Activation of Transcription Factor Nrf2 in HeLa Cells under the Action of Nitrosyl Iron Complex with N-Ethylthiourea.

We studied the effect of an NO donor, nitrosyl iron complex with N-ethylthiourea, on Nrf2-dependent antioxidant system activation of tumor cells in vitro. The complex increased intracellular accumulation of Nrf2 transcription factor and induced its nuclear translocation. It was shown that both heme oxygenase-1 gene and protein expression increased significantly under the influence of the complex. Nrf2 activation was accompanied by a decrease in the intracellular accumulation of proinflammatory transcription factor NF-κB p65 subunit and expression of its target genes. The cytotoxic effect of N-ethylthiourea leads to induction of Nrf2/HO-1 antioxidant response and suppression of NF-κB-dependent processes in tumor cells.

Effect of Pyridoxine Derivative B6NO on Transcription Factor Nrf2 Activity and Cytotoxic Properties of Doxorubicin In Vitro.

The effect of a new pyridoxine derivative B6NO on doxorubicin cytotoxicity and Nrf2-dependent cellular processes in vitro was studied. Antioxidant B6NO enhances the cytotoxic effect of doxorubicin on tumor cells, which is associated with G2/M cell division arrest and an increase in activity of proapoptotic enzyme caspase-3. The antioxidant promotes intracellular accumulation and nuclear translocation of Nrf2 transcription factor in non-tumor and tumor cells. In non-tumor cells, B6NO increases the expression of antioxidant system proteins and reduces ROS generation in the presence of doxorubicin. In tumor cells, no activation of Nrf2-dependent processes occurs under the action of the antioxidant. Our findings demonstrate the prospect of further studies of pyridoxine derivatives as antioxidants to reduce adverse reactions during chemotherapy.

Cationic dinitrosyl iron complexes with thiourea exhibit selective toxicity to brain tumor cells in vitro.

The cytotoxic activity of a series of dinitrosyl iron complexes (DNICs) with thioureas against cells of different origin has been studied in this work. The cytotoxicity of the studied DNICs proved to be substantially different depending on the structure of the complexes and cell line. Complexes with thiourea and 1,3-dimethylthiourea were found to induce notable cell death in different cell lines of both cancerous and non-cancerous origin, while the N-ethylthiourea-bearing complex induced cell death in cells derived from brain tumors. The studied DNICs effectively release NO while decomposing in solutions, as follows from the electrochemical analysis. It was found that the cytotoxic effects of the studied DNICs did not correlate with their NO-donating ability, hence suggesting that their cytotoxic activity is, in a big part, defined by the long-lived nitrosyl iron-sulfur intermediates formed during the decomposition of the complexes. The structures of the products formed upon hydrolytic decomposition of all studied DNICs have been studied by electrospray ionization mass spectrometry. Stable high-molecular cluster ions containing NO groups namely [Fe4S3(NO)7]- (Roussin's "black salt" anion), [Fe4S3(NO)5]-, [Fe4S4(NO)4]-, [Fe4S3(NO)4]- and [Fe4S3(NO)6]- have been detected in the solution of the N-ethylthiourea-bearing complex. The mechanism of Roussin's "black salt" anion formation in a solution of DNIC with N'-ethylthiourea was studied using density functional theory. This moved us near understanding the reasons for the formation of biologically active intermediates upon the decomposition of the complex with N'-ethylthiourea, which are apparently responsible for the unique antiglioma activity of the complex.

[Influence of the L-carnitine and resveratrol complex on physiological, biochemical and morphological indicators of normal and obese rats].

