• Journal of Ginseng Research
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• 제40권4호
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• pp.325-333
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• 2016

Background: Ginseng extracts are known to have angiogenic effects. However, to date, only limited information is available on the molecular mechanism underlying the angiogenic effects and the main components of ginseng that exert these effects. Human umbilical-vein endothelial cells (HUVECs) are used as an in vitro model for screening therapeutic agents that promote angiogenesis and wound healing. We recently isolated gintonin, a novel ginseng-derived lysophosphatidic acid (LPA) receptor ligand, from ginseng. LPA plays a key role in angiogenesis and wound healing. Methods: In the present study, we investigated the in vitro effects of gintonin on proliferation, migration, and tube formation of HUVECs, which express endogenous LPA1/3 receptors. Results: Gintonin stimulated proliferation and migration of HUVECs. The LPA1/3 receptor antagonist, Ki16425, short interfering RNA against LPA1 or LPA3 receptor, and the Rho kinase inhibitor, Y-27632, significantly decreased the gintonin-induced proliferation, migration, and tube formation of HUVECs, which indicates the involvement of LPA receptors and Rho kinase activation. Further, gintonin increased the release of vascular endothelial growth factors from HUVECs. The cyclooxygenase-2 inhibitor NS-398, nuclear factor kappa B inhibitor BAY11-7085, and c-Jun N-terminal kinase inhibitor SP600125 blocked the gintonin-induced migration, which shows the involvement of cyclooxygenase-2, nuclear factor kappa B, and c-Jun N-terminal kinase signaling. Conclusion: The gintonin-mediated proliferation, migration, and vascular-endothelial-growth-factor release in HUVECs via LPA-receptor activation may be one of in vitro mechanisms underlying ginsenginduced angiogenic and wound-healing effects.

• 생명과학회지
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• 제14권2호
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• pp.263-268
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• 2004

본 연구에서는 FGF-2를 이용하여 혈관내피세포의 발아와 단백질분해효소의 분비 및 인테그린과의 관계를 관찰하여 다음과 같은 결과를 얻었다. PPAECs 세포의 발아에 미치는 FGF-2의 효과를 조사한 결과, 10 ng/ml에서 약 3.5배 증가되는 등 농도-의존적으로 발아가 증가되었다. MMPs에 대한 enzyme immunoassay결과, MMP-2에서만 약 1.9배의 분비증가가 유도되었다. MMP-1 및 MMP-3는 FGF-2에 의해 유의할만한 분비 증가가 나타나지 않았으며, 특이하게 MMP-3는 FGF-2의 처리 없이도 많은 양이 분비되었고, MMP-9은 0.6∼1.2 ng/$10^{6}$ cells 정도로 분비량이 적었다. FGF-2에 의한 플라스민의 분비증가 여부를 확인한 결과, 10 ng/ml에서 약 2.6배 증가하였으며, MMPs 억제제 및 인테그린 억제제에 의해 유의할만한 감소가 나타났고 플라스민 억제제인 $\alpha$2-antiplasmin에 의해서는 플라스민의 분비가 완전히 억제되었다. 또한, FGF-2 처리에 의해 농도-의존적으로 인테그린 Mac-1의 발현이 증가되었으며, 인테그린 억제제인 IS201를 전처리한 결과, 인테그린 Mac-1의 발현이 완전히 억제되었다. FGF-2에 의한 발아 유도효과는 IS201 처리에 의해 거의 완벽하게 억제되었으며, MMP-2 및 플라스민의 분비도 유의할만하게 감소시켰다. 이상의 결과를 요약하면, FGF-2에 의해 유도된 혈관내피세포의 발아 증가는 MMP-2 및 플라스민의 분비증가와 인테그린 Mac-1의 발현 증가에 의한 것이라 생각된다.

• Archives of Reconstructive Microsurgery
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• 제13권2호
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• pp.101-106
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• 2004

Purpose : This study evaluated the effect of VEGF in the arterial anastomosis by using light and electron microscopy. Marerials and method : Rats underwent femoral arterial end-to-end anastomosis after transection and topical VEGF treatment. The proximal and distal segments of the femoral arteries was drenched with 1 drop of VEGF $(100ng/100{\mu}l/bottle)$. and when half of the repair was finished, the other 1 drop was drenched and then the repair was continued to complete the anastomosis. Gross and histologic characteristics of arterial wall were assessed after 3 days, 1, 3 and 5 weeks. In the control group, normal saline solution instead of VEGF was dropped with the same method in the anastomosis. Results : The histologic findings of the arterial wall were the vascular remodeling with the infiltration of inflammatory cells at early stages and the tissue fibrosis at lately stages in the anastomotic sites of the control and the VEGF-treated groups. The scanning electron microscopic results were; (1) the anastomotic sites were covered by many irregular cells with long cytoplasmic processes at the early stages. (2) After 1 week, endothelial cells started to cover the anastomotic sites. (3) After 3 weeks, the anastomotic sites were partially covered by endothelial cells in the control group. (4) After 5 weeks, the anastomotic sites were completely covered by endothelial cells in the control and VEGF-treated groups. (5) In the VEGF-treated group, the anastomotic site was completely covered by endothelial cells which directed parallel to longitudinal axis of arteries after 3 weeks. Conclusion : Topical VEGF maintained luminal integrity by decreasing fibrosis and increasing re-endothelialization. These findings suggest that topical VEGF may be a promising new strategy to enhance healing and improve the outcome of vascular anastomosis.

