scholarly journals Limits of isolation and culture: intact vascular endothelium and BKCa

2009 ◽  
Vol 297 (1) ◽  
pp. H1-H7 ◽  
Author(s):  
Shaun L. Sandow ◽  
T. Hilton Grayson
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
Physiological Role ◽  
Vascular Endothelial ◽  
Experimental Conditions ◽  
Disease States ◽  
Vasoactive Substances ◽  
Channel Expression ◽  
Calcium Activated Potassium Channels ◽  
And Function

The potential physiological role of plasmalemmal large-conductance calcium-activated potassium channels (BKCa) in vascular endothelial cells is controversial. Studies of freshly isolated and cultured vascular endothelial cells provide disparate results, both supporting and refuting a role for BKCa in endothelial function. Most studies using freshly isolated, intact, healthy arteries provide little support for a physiological role for BKCa in the endothelium, although recent work suggests that this may not be the case in diseased vessels. In isolated and cultured vascular endothelial cells, the autocrine action of growth factors, hormones, and vasoactive substances results in phenotypic drift. Such an induced heterogeneity is likely a primary factor accounting for the apparent differences, and often enhanced BKCa expression and function, in isolated and cultured vascular endothelial cells. In a similar manner, heterogeneity in endothelial BKCa expression and function in intact arteries may be representative of normal and disease states, BKCa being absent in normal intact artery endothelium and upregulated in disease where dysfunction induces signals that alter channel expression and function. Indeed, in some intact vessels, there is evidence for the presence of BKCa, such as mRNA and/or specific BK subunits, an observation that is consistent with the potential for rapid upregulation, as may occur in disease. This perspective proposes that the disparity in the results obtained for BKCa expression and function from freshly isolated and cultured vascular endothelial cells is largely due to variability in experimental conditions and, furthermore, that the expression of BKCa in intact artery endothelium is primarily associated with disease. Although answers to physiologically relevant questions may only be available in atypical physiological conditions, such as those of isolation and culture, the limitations of these methods require open and objective recognition.

scholarly journals Osteostat/Tumor Necrosis Factor Superfamily 18 Inhibits Osteoclastogenesis and Is Selectively Expressed by Vascular Endothelial Cells

Endocrinology ◽  
2006 ◽  
Vol 147 (1) ◽  
pp. 70-78 ◽  
Author(s):  
Bernardetta Nardelli ◽  
Liubov Zaritskaya ◽  
William McAuliffe ◽  
Yansong Ni ◽  
Clint Lincoln ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
Early Stage ◽  
Osteoclast Differentiation ◽  
Precursor Cells ◽  
In Vitro Assays ◽  
Vascular Endothelial ◽  
Tnf Superfamily ◽  
And Function

Vascular endothelial cells (EC) participate in the process of bone formation through the production of factors regulating osteoclast differentiation and function. In this study, we report the selective expression in primary human microvascular EC of Osteostat/TNF superfamily 18, a ligand of the TNF superfamily. Osteostat protein is detectable in human microvascular EC and is highly up-regulated by IFN-α and IFN-β. Moreover, an anti-Osteostat antibody strongly binds to the vascular endothelium in human tissues, demonstrating that the protein is present in the EC layers surrounding blood vessels. Functional in vitro assays were used to define Osteostat involvement in osteoclastogenesis. Both recombinant and membrane-bound Osteostat inhibit differentiation of osteoclasts from monocytic precursor cells. Osteostat suppresses the early stage of osteoclastogenesis via inhibition of macrophage colony-stimulating factor-induced receptor activator of NF-κB (RANK) expression in the osteoclast precursor cells. This effect appears to be specific for the differentiation pathway of the osteoclast lineage, because Osteostat does not inhibit lipopolysaccharide-induced RANK expression in monocytes and dendritic cells, or activation-induced RANK expression in T cells. These findings demonstrate that Osteostat is a novel regulator of osteoclast generation and substantiate the major role played by the endothelium in bone physiology.

Islet Graft Survival and Function: Concomitant Culture and Transplantation With Vascular Endothelial Cells in Diabetic Rats

2011 ◽  
Vol 92 (11) ◽  
pp. 1208-1214 ◽  
Author(s):  
Xiaoming Pan ◽  
Wujun Xue ◽  
Yang Li ◽  
Xinshun Feng ◽  
Xiaohui Tian ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Graft Survival ◽  
Vascular Endothelial Cells ◽  
Diabetic Rats ◽  
Vascular Endothelial ◽  
Islet Graft ◽  
And Function

scholarly journals Control of proliferation of human vascular endothelial cells. Characterization of the response of human umbilical vein endothelial cells to fibroblast growth factor, epidermal growth factor, and thrombin

1978 ◽  
Vol 77 (3) ◽  
pp. 774-788 ◽  
Author(s):  
D Gospodarowicz ◽  
KD Brown ◽  
CR Birdwell ◽  
BR Zetter
Keyword(s):  
Endothelial Cells ◽  
Growth Factors ◽  
Growth Factor ◽  
Vascular Endothelial Cells ◽  
Umbilical Vein ◽  
Physiological Role ◽  
Cell Types ◽  
Vascular Endothelial ◽  
Human Endothelial Cells ◽  
Epidermal Growth

Because the response of human endothelial cells to growth factors and conditioning agents has broad implications for our understanding of wound healing angiogenesis, and human atherogenesis, we have investigated the responses of these cells to the fibroblast (FGF) and epidermal growth factors (EGF), as well as to the protease thrombin, which has been previously shown to potentiate the growth response of other cell types of FGF and EGF. Because the vascular endothelial cells that form the inner lining of blood vessels may be expected to be exposed to high thrombin concentrations after trauma or in pathological states associated with thrombosis, they are of particular interest with respect to the physiological role of this protease in potentiating cell proliferation. Our results indicate that human vascular endothelial cells respond poorly to either FGF or thrombin alone. In contrast, when cells are maintained in the presence of thrombin, their proliferative response to FGF is greatly increased even in cultures seeded at a density as low as 3 cells/mm2. Human vascular endothelial cells also respond to EGF and thrombin, although their rate of proliferation is much slower than when maintained with FGF and thrombin. In contrast, bovine vascular endothelial cells derived from vascular territories as diverse as the bovine heart, aortic arch, and umbilical vein respond maximally to FGF alone and neither respond to nor bind EGF. Furthermore, the response of bovine vascular endothelial cells to FGF was not potentiated by thrombin, indicating that the set of factors controlling the proliferation of vascular endothelial cells could be species-dependent. The requirement of cultured human vascular endothelial cells for thrombin could explain why the human cells, in contrast to bovine endothelial cells, are so difficult to maintain in tissue culture. Our results demonstrate that by using FGF and thrombin one can develop cultures of human vascular endothelial cells capable of being passage repeatedly while maintaining a high mitotic index. The stock cultures used for these studies have been passed weekly with a split ratio of 1 to 10 and are currently in their 30th passage. These cultures are indistinguishable from earlier passages when examined for the presence of Weibel-Palade bodies or Factor VIII antigen. We conclude that the use of FGF and thrombin can prevent the precocious senescence observed in most human endothelial cells cultures previously described.

P2X4 receptors mediate ATP-induced calcium influx in human vascular endothelial cells

2000 ◽  
Vol 279 (1) ◽  
pp. H285-H292 ◽  
Author(s):  
Kimiko Yamamoto ◽  
Risa Korenaga ◽  
Akira Kamiya ◽  
Zhi Qi ◽  
Masahiro Sokabe ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Molecular Mechanisms ◽  
Calcium Influx ◽  
Vascular Endothelial Cells ◽  
Umbilical Vein ◽  
Vascular Endothelial ◽  
Protein Levels ◽  
Vasoactive Substances ◽  
Intracellular Ca ◽  
P2x4 Receptors

ATP induces Ca2+ influx across the cell membrane and activates release from intracellular Ca2+ pools in vascular endothelial cells (ECs). Ca2+ signaling leads to the modification of a variety of EC functions, including the production of vasoactive substances such as nitric oxide and prostacyclin. However, the molecular mechanisms for ATP-induced Ca2+ influx in ECs have not been thoroughly clarified. Here we demonstrate evidence that a P2X4receptor for an ATP-gated cation channel is predominantly expressed in human ECs and is involved in the ATP-induced Ca2+ influx. Northern blot analysis distinctly showed the expression of P2X4 mRNA in human ECs cultured from the umbilical vein, aorta, pulmonary artery, and skin microvessels. Competitive PCR revealed that P2X4 mRNA expression was much higher in ECs than was the expression of other subtypes, including P2X1, P2X3, P2X5, and P2X7. Treatment of ECs with antisense oligonucleotides designed to target the P2X4 receptor decreased the P2X4 mRNA and protein levels to ∼25% of control levels and markedly prevented the ATP-induced Ca2+ influx.

Revascularization Determines Volume Retention and Gene Expression by Fat Grafts in Mice

2005 ◽  
Vol 230 (10) ◽  
pp. 742-748 ◽  
Author(s):  
Motoko Yamaguchi ◽  
Fumiaki Matsumoto ◽  
Hideaki Bujo ◽  
Manabu Shibasaki ◽  
Kazuo Takahashi ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
Angiogenesis Inhibitor ◽  
Vascular Endothelial ◽  
Fat Grafts ◽  
Expression Of Genes ◽  
Autologous Fat Transplantation ◽  
And Function ◽  
Volume Retention ◽  
Graft Volume

Autologous fat transplantation is a popular and useful technique in plastic and reconstructive surgery. The efficiency and survival of such grafts is predictable in many cases, but there are still issues to be resolved, such as how to improve graft volume retention. To address the issue of volume retention, we studied the effect of revascularization from the recipient on the size and function of adipocytes in fat grafts. Treatment of mice with TNP-470, an angiogenesis inhibitor, reduced blood flow from the recipient into the graft after subcutaneous transplantation of epididymal fat. The weight of transplanted tissues and the size of adipocytes in the grafts were significantly lower in mice treated with TNP-470 (TNP mice) than in control mice. Expression of genes for enzymes related to lipid accumulation was decreased in the grafts of TNP mice compared with control mice. Moreover, the expression of adipocyte-derived angiogenic peptides, VEGF and leptin, was significantly lower in the grafts of TNP mice than in grafts from control animals. The expression of VEGF and leptin by cultured human adipocytes was increased in the presence of conditioned medium from cultured vascular endothelial cells. These results show that the inhibition of the revascularization of fat grafts after transplantation reduces graft volume retention and cellular function. Early and adequate revascularization may be important for both the supply of nutrients and vasoactive interactions between vascular endothelial cells and adipocytes in graft.

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