Oxidative Modification of Redox Proteins: Role in the Regulation of HBL-100 Cell Proliferation

Introduction.High rates of cancer incidence and mortality worldwide dictate the necessity of developing new methodological approaches in understanding the molecular mechanisms of cancer progression associated with intracellular redox regulation imbalance.The objectiveof the study was to evaluate the role of protein carbonylation in regulating breast cancer cell proliferation under redox status modulation.Materials and Methods. In the intact breast cancer cells and in the cells cultured under redox status modulation using 5mM N-ethylmaleimide (an - SH group blocker) and 5 Mm 1,4-dithioerythritol (a thiol group protector), the concentration of thioredoxin and its carbonylated form was measured using Western blot analysis. The activity of thioredoxin reductase and the level of protein carbonyl derivatives were determined using spectrophotometry. Cell cycle phase distribution was evaluated by flow cytometry.Results and Discussion. Under the effect of N-ethylmaleimide, cell cycle arrest in the S-phase was confirmed by oxidative modification of proteins, including thioredoxin carbonylation. When culturing MCF-7 cells in the presence of 1,4-dithioerythritol, cell cycle arrest in the G0/G1 phases was associated with a rise in the concentrations of reduced thioredoxin and glutathione forms.Conclusion.The thioredoxin system and oxidative modification of proteins are involved in redox-dependent modulation of breast cancer cell proliferation. Studies in the area of redox proteomics offer great potential to seek molecular targets of malignant transformation of breast cells.

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Oxidative modification of low-density lipoproteins by mesangial cells.

Journal of the American Society of Nephrology ◽

10.1681/asn.v42187 ◽

1993 ◽

Vol 4 (2) ◽

pp. 187-194

Author(s):

W F Keane ◽

M P O'Donnell ◽

B L Kasiske ◽

Y Kim

Keyword(s):

Cell Proliferation ◽

Mesangial Cell ◽

Thymidine Incorporation ◽

Mesangial Cells ◽

Chemical Oxidation ◽

Oxidative Modification ◽

Low Density ◽

Cell Numbers ◽

Human Mesangial Cell ◽

Mesangial Cell Proliferation

Because hypercholesterolemia and mesangial cell proliferation may be important in the pathogenesis of glomerulosclerosis, the effects of low-density lipoprotein (LDL) on human mesangial cell proliferation were evaluated. Native LDL (20 to 200 micrograms/mL) caused a dose-dependent increase in (3H)thymidine incorporation and increased mesangial cell numbers over 96 h. The mitogenic effect of LDL was partially blocked by the inhibition of cytochrome P-450, but not by the inhibition of cyclooxygenase or lipoxygenase pathways. Higher LDL concentrations (1,000 to 2,000 micrograms/mL) inhibited (3H)thymidine incorporation and reduced cell numbers, possibly as a result of the oxidative modification of LDL, indicated by an increase in thiobarbituric reactive substances. This peroxidation of LDL involved superoxide, because superoxide dismutase and butylated hydroxytoluene prevented it, whereas hydroxyl radical scavengers were without effect. Native LDL subjected to chemical oxidation by copper sulfate also inhibited mesangial cell proliferation. These results suggest that low concentrations of LDL may stimulate human mesangial cell proliferation, which may, in turn, cause the production of reactive oxygen molecules. Moreover, the oxidative modification of LDL may mediate the toxic effects of high LDL concentrations on human mesangial cells.

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The Role of Redox Proteins in Arresting Proliferation of Breast Epithelial Cells Under Oxidative Stress

Annals of the Russian academy of medical sciences ◽

10.15690/vramn1030 ◽

2018 ◽

Vol 73 (5) ◽

pp. 289-293

Author(s):

