Superoxide production from paraquat evoked by exogenous NADPH in pulmonary endothelial cells.
AuthorsTampo Y, Tsukamoto M, Yonaha M
JournalFree Radic Biol Med
PubMed ID10490279
'Superoxide production from paraquat in a pulmonary microvascular endothelial cell (PMEC) suspension was demonstrated using 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyraz in-3-one (MCLA), a chemiluminescence probe, to detect superoxide anions. Increased rates of superoxide production from paraquat, which were sensitive to superoxide dismutase (SOD), required the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) in ... More
A noninvasive fluorimetric procedure for measurement of membrane potential. Quantification of the NADPH oxidase-induced depolarization in activated neutrophils.
AuthorsJankowski A, Grinstein S
JournalJ Biol Chem
PubMed ID10473559
'The electrogenic activity of the NADPH oxidase is associated with depolarization of the plasma membrane in activated neutrophils. The magnitude and consequences of this depolarization, however, remain unknown. Neutrophils are not amenable to electrophysiological determinations of membrane potential by current clamp. Instead, the occurrence of depolarization has been inferred from ... More
Apolipoprotein E inhibits platelet aggregation through the L-arginine:nitric oxide pathway. Implications for vascular disease.
AuthorsRiddell DR, Graham A, Owen JS
JournalJ Biol Chem
PubMed ID8995232
'We have previously reported that plasma apolipoprotein (apo) E-containing high density lipoprotein particles have a potent anti-platelet action, apparently by occupying saturable binding sites in the cell surface. Here we show that purified apoE (10-50 microg/ml), complexed with phospholipid vesicles (dimyristoylphosphatidylcholine, DMPC), suppresses platelet aggregation induced by ADP, epinephrine, or ... More
Reduction of quinonoid dihydrobiopterin to tetrahydrobiopterin by nitric oxide synthase.
AuthorsWitteveen CF, Giovanelli J, Kaufman S
JournalJ Biol Chem
PubMed ID8626754
'Rat cerebellar nitric oxide synthase (NOS) purified from transfected human kidney cells catalyzes an NADPHdependent reduction of quinonoid dihydrobiopterin (qBH2) to tetrahydrobiopterin (BH4). Reduction of qBH2 at 25 microM proceeds at a rate that is comparable with that of the overall reaction (citrulline synthesis) and requires calcium ions and calmodulin ... More
Photocatalytic and free radical interactions of the heterocyclic N-oxide resazurin with NADH, GSH, and Dopa.
AuthorsPrütz WA, Butler J, Land EJ
JournalArch Biochem Biophys
PubMed ID8619609
'Electron donating free radicals NAD(.), (.)CO2(-), MV(.)+, and e(aq)-, generated by pulse radiolysis, reduce resazurin (RNO) with rate constants of 1.9 x 10(9), 2.8 x 10(9), 4.8 x 10(9), and 2.3 x 10(10) M(-1) s(-1), respectively, neutral solution. The semireduced dye (RN(.)-O- disproportionates slowly to RN (resorufin) and RNO. There ... More
Phorbol myristate acetate stimulates the formation of 5-oxo-6,8,11,14-eicosatetraenoic acid by human neutrophils by activating NADPH oxidase.
AuthorsPowell WS, Gravelle F, Gravel S
JournalJ Biol Chem
PubMed ID7929234
'We have shown previously that human neutrophil microsomes contain a highly specific dehydrogenase which, in the presence of NADP+, converts 5S-hydroxy-6,8,11,14-eicosatetraenoic acid (5S-HETE) to its 5-oxo metabolite, 5-oxo-ETE, a potent agonist of these cells. However, intact neutrophils convert 5S-HETE principally to its omega-oxidation product, 5,20-diHETE, and to only small amounts ... More
Kinetics of protoporphyrinogen oxidase inhibition by diphenyleneiodonium derivatives.
AuthorsArnould S, Berthon JL, Hubert C, Dias M, Cibert C, Mornet R, Camadro JM
JournalBiochemistry
PubMed ID9254615
'Protoporphyrinogen oxidase, the last enzyme of the common branch of the heme and chlorophyll pathways in plants, is the molecular target of diphenyl ether-type herbicides. These compounds inhibit the enzyme competitively with respect to the tetrapyrrole substrate, protoporphyrinogen IX. We used the flavinic nature of protoporphyrinogen oxidase to investigate the ... More
The effect of the inhibitor diphenylene iodonium on the superoxide-generating system of neutrophils. Specific labelling of a component polypeptide of the oxidase.
AuthorsCross AR, Jones OT
JournalBiochem J
PubMed ID3800872
NADPH-dependent superoxide production by the solubilized oxidase of neutrophils was inhibited 36% by diphenylene iodonium at a 1:1 stoichiometry with the enzyme flavoprotein content. Addition of diphenylene iodonium strongly inhibited the NADPH-dependent reduction of both FAD and cytochrome b-245 in steady-state kinetic experiments. Incubation of solubilized enzyme with diphenylene [125I]iodonium ... More
Inhibition of O2-. generating oxidase of neutrophils by iodonium biphenyl in a cell free system: effect of the redox state of the oxidase complex.
AuthorsDoussiere J, Vignais PV
JournalBiochem Biophys Res Commun
PubMed ID1847802
The conditions of inhibition of neutrophil O2-. generating oxidase by iodonium biphenyl (IBP) were studied. In a cell free system of oxidase activation consisting of neutrophil membranes and cytosol, GTP-gamma-S, Mg2+ and arachidonic acid, the inhibitory effect of IBP depended on the redox conditions of the medium. Inhibition was observed ... More
Mechanism of cellular 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction.
AuthorsLiu Y, Peterson DA, Kimura H, Schubert D
JournalJ Neurochem
PubMed ID9231715
3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction is one of the most frequently used methods for measuring cell proliferation and neural cytotoxicity. It is widely assumed that MTT is reduced by active mitochondria in living cells. By using isolated mitochondria from rat brain and B12 cells, we indeed found that malate, glutamate, and ... More
Simultaneous detection of free radical release and membrane current during phagocytosis.
AuthorsHolevinsky KO, Nelson DJ
JournalJ Biol Chem
PubMed ID7713941
Stimulation of macrophages induces the "respiratory burst" response which is associated with the generation of superoxide (O2-), a drop in cytoplasmic pH, and a pronounced depolarization of the membrane potential. The purpose of the present studies was to determine whether an increase in O2- was temporally related to changes in ... More
Involvement of reactive oxygen species in cytokine and growth factor induction of c-fos expression in chondrocytes.
AuthorsLo YY, Cruz TF
JournalJ Biol Chem
PubMed ID7744816
The cytokine tumor necrosis factor alpha (TNF alpha) and the growth factor basic fibroblast growth factor (bFGF) are known to induce early response genes such as c-fos and c-jun in various cell types. Activation of AP-1, a heterodimeric complex of Fos and Jun proteins, is required for matrix metalloproteinase production ... More
Evidence for the Saccharomyces cerevisiae ferrireductase system being a multicomponent electron transport chain.
AuthorsLesuisse E, Casteras-Simon M, Labbe P
JournalJ Biol Chem
PubMed ID8662826
We have studied the relationships between in vivo (whole cells) and in vitro (plasma membranes) ferrireductase activity in Saccharomyces cerevisiae. Isolated plasma membranes were enriched in the product of the FRE1 gene and had NADPH dehydrogenase activity that was increased when the cells were grown in iron/copper-deprived medium. The diaphorase ... More
beta-amyloid activates the O-2 forming NADPH oxidase in microglia, monocytes, and neutrophils. A possible inflammatory mechanism of neuronal damage in Alzheimer's disease.
AuthorsBianca VD, Dusi S, Bianchini E, Dal Prà I, Rossi F
JournalJ Biol Chem
PubMed ID10336441
The deposition of beta-amyloid in the brain is the key pathogenetic event in Alzheimer's disease. Among the various mechanisms proposed to explain the neurotoxicity of beta-amyloid deposits, a new one, recently identified in our and other laboratories, suggests that beta-amyloid is indirectly neurotoxic by activating microglia to produce toxic inflammatory ... More
The inhibition by diphenyleneiodonium and its analogues of superoxide generation by macrophages.