Specialized products and dietary supplements, enriched with complexes of minor biologically active substances (BAS), are often offered as components of therapeutic diets in the treatment of obesity and metabolic syndrome. At the same time, the possible effects of the interactions of BAS when consuming a multicomponent product have not been studied enough. The aim - to study the action on rats' organism of a complex supplement (RС), containing resveratrol (Res) and L-carnitine (L-Car), when consumed with a standard balanced or hypercaloric diet. Material and methods. Male Wistar rats received for 63 days a standard balanced diet (SD) or a high-fat-high-carbohydrate diet (HFCD) with an excess of total fat (30%) and fructose (20% solution instead of drinking water), or the same diets supplemented with RС in a low (25 mg/kg body weight as Res and 300 mg/kg body weight as L-Car) or high (50 and 600 mg/kg body weight, respectively) doses. The muscle grip strength, behavioral reactions in tests of the conditioned passive avoidance reflex (CPAR) and elevated plus maze (EPM) were studied. At the end of the experiment, the mass of adipose tissue and internal organs was determined together with the activity of microsomal and cytosolic liver enzymes for specific substrates, plasma biochemical parameters, liver morphology by lightoptical microscopy, accumulation of lipofuscin-like granules (LLG) in the liver and kidneys by laser confocal microscopy. Results. In the rats fed HFCD, compared with SD, there was an increase in the mass index of liver, total inguinal and retroperitoneal white adipose tissue, in the levels of glucose and triglycerides, in the activity of hepatic CYP1A1 and CYP3A monooxygenases, UDPglucuronosyltransferase, heme oxygenase, and simultaneous decrease of high and low density lipoprotein cholesterol, and quinone oxidoreductase activity. The RС intake stimulated the locomotor activity of rats in EPM, however, this effect was less pronounced against the background of HFCD consumption. In rats consuming SD (but not HFCD), the addition of RС caused an increase in search activity and anxiety according to the EPM and CPAR data. The effect on short- and long-term memory retention was statistically insignificant. RС intake did not have hypolipidemic and hypoglycemic properties but caused in low dose an increase in the ratio of the activity of transaminases AST/ALT in animals fed HFCD. The liver CYP3A activity increased in rats supplemented with RС in high dose fed HFCD. In the kidneys of animals, the consumption of RС resulted in increased accumulation of LLG. Conclusion. When studying the effect of the complex supplement RС on normal and obese rats according to the studied physiological, morphological and biochemical indexes, no positive effects were revealed, that would not have manifested themselves for Res and L-Car separate intake. No evidence of synergistic action of L-Car and Res were found, and some of the effects of the complex supplement can be considered as adverse. This requires careful assessment when combined using these substances in complex diet therapy of metabolic disorders in humans.

[Audiological profile of patients with SARS-Co-V-2 PCR-positive cases]. / Audiologicheskii profil' patsientov pri zabolevanii, vyzvannom virusom SARS-CoV-2.

COVID-19 is a new pandemic caused by a novel coronavirus, SARS-CoV-2. COVID-19 has spread throughout China and received worldwide attention. On 11 February 2020, World Health Organization (WHO) officially declared COVID-19. The clinical symptoms of COVID-19 patients may vary, more often include symptoms affected by upper and lower respiratory tract damage. In ENT practice it is used to mention rhinitis, sore throat, anosmia/hyposmia. The effect of COVID-19 is an interesting issue in audiology. There were 78 patients who were confirmed positive for COVID-19 PCR-positive cases and 30 normal non-infected subjects in our study. The patients were divided into two groups according to severity their clinical symptoms from asymptomatic COVID-19 PCR-positive cases to severe form. All patients underwent audiological evaluation included tympanometry, acoustic threshold and transient evoked otoacoustic emission (TEOAE). Although hearing sensitivity was normal among some participants, it was statistically proved that TEOAEs could pick up subtle deterioration in the outer hair cells functions and impact on the cochlear.

Nrf2-Dependent Expression of Glutathione Antioxidant System Genes and Redox Status in Cells of In Vivo Drug-Resistant Murine P388 Leukemia Strains.

We measured the content of ROS and malondialdehyde in cells of in vivo drug-resistant murine P388 leukemia strains. It was found that the strains did not differ by malondialdehyde concentration, but intracellular concentration of ROS in cells of the cyclophosphamide-resistant strain (P388/CP) was higher than in cells of the original (P388) and other studied strains (P388/Rub, P388/cPt). Nuclear localization of the transcription factor Nrf2 in cells of strain P388/CP attested to its constitutive activation. Enhanced relative expression of the GCLM gene was found in all studied drug-resistant strains; the expression of the GSR and GPX1 genes was increased only in cells of the cyclophosphamide-resistant strain. These findings suggest that the mechanism of resistance of strain P388/CP is associated with increased activity of glutathione metabolism that developed as a result of activation of the antioxidant response transcription factor Nrf2 against the background of high intracellular concentration of ROS.

Influence of Tumor Suppressor p53 Functioning on the Expression of Antioxidant System Genes under the Action of Cytotoxic Compounds.

The effect of inhibition of the tumor suppressor p53 on the antioxidant system genes expression under the influence of cytotoxic compounds of the platinum group was studied. It was found that the action of platinum(II) and platinum(IV) complexes induced accumulation of p53 protein with a maximum in 12 h, which was confirmed by an increase in the expression of the P21 gene, the target gene of the p53 protein. It was shown that the action of platinum complexes activated the expression of catalase and superoxide dismutase 2 genes. Suppression of p53 protein functions with specific inhibitor α-piphitrin under the action of platinum complexes reduced the expression of catalase and superoxide dismutase 2 genes and the target gene P21, which attested to the p53-dependent regulation of these genes.

Comparative Whole-Transcriptome Profiling of Liver Tissue from Wistar Rats Fed with Diets Containing Different Amounts of Fat, Fructose, and Cholesterol.

Differential expression of 30,003 genes was studied in the liver of female Wistar rats fed with isocaloric diets with the excess of fat, fructose, or cholesterol, or their combinations for 62 days using the method of whole-transcriptome profiling on a microchip. Relative mRNA expression levels of the Asah2, Crot, Crtc2, Fmo3, GSTA2, LOC1009122026, LOC102551184, NpY, NqO1, Prom1, Retsat, RGD1305464, Tmem104, and Whsc1 genes were also determined by RT-qPCR. All the tested diets affected differently the key metabolic pathways (KEGGs). Significant changes in the expression of steroid metabolism gene were observed in the liver of animals fed with the tested diets (except the high-fat high fructose diet). Both high-fat and high-fructose diets caused a significant decrease in the expression of squalene synthase (FDFT1 gene) responsible for the initial stage of cholesterol synthesis. On the contrary, in animals fed with the high-cholesterol diet (0.5% cholesterol), expression of the FDFT1 gene did not differ from the control group; however, these animals were characterized by changes in the expression of glucose and glycogen synthesis genes, which could lead to the suppression of glycogen synthesis and gluconeogenesis. At the same time, this group demonstrated different liver tissue morphology in comparison with the animals fed with the high-fructose high-fat diet, manifested as the presence of lipid vacuoles of a smaller size in hepatocytes. The high-fructose and high-fructose high-fat diets affected the metabolic pathways associated with intracellular protein catabolism (endocytosis, phagocytosis, proteasomal degradation, protein processing in the endoplasmic reticulum), tight junctions and intercellular contacts, adhesion molecules, and intracellular RNA transport. Rats fed with the high-fructose high-fat or high-cholesterol diets demonstrated consistent changes in the expression of the Crot, Prom1, and RGD1305464 genes, which reflected a coordinated shift in the regulation of lipid and carbohydrate metabolisms.

Activity of Antioxidant Enzymes and Content of Reduced Glutathione in Cells of Drug-Resistant Murine Leukemia P388 Strains.

Activities of superoxide dismutase and catalase and content of reduced glutathione in cells of drug-resistant murine leukemia P388 strains were studied without or after administration of antitumor compounds. In the absence of chemotherapeutic agents, no significant differences in activities of the studied enzymes in cells of the initial strain and strains resistant to cyclophosphamide, cisplatin, and rubomycin were observed. Compounds to which resistance was developed did not significantly affect activity of enzymes in cells of drug-resistant strains, while the use of compounds that were not resistance inductors was accompanied by a significant decrease in enzyme activity in cells resistant to cisplatin and rubomycin. In cells of strains resistant to cisplatin and cyclophosphamide, the content of reduced glutathione significantly differed from that in the initial strain. In addition, the concentration of reduced glutathione in cells of cyclophosphamide-resistant strain considerably decreased upon addition of the drug producing a therapeutic effect. Our findings suggest that the mechanism of resistance of in vivo derived cyclophosphamide resistant cell strain is related to increased level of reduced glutathione and activity of its metabolism.

Effect of Chitosan-(Poly)Nitroxides on Normal and Tumor Cells under Conditions of Induced Oxidative Stress.

The cytotoxicity and antioxidant effects of chitosan-(poly)nitoxides of different molecular weights containing a nitroxide radical of the piperidine structure were studied on tumor (HeLa, A172, and HepG2) and normal (Vero) cell lines. The chitosan-(poly)nitroxides exhibited low cytotoxicity. Under conditions of oxidative stress induced with tert-butyl hydroperoxide, the most pronounced decrease in ROS levels in the presence of chitosan-(poly)nitroxides was observed in normal cells. In cell homogenates, the decrease in malondialdehyde levels was observed only in the presence of low-molecular-weight chitosan-(poly)nitroxide irrespective of the cell line. Our data demonstrate that the cell-specific antioxidant properties of chitosan-(poly)nitroxides are related to their penetration into cells and interaction with intracellular membranes.

[Sex and line differences in biochemical indices and fat soluble vitamins sufficiency in rats on in vivo model of metabolic syndrome].

Consumption of diets that are inadequate in energy value to the actual energy expenditure can lead to the development of metabolic syndrome (MS), which has consequences such as type 2 diabetes mellitus, non-alcoholic steatohepatosis, atherosclerosis, gout, allergic diseases. Experimental models of MS are needed to develop new approaches to its dietary and drug correction. The aim of the work was a comparative analysis of functional, biochemical and vitamin markers characterizing the effect of a diet with a high content of fructose (F) on males and females of various rat lines and the selection on this basis of an optimal in vivo MS model. Male and female rats of the outbred Wistar line (W) and the inbred Dark Agouti line (DA) were used in the work number of 16 individuals of each sex and line. The animals of the 1st (control) groups of each sex and line received a balanced semi-synthetic diet according to AIN93, and the animals of the 2nd (experimental) groups - the same diet and 30% solution of F instead of water in the regime of free access. Within 121 days, energy value of diets consumed, the increase in body weight and blood pressure were determined; relative mass of internal organs, biochemical parameters of blood plasma, content of fat-soluble vitamins A and E in blood plasma and liver were determined at withdrawal of animals from experiment. It was shown that, in spite of the increased energy value of the diet in the experimental groups throughout experiment, DA males and females practically did not respond to this by an increase in body weight gain, in contrast to W rats (in particular, females). Consumption of diets with F led to an increase in glucose level irrespective of gender and line, whereas triglyceride level (TG) significantly increased only in the case of W female. Addition of F caused in DA rats of both sexes an increase in the mass of the kidneys, as well as more pronounced, in comparison with W rats manifestation of markers of toxic effects on the liver (increases alanine aminotransferase and γ-glutamyltransferase activity, elevated urea and bilirubin level in blood plasma). In rats of both lines intake of F suppressed the accumulation of retinol palmitate in the liver in terms of its specific content. The total content of α-tocopherol in liver was significantly higher in W compared with DA. At the same time, α-tocopherol levels in blood plasma correlated with TG, and the α-tocopherol/TG ratio significantly decreased in female W receiving F, which were characterized by hyperlipidemia. Thus, the effect of F on W males and, in particular, females, basically corresponded to the classical picture of MS with body weight increasing, elevated blood pressure, glycemia and TG increase, whereas the toxic effect of F prevailed in DA liver and, possibly, kidneys without development of marked dyslipidemia and obesity.

[Effects of quercetin on protective capacity in rats fed a high-fructose diet].

The purpose of the study was to determine effects of quercetin on protective capacity parameters in the experiment on rats fed a high fructose diet. Rats of the control group received a semi-synthetic (s/s) diet and water; animals from the 1st experimental group - s/s diet and 20% fructose solution instead of drinking water; rats of the 2nd experimental group- s/s diet with quercetin (0.1% indiet) and 20% fructose solution instead of drinking water for 20 weeks. Parameters of antioxidant status [total antioxidant activity (AOA), the content of malondialdehyde (MDA) and lipids hydroperoxides, the level of reduced and oxidized glutathione, activity of superoxide dismutase, catalase, glutathione peroxidase, paraoxonase-1, hemeoxygenase-1, NAD(P)H-quinone oxidoreductase], the activity of xenobiotic-metabolizing enzymes [CYP1A1, CYP1A2, CYP2B1, CYP3A, UDP-glucuronosyltransferase (UDP-GT) and glutathione transferase] were studied in plasma and liver of rats. Consumption of the high-fructose diet led to changes in some parameters: diminution of AOA in blood plasma, decrease of AOA and MDA level, unsedimentable activity of lysosomal enzymes, increase of the UDP-GT activity in liver. The inclusion of quercetin in the diet did not affect the studied parameters, except for a more pronounced decrease of the unsedimentable activity of lysosomal enzymes in rat liver. The results of the study indicated that there was no significant effect of quercetin on the protective capacity of rats at the initial stage of obesity caused by high-fructose diet.

[The mechanism of stimforte action on herpesvirus infection.]

Increased protease activity and a significant amount of granzyme B were observed in in organs of mice infected with acute herpes simplex virus HSV-1 with the introduction of Stimforte (100 or 250 µg/mouse). Thus, this drug activates killer cells, which play an extremely important role in the suppression of HSV-1 infection. Although the administration of Stimforte (100 µg/mouse) to intact mice results in the activation of IFN-ß production and does not activate the production of IFN-λ, Stimforte administration to animals infected with HSV-1 reduces production of IFN-ß in serum, brain and lungs, whereas the production of IFN-λ considerably increases as the result of administration of 100 µg/mouse of Stimforte.

Biochemical and Morphological Parameters of Inbred/Outbred Lines and DBCB Tetrahybrid Mouse in High-Sugar In Vivo Model of Metabolic Syndrome.

Integral, biochemical, and morphological parameters and concentrations of vitamins, particularly lipid soluble vitamins, were analyzed in female mice of inbred DBA/2J line, outbred ICR-1 (CD-1) line, and DBCB tetrahybrid mice on the in vivo model of metabolic syndrome induced by consumption of 30% sucrose for 2 days. In contrast to inbred and outbred lines, DBCB tetrahybrid mice developed abdominal obesity, hypercholesterolemia, and pronounced morphological picture of fatty liver disease. The lipid-coupled transport of vitamin E to the liver is also enhanced in these animals, which compensated decreased supply of vitamin E to the liver under conditions of high-sugar ration. The observed interstrain differences can be related to genetic features of the used mouse lines and DBCB tetrahybrid mice and require further genomic, transcriptomic, proteomic, and morphological studies. The results of the study based on the in vivo model of metabolic syndrome allow identifying the key biomarkers for complex diagnostics and prognosis of metabolic syndrome complications, such as nonalcoholic steatosis of the liver.

Neuromotor Activity, Anxiety and Cognitive Function in the In Vivo Model of Alimentary Hyperlipidemia and Obesity.

Behavioral indicators characterizing specific features of the pathological process of alimentary-dependent diseases were studied using in vivo model of alimentary hyperlipidemia in rats and mice. Rats and mice of the control groups received balanced semisynthetic diet for 63 days; animals of the experimental groups received a diet with high fat content (30% dry weight), balanced or high-fat diet with fructose solution instead of water, balanced cholesterol-enriched diet (0.5% dry weight), or balanced cholesterol-enriched diet with fructose solution. During the experiment, the mass of food, consumed by the animals, was monitored daily. Muscle tone was assessed by the front paw grip strength on days 33 and 54 of the experiment. Anxiety was tested in the elevated plus maze on days 36 and 57. Behavior and memory were assessed by conditioned passive avoidance reflex on days 39, 40, and 61. A significant increase in muscle tone was revealed on day 54 in rats fed with a balanced diet with fructose, and in mice, that received a similar diet, supplemented with fructose and cholesterol. Anxiety in the second test (day 57) was significantly decreased in rats fed high-fat diet and increased in mice fed high fat diet and high fat diet with fructose. In the second test, additional amount of cholesterol in the diet was the factor that significantly improved both short-term and long-term memory in both species. In mice, in contrast to rats, addition of fructose, including combination with high-fat diet, significantly worsened short-term and long-term memory. Thus, dietary factors, contributing to alimentary dyslipidemia development in rats and mice, can significantly affect the indices of neuromotor activity, anxiety level and cognitive functions, and the nature and direction of these changes are largely species-specific.

Different effects of the immunostimulatory drug Stimforte on infections of hepatitis C virus and herpes simplex virus type 1.

Stimforte, an immune response-stimulating preparation, is active with respect to hepatitis C virus (HCV) and herpes simplex virus type I (HSV-1). The effects of Stimforte in animals infected with either HCV or HSV-1 are fundamentally different. In mice with acute herpes virus infection, Stimforte administration leads to a higher activity of natural killer cells and cytotoxic lymphocytes, and the amount of interferon (IFN) λ grows. In mice infected with HCV, Stimforte administration results in a significant increase in IFN-ß but not IFN-λ in blood and affected organs. Stimforte has been found to affect directly HCV reproduction that causes the infected cell death, but it does not affect HSV-1 reproduction in the Vero cells (V).

[Comparative evaluation of vitamin status and biochemical markers of metabolic syndrome on the models of rodents receiving rations with high quotas of different sugars].

Metabolic syndrome (MS) is one of the leading causes of non-infectious pathology among the population of developed countries. It is necessary to have experimental in vivo models of MS for pre-clinical testing of new approaches to its dietary therapy. The purpose of the study was a comparative analysis of functional, biochemical and vitamin markers that characterize the effect of diets with different composition of simple carbohydrates (sugars) on female Wistar rats and female C57Black/6J mice. Animals of each species (n=80) were divided into 5 groups of equal numbers. The animals of the 1st (control) group received a balanced semi-synthetic diet, and the animals of groups from the 2nd to the 5th - the same diet and 30% solutions of sugars - glucose (Gl), fructose (Fr), equimolar mixture Gl and Fr and sucrose instead of water, in the regime of free access for up to 133 days. Measured values included blood pressure, mass of internals, biochemical parameters of blood plasma, the activity of CYP1A1, CYP1A2, CYP2B1, CYP3A and glutathione transferase (GT) in liver, glutathione peroxidase (GP) in erythrocytes, the content of vitamins A and E in blood plasma and in liver, the level of vitamins B1 and B2 and nicotinamide coenzymes in liver. Interspecific differences in the response to sugars manifested in a decrease in the solid diet consumption in mice (in contrast to rats), so that the total consumed energy value in experimental groups of mice did not differ systematically from control, and the weight gain was reduced. Liver was the most sensitive organ to addition of sugars in both rats and mice with mass significantly increasing by the 2nd and the 4th months of the experiment. Hyperglycemia and triglyceridemia were the most noticeable in rats receiving Fr. The concentration of phosphorus increased significantly in blood plasma of all rats groups that received sugars. In rats there was a decrease in the activity of CYP1A1 and CYP1A2 in groups 3 and 5, the activity of CYP2B1 in groups 2 and 5, the increase in HT activity in groups 2, 4 and 5, and GP in group 3 at 56th day of experiment. There was a significant decrease in this index in group 3 at the 56th and the 133rd days of the experiment, and in groups 4 and 5 - at the 56th day. Plasma tocopherol to triglycerides ratio decreased in rats of group 3 at the 56th and 133rd days, groups 4 и 5 - at 56th day, which indicated the decrease of vitamin E safety. Sugars consumption suppressed retinol palmitate accumulation in the liver of rats and mice, and alpha-tocopherol in mice. It was concluded that Fr had the greatest effect on the studied indicators of the organism, and the rats showed the most significant similarity with the clinical picture of MS.

[The influence of separate and combined supplementation with curcumin and quercetin on the protective capacity in rats].

