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Elferink, Oude; Ronald, P J

doi:10.5117/9789056292362

Cited by 6 publications

(6 citation statements)

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“…Since endothelial cells predominantly express the EDG-1 transcript, S1P is likely to downregulate the activity of adenylate cyclase in endothelial cells. Thus, such S1P-mediated inhibition of cAMP accumulation may positively contribute to cell migration because cAMP is implicated as an inhibitory factor of chemotactic response in various cells (33)(34)(35). This possibility is in part supported by our observation that an activator of adenylate cyclase, folskolin, significantly inhibited S1P-induced HUVEC migration in a dose-dependent manner (36), although the alternation of endothelial cAMP levels upon S1P treatment has yet been determined.…”

Section: Figmentioning

confidence: 85%

Sphingosine 1-Phosphate Stimulates Tyrosine Phosphorylation of Focal Adhesion Kinase and Chemotactic Motility of Endothelial Cells via the Gi Protein-Linked Phospholipase C Pathway

Lee

Kim

et al. 2000

Biochemical and Biophysical Research Communications

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Section: Figmentioning

confidence: 85%

Sphingosine 1-Phosphate Stimulates Tyrosine Phosphorylation of Focal Adhesion Kinase and Chemotactic Motility of Endothelial Cells via the Gi Protein-Linked Phospholipase C Pathway

Lee

Kim

et al. 2000

Biochemical and Biophysical Research Communications

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“…Thimerosal, however, is an exogenous organomercapturial compound that modifies SH residues most likely via S-alkylation (52). If endogenous GSNO had the potential to produce similar modifications of RyR channel activity as thimerosal, a significant enhancement of the CICR process would be expected in response to GSNOinduced endogenous redox modification of the channel protein.…”

Section: Camentioning

confidence: 99%

S-Glutathionylation Decreases Mg2+ Inhibition and S-Nitrosylation Enhances Ca2+ Activation of RyR1 Channels

Aracena-Parks

Pecchi

Donoso

et al. 2003

Journal of Biological Chemistry

117

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We have analyzed the effects of the endogenous redoxactive agents S-nitrosoglutathione and glutathione disulfide, and the NO donor NOR-3, on calcium release kinetics mediated by ryanodine receptor channels. Incubation of triad-enriched sarcoplasmic reticulum vesicles isolated from mammalian skeletal muscle with these three agents elicits different responses. Glutathione disulfide significantly reduces the inhibitory effect of Mg 2؉ without altering Ca 2؉ activation of release kinetics, whereas NOR-3 enhances Ca 2؉ activation of release kinetics without altering Mg 2؉ inhibition. Incubation with S-nitrosoglutathione produces both effects; it significantly enhances Ca 2؉ activation of release kinetics and diminishes the inhibitory effect of Mg 2؉ on this process. Triad incubation with [ 35 S]nitrosoglutathione at pCa 5 promoted 35 S incorporation into 2.5 cysteine residues per channel monomer; this incorporation decreased significantly at pCa 9. These findings indicate that S-nitrosoglutathione supports S-glutathionylation as well as the reported S-nitrosylation of ryanodine receptor channels (Sun, J., Xu, L., Eu, J. P., Stamler, J. S., and Meissner, G. (2003) J. Biol. Chem. 278, 8184 -8189). The combined results suggest that S-glutathionylation of specific cysteine residues can modulate channel inhibition by Mg 2؉ , whereas S-nitrosylation of different cysteines can modulate the activation of the channel by Ca 2؉ . Possible physiological and pathological implications of the activation of skeletal Ca 2؉ release channels by endogenous redox species are discussed. Ca 2ϩ -induced Ca 2ϩ release (CICR) 1 mediated by ryanodine receptors/Ca 2ϩ release channels (RyR channels) has a central role in very dissimilar processes. Among other processes, CICR mediates muscle contraction, neuronal plasticity, and secretion (1-4). Not surprisingly, these Ca 2ϩ release channels are extensively regulated by a variety of endogenous ions and molecules, as well as through interactions with other proteins (3,(5)(6)(7)(8).During the last 15 years, increasing evidence has accumulated supporting redox modulation of RyR channels (for reviews, see Refs. 9 -11). Each of the four homologous 565-kDa protein subunits of the skeletal muscle type 1 ryanodine receptor channel (RyR1 channel) contains 100 cysteine residues (12). In the native channel, ϳ50 of these residues appear to be in the reduced state, and, of these, ϳ10 -12 are highly susceptible to oxidation/modification by exogenous sulfhydryl (SH) reagents (13). Sulfhydryl modification enhances Ca 2ϩ release from skeletal SR vesicles (14 -20) and activates RyR1 channels incorporated in planar lipid bilayers (18,(21)(22)(23)(24)(25)(26). Sulfhydryl modification also increases [ 3 H]ryanodine binding to skeletal SR membranes (18,21,24,27). Highly reactive SH residues of the RyR1 channel protein participate in interactions between homotetrameric channel subunits (24), participate in the formation of high molecular weight complexes with triadin (29, 30), and modulate calmodulin binding to the cha...

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“…Thimerosal is a water-soluble thiosalicylic acid derivative, mainly used as a preservative in vaccines and various chemicals, which is characterized by the presence of an atom of mercury in its structure (20) and has been used to enhance eicosanoid production in cells. It is well known as a sulfhydryl reagent, and it has been hypothesized that thimerosal covalently interacts with sulfhydryl groups present in the active site of target enzymes, including LAT (21), leading to enzyme inactivation.…”

mentioning

confidence: 99%

Effect of Arachidonic Acid Reacylation on Leukotriene Biosynthesis in Human Neutrophils Stimulated with Granulocyte-macrophage Colony-stimulating Factor and Formyl-methionyl-leucyl-phenylalanine

Zarini

Gijón

Folco

et al. 2006

Journal of Biological Chemistry

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Priming of human neutrophils with granulocyte-macrophage colony-stimulating factor (GM-CSF) followed by treatment with formyl-methionyl-leucyl-phenylalanine (fMLP) stimulates cells in a physiologically relevant manner with modest 5-lipoxygenase activation and formation of leukotrienes. However, pretreatment of neutrophils with thimerosal, an organomercury thiosalicylic acid derivative, led to a dramatic increase (>50-fold) in the production of leukotriene B 4 and 5-hydroxyeicosatetraenoic acid, significantly higher than that observed after stimulation with calcium ionophore A23187. Little or no effect was observed with thimerosal alone or in combination with either GM-CSF or fMLP. Elevation of [Ca 2؉ ] i induced by thimerosal in neutrophils stimulated with GM-CSF/ fMLP was similar but more sustained compared with samples where thimerosal was absent. However, [Ca 2؉ ] i was significantly lower compared with calcium ionophore-treated cells, suggesting that a sustained calcium rise was necessary but not sufficient to explain the effects of this compound on the GM-CSF/fMLP-stimulated neutrophil. Thimerosal was found to directly inhibit neutrophil lysophospholipid:acyl-CoA acyltransferase activity at the doses that stimulate leukotriene production, and analysis of lysates from neutrophil preparations stimulated in the presence of thimerosal showed a marked increase in free arachidonic acid, supporting the inhibition of the reincorporation of this fatty acid into the membrane phospholipids as a mechanism of action for this compound. The dramatic increase in production of leukotrienes by neutrophils when a physiological stimulus such as GM-CSF/fMLP is employed in the presence of thimerosal suggests a critical regulatory role of arachidonate reacylation that limits leukotriene biosynthesis in concert with 5-lipoxygenase and cytosolic phospholipase A 2 ␣ activation.Neutrophils play an important role in natural immunity and function to eliminate microbes and dead tissues. They are also a major cell involved in the acute inflammatory response, since they respond rapidly to chemotactic stimuli and can be activated by cytokines produced primarily by macrophages to perform degradative and phagocytic functions. Upon activation at the site of inflammation, they release lysosomal enzymes and neutral proteinases, reactive oxygen species, including H 2 O 2 and O 2 .(1, 2), and metabolites of arachidonic acid (AA), 2 in particular leukotriene B 4 (LTB 4 ) (3). Biosynthesis of leukotrienes involves the release of AA from membrane phospholipids by Ca 2ϩ -dependent cytosolic phospholipase A 2 ␣ (cPLA 2 ␣) (4) and its conversion into 5-hydroperoxyeicosatetraenoic acid and subsequently leukotriene A 4 (LTA 4 ), catalyzed by 5-lipoxygenase (5-LO) (5). LTA 4 is then enzymatically converted to LTB 4 by LTA 4 -hydrolase (6) or to leukotriene C 4 (LTC 4 ) by the addition of a molecule of glutathione through the action of LTC 4 -synthase (7). The site for most of these biochemical events is the perinuclear region (8).Regulation of leukotrie...

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Van gen ... tot genezing

Cited by 6 publications

References 0 publications

Sphingosine 1-Phosphate Stimulates Tyrosine Phosphorylation of Focal Adhesion Kinase and Chemotactic Motility of Endothelial Cells via the Gi Protein-Linked Phospholipase C Pathway

Sphingosine 1-Phosphate Stimulates Tyrosine Phosphorylation of Focal Adhesion Kinase and Chemotactic Motility of Endothelial Cells via the Gi Protein-Linked Phospholipase C Pathway

S-Glutathionylation Decreases Mg2+ Inhibition and S-Nitrosylation Enhances Ca2+ Activation of RyR1 Channels

Effect of Arachidonic Acid Reacylation on Leukotriene Biosynthesis in Human Neutrophils Stimulated with Granulocyte-macrophage Colony-stimulating Factor and Formyl-methionyl-leucyl-phenylalanine

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