[Influence of the rat diet enrichment with oat ß-gucans on the assimilation of B group vitamins, mineral elements and lipid metabolism].

Despite the widespread use of oat ß-glucans as ingredient of foods and dietary supplements, there is insufficient data on their effect on the metabolism of vitamins and minerals. The purpose of the study was to evaluate the effect of including oat bran with a high content of ß-glucans (ß-glucan) in the diet on the absorption of micronutrients and lipid metabolism in growing rats deficient in vitamins D, group B and trace elements (iron, copper, zinc). Material and methods. After the development of micronutrient deficiency (for 23 days), in order to assess the effect of oat bran (5%) with a high content of ß-glucans on the correction of the micronutrient status of growing male Wistar rats (with initial body weight of 70.7±0.7 g), the missing micronutrients were introduced in the semi-synthetic diet deficient in vitamins D, group B, iron, copper and zinc within 7 days either along with ß-glucan (1.47%) or without its addition. Indicators of micronutrient sufficiency (riboflavin serum concentration, daily urinary excretion of thiamine, riboflavin and 4-pyridoxic acid, measured by fluorometric methods; serum concentration and urinary excretion of calcium, magnesium, iron, zinc, copper, phosphorus, measured by the atomic absorption method or using standard methods on a biochemical analyzer) and the biochemical parameters of blood serum were compared with the parameters of rats adequately provided with all micronutrients throughout the experiment. Results. Replenishment of missing micronutrients in the diet of rats with deficiency in vitamins D and group B, iron, copper and zinc for 7 days led to the elimination of deficiency of vitamins B1, B2 and B6, regardless of the presence of ß-glucans in the diet. At the same time, against the background of the presence of ß-glucans in the feed, an increase in the absorption of iron was observed, as evidenced by an increase by 1.73 times in iron blood plasma level (р<0.05) and a tendency towards its urinary excretion decrease by 1.60 fold (р<0.10) compared to animals from the control group. Adding oat bran with ß-glucans to the feed did not lead to a decrease in blood plasma level of total cholesterol and low-density lipoproteins cholesterol. The levels of high-density lipoprotein cholesterol and triglycerides in rats of all three groups did not have statistically significant differences. Conclusion. The presence of ß-glucans in the diet had virtually no effect on the absorption of B vitamins and improved the absorption of iron.

The Effect of Semi-Synthetic and High-Fat High-Carbohydrate Diets Containing Cholesterol on Lipid and Cholesterol Metabolism in Male Wistar Rats.

The choice of an optimal biological model of exogenous hypercholesterolemia is necessary for correct assessment of the cholesterol-lowering properties of bioactive substances and specialized food products and for validity of the experimental results. We studied the effects of cholesterol consumption in the composition of the standard semi-synthetic diet and high-fat high-carbohydrate diet for more than 3 months on lipid and cholesterol metabolism in male Wistar rats. Our findings suggest that cholesterol consumption in both diets led to a significant impairment of lipid and cholesterol metabolism, as well as an increase in insulin resistance in rats.

Systemic Biomarkers and Liver Morphology in Rats during Chronic Low-Dose Toxicant Administration against the Background of Vitamin Deficiency.

Liver morphology, intensity of apoptosis, and activity of xenobiotic metabolism enzymes were studied in a chronic model experiment in rats receiving a mixture of 6 pesticides against the background of life-long diets with adequate and insufficient supply of water-soluble vitamins. The dose of each pesticide in the mixture did not exceed the acceptable daily intake (1 ADI). It was found that chronic exposure to low doses of anthropogenic toxicants in combination with permanent vitamin deficiency provokes a number of liver changes, such as increased apoptosis activity, cytochrome P450 system depletion, steatosis, and inflammatory infiltration, which is a potential health risk factor.

[Influence of multiple insufficiency of vitamin D and B group vitamins, calcium and magnesium in the diet of rats on micronutrient sufficiency and plasma biochemical indicators].

