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Find video protocols related to scientific articles indexed in Pubmed.
Metastatic tumor antigen in hepatocellular carcinoma: golden roads toward personalized medicine.
Cancer Metastasis Rev.
PUBLISHED: 10-19-2014
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Hepatocellular carcinoma (HCC), a prototype of hypervascular tumors, is one of the most common malignancies in the world, especially hyperendemic in the Far East where chronic hepatitis B virus (HBV) infection is highly prevalent. It is characterized by the clinical feature of a poor prognosis or a high mortality due to its already far advanced stages at diagnosis. It is so multifactorial that hepatocarcinogenesis cannot be explained by a single molecular mechanism. To date, a number of pathways have been known to contribute to the development, growth, angiogenesis, and even metastasis of HCC. Among the various factors, metastatic tumor antigens (MTAs) or metastasis-associated proteins have been vigorously investigated as an intriguing target in the field of hepatocarcinogenesis. According to recent studies including ours, MTAs are not only involved in the HCC development and growth (molecular carcinogenesis), but also closely associated with the post-operative recurrence and a poor prognosis or a worse response to post-operative anti-cancer therapy (clinical significance). Herein, we review MTAs in light of their essential structure, functions, and molecular mechanism in hepatocarcinogenesis. We will also focus in detail on the interaction between hepatitis B x protein (HBx) of HBV and MTA in order to clarify the HBV-associated HCC development. Finally, we will discuss the prognostic significance and clinical application of MTA in HCC. We believe that this review will help clinicians to understand the meaning and use of the detection of MTA in order to more effectively manage their HCC patients.
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Silencing histone deacetylase 2 using small hairpin RNA induces regression of fibrotic plaque in a rat model of Peyronie's disease.
BJU Int.
PUBLISHED: 08-13-2014
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To examine the therapeutic effect of adenovirus encoding histone deacetylase 2 (HDAC2) small hairpin RNA (Ad-HDAC2 shRNA) in a rat model of Peyronie's disease (PD) and to determine the mechanisms by which HDAC2 knockdown ameliorates fibrotic responses in primary fibroblasts derived from human PD plaque.
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Inhibition of Ninjurin 1 restores erectile function through dual angiogenic and neurotrophic effects in the diabetic mouse.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-16-2014
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Penile erection is a neurovascular phenomenon, and erectile dysfunction (ED) is caused mainly by vascular risk factors or diseases, neurologic abnormalities, and hormonal disturbances. Men with diabetic ED often have severe endothelial dysfunction and peripheral nerve damage, which result in poor response to oral phosphodiesterase-5 inhibitors. Nerve injury-induced protein 1 (Ninjurin 1, Ninj1) is known to be involved in neuroinflammatory processes and to be related to vascular regression during the embryonic period. Here, we demonstrate in streptozotocin-induced diabetic mice that inhibition of the Ninj1 pathway by administering Ninj1-neutralizing antibody (Ninj1-Ab) or by using Ninj1-knockout mice successfully restored erectile function through enhanced penile angiogenesis and neural regeneration. Angiopoietin-1 (Ang1) expression was down-regulated and angiopoietin-2 expression was up-regulated in the diabetic penis compared with that in controls, and these changes were reversed by treatment with Ninj1-Ab. Ninj1 blockade-mediated penile angiogenesis and neural regeneration as well as recovery of erectile function were abolished by inhibition of Ang1-Tie2 (tyrosine kinase with Ig and epidermal growth factor homology domain-2) signaling with soluble Tie2 antibody or Ang1 siRNA. The present results suggest that inhibition of the Ninj1 pathway will be a novel therapeutic strategy for treating ED.
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Ninjurin1 enhances the basal motility and transendothelial migration of immune cells by inducing protrusive membrane dynamics.
