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Tripeptide GSH is associated not only with the control and maintenance of redox cell homeostasis, but also with the processes of detoxification, proliferation, cell differentiation, and regulation of cell death. Disruptions in GSH synthesis and changes in the GSH/GSSG ratio are common for many pathological conditions, including malignant neoplasms. Numerous data indicate the importance of GSH and the GSH/GSSG ratio in the regulation of tumor cell viability, in the initiation of tumor development, progression, and drug resistance. However, control of the mechanism of GSH synthesis in malignant tumors remains poorly understood. This review discusses the features of GSH synthesis and its regulation in tumor cells. The role of GSH in the mechanisms of apoptosis, necroptosis, ferroptosis, and autophagy is considered.

Over the last decade fundamentally new features have been revealed for the participation of glutathione and glutathione-dependent enzymes (glutathione transferase and glutaredoxin) in cell proliferation, apoptosis, protein folding, and cell signaling. Reduced glutathione (GSH) plays an important role in maintaining cellular redox status by participating in thiol-disulfide exchange, which regulates a number of cell functions including gene expression and the activity of individual enzymes and enzyme systems. Maintaining optimum GSH/GSSG ratio is essential to cell viability. Decrease in the ratio can serve as an indicator of damage to the cell redox status and of changes in redox-dependent gene regulation. Disturbance of intracellular GSH balance is observed in a number of pathologies including cancer. Consequences of inappropriate GSH/GSSG ratio include significant changes in the mechanism of cellular redox-dependent signaling controlled both nonenzymatically and enzymatically with the participation of isoforms of glutathione transferase and glutaredoxin. This review summarizes recent data on the role of glutathione, glutathione transferase, and glutaredoxin in the regulation of cellular redox-dependent processes.

We studied the effect of quercetin on ovarian adenocarcinoma SKOV-3 cell line and isogenic subline SKOV-3/CDDP resistant to the anticancer drug cisplatin. It was found that in resistant cells, quercetin in a concentration of 100 μM that causes a decrease in the cell viability suppressed the expression of genes encoding the key antioxidant enzymes ( SOD2 , CAT , GPX1 , and HO-1 ), transcription factor Nrf2, and kinases of the PI3K/Akt/mTOR signaling pathway. In parental cells, quercetin, on the contrary, increased the expression of these genes. The results confirm the redox-dependent regulation induced by quercetin and its opposite nature in cisplatin-sensitive and cisplatin-resistant cancer cells.

This paper presents a study of nonaqueous suspensions based on ZrO 2 –8 mol % Y 2 O 3 (8YSZ) powders and describes the use of the powders for producing thin-film coatings on a La 2 NiO 4 (LNO) substrate by electrophoretic deposition (EPD). Stable suspensions for EPD have been prepared using 8YSZ powders differing in morphology and particle size: nanopowder (YSZ_L) produced by a laser evaporation–condensation process and commercially available powder (YSZ_T) (Tosoh, Japan). Ultrasonic processing has been found to have different effects on the particle size composition of the YSZ_L and YSZ_T suspensions. The two types of suspension have been shown to differ significantly in the kinetics of the deposition current at constant voltage: during deposition from the YSZ_L suspension, the current was observed to rise, whereas in the case of the YSZ_T suspension the current decreased markedly with deposition time. The YSZ_L film has been shown to be denser than the YSZ_T film. After sintering at 1350°C, it consisted of completely formed grains ranging in size from 1 to 5 μm. To remove surface pores in YSZ_T coatings, they should be sintered at a temperature of 1450°C.

The effect of curcumin on the resistance of SKOV-3 human ovarian adenocarcinoma cells to cisplatin was studied. It was found that curcumin induced “reversal” of cancer cells resistance, which was associated with suppression of the expression of genes encoding the key antioxidant enzymes ( SOD1 , SOD2 , CAT , GPX1 , and HO-1 ) and transcription factor Nrf2 and a decrease in the expression of genes encoding kinases of the PI3K/Akt/mTOR signaling pathway. The obtained results confirm the role of redox-dependent regulation in the “reversal” of cancer cells resistance to cisplatin.

We compared the content of extracellular genomic and mitochondrial DNA (ec-gDNA and ec-mtDNA) in the follicular fluid (FF) of women after using two types of triggers for final oocyte maturation: human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone agonist (GnRHa). The study included 43 women aged 21-35 years with preserved ovarian reserve according to hormonal profile and ultrasound examination, who were divided into two groups depending on the type of trigger: hCG at a dose of 10,000 IU (group 1; n = 30) and GnRHa at a dose of 0.2 mg (group 2; n = 13). From each patient, a sample of FF was obtained during transvaginal puncture from a dominant follicle without blood admixture. The content of ec-gDNA and ec-mtDNA was measured by qPCR. At the first stage, a positive correlation was found between the content of ec-gDNA and ec-mtDNA and the level of anti-Müllerian hormone, as well as between the level of ec-mtDNA and the number of oocytes. In patients reveiving GnRHa, the level of ec-mtDNA was significantly higher. There were no significant differences between the groups in the level of free ec-gDNA. The identified differences in ec-mtDNA in FF not only indicate different mechanisms of action of the used drugs, but also offer hope for the development of more precise approaches to the use of FF at the embryological stage of ART infertility treatment programs.

Cellular redox homeostasis involves a combination of redox processes and corresponding regulatory systems and represents an important factor ensuring cell viability. Redox-dependent regulation of cellular processes is a multi-level system including not only proteins and enzyme complexes, but also non-coding RNAs, among which an important role belongs to microRNAs. The review focuses on the involvement of miRNAs in the redox-dependent regulation of both ROS (reactive oxygen species)-generating enzymes and antioxidant enzymes with special emphasis on the effects of miRNAs on redox-dependent processes in tumor cells. The impact of ROS on the miRNA expression and the role of the ROS/miRNA feedback regulation in the cell redox state are discussed.

— The effect of isochronous annealing in vacuum at temperatures of 100–400°C on the forward and reverse current-voltage characteristics of Cr–SiC(4H) Schottky diodes is studied. Diodes of different sizes are manufactured using the same technology based on one lightly doped (~4 × 10 14 cm –3 ) epitaxial layer. The current-voltage characteristics are close to ideal in all cases, but their significant spread before annealing, a decrease in the spread, and a shift to the low-voltage region as a result of annealing at 400°C were found. It is assumed that the main diode is in all cases is shunted by a parasitic diode, the barrier height of which is reduced as a result of annealing.

The results of a study into the effect of irradiation with heavy Ar ions on the structural and optical characteristics of 4 H -SiC are presented. It is shown that even upon single-time irradiation with 53-MeV Ar ions at a fluence of 1 × 10 10 cm –2 there are at least two powerful local regions with negative deformation dominant in the structure of silicon carbide. Also, a region with positive deformation is observed in the structure. The formation of localized clusters with negative and positive deformations along with the undisturbed matrix gives rise to linear-type defects that partially relieve stresses in the structure. It is assumed that, upon irradiation with Ar ions, the resulting complex defect structure provides the effect of point-defect gettering and leads to a quantum efficiency of 4 H -SiC UV photodetectors that is comparable with that of the initial samples.

Forward and reverse current-voltage (IV) characteristics of Cr-SiC (4H) Schottky diodes based on epitaxial layers with doping (1-3)· 10 15 cm -3 were studied in the temperature range of 300-550 K. It is shown that in many cases the IV characteristics are close to ideal, but a significant spread of the forward IV characteristics of diodes manufactured in the same way on the same epitaxial layer was found, probably due to the spread of the Schottky barrier heights reaching 0.3 eV. Heating of the diode, as well as packaging, can also change the Schottky barrier height. An alternative explanation suggests the presence of a powerful shunt.