Lung redox homeostasis: emerging concepts

2000 ◽  
Vol 279 (3) ◽  
pp. L413-L417 ◽  
Author(s):  
Marilyn P. Merker ◽  
Bruce R. Pitt ◽  
Augustine M. Choi ◽  
Paul M. Hassoun ◽  
Christopher A. Dawson ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Electron Transport ◽  
Nadph Oxidase ◽  
Redox Homeostasis ◽  
Cell Types ◽  
Xanthine Dehydrogenase ◽  
Zinc Binding ◽  
Cell Type ◽  
Predominant Cell Type ◽  
Lung Endothelium

This symposium was organized to present some aspects of current research pertaining to lung redox function. Focuses of the symposium were on roles of pulmonary endothelial NADPH oxidase, xanthine oxidase (XO)/xanthine dehydrogenase (XDH), heme oxygenase (HO), transplasma membrane electron transport (TPMET), and the zinc binding protein metallothionein (MT) in the propagation and/or protection of the lung or other organs from oxidative injury. The presentations were chosen to reflect the roles of both intracellular (metallothionein, XO/XDH, and HO) and plasma membrane (NADPH oxidase, XO/XDH, and unidentified TPMET) redox proteins in these processes. Although the lung endothelium was the predominant cell type under consideration, at least some of the proposed mechanisms operate in or affect other cell types and organs as well.

scholarly journals Plasma membrane electron transport in pancreatic β-cells is mediated in part by NQO1

2011 ◽  
Vol 301 (1) ◽  
pp. E113-E121 ◽  
Author(s):  
Joshua P. Gray ◽  
Timothy Eisen ◽  
Gary W. Cline ◽  
Peter J. S. Smith ◽  
Emma Heart
Keyword(s):  
Plasma Membrane ◽  
Electron Transport ◽  
Potassium Cyanide ◽  
Cell Types ◽  
Glycolytic Flux ◽  
Dependent Manner ◽  
Β Cells ◽  
Quinone Oxidoreductase ◽  
Plasma Membrane Electron Transport ◽  
Diphenylene Iodonium

Plasma membrane electron transport (PMET), a cytosolic/plasma membrane analog of mitochondrial electron transport, is a ubiquitous system of cytosolic and plasma membrane oxidoreductases that oxidizes cytosolic NADH and NADPH and passes electrons to extracellular targets. While PMET has been shown to play an important role in a variety of cell types, no studies exist to evaluate its function in insulin-secreting cells. Here we demonstrate the presence of robust PMET activity in primary islets and clonal β-cells, as assessed by the reduction of the plasma membrane-impermeable dyes WST-1 and ferricyanide. Because the degree of metabolic function of β-cells (reflected by the level of insulin output) increases in a glucose-dependent manner between 4 and 10 mM glucose, PMET was evaluated under these conditions. PMET activity was present at 4 mM glucose and was further stimulated at 10 mM glucose. PMET activity at 10 mM glucose was inhibited by the application of the flavoprotein inhibitor diphenylene iodonium and various antioxidants. Overexpression of cytosolic NAD(P)H-quinone oxidoreductase (NQO1) increased PMET activity in the presence of 10 mM glucose while inhibition of NQO1 by its inhibitor dicoumarol abolished this activity. Mitochondrial inhibitors rotenone, antimycin A, and potassium cyanide elevated PMET activity. Regardless of glucose levels, PMET activity was greatly enhanced by the application of aminooxyacetate, an inhibitor of the malate-aspartate shuttle. We propose a model for the role of PMET as a regulator of glycolytic flux and an important component of the metabolic machinery in β-cells.

Nuclear membrane receptors for ET-1 in cardiovascular function

2011 ◽  
Vol 300 (2) ◽  
pp. R251-R263 ◽  
Author(s):  
Ghassan Bkaily ◽  
Levon Avedanian ◽  
Johny Al-Khoury ◽  
Chantale Provost ◽  
Moni Nader ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Nuclear Membrane ◽  
Nuclear Translocation ◽  
Vascular Endothelial Cells ◽  
Cell Types ◽  
Membrane Receptors ◽  
Vascular Endothelial ◽  
Cell Type ◽  
Nuclear Membranes ◽  
New Generation

Plasma membrane endothelin type A (ETA) receptors are internalized and recycled to the plasma membrane, whereas endothelin type B (ETB) receptors undergo degradation and subsequent nuclear translocation. Recent studies show that G protein-coupled receptors (GPCRs) and ion transporters are also present and functional at the nuclear membranes of many cell types. Similarly to other GPCRs, ETA and ETB are present at both the plasma and nuclear membranes of several cardiovascular cell types, including human cardiac, vascular smooth muscle, endocardial endothelial, and vascular endothelial cells. The distribution and density of ETARs in the cytosol (including the cell membrane) and the nucleus (including the nuclear membranes) differ between these cell types. However, the localization and density of ET-1 and ETB receptors are similar in these cell types. The extracellular ET-1-induced increase in cytosolic ([Ca]c) and nuclear ([Ca]n) free Ca2+ is associated with an increase of cytosolic and nuclear reactive oxygen species. The extracellular ET-1-induced increase of [Ca]c and [Ca]n as well as intracellular ET-1-induced increase of [Ca]n are cell-type dependent. The type of ET-1 receptor mediating the extracellular ET-1-induced increase of [Ca]c and [Ca]n depends on the cell type. However, the cytosolic ET-1-induced increase of [Ca]n does not depend on cell type. In conclusion, nuclear membranes' ET-1 receptors may play an important role in overall ET-1 action. These nuclear membrane ET-1 receptors could be targets for a new generation of antagonists.

scholarly journals MIGRATION OF GLYCOPROTEIN FROM THE GOLGI APPARATUS TO THE SURFACE OF VARIOUS CELL TYPES AS SHOWN BY RADIOAUTOGRAPHY AFTER LABELED FUCOSE INJECTION INTO RATS

1974 ◽  
Vol 60 (1) ◽  
pp. 258-284 ◽  
Author(s):  
Gary Bennett ◽  
C. P. Leblond ◽  
Antonio Haddad
Keyword(s):  
Plasma Membrane ◽  
Electron Microscope ◽  
Golgi Apparatus ◽  
Early Time ◽  
Cell Types ◽  
Cell Type ◽  
Time Intervals ◽  
Cell Coat ◽  
Golgi Region ◽  
Silver Grains

A single intravenous injection of L-[3H]fucose, a specific glycoprotein precursor, was given to young 35–45 g rats which were sacrificed at times varying between 2 min and 30 h later. Radioautography of over 50 cell types, including renewing and nonrenewing cells, was carried out for light and electron microscope study. At early time intervals (2–10 min after injection), light microscope radioautography showed a reaction over nearly all cells investigated in the form of a discrete clump of silver grains over the Golgi region. This reaction varied in intensity and duration from cell type to cell type. Electron microscope radioautographs of duodenal villus columnar cells and kidney proximal and distal tubule cells at early time intervals revealed that the silver grains were restricted to Golgi saccules. These observations are interpreted to mean that glycoproteins undergoing synthesis incorporate fucose in the saccules of the Golgi apparatus. Since fucose occurs as a terminal residue in the carbohydrate side chains of glycoproteins, the Golgi saccules would be the site of completion of synthesis of these side chains. At later time intervals, light and electron microscope radioautography demonstrated a decrease in the reaction intensity of the Golgi region, while reactions appeared over other parts of the cells: lysosomes, secretory material, and plasma membrane. The intensity of the reactions observed over the plasma membrane varied considerably in various cell types; furthermore the reactions were restricted to the apical surface in some types, but extended to the whole surface in others. Since the plasma membrane is covered by a "cell coat" composed of the carbohydrate-rich portions of membrane glycoproteins, it is concluded that newly formed glycoproteins, after acquiring fucose in the Golgi apparatus, migrate to the cell surface to contribute to the cell coat. This contribution implies turnover of cell coat glycoproteins, at least in nonrenewing cell types, such as those of kidney tubules. In the young cells of renewing populations, e.g. those of gastro-intestinal epithelia, the new glycoproteins seem to contribute to the growth as well as the turnover of the cell coat. The differences in reactivity among different cell types and cell surfaces imply considerable differences in the turnover rates of the cell coats.

Distribution of leucocyte populations, and milk composition, in milk fractions of healthy quarters in dairy cows

2005 ◽  
Vol 72 (4) ◽  
pp. 486-492 ◽  
Author(s):  
Hande Sarikaya ◽  
Claudia Werner-Misof ◽  
Melanie Atzkern ◽  
Rupert M Bruckmaier
Keyword(s):  
Dairy Cows ◽  
Cell Types ◽  
Milk Composition ◽  
Polymorphonuclear Neutrophils ◽  
Cell Type ◽  
Maximum Value ◽  
Predominant Cell Type ◽  
Teat Canal ◽  
Main Entrance

The goal of the study was to evaluate the composition of leucocyte populations in different milk fractions as a basis on which to judge their possible role in the immune response in different compartments of the udder. The milk of one healthy quarter of nine dairy cows (SCC/quarter [les ]125000/ml; bacteriologically negative) was removed separately and during the course of milking divided into: cisternal milk (C), alveolar milk 0–25%, 25–50%, 50–75%, 75–100% (A25; A50; A75; A100, respectively) and residual milk (R). Each fraction was analysed for the main constituents, SCC and distribution of leucocyte populations and their viability. The content of fat increased steadily during milking and reached highest values in R. Protein and lactose increased from C to A25, decreased from A25 to A100 and reached their minimum in R. Na and Cl ion levels diminished from C to A25 and thereafter increased from A50 to R. Electrical Conductivity (EC) also decreased from C to A25 but remained similar within the alveolar samples and reached a minimum in R. SCC decreased from C to a minimum in A25 and increased subsequently to a significant maximum in R. Somatic cell viability increased throughout consecutive fractions with a maximum value in R. The ratio of cell populations in the various milk fractions showed a reverse trend of macrophages (M) and polymorphonuclear neutrophils (PMN). M values were highest in C while PMN levels increased to their maximum in the R fraction. The lymphocyte (L) fraction remained similar in C, A25, A50, A75 and R but was higher in A100. Proportions of L, PMN and M were, respectively, 9·3%, 38·2%, 52·3% in C, 10·9%, 64%, 25·1% in A25–A100 and 10·2%, 64·9%, 24·8% in R. Numbers of L, PMN and M in milk showed a similar pattern for all three cell types: high levels in C decreased to a minimum at A25 and increased steadily thereafter to their maxima in R. It is concluded that, for healthy quarters, M, the predominant cell type in C, are located near the teat canal, the main entrance of pathogens. Obviously they are the first immunological barriers for invading pathogens. In contrast, PMN are the most important population in the alveolar compartment. However, each leucocyte fraction had a higher concentration in C than in early alveolar fractions, thus indicating the crucial role of immune defence in the cisternal compartment.

scholarly journals Mechanistic insight into heterogeneity of trans-plasma membrane electron transport in cancer cell types

2019 ◽  
Vol 1860 (8) ◽  
pp. 628-639 ◽  
Author(s):  
Harry G. Sherman ◽  
Carolyn Jovanovic ◽  
Alaa Abuawad ◽  
Dong-Hyun Kim ◽  
Hilary Collins ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Electron Transport ◽  
Cancer Cell ◽  
Cell Types ◽  
Mechanistic Insight ◽  
Plasma Membrane Electron Transport ◽  
Insight Into

scholarly journals Cortical Cell Types and their Distribution in Wool Fibres

1984 ◽  
Vol 37 (4) ◽  
pp. 237 ◽  
Author(s):  
Donald FG Orwin ◽  
Joy L Woods ◽  
Stephen L Ranford
Keyword(s):  
Cross Section ◽  
Cortical Cell ◽  
Cell Types ◽  
Blue Staining ◽  
Cell Type ◽  
Predominant Cell Type ◽  
Percentage Area ◽  
Log Linear ◽  
The Relationship ◽  
Linear Manner

A method of determining cell types in wool fibres by methylene-blue staining has been extended to allow relationships between cortical cell type and cortical diameter to be studied in wools from individual sheep. Application of the method to wools from 12 sheep from six breeds showed that orthocortical cells were the predominant cell type produced. The percentage area occupied by orthocortical cells in a fibre cross-section increased with increasing cortical diameter in either a curvilinear (log-linear) or a linear manner. Nutritional stress or season may have affected the relationship in some sheep.

Functional morphology of the coelomocytes of the larval oysters (Crassostrea virginica and Crassostrea gigas)

1980 ◽  
Vol 60 (4) ◽  
pp. 947-957 ◽  
Author(s):  
Ralph Elston
Keyword(s):  
Crassostrea Virginica ◽  
Functional Morphology ◽  
Crassostrea Gigas ◽  
Cell Types ◽  
The Other ◽  
Cell Type ◽  
Ultrastructural Examination ◽  
Predominant Cell Type ◽  
Differential Cell ◽  
Adult Oyster

The functional morphology of the coelomocytes of larval oysters, Crassostrea virginica and C. gigas, based on observations of live animals and histological and ultrastructural examination of tissues, is presented. Two predominant types of coelomocytes were found in the larval oysters. One, the SER cell, not found in the adult oyster, is large with a spheroidal nucleus, and exhibits basophilic cytoplasm which consists of abundant smooth endoplastic reticulum. This cell appears to participate in metabolic conversion processes. The other predominant cell type, the phagocyte, appears identical to the phagocyte observed in the adult oyster. Both differential cell types were observed from one day post fertilization to metamorphosis, the oldest stage studied.

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