Agonist-Stimulated Calcium Entry in Primary Cultures of Human Cerebral Microvascular Endothelial Cells

1999 ◽  
Vol 57 (3) ◽  
pp. 211-226 ◽  
Author(s):  
Li Li ◽  
Brian Bressler ◽  
Rukmini Prameya ◽  
Katerina Dorovini-Zis ◽  
C. Van Breemen
2002 ◽  
Vol 283 (6) ◽  
pp. C1687-C1695 ◽  
Author(s):  
Momoh A. Yakubu ◽  
Charles W. Leffler

We investigated the role of intracellular calcium concentration ([Ca2+]i) in endothelin-1 (ET-1) production, the effects of potential vasospastic agents on [Ca2+]i, and the presence of L-type voltage-dependent Ca2+ channels in cerebral microvascular endothelial cells. Primary cultures of endothelial cells isolated from piglet cerebral microvessels were used. Confluent cells were exposed to either the thromboxane receptor agonist U-46619 (1 μM), 5-hydroxytryptamine (5-HT; 0.1 mM), or lysophosphatidic acid (LPA; 1 μM) alone or after pretreatment with the Ca2+-chelating agent EDTA (100 mM), the L-type Ca2+ channel blocker verapamil (10 μM), or the antagonist of receptor-operated Ca2+ channel SKF-96365 HCl (10 μM) for 15 min. ET-1 production increased from 1.2 (control) to 8.2 (U-46619), 4.9 (5-HT), or 3.9 (LPA) fmol/μg protein, respectively. Such elevated ET-1 biosynthesis was attenuated by verapamil, EDTA, or SKF-96365 HCl. To investigate the presence of L-type voltage-dependent Ca2+channels in endothelial cells, the [Ca2+]isignal was determined fluorometrically by using fura 2-AM. Superfusion of confluent endothelial cells with U-46619, 5-HT, or LPA significantly increased [Ca2+]i. Pretreatment of endothelial cells with high K+ (60 mM) or nifedipine (4 μM) diminished increases in [Ca2+]i induced by the vasoactive agents. These results indicate that 1) elevated [Ca2+]i signals are involved in ET-1 biosynthesis induced by specific spasmogenic agents, 2) the increases in [Ca2+]i induced by the vasoactive agents tested involve receptor as well as L-type voltage-dependent Ca2+ channels, and 3) primary cultures of cerebral microvascular endothelial cells express L-type voltage-dependent Ca2+ channels.


2015 ◽  
Vol 473 (1) ◽  
pp. 1-5 ◽  
Author(s):  
G. Cristina Brailoiu ◽  
Elena Deliu ◽  
Linda M. Console-Bram ◽  
Jonathan Soboloff ◽  
Mary E. Abood ◽  
...  

We provide evidence that cocaine induces sigma-1 receptor-mediated inhibition of store-operated calcium entry (SOCE) in rat brain microvascular endothelial cells. Thus, we reveal sigma-1 receptors as SOCE blockers, adding novel insight regarding endothelial effects of cocaine and endogenous SOCE modulation.


2005 ◽  
Vol 288 (2) ◽  
pp. C272-C281 ◽  
Author(s):  
Hitoshi Ogawa ◽  
David G. Binion ◽  
Jan Heidemann ◽  
Monica Theriot ◽  
Pamela J. Fisher ◽  
...  

Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is a homing receptor preferentially expressed on gut-associated endothelial cells that plays a central role in leukocyte traffic into the mucosal immune compartment. Although the molecular mechanisms underlying endothelial ICAM-1 or E-selectin expression have been intensively investigated, the mechanisms that regulate human MAdCAM-1 expression have not been defined. We report MAdCAM-1 gene and protein expression in primary cultures of human intestinal microvascular endothelial cells (HIMEC) that was not demonstrated in human umbilical vein endothelial cells. Similar to ICAM-1 and E-selectin expression, MAdCAM-1 gene expression in HIMEC was inducible with TNF-α, IL-1β, or LPS activation. However, in striking contrast to ICAM-1 and E-selectin expression, MAdCAM-1 mRNA and protein expression in HIMEC was heavily dependent on culture duration and/or cellular density, suggesting a prominent role for cell-cell interaction among these endothelial cells in the expression of the mucosal addressin. MAdCAM-1 expression was inhibited by both SN-50 (NF-κB inhibitor) and LY-294002 [phosphatidylinositol 3-kinase (PI3-K) inhibitor], whereas ICAM-1 and E-selectin expression was inhibited by SN-50 but not by LY-294002. The Akt phosphorylation by TNF-α or LPS was greater at higher cell density, demonstrating a pattern similar to that of MAdCAM-1 expression. NF-κB activation was not affected by cellular density in HIMEC. MAdCAM-1 expression in human gut endothelial cells is regulated by distinct signaling mechanisms involving both NF-κB and PI3-K/Akt. These data also suggest that PI3-K/Akt is involved in the gut-specific differentiation of HIMEC, which results in expression of the mucosal addressin MAdCAM-1.


2003 ◽  
Vol 284 (1) ◽  
pp. H215-H224 ◽  
Author(s):  
Meetha Medhora ◽  
John Daniels ◽  
Kavita Mundey ◽  
Beate Fisslthaler ◽  
Rudi Busse ◽  
...  

Angiogenesis is one of the most recent physiological functions attributed to products of cytochrome P-450 (CYP450) enymes. To test this at a molecular level in human cells, we used a cloned cDNA for the human endothelial enzyme CYP450 2C9 (CYP2C9) to study growth as well as differentiation of human microvascular endothelial cells from the lung (HMVEC-L). Using adenoviral vectors overexpressing mRNA for CYP2C9, we show that the presence of CYP2C9 doubles thymidine incorporation and stimulates proliferation of primary cultures of endothelial cells compared with Ad5-GFP (control) in 24 h. In addition, there is a significant increase of tube formation in Matrigel after infection of HMVEC-L with Ad5-2C9 than with Ad5-GFP. More interestingly, Ad5-2C9 expressing the antisense product of CYP2C9 (2C9AS) inhibited tube formation compared with both Ad5-GFP as well as the Ad5-2C9 constructs. Finally, we tested the most abundant arachidonic acid metabolite of CYP2C9, 14,15-epoxyeicosatrienoic acid, which induced angiogenesis in vivo when embedded in Matrigel plugs and implanted in adult rats. These data support an important role for CYP2C9 in promoting angiogenesis.


1992 ◽  
Vol 263 (4) ◽  
pp. H1213-H1221 ◽  
Author(s):  
P. M. Renzi ◽  
J. T. Flynn

This study demonstrates that bacterial lipopolysaccharide and lipid A exert a significant effect on eicosanoid formation by primary cultures of microvascular endothelial cells (MECs). Qualitative studies using [14C]-arachidonic acid demonstrated that prostaglandin E2 was the primary eicosanoid formed by MECs after 20 h of treatment with either vehicle or lipopolysaccharide. Significant, dose-dependent productions of PGE2 and prostacyclin, beginning at an endotoxin dose of 0.01 ng/ml, were quantified by radioimmunoassay in supernatants of cells treated for 20 h with lipopolysaccharide or lipid A. This eicosanoid production was inhibited by meclofenamate and cycloheximide and occurred without cellular injury. The time course and kinetics of eicosanoid production in response to endotoxin demonstrate a significant, time-related enhancement. Endotoxin-treated MECs responded to exogenous substrate with augmented PGE2 production, suggesting enhanced prostaglandin endoperoxide synthase activity. These results demonstrate a significant interaction of endotoxin with endothelial cells of microvascular origin that results in an enhanced potential for eicosanoid metabolism. This effect may be mediated in part through induction of prostaglandin endoperoxide synthase.


1998 ◽  
Vol 275 (3) ◽  
pp. G592-G603 ◽  
Author(s):  
David G. Binion ◽  
Sidong Fu ◽  
Kalathur S. Ramanujam ◽  
Yuh Cherng Chai ◽  
Raed A. Dweik ◽  
...  

Increased nitric oxide (NO) production by inducible nitric oxide synthase (iNOS) has been associated with intestinal inflammation, including human inflammatory bowel disease. However, NO can downregulate endothelial activation and leukocyte adhesion, critical steps in the inflammatory response. Using primary cultures of human intestinal microvascular endothelial cells (HIMEC), we determined the role of NO in the regulation of HIMEC activation and interaction with leukocytes. Both nonselective ( N G-monomethyl-l-arginine) and specific ( N-iminoethyl-l-lysine) competitive inhibitors of iNOS significantly increased binding of leukocytes by HIMEC activated with cytokines and lipopolysaccharide. Increased adhesion was reversible with the NOS substratel-arginine and was not observed in human umbilical vein endothelial cells (HUVEC). Activation of HIMEC significantly upregulated HIMEC iNOS expression and NO production. NOS inhibitors did not augment cell adhesion molecule levels in activated HIMEC but did result in sustained increases in intracellular reactive oxygen species. In addition, antioxidant compounds reversed the effect of NOS inhibitors on HIMEC-leukocyte interaction. Taken together, these data suggest that after HIMEC activation, iNOS-derived NO is an endogenous antioxidant, downregulating leukocyte binding and potentially downregulating intestinal inflammation.


2004 ◽  
Vol 286 (6) ◽  
pp. G1059-G1068 ◽  
Author(s):  
Jan Heidemann ◽  
Hitoshi Ogawa ◽  
Parvaneh Rafiee ◽  
Norbert Lügering ◽  
Christian Maaser ◽  
...  

Mice genetically deficient in the chemokine receptor CXCR4 or its ligand stromal cell-derived factor (SDF)-1/CXCL12 die perinatally with marked defects in vascularization of the gastrointestinal tract. The aim of this study was to define the expression and angiogenic functions of microvascular CXCR4 and SDF-1/CXCL12 in the human intestinal tract. Studies of human colonic mucosa in vivo and primary cultures of human intestinal microvascular endothelial cells (HIMEC) in vitro showed that the intestinal microvasculature expresses CXCR4 and its cognate ligand SDF-1/CXCL12. Moreover, SDF-1/CXCL12 stimulation of HIMEC triggers CXCR4-linked G proteins, phosphorylates ERK1/2, and activates proliferative and chemotactic responses. Pharmacological studies indicate SDF-1/CXCL12 evokes HIMEC chemotaxis via activation of ERK1/2 and phosphoinositide 3-kinase signaling pathways. Consistent with chemotaxis and proliferation, endothelial tube formation was inhibited by neutralizing CXCR4 or SDF-1/CXCL12 antibodies, as well as the ERK1/2 inhibitor PD-98059. Taken together, these data demonstrate an important mechanistic role for CXCR4 and SDF-1/CXCL12 in regulating angiogenesis within the human intestinal mucosa.


1994 ◽  
Vol 267 (4) ◽  
pp. L433-L441 ◽  
Author(s):  
J. C. Magee ◽  
A. E. Stone ◽  
K. T. Oldham ◽  
K. S. Guice

Highly pure primary cultures of rat lung microvascular endothelial cells were obtained from peripheral lung tissue using a combination of selective culture strategies. The cells had a characteristic morphology consistent with an endothelial origin and were positive for a number of endothelial cell markers, including uptake of fluorescent acetylated lactate dehydrogenase, binding of the lectin Bandeiraea simplicifolia I, and positive immunofluorescence staining with two endothelial cell monoclonal antibodies. The cells behaved as microvascular endothelial cells using an in vitro angiogenesis assay. This isolation method provides a simple method for culturing the pulmonary microvasculature of the rat and these studies support the idea that endothelial cells from different vessels exhibit phenotypic heterogeneity. This method should prove useful for studying specialized endothelial cell function and differentiation in vitro.


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