Intensity Of Free Radical Processes Research Articles

CHANGES IN THE METABOLISM OF NATIVE AND DECONSERVED BULL SPERMATOZOA UNDER THE ACTION OF MOLECULAR HYDROGEN

Background. The process of storing sperm in a deeply frozen state causes structural and functional disorders of spermatozoa, which reduces their fertilizing ability. The main mechanism of the negative effect of cryopreservation on spermatozoa is the development of oxidative stress. Molecular hydrogen has some advantages as a potential antioxidant molecule - it is a selective effect on certain reactive oxygen species, the ability to overcome cell membranes, the absence of toxic effects. Purpose. To study the effect of molecular hydrogen on the functional status of native and deconserved sperm cells of breeding bulls. Materials and methods. The object of the study was the ejaculates of bulls before cryopreservation and after defrosting. The native sperm diluted with the "BioXcell" diluent, the native sperm diluted with the "BioXcell" diluent enriched with molecular hydrogen, the sperm after deep freezing and the sperm after deep freezing pretreated with molecular hydrogen were studied. The intensity of free radical processes and the activity of antioxidant enzymes were determined in spermatozoa. Results. After cryopreservation of sperm, the processes of lipid peroxidation in spermatozoa are significantly activated. The content of malondialdehyde, diene and triene conjugates increases. The use of molecular hydrogen to correct the quality of sperm production after cryopreservation gave positive results. A decrease in the concentration of primary and intermediate products of lipid peroxidation was noted. The activity of superoxide dismutase and catalase in spermatozoa significantly increases. Conclusion. Molecular hydrogen has the potential as a new and effective antioxidant, the widespread use of which is possible for veterinary purposes. Sponsorship information. The study was funded by the Russian Science Foundation grant No. 23-26-00205.

С60 fullerene protective effect against the rat muscle soleus trauma

Muscle trauma is one of the most common body injuries. Severe consequences of muscle trauma are ischemic injuries of the extremities. It is known that the intensification of free radical processes takes place in almost most acute diseases and conditions, including muscle trauma. C60 fullerene (C60) with powerful antioxidant properties can be considered a potential nanoagent for developing an effective therapy for skeletal muscle trauma. Here the water-soluble C60 was prepared and its structural organization has been studied by the atomic force microscopy and dynamic light scattering techniques. The selective biomechanical parameters of muscle soleus contraction and biochemical indicators of blood in rats were evaluated after intramuscular injection of C60 1 h before the muscle trauma initiation. Analysis of the force muscle response after C60 injection (1 mg kg−1 dose) showed its protective effect against ischemia and mechanical injury at the level of 30 ± 2 % and 17 ± 1 %, accordingly, relative to the pathology group. Analysis of biomechanical parameters that are responsible for correcting precise positioning confirmed the effectiveness of C60 at a level of more than 50 ± 3 % relative to the pathology group. Moreover, a decrease in the biochemical indicators of blood by about 33 ± 2 % and 10 ± 1 % in ischemia and mechanical injury, correspondingly, relative to the pathology group occurs. The results obtained demonstrate the ability of C60 to correct the functional activity of damaged skeletal muscle.

Adaptogenic correction of free radical processes in liver tissue under the exposure to coal-rock dust on the body (experimental study)

Introduction. Damage to the liver under the conditions of long-term exposure to coal-rock dust on the body leads to significant impairment of its metabolic, detoxification, synthetic, and other functions. In this regard, it is relevant to search for early methods of prevention and correction of developing pathological changes in this organ. The purpose of the study is to experimentally study the effect of a complex drug with dihydroquercetin on the activity of free radical processes in the liver of laboratory rats over the dynamics of long-term exposure to coal-rock dust. Materials and methods. The work was carried out on male white rats weighing 200–250 g. The control group was kept under the standard vivarium conditions. The experimental group included rats that inhaled coal-rock dust in a priming chamber daily for 4 hours for 1, 3, 6, and 9 weeks and rats that received a daily complex drug with dihydroquercetin immediately before dust exposure. In the liver tissue, the activity of free radical oxidation and antioxidant defense enzymes (superoxide dismutase and catalase) was determined. Results. Priming rats with coal-rock dust for three weeks led to the gain in the intensity of free radical processes in the liver tissue: the initial level of accumulation of TBA-active oxidation products reliably raised by almost 2 times over the 1st week and 3 times over the 3rd week of the experiment compared to the control. An increase in the intensity of free radical oxidation was accompanied by activation of antioxidant defense enzymes - catalase - by 2.4 times at the 1st week and 1.6 times at the 3rd week of dust exposure. Raising the period of priming with dust up to 9 weeks led to multidirectional changes in oxidative metabolism in the liver tissue: at week 6, a decrease in the activity of superoxide dismutase was almost 3 times; at week 9, to a slight activation of antioxidant enzymes: superoxide dismutase by 55% and catalase by 36%.The most effective use of a complex drug with dihydroquercetin had been shown in short-term mode for three weeks, but not long-term (more than 6 weeks). The maximum antioxidant defense effect of dihydroquercetin was detected at the 3rd week of dust exposure – the level of free radical products decreased by 2 times and the activity of superoxide dismutase increased by 4 times. Limitations. Since the issue of organ-specific effects and the optimal duration of use of dihydroquercetin to increase resistance to free radical damage has been little elaborated, this imposes certain restrictions on its use for the correction and prevention of occupational diseases. Conclusion. The results obtained should be taken into account with long-term use of exogenous antioxidants in the correction and prevention of occupational diseases to support the level of endogenous antioxidant systems in the cell and the protective effect of dihydroquercetin for tissues most sensitive to the action of free radical processes.

