Faculty Opinions recommendation of Bone morphogenic protein antagonists are coexpressed with bone morphogenic protein 4 in endothelial cells exposed to unstable flow in vitro in mouse aortas and in human coronary arteries: role of bone morphogenic protein antagonists in inflammation and atherosclerosis.

AbstractPlacenta growth factor (PlGF) is a pro-inflammatory angiogenic mediator that promotes many pathologies including diabetic complications and atherosclerosis. Widespread endothelial dysfunction precedes the onset of these conditions. As very little is known of the mechanism(s) controlling PlGF expression in pathology we investigated the role of hyperglycaemia in the regulation of PlGF production in endothelial cells. Hyperglycaemia stimulated PlGF secretion in cultured primary endothelial cells, which was suppressed by IGF-1-mediated PI3K/Akt activation. Inhibition of PI3K activity resulted in significant PlGF mRNA up-regulation and protein secretion. Similarly, loss or inhibition of Akt activity significantly increased basal PlGF expression and prevented any further PlGF secretion in hyperglycaemia. Conversely, constitutive Akt activation blocked PlGF secretion irrespective of upstream PI3K activity demonstrating that Akt is a central regulator of PlGF expression. Knock-down of the Forkhead box O-1 (FOXO1) transcription factor, which is negatively regulated by Akt, suppressed both basal and hyperglycaemia-induced PlGF secretion, whilst FOXO1 gain-of-function up-regulated PlGF in vitro and in vivo. FOXO1 association to a FOXO binding sequence identified in the PlGF promoter also increased in hyperglycaemia. This study identifies the PI3K/Akt/FOXO1 signalling axis as a key regulator of PlGF expression and unifying pathway by which PlGF may contribute to common disorders characterised by endothelial dysfunction, providing a target for therapy.

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A tumor-promoting role for soluble TβRIII in glioblastoma

Molecular and Cellular Biochemistry ◽

10.1007/s11010-021-04128-y ◽

2021 ◽

Author(s):

Isabel Burghardt ◽

Judith Johanna Schroeder ◽

Tobias Weiss ◽

Dorothee Gramatzki ◽

Michael Weller

Keyword(s):

Endothelial Cells ◽

Ex Vivo ◽

Microvascular Endothelial Cells ◽

Smad2 Phosphorylation ◽

Cell Gene Expression ◽

Microvascular Endothelial ◽

Cell Gene ◽

Mouse Glioma

Abstract Purpose Members of the transforming growth factor (TGF)-β superfamily play a key role in the regulation of the malignant phenotype of glioblastoma by promoting invasiveness, angiogenesis, immunosuppression, and maintaining stem cell-like properties. Betaglycan, a TGF-β coreceptor also known as TGF-β receptor III (TβRIII), interacts with members of the TGF-β superfamily and acts as membrane-associated or shed molecule. Shed, soluble TβRIII (sTβRIII) is produced upon ectodomain cleavage of the membrane-bound form. Elucidating the role of TβRIII may improve our understanding of TGF-β pathway activity in glioblastoma Methods Protein levels of TβRIII were determined by immunohistochemical analyses and ex vivo single-cell gene expression profiling of glioblastoma tissue respectively. In vitro, TβRIII levels were assessed investigating long-term glioma cell lines (LTCs), cultured human brain-derived microvascular endothelial cells (hCMECs), glioblastoma-derived microvascular endothelial cells, and glioma-initiating cell lines (GICs). The impact of TβRIII on TGF-β signaling was investigated, and results were validated in a xenograft mouse glioma model Results Immunohistochemistry and ex vivo single-cell gene expression profiling of glioblastoma tissue showed that TβRIII was expressed in the tumor tissue, predominantly in the vascular compartment. We confirmed this pattern of TβRIII expression in vitro. Specifically, we detected sTβRIII in glioblastoma-derived microvascular endothelial cells. STβRIII facilitated TGF-β-induced Smad2 phosphorylation in vitro and overexpression of sTβRIII in a xenograft mouse glioma model led to increased levels of Smad2 phosphorylation, increased tumor volume, and decreased survival Conclusions These data shed light on the potential tumor-promoting role of extracellular shed TβRIII which may be released by glioblastoma endothelium with high sTβRIII levels.

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Abstract WMP31: Dedifferentiation of Smooth Muscle Cells and its Potential Contribution to Pathogenesis of Intracranial Aneurysms

Stroke ◽

10.1161/str.51.suppl_1.wmp31 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Mieko Oka ◽

Nobuhiko Ohno ◽

Takakazu Kawamata ◽

Tomohiro Aoki

Keyword(s):

Endothelial Cells ◽

Smooth Muscle ◽

Smooth Muscle Cells ◽

Inflammatory Responses ◽

Muscle Cells ◽

Inflammatory Factors ◽

Potential Contribution ◽

Electron Microscopic

Introduction: Intracranial aneurysm (IA) affects 1 to 5 % in general public and becomes the primary cause of subarachnoid hemorrhage, the most severe form of stroke. However, currently, no drug therapy is available for IAs to prevent progression and rupture of lesions. Elucidation of mechanisms underlying the disease is thus mandatory. Considering the important role of vascular smooth muscle cells (SMCs) in the maintenance of stiffness of arterial walls and also in the pathogenesis of atherosclerosis via mediating inflammatory responses, we in the present study analyzed morphological or phenotypical changes of SMCs during the disease development in the lesions. Methods: We subjected rats to an IA model in which lesions are induced by increase of hemodynamic force loading on intracranial arterial bifurcations and performed histopathological analyses of induced lesions including the electron microscopic examination. We then immunostained specimens from induced lesions to explore factors responsible for dedifferentiation or migration of SMCs. In vitro study was also done to examine effect of some candidate factors on dedifferentiation or migration of cultured SMCs. Results: We first found the accumulation of SMCs underneath the endothelial cell layer mainly at the neck portion of the lesion. These cells was positive for the embryonic form of myosin heavy chain, a marker for the dedifferentiated SMCs, and the expression of pro-inflammatory factors like TNF-α. In immunostaining to explore the potential factor regulating the dedifferentiation of SMCs, we found that Platelet-derived growth factor-BB (PDGF-BB) was expressed in endothelial cells at the neck portion of IA walls. Consistently, recombinant PDGF-BB could promote the dedifferentiate of SMCs and chemo-attracted them in in vitro. Finally, in the stenosis model of the carotid artery, PDGF-BB expression was induced in endothelial cells in which high wall shear stress was loaded and the dedifferentiation of SMCs occurred there. Conclusions: The findings from the present study imply the role of dedifferentiated SMCs partially recruited by PDGF-BB from endothelial cells in the formation of inflammatory microenvironment at the neck portion of IA walls, leading to the progression of the disease.

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Metformin-stimulated AMPK-α1 promotes microvascular repair in acute lung injury

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00173.2013 ◽

2013 ◽

Vol 305 (11) ◽

pp. L844-L855 ◽

Cited By ~ 47

Author(s):

Ming-Yuan Jian ◽

Mikhail F. Alexeyev ◽

Paul E. Wolkowicz ◽

Jaroslaw W. Zmijewski ◽

Judy R. Creighton

Keyword(s):

Endothelial Cells ◽

Acute Lung Injury ◽

Lung Injury ◽

Ex Vivo ◽

Endothelial Permeability ◽

Beneficial Effects ◽

Isolated Lung

Acute lung injury secondary to sepsis is a leading cause of mortality in sepsis-related death. Present therapies are not effective in reversing endothelial cell dysfunction, which plays a key role in increased vascular permeability and compromised lung function. AMP-activated protein kinase (AMPK) is a molecular sensor important for detection and mediation of cellular adaptations to vascular disruptive stimuli. In this study, we sought to determine the role of AMPK in resolving increased endothelial permeability in the sepsis-injured lung. AMPK function was determined in vivo using a rat model of endotoxin-induced lung injury, ex vivo using the isolated lung, and in vitro using cultured rat pulmonary microvascular endothelial cells (PMVECs). AMPK stimulation using N1-(α-d-ribofuranosyl)-5-aminoimidizole-4-carboxamide or metformin decreased the LPS-induced increase in permeability, as determined by filtration coefficient ( Kf) measurements, and resolved edema as indicated by decreased wet-to-dry ratios. The role of AMPK in the endothelial response to LPS was determined by shRNA designed to decrease expression of the AMPK-α1 isoform in capillary endothelial cells. Permeability, wounding, and barrier resistance assays using PMVECs identified AMPK-α1 as the molecule responsible for the beneficial effects of AMPK in the lung. Our findings provide novel evidence for AMPK-α1 as a vascular repair mechanism important in the pulmonary response to sepsis and identify a role for metformin treatment in the management of capillary injury.

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The recombinant lectin-like domain of thrombomodulin inhibits angiogenesis through interaction with Lewis Y antigen

Blood ◽

10.1182/blood-2011-08-376038 ◽

2012 ◽

Vol 119 (5) ◽

pp. 1302-1313 ◽

Cited By ~ 31

Author(s):

Cheng-Hsiang Kuo ◽

Po-Ku Chen ◽

Bi-Ing Chang ◽

Meng-Chen Sung ◽

Chung-Sheng Shi ◽

...

Keyword(s):

Endothelial Cells ◽

Egf Receptor ◽

Tube Formation ◽

Endothelial Tube Formation ◽

A Cell ◽

Lewis Y ◽

Tm Domain

AbstractLewis Y Ag (LeY) is a cell-surface tetrasaccharide that participates in angiogenesis. Recently, we demonstrated that LeY is a specific ligand of the recombinant lectin-like domain of thrombomodulin (TM). However, the biologic function of interaction between LeY and TM in endothelial cells has never been investigated. Therefore, the role of LeY in tube formation and the role of the recombinant lectin-like domain of TM—TM domain 1 (rTMD1)—in antiangiogenesis were investigated. The recombinant TM ectodomain exhibited lower angiogenic activity than did the recombinant TM domains 2 and 3. rTMD1 interacted with soluble LeY and membrane-bound LeY and inhibited soluble LeY-mediated chemotaxis of endothelial cells. LeY was highly expressed on membrane ruffles and protrusions during tube formation on Matrigel. Blockade of LeY with rTMD1 or Ab against LeY inhibited endothelial tube formation in vitro. Epidermal growth factor (EGF) receptor in HUVECs was LeY modified. rTMD1 inhibited EGF receptor signaling, chemotaxis, and tube formation in vitro, and EGF-mediated angiogenesis and tumor angiogenesis in vivo. We concluded that LeY is involved in vascular endothelial tube formation and rTMD1 inhibits angiogenesis via interaction with LeY. Administration of rTMD1 or recombinant adeno-associated virus vector carrying TMD1 could be a promising antiangiogenesis strategy.

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Role of endothelial cells in regulating hemoglobin-induced changes in lymphatic pumping

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1992.263.6.h1880 ◽

1992 ◽

Vol 263 (6) ◽

pp. H1880-H1887 ◽

Cited By ~ 1

Author(s):

R. M. Elias ◽

J. Eisenhoffer ◽

M. G. Johnston

Keyword(s):

Endothelial Cells ◽

Smooth Muscle ◽

Inhibitory Effect ◽

Direct Inhibitory Effect ◽

Induced Changes ◽

Lymphatic Pumping ◽

Pumping Activity

Studies with a sheep isolated duct preparation in vivo demonstrated that the route of administration of hemoglobin was important in demonstrating its inhibitory effect on lymphatic pumping. With autologous oxyhemoglobin administered intravenously (final plasma concentration 5 x 10(-5) M), pumping was not inhibited. However, the addition of oxyhemoglobin (5 x 10(-5) M) into the reservoir (lumen of the duct) resulted in > 95% inhibition of pumping. The extraluminal administration of oxyhemoglobin (10(-5) M) to bovine mesenteric lymphatics in vitro resulted in a 40% inhibition of pumping, whereas the introduction of oxyhemoglobin (10(-5) M) into the lumen of the vessels suppressed pumping 95%. In vessels mechanically denuded of endothelium, intraluminal oxyhemoglobin inhibited pumping 50%. These results suggested that oxyhemoglobin depressed pumping through an effect on both smooth muscle and endothelium. Once pumping was inhibited with oxyhemoglobin administration, stimulation of the duct with elevations in transmural pressure restored pumping activity when endothelial cells were present. However, in the absence of endothelium, pumping decreased with increases in distending pressures. We conclude that oxyhemoglobin has a direct inhibitory effect on lymphatic smooth muscle. The ability of oxyhemoglobin to alter the pressure range over which the lymph pump operates appears to be dependent on an intact endothelium.

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Targeting HIF2α-ARNT hetero-dimerisation as a novel therapeutic strategy for Pulmonary Arterial Hypertension

European Respiratory Journal ◽

10.1183/13993003.02061-2019 ◽

2020 ◽

pp. 1902061

Author(s):

David Macias ◽

Stephen Moore ◽

Alexi Crosby ◽

Mark Southwood ◽

Xinlin Du ◽

...

Keyword(s):

Endothelial Cells ◽

Pulmonary Arterial Hypertension ◽

Arterial Hypertension ◽

Target Genes ◽

Right Heart Failure ◽

Pulmonary Vasculature ◽

Pulmonary Arterial ◽

The Impact

Pulmonary Arterial Hypertension (PAH) is a destructive disease of the pulmonary vasculature often leading to right heart failure and death. Current therapeutic intervention strategies only slow disease progression. The role of aberrant HIF2α stability and function in the initiation and development of pulmonary hypertension (PH) has been an area of intense interest for nearly two decades.Here we determine the effect of a novel HIF2α inhibitor (PT2567) on PH disease initiation and progression, using two pre-clinical models of PH. Haemodynamic measurements were performed followed by collection of heart, lung and blood for pathological, gene expression and biochemical analysis. Blood outgrowth endothelial cells from IPAH patients were used to determine the impact of HIF2α-inhibition on endothelial function.Global inhibition of HIF2a reduced pulmonary vascular haemodynamics and pulmonary vascular remodelling in both su5416/hypoxia prevention and intervention models. PT2567 intervention reduced the expression of PH associated target genes in both lung and cardiac tissues and restored plasma nitrite concentration. Treatment of monocrotaline exposed rodents with PT2567 reduced the impact on cardiovascular haemodynamics and promoted a survival advantage. In vitro, loss of HIF2α signalling in human pulmonary arterial endothelial cells suppresses target genes associated with inflammation, and PT2567 reduced the hyper-proliferative phenotype and over-active arginase activity in blood outgrowth endothelial cells from IPAH patients. These data suggest that targeting HIF2α hetero-dimerisation with an orally bioavailable compound could offer a new therapeutic approach for PAH. Future studies are required to determine the role of HIF in the heterogeneous PAH population.

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