J. Biol. Chem.
PUBLISHED: 06-10-2014
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Ninjurin1 is involved in the pathogenesis of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, by mediating leukocyte extravasation, a process that depends on homotypic binding. However, the precise regulatory mechanisms of Ninjurin1 during inflammation are largely undefined. We therefore examined the pro-migratory function of Ninjurin1 and its regulatory mechanisms in macrophages. Interestingly, Ninjurin1-deficient bone marrow-derived macrophages exhibited reduced membrane protrusion formation and dynamics, resulting in the impairment of cell motility. Furthermore, exogenous Ninjurin1 was distributed at the membrane of filopodial structures in Raw264.7 macrophage cells. In Raw264.7 cells, RNA interference of Ninjurin1 reduced the number of filopodial projections, whereas overexpression of Ninjurin1 facilitated their formation and thus promoted cell motility. Ninjurin1-induced filopodial protrusion formation required the activation of Rac1. In Raw264.7 cells penetrating an MBEC4 endothelial cell monolayer, Ninjurin1 was localized to the membrane of protrusions and promoted their formation, suggesting that Ninjurin1-induced protrusive activity contributed to transendothelial migration. Taking these data together, we conclude that Ninjurin1 enhances macrophage motility and consequent extravasation of immune cells through the regulation of protrusive membrane dynamics. We expect these findings to provide insight into the understanding of immune responses mediated by Ninjurin1.
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Intracavernous delivery of stromal vascular fraction restores erectile function through production of angiogenic factors in a mouse model of cavernous nerve injury.
J Sex Med
PUBLISHED: 06-05-2014
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Erectile dysfunction (ED) is a major complication of radical prostatectomy. Men with radical prostatectomy-induced ED respond less positively to oral phosphodiesterase-5 inhibitors.
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Sonic hedgehog secreted by neurons regulates angiopoietin expression in neighboring fibroblasts.
Int. J. Mol. Med.
PUBLISHED: 01-22-2014
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Lately, the importance of the communication between different cell types and the understanding of the cell communication pathway has been emphasized, as it may provide a novel therapeutic strategy for the regeneration of damaged tissue. In the present study, we suggest that sonic hedgehog (Shh) is a mediator of cell communication between neurons and fibroblasts. Recombinant Shh (rShh) affected the expression of the angiogenic factors, angiopoietin (Ang)-1 and Ang-2, in fibroblasts, but not in neurons or neural progenitor cells (NPCs). The expression of the Shh downstream transcription factor, Gli1, was markedly increased in neurons and NPCs, indicating that neurons and NPCs responded to rShh. However, rShh did not affect Ang-1 and Ang-2 expression in neurons and NPCs. It should be noted that Shh was strongly expressed in neurons, but that Shh expression was undetectable in fibroblasts. We performed a co-culture assay using neurons and fibroblasts to investigate whether the expression of Ang-1 and Ang-2 is regulated by cell communication, without rShh treatment. Ang-1 expression in fibroblasts was markedly upregulated by co-culture with neurons, whereas Ang-2 expression was decreased by co-culture with neurons. Moreover, when an Shh-neutralizing antibody was added, this effect was diminished. Collectively, our data suggest that Shh-expressing neurons regulate angiopoietin expression in neighboring fibroblasts in a paracrine manner.
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Effectiveness of intracavernous delivery of adenovirus encoding Smad7 gene on erectile function in a mouse model of cavernous nerve injury.
J Sex Med
PUBLISHED: 01-18-2014
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Men with erectile dysfunction (ED) respond poorly to oral phosphodiesterase-5 inhibitors following radical prostatectomy. Recent studies have reported that up-regulation of transforming growth factor-?1 (TGF-?1) and activation of the Smad signaling pathway play important roles in cavernous fibrosis and in the deterioration of erectile function in a mouse model of cavernous nerve injury (CNI) and in patients with spinal cord injury. The mothers against decapentaplegic homolog 7 (Smad7) is known to inhibit the phosphorylation of Smad2 and Smad3.
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Xenogenic transplantation of human breast adipose-derived stromal vascular fraction enhances recovery of erectile function in diabetic mice.
Biol. Reprod.
