The effect of porphyrins on cellular redox systems: a study on the dark effect of porphyrins on phagocytes

1993 ◽  
Vol 23 (11) ◽  
pp. 716-723 ◽  
Author(s):  
J. C. KONINGSBERGER ◽  
B. S. VAN ASBECK ◽  
J. VAN HATTUM ◽  
L. J. J. M. WIEGMAN ◽  
G. P. VAN BERGE HENEGOUWEN ◽  
...  
Keyword(s):  
Redox Systems ◽  
Cellular Redox ◽  
Dark Effect

scholarly journals Cell type-specific differences in redox regulation and proliferation after low UVA doses

2018 ◽  
Author(s):  
Sylwia Ciesielska ◽  
Patryk Bil ◽  
Karolina Gajda ◽  
Aleksandra Poterala-Hejmo ◽  
Dorota Hudy ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Redox Regulation ◽  
Cellular Proliferation ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Cell Type ◽  
Redox Systems ◽  
Human Colon Cancer ◽  
Cellular Redox ◽  
Hct116 Cells

AbstractUltraviolet A (UVA) radiation is harmful for living organisms but in low doses may stimulate cell proliferation. Our aim was to examine the relationships between exposure to different low UVA doses, cellular proliferation, and changes in cellular reactive oxygen species levels. In human colon cancer (HCT116) and melanoma (Me45) cells exposed to UVA doses comparable to environmental, the highest doses (30-50 kJ/m2) reduced clonogenic potential but some lower doses (1 and 10 kJ/m2) induced proliferation. This effect was cell type and dose specific. In both cell lines the levels of reactive oxygen species and nitric oxide fluctuated with dynamics which were influenced differently by UVA; in Me45 cells decreased proliferation accompanied the changes in the dynamics of H2O2 while in HCT116 cells those of superoxide. Genes coding for proteins engaged in redox systems were expressed differently in each cell line; transcripts for thioredoxin, peroxiredoxin and glutathione peroxidase showed higher expression in HCT116 cells whereas those for glutathione transferases and copper chaperone were more abundant in Me45 cells. We conclude that these two cell types utilize different pathways for regulating their redox status. Many mechanisms engaged in maintaining cellular redox balance have been described. Here we show that the different cellular responses to a stimulus such as a specific dose of UVA may be consequences of the use of different redox control pathways. Assays of superoxide and hydrogen peroxide level changes after exposure to UVA may clarify mechanisms of cellular redox regulation and help in understanding responses to stressing factors.

Two different cellular redox systems regulate the DNA-binding activity of the p50 subunit of NF-κB in vitro

Gene ◽  
1994 ◽  
Vol 145 (2) ◽  
pp. 197-203 ◽  
Author(s):  
Mitomo Katsuyuki ◽  
Nakayama Kohzo ◽  
Fujimoto Kotaro ◽  
Sun Xiangao ◽  
Seki Shuji ◽  
...  
Keyword(s):  
Dna Binding ◽  
Binding Activity ◽  
Redox Systems ◽  
Cellular Redox ◽  
Dna Binding Activity

scholarly journals Understanding Cellular Redox Homeostasis: A Challenge for Precision Medicine

2021 ◽  
Vol 23 (1) ◽  
pp. 106
Author(s):  
Verena Tretter ◽  
Beatrix Hochreiter ◽  
Marie Louise Zach ◽  
Katharina Krenn ◽  
Klaus Ulrich Klein
Keyword(s):  
Oxidative Stress ◽  
Precision Medicine ◽  
Redox Homeostasis ◽  
Reactive Species ◽  
Scientific Field ◽  
Redox Systems ◽  
Cellular Redox ◽  
Redox Biology ◽  
Living Organisms ◽  
Large Repertoire

Living organisms use a large repertoire of anabolic and catabolic reactions to maintain their physiological body functions, many of which include oxidation and reduction of substrates. The scientific field of redox biology tries to understand how redox homeostasis is regulated and maintained and which mechanisms are derailed in diverse pathological developments of diseases, where oxidative or reductive stress is an issue. The term “oxidative stress” is defined as an imbalance between the generation of oxidants and the local antioxidative defense. Key mediators of oxidative stress are reactive species derived from oxygen, nitrogen, and sulfur that are signal factors at physiological concentrations but can damage cellular macromolecules when they accumulate. However, therapeutical targeting of oxidative stress in disease has proven more difficult than previously expected. Major reasons for this are the very delicate cellular redox systems that differ in the subcellular compartments with regard to their concentrations and depending on the physiological or pathological status of cells and organelles (i.e., circadian rhythm, cell cycle, metabolic need, disease stadium). As reactive species are used as signaling molecules, non-targeted broad-spectrum antioxidants in many cases will fail their therapeutic aim. Precision medicine is called to remedy the situation.

scholarly journals Cellular Redox Systems Impact the Aggregation of Cu,Zn Superoxide Dismutase Linked to Familial Amyotrophic Lateral Sclerosis

2016 ◽  
Vol 291 (33) ◽  
pp. 17197-17208 ◽  
Author(s):  
Cristina Álvarez-Zaldiernas ◽  
Jun Lu ◽  
Yujuan Zheng ◽  
Hongqian Yang ◽  
Juan Blasi ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Protein Misfolding ◽  
Wild Type ◽  
Redox Systems ◽  
Cellular Redox ◽  
Oxidation Reduction ◽  
Cellular Oxidation ◽  
Inherited Mutations ◽  
Human Sod1 ◽  
Lateral Sclerosis

Protein misfolding is implicated in neurodegenerative diseases such as ALS, where mutations of superoxide dismutase 1 (SOD1) account for about 20% of the inherited mutations. Human SOD1 (hSOD1) contains four cysteines, including Cys57 and Cys146, which have been linked to protein stability and folding via forming a disulfide bond, and Cys6 and Cys111 as free thiols. But the roles of the cellular oxidation-reduction (redox) environment in SOD1 folding and aggregation are not well understood. Here we explore the effects of cellular redox systems on the aggregation of hSOD1 proteins. We found that the known hSOD1 mutations G93A and A4V increased the capability of the thioredoxin and glutaredoxin systems to reduce hSOD1 compared with wild-type hSOD1. Treatment with inhibitors of these redox systems resulted in an increase of hSOD1 aggregates in the cytoplasm of cells transfected with mutants but not in cells transfected with wild-type hSOD1 or those containing a secondary C111G mutation. This aggregation may be coupled to changes in the redox state of the G93A and A4V mutants upon mild oxidative stress. These results strongly suggest that the thioredoxin and glutaredoxin systems are the key regulators for hSOD1 aggregation and may play critical roles in the pathogenesis of ALS.

scholarly journals Stimulation of cystine uptake by nitric oxide: regulation of endothelial cell glutathione levels

1999 ◽  
Vol 276 (4) ◽  
pp. C803-C811 ◽  
Author(s):  
Hongfei Li ◽  
Zermeena M. Marshall ◽  
A. Richard Whorton
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Chronic Exposure ◽  
Time Course ◽  
Raw 264.7 Cells ◽  
Continuous Exposure ◽  
Redox Systems ◽  
Extracellular Glutamate ◽  
Amino Acid Transport System ◽  
Cellular Redox

Nitric oxide (NO) is known to produce some of its biological activity through modification of cellular thiols. Return of cellular thiols to their basal state requires the activity of the GSH redox cycle, suggesting important interactions between NO signaling and regulation of cellular redox status. Because continuous exposure to NO may lead to adaptive responses in cellular redox systems, we investigated the effects of NO on cellular GSH levels in vascular endothelial cells. Acute exposure (1 h) of cells to >1 mM S-nitroso- N-acetyl-penicillamine (SNAP) led to depletion of GSH. On the other hand, chronic exposure to lower concentrations of SNAP (≤1 mM) led to a progressive increase in cytosolic GSH, reaching fourfold above basal by 16 h. The mechanism may involve an increase in GSH biosynthesis through effects on biosynthetic enzymes or through increased supply of cysteine, the limiting substrate. In this regard, we report that chronic exposure to SNAP led to a concentration-dependent increase in cystine uptake over a time course similar to that seen for elevation of GSH. The effect of SNAP on cystine uptake was inhibitable by either cycloheximide or actinomycin D, suggesting a requirement for both RNA and protein synthesis. Furthermore, uptake was Na+independent and was blocked by extracellular glutamate. Extracellular glutamate also blocked SNAP-mediated elevation of cytosolic GSH. Finally, in a coculture model, NO produced by cytokine-pretreated RAW 264.7 cells increased both GSH levels and cystine uptake in naive endothelial cells. These findings strongly suggest that NO leads to adaptive induction of the[Formula: see text] amino acid transport system, increased cystine uptake, and elevation of intracellular GSH levels.

scholarly journals Redox Systems in Botrytis cinerea: Impact on Development and Virulence

2014 ◽  
Vol 27 (8) ◽  
pp. 858-874 ◽  
Author(s):  
Anne Viefhues ◽  
Jens Heller ◽  
Nora Temme ◽  
Paul Tudzynski
Keyword(s):  
Botrytis Cinerea ◽  
Redox Homeostasis ◽  
Thioredoxin Reductase ◽  
Redox System ◽  
Redox Status ◽  
Redox Systems ◽  
Gene Encoding ◽  
Cellular Redox ◽  
Thioredoxin System ◽  
The Impact

The thioredoxin system is of great importance for maintenance of cellular redox homeostasis. Here, we show that it has a severe influence on virulence of Botrytis cinerea, demonstrating that redox processes are important for host-pathogen interactions in this necrotrophic plant pathogen. The thioredoxin system is composed of two enzymes, the thioredoxin and the thioredoxin reductase. We identified two genes encoding for thioredoxins (bctrx1, bctrx2) and one gene encoding for a thioredoxin reductase (bctrr1) in the genome of B. cinerea. Knockout mutants of bctrx1 and bctrr1 were severely impaired in virulence and more sensitive to oxidative stress. Additionally, Δbctrr1 showed enhanced H2O2 production and retarded growth. To investigate the impact of the second major cellular redox system, glutathione, we generated deletion mutants for two glutathione reductase genes. The effects were only marginal; deletion of bcglr1 resulted in reduced germination and, correspondingly, to retarded infection as well as reduced growth on minimal medium, whereas bcglr2 deletion had no distinctive phenotype. In summary, we showed that the balanced redox status maintained by the thioredoxin system is essential for development and pathogenesis of B. cinerea, whereas the second major cellular redox system, the glutathione system, seems to have only minor impact on these processes.

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