The lack of vitamins D, B group, calcium and magnesium is common for the diet of the Russian population. It has been previously demonstrated that that the elimination of B vitamin deficiency is a necessary condition for the implementation of vitamin D biological functions. The aim of the research was to assess the effect of a combined deficiency of vitamins D and B group, calcium and magnesium in the diet of rats on biomarkers of micronutrient sufficiency and plasma biochemical indicators. Material amd methods. Male Wistar rats with an initial body weight of 66±1 g were randomly assigned to one of five groups. The rats of the 1st group (Control) were fed a standard semi-synthetic diet (SD) for 28 days. The combined deficit of vitamins D and B group, calcium and magnesium in rats of four experimental groups was caused by a 5-fold decrease in their content in the vitamin mixture and 2-fold decrease in their content in mineral mixture of the SD for 23 days. Over the next 5 days, the rats of 2nd group (+В+D+Ca+Mg) were fed a diet replenished for all missing vitamins and minerals, the rats of 3rd group (-В+D+Ca+Mg) were fed a diet with continued deficiency of B group vitamins, the rats of the 4th group (+В+D-Ca-Mg) were fed a diet with continued lack of calcium and magnesium, the diet of the 5th group (-B-D-Ca-Mg) was not replenished. Vitamins B1 and B2 in lyophilized liver and brain and urine, riboflavin in plasma and 4-pyridoxic acid in urine were determined by fluorimetric methods, 25(OH)D in plasma was determined by ELISA, the level of vitamins A and E in blood plasma and lyophilized liver, of vitamin E in whole brain - by HPLC. Biochemical parameters of blood plasma were determined using a biochemical analyzer. Results. In rats of the 5th group (-B-D-Ca-Mg), there were 3.4-fold increase (p<0.05) in iron plasma level, 1.7-fold elevation (p<0.10) in alkaline phosphatase activity, and 1.8-fold decrease (p<0.05) in alanine aminotransferase (ALT) activity on the background of the increase in α-tocopherol blood plasma level by 26.7% (p<0.05) and liver content by 2.0 fold (p<0.05) relative to the indicators in animals who hadn't passed the deficiency of micronutrients (Control) and / or from the 2nd group (+B+D+Ca+Mg). The lack of B group vitamins in the diet, which persisted during the correction of vitamin D, calcium and magnesium deficiency in rats of the 3rd group (-B+D+Ca+Mg), inhibited the recovery of diagnostically significant biochemical parameters of blood plasma (namely, an increased level of glucose, iron, triglycerides, cholesterol, α-tocopherol, increased alkaline phosphatase activity and reduced ALT activity) to the level in animals of the control group and/or rats fed the diet replenished for all missing micronutrients (+B+D+Ca+Mg). Conclusion. Combined deficiency of several micronutrients led to changes in biochemical blood parameters. Reduced intake of calcium and magnesium during the correction of the lack of vitamins D and B group in the diet can have a negative impact on vitamin B2 status. Even under normal dietary vitamin E intake the combined deficiency of several other micronutrients affected the metabolism of this vitamin (increased levels of vitamin E in the liver and blood plasma of animals). Chronic combined alimentary deficit of B vitamins, calcium and magnesium, which is characteristic in the diet of the Russian population, reduces vitamin D bioavailability, which justifies the expediency of using vitamin-mineral complexes.

[Pathogenetic mechanisms for the development of hematological disorders in induced fatty liver disease in Wistar rats and assessment of the regulatory effects of carnosine and α-lipoic acid].

The study of the relationship between hematopoiesis and metabolism is now particularly relevant in view of the high incidence of alimentary dependent diseases, including non-alcoholic fatty liver disease. In this regard, pathogenetic factors of this disease development are studied actively in order to choose adequate drug therapy and usage of bioactive substances with antioxidant properties. The aim of the study was to study the pathogenetic relationship of hematological disorders and imbalance of growth factors, leptin and ghrelin in male Wistar rats in the model of the initial stage of non-alcoholic fatty liver disease development and to assess the regulatory effect of minor bioactive substances - carnosine and α-lipoic acid. Material and methods. The studies were performed on male Wistar rats with initial body weight 150±10 g within 8 weeks. Animals were divided into 5 groups (n=8 in each). Rats of the control group received a complete modified diet AIN93M, in which soybean oil was replaced with sunflower oil and lard (1:1). Rats of the experimental groups consumed high-calorie choline-deficient diet (HCCDD), in which fat content was 45%, fructose content - 20% of the energy value of the diet. Rats of the 2nd group were fed HCCDD without any supplements, the 3rd group - with the addition of carnosine (75 mg/kg body weight), the 4th group - with the addition of α-lipoic acid (75 mg/kg body weight), the 5th group - with the combined addition of carnosine and α-lipoic acid in a total dose of 150 mg/kg body weight. Hematological values were determined on a hematological analyzer. The content of ghrelin and leptin, as well as growth factors GM-CSF and M-CSF in blood plasma and adipose tissue lysates, was determined by multiplex immunoassay using xMAP technology. Results. Rat intake of HCCDD resulted in decreased hemoglobin levels and red blood cell scores compared to controls. Diet enrichment with carnosine and α-lipoic acid did not have a reliable effect on these indicators. Carnosine intake had a protective effect on erythrocyte volume, a decrease of which was recorded in other experimental groups. HCCDD stimulated the growth of the absolute number of leukocytes in peripheral blood due to granulocytes and mononuclears. The enrichment of HCCDD with carnosine and α-lipoic acid led to a further increase in leukocytosis, the maximum level of which was observed in the group of rats fed HCCDD, simultaneously enriched with carnosine and α-lipoic acid (14.86±1.48×109/l compared to 8.67±1.23×109/l in control). All diets used in the research had no effect on the number of erythrocytes and platelets in the peripheral blood of rats. The use of both HCCDD alone and in combination with carnosine or α-lipoic acid intake had a negative effect on the level of growth factors GM-CSF and M-CSF in blood plasma and adipose tissue. The consumption of HCCDD caused an increase in leptin blood level (8.54±0.69 compared to 2.58±0.37 pg/ml in control, р<0.05), which was normalized by enriching the diet with carnosine and α-lipoic acid. Ghrelin blood level significantly decreased in all experimental groups compared to the control: by 30% in rats fed and by almost 50% when carnosine and α-lipoic acid were added to HCCDD. The intake of α-lipoic acid led to hormone level changes in adipose tissue lysates, leptin content decreased (2.31±0.11 vs 2.77±0.15 pg/ml), while ghrelin level significantly increased (0.35±0.14 vs 0.20±0.06 pg/ml), compared with the control group (р<0.05). Conclusion. The revealed interrelation of parameters of the cellular composition of peripheral blood and hemoglobin content with the changes in the content of GM-CSF, M-CSF, leptin and ghrelin in blood plasma and adipose tissue indicates the mutual influence of the studied CSF, leptin, ghrelin and added antioxidants (carnosine and α-lipoic acid) on the regulatory mechanisms of hematopoiesis in rats fed HCCDD.

[Effect of carnosine and α-lipoic acid on hepatocyte apoptosis and the cytokine profile in induced fatty liver disease in Wistar rats].

Non-alcoholic fatty liver disease (NAFLD) is now a common liver disease affecting about a third of the world's population. In this regard, the issue of studying the pathogenetic factors of the development of this disease in order to select adequate drug therapy and biologically active substances with antioxidant properties regulating the balance of pro- and anti-inflammatory cytokines is of particular relevance. The aim of the study was to assess the effect of minor biologically active substances - carnosine and α-lipoic acid on hepatocyte apoptosis and the cytokine profile in the experimental model of the initial stage of NAFLD. Material and methods. The studies were performed on male Wistar rats with initial body weight of 150±10 g. Animals were divided into 5 groups of 8 rats each. Within 8 weeks, rats of the 1st group (control) received a complete modified diet AIN93M, in which soybean oil was replaced with sunflower oil and lard (1:1). Rats of the experimental groups consumed high-calorie choline-deficient diet (HCCDD), in which fat content was 45%, fructose content - 20% of the energy value of the diet. Rats of the 2nd group were fed HCCDD without any supplements, the 3rd group - with the addition of carnosine (75 mg/kg body weight), the 4th group - with the addition of α-lipoic acid (75 mg/kg body weight), the 5th group - with the addition of carnosine and α-lipoic acid in a total dose of 150 mg/kg body weight. The study of rat hepatocyte apoptosis was performed by flow cytometry. Hepatocytes were stained with annexin V and vital dye 7-aminoactinomycin, followed by detection on an flow cytometer. The content of cytokines and chemokines (IL-1α, IL-10, IL-17А, M-CSF, MIP-1α, MIP-3α, RANTES) in the cytoplasmic fraction of liver tissue was determined by multiplex immunoassay. Results and discussion. On the model of the initial stage of development of NAFLD in male Wistar rats the еnrichment of HCCDD with carnosine and α-lipoic acid had demonstrated a protective effect on hepatocytes with a decrease in apoptosis intensity to the level in control rats. Under the influence of HCCDD, an increase in the content of M-CSF and MIP-1α and a decrease in the levels of MIP-3α and RANTES, stimulating the migration and differentiation of various immunoregulatory populations to the parenchyma at an early stage of the formation of fatty hepatosis, in the cytoplasmic fraction of liver tissue were detected. Moreover, a decrease in the level of proinflammatory cytokines IL-17A and IL-1α and an increase in IL-10 produced mainly by Treg-populations indicate the absence of pronounced inflammatory changes in the liver of male Wistar rats at the initial stages of development of fatty dystrophy. Conclusion. Enrichment of HCCDD with both carnosine and α-lipoic acid in Wistar rats had a protective effect on hepatocytes with a decrease in apoptosis to a level in control rats. The increase in the IL-10/IL-17A ratio indicates the activation of anti-inflammatory mechanisms due to the functional predominance of Treg-cells over Th1/Th17 lymphocytes.

[Effects of polyphenols on activity of glycosyl hydrolases in the cecum of rats fed obesity inducing diets].

The results of experimental studies indicate that the preventive and therapeutic effects of polyphenols in obesity are accompanied by a significant decrease in the severity of dysbiosis caused by the predominance of fats and simple carbohydrates in the diet, especially fructose, and the restoration of the functional state of the microbiota. The aim of the work was to study the effect of quercetin and resveratrol - polyphenols, widely represented in the daily human diet, on the activity of bacterial glycosidases in rats receiving diets high in fructose or fat and fructose. Material and methods. Using spectrophotometric analysis, the activity of ß-galactosidase (Gal), ß-glucosidase (Glu) and ß-glucuronidase (Gluс) was studied in the content of the cecum of Wistar rats receiving a semi-synthetic diet and a 20% solution of fructose instead of drinking water (hfr diet) or a semi-synthetic diet with a high (30%) fat content and a 20% solution of fructose instead of drinking water (hf/hfr diet). Results and discussion. Feeding rats with the hfr diet for 20 weeks led to the suppression of Gal activity by 35, Glu by 46 and Gluс by 31%. With the inclusion of quercetin in the hfr diet at a dose of 34 mg/kg b.w. enzyme activity was restored to the control values and exceeded the level of activity in rats fed hfr ration without quercetin by 60, 100 and 47%, respectively, for Gal, Glu, and Gluс. Feeding rats with the hf/hfr diet for 10 weeks did not have a significant impact on the activity of bacterial enzymes. The inclusion of resveratrol in the hf/hfr diet at a dose of 10 mg/kg b.w. resulted in a decrease in Glu activity by 58 and Gluс by 28%, and an increase in resveratrol dose to 100 mg/kg b.w. caused further suppression of Gal activity by 30, Glu by 76 and Gluc by 64% comparative to the activity in rats on the hf/hfr diet without resveratrol. Conclusion. The obtained data suggest that quercetin restores reduced by hfr diet activity of glycosyl hydrolases of the cecum microflora of rats, most likely due to an increase in the representation of the types of enzyme activity carriers. The suppressive effect of resveratrol on the activity of glycosyl hydrolases of the cecum microflora of rats fed a hf/hfr diet may be the result of its direct action on enzymes and is not associated with the effect on the composition of the intestinal microbiota.

[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.

[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.

[Toxicological evaluation of colloidal nano-sized silver stabilized polyvinylpyrrolidone. III. Enzymological, biochemical markers, state of antioxidant defense system].

Nanosized colloidal silver (NCS) with primary nanoparticles (NPs) size in the range of 10-80 nm in aqueous suspension was administered to rats with initial weight 80±10 gfor the first 30 day intragastrically and for lasting 62 days with the diet consumed in doses of 0.1; 1.0 and 10 mg/kg of body weight b.w) per day based on silver (Ag). The control animals received deionized water and carrier of NPs - aqueous solution of stabilizer polyvinylpyrrolidone. Activity (Vmax) was determined in liver of microsomal mixed function monooxygenase isoforms CYP 1A1, 1A2 and 2B1 against their specific substrates, the activity of liver conjugating enzymes (glutathione-S-transferase and UDP-glucuronosyltransferase) in the microsomal fraction and a cytosol, and the overall and non-sedimentable activities of lysosomal hydrolases. In blood plasma there were evaluated malonic dialdehyde, PUFA diene conjugates, in erythrocytes - the activity of antioxidant enzymes. A set of standard biochemical indicators of blood serum was also determined. The studies revealed changes in a number of molecular markers of toxic action. Among them - the increase in the activity of key enzymes I and II stages of detoxification of xenobiotics, indicating its functional overvoltage; reducing the activity of glutathione peroxidase (GP), the total arylsulfatase A and B, ß-galactosidase (in the absence of changes in their non-sedimentable activity), levels of uric acid, increased alkaline phosphatase activity. These changes occurred mainly at the dose Ag of 10 mg/kg b.w., except for the GP to which the threshold dose was 1 mg/kg b.w. No significant changes in the studied markers in a dose Ag 0,1 mg/kg b.w. were identified. Possible mechanisms of the toxic action of silver NPs are discussed.

[The effect of rutin and hesperidin on the expression of Nrf2- and AhR-regulated genes and CYP3A1 gene in rats intoxicated with carbon tetrachloride].

The purpose of the study was to determine the effects of rutin (R) and hesperidin (Hes), the main representatives of two most studied subclasses of flavonoids - flavonols and flavanones, on the expression of prototypical Nrf2 and AhR-regulated genes and CYP3A1 gene in rats intoxicated with carbon tetrachloride (CCl4). Investigations were carried out on 5 groups of male Wistar rats with the initial body weight (b.w.) 180-200 g (n=40). Rats of the control group and the 1st experimental group received for 14 days the semisynthetic diet, rats of the 2nd experimental group - the same diet plus R (400 mg/kg b.w.), the animals of the 3rd experimental group received the diet with Hes in the same amount, of the 4th experimental group - diet with R (400 mg/kg b.w.) and Hes (400 mg/kg b.w.). Animals of the experimental groups 24 hours before the end of experiment were injected intraperitoneally CCl4 at a dose of 0.5 ml/kg b.w. in olive oil; rats of the control group were injected equal amount of olive oil. For gene expression assessment the mRNA content of NAD(P)H-quinone oxidoreductase (NQO1), heme oxygenase-1 (Hmox1), Nrf2 (Nrf2), AhR (AhR), CYP1A1, CYP1A2, CYP3A1 and ß-actin (Actb) in rat liver was determined by real-time RT-PCR. The results showed that in rats intoxicated with CCl4, enrichment of the diet with R, but not with Hes, led to a significant increase in the expression of genes Hmox1, NQO1 and CYP3A1. Combined intake of R and Hes with the diet led to additivity of their action on the expression of Hmox1 gene and to synergism in the effect on the expression of genes NQO1 and CYP3A1. A moderate increase in the levels of expression of AhR and CYP1A2 genes as compared to their expression in rats treated with CCl4 only, CCl4 and R or CCl4 and Hes has been noted. Thus, for the first time on the model of oxidative stress in rats the data have been obtained showing at the gene expression level a synergism of action of two flavonoids - R and Hes, widely present in the daily human diet.

[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.

[Effects of rutin on protective capacity in rats].

The purpose of the study was to determine effects of rutin dietary administration on the activity of xenobiotic-metabolizing enzymes and antioxidant status. The study has been carried out on 3 groups of male Wistar rats (n = 8 in each), with initial body weight 100-120 g. Animals of the control group (1st group) received standard semi-synthetic diet, the experimental groups--the same diet with rutin in the amount of 40 mg/kg b.w. (2nd group) or 400 mg/kg b.w. (3rd group). The duration of the experiment was 2 weeks. In rat liver the activity of quinone reductase (QR), heme oxygenase-1 (HO-1), paraoxonase-1 (PON-1), glutathione-S-transferase (GST), ethoxyresorufin-O-dealkylase (EROD) activity of CYP1A1, methoxyresorufin-O-dealkylase (MROD) activity of CYP1A2, tes- tosterone 6ß-hydroxylase (6ß-TG) activity of CYP3A, total antioxidant activity (AOA) and malondialdehyde (MDA) content have been investigated. The expression of genes CYP1A1, CYP1A2 and CYP3A has been measured by reverse transcription-polymerase chain reaction (RT-PCR). The stability of lysosome membranes was estimated by the change of unsedimentable activity of lysosomal enzymes--arylsulfatase, ß-galactosidase and ß-glucuronidase. Rutin administration led to dose-dependent increase in the activity of antioxidant enzymes. In rats of the 3rd group received high-rutin diet the activity of QR, HO-1, PON-1 and GST increased by 68, 29, 17 and 22%, respectively, compared to the control (1st group); MDA level and AOA have not changed. Activity of EROD and MROD in liver microsomes of rats treated with rutin at a dose of 40 mg/kg b.w. (2nd group) increased by 33 and 58%, respectively, with a moderate increase in mRNA level of CYP1A1 and CYP1A2. Increasing the dose of rutin up to 400 mg/kg b.w. (3rd group) resulted in the decrease of the degree of EROD and MROD activation by 18 and 15%, respectively, compared to the 2nd group. Rutin had no significant effect on the activity of 6ß-TG and on the expression of CYP3A1 gene. Rutin dietary administration led to dose-dependent reduction of the unsedimentable activity of lysosomal enzymes, indicating the strengthening of the stability of lysosomal membranes. Thus, the obtained results showed that in healthy, intact rats high doses of rutin in the diet moderately but statistically significantly activate enzyme systems responsible for the protective and adaptive capacity of the organism.

[Effects of vitamins deficiency on the cytochrome P450 inducibility in rats].

The purpose of the study was to determine multi-vitamin deficiency effects on the inducibility of main isoforms of cytochrome P450 in the rat liver. The study was carried out on 4 groups of Wistar rats. Rats of the 1st and 3rd group received semi-synthetic diets containing adequate (100% of recommended vitamin level) level of vitamins, the 2nd and 4th--the semi-synthetic diet containing vitamins in the amount of 20% from adequate level. The duration of the experiment was 4 weeks. During the last week indole-3-carbinol (I-3-C) in dose of 20 mg/kg body weight was added to the diet of the 3rd and 4th group of rats. Vitamin E content in liver and blood serum declined by 59 and 34%, respectively in rats which were fed vitamin-deficient diet (2nd group); vitamin A level decreased by 5 times in the liver, but was not changed in blood serum. Multi-vitamin deficiency in the diet led to the increase in the liver ethoxyresorufin O-dealkylase (EROD) activity of CYP1A1, methoxyresorufin O-dealkylase (MROD) activity of CYP1A2 and testosteron 6beta-hydroxylase (6beta-TG) activity of CYP3A by 11, 80 and 53%, respectively, and gene expression of CYP1A1, CYP1A2, CYP3A and AhR by 8,5; 1,6; 2,4 and 3,6 fold. In rats fed diet with adequate levels of vitamins (3rd group) I-3-C increased activity of EROD and MROD by 4,4 and 5,5 fold, and the expression of CYP1A1, CYP1A2 and AhR genes by 148; 3 and 3,5 fold compared to the parameters of the 1st group (without I-3-C). Multi-vitamin deficiency increased I-3-C-related induction of EROD activity and expression of CYP1A1 and CYP1A2 genes, but decreased I-3-C-related induction of the MROD activity. Thus, 5-fold reducing of vitamin content in rat diet lead to significant changes in activity and inducibility of cytochrome P450 of CYP1A and 3A family, which play a key role in the detoxification and metabolism of drugs.

Effect of polyunsaturated fatty acids ω-3 on the induction of activity and expression of CYP1A1 and CYP1A2 genes in the liver of rats under the influence of indole-3-carbinol.

Supplementation of the ration with eicosapentaenoic and docosahexaenoic ω-3 polyunsaturated fatty acids (PUFA) in doses of 0.3 and 1 g/kg body weight for 4 weeks had no effect on ethoxyresorufin O-dealkylase (EROD) activity and expression of the CYP1A1 gene in male Wistar rats, but caused a dose-dependent increase in methoxyresorufin O-dealkylase (MROD) activity of CYP1A2 (by 28 and 73%, respectively) without significant changes in CYP1A2 mRNA expression. ω-3 PUFA had no effect on the indole-3-carbinol-induced (20 mg/kg body weight over the last 7 days of the experiment) EROD activity and expression of CYP1A1 mRNA. The indole-3-carbinol-induced MROD activity was shown to increase by 6.2 times in rats not receiving ω-3 PUFA and only by 3.9 and 2.7 times in animals receiving ω-3 PUFA. The indole-3-carbinol-induced expression of CYP1A2 mRNA slightly increased in animals receiving ω-3 PUFA. Our results suggest that the effect of ω-3 PUFA on the induced and basal activity of CYP1A2 is not related to modulation of CYP1A2 gene expression.

[Toxicological assessment of nanostructured silica. II. Enzymatic, biochemical indices, state of antioxidative defence].

Nanostructured silica (SiO2) "Aerosil" with the size of the primary nanoparticles (NPs) of 5-30 nm, in the form of ultrasound treated water suspension was administered to rats of 80 ± 4 g initial body weight for the first 30 days by intragastric gavage and then for 62 days with diets consumed in doses of 0.1; 1.0; 10 and 100 mg/kg body weight per day. The control group received vehicle of nanomaterial (NM)--deionized water. There were measured in liver of ani- mals the content of total cytochromes P450 and b5 in the microsomal fraction of liver, activity (Vmax) of microsomal monooxygenases with the mixed func- tion of isoforms CYP1A1, 1A2 and 2B1 on their specific substrates, the activity of conjugating liver enzymes glutathione-S-transferase and UDP-glucuronosyl-transferase in microsomal fraction and cytosol, the total and non sedimentable activity of lysosomal hydrolases (ß-glucuronidase, ß-galactozydase, arylsulphatase A, B). The content of PUFA's diene conjugates and TBA-reactive substances in the blood plasma and the activity of antioxidative enzymes (glutathionperoxidase, superoxidedismutase, glutathionreductase, katalase) in erytrocytes were estimated. A set of standard biochemical parameters of blood serum was also examined (total protein, albumin, glucose, creatinine, urea, uric acid, activities of hepatic transaminases). The studies revealed changes of a number of molecu lar markers that could be interpreted as unfavorable. These include isoforms of CYP2B1 activity decrease at a dose HM 1-10 mg/kg of body weight, decrease in the serum content of total protein, albumin and glucose levels in a dose range of 0.1-10 mg/kg. These changes were absent at the maximum dose of NM, which did not allow to clearly establish the dose-response. The remaining studied fig ures resided in the normal range or experienced changes that could not be interpreted as toxic.

[Effects of rutin on the activity of antioxidant enzymes and xenobiotic-metabolizing enzymes in liver of rats fed diets with different level of fat].

The study has been carried out on 6 groups of male Wistar rats, which received semi-synthetic diets within 28 days. Rats of 1st and 4th group received fat-free diet, 2nid.and 5th - diet containing standard amount of fat (10% by weight, 26% by caloric content; lard/sunflower oil - 1/1); 3rd and 6th group - a high-fat diet (30% by weight, 56% by caloric content). During the last 14 days of the experiment rats received rutin in the dose of 40 mg/kg b.w. AOA, MDA level and the activity of paraoxonase I have been evaluated in blood serum. In rat liver along with the parameters of the antioxidant status (MDA level, activity of paraoxonase 1, quinone reductase, heme oxygenase-1) the activity of xenobiotic-metabolizing enzymes (XME) (CYP1A1, CYP1A2, CYP3A1, CYP2B1, UDP-glucuronosyl transferase and glutathione transferase) and the activity of lysosomal enzymes (arylsulfatase A and B, ß-galactosidase and ß-glucuronidase) have been investigated. Elevation of the activity of antioxidant enzymes and XME in liver with the increase of diet fat content has been-noted. Rutin admihistration had no effect onparamete6rs of antioxidant status and decreased unsedimentable activity of lysosomal enzymes that did not depend on fat content in the diet. Rutin receiving increased the activity of all studied XME in rats fed standard diet, but practically did not effect on their activity in rats fed by fat-free and high-fat diets. Thus, rutin in pharmacological dose has no effect on the activity of antioxidant enzymes that doesn't depend on the level of fat in the diet, while the decrease or increase of diet fat content modulates (weakens) the influence of rutin on the XME activity.

[Effects of omega-3 polyunsaturated fatty acids on antioxidant capacity in rats].

Dietary administration of omega-3 polyunsaturated fatty acids (EPA + DHA, 1,2:1) at dose 0.3 or 1 g/kg bw during 4 weeks led to minor (by 14% and 17%, p<0.05) decrease of serum antioxidant capacity and serum level of vitamin E (by 30% and 31%, p<0.05) and the activity of paraoxonase-1 (by 14% at 0.3 g/kg bw, p<0.05). The activity of antioxidant enzymes in liver increased in a dose-dependent manner. At higher dose of omega-3 polyunsaturated fatty acids a 45% increase in the activity of paraoxonase-1 (p<0.05), 21% -heme oxygenase-1 (p>0.05), 68% - quinone reductase (p<0.05), 19% - glutathione S-transferase (p<0.05) compared to the control group was found. The direct relationship between activities of enzymes and increase of MDA level in liver (by 47 and 107%, p

[Effect of dietary fat on vitamin status of rats].

The influence of low (1%) and high (31%) diet fat content (sunflower-seed oil and lard 1:1 at a ratio of 1:1) on vitamin A, E, B1 and B2 status of growing Wistar rats (8 rats per group) with initial body weight 80-100 g has been investigated. The semi-synthetic diet contained vitamin mixture in doses covering the physiological requirement of these animals. The increase of fat content (31%) in the diet due to the presence of vitamin E in sunflower-seed oil automatically lead to 1,7-fold increase consumption of this vitamin compared to the control group. Diet fat content did not affect the level of vitamins B1 and B2 in rat liver. Excessive intake of fat and vitamin E for 6 weeks did not influence on the content of blood plasma vitamin E and rat liver vitamin A occurs at the same time, while significant 1,9 fold elevation of liver vitamin E level and 26 per cent increase of blood plasma vitamin A concentration. The almost complete exclusion of fat from the diet had no effect on blood plasma level of alpha-tocopherol and retinol, but resulted in a significant decrease of vitamins A and E content in rat liver by 40 per cent, indicating a deterioration of sufficiency with these fat-soluble vitamins. The analysis of the results obtained in this investigation and literature data have suggested that under excessive as well as under decreased consumption of fat there is a risk of the development of polyhypovitaminosis. Vitamin complex supplementation is required to prevent a possible worsening of vitamin status under diets with modified fatty component.