ANTIOXIDANT PROTECTION OF ADEMETIONINE IN THE TOXIC EFFECT OF ANTI-TUBERCULOSIS DRUGS

The article contains the results of an experimental toxicological study of the use of ademetionine as an antioxidant defense of the rat body when using anti-tuberculosis drugs

Flight and dietary antioxidants influence antioxidant expression and activity in a migratory bird

Ecologically-relevant factors such as exercise and diet quality can directly influence how physiological systems work including those involved in maintaining oxidative balance; however, to our knowledge, no studies to date have focused on how such factors directly affect expression of key components of the endogenous antioxidant system (i.e., transcription factors, select antioxidant genes, and corresponding antioxidant enzymes) in several metabolically active tissues of a migratory songbird. We conducted a 3-factor experiment that tested the following hypotheses: (H1) Daily flying over several weeks increases the expression of transcription factors NRF2 and PPARs as well as endogenous antioxidant genes (i.e., CAT, SOD1, SOD2, GPX1, GPX4), and upregulates endogenous antioxidant enzyme activities (i.e., CAT, SOD, GPx). (H2) Songbirds fed diets composed of more 18:2n-6 PUFA are more susceptible to oxidative damage and thus upregulate their endogenous antioxidant system compared to when fed diets with less PUFA. (H3) Songbirds fed dietary anthocyanins gain additional antioxidant protection and thus upregulate their endogenous antioxidant system less compared to songbirds not fed anthocyanins. Flight training increased the expression of 3 of the 6 antioxidant genes and transcription factors measured in the liver, consistent with H1, but for only one gene (SOD2) in the pectoralis. Dietary fat quality had no effect on antioxidant pathways (H2) whereas dietary anthocyanins increased the expression of select antioxidant enzymes in the pectoralis, but not in the liver (H3). These tissue-specific differences in response to flying and dietary antioxidants are likely explained by functional differences between tissues as well as fundamental differences in their turnover rates. The consumption of dietary antioxidants along with regular flying enables birds during migration to stimulate the expression of genes involved in antioxidant protection likely through increasing the transcriptional activity of NRF2 and PPARs, and thereby demonstrates for the first time that these relevant ecological factors affect the regulation of key antioxidant pathways in wild birds. What remains to be demonstrated is how the extent of these ecological factors (i.e., intensity or duration of flight, amounts of dietary antioxidants) influences the regulation of these antioxidant pathways and thus oxidative balance.

Evaluation of the Safety and Toxicity of the Original Copper Nanocomposite Based on Poly-N-vinylimidazole

A new original copper nanocomposite based on poly-N-vinylimidazole was synthesized and characterized by a complex of modern physicochemical and biological methods. The low cytotoxicity of the copper nanocomposite in relation to the cultured hepatocyte cells was found. The possibility to involve the copper from the nanocomposite in the functioning of the copper-dependent enzyme systems was evaluated during the incubation of the hepatocyte culture with this nanocomposite introduced to the nutrient medium. The synthesized new water-soluble copper-containing nanocomposite is promising for biotechnological and biomedical research as a new non-toxic hydrophilic preparation that is allowed to regulate the work of key enzymes involved in energy metabolism and antioxidant protection as well as potentially serving as an additional source of copper.

Prognostic value of endotoxicosis criteria in the diagnosis of acute renal injury

In order to find informative statically significant laboratory criteria for endotoxicosis in the diagnosis of acute renal injury, a clinical and biochemical study of 40 patients with acute renal injury developed against the background of renal urological and extrarenal surgical pathology was conducted. The results of the study demonstrate pronounced changes in the mechanisms of antioxidant protection that develop in patients with acute renal injury. Deviations from the initial level of the studied criteria are interrelated with many links of pathogenesis, where one of the central links is ischemia of the renal parenchyma. The progression of endogenous intoxication, taking into account the data obtained, confirmed by a decrease in prooxidant protection contributes to the progression of intrarenal changes, aggravating functional changes in renal and extrarenal injuries. Key words: significance of endotoxicosis criteria, acute renal injury, endotoxicosis, serum creatinine, glomerular filtration rate.

EFFECT OF OLIGOSACCHARIDES ON ENZYMES OF CARBOHYDRATE METABOLISM AND ANTIOXIDANT PROTECTION IN IN VITRO TREATED ERYTHROCYTES UNDER CONDITIONS OF HYPERGLYCEMIA

Introduction: The purpose of this experiment is to examine the effect of different oligosaccharides with proven prebiotic effects on enzymes of carbohydrate metabolism and the antioxidant protection of erythrocytes in vitro under conditions of hyperglycemia. Materials and methods: This experiment included 10 healthy men (27±3 years of age). The isolated erythrocytes were treated with 1% and 5% solutions of the following oligosaccharides: lactulose, inulin, galactooligosaccharide and fructooligosaccharide in the presence of 5mM, 50mM and 100mM glucose. After incubation, for 2 hours at 37 °C, the erythrocytes were lysed, and the supernatant was used for analyses of lactate dehydrogenase, hexokinase and glutathione reductase. FRAP (Ferric reducing antioxidant power) method was used for determining the total antioxidant activity of erythrocytes. Results: Lactate dehydrogenase was decreased in the presence of 5% lactulose in groups with 50mM and 100 mM Glc. An increase in the activity of glutathione reductase under severe hyperglycemia (100mM glucose) was observed after treatment with: 1% lactulose, 1% inulin, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides (p<0.005). A significant difference in the enzymatic activity of hexokinase was found in all groups (p<0.05) and of glutathione reductase only in the control group as well as in the groups treated with 1% lactulose, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides Conclusions: Galactooligosaccharides 1% and fructooligosaccharides 1% and 5% cause a statistically significant increase of the enzymatic activities of hexokinase and glutathione reductase in in vitro hyperglycemia induced by 100 mM glucose, as well as an increase in FRAP.

Some indicators of free radical oxidation and antioxidant protection in the erythrocytes of former athletes

Objective: to study the main indicators of free radical oxidation and antioxidant protection in the erythrocytes of former athletes, depending on the period of termination of sports.Materials and methods: 24 former male athletes aged 19–29 years were examined, who were divided into 2 groups of 12 people each (1st group — former athletes who stopped training for up to 2 years; 2nd — over 2 years). The control group consisted of 15 practically healthy untrained student volunteers of the same age. In erythrocytes, spectrophotometrically (spectrophotometer Shimadzu 1240, Japan), the activity of antioxidant enzymes was determined: superoxide dismutase (SOD) (K.F. 1.15.1.1) — by inhibiting the reduction of nitro blue tetrazolium by superoxide anion radical at λ = 540 nm, after preliminary processing of erythrocytes by the method of Dubinina E.E. and others [8]; catalase (K.F. 1.11.1.6) — according to the rate of utilization of hydrogen peroxide at λ = 260 nm; glutathione peroxidase (HP) (KF 1.11.1.9) — by the change in the content of reduced glutathione in samples before and after incubation of the substrate with dithiobis-nitrobenzoic acid at λ = 412 nm; glutathione reductase (GR) (K.F. 1.6.4.2) — according to the catalytic NADPH ∙ H+-dependent transformation of the oxidized form of glutathione into the reduced form, the intensity of which was estimated by the rate of decrease in the extinction of samples at λ = 340 nm, at which the NADPH H+ solution has a maximum light absorption (Warburg test).Results: the direction of the shifts in the state of the oxidative balance was established depending on the period of detraining. A significantly lower value of the total antioxidant activity was revealed in the former athletes of the 1st group. This phenomenon is probably associated with a decrease in the efficiency of the enzymatic link of the antioxidant defense in the absence of regular physical exertion, and, as a consequence, an increased consumption of non-enzymatic antioxidants. It was found that the early post-sports period is characterized by significantly lower, in comparison with the control group, the values of the activity of the first-order enzymes (superoxide dismutase) against the background of the increased activity of the second-order enzymes (catalase).Conclusions: the obtained data can be recommended for monitoring the state of athletes who stopped playing sports and taken into account when prescribing rehabilitation measures for the corresponding contingent.

Biochemical criteria for the development mechanisms of various reproduction disorders in dairy cows

Ventsova I, Safonov V. 2021. Biochemical criteria for the development mechanisms of various reproduction disorders in dairy cows. Biodiversitas 22: 4997-5002. The article presents the evaluation of peroxide, antioxidant, and hormonal conditions of high-producing red-and-white dairy cows in the physiological and pathological course of pregnancy and the postpartum period. The blood concentration of malonic dialdehyde, stable nitric oxide metabolites, S-nitrosothiols, vitamins E and C, carotin, gonadal, corticosteroid, and thyroid hormones, as well as activity of GPx, GR, SOD, catalase, and ceruloplasmin, were estimated to define major disorder-provoking factors. Analysis of the data shows that ketosis-gestosis syndrome during pregnancy, postpartum metritis, and gonadal dysfunction occur mainly because of oxidative stress in the context of unbalanced peroxide responses and antioxidant protection. Levels of malonic dialdehyde compared to healthy animals increased by 42.3%, 75%, 56.6%, respectively, as also enzyme activities of GR by 26%, 68.1%, 30.1% and catalase by 17.3%, 45.1%, and 23.9%, correspondingly. The endocrine status indicators in the animals with ketosis-gestosis syndrome changed as follows: progesterone levels were 29.5% lower in cows, 17?-estradiol and cortisol were 20.8% and 14.7% lower, respectively. In animals with inflammatory uterine diseases and depressing reproductive glands, progesterone level was 2 and 3 times lower than in healthy animals, the content of cortisol was 17.6% and 25.1% lower, and testosterone decreased by 21.4% and 75.1%, respectively.

The Efficacy of a Peptide Product from the Pituitary Gland of Rangifer tarandus as an Antioxidant Agent Under the Combined Effects of Light Desynchronosis and Depriming Toxicant

The possibility of using methods for determining the oxidative status of an organism (enzymatic and non-enzymatic links of the cellular antioxidant system) to assess the antioxidant properties of peptides of the pituitary gland of the reindeer (Rangifer tarandus) were investigated in an experimental study conducted with a combined effect of factors of different nature on rats: a physical factor — prolonged light desynchronosis (different light modes) and a chemical factor - acute severe poisoning with depriving toxicant (sodium thiopental, LD50). The pharmacological correction of the oxidative status of cells in the animals of the experimental subgroups was carried out with the peptide product of the pituitary gland, intranasally injecting the surviving rats with the bioproduct at a dose of 100 µg/kg, once in the first half of the objective day for 14 days after poisoning with sodium thiopental. The surviving animals of the control groups were similarly injected with saline. The effectiveness of the correction of the disruptions of the cellular oxidative status with the peptide product of the pituitary gland was tested 30 days after the onset of the combined effect of stress factors on rats. It was found that the use of this bioactive peptide product in experimental animals exposed to different light modes and a chemical factor contributed to a decrease in the initially increased indicators of lipid peroxidation in rat erythrocytes and an increase in the initially reduced indicators of the enzymatic link of antioxidant protection. The activity of superoxide dismutase, glutathione peroxidase, glutathione transferase, as well as glucose-6-phosphate dehydrogenase increased after pharmacological correction. The concentration of reduced glutathione also increased in erythrocytes. The maximum changes were observed in the experimental subgroup of rats exposed to the combined effects of constant illumination and depriming toxicant. It was also found that the revealed positive changes in the indicators of the enzymatic link of antioxidant protection in animals of the experimental subgroups are associated with the maintenance of a sufficient concentration of reduced glutathione in red blood cells, which contributed to the maintenance of the cellular redox balance, when the conditions of the external lighting regime are violated.