Cytochrome b 558 and hydrogen peroxide production in small intensely fluorescent cells of sympathetic ganglia

Kummer, Wolfgang; Acker, H.

doi:10.1007/s004180050099

Cited by 9 publications

(6 citation statements)

References 34 publications

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“…They are reported to be abundant during human development but increasingly difficult to find with increasing postnatal age [13]. Recently evidence of a capacity for oxygen sensing by this cell type, similar to cells of glomus caroticum, was reported [14]. We show here that SIF-like differentiation in neuroblastoma is clearly blood vesseldependent and, most likely, involves oxygen sensing by tumor cells suffering from hypoxia, demonstrated by the coexpression of chromaffin markers and VEGF165.…”

Section: Discussionsupporting

confidence: 53%

Evidence of chromaffin oxygen sensing in neuroblastoma

Hedborg

Franklin

Norrman

et al. 2001

Med. Pediatr. Oncol.

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With the aid of IGF2 and VEGF in situ hybridization; tyrosine hydroxylase, chromogranin A, and Ki67 immunohistochemistry; and TUNEL staining applied to a large series of clinical neuroblastomas and to an animal model, we show here that stroma-poor neuroblastomas show evidence of chromaffin differentiation similar to that of type 1 small intensely fluorescent (SIF) cells and that this occurs in a vascular-dependent fashion, indicating a role for local tumor hypoxia in the differentiation process.

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Section: Discussionsupporting

confidence: 53%

Evidence of chromaffin oxygen sensing in neuroblastoma

Hedborg

Franklin

Norrman

et al. 2001

Med. Pediatr. Oncol.

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“…-dependent H # O # production has been reported in pulmonary neuroepithelial bodies [20], rat carotid body preparations [21], HepG2 cells [22], bovine pulmonary artery cells [23] and primary hepatocytes [5]. It appears that a haem-containing NADPH oxidase isoenzyme [24,25] of the cytochrome b type, similar to that in neutrophils [26], is involved in H # O # production. The hypothesis that an NADPH oxidase is part of the O # sensor is in line with results from this and earlier studies on the induction of the EPO, aldolase A and PCK genes.…”

Section: Discussionmentioning

confidence: 99%

Involvement of a local Fenton reaction in the reciprocal modulation by O2 of the glucagon-dependent activation of the phosphoenolpyruvate carboxykinase gene and the insulin-dependent activation of the glucokinase gene in rat hepatocytes

Kietzmann¹,

Porwol

Zierold

et al. 1998

Biochemical Journal

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H2O2 mimicked the action of periportal pO2 in the modulation by O2 of the glucagon-dependent activation of the phosphoenolpyruvate carboxykinase (PCK) gene and the insulin-dependent activation of the glucokinase (GK) gene. H2O2 can be converted in the presence of Fe2+ in a Fenton reaction into hydroxyl anions and hydroxyl radicals (.OH). The hydroxyl radicals are highly reactive and might interfere locally with transcription factors. It was the aim of the present study to investigate the role of and to localize such a Fenton reaction. Hepatocytes cultured for 24 h were treated under conditions mimicking periportal or perivenous pO2 with glucagon or insulin plus the iron chelator desferrioxamine (DSF) or the hydroxyl radical scavenger dimethylthiourea (DMTU) to inhibit the Fenton reaction. PCK mRNA was induced by glucagon maximally under conditions of periportal pO2 and half-maximally under venous pO2. GK mRNA was induced by insulin with reciprocal modulation by O2. DSF and DMTU reduced the induction of PCK mRNA to about half-maximal and increased the induction of GK mRNA to maximal under both O2 tensions. Hydroxyl radical formation was maximal under arterial pO2. Perivenous pO2, DSF and DMTU each decreased the formation of .OH to about 70% of control. The Fenton reaction could be localized in a perinuclear space by confocal laser microscopy and three-dimensional reconstruction techniques. In the same compartment, iron could be detected by electron-probe X-ray microanalysis. Thus a local Fenton reaction is involved in the O2 signalling, which modulated the glucagon- and insulin-dependent PCK gene and GK gene activation.

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“…Nonfluorescent DHR 123 is converted into fluorescent rhodamine 123 by ROS generated inside the cell (Görlach et al 1994;Kummer and Acker 1997). Nonfluorescent DHR 123 is converted into fluorescent rhodamine 123 by ROS generated inside the cell (Görlach et al 1994;Kummer and Acker 1997).…”

Section: Isolation Of Leukocytesmentioning

confidence: 99%

NADPH oxidase subunits and superoxide production in porcine pulmonary artery endothelial cells

Höhler

Holzapfel

Kummer

2000

Histochem Cell Biol

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An NADPH oxidase complex composed of a membrane-bound flavocytochrome b 558 consisting of two subunits (p22 phox and gp91 phox ) and cytosolic activating factors (p47 phox and p67 phox ) generates superoxide anions from oxygen in the respiratory burst of phagocytic cells. Inconsistent results have been previously obtained concerning its additional occurrence in pulmonary artery endothelial cells (PAEC), and this issue was addressed in the present study. PAEC isolated from porcine pulmonary trunk contained mRNA for p22 phox and gp91 phox as demonstrated by reverse transcription-polymerase chain reaction. Immunohistochemistry demonstrated cytochrome subunits, p22 phox , gp91 phox , p47 phox , and p67 phox , both in vitro in isolated PAEC and in situ in endothelial cells in tissue sections of the pulmonary trunk. Isolated PAEC generated reactive oxygen species (ROS; measured by lucigenin-induced chemiluminescence and conversion of dihydrorhodamine 123 into rhodamine 123) in response to stimulation with phorbol 12-myristate 13-acetate. This stimulated ROS production was sensitive to the flavoprotein inhibitor diphenyleneiodonium, and reduced when the superoxide scavenger superoxide dismutase was added. Chemiluminescence measurements of superoxide generation by stimulated PAEC accounted for approximately 1% of that generated by stimulated peritoneal macrophages. The data demonstrate a low-output NADPH oxidase system in porcine PAEC sharing several components with that identified in phagocytic cells.

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Cytochrome b 558 and hydrogen peroxide production in small intensely fluorescent cells of sympathetic ganglia

Cited by 9 publications

References 34 publications

Evidence of chromaffin oxygen sensing in neuroblastoma

Evidence of chromaffin oxygen sensing in neuroblastoma

Involvement of a local Fenton reaction in the reciprocal modulation by O2 of the glucagon-dependent activation of the phosphoenolpyruvate carboxykinase gene and the insulin-dependent activation of the glucokinase gene in rat hepatocytes

NADPH oxidase subunits and superoxide production in porcine pulmonary artery endothelial cells

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