INTENSITY OF FREE RADICAL PROCESSES IN THE POSTNUCLEAR FRACTION OF RAT KIDNEYS UNDER INFLUENCE OF LASER IRRADIATION AND ω-3 POLYUNSATURATED FATTY ACIDS

Introduction. The effect of laser irradiation on the body can lead to local tissue damage, which will be accompanied by changes in biochemical processes that occur in the kidneys. The direction of these changes is completely unclear, so the study of free radical oxidation of lipids and proteins as the main markers of oxidative stress in the body and their correction by ω-3 polyunsaturated fatty acids (PUFA) remains relevant. Aim. To evaluate the intensity of lipid peroxidation and oxidative modification of proteins in the postnuclear fraction of rat kidneys under the action of laser irradiation and additional administration of ω-3 PUFA. Methods. The studies used white outbred rats, which were irradiated daily for 4 minutes with a laser diode with a wavelength of 650 nm, power of 50 mW in the abdominal cavity at a distance of 10 cm from the skin surface. The state of lipid peroxidation (LPO) was determined by the level of primary, secondary and final products. The intensity of oxidative modification of proteins (OMP) was evaluated by the level of carbonyl derivatives and protein SH-groups. To correct the prooxidant state, the animals were additionally injected with ω-3 PUFA. Results. Low-intensity laser irradiation has a destructive effect on the cell membranes of the kidneys, which is expressed by an increase in primary, secondary and final products of LPO in phospholipid extracts and an increase in the intensity of OMP. The introduction of ω-3 PUFAs reduces free radical processes in the kidneys of irradiated rats, but this effect depends on the scheme of their introduction. ω-3 PUFAs do not show antioxidant effect under the conditions of their introduction after laser irradiation. Daily administration of ω-3 PUFA two hours before irradiation shows a slight antioxidant effect only in the initial stages of irradiation. Preliminary seven-day administration of ω-3 PUFA before laser irradiation is the most effective, as it helps to reduce free radical processes. Conclusion. It is established that ω-3 PUFAs are able to have a corrective effect on the action of low-intensity laser irradiation, which depends on the scheme of their introduction. The highest antioxidant effect is observed in groups of animals to which ω-3 PUFA was previously administered before the action of laser irradiation.

Changes in biomarkers of endothelial function in the blood after intracerebral hemorrhage in rats with type 2 diabetes mellitus

Clinical evidence suggests that type 2 diabetes mellitus can increase the risk of intracerebral hemorrhage and provocation of neurodegeneration. This study was aimed at evaluating biomarkers of glycemic control, lipid profile, oxidative modification of proteins, as well as the functional state of endothelium in Wistar rats with type 2 diabetes mellitus complicated by intracerebral hemorrhage. Experimental type 2 diabetes mellitus was induced by intraperitoneal injection of streptozotocin (65 mg/kg) and nicotinamide (230 mg/kg). The intracerebral hemorrhage was induced by microinjection of sterile saline containing 0.2 IU bacterial collagenase into the striatum. Assessed biomarkers included the area under glycemic curve, glycated hemoglobin, total cholesterol, triglyceride, high-density lipoprotein, advanced glycation end products, markers of oxidative modification of proteins – aldehyde- and ketonephenylhydrazones, and markers of endothelial dysfunction – homocysteine, endothelin-1, von Willebrand factor and asymmetric dimethylarginine in blood serum. Both rats with type 2 diabetes mellitus and rats with intracerebral hemorrhage and diabetes had a significant elevated glycemic control as compared to intact animals. But combined pathology was additionally characterized by an impairment of lipid profile (increased triglyceride level and decreased as total cholesterol and high-density lipoprotein) resulting in a rise in the atherogenic index of plasma. A significant increase in the content of the markers of oxidative modification of proteins was observed in both experimental groups. But the rats with intracerebral hemorrhage and diabetes only had higher levels of advanced glycation end products in comparison with intact animals. The highest levels of endothelin-1, as a biomarker of endothelial dysfunction, were observed in animals with intracerebral hemorrhage and diabetes. Homocysteine and von Willebrand factor were elevated in rats with type 2 diabetes mellitus, while acute intracerebral hemorrhage did not potentiate the further growth in its levels. Such effect was not accompanied by a marked increase of asymmetric dimethylarginine level in blood serum, although there was a clear trend. In conclusion, the development of intracerebral hemorrhage in rats with type 2 diabetes mellitus can intensify the manifestations of oxidative stress, worsen lipid profile, and aggravate endothelial dysfunction. In this case, the pathological process may have the character of a “vicious circle”.

The study of oxidative stress indicators in rats with a simulated acute hepatitis and correction with a thick extract from reishi mushrooms

The aim. To study the effect of a dry extract from reishi mushrooms on the activity of lipoperoxidation and oxidative modification of proteins under the conditions of a simulated paracetamol hepatitis in rats. Materials and methods. The study was performed on white male rats. The animals were divided into 10 groups, each included 6 animals. Acute hepatitis was simulated by the intragastric administration of paracetamol in the dose of 1250 mg/kg once per day (for 2 days). Correction of the pathology induced was performed with a dry extract of reishi mushrooms in the dose of 100 mg/kg of the body weight. The reference drug “Silybor” was administered in the dose of 20 mg/kg of the animal body weight. On Day 3, 7 and 10 from the beginning of the lesion, rats were euthanized using sodium barbamyl. The liver homogenate and blood serum were used for the studies. The activity of free radical oxidation processes under the conditions of acute toxic hepatitis and after the introduction of corrective factors was assessed by superoxide dismutase, catalase activity, the content of TBA-AP and OMP products. Results and discussion. The development of acute paracetamol hepatitis in rats and damage of hepatocyte membranes are indicated by an increase in the content of TBA-active products, products of oxidative modification of neutral and basic proteins in the serum and liver of animals. Simultaneously, a decrease in the activity of catalase and superoxide dismutase was observed. After correction of the pathology induced with a dry extract of reishi mushrooms a significant increase in the activity of antioxidant enzymes, a decrease in the content of lipid peroxidation products and oxidative modification of proteins in the serum and liver of the affected animals were observed. Conclusions. It has been experimentally proven that the use of dry extract of Reishi mushrooms in paracetamol hepatitis in rats caused a significant decrease in catalase and superoxide dismutase activity, a decrease in TBA-AP, neutral and basic 2,4-DNPH in the serum and liver of animals. The results of the research indicate an effective impact of reishi mushrooms dry extract on the normalization of lipoperoxidation, oxidative modification of proteins and antioxidant protection

Histochemical Study of the Processes of Protein Oxidative Modification and Limited Proteolysis in the Endothelium of Myometrial Vessels in the Projection of the Utero-Placental Bed during Iron-Deficiency Anemia in Pregnancy

Utero-placental bed is the cumulation of gestationally altered endometrium at the place of ovum attachment to the uterine wall. As far as the protein oxidative modification and limited proteolysis in iron deficiency anemia are due to the fact that in conditions of hypoxia, free radical processes in the blood and tissues are enhanced, and iron deficiency is additionally able to cause hemodynamic disorders because of endothelial dysfunction in the vessels of the utero-placental area. The purpose of the study was to establish histochemical features of protein oxidative modification and limited proteolysis in the endotheliocytes of myometrial vessels in the projection of the utero-placental area depending on the degree of iron deficiency anemia in pregnant women. Materials and methods. By histochemical methods of Mikel Calvo, using reactions with bromophenol blue on "acidic" and "basic" proteins, and the method of A. Yasumа and T. Ichikawa, ninhydrin-Schiff reaction to free amino groups of proteins to assess the degree of limited proteolysis, in combination with computer microspectrophotometry and microdensitometry, quantitative characteristics of oxidative modification of proteins and limited proteolysis in endotheliocytes of myometrial segments of the utero-placental vessels in iron deficiency anemia of pregnant women were established. 74 biopsies of the observed uterine-placental area in physiological pregnancy and gestation based on iron deficiency anemia of I, II and III degrees of severity were investigated. Results and discussion. In physiological pregnancy, the intensity of oxidative modification of proteins and limited proteolysis is the lowest in endotheliocytes of myometrial segments of the spiral arteries and the highest one is in the endothelium of the vessels of the microcirculatory tract of the utero-placental area. In gestations based on iron deficiency anemia, intensification of proteins oxidative modification and limited proteolysis in the endothelium of all types of myometrial vessels of the projection of the utero-placental bed correlates with the severity of anemia. Iron deficiency anemia greatly affects the modification of proteins in the endothelial cells mostly of myometrial segments of spiral arteries of the placental bed. Conclusion. Intensification of protein oxidative modification and limited proteolysis in endotheliocytes of all type vessels of myometrium of the uterine-placental area formed by iron deficiency can be considered as a significant factor of endothelial dysfunction and a predictor of hemodynamic disorders of the placental bed

Correction of redox metabolism and the relationship of markers of systemic chronic inflammation with a measure of overall survival in cancer patients with multiorgan resections

Background. According to the literature, multiorgan resections are carried out with the most radical removal of healthy tissue. Therefore, there is a need for the most favorable preparation of the patient with perioperative therapy to reduce further complications with obtaining improved clinical and pathological prognostic indicators to increase the overall survival. Purpose: correction of redox metabolism based on the data of the oxidative modification of proteins, degree of their catabolic reaction, and data on the enzymatic state and lipid peroxidation in cancer patients with multiorgan resections on the gastrointestinal tract under conditions of perioperative intensive care. Materials and methods. The study involved 117 cancer patients aged 67.6 ± 3.7 years with locally advanced tumor processes of the gastrointestinal tract. Studies have been conducted on the enzymatic state, lipid peroxidation and oxidative modification of proteins, both in terms of the degree of fragmentation of their products in spontaneous and iron-induced reactions, and the level of medium-weight protein molecules. Serum levels of circulating tumor necrosis factor alpha, interleukin-6 and -8 were determined. Survival analysis was performed using the Kaplan-Meier method. Results. The study of patients has shown an improvement in the indicators of oxidative modification of proteins and lipid peroxidation. Survival in cancer patients with multiorgan resections demonstrated dependence on the levels of tumor necrosis factor alpha, interleukin-6 and -8 in the blood serum. Conclusions. Conducting perioperative intensive care makes it possible to reliably restore indicators of the enzymatic state, lipid peroxidation and oxidative protein modification products (on the fourth day and second week, p < 0.05). This gives us grounds for recommending the determination of these parameters in the group of cancer patients and the implementation of metabolic intensive care. In the group of L-ornithine L-aspartate and quercetin combination with povidone, the lowest indicators of systemic chronic inflammation and the best overall survival were found.

LIPID PEROXIDATION AND OXIDATIVE MODIFICATION OF PROTEINS IN THE PATHOGENESIS OF TICK-BORNE ENCEPHALITIS AND IXODIC TICK-BORNE BORRELIOSIS

Ixodic tick-borne borreliosis occupies a leading place among natural focal vector-borne infections in the Chelyabinsk region, and tick-borne encephalitis is less common. In the pathogenesis of the vast majority of diseases known to date, non-specific pathochemical processes are of the greatest importance. One of the most significant metabolic processes of this kind is free radical oxidation. Objective: to study the etiological structure and clinical features of tick-borne encephalitis and ixodic tick-borne borreliosis in comparison with the characteristics of the manifestations of oxidative stress in various clinical forms of tick-borne infections in the endemic region (for example, the Chelyabinsk region). Methods: Clinical studies were conducted on the basis of the Department of Infectious Diseases of the city Center of Neuroinfections, the 1st and 4th infectious departments of the MAUZ OZP GKB No. 8 in Chelyabinsk. The diagnosis of CE, ICB was established after a comprehensive clinical and laboratory study. The content of carbonyl products of oxidative modification of proteins was evaluated by their reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH). In determining the content of primary and secondary products of lipid peroxidation, a method based on the phenomenon of rearrangement of double bonds into diene conjugates was used. Conclusions: The leading place among natural-focal vector-borne infections in the Chelyabinsk region is occupied by ICB, and CE is less common. The revealed changes in the study of oxidative stress in patients with CE and ICB not only indicate the prospects for developing new approaches to the pathogenetic therapy of tick-borne infections, involving the use of antioxidants in complex therapy, but also suggest a greater effectiveness of direct-acting lipophilic antioxidants that limit diene conjugation, and thereby prevent the accumulation of secondary cytotoxic products of lipid peroxidation.

Antioxidant activity of heterocyclic amino containing derivatives of naphthoquinone and their compositions with surface-active rhamnolipids

Composite preparations based on heterocyclic amine-containing naphthoquinone derivatives and surfactant rhamnolipids were obtained. The intensity of the processes of lipid peroxidation (LPO), oxidative modification of proteins (OMB) and radical-absorbing activity against 1,1-diphenyl-2-picrylhydrazyl (DFPG) was studied. Compounds exhibiting high antioxidant activity against LPO and OMB processes were identified, namely: 2-[(6-(4-fluorophenyl-5-oxo-2,5-dihydro-1,2,4-triazin-3-yl) phenyl)amino]naphthalene-1,4-dione 1d and its composite preparation with rhamnolipid 1d + RL. It was found that all synthesized compounds show antioxidant activity in LPO processes.

The level of carbonylation of plasma proteins and peripheral blood leukocytes in patients with different duration of Alzheimer’s disease

The course of Alzheimer’s disease is associated with an increase in oxidative stress associated with an increase in the production of reactive oxygen species against the background of neurodegenerative inflammation, and a simultaneous depletion of the antioxidant defense capabilities of brain cells. The result is the oxidative modification of macromolecules: proteins, lipids, nucleic acids. Protein carbonylation products accumulate not only in neurons, and in direct correlation with the degree of increase in amyloidosis and neurodegeneration, but also in extra-neuronal tissues, including leukocytes. In the course of this study, the levels of spontaneous and induced oxidative modification of proteins were determined in the blood plasma and fractionated leukocytes of peripheral blood of patients with different durations of Alzheimer’s disease, and the value of the reserve-adaptive potential was assessed as markers of the severity of oxidative stress. It has been established that the course of Alzheimer’s disease has a greater effect on the accumulation of carbonyl derivatives in blood plasma. In patients with a disease duration of 5–10 years, the total level of aldehyde and ketone derivatives of modified plasma proteins exceeds the same indicator in subgroups with a shorter duration of the disease. This tendency is less typical for mononuclear leukocytes. The level of induced oxidative modification of proteins increases to a greater extent in blood plasma than in fractionated leukocytes. This indicates the depletion of the reserve-adaptive potential of plasma antioxidant capabilities, which is more pronounced in patients with a long course of Alzheimer’s disease. For polymorphonuclear leukocytes, such a pattern was not revealed, which is probably associated with a short cell life. In mononuclear leukocytes, as well as in plasma, there is a tendency to depletion of the reserve-adaptive potential, but to a lesser extent.