-dependent RAGE oligomerization is indispensable for pathophysiological functions of RAGE

2021 ◽  
Author(s):  
Miaomiao Li ◽  
Chih Yean Ong ◽  
Christophe J Langouet-Astrie ◽  
Lisi TAN ◽  
Ashwni Verma ◽  
...  
Keyword(s):  
Heparan Sulfate ◽  
Genetic Model ◽  
Point Mutations ◽  
Active Role ◽  
Dominant Negative ◽  
Unexpected Finding ◽  
Rna Seq ◽  
Dominant Negative Form

RAGE, a druggable inflammatory receptor, is known to function as an oligomer but the exact oligomerization mechanism remains poorly understood. Previously we have shown that heparan sulfate (HS) plays an active role in RAGE oligomerization. To understand the physiological significance of HS-induced RAGE oligomerization in vivo, we generated RAGE knock-in mice (RageAHA/AHA) by introducing point mutations to specifically disrupt HS-RAGE interaction. The RAGE mutant demonstrated normal ligand-binding but impaired capacity of HS-binding and oligomerization. Remarkably, RageAHA/AHA mice phenocopied Rage-/- mice in two different pathophysiological processes, namely bone remodeling and neutrophil-mediated liver injury, which demonstrates that HS-induced RAGE oligomerization is essential for RAGE signaling. Our findings suggest that it should be possible to block RAGE signaling by inhibiting HS-RAGE interaction. To test this, we generated a monoclonal antibody that targets the HS-binding site of RAGE. This antibody blocks RAGE signaling in vitro and in vivo, recapitulating the phenotype of RageAHA/AHA mice. By inhibiting HS-RAGE interaction genetically and pharmacologically, our work validated an alternative strategy to antagonize RAGE. Finally, we have performed RNA-seq analysis of neutrophils and lungs and found that while Rage-/- mice had a broad alteration of transcriptome in both tissues compared to wild-type mice, the changes of transcriptome in RageAHA/AHA mice were much more restricted. This unexpected finding suggests that by preserving the expression of RAGE protein (in a dominant-negative form), RageAHA/AHA mouse might represent a cleaner genetic model to study physiological roles of RAGE in vivo compared to Rage-/- mice.

scholarly journals Periadventitial atRA citrate-based polyester membranes reduce neointimal hyperplasia and restenosis after carotid injury in rats

2014 ◽  
Vol 307 (10) ◽  
pp. H1419-H1429 ◽  
Author(s):  
Elaine K. Gregory ◽  
Antonio R. Webb ◽  
Janet M. Vercammen ◽  
Megan E. Flynn ◽  
Guillermo A. Ameer ◽  
...  
Keyword(s):  
High Performance ◽  
Neointimal Hyperplasia ◽  
Arterial Injury ◽  
Macrophage Infiltration ◽  
Appreciable Effect ◽  
Balloon Injury ◽  
Neointimal Formation ◽  
The Impact

Oral all-trans retinoic acid (atRA) has been shown to reduce the formation of neointimal hyperplasia; however, the dose required was 30 times the chemotherapeutic dose, which already has reported side effects. As neointimal formation is a localized process, new approaches to localized delivery are required. This study assessed whether atRA within a citrate-based polyester, poly(1,8 octanediolcitrate) (POC), perivascular membrane would prevent neointimal hyperplasia following arterial injury. atRA-POC membranes were prepared and characterized for atRA release via high-performance liquid chromatography with mass spectrometry detection. Rat adventitial fibroblasts (AF) and vascular smooth muscle cells (VSMC) were exposed to various concentrations of atRA; proliferation, apoptosis, and necrosis were assessed in vitro. The rat carotid artery balloon injury model was used to evaluate the impact of the atRA-POC membranes on neointimal formation, cell proliferation, apoptosis, macrophage infiltration, and vascular cell adhesion molecule 1 (VCAM-1) expression in vivo. atRA-POC membranes released 12 μg of atRA over 2 wk, with 92% of the release occurring in the first week. At 24 h, atRA (200 μmol/l) inhibited [3H]-thymidine incorporation into AF and VSMC by 78% and 72%, respectively (* P = 0.001), with negligible apoptosis or necrosis. Histomorphometry analysis showed that atRA-POC membranes inhibited neointimal formation after balloon injury, with a 56%, 57%, and 50% decrease in the intimal area, intima-to-media area ratio, and percent stenosis, respectively ( P = 0.001). atRA-POC membranes had no appreciable effect on apoptosis or proliferation at 2 wk. Regarding biocompatibility, we found a 76% decrease in macrophage infiltration in the intima layer ( P < 0.003) in animals treated with atRA-POC membranes, with a coinciding 53% reduction in VCAM-1 staining ( P < 0.001). In conclusion, perivascular delivery of atRA inhibited neointimal formation and restenosis. These data suggest that atRA-POC membranes may be suitable as localized therapy to inhibit neointimal hyperplasia following open cardiovascular procedures.

