Development and in vivo validation of tissue-engineered, small-diameter vascular grafts from decellularized aortae of fetal pigs and canine vascular endothelial cells

Globally, increasing mortality from cardiovascular disease has become a problem in recent years. Vascular replacement has been used as a treatment for these diseases, but with blood vessels <6 mm in diameter, existing vascular grafts made of synthetic polymers can be occluded by thrombus formation or intimal hyperplasia. Therefore, the development of new artificial vascular grafts is desirable. In this study, we developed an elastin (EL)–silk fibroin (SF) double-raschel knitted vascular graft 1.5 mm in diameter. Water-soluble EL was prepared from insoluble EL by hydrolysis with oxalic acid. Compared to SF, EL was less likely to adhere to platelets, while vascular endothelial cells were three times more likely to adhere. SF artificial blood vessels densely packed with porous EL were fabricated, and these prevented the leakage of blood from the graft during implantation, while the migration of cells after implantation was promoted. Several kinds of 13C solid-state NMR spectra were observed with the EL–SF grafts in dry and hydrated states. It was noted that the EL molecules in the graft had very high mobility in the hydrated state. The EL–SF grafts were implanted into the abdominal aorta of rats to evaluate their patency and remodeling ability. No adverse reactions, such as bleeding at the time of implantation or disconnection of the sutured ends, were observed in the implanted grafts, and all were patent at the time of extraction. In addition, vascular endothelial cells were present on the graft's luminal surface 2 weeks after implantation. Therefore, we conclude that EL–SF artificial vascular grafts may be useful where small-diameter grafts are required.

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Synthesis and physiological activity of heterodimers comprising different splice forms of vascular endothelial growth factor and placenta growth factor

Biochemical Journal ◽

10.1042/bj3160703 ◽

1996 ◽

Vol 316 (3) ◽

pp. 703-707 ◽

Cited By ~ 34

Author(s):

Ralf BIRKENHÄGER ◽

Bernard SCHNEPPE ◽

Wolfgang RÖCKL ◽

Jörg WILTING ◽

Herbert A. WEICH ◽

...

Keyword(s):

Endothelial Cells ◽

Growth Factor ◽

Vascular Endothelial Cells ◽

Physiological Activity ◽

Expression System ◽

Vascular Endothelial ◽

Placenta Growth Factor ◽

Splice Forms

Vascular endothilial growth factor (VEGF) and placenta growth factor (PIGF) are members of a dimeric-growth-factor family with angiogenic properties. VEGF is a highly potent and specific mitogen for endothelial cells, playing a vital role in angiogenesis in vivo. The role of PIGF is less clear. We expressed the monomeric splice forms VEGF-165, VEGF-121, PIGF-1 and PlGF-2 as unfused genes in Escherichia coli using the pCYTEXP expression system. In vitro dimerization experiments revealed that both homo- and hetero-dimers can be formed from these monomeric proteins. The dimers were tested for their ability to promote capillary growth in vivo and stimulate DNA synthesis in cultured human vascular endothelial cells. Heterodimers comprising different VEGF splice forms, or combinations of VEGF/PlGF splice forms, showed mitogenic activity. The results demonstrate that four different heterodimeric growth factors are likely to have as yet uncharacterized functions in vivo.

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Interaction between vascular endothelial cells and vascular intimal spindle-shaped cells in vitro

Journal of Cell Science ◽

10.1242/jcs.60.1.89 ◽

1983 ◽

Vol 60 (1) ◽

pp. 89-102

Author(s):

D de Bono ◽

C. Green

Keyword(s):

Extracellular Matrix ◽

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Three Dimensional ◽

Vascular Endothelial ◽

Pure Cultures ◽

Species Specific ◽

Endothelial Growth Factor

The interactions between human or bovine vascular endothelial cells and fibroblast-like vascular intimal spindle-shaped cells have been studied in vitro, using species-specific antibodies to identify the different components in mixed cultures. Pure cultures of endothelial cells grow as uniform, nonoverlapping monolayers, but this growth pattern is lost after the addition of spindle cells, probably because the extracellular matrix secreted by the latter causes the endothelial cells to modify the way they are attached to the substrate. The result is a network of tubular aggregates of endothelial cells in a three-dimensional ‘polylayer’ of spindle-shaped cells. On the other hand, endothelial cells added to growth-inhibited cultures of spindle-shaped cells will grow in sheets over the surface of the culture. Human endothelial cells grown in contact with spindle-shaped cells have a reduced requirement for a brain-derived endothelial growth factor. The interactions of endothelial cells and other connective tissue cells in vitro may be relevant to the mechanisms of endothelial growth and blood vessel formation in vivo, and emphasize the potential importance of extracellular matrix in controlling endothelial cell behaviour.

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Function of Tissue-type Plasminogen Activator Releaser on Vascular Endothelial Cells and Thrombolysis In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0037-1613134 ◽

2002 ◽

Vol 87 (06) ◽

pp. 1069-1074 ◽

Cited By ~ 7

Author(s):

Hiroyuki Matsuno ◽

Mikio Hayashi ◽

Koji Horibuchi ◽

Kiyotaka Okada ◽

Hideharu Fukao ◽

...

Keyword(s):

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Tissue Type ◽

Vascular Endothelial ◽

Thrombosis Model ◽

Artery Thrombosis ◽

Type Plasminogen Activator ◽

Thrombolytic Effect ◽

Dose Dependent

SummaryThe effect of monosodium[2-(6-hydroxynaphthalen-2-yl)-6-methylpyrimidin-4-yloxy]acetate dihydrate (JTV-926) on fibrinolysis was investigated in vitro and in vivo. JTV-926 released tissue-type plasminogen activator (t-PA) from human vascular endothelial cells in a dose-dependent manner. The thrombolytic effect of JTV-926 was studied using three animal thrombosis models; a photo-irradiation-induced mouse carotid artery thrombosis model, a photo-irradiation-induced rat femoral artery thrombosis model and a thrombin-induced rat venous thrombosis model. In the mouse thrombosis model, t-PA deficient mice (t-PA−/−mice) and their wild-type (t-PA+/+) were used. JTV-926 was injected as a bolus 30 min after the interruption of blood flow by an occlusion thrombi. Blood flow was continuously monitored for 180 min after intravenous administration of JTV-926 (1 mg/kg). Although the recanalization rate of the occluded artery was 37.5% in t-PA +/+ mice with the vehicle control, it increased to 75% in t-PA+/+ mice after JTV-926 administration. However, when JTV-926 was administrated in t-PA−/−mice, vascular recanalization was not observed in any arteries. In the photo-irradiation-induced rat femoral artery thrombosis model, intra-duodenal administration of JTV-926 induced thrombolysis. Moreover, in the thrombin-induced rat venous thrombosis model, the dose-dependent thrombolysis was also observed by oral administration of JTV-926. It was suggested that JTV-926 revealed a sufficient thrombolytic effect through the absorption from the intestine. Thus, a newly synthesized compound, JTV-926 induced t-PA release from vascular endothelial cells and effective thrombolysis in vivo.

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CYLD regulates angiogenesis by mediating vascular endothelial cell migration

Blood ◽

10.1182/blood-2009-10-248526 ◽

2010 ◽

Vol 115 (20) ◽

pp. 4130-4137 ◽

Cited By ~ 52

Author(s):

Jinmin Gao ◽

Lei Sun ◽

Lihong Huo ◽

Min Liu ◽

Dengwen Li ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Vascular Endothelial Cells ◽

Vascular Endothelial Cell ◽

Tube Formation ◽

Endothelial Cell Migration ◽

Vascular Endothelial

Cylindromatosis (CYLD) is a deubiquitinase that was initially identified as a tumor suppressor and has recently been implicated in diverse normal physiologic processes. In this study, we have investigated the involvement of CYLD in angiogenesis, the formation of new blood vessels from preexisting ones. We find that knockdown of CYLD expression significantly impairs angiogenesis in vitro in both matrigel-based tube formation assay and collagen-based 3-dimensional capillary sprouting assay. Disruption of CYLD also remarkably inhibits angiogenic response in vivo, as evidenced by diminished blood vessel growth into the angioreactors implanted in mice. Mechanistic studies show that CYLD regulates angiogenesis by mediating the spreading and migration of vascular endothelial cells. Silencing of CYLD dramatically decreases microtubule dynamics in endothelial cells and inhibits endothelial cell migration by blocking the polarization process. Furthermore, we identify Rac1 activation as an important factor contributing to the action of CYLD in regulating endothelial cell migration and angiogenesis. Our findings thus uncover a previously unrecognized role for CYLD in the angiogenic process and provide a novel mechanism for Rac1 activation during endothelial cell migration and angiogenesis.

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Matrilysin stimulates DNA synthesis of cultured vascular endothelial cells and induces angiogenesis in vivo

Cancer Letters ◽

10.1016/s0304-3835(01)00634-6 ◽

2001 ◽

Vol 173 (2) ◽

pp. 175-182 ◽

Cited By ~ 31

Author(s):

Itaru Nishizuka ◽

Yasushi Ichikawa ◽

Takashi Ishikawa ◽

Masako Kamiyama ◽

Satoshi Hasegawa ◽

...

Keyword(s):

Endothelial Cells ◽

Dna Synthesis ◽

Vascular Endothelial Cells ◽

Vascular Endothelial

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Ablation of 3-Phosphoinositide-Dependent Protein Kinase 1 (PDK1) in Vascular Endothelial Cells Enhances Insulin Sensitivity by Reducing Visceral Fat and Suppressing Angiogenesis

Molecular Endocrinology ◽

10.1210/me.2010-0412 ◽

2012 ◽

Vol 26 (1) ◽

pp. 95-109 ◽

Cited By ~ 7

Author(s):

Kazuhito Tawaramoto ◽

Ko Kotani ◽

Mitsuru Hashiramoto ◽

Yukiko Kanda ◽

Tomoki Nagare ◽

...

Keyword(s):

Endothelial Cells ◽

Insulin Sensitivity ◽

Protein Kinase ◽

Vascular Endothelial Cells ◽

Whole Body ◽

Vascular Endothelial ◽

Dependent Protein Kinase ◽

Dependent Protein

Abstract The phosphatidylinositol 3-kinase signaling pathway in vascular endothelial cells is important for systemic angiogenesis and glucose metabolism. In this study, we addressed the precise role of the 3-phosphoinositide-dependent protein kinase 1 (PDK1)-regulated signaling network in endothelial cells in vivo, using vascular endothelial PDK1 knockout (VEPDK1KO) mice. Surprisingly, VEPDK1KO mice manifested enhanced glucose tolerance and whole-body insulin sensitivity due to suppression of their hepatic glucose production with no change in either peripheral glucose disposal or even impaired vascular endothelial function at 6 months of age. When mice were fed a standard diet at 6 months of age and a high-fat diet at 3 months of age, hypertrophy of epididymal adipose tissues was inhibited, adiponectin mRNA was significantly increased, and mRNA of MCP1, leptin, and TNFα was decreased in the white adipose tissue of VEPDK1KO mice in comparison with controls. Consequently, both the circulating adiponectin levels and the activity of hepatic AMP-activated protein kinase were significantly increased, subsequently enhancing whole-body insulin sensitivity and energy expenditure with increased hepatic fatty acid oxidation in VEPDK1KO mice. These results provide the first in vivo evidence that lowered angiogenesis through the deletion of PDK1 signaling not only interferes with the growth of adipose tissue but also induces increased energy expenditure due to amelioration of the adipocytokine profile. This demonstrates an unexpected role of PDK1 signaling in endothelial cells on the maintenance of proper glucose homeostasis through the regulation of adipocyte development.

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