In Vitro Effects of Certain Membrane-acting Agents on Superoxide and Hydrogen Peroxide Production, Protein Synthesis and Membrane ATPase Activity in Buffalo PMN Cells

Polymorphonuclear (PMN) cells play a key role in innate immunity, due to their ability to produce reactive oxidants such as superoxide (O2–) and hydrogen peroxide (H2O2), and to release antimicrobial proteins and peptides stored in their lysosomal granules. In the present study, the effects of the activation of buffalo PMN cells with various membrane-acting agents were evaluated in terms of O2– and H2O2 production, the activities of membrane ATPases, and protein synthesis. Studies involving the incorporation of 35S-methionine revealed significant protein-synthesising ability in resting PMN cells and in cells treated with lipopolysaccharide (LPS), as well as with opsonised zymosan (OZ). Protein synthesis, as judged by fluorography of the cytosolic fraction, showed more than 12 bands, whilst the cytoskeletal fraction showed 2–3 bands. PMN activation with concanavalin A (ConA), digitonin and sodium nitroprusside (SNP) resulted in increased O2– and H2O2 production. However, in the presence of anti-inflammatory agents such as indomethacin and cortisol, the production of O2– and H2O2 by these cells was found to decline. Studies pertaining to membrane ATPases revealed that verapamil hydrochloride (VpHCl) significantly increased total ATPase and Na+K+ATPase activity. ConA treatment yielded only a moderate level of activity. Similarly, digitonin up to 24μM also caused a significant increase in ATPase activity. Our observations indicate that these membrane-acting agents influenced oxygen-dependent and oxygen-independent microbicidal mechanisms in buffalo PMN cells.

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In vitro effects of hydrogen peroxide on ALF expression in male mouse germ cells

Reproduction Abstracts ◽

10.1530/repabs.1.p260 ◽

2014 ◽

Author(s):

Khaled S A Habas ◽

Diana Anderson ◽

Martin H Brinkworth

Keyword(s):

Hydrogen Peroxide ◽

Germ Cells ◽

Male Mouse ◽

In Vitro Effects

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Protein Synthesis in Human Leukocytes and Lymphocytes: 1. Effect of Steroids and Sterols

Blood ◽

10.1182/blood.v34.3.348.348 ◽

1969 ◽

Vol 34 (3) ◽

pp. 348-356 ◽

Cited By ~ 18

Author(s):

SEYMOUR WERTHAMER ◽

CARL HICKS ◽

LEONARD AMARAL

Keyword(s):

Protein Synthesis ◽

Steroid Hormones ◽

Plasma Protein ◽

Human Lymphocytes ◽

Amino Acid Incorporation ◽

Binding Factor ◽

In Vitro Effects ◽

Physiologic Role

Abstract The in vitro effects of sterols, cholesterol and 3-methyl cholanthrene and steroids, cortisol, prednisolone and testosterone on protein synthesis in separate popultions of human lymphocytes and leukocytes has been investigated. It has been shown that all agents used result in the inhibition of protein synthesis under these conditions. It has also been shown that the inhibitory mechanism of the steroid hormones requires the presence of plasma, presumably as a protein binding factor in order to achieve its effect. The sterol, cholesterol and 3-methyl cholanthrene, in the absence of plasma, still inhibit amino acid incorporation. However, in the case of cholesterol, the magnitude of inhibition is lower than that observed in the presence of plasma, perhaps indicating a partial plasma dependence. The results presented therefore support the hypothesis that the inhibition of lymphocyte protein synthesis by steroid hormones occurs only when the steroid is bound to a plasma protein. The physiologic role of the plasma protein-cortisol complex and its relation to the condition of lymphopenia in man is discussed.

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Genetic or pharmacological superoxide-hydrogen peroxide imbalances modulate the in vitro effects of lithium on glycogen synthase kinase-3β

Gene ◽

10.1016/j.gene.2018.02.046 ◽

2018 ◽

Vol 655 ◽

pp. 48-55 ◽

Cited By ~ 2

Author(s):

Fernanda Barbisan ◽

Verônica Farina Azzolin ◽

Gustavo Cardenas Monteiro ◽

Cibele F. Teixeira ◽

Moisés Henrique Mastella ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Glycogen Synthase ◽

Glycogen Synthase Kinase ◽

Glycogen Synthase Kinase 3Β ◽

In Vitro Effects

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Short-term effect of aldosterone on NEM-sensitive ATPase in rat collecting tubule

AJP Renal Physiology ◽

10.1152/ajprenal.1989.257.2.f177 ◽

1989 ◽

Vol 257 (2) ◽

pp. F177-F181 ◽

Cited By ~ 4

Author(s):

C. Khadouri ◽

S. Marsy ◽

C. Barlet-Bas ◽

A. Doucet

Keyword(s):

Atpase Activity ◽

Affinity Constant ◽

Short Term ◽

Collecting Tubule ◽

Lag Period ◽

In Vitro Effects ◽

Collecting Tubules

Because previous studies indicated that in the collecting tubule, N-ethylmaleimide (NEM)-sensitive ATPase, the biochemical equivalent of the proton pump, is controlled by mineralocorticoids in the long term, the present study was designed to investigate whether such control also exists in the short term. Therefore we investigated the in vivo and in vitro effects of aldosterone on the enzyme activity in cortical and outer medullary collecting tubules (CCT and MCT, respectively) from adrenalectomized rats. Administration of aldosterone (10 micrograms/kg body wt) markedly stimulated NEM-sensitive ATPase activity in the CCT and MCT within 3 h. Similarly, incubating CCT or MCT for 3 h in the presence of 10(-8) M aldosterone enhanced NEM-sensitive ATPase activity up to values similar to those previously measured in the corresponding nephron segments of normal rats. In vitro stimulation of NEM-sensitive ATPase was dose dependent in regard to aldosterone (apparent affinity constant approximately 10(-9) M), appeared after a 30-min lag period, and reached its maximum after 2-2.5 h. Finally, actinomycin D and cycloheximide totally abolished the in vitro action of aldosterone, demonstrating the involvement of protein synthesis in this process.

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