AuthorsHancock JT, Jones OT
JournalBiochem J
PubMed ID3036079
Peritoneal macrophages were elicited in rats by using casein as a stimulus; when stimulated with phorbol 12-myristate 13-acetate (PMA) they produced O2.-. Nearly 60% of the total cytochrome b had a low Em,7.0 of -247 mV, typical of the cytochrome b component found in the NADPH-dependent O2(.-)-generating oxidase of neutrophils. ... More
Reactive oxygen species mediate cytokine activation of c-Jun NH2-terminal kinases.
AuthorsLo YY, Wong JM, Cruz TF
JournalJ Biol Chem
PubMed ID8663189
Interleukin 1 (IL-1) and tumor necrosis factor alpha (TNFalpha) are known to induce production of reactive oxygen species (ROS), which have been suggested to act as second messengers. Here we demonstrate that ROS production by bovine chondrocytes upon cytokine stimulation induces c-jun expression. Since c-jun expression is regulated by its ... More
Reactive oxygen species mediate the activation of Akt/protein kinase B by angiotensin II in vascular smooth muscle cells.
AuthorsUshio-Fukai M, Alexander RW, Akers M, Yin Q, Fujio Y, Walsh K, Griendling KK
JournalJ Biol Chem
PubMed ID10428852
Angiotensin II, a hypertrophic/anti-apoptotic hormone, utilizes reactive oxygen species (ROS) as growth-related signaling molecules in vascular smooth muscle cells (VSMCs). Recently, the cell survival protein kinase Akt/protein kinase B (PKB) was proposed to be involved in protein synthesis. Here we show that angiotensin II causes rapid phosphorylation of Akt/PKB (6- ... More
Chemiluminescence of mononuclear cells is enhanced during antigen recognition.
AuthorsTengler RS, Furukawa K, de Weck AL, Maly FE
JournalJ Biolumin Chemilumin
PubMed ID8493886
Stimulation of phagocytes by several cytokines causes superoxide generation and consequently chemiluminescence. Since antigen-activated lymphocytes generate cytokines, we investigated whether antigen recognition by mononuclear cells, which contain both lymphocytes and monocytes, is accompanied by changes in lucigenin-dependent chemiluminescence. Mononuclear cells which underwent antigen-induced proliferation showed a delayed rise in lucigenin-dependent ... More
Studies on the inhibitory mechanism of iodonium compounds with special reference to neutrophil NADPH oxidase.
AuthorsO'Donnell BV, Tew DG, Jones OT, England PJ
JournalBiochem J
PubMed ID8439298
Diphenyleneiodonium (DPI) and its analogues have been previously shown to react via a radical mechanism whereby an electron is abstracted from a nucleophile to form a radical, which then adds back to the nucleophile to form covalent adducts [Banks (1966) Chem. Rev. 66, 243-266]. We propose that the inhibition of ... More
Differential regulation of Ca2+ release-activated Ca2+ influx by heterotrimeric G proteins.
AuthorsXu X, Kitamura K, Lau KS, Muallem S, Miller RT
JournalJ Biol Chem
PubMed ID7493943
The least understood aspect of the agonist-induced Ca2+ signal is the activation and regulation of the Ca2+ release-activated Ca2+ influx (CRAC) across the plasma membrane. To explore the possible role of heterotrimeric G proteins in the various regulatory mechanisms of CRAC, continuous renal epithelial cell lines stably expressing alpha 13 ... More
Inhibition of macrophage and endothelial cell nitric oxide synthase by diphenyleneiodonium and its analogs.
The cofactor requirements of macrophage nitric oxide (NO.) synthase suggest involvement of an NADPH-dependent flavoprotein. This prompted us to test the effect of the flavoprotein inhibitors diphenyleneiodonium (DPI), di-2-thienyliodonium (DTI), and iodoniumdiphenyl (ID) on the NO. synthases of macrophages and endothelium. DPI, DTI, and ID completely inhibited NO. synthesis by ... More
Characterization of a Rac1 signaling pathway to cyclin D(1) expression in airway smooth muscle cells.
AuthorsPage K, Li J, Hodge JA, Liu PT, Vanden Hoek TL, Becker LB, Pestell RG, Rosner MR, Hershenson MB
JournalJ Biol Chem
PubMed ID10419534
We examined the importance of the Rho family GTPase Rac1 for cyclin D(1) promoter transcriptional activation in bovine tracheal myocytes. Overexpression of active Rac1 induced transcription from the cyclin D(1) promoter, whereas platelet-derived growth factor (PDGF)-induced transcription was inhibited by a dominant-negative allele of Rac1, suggesting that Rac1 functions as ... More
Lactosylceramide mediates tumor necrosis factor-alpha-induced intercellular adhesion molecule-1 (ICAM-1) expression and the adhesion of neutrophil in human umbilical vein endothelial cells.
AuthorsBhunia AK, Arai T, Bulkley G, Chatterjee S
JournalJ Biol Chem
PubMed ID9852101
The endothelial expression of adhesion molecules by proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) has been suggested to contribute to the initiation of atherosclerotic plaque formation. Since lactosylceramide (LacCer) accumulates in large quantities in human atherosclerotic plaque, we have explored its role in TNF-alpha-induced expression of intercellular adhesion molecule-1 ... More
Intracellular pH regulation during spreading of human neutrophils.
AuthorsDemaurex N, Downey GP, Waddell TK, Grinstein S
JournalJ Cell Biol
PubMed ID8682873
The regulation of the intracelluar pH (pHi) during spreading of human neutrophils was studied by a combination of fluorescence imaging and video microscopy. Spreading on adhesive substrates caused a rapid and sustained cytosolic alkalinization. This pHi increase was prevented by the omission of external Na+, suggesting that it results from ... More
Inhibition of the catalytic activity of alcohol dehydrogenase by nitric oxide is associated with S nitrosylation and the release of zinc.
AuthorsGergel D, Cederbaum AI
JournalBiochemistry
PubMed ID8973191
Nitric oxide (NO) reacts with the sulfhydryl groups of proteins to form nitroso thiols. Alcohol dehydrogenase (ADH) plays an important role in the metabolism of ethanol. Chronic alcohol administration stimulates NO formation in the liver, and production of NO is increased in alcohol liver injury. The effect of exogenous and ... More
Xanthine oxidase-mediated decomposition of S-nitrosothiols.
AuthorsTrujillo M, Alvarez MN, Peluffo G, Freeman BA, Radi R
JournalJ Biol Chem
PubMed ID9525875
S-Nitrosothiols (RSNO) occur in vivo and have been proposed as nitric oxide (.NO) storage and transport biomolecules. Still, the biochemical mechanisms by which RSNO release .NO in biological systems are not well defined, and in particular, the interactions between reactive oxygen species and RSNO have not been studied. In this ... More
Activation of proton pumping in human neutrophils occurs by exocytosis of vesicles bearing vacuolar-type H+-ATPases.
AuthorsNanda A, Brumell JH, Nordström T, Kjeldsen L, Sengelov H, Borregaard N, Rotstein OD, Grinstein S
JournalJ Biol Chem
PubMed ID8663143
Proton pump activity is not measurable in the plasma membrane of unstimulated neutrophils but becomes readily detectable upon activation by soluble agonists. The mechanism of pump activation was investigated in this report. V-type H+ pump activity, estimated as a bafilomycin A1-sensitive elevation of the cytosolic pH, was stimulated in suspended ... More
Redox-regulated signaling by lactosylceramide in the proliferation of human aortic smooth muscle cells.
AuthorsBhunia AK, Han H, Snowden A, Chatterjee S
JournalJ Biol Chem
PubMed ID9188453
Previously, our laboratory reported that lactosylceramide (LacCer) stimulated human aortic smooth muscle cell proliferation via specific activation of p44 mitogen-activated protein kinase (MAPK) in the p21(ras)/Raf-1/MEK2 pathway and induced expression of the transcription factor c-fos downstream to the p44 MAPK signaling cascade (Bhunia A. K., Han, H., Snowden, A., and ... More