Enzymatic and non-enzymatic link components of antioxidant defence in subcellular fractions of rat liver under the influence of diethyl phthalate

Background. The antioxidant system is one of the protective cell systems. Changes in its functioning, after the introduction of xenobiotics into the body, will determine the further course of the intensity of free radical processes. Among xenobiotics, a prominent place belongs to phthalates, in particular diethyl phthalate (DEP) – the most common group of synthetic substances that are widely used as plasticizers in various industries. Materials and Methods. For a series of experiments, white outbred rats were used, and cytosolic and microsomal fractions were isolated from the liver cells. The activity of such antioxidant enzymes as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), glutathione peroxidase (GSH-Px, EC 1.11.1.9), glutathione S-transferase (GST, EC 2.5.1.18), and the concentration of reduced glutathione (GSH) were determined in the cytosolic fraction. GST activity was also studied in the microsomal fraction. Results and Discussion. The administration of different doses of DEP for 14 days promoted the activation of antioxidant enzymes, regardless of the dose of xenobiotic administration. The use of DEP for 21 days led to a multidirectional effect of the xenobiotic on the enzymes of the antioxidant system in liver cells. The inactivation of the studied enzymes and depletion of the GSH pool were observed when DEP was administered at a dose of 5.4 mg/kg of body weight. The activity of antioxidant enzymes in liver subcellular fractions remained at a high level compared to the control when DEP was administered at a dose of 2.5 mg/kg of body weight. It was established that the same trend of changes in GST enzyme activity was found in both the microsomal and cytosolic fractions of rat liver. The activity of the enzyme increased under the influence of both studied doses under the administration of DEP for 14 days. Administration of the xenobiotic for 21 days led to a decrease in GST activity when a high dose of DEP was administered. Conclusion. The activation of antioxidant system enzymes occurs in response to a short-term intake of DEP. With an increase in the dose and duration of administration of the studied xenobiotic, inactivation of antioxidant enzymes was detected.

Активність ензимів поліольного шляху у нирках щурів за умов різної забезпеченості раціону протеїном і сахарозою

The study examined the activity of enzymes in the polyol pathway and the status of free radical processes in the kidneys of rats subjected to different dietary protein and sucrose levels. It was found that the kidneys of animals consuming a highsucrose diet, irrespective of protein content, exhibited the highest increase in the activity of polyol pathway enzymes, namely aldose reductase and sorbitol dehydrogenase. Consumption of a high-sucrose diet enhances the generation of O2 •- in the kidneys by almost twofold, and hydroxyl radical by over fourfold compared to control indicators. This is accompanied by a twofold increase in the content of TBARS-active products and a threefold increase in the content of carbonyl derivatives of proteins, against the background of a decrease in the content of free thiol groups in proteins. The pronounced generation of hydroxyl radicals, accumulation of TBARS-active products, and reduction in the content of free SH-groups in proteins are characteristic of animals that consumed a high-sucrose diet in the context of dietary protein deficiency. It has been demonstrated that excessive sucrose consumption is a critical factor, influencing the activity of enzymes in the polyol pathway and the intensity of free radical processes. The obtained results may be considered as predisposing factors for disruptions in the structural and functional organization of the kidneys under conditions of nutrient imbalance.