• Biomolecules & Therapeutics
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• 제27권5호
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• pp.474-483
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• 2019

Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGF-A-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, ${\beta}$-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.

• 한국약용작물학회지
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• 제15권5호
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• pp.311-314
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• 2007

Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are the most important angiogenic molecules associated with tumor-induced neovascularization. This study was carried out to investigate inhibitory effect of extracts from root of Rehmannia glutinosa LIBOSCHITZ (Rehmannia Radix and Rehmannia Radix Preparata) on endothelial cell proliferation. The methanol extracts from the medicinal herb were fractionated into n-hexane, ethyl acetate, n-butanol and aqueous fractions. Among the four fractions, the n-butanol fraction from R. Radix on exhibited highly effective inhibition (${\approx}79%$ inhibition) on the binding of KDR/Flk-1-Fc to immobilized $VEGF_{165}$ and then ethyl acetate fraction from R. Radix (${\approx}45%$ inhibition) at the concentration of $100\;{\mu}g/ml$. The n-butanol fraction efficiently blocked the VEGF- and bFGF-induced HUVEC proliferation in a dose-dependent manner, but did not affect the growth of HT1080 human fibrosarcoma cells. The n-butanol fraction more efficiently blocked the binding of KDR/Flk-1-Fc to immobilized $VEGF_{165}$ and VEGF- and bFGF-induced human umbilical vein endothelial cell proliferation than the fraction from R. Radix Preparata. Our results suggest that Rehmannia Radix may be used as a candidate for developing anti-angiogenic agent.

• Journal of Korean Neurosurgical Society
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• 제29권12호
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• pp.1584-1591
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• 2000

Objective : Until now, it has been little known about the biological mechanisms associated with the genesis, growth, and rupture of intracranial aneurysm. This study was performed to investigate and understand a part of these mechanisms. Materials and Methods : Immunohistochemical stains for angiogenesis growth factors(basic fibroblast growth factor (bFGF) and vascular endothelial growth factor(VEGF)) and selected vascular wall matrix proteins(alpha smooth muscle actin(${\alpha}SMA$) and collagen Type IV) were performed in fixed sections from a normal circle of Willis artery which was taken from the autopsy specimen as a control vessel and 17 aneurysmal wall specimens which was taken during surgical clipping of aneurysms. The staining intensity and distribution of immunoreactivity to angiogenesis growth factors and selected wall matrix proteins in control vessel and aneurysmal wall were examined and compared with each other. The difference of staining intensity according to the size of aneurysm was also investigated. Results : There was no immunoreactivity to bFGF and VEGF in the control vessel. bFGF immunoreactivity was exhibited in 15 of 17 aneurysm specimens around smooth muscle cells within the media of aneurysm. VEGF immunoreactivity was also exhibited in all aneurysm specimens in patches or diffusely affecting all layers of the aneurysmal wall. The degrees of intensity of bFGF and VEGF immunoexpression were proportionate roughly to the size of aneurysm. Strong immunoexpression of both factors were noticed in large aneurysm. A regularly arranged and defined band of immunoreactivity of ${\alpha}SMA$ was noticed in the media of the control vessel, whereas diffuse, faint, irregularly arranged ${\alpha}SMA$ was noticed in the aneurysmal wall. A regularly defined band of collagen Type IV immunoreactivity was also noticed in the subendothelium of the control vessel, whereas diffuse disorganized immunoreactivity of collagen Type IV was noticed in the entire wall of the aneurysm. Conclusion : These results indicate substantial evidences of abnormal expression of angiogenesis factors and changes of selected vascular wall matrix proteins in the wall of intracranial aneurysm. The unbalanced changes of angiogenesis factors and vascular wall matrix proteins in the wall of aneurysm may be one of the biological mechanisms for the growth and rupture of aneurysm.

• The Korean Journal of Physiology and Pharmacology
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• 제19권1호
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• pp.35-42
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• 2015

In cardiovascular disorders, understanding of endothelial cell (EC) function is essential to elucidate the disease mechanism. Although the mouse model has many advantages for in vivo and in vitro research, efficient procedures for the isolation and propagation of primary mouse EC have been problematic. We describe a high yield process for isolation and in vitro culture of primary EC from mouse arteries (aorta, braches of superior mesenteric artery, and cerebral arteries from the circle of Willis). Mouse arteries were carefully dissected without damage under a light microscope, and small pieces of the vessels were transferred on/in a Matrigel matrix enriched with endothelial growth supplement. Primary cells that proliferated in Matrigel were propagated in advanced DMEM with fetal calf serum or platelet-derived serum, EC growth supplement, and heparin. To improve the purity of the cell culture, we applied shearing stress and anti-fibroblast antibody. EC were characterized by a monolayer cobble stone appearance, positive staining with acetylated low density lipoprotein labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate, RT-PCR using primers for von-Willebrand factor, and determination of the protein level endothelial nitric oxide synthase. Our simple, efficient method would facilitate in vitro functional investigations of EC from mouse vessels.