Evgeniya V. Shakhristova ◽

Elena A. Stepovaya ◽

Evgeniy V. Rudikov ◽

Olga S. Sushitskaya ◽

Daria O. Rodionova ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Cycle ◽

Cell Proliferation ◽

Epithelial Cells ◽

Breast Epithelial Cells ◽

Redox Proteins ◽

Cell Cycle Inhibitor ◽

A Cell ◽

Breast Epithelial

Background: Redox status imbalance against the backdrop of oxidative stress development underlies the pathogenesis of a whole range of diseases. Many intracellular proteins contain free thiol groups and undergo redox regulation which is one of the key processes in controlling cell proliferation. Thioredoxin and glutaredoxin are involved in maintaining intracellular redox homeostasis and act as candidates in regulating proliferation. This provides prospects for future development of methods for diagnosis and targeted therapy of socially sensitive diseases accompanied by oxidative stress. The aim of the study is to reveal the role of redox proteins in molecular mechanisms of regulating HBL-100 breast epithelial cell proliferation under the effect of roscovitine, a cell cycle inhibitor. Materials and methods: Two research groups were formed. They included HBL-100 human breast epithelial cells incubated in the presence and absence of 20 mcM roscovitine for 18 hours. The intracellular thioredoxin levels were determined using Western blot analysis with specific monoclonal antibodies. Distribution of the cells among cell cycle phases were evaluated by flow cytometry. The activity of glutathione reductase, glutathione peroxidase, and thioredoxin reductase were measured by spectrophotometry. Results: Under the effect of roscovitine in the HBL-100 cells, cell cycle arrest in the G2/М phases occurred and oxidative stress developed. In the meantime, the decrease in the thioredoxin and glutaredoxin concentrations was registered along with the change in the functional activity of glutathione-dependent enzymes. Conclusions: Application of roscovitine, a cell cycle inhibitor, allowed creating a model of oxidative stress in the breast epithelial cells against the backdrop of inhibited cell proliferation. We identified that thioredoxin and glutaredoxin contributed to impairment of cell cycle progression. It points at a possibility to regulate cell proliferation by modulating the functional features of cellular redox-dependent proteins in different pathologies accompanied by oxidative stress.

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Fibroblasts During Hypertrophic Scar Formation and Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072587 ◽

1973 ◽

Vol 31 ◽

pp. 428-429

Author(s):

C. W. Kischer

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Proliferation ◽

Fine Structure ◽

Metabolic Activity ◽

Hypertrophic Scar ◽

Normal Skin ◽

Ground Substance ◽

Hypertrophic Scars ◽

Scanning Electron

The morphology of the fibroblasts changes markedly as the healing period from burn wounds progresses, through development of the hypertrophic scar, to resolution of the scar by a self-limiting process of maturation or therapeutic resolution. In addition, hypertrophic scars contain an increased cell proliferation largely made up of fibroblasts. This tremendous population of fibroblasts seems congruous with the abundance of collagen and ground substance. The fine structure of these cells should reflect some aspects of the metabolic activity necessary for production of the scar, and might presage the stage of maturation.A comparison of the fine structure of the fibroblasts from normal skin, different scar types, and granulation tissue has been made by transmission (TEM) and scanning electron microscopy (SEM).

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The Effect of Androgen Depletion and Replacement on the Epithelium of the Seminal Vesicle of the Aging Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116577 ◽

1975 ◽

Vol 33 ◽

pp. 590-591

Author(s):

Venita F. Allison

Keyword(s):

Cell Proliferation ◽

Seminal Vesicle ◽

Male Rats ◽

Target Cells ◽

Cell Regeneration ◽

Secretory Function ◽

Electron Microscopic ◽

Aging Rat ◽

Microscopic Studies ◽

Androgen Depletion

In 1930, Moore, Hughes and Gallager reported that after castration seminal vesicle epithelial cell atrophy occurred and that cell regeneration could be achieved with daily injections of testis extract. Electron microscopic studies have confirmed those observations and have shown that testosterone injections restore the epithelium of the seminal vesicle in adult castrated male rats. Studies concerned with the metabolism of androgens point out that dihydrotestosterone stimulates cell proliferation and that other metabolites of testosterone probably influence secretory function in certain target cells.Although the influence of androgens on adult seminal vesicle epithelial cytology is well documented, little is known of the effect of androgen depletion and replacement on those cells in aging animals. The present study is concerned with the effect of castration and testosterone injection on the epithelium of the seminal vesicle of aging rats.

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Acetaminophen: Macula densa hypersecretory activity by induced hepatotoxicity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012895x ◽

1987 ◽

Vol 45 ◽

pp. 934-935

Author(s):

S.S. Poolsawat ◽

C.A. Huerta ◽

S.TY. Lae ◽

G.A. Miranda

Keyword(s):

Cell Proliferation ◽

Liver Function ◽

Chronic Inflammation ◽

Foam Cell ◽

Term Effect ◽

Short Term ◽

Drug Induced ◽

Experimental Induction ◽

Tissue Alterations ◽

Toxic Responses

Introduction. Experimental induction of altered histology by chemical toxins is of particular importance if its outcome resembles histopathological phenomena. Hepatotoxic drugs and chemicals are agents that can be converted by the liver into various metabolites which consequently evoke toxic responses. Very often, these drugs are intentionally administered to resolve an illness unrelated to liver function. Because of hepatic detoxification, the resulting metabolites are suggested to be integrated into the macromolecular processes of liver function and cause an array of cellular and tissue alterations, such as increased cytoplasmic lysis, centrilobular and localized necroses, chronic inflammation and “foam cell” proliferation of the hepatic sinusoids (1-4).Most experimentally drug-induced toxicity studies have concentrated primarily on the hepatic response, frequently overlooking other physiological phenomena which are directly related to liver function. Categorically, many studies have been short-term effect investigations which seldom have followed up the complications to other tissues and organs when the liver has failed to function normally.

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