Chemiluminescent Analysis of Oxidative Metabolism in Rat Blood under the Influence of Argon and Helium.

We studied the nature of the action of course treatment with argon and helium (1 min, 3 procedures) on the oxidative metabolism in rat blood plasma. The study was performed on 30 Wistar rats divided into 3 groups (n=10 in each group): intact and 2 experimental (treatment of the skin of the back with a stream of argon and helium, respectively). After completion of the treatment course, the intensity of free radical processes, the total antioxidant activity, and malondialdehyde concentration were evaluated in the blood plasma. It was found that argon and helium gas flows provide stimulation of antioxidant systems, but the mechanisms of their effect were different. Treatment with helium did not affect the intensity of free radical processes, but significantly increased the overall antioxidant activity of blood plasma and reduced malondialdehyde concentration in comparison with the effect of argon flow.

A STUDY OF THE EFFECT OF SAUNA ON THE OXYGEN TRANSPORT FUNCTION OF YOUNG ATHLETES ENGAGED IN HANDBALL SPORT

The effect of sauna on blood oxygen transport function, lipid peroxidation, prooxidant-antioxidant balance in athletes aged 17-21 engaged in handball sport was studied in the article. Persons involved in the hot air sauna were exposed once a week (20 procedures) for a period of four months. The sauna procedure (at 85-90°C, 10-15% humidity) consisted of two parts: 5 and 10 minutes. In young handball athletes, after taking a dry air bath, an increase in pO2, which is the development of respiratory alkolosis, and a decrease in the combination of hemoglobin and oxygen in venous blood increased the amount of oxygen transported to tissues. After a one-time exposure to the sauna, the development of oxidative stess accelerated (intensification of free radical processes, weakening of antioxidant defenses), and at the end of the course it began to decline. The observed increase in the formation of nitric oxide can play an important role in the modification of oxygen-dependent processes in the body.

Metabolic Effects of Electromagnetiс EHF Radiation and Ozone Therapy in the Engraftment of the Skin Flap

The aim of this study was to evaluate the effect of ROS on the intensity of oxidative and energy metabolism in the blood of rats with an operational model of ischemia of the dorsal skin flap in vivo. Our studies have allowed us to establish that the modeling of an extensive skin defect is accompanied by pronounced shifts in oxidative metabolism in the blood plasma of animals. At the same time, in the absence of pathogenetic treatment, signs of oxidative stress are formed, including the intensification of free radical processes and the inhibition of general antioxidant activity in combination with the accumulation of an increased amount of lipoperoxidation products (in particular, malondialdehyde). Conducting experimental therapy with the introduction of ozone or treatment with electromagnetic radiation of the EHF band allows partially compensating for these metabolic disorders, however, the most optimal option is a combination of these factors within a single scheme. It should be noted that the results obtained are of great applied importance for the creation of innovative technologies for the complex medical rehabilitation of orthopedic-traumatological patients as a tool for influencing reparative processes in the lesion to restore and maintain tissue structures.

Experimental study of morphological changes in the heart and blood vessels in the course of chronic fluoride intoxication

Introduction. Clinical studies have shown the development of a complex of non-specific changes in internal organs due to chronic fluoride intoxication. The accumulation of fluorine in the body initiates free radical oxidation, promotes the development of pathological processes in the heart against the background of an imbalance between pro- and antioxidants, and vascular endothelial dysfunction. Pathological activation of intima cells leads to unbalanced production of damaging factors, changes in the hemostasis system, and entails morphological and functional disorders of organs.
 Materials and methods. The experiments were carried out on one hundred twenty white male rats. A morphological study of the heart, blood vessels was performed out at 1, 3, 6, 9 and 12 weeks of chronic fluoride intoxication.
 Results. The 1st-3rd weeks of the experiment are characterized by the preservation of the morphological structure of the cardiac muscle against the background of the previously shown a compensatory activation of the components of the redox-signalling system, which provided a decrease in the intensity of free radical processes. With an increase in the duration of exposure to sodium fluoride (6–9 weeks) these mechanisms failure was noted, which was manifested by the development of degenerative changes in the myocardium, progressing up to the 12th week of the experiment. The described changes correlated with the development of endotheliosis, degenerative and fibroplastic processes, circulatory disorders in the vessels of the heart and other organs.
 Limitations. Histological findings are descriptive.
 Conclusion. The results obtained are of practical importance for the elaboration of effective methods for timely organ-protective prevention and correction of pathomorphological disorders, depending on the organ-specific features and duration of fluoride intoxication.

