Phospholipases and activation of the NADPH oxidase

McPhail, Linda C.; Qualliotine-Mann, Diane; Agwu, David E.; McCall, Charles E.

doi:10.1111/j.1600-0609.1993.tb01611.x

Cited by 39 publications

(5 citation statements)

References 53 publications

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“…How Ac2-26 interferes with the activation of NADPH oxidase is not fully understood. Annexin-1 or Ac2-26 peptide has previously been shown to inhibit phospholipase A2 [49], [50] and phosopholipases are involved in the activation of NADPH oxidase in several cell types [14], [51]. We therefore propose that Ac2-26 may target phospholipase and this then interferes with NADPH oxidase assembly to reduce superoxide generation.…”

Section: Discussionmentioning

confidence: 91%

Annexin Peptide Ac2-26 Suppresses TNFα-Induced Inflammatory Responses via Inhibition of Rac1-Dependent NADPH Oxidase in Human Endothelial Cells

et al. 2013

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The anti-inflammatory peptide annexin-1 binds to formyl peptide receptors (FPR) but little is known about its mechanism of action in the vasculature. Here we investigate the effect of annexin peptide Ac2-26 on NADPH oxidase activity induced by tumour necrosis factor alpha (TNFα) in human endothelial cells. Superoxide release and intracellular reactive oxygen species (ROS) production from NADPH oxidase was measured with lucigenin-enhanced chemiluminescence and 2′,7′-dichlorodihydrofluorescein diacetate, respectively. Expression of NADPH oxidase subunits and intracellular cell adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) were determined by real-time PCR and Western blot analysis. Promoter activity of nuclear factor kappa B (NFκB) was measured by luciferase activity assay. TNFα stimulated NADPH-dependent superoxide release, total ROS formation and expression of ICAM-1and VCAM-1. Pre-treatment with N-terminal peptide of annexin-1 (Ac2-26, 0.5–1.5 µM) reduced all these effects, and the inhibition was blocked by the FPRL-1 antagonist WRW4. Furthermore, TNFα-induced NFκB promoter activity was attenuated by both Ac2-26 and NADPH oxidase inhibitor diphenyliodonium (DPI). Surprisingly, Nox4 gene expression was reduced by TNFα whilst expression of Nox2, p22phox and p67phox remained unchanged. Inhibition of NADPH oxidase activity by either dominant negative Rac1 (N17Rac1) or DPI significantly attenuated TNFα-induced ICAM-1and VCAM-1 expression. Ac2-26 failed to suppress further TNFα-induced expression of ICAM-1 and VCAM-1 in N17Rac1-transfected cells. Thus, Ac2-26 peptide inhibits TNFα-activated, Rac1-dependent NADPH oxidase derived ROS formation, attenuates NFκB pathways and ICAM-1 and VCAM-1 expression in endothelial cells. This suggests that Ac2-26 peptide blocks NADPH oxidase activity and has anti-inflammatory properties in the vasculature which contributes to modulate in reperfusion injury inflammation and vascular disease.

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Section: Discussionmentioning

confidence: 91%

Annexin Peptide Ac2-26 Suppresses TNFα-Induced Inflammatory Responses via Inhibition of Rac1-Dependent NADPH Oxidase in Human Endothelial Cells

et al. 2013

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“…Both phosphoinositides (reviewed in Ref. 80) and PA (36) were proposed as intermediates in the signal transduction path leading from membrane receptors to oxidase assembly.…”

Section: Discussionmentioning

confidence: 99%

Tripartite Chimeras Comprising Functional Domains Derived from the Cytosolic NADPH Oxidase Components p47 , p67 , and Rac1 Elicit Activator-independent Superoxide Production by Phagocyte Membranes

Berdichevsky¹,

Mizrahi²,

Ugolev

et al. 2007

Journal of Biological Chemistry

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The superoxide-generating NADPH oxidase is converted to an active state by the assembly of a membrane-localized cytochrome b 559 with three cytosolic components: p47 phox , p67 phox , and GTPase Rac1 or Rac2. Assembly involves two sets of protein-protein interactions: among cytosolic components and among cytosolic components and cytochrome b 559 within its lipid habitat. We circumvented the need for interactions among cytosolic components by constructing a recombinant tripartite chimera (trimera) consisting of the Phox homology (PX) and Src homology 3 (SH3) domains of p47 phox , the tetratricopeptide repeat and activation domains of p67 phox , and full-length Rac1. Upon addition to phagocyte membrane, the trimera was capable of oxidase activation in vitro in the presence of an anionic amphiphile. The trimera had a higher affinity (lower EC 50 ) for and formed a more stable complex (longer half-life) with cytochrome b 559 compared with the combined individual components, full-length or truncated. Supplementation of membrane with anionic but not neutral phospholipids made activation by the trimera amphiphile-independent. Mutagenesis, truncations, and domain replacements revealed that oxidase activation by the trimera was dependent on the following interactions: 1) interaction with anionic membrane phospholipids via the polybasic stretch at the C terminus of the Rac1 segment; 2) interaction with p22 phox via Trp 193 in the N-terminal SH3 domain of the p47 phox segment, supplementing the electrostatic attraction; and 3) an intrachimeric bond among the p67 phox and Rac1 segments complementary to their physical fusion. The PX domain of the p47 phox segment and the insert domain of the Rac1 segment made only minor contributions to oxidase assembly.Phagocytes produce reactive oxygen radicals, part of their microbicidal arsenal, by means of a tightly regulated enzyme complex commonly referred to as NADPH oxidase. At the origin of all oxygen radicals is the superoxide anion (O 2 . ), generated by the NADPH-derived one-electron reduction of molecular oxygen. The O 2 . -generating NADPH oxidase complex (briefly "oxidase") consists of a membrane-associated flavocytochrome (cytochrome b 559 ) comprising two subunits (gp91 phox and p22 phox ) and four cytosolic components (p47 phox , p67 phox , p40 phox , and small GTPase Rac1 or Rac2) (reviewed in Refs. 1-3). Electron flow from NADPH to oxygen occurs along three redox stations, all of which are located on gp91 phox : the NADPH-binding site, FAD, and two non-identical hemes. It is assumed that initiation of electron flow is the consequence of a conformational change in gp91 phox induced by its interaction with p67 phox . The region in p67 phox presumed to be involved in such interaction is known as the "activation domain" and consists of residues 199 -210 (4). It has been suggested that the roles of p47 phox and Rac are to serve as carriers of p67 phox to the membrane or as membrane anchors for p67 phox to enable the correct juxtaposing of the activation domain on p67 phox t...

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“…Hyperoxia activates lung EC NADPH oxidase, which in part was mediated by ERK and p38 MAPK signaling (156,194 In intact neutrophils, modulation of signal-transduction pathways, initiated by specific receptor-ligand interactions, activate three types of phospholipases: phospholipase A 2 , phospholipase C, and phospholipase D (62,137,146,149,167). Activation of PLA 2 releases arachidonic acid (AA) from the sn-2 position of membrane phospholipids, and its subsequent conversion to oxygenated derivatives by cyclooxygenase =lipoxygenase activates NADPH oxidase activity (40).…”

Section: Regulation Of Endothelial Nadph Oxidase Activationmentioning

confidence: 99%

“…LPA is a naturally occurring bioactive lipid that signals via G proteincoupled LPA receptors in ECs and other cell types (41). Thus, PA generated by the PLD pathway and subsequent metabolism of PA to DAG modulates phagocytic and nonphagocytic NADPH oxidase (42,137,138,152,167,171); however, the molecular mechanism(s) of PA-mediated NADPH oxidase activation is(are) poorly understood. In vitro, PA stimulates phosphorylation of subunits of NADPH oxidase through PAdependent kinases yet to be identified (138,204 …”

Section: Regulation Of Endothelial Nadph Oxidase Activationmentioning

confidence: 99%

Regulation of NADPH Oxidase in Vascular Endothelium: The Role of Phospholipases, Protein Kinases, and Cytoskeletal Proteins

Pendyala¹,

Usatyuk²,

Горшкова³

et al. 2009

Antioxidants & Redox Signaling

110

108

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The generation of reactive oxygen species (ROS) in the vasculature plays a major role in the genesis of endothelial cell (EC) activation and barrier function. Of the several potential sources of ROS in the vasculature, the endothelial NADPH oxidase family of proteins is a major contributor of ROS associated with lung inflammation, ischemia=reperfusion injury, sepsis, hyperoxia, and ventilator-associated lung injury. The NADPH oxidase in lung ECs has most of the components found in phagocytic oxidase, and recent studies show the expression of several homologues of Nox proteins in vascular cells. Activation of NADPH oxidase of nonphagocytic vascular cells is complex and involves assembly of the cytosolic (p47 phox , p67 phox , and Rac1) and membrane-associated components (Noxes and p22 phox ). Signaling pathways leading to NADPH oxidase activation are not completely defined; however, they do appear to involve the cytoskeleton and posttranslation modification of the components regulated by protein kinases, protein phosphatases, and phospholipases. Furthermore, several key components regulating NADPH oxidase recruitment, assembly, and activation are enriched in lipid microdomains to form a functional signaling platform. Future studies on temporal and spatial localization of Nox isoforms will provide new insights into the role of NADPH oxidase-derived ROS in the pathobiology of lung diseases. Antioxid. Redox Signal. 11, 841-860.

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Phospholipases and activation of the NADPH oxidase

Cited by 39 publications

References 53 publications

Annexin Peptide Ac2-26 Suppresses TNFα-Induced Inflammatory Responses via Inhibition of Rac1-Dependent NADPH Oxidase in Human Endothelial Cells

Annexin Peptide Ac2-26 Suppresses TNFα-Induced Inflammatory Responses via Inhibition of Rac1-Dependent NADPH Oxidase in Human Endothelial Cells

Tripartite Chimeras Comprising Functional Domains Derived from the Cytosolic NADPH Oxidase Components p47 , p67 , and Rac1 Elicit Activator-independent Superoxide Production by Phagocyte Membranes

Regulation of NADPH Oxidase in Vascular Endothelium: The Role of Phospholipases, Protein Kinases, and Cytoskeletal Proteins

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