• 대한의생명과학회지
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• 제11권3호
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• pp.355-363
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• 2005

This study aimed to investigate the cerebroprotective effect of vascular endothelial growth factor (VEGF) on permanent focal cerebral ischemia in Sprague-Dawley rats. Right middle cerebral artery (MCA) was occluded for 6 and 24 hours by an intraluminal monofilament technique. An open cranial window was made on the right parietal bone for determination of continuous changes in regional cerebral blood flow (rCBF) by laser-Doppler flowmetry. The infarct size was morphometrically determined using the 2,3,5-triphenyltetrazolium chloride technique. Brain edema was determined by measuring brain water content. In normal rats, rCBF was significantly increased by intravenous infusion of VEGF for 10 minutes. The VEGF-induced increase in rCBF was significantly inhibited by pretreatment with suramin, a heparin-binding growth factor inhibitor as well as $N^{\omega}-nitro-L-arginine$, a nitric oxide synthase inhibitor. In focal cerebral ischemic rats, the amplitude of decrease in rCBF during ischemic period was significantly less in VEGF-treated group, compared with that in vehicle-treated group. The cerebral infarct size was reduced by VEGF in a dose-dependent manner. The brain edema formation was dose-dependently reduced by VEGF in 24-hour MCA occlusion group but not in 6-hour MCA occlusion group. It is suggested that VEGF not only improves the rCBF during cerebral ischemic period but also reduces the brain edema formation, and thereby exert a protective effect on focal cerebral ischemia in rats.

• Biomolecules & Therapeutics
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• 제24권2호
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• pp.132-139
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• 2016

The endothelial-mesenchymal transition (EndMT) is known to be involved in the transformation of vascular endothelial cells to mesenchymal cells. EndMT has been confirmed that occur in various pathologic conditions. Transforming growth factor ${\beta}1$ (TGF-${\beta}1$) is a potent stimulator of the vascular endothelial to mesenchymal transition (EMT). Aspirin-triggered resolvin D1 (AT-RvD1) has been known to be involved in the resolution of inflammation, but whether it has effects on TGF-${\beta}1$-induced EndMT is not yet clear. Therefore, we investigated the effects of AT-RvD1 on the EndMT of human umbilical vein vascular endothelial cells line (HUVECs). Treatment with TGF-${\beta}1$ reduced the expression of Nrf2 and enhanced the level of F-actin, which is associated with paracellular permeability. The expression of endothelial marker VE-cadherin in HUVEC cells was reduced, and the expression of mesenchymal marker vimentin was enhanced. AT-RvD1 restored the expression of Nrf2 and vimentin and enhanced the expression of VE-cadherin. AT-RvD1 did also affect the migration of HUVEC cells. Inhibitory ${\kappa}B$ kinase 16 (IKK 16), which is known to inhibit the NF-${\kappa}B$ pathway, had an ability to increase the expression of Nrf2 and was associated with the inhibition effect of AT-RvD1 on TGF-${\beta}1$-induced EndMT, but it had no effect on TGF-${\beta}1$-induced EndMT alone. Smad7, which is a key regulator of TGF-${\beta}$/Smads signaling by negative feedback loops, was significantly increased with the treatment of AT-RvD1. These results suggest the possibility that AT-RvD1 suppresses the TGF-${\beta}1$-induced EndMT through increasing the expression of Smad7 and is closely related to oxidative stress.

• Molecules and Cells
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• 제28권1호
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• pp.1-5
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• 2009

Vascular endothelial growth factor (VEGF) is essential for many angiogenic processes both in normal and pathological conditions. However, the signaling pathways involved in VEGF-induced angiogenesis are incompletely understood. The protein kinase D1 (PKD1), a newly described calcium/calmodulin-dependent serine/threonine kinase, has been implicated in cell migration, proliferation and membrane trafficking. Increasing evidence suggests critical roles for PKD1-mediated signaling pathways in endothelial cells, particularly in the regulation of VEGF-induced angiogenesis. Recent studies show that class IIa histone deacetylases (HDACs) are PKD1 substrates and VEGF signal-responsive repressors of myocyte enhancer factor-2 (MEF2) transcriptional activation in endothelial cells. This review provides a guide to PKD1 signaling pathways and the direct downstream targets of PKD1 in VEGF signaling, and suggests important functions of PKD1 in angiogenesis.