Glutamine plays a role in superoxide production and the expression of p47phox, p22phox and gp91phox in rat neutrophils

2002 ◽  
Vol 103 (4) ◽  
pp. 403-408 ◽  
Author(s):  
Tania Cristina PITHON-CURI ◽  
Adriana C. LEVADA ◽  
Lúcia R. LOPES ◽  
Sonia Q. DOI ◽  
Rui CURI
Keyword(s):  
Amino Acid ◽  
Cytochrome C ◽  
Nadph Oxidase ◽  
Superoxide Anion ◽  
Scintillation Counting ◽  
Superoxide Production ◽  
Glutamine Metabolism ◽  
Nadph Oxidase Complex ◽  
O2 Production

The effect of glutamine on the activity of the NADPH oxidase complex from rat neutrophils was investigated. Superoxide anion (O2-) production was assessed: (1) by scintillation counting by using lucigenin, and (2) by reduction of cytochrome c over 10min. The effects of glutamine and PMA on the expression of the NADPH oxidase components p22phox, gp91phox and p47phox were also determined. Glutamine at 1 and 2mM increased O2- generation in the presence of PMA by 100% and 74% respectively, in neutrophils maintained previously for 3h in medium deprived of this amino acid. DON (6-diazo-5-oxo-l-norleucine), an inhibitor of phosphate-dependent glutaminase and thus of glutamine metabolism, caused a significant decrease in O2- production by neutrophils stimulated with PMA both in the absence (44%) and in the presence (66%) of glutamine. PMA markedly increased the expression of gp91phox, p22phox and p47phox mRNAs. Glutamine (2mM) increased the expression of these three proteins both in the absence and in the presence of PMA. We postulate that glutamine leads to O2- production in neutrophils, probably via the generation of ATP and regulation of the expression of components of NADPH oxidase.

scholarly journals Role of l-amino acid oxidase isolated from Calloselasma rhodostoma venom on neutrophil NADPH oxidase complex activation

Toxicon ◽  
2018 ◽  
Vol 145 ◽  
pp. 48-55 ◽  
Author(s):  
Mauro Valentino Paloschi ◽  
Charles Nunes Boeno ◽  
Jéssica Amaral Lopes ◽  
André Eduardo dos Santos da Rosa ◽  
Weverson Luciano Pires ◽  
...  
Keyword(s):  
Amino Acid ◽  
Nadph Oxidase ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Nadph Oxidase Complex ◽  
Calloselasma Rhodostoma

scholarly journals Crumbs limits oxidase-dependent signaling to maintain epithelial integrity and prevent photoreceptor cell death

2012 ◽  
Vol 198 (6) ◽  
pp. 991-998 ◽  
Author(s):  
François J.-M. Chartier ◽  
Émilie J.-L. Hardy ◽  
Patrick Laprise
Keyword(s):  
Nadph Oxidase ◽  
Molecular Mechanisms ◽  
Light Exposure ◽  
Photoreceptor Cells ◽  
Protective Role ◽  
Superoxide Production ◽  
Epithelial Tissue ◽  
Complex Activity ◽  
Tissue Organization ◽  
Nadph Oxidase Complex

Drosophila melanogaster Crumbs (Crb) and its mammalian orthologues (CRB1–3) share evolutionarily conserved but poorly defined roles in regulating epithelial polarity and, in photoreceptor cells, morphogenesis and stability. Elucidating the molecular mechanisms of Crb function is vital, as mutations in the human CRB1 gene cause retinal dystrophies. Here, we report that Crb restricts Rac1–NADPH oxidase-dependent superoxide production in epithelia and photoreceptor cells. Reduction of superoxide levels rescued epithelial defects in crb mutant embryos, demonstrating that limitation of superoxide production is a crucial function of Crb and that NADPH oxidase and superoxide contribute to the molecular network regulating epithelial tissue organization. We further show that reduction of Rac1 or NADPH oxidase activity or quenching of reactive oxygen species prevented degeneration of Crb-deficient retinas. Thus, Crb fulfills a protective role during light exposure by limiting oxidative damage resulting from Rac1–NADPH oxidase complex activity. Collectively, our results elucidate an important mechanism by which Crb functions in epithelial organization and the prevention of retinal degeneration.

scholarly journals Endothelium-specific activation of NAD(P)H oxidase in aortas of exogenously hyperinsulinemic rats

1999 ◽  
Vol 277 (6) ◽  
pp. E976-E983 ◽  
Author(s):  
Atsunori Kashiwagi ◽  
Kazuya Shinozaki ◽  
Yoshihiko Nishio ◽  
Hiroshi Maegawa ◽  
Yasuhiro Maeno ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Nadph Oxidase ◽  
Superoxide Anion ◽  
Chemiluminescence Method ◽  
Insulin Effect ◽  
Vascular Tissues ◽  
Text Production ◽  
Lucigenin Chemiluminescence

To examine the effects of chronic hyperinsulinemia on vascular tissues, we examined the production of superoxide anion ([Formula: see text]) in the aortic tissues of control and exogenously hyperinsulinemic rats performed by the implantation of an insulin pellet for 4 wk. [Formula: see text]production by aortic segments from hyperinsulinemic rats was 2.4-fold (lucigenin chemiluminescence method) and 1.7-fold (cytochrome c method) of that of control rats without any differences in [Formula: see text]degrading activities in aortic tissues, respectively ( P < 0.025). The increment was completely abolished in the presence of either 100 μmol/l apocynin (an inhibitor of NADPH oxidase) or 10 μmol/l diphenyleneiodonium (an inhibitor of flavin-containing enzyme) and was exclusively endothelium dependent. Consistently, NAD(P)H oxidase activities in endothelial homogenate in hyperinsulinemic rats were dose dependently stimulated above the values of control rats, although these activities in nonendothelial homogenate were not significantly stimulated by insulin. Furthermore, an insulin effect was also demonstrated 1 h after exposing aortic tissues to insulin. These results indicate that[Formula: see text] production specifically increases in endothelium of aortic tissues in chronic hyperinsulinemic rats through the activation of NAD(P)H oxidase.

scholarly journals Leishmania pifanoi Amastigotes Avoid Macrophage Production of Superoxide by Inducing Heme Degradation

2005 ◽  
Vol 73 (12) ◽  
pp. 8322-8333 ◽  
Author(s):  
Nam-Kha Pham ◽  
Jennifer Mouriz ◽  
Peter E. Kima
Keyword(s):  
Nadph Oxidase ◽  
Subcellular Fractions ◽  
Superoxide Production ◽  
Heme Oxygenase 1 ◽  
Heme Degradation ◽  
Nadph Oxidase Complex ◽  
Immature Form ◽  
Oxidase Enzyme ◽  
Infected Cells ◽  
Rate Limiting

ABSTRACT Whereas infections of macrophages by promastigote forms of Leishmania mexicana pifanoi induce the production of superoxide, infections by amastigotes barely induce superoxide production. Several approaches were employed to gain insight into the mechanism by which amastigotes avoid eliciting superoxide production. First, in experiments with nitroblue tetrazolium, we found that 25% of parasitophorous vacuoles (PVs) that harbor promastigotes are positive for the NADPH oxidase complex, in contrast to only 2% of PVs that harbor amastigotes. Second, confocal microscope analyses of infected cells labeled with antibodies to gp91phox revealed that this enzyme subunit is found in PVs that harbor amastigotes. Third, in immunoblots of subcellular fractions enriched with PVs from amastigote-infected cells and probed with antibodies to gp91phox, only the 65-kDa premature form of gp91phox was found. In contrast, subcellular fractions from macrophages that ingested zymosan particles contained both the 91- and 65-kDa forms of gp91phox. This suggested that only the immature form of gp91phox is recruited to PVs that harbor amastigotes. Given that gp91phox maturation is dependent on the availability of heme, we found that infections by Leishmania parasites induce an increase in heme oxygenase 1 (HO-1), the rate-limiting enzyme in heme degradation. Infections by amastigotes performed in the presence of metalloporphyrins, which are inhibitors of HO-1, resulted in superoxide production by infected macrophages. Taken together, we propose that Leishmania amastigotes avoid superoxide production by inducing an increase in heme degradation, which results in blockage of the maturation of gp91phox, which prevents assembly of the NADPH oxidase enzyme complex.

scholarly journals Superoxide Production in Galleria mellonella Hemocytes: Identification of Proteins Homologous to the NADPH Oxidase Complex of Human Neutrophils

2005 ◽  
Vol 73 (7) ◽  
pp. 4161-4170 ◽  
Author(s):  
David Bergin ◽  
Emer P. Reeves ◽  
Julie Renwick ◽  
Frans B. Wientjes ◽  
Kevin Kavanagh
Keyword(s):  
Immune Response ◽  
Nadph Oxidase ◽  
Galleria Mellonella ◽  
Cell Types ◽  
Oxidase Inhibitor ◽  
Superoxide Production ◽  
Human Neutrophils ◽  
Greater Wax Moth ◽  
Nadph Oxidase Complex ◽  
Insect Hemocytes

ABSTRACT The insect immune response has a number of structural and functional similarities to the innate immune response of mammals. The objective of the work presented here was to establish the mechanism by which insect hemocytes produce superoxide and to ascertain whether the proteins involved in superoxide production are similar to those involved in the NADPH oxidase-induced superoxide production in human neutrophils. Hemocytes of the greater wax moth (Galleria mellonella) were shown to be capable of phagocytosing bacterial and fungal cells. The kinetics of phagocytosis and microbial killing were similar in the insect hemocytes and human neutrophils. Superoxide production and microbial killing by both cell types were inhibited in the presence of the NADPH oxidase inhibitor diphenyleneiodonium chloride. Immunoblotting of G. mellonella hemocytes with antibodies raised against human neutrophil phox proteins revealed the presence of proteins homologous to gp91phox, p67phox, p47phox, and the GTP-binding protein rac 2. A protein equivalent to p40phox was not detected in insect hemocytes. Immunofluorescence analysis localized insect 47-kDa and 67-kDa proteins throughout the cytosol and in the perinuclear region. Hemocyte 67-kDa and 47-kDa proteins were immunoprecipitated and analyzed by matrix-assisted laser desorption ionization—time of flight analysis. The results revealed that the hemocyte 67-kDa and 47-kDa proteins contained peptides matching those of p67phox and p47phox of human neutrophils. The results presented here indicate that insect hemocytes phagocytose and kill bacterial and fungal cells by a mechanism similar to the mechanism used by human neutrophils via the production of superoxide. We identified proteins homologous to a number of proteins essential for superoxide production in human neutrophils and demonstrated that significant regions of the 67-kDa and 47-kDa insect proteins are identical to regions of the p67phox and p47phox proteins of neutrophils.

Superoxide generation and tyrosine kinase

2000 ◽  
Vol 78 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Su Yang ◽  
Martha Hardaway ◽  
George Sun ◽  
William L Ries ◽  
L Lyndon Key Jr
Keyword(s):  
Cell Surface ◽  
Nadph Oxidase ◽  
Tyrosine Kinase ◽  
B Lymphocytes ◽  
Specific Inhibitor ◽  
Superoxide Production ◽  
Regulatory Subunit ◽  
Superoxide Generation ◽  
Herbimycin A ◽  
Nadph Oxidase Complex

NADPH oxidase is a multi-subunit enzyme complex responsible for superoxide generation in many cells, for example, B-lymphocytes and osteoclasts. NADPH oxidase is localized on the cell surface and generates superoxide extracellularly. After synthesis, components of this oxidase are transported to the cell membrane where the functional NADPH oxidase complex is assembled. The mechanism by which the membrane-bound components are transported to the cell surface of osteoclasts remains unclear. In this study, we examined the role of tyrosine kinase activity in the transport of NADPH oxidase components. When B-lymphocytes and osteoclasts were treated with herbimycin A, a specific inhibitor of tyrosine kinase, superoxide production was significantly decreased. The amount of p91, the catalytic subunit of NADPH oxidase, was decreased in the cellular membrane of herbimycin A treated cells compared to untreated controls. Similar results were obtained for the movement of a regulatory subunit of the NADPH oxidase complex, p47, in B-lymphocytes. Thus, inhibition of tyrosine kinase decreases superoxide production by disrupting the translocation of the NADPH oxidase complex.

Cadmium decreased superoxide anion derived from NADPH oxidase through overload of calcium in wheat seedling

2020 ◽  
Vol 52 (5) ◽  
Author(s):  
Hongjuan Jiang ◽  
Yi Fu ◽  
Cuixiang Li ◽  
Mengying Chen ◽  
Zewei Gu ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Superoxide Anion ◽  
Wheat Seedling
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