In vivo Gene Transfer of Dominant-Negative Rho-Kinase Induces Regression of Coronary Arteriosclerosis in Pigs

2006 ◽  
Vol 947 (1) ◽  
pp. 407-411 ◽  
Author(s):  
KUNIO MORISHIGE ◽  
HIROAKI SHIMOKAWA ◽  
YASUHIRO ETO ◽  
MASAHIKO HOSHIJIMA ◽  
KOZO KAIBUCHI ◽  
...  
Keyword(s):  
Gene Transfer ◽  
Rho Kinase ◽  
Dominant Negative ◽  
Coronary Arteriosclerosis ◽  
In Vivo Gene Transfer

scholarly journals The BD2 domain of BRD4 is a determinant in EndoMT and vein graft neointima formation

2019 ◽  
Author(s):  
Mengxue Zhang ◽  
Bowen Wang ◽  
Go Urabe ◽  
Yitao Huang ◽  
Jorge Plutzky ◽  
...  
Keyword(s):  
Vein Graft ◽  
Dominant Negative ◽  
State Transitions ◽  
Wall Thickening ◽  
Neointima Formation ◽  
Neointimal Formation ◽  
Jugular Veins ◽  
Mesenchymal Transition

AbstractBackgroundVein-graft bypass is commonly performed to overcome atherosclerosis but is limited by high failure rates, principally due to neointimal wall thickening. Recent studies reveal that endothelial-mesenchymal transition (EndoMT) is critical for vein-graft neointima formation. BETs are a family of Bromo/ExtraTerminal domains-containing epigenetic reader proteins (BRD2, BRD3, BRD4). They bind acetylated histones through their unique tandem bromodomains (BD1, BD2), facilitating transcriptional complex formation and cell-state transitions. The role for BETs, including individual BRDs and their unique BDs, is not well understood in EndoMT and neointimal formation.Methods and ResultsRepression of BRD4 expression abrogated TGFβ1-induced EndoMT, with greater effects than BRD2 or BRD3 knockdown. An inhibitor selective for BD2 in all BETs, but not that for BD1, blocked EndoMT. Moreover, expression of a dominant-negative BRD4-specific BD2 fully abolished EndoMT. Concordantly, BRD4 knockdown repressed TGFβ1-stimulated increase of ZEB1 protein – a transcription factor integral in EndoMT. In vivo, lentiviral gene transfer of either BRD4 shRNA or dominant negative BRD4-specific BD2 mitigated neointimal development in rat jugular veins grafted to carotid arteries.ConclusionsOur data reveal the BD2 domain of BRD4 as a determinant driving EndoMT in vitro and neointimal formation in vivo. These findings provide new insight into BET biology, while offering prospects of specific BET domain targeting as an approach to limiting neointima and extending vein graft patency.

scholarly journals Selection of a Dominant Negative Retinoblastoma Protein (RB) Inhibiting Satellite Myoblast Differentiation Implies an Indirect Interaction between MyoD and RB

2000 ◽  
Vol 20 (14) ◽  
pp. 5129-5139 ◽  
Author(s):  
Feng-Qian Li ◽  
Archie Coonrod ◽  
Marshall Horwitz
Keyword(s):  
Myogenic Differentiation ◽  
Retinoblastoma Protein ◽  
Dominant Negative ◽  
Myoblast Differentiation ◽  
Loss Of Function ◽  
Lysosomal Protease ◽  
Dominant Negative Form ◽  
Genes Encoding

ABSTRACT Satellite myoblasts serve as stem cells in postnatal skeletal muscle, but the genes responsible for choosing between growth versus differentiation are largely undefined. We have used a novel genetic approach to identify genes encoding proteins whose dominant negative inhibition is capable of interrupting the in vitro differentiation of C2C12 murine satellite myoblasts. The screen is based on fusion of a library of cDNA fragments with the lysosomal protease cathepsin B (CB), such that the fusion protein intracellularly diverts interacting factors to the lysosome. Among other gene fragments selected in this screen, including those of known and novel sequence, is the retinoblastoma protein (RB) pocket domain. This unique dominant negative form of RB allows us to genetically determine if MyoD and RB associate in vivo. The dominant negative CB-RB fusion produces a cellular phenotype indistinguishable from recessive loss of function RB mutations. The fact that the dominant negative RB inhibits myogenic differentiation in the presence of nonlimiting concentrations of either RB or MyoD suggests that these two proteins do not directly interact. We further show that the dominant negative RB inhibits E2F1 but cannot inhibit a forced E2F1-RB dimer. Therefore, E2F1 is a potential mediator of the dominant negative inhibition of MyoD by CB-RB during satellite cell differentiation. We propose this approach to be generally suited to the investigation of gene function, even when little is known about the pathway being studied.

scholarly journals Superoxide scavenging and Akt inhibition in myocardium ameliorate pressure overload-induced NF-κB activation and cardiac hypertrophy

2010 ◽  
Vol 41 (2) ◽  
pp. 127-136 ◽  
Author(s):  
Shawn D. Hingtgen ◽  
Zhenbo Li ◽  
William Kutschke ◽  
Xin Tian ◽  
Ram V. Sharma ◽  
...  
Keyword(s):  
Cardiac Hypertrophy ◽  
Viral Vectors ◽  
Pressure Overload ◽  
Dominant Negative ◽  
Cardiomyocyte Hypertrophy ◽  
Luciferase Expression ◽  
Akt Activation ◽  
Dominant Negative Form

Recent studies from our laboratory and others have shown that increases in cytoplasmic superoxide (O2·−) levels and Akt activation play a key role in agonist-stimulated NF-κB activation and cardiomyocyte hypertrophy in vitro. In this study, we tested the hypothesis that adenovirus (Ad)-mediated intramyocardial gene transfer of cytoplasmic superoxide dismutase (AdCu/ZnSOD) or a dominant-negative form of Akt (AdDNAkt) in mice would attenuate pressure overload-induced increases in activation of the redox-sensitive transcription factor NF-κB and cardiac hypertrophy. Adult C57BL/6 mice were subjected to thoracic aortic banding (TAB) or sham surgery, and intramyocardial injections of viral vectors (AdCu/ZnSOD, AdDNAkt, or control) were performed. There was robust transgene expression in the heart, which peaked 6–7 days after injection and then declined to undetectable levels by 12–14 days. In mice injected with AdBgL II, TAB caused a significant increase in O2·− generation and cardiac mass at 1 wk, and these responses were markedly attenuated by AdCu/ZnSOD. In addition, TAB induced time-dependent activation of NF-κB in the myocardium as measured longitudinally by in vivo bioluminescent imaging of NF-κB-dependent luciferase expression. This was also abolished by intracardiac AdCu/ZnSOD or AdDNAkt, but not the control vector. The inhibition of Akt and O2·−-mediated NF-κB activation in TAB hearts was associated with an attenuation of cardiac hypertrophy. Since a direct cause-and-effect relationship between NF-κB activation and cardiomyocyte hypertrophy has been established previously, our data support the hypothesis that increased O2·− generation and Akt activation are key signaling intermediates in pressure overload-induced activation of NF-κB and cardiac hypertrophy.

scholarly journals FOXA1 plays a role in regulating secretoglobin 1a1 expression in the absence of CCAAT/enhancer binding protein activities in lung in vivo

2011 ◽  
Vol 300 (3) ◽  
pp. L441-L452 ◽  
Author(s):  
Taketomo Kido ◽  
Takeshi Tomita ◽  
Minoru Okamoto ◽  
Yan Cai ◽  
Yoshimi Matsumoto ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Regulation Of Gene Expression ◽  
Dominant Negative ◽  
Clara Cell ◽  
Small Molecular Weight ◽  
Dominant Negative Form

Secretoglobin (SCGB) 1A1, also called Clara cell secretor protein (CCSP) or Clara cell-specific 10-kDa protein (CC10), is a small molecular weight secreted protein mainly expressed in lung, with anti-inflammatory/immunomodulatory properties. Previous in vitro studies demonstrated that CCAAT/enhancer-binding proteins (C/EBPs) are the major transcription factors for the regulation of Scbg1a1 gene expression, whereas FOXA1 had a minimum effect on the transcription. To determine the in vivo role of C/EBPs in the regulation of SCGB1A1 expression, experiments were performed in which A-C/EBP, a dominant-negative form of C/EBP that interferes with DNA binding activities of all C/EBPs, was specifically expressed in lung. Surprisingly, despite the in vitro findings, expression of SCGB1A1 mRNA was not decreased in vivo in the absence of C/EBPs. This may be due to a compensatory role assumed by FOXA1 in the regulation of Scgb1a1 gene expression in lung in the absence of active C/EBPs. This disconnect between in vitro and in vivo results underscores the importance of studies using animal models to determine the role of specific transcription factors in the regulation of gene expression in intact multicellular complex organs such as lung.

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