The intensity of free radical processes and chaperone activity in the saliva of patients with type 2 diabetes.

Saliva is a clinically informative biological fluid that contains many biomarkers, allowing multiple analyses to be performed. The objectives of this study were the assessment of the serum and saliva levels of biochemical parameters and intensity of free radical processes in T2DM patients and the identification of the correlation between certain criteria. This case-control study included 40 T2DM patients, which were compared with 40 healthy individuals. The levels of glucose, cholesterol triglycerides, total protein, diene conjugates, and chaperone activity were measured using the spectrophotometric method. The concentration of 8-oxo-2'-deoxyguanosine was assessed by competitive enzyme-linked immunosorbent assay. It was established that the progression of diabetes led to an increase in glucose in saliva. The content of 8-oxo-2'-deoxyguanosine and conjugated dienes increased in serum and this increase was associated with the level of glucose and glycated hemoglobin. The level of protein and chaperone activity increased in the saliva of patients with T2DM compared with the control. The correlation analysis revealed a relationship between total protein concentration and conjugated dienes and between chaperone activity and conjugated dienes in saliva. According to the results of the analysis, the pathological changes in DM affected the salivary glands and their secretions. The obtained results allowed us to recommend using saliva as an alternative to blood for the diagnosis and monitoring of T2DM treatments since it is readily available and quickly responds to changes in metabolism in the body.

ЕКСПРЕСІЯ ГЕНІВ PTGS2 ТА NOS2 У СИНОВІАЛЬНІЙ РІДИНІ ХВОРИХ НА ОСТЕОАРТРИТ ПІСЛЯ SARS-CoV2-ІНФЕКЦІЇ

Background. The emergence of a new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) has created a serious global threat to the health of people in various countries. The 2019 coronavirus disease (Coronavirus disease 2019, COVID-19) has caused the development of many complications in the population of most countries of the world. Currently, many people have felt the unpleasant consequences of the coronavirus infection. Among them, a special group consists of patients with chronic diseases, particularly osteoarthritis. The development of inflammation and intensification of free radical processes is a leading link in the pathogenesis of osteoarthritis. Inflammatory and degenerative processes that develop in osteoarthritis cause modification of the molecular and cellular composition of the synovial fluid. Methods. The aim of the work was to determine the expression of (Prostaglandin-endoperoxide synthase 2) and NOS2 (Nitric Oxide Synthase 2) genes in synovial fluid cells of patients with osteoarthritis after SARS-CoV2 infection. All study participants were divided into two groups. The first group (n = 22) is patients with osteoarthritis of the knee joints II-III degree. The second group (n = 14) is patients with osteoarthritis of the knee joints II–III degree, who suffered a mild and moderate form of COVID-19 6–9 months ago. Expression of PTGS2 and NOS2 genes was determined in nuclear cells of synovial fluid. RNA was obtained by the Chomczynski method. Synthesis of cDNA and quantitative polymerase chain reaction in real time (Real-time PCR, qPCR) using the commercial kit "Thermo Scientific Verso SYBR Green 1-Step qRT-PCR ROX Mix" ("Thermo Scientific, Lithuania). Processing of research results was carried out using generally accepted methods of variational statistics. Results. In patients with osteoarthritis of the knee joints after SARS-CoV2 infection, the expression of PTGS2 and NOS2 genes increases in nuclear cells of the synovial fluid compared to patients diagnosed with osteoarthritis. Conclusions. Our results indicate that patients with osteoarthritis may develop a more severe course of synovial inflammation after infection with COVID-19.

ИНТЕНСИВНОСТЬ СВОБОДНО-РАДИКАЛЬНЫХ ПРОЦЕССОВ И СТРУКТУРНО-ДИНАМИЧЕСКИЕ ПА-РАМЕТРЫ МЕМБРАН ЭРИТРОЦИТОВ БОЛЬНЫХ САХАРНЫМ ДИАБЕТОМ 2 ТИПА

The World Health Organization has recognized diabetes mellitus (DM) as one of the four major noncommunicable diseases that lead to early disability and mortality among the population. Oxidative stress, which contributes to the intensification of free radical processes (FRP), can be considered as a universal nonspecific mechanism of DM2 pathogenesis. De-spite numerous studies, questions about the mechanisms of development of oxidative stress and its influence on the physicochemical state of biological membranes still remain open. The aim of this work is to study the intensity of free radical processes and the structural and dynamic characteristics of blood erythrocyte membranes in patients with type 2 diabetes mellