Regulation of arginine transport and metabolism by Protein Kinase Cα in endothelial cells: stimulation of CAT2 transporters and arginase activity

Stimulation of Ca2+ mobilization and entry by agonists such as ADP, thrombin, and thromboxane is an early step of platelet activation. Here, we compared the effects of adenosine 3',5'-cyclic monophosphate (cAMP)-elevating prostaglandins, guanosine 3',5'-cyclic monophosphate (cGMP)-elevating nitrovasodilators, membrane-permeant selective activators of cAMP- or cGMP-dependent protein kinases, and physiological endothelium-derived factors on the agonist-evoked Ca2+ mobilization and entry in human platelets. Prostaglandin E1, the prostacyclin analogue Iloprost, the nitric oxide (NO) donor 3-morpholinosydnonimine hydrochloride, and selective activators of cGMP- or cAMP-dependent protein kinase strongly inhibited the agonist-evoked Ca2+ mobilization from intracellular stores and associated late Ca2+ entry but had little effects on the rapid (1st) phase of ADP-evoked Ca2+ entry. During coincubation of platelets with endothelial cells, endothelium-derived factors that were released strongly inhibited platelet agonist-evoked Ca2+ mobilization and only moderately affected the rapid phase of ADP-evoked Ca2+ entry. These effects were partially prevented when endothelial cells were preincubated with cyclooxygenase and/or NO synthase inhibitors. Endothelial cells therefore produce sufficient quantities of labile platelet inhibitors whose effects on the platelet Ca2+ response resemble those observed with selective cAMP- and cGMP-dependent protein kinase activators.

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Pertussis toxin activates l-arginine uptake in pulmonary endothelial cells through downregulation of PKC-α activity

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00236.2003 ◽

2004 ◽

Vol 286 (5) ◽

pp. L974-L983 ◽

Cited By ~ 11

Author(s):

Sergey I. Zharikov ◽

Karina Y. Krotova ◽

Leonid Belayev ◽

Edward R. Block

Keyword(s):

Endothelial Cells ◽

Protein Kinase ◽

Adenylate Cyclase ◽

Pertussis Toxin ◽

Term Treatment ◽

No Production ◽

Arginine Transport ◽

Arginine Uptake ◽

Long Term Treatment

Pertussis toxin (PTX) induces activation of l-arginine transport in pulmonary artery endothelial cells (PAEC). The effects of PTX on l-arginine transport appeared after 6 h of treatment and reached maximal values after treatment for 12 h. PTX-induced changes in l-arginine transport were not accompanied by changes in expression of cationic amino acid transporter (CAT)-1 protein, the main l-arginine transporter in PAEC. Unlike holotoxin, the β-oligomer-binding subunit of PTX did not affect l-arginine transport in PAEC, suggesting that Gαi ribosylation is an important step in the activation of l-arginine transport by PTX. An activator of adenylate cyclase, forskolin, and an activator of protein kinase A (PKA), Sp-cAMPS, did not affect l-arginine transport in PAEC. In addition, inhibitors of PKA or adenylate cyclase did not change the activating effect of PTX on l-arginine uptake. Long-term treatment with PTX (18 h) induced a 40% decrease in protein kinase C (PKC)-α but did not affect the activities of PKC-ϵ and PKC-ζ in PAEC. An activator of PKC-α, phorbol 12-myristate 13-acetate, abrogated the activation of l-arginine transport in PAEC treated with PTX. Incubation of PTX-treated PAEC with phorbol 12-myristate 13-acetate in combination with an inhibitor of PKC-α (Go 6976) restored the activating effects of PTX on l-arginine uptake, suggesting PTX-induced activation of l-arginine transport is mediated through downregulation of PKC-α. Measurements of nitric oxide (NO) production by PAEC revealed that long-term treatment with PTX induced twofold increases in the amount of NO in PAEC. PTX also increased l-[3H]citrulline production from extracellular l-[3H]arginine without affecting endothelial NO synthase activity. These results demonstrate that PTX increased NO production through activation of l-arginine transport in PAEC.

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Astroglial-mediated phosphorylation of the Na-K-Cl cotransporter in brain microvessel endothelial cells

AJP Cell Physiology ◽

10.1152/ajpcell.1996.271.2.c620 ◽

1996 ◽

Vol 271 (2) ◽

pp. C620-C627 ◽

Cited By ~ 23

Author(s):

D. Sun ◽

M. E. O'Donnell

Keyword(s):

Endothelial Cells ◽

Protein Kinase ◽

Fold Increase ◽

Protein Kinase Inhibitors ◽

Astroglial Cell ◽

Astroglial Cells ◽

Hypertonic Medium ◽

Phosphorylation Level ◽

Microvessel Endothelial Cells ◽

Stimulation Of

Our previous studies have shown that cerebral microvessel endothelial cells (CMEC) express a Na-K-Cl cotransporter and that exposure of CMEC to astroglial cells causes a nearly 2-fold increase in activity of the cotransporter but only 1.5-fold increase in expression of cotransport protein [D. Sun, C. Lytle, and M. E. O'Donnell. Am. J. Physiol. 269 (Cell Physiol. 38): C1506-C1512, 1995]. This finding suggests that the astroglial cell effects may be mediated by mechanisms involving cotransporter activation in addition to increased protein expression. In the present study, we evaluated the role of protein phosphorylation in elevation of CMEC cotransport activity by astroglial cells and extracellular hypertonicity. We also examined the effects of protein phosphatase and protein kinase inhibitors on both cotransporter activity and phosphorylation in CMEC. The phosphorylation level of Na-K-Cl cotransport protein was quantitatively evaluated by immunoprecipitation analysis with the use of a monoclonal antibody to the cotransporter after 32P labeling of cultured CMEC. Activity of the cotransporter was assessed as bumetanide-sensitive K influx. We found that the phosphatase inhibitors calyculin A and okadaic acid significantly increased both cotransport activity and phosphorylation of cotransport protein. Activity and phosphorylation level of the cotransporter were also markedly increased by exposing the cells to astroglial cell-conditioned or hypertonic medium. Moreover, the astroglial-induced stimulation of the CMEC cotransporter was inhibited by the protein kinase inhibitor K-252a. These findings suggest that phosphorylation of cotransport protein plays an important role in regulation of Na-K-Cl cotransport activity and that astroglial-induced elevation of cotransport activity involves both phosphorylation-associated stimulation of cotransport activity and increased expression of the cotransporter protein.

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Protease-activated Receptor-1 Activation of Endothelial Cells Induces Protein Kinase Cα-dependent Phosphorylation of Syntaxin 4 and Munc18c

Journal of Biological Chemistry ◽

10.1074/jbc.m410044200 ◽

2004 ◽

Vol 280 (5) ◽

pp. 3178-3184 ◽

Cited By ~ 73

Author(s):

Jian Fu ◽

Anjaparavanda P. Naren ◽

Xiaopei Gao ◽

Gias U. Ahmmed ◽

Asrar B. Malik

Keyword(s):

Endothelial Cells ◽

Protein Kinase ◽

Protein Kinase Cα ◽

Syntaxin 4 ◽

Protease Activated Receptor 1

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Stimulation of tissue plasminogen activator production by retinoic acid: synergistic effect on protein kinase C-mediated activation

Blood ◽

10.1182/blood.v80.4.981.981 ◽

1992 ◽

Vol 80 (4) ◽

pp. 981-987 ◽

Cited By ~ 1

Author(s):

RD Medh ◽

L Santell ◽

EG Levin

Keyword(s):

Endothelial Cells ◽

Protein Kinase C ◽

Retinoic Acid ◽

Protein Kinase ◽

Hela Cells ◽

Additive Effect ◽

Kinase C ◽

Tissue Plasminogen ◽

Camp Levels ◽

Stimulation Of

Abstract Trans retinoic acid (t-RA) stimulated the production of tissue plasminogen activator (tPA) in HeLa-S3 and human umbilical vein endothelial cells (huvecs) in a dose-dependent manner with maximal release (four to five times control) at 40 nmol/L and 40 mumol/L, respectively. In endothelial cells, the stimulation of tPA production by phorbol 12-myristate 13-acetate (PMA) was potentiated 1.9-fold by 10 mumol/L t-RA, or 1.8 times the additive effect. In HeLa cells, total tPA secretion with 10 nmol/L PMA was increased from 43 ng/mL to 96 ng/mL by 40 nmol/L t-RA, which was two times the additive effect. Higher concentrations of t-RA (400 nmol/L) depressed tPA secretion by itself and also suppressed PMA-induced tPA production by 50%. Histamine and thrombin also synergized with t-RA. t-RA (40 nmol/L) and 10 micrograms/mL histamine or 10 U/mL thrombin combined to induce tPA production 3.4 and 1.3 times the additive effect in HeLa cells. Cyclic adenosine monophosphate (cAMP) levels were not significantly affected by 10 nmol/L to 10 mumol/L t-RA. Nor did 10 nmol/L PMA and 40 nmol/L t- RA together affect cAMP levels, suggesting that t-RA-mediated potentiation of PMA-induced tPA production occurred via a mechanism that was independent of cAMP levels. Downregulation of protein kinase C (PKC) by pretreatment of huvecs with 100 nmol/L PMA completely blocked a secondary response to PMA, but did not have a significant effect on t- RA induction. Pretreatment with 10 mumol/L t-RA, on the other hand, did not significantly affect a secondary stimulus by 100 nmol/L PMA, but completely suppressed a secondary stimulation by 10 mumol/L t-RA alone. These studies suggest that the mechanism mediating t-RA stimulation of tPA production interacts with the PKC pathway, resulting in synergism.

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Lysophosphatidylcholine stimulation of CGMP production in human endothelial cells involves tyrosine kinases, heterotrimeric GTP binding proteins, phosphatidylinositol 3-kinase and protein kinase C

Vascular Pharmacology ◽

10.1016/j.vph.2006.08.374 ◽

2006 ◽

Vol 45 (3) ◽

pp. e142-e143

Author(s):

J.L. Whatmore ◽

O. Konopatskaya ◽

A.C. Shore

Keyword(s):

Endothelial Cells ◽

Protein Kinase C ◽

Protein Kinase ◽

Tyrosine Kinases ◽

Phosphatidylinositol 3 Kinase ◽

Human Endothelial Cells ◽

Cgmp Production ◽

Kinase C ◽

Gtp Binding ◽

Stimulation Of

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The stimulation of arginine transport by TNFα in human endothelial cells depends on NF-κB activation

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/j.bbamem.2004.04.001 ◽

2004 ◽

Vol 1664 (1) ◽

pp. 45-52 ◽

Cited By ~ 16

Author(s):

Rossana Visigalli ◽

Ovidio Bussolati ◽

Roberto Sala ◽

Amelia Barilli ◽

Bianca Maria Rotoli ◽

...

Keyword(s):

Endothelial Cells ◽

Human Endothelial Cells ◽

Arginine Transport ◽

Stimulation Of

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Adrenomedullin 2 activates extracellular-signal-regulated kinase in endothelial cells via a protein kinase C α-independent pathway

F1000Research ◽

10.12688/f1000research.2420.1 ◽

2016 ◽

Vol 5 ◽

pp. 26

Author(s):

Xiaojia Guo ◽

Rong Ju ◽

Charles Cha ◽

Michael Simons

Keyword(s):

Endothelial Cells ◽

Protein Kinase C ◽

Protein Kinase ◽

Ventricular Myocytes ◽

Contractile Function ◽

Knockout Mouse Model ◽

Extracellular Signal Regulated Kinase ◽

Kinase C ◽

Extracellular Signal ◽

Protein Kinase Cα

Adrenomedullin 2 plays diverse physiological roles such as regulating cardiovascular functions and blood pressure. It was reported that adrenomedullin 2 can activate protein kinase C in murine ventricular myocytes to augment cardiomyocyte contractile function. Using a protein kinase Cα knockout mouse model, we show here that adrenomedullin 2 activates extracellular-signal-regulated kinase in a protein kinase Cα-independent mechanism in endothelial cells.

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