PUBLISHED: 01-01-2014
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The adipose tissue-derived stromal vascular fraction (SVF) is an ideal source of stem and stromal cells. The aim of this study was to examine whether and how xenogenic transplantation of human breast SVF restores erectile function in diabetic mice. Human SVF was isolated from five patients (age, 20-45 yr) undergoing reduction mammoplasty. Eight-week-old C57BL/6J mice were used, and diabetes was induced by intraperitoneal injection of streptozotocin. At 8 wk after induction of diabetes, the animals were randomly distributed into controls and diabetic mice treated with a single intracavernous injection of PBS, human SVF at different concentrations, or human SVF lysate. Two weeks later, erectile function was measured by cavernous nerve stimulation, and the penis was then harvested for biochemical examinations. Erectile function was significantly improved in diabetic mice treated with human SVF (2 × 10(5), 5 × 10(5), and 1 × 10(6) cells/20 ?l) and SVF lysate. Human SVF treatment in diabetic mice significantly increased cavernous endothelial and smooth muscle cell contents, induced eNOS phosphorylation, and restored penile nNOS-positive nerve fibers. Human SVF lysate induced secretion of angiogenic factors and expression of their receptors. Human SVF did not increase serum levels of proinflammatory cytokines. A limitation of this study was that the exact composition of the human SVF was not examined. In summary, xenogenic transplantation of human SVF did not induce systemic inflammation and successfully improved erectile function in diabetic mice through enhanced penile angiogenesis and neural regeneration.
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Effect of intracavernous administration of angiopoietin-4 on erectile function in the streptozotocin-induced diabetic mouse.
J Sex Med
PUBLISHED: 08-12-2013
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Erectile dysfunction (ED) is a highly prevalent complication of diabetes, and the severity of endothelial dysfunction is one of the most important factors in reduced responsiveness to oral phosphodiesterase type 5 inhibitors.
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Expression of the Apelin-APJ Pathway and Effects on Erectile Function in a Mouse Model of Vasculogenic Erectile Dysfunction.
J Sex Med
PUBLISHED: 04-11-2013
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Much attention has recently been focused on therapeutic angiogenesis as a treatment for erectile dysfunction (ED). The apelin and apelin receptor (APJ) system is known to cause endothelium-dependent vasodilatation and to be involved in angiogenesis.
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Nerve injury-induced protein 1 (Ninjurin-1) is a novel therapeutic target for cavernous nerve injury-induced erectile dysfunction in mice.
J Sex Med
PUBLISHED: 04-02-2013
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Radical prostatectomy for prostate cancer can not only induce cavernous nerve injury (CNI) but also result in structural changes in the cavernous tissues. Nerve injury-induced protein 1, Ninjurin-1 (Ninj1), is known to be involved in neuroinflammatory processes and to be related to vascular regression during the embryonic period.
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Erectile dysfunction precedes other systemic vascular diseases due to incompetent cavernous endothelial cell-cell junctions.
J. Urol.
PUBLISHED: 02-21-2013
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Erectile dysfunction is often a harbinger of cardiovascular disease. We sought to gain mechanistic insight at the cellular and molecular levels into why erectile dysfunction precedes the clinical consequences of cardiovascular disease.
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Inhibition of histone deacetylase 2 mitigates profibrotic TGF-?1 responses in fibroblasts derived from Peyronies plaque.
Asian J. Androl.
PUBLISHED: 01-28-2013
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Epigenetic modifications, such as histone acetylation/deacetylation, have been shown to play a role in the pathogenesis of fibrotic disease. Peyronies disease (PD) is a localized fibrotic process of the tunica albuginea, which leads to penile deformity. This study was undertaken to determine the anti-fibrotic effect of small interfering RNA (siRNA)-mediated silencing of histone deacetylase 2 (HDAC2) in primary fibroblasts derived from human PD plaque. PD fibroblasts were pre-treated with HDAC2 siRNA and then stimulated with transforming growth factor-?1 (TGF-?1). Protein was extracted from treated fibroblasts for Western blotting and the membranes were probed with antibody to phospho-Smad2/Smad2, phospho-Smad3/Smad3, smooth muscle ?-actin and extracellular matrix proteins, including plasminogen activator inhibitor-1, fibronectin, collagen I and collagen IV. We also performed immunocytochemistry to detect the expression of extracellular matrix proteins and to examine the effect of HDAC2 siRNA on the TGF-?1-induced nuclear translocation of Smad2/3 in fibroblasts. Knockdown of HDAC2 in PD fibroblasts abrogated TGF-?1-induced extracellular matrix production by blocking TGF-?1-induced phosphorylation and nuclear translocation of Smad2 and Smad3, and by inhibiting TGF-?1-induced transdifferentiation of fibroblasts into myofibroblasts. Decoding the individual function of the HDAC isoforms by use of siRNA technology, preferably siRNA for HDAC2, may lead to the development of specific and safe epigenetic therapies for PD.
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Snail as a potential target molecule in cardiac fibrosis: paracrine action of endothelial cells on fibroblasts through snail and CTGF axis.
Mol. Ther.
PUBLISHED: 01-04-2013
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Ischemia/reperfusion (I/R) injury to myocardium induces death of cardiomyocytes and destroys the vasculature, leading to cardiac fibrosis that is mainly mediated by the transdifferentiation of fibroblasts to myofibroblasts and the collagen deposition. Snail involvement in fibrosis is well known; however, the contribution of Snail to cardiac fibrosis during I/R injury and its underlying mechanisms have not been defined. We showed that I/R injury to mouse hearts significantly increases the expression of Snail. An in vitro hypoxia/reoxygenation (Hy/Reoxy) experiment showed that the cell source of Snail induction is endothelial cells rather than cardiac fibroblasts (cFibroblasts) or cardiomyoblasts. When Snail was overexpressed in endothelial cells, they underwent endothelial-to-mesenchymal transition (EndMT) but showed very poor capacity for collagen synthesis. Instead, reoxygenation- or Snail overexpression-mediated EndMT-like cells noticeably stimulated transdifferentiation of fibroblasts to myofibroblasts via secretion of connective tissue growth factor (CTGF). The injection of a peroxisome proliferator-activated receptor-? (PPAR-?) agonist, a selective Snail inhibitor, remarkably suppressed collagen deposition and cardiac fibrosis in mouse I/R injury, and significantly improved cardiac function and reduced Snail and CTGF expression in vivo. Our findings suggested a new mechanism of cell-to-cell communication between EndMT-like cells and fibroblasts for fibrosis induction and implicated Snail as a potential target molecule in cardiac fibrosis after I/R injury.
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Intracavernous delivery of a designed angiopoietin-1 variant rescues erectile function by enhancing endothelial regeneration in the streptozotocin-induced diabetic mouse.
Diabetes
PUBLISHED: 01-26-2011
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Patients with diabetic erectile dysfunction often have severe endothelial dysfunction and respond poorly to oral phosphodiesterase-5 inhibitors. We examined the effectiveness of the potent angiopoietin-1 (Ang1) variant, cartilage oligomeric matrix protein (COMP)-Ang1, in promoting cavernous endothelial regeneration and restoring erectile function in diabetic animals.
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Increased cavernous expression of transforming growth factor-?1 and activation of the Smad signaling pathway affects erectile dysfunction in men with spinal cord injury.
J Sex Med
PUBLISHED: 10-04-2010
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Transforming growth factor-?1 (TGF-?1) is implicated in bladder fibrosis after spinal cord injury (SCI) and in the fibrosis in the corpus cavernosum tissue after cavernous nerve injury.
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Inhibition of endothelial cell migration through the down?regulation of MMP-9 by A-kinase anchoring protein 12.
Mol Med Rep
PUBLISHED: 07-01-2010
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Matrix metalloproteinases (MMPs) play an important role in the degradation of extracellular matrix (ECM) molecules. ECM degradation is associated with tumor metastasis and angiogenesis. Therefore, the regulation of MMPs is of potential benefit in the treatment of various diseases, including cancer. A-kinase anchoring protein 12 (AKAP12) has been identified as a potential tumor suppressor. However, the function of AKAP12 as a tumor suppressor is not well understood. Herein, to determine the relationship between AKAP12 and MMP-9 in cancer, we first investigated the expression of MMP-9 under normoxic and hypoxic conditions in human fibrosarcoma cells. The expression of MMP-9 was not detected under normoxic conditions.; however, it was markedly increased under hypoxia in HT1080 cells. The effect of AKAP12 on the expression of MMP-9 was subsequently investigated. Hypoxia-induced MMP-9 mRNA expression was significantly reduced by overexpression of AKAP12, as was MMP-9 protein expression. In addition, when the AKAP12 transfectant-conditioned media (CM) were transferred into human endothelial cells, cell migration was significantly inhibited compared to the control group. Notably, the inhibition of AKAP12 expression by siRNA targeting AKAP12 resulted in an increase in the expression of active MMP-2 under normoxia, as well as of MMP-9. Endothelial cell migration was also strongly increased by treatment with CM of siRNA against AKAP12, as compared to the control group. Taken together, the results indicate that AKAP12 is involved in the regulation of endothelial cell migration through the inhibitory regulation of MMP-9 expression in tumor cells.
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Intracavernous delivery of synthetic angiopoietin-1 protein as a novel therapeutic strategy for erectile dysfunction in the type II diabetic db/db mouse.
J Sex Med
PUBLISHED: 06-30-2010
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Patients with erectile dysfunction (ED) associated with type II diabetes often have impaired endothelial function and tend to respond poorly to oral phosphodiesterase type 5 inhibitors. Therefore, neovascularization is a promising strategy for curing diabetic ED.
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Plasma and brain matrix metalloproteinase-9 after acute focal cerebral ischemia in rats.
Stroke
PUBLISHED: 06-25-2009
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Plasma levels of matrix metalloproteinase-9 (MMP-9) have been proposed to be a useful biomarker for assessing pathological events in brain. Here, we examined the temporal profiles of MMP-9 in blood and brain using a rat model of acute focal cerebral ischemia.
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Neuromedin B induces angiogenesis via activation of ERK and Akt in endothelial cells.
Exp. Cell Res.
PUBLISHED: 04-28-2009
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Neuromedin B (NMB) is one of the bombesin-like peptides in mammals. Recently, bombesin-like peptides have been characterized as growth factors in highly vascularized tumors. In this study, we report that NMB potently stimulates in vivo neovascularization in a mouse Matrigel plug and the sprouting of endothelial cells ex vivo in rat aortic rings. In addition, NMB increases the migration and tube formation in human umbilical vein endothelial cells (HUVECs). Moreover, treatment of HUVECs with NMB activates the extracellular signal-regulated kinase 1/2 (ERK(1/2)), Akt, and endothelial nitric oxide synthase (eNOS) and increases the level of NO production in a dose- and time-dependent manner. Furthermore, ERK activation and angiogenic sprouting in response to NMB are significantly blocked by the MEK inhibitor. Inhibition of phosphatidylinositol 3-kinase (PI3K) suppresses the NMB-stimulated tubular formation of HUVECs, along with reduction in the phosphorylation of Akt and eNOS. Taken together, these results indicate that NMB is a novel angiogenic peptide, and its angiogenic activity is mediated by activating the MEK/ERK- and PI3K/Akt/eNOS-dependent pathways. This study suggests that NMB may play important roles in mediating a variety of pathophysiological angiogenesis.
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Derangements in endothelial cell-to-cell junctions involved in the pathogenesis of hypercholesterolemia-induced erectile dysfunction.
J Sex Med
PUBLISHED: 04-23-2009
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Endothelial cell-to-cell junctions are crucial for vascular formation, networking, and remodeling of blood vessels as well as for inducing and integrating intracellular signals.
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Neurovascular effects of CD47 signaling: promotion of cell death, inflammation, and suppression of angiogenesis in brain endothelial cells in vitro.
J. Neurosci. Res.
PUBLISHED: 04-11-2009
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The concept of the neurovascular unit emphasizes that common signals and substrates underlie the physiology and pathophysiology of neuronal and endothelial compartments in brain. Recent data suggest that activation of the integrin-associated protein CD47 promotes neuronal cell death. Is it possible that CD47 may also negatively affect cerebral endothelial cells? Exposure of wild-type primary mouse cerebral endothelial cells to the CD47 ligand thrombospondin 1 (TSP-1) induced an increasing amount of cell death, whereas cytotoxicity was significantly decreased in cerebral endothelial cells derived from CD47 knockout mice. The specific CD47-activating peptide, 4N1K, similarly induced cell death in human brain microvascular endothelial cells. Promotion of inflammation was also involved because lower TSP-1 was able to up-regulate the adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. Finally, CD47 signaling may suppress angiogenesis because 4N1K significantly inhibited endothelial cell migration and tube formation in vitro. We conclude that CD47 signaling can negatively affect the viability and function of cerebral endothelial cells, further supporting the notion that CD47 may be a potential neurovascular target for stroke and brain injury.
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Role of oxidative stress and caspase 3 in CD47-mediated neuronal cell death.
J. Neurochem.
PUBLISHED: 04-09-2009
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CD47 or integrin-associated protein promotes cell death in blood and tumor cells. Recently, CD47 signaling has been identified in neurons as well. In this study, we investigated the role of CD47 in neuronal cell death. Exposure of primary mouse cortical neurons to the CD47 ligand thrombospondin-1 or the specific CD47-activating peptide 4N1K induced cell death. Activation of CD47 elevated levels of active caspase 3 and increased the generation of reactive oxygen species (ROS) in a time-dependent manner. Both ROS scavengers and caspase inhibitors attenuated cell death. But ROS scavenging did not reduce the activation of caspase 3, and combination treatments with a caspase inhibitor plus free radical scavenger did not yield additive protection. Taken together, these data suggest that parallel and redundant pathways of oxidative stress and caspase-mediated cell death are involved. We conclude that CD47 mediates neuronal cell death through caspase-dependent and caspase-independent pathways.
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Neuregulin-1 signaling in brain endothelial cells.
J. Cereb. Blood Flow Metab.
PUBLISHED: 01-31-2009
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Neuregulin-1 (NRG1) signaling has multiple functions in neurons and glia. The data in this study show that NRG1 may also possess significant signaling and cytoprotective properties in human brain microvascular endothelial cells (BMECs). Neuregulin-1 mRNA and protein expression are present in these cells, and NRG1 receptors erbB2 and erbB3 are phosphorylated in response to NRG1. Neuregulin-1 triggers clear biologic responses in BMECs--elevated phospho-Akt levels, increased ring formation in a Matrigel assay, and decreased cell death after oxidative injury with H(2)O(2). These data suggest that NRG1 signaling is functional and cytoprotective in BMECs.
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Angiopoietin-1 reduces vascular endothelial growth factor-induced brain endothelial permeability via upregulation of ZO-2.
Int. J. Mol. Med.
PUBLISHED: 01-17-2009
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Brain microvessels possess barrier structures comprising tight junctions which are critical for the maintenance of central nervous system homeostasis. Brain vascular diseases, such as ischemic stroke damage to blood-brain barrier, increase the vascular permeability, and then lead to vasogenic brain edema. Herein, we examined whether angiopoietin-1 (Ang-1) could regulate zonula occludens-2 (ZO-2) expression and counteract vascular endothelial growth factor (VEGF)-induced vascular permeability. When we treated brain microvascular endothelial cells with Ang-1, Ang-1 caused a time- and dose-dependent increase of ZO-2 and down-regulation in endothelial permeability. VEGF, one of the key regulators of ischemia-induced vascular permeability, increased endothelial cell permeability in vitro, whereas, Ang-1 reversed this VEGF effect by up-regulating ZO-2 expression. Additionally, the recovery effect of Ang-1 on permeability was strongly blocked by siRNA against ZO-2. Collectively, our results suggest that Ang-1 shows anti-permeability activity through up-regulation of ZO-2.
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Hypoxic priming of mESCs accelerates vascular-lineage differentiation through HIF1-mediated inverse regulation of Oct4 and VEGF.
EMBO Mol Med
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Hypoxic microenvironment plays an important role in determining stem cell fates. However, it is controversial to which direction between self-renewal and differentiation the hypoxia drives the stem cells. Here, we investigated whether a short exposure to hypoxia (termed hypoxic-priming) efficiently directed and promoted mouse embryonic stem cells (mESCs) to differentiate into vascular-lineage. During spontaneous differentiation of embryoid bodies (EBs), hypoxic region was observed inside EB spheroids even under normoxic conditions. Indeed, hypoxia-primed EBs more efficiently differentiated into cells of vascular-lineage, than normoxic EBs did. We found that hypoxia suppressed Oct4 expression via direct binding of HIF-1 to reverse hypoxia-responsive elements (rHREs) in the Oct4 promoter. Furthermore, vascular endothelial growth factor (VEGF) was highly upregulated in hypoxia-primed EBs, which differentiated towards endothelial cells in the absence of exogenous VEGF. Interestingly, this differentiation was abolished by the HIF-1 or VEGF blocking. In vivo transplantation of hypoxia-primed EBs into mice ischemic limb elicited enhanced vessel differentiation. Collectively, our findings identify that hypoxia enhanced ESC differentiation by HIF-1-mediated inverse regulation of Oct4 and VEGF, which is a novel pathway to promote vascular-lineage differentiation.
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The radiosensitivity of endothelial cells isolated from human breast cancer and normal tissue in vitro.
Microvasc. Res.
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We developed a novel method for harvesting endothelial cells from blood vessels of freshly obtained cancer and adjacent normal tissue of human breast, and compared the response of the cancer-derived endothelial cells (CECs) and normal tissue-derived endothelial cells (NECs) to ionizing radiation. In brief, when tissues were embedded in Matrigel and cultured in endothelial cell culture medium (ECM) containing growth factors, endothelial cells grew out of the tissues. The endothelial cells were harvested and cultured as monolayer cells in plates coated with gelatin, and the cells of 2nd-5th passages were used for experiments. Both CECs and NECs expressed almost the same levels of surface markers CD31, CD105 and TEM-8 (tumor endothelial marker-8), which are known to be expressed in angiogenic endothelial cells, i.e., mitotically active endothelial cells. Furthermore, both CECs and NECs were able to migrate into experimental wound in the monolayer culture, and also to form capillary-like tubes on Matrigel-coated plates. However, the radiation-induced suppressions of migration and capillary-like tube formations were greater for CECs than NECs from the same patients. In addition, in vitro clonogenic survival assays demonstrated that CECs were far more radiosensitive than NECs. In summary, we have developed a simple and efficient new method for isolating endothelial cells from cancer and normal tissue, and demonstrated for the first time that endothelial cells of human breast cancer are significantly more radiosensitive than their normal counterparts from the same patients.
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Matrigel-based sprouting endothelial cell culture system from mouse corpus cavernosum is potentially useful for the study of endothelial and erectile dysfunction related to high-glucose exposure.
J Sex Med
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A proper cavernous endothelial cell culture system would be advantageous for the study of the pathophysiologic mechanisms involved in endothelial dysfunction and erectile dysfunction (ED).
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Gene therapy with an erythropoietin enhancer-mediated, hypoxia-inducible gene expression system in the corpus cavernosum of mice with high-cholesterol diet-induced erectile dysfunction.
J. Androl.
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Cavernous hypoxia is an important factor in the pathogenesis of vasculogenic erectile dysfunction (ED). Therefore, the hypoxia-inducible gene expression system can be exploited as gene therapy for vasculogenic ED. This study was undertaken to examine the effectiveness of a hypoxia-inducible gene expression system, namely, the RTP801 promoter or the erythropoietin enhancer, in a mouse model of hypercholesterolemic ED in vivo and in primary cultured mouse cavernous endothelial cells in vitro. Two-month-old male C57BL/6 mice were fed a diet containing 4% cholesterol and 1% cholic acid, and age-matched control animals were fed a normal diet for 3 months. Mouse cavernous endothelial cells were isolated and cultured under normoxic or hypoxic conditions. After treatment of animals or endothelial cells with pSV-Luc, pRTP801-Luc, or pEpo-SV-Luc vector, gene expression was evaluated by luciferase assay, and the gene expression area was evaluated by immunohistochemistry. Plasmids pRTP801-Luc and pEpo-SV-Luc induced gene expression significantly in the hypercholesterolemic mice and in cavernous endothelial cells under hypoxia, and the highest gene expression was noted in the group treated with pEpo-SV-Luc. Gene expression was higher for more than 7 days in the hypercholesterolemic mice injected with pEpo-SV-Luc than in mice injected with pSV-Luc. As shown by immunohistochemistry, the gene expression area was also greater in the pEpo-SV-Luc group than in the pSV-Luc group, but the difference was not as great as that in luciferase activity. The hypoxia-specific gene expression system could be a valuable tool for facilitating gene delivery into ischemic corpus cavernosum tissue resulting from vascular causes.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.