The purpose of the study was to determine the effects of curcumin (CUR) and quercetin (QUER) on the expression of genes and activity of prototypical Nrf2/ARE- and AhR/ XRE-regulated enzymes. Investigation was carried out on male Wistar rats with initial body weight (230-235 g b.w.) that received for 14 days CUR (200 mg/kg b.w.) and QUER (200 mg/kg b.w.) separately or in combination within the standard semi-synthetic diet. The expression of genes and activity of Nrf2/ARE - regulated enzymes - heme oxygenase- 1(HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1), AhR/XRE-regulated CYP1A1, CYP1A2 enzymes and the mRNA level of transcription factors Nrf2 and AhR were determined in rats liver. Also the expression of gene CYP3A1 and activity of CYP3A, UDP-glucuronosyltransferase, glutathione transferase were studied in rats liver. Along with this the total antioxidant activity (AOA), malondialdehyde and lipid hydroperoxides levels were determined in blood plasma and liver. The reduced and oxidized glutathione level, total and unsedimentable activity of lysosomal enzymes were investigated in rats' liver. QUER, especially in combination with CUR, increased the AOA of blood plasma and reduced the content of lipid hydroperoxides in it. CUR and QUER did not affect NQO1 activity, but the combined action caused an increase in the HO-1 activity without affecting the expression of the corresponding gene (Hmox1) and Nrf2 gene. CUR and, to a lesser extent QUER, had a strong inducing effect on CYP1A1, CYP1A2, CYP3A activity, but only the CYP1A1 activation was accompanied by the induction of CYP1A1 gene. The inducing effect of CUR and QUER on the activity of CYP450 enzymes greatly enhanced by their combined action. Membrane stabilizing action of CUR and QUER was also strongly expressed under its combined intake. Thus, we can conclude that CUR and QUER, especially in combination, contribute to the protective and adaptive capacity.

Effect of Cytotoxic Compounds on Activity of Antioxidant Enzyme System in MCF-7 and H1299 Cells.

We studied the function of the antioxidant system in tumor cell lines MCF-7 and H1299 that differ by the state of tumor suppressor gene p53. Exposure to different classes of cytotoxic compounds induced several types of antioxidant system responses that depend on the type of cell line. The effects of platinum(II) and platinum(IV) complexes on activity of antioxidant enzymes vary, which can be explained by differences in their accumulation and biotransformation in tumor cells. Triazole and oxazolidinone derivatives had little effect on activity of superoxide dismutase and catalase in H1299 cells, but increased superoxide dismutase activity in MCF-7 cells.

[Effect of rutin and hesperidin on the expression of Nrf2 gene and the activity of hemoxygenase-1 and NAD(P)H-quinone oxidoreductase at their separate and combined action].

Flavonoids rutin (R) and hesperidin (Hes) have a broad spectrum of the biological activity based on their antiradical properties and ability to increase the activity of antioxidant enzymes, including the activity of heme oxygenase-1 (HO-1) and NAD(P)H-quinone oxidoreductase (QR). It is supposed that the main regulator of the activity of HO-1 and QR is the transcription factor Nrf2. The purpose of the study was to determine the effects of R and Hes on the expression of Nrf2 gene and protein, on the activity and mRNA and protein expression of HO-1 and QR at their separate and combined action. Administration in diet of male Wistar rats (with initial body weight 180-200 g) R (400 mg/kg b.w.) and Hes (400 mg/ kg b.w.) during 14 days separately or in combination had no toxic or pro-oxidant effect, which were assessed by the level of liver MDA, hydroperoxides of lipids, reduced and oxidized glutathione. R and, to a lesser extent, Hes caused increased activity of HO-1 and QR. Their combined effect on the activity of HO-1 did not differ from the separate effect of each flavonoid. The combined action of R and Hes on the activity of QR was additive. According to Western blotting, changes in HO-1, Nrf2 and QR protein levels under the action of R and Hes separately or in combination were not statistically significant. The results of real time PCR demonstrated the presence of small, but statistically significant, changes in the level of expression of the genes Nrf2 (Nrf2), HO-1 (Hmox1) and QR (NQO1) both for separate and combined action of R and Hes. Thus, the obtained results showed that high-dose of R and Hes separately and in combination didn't significantly affect the gene and protein expression of transcription factor Nrf2 and that the increased activity of HO-1 and QR was not associated with the increased expression of Hmox1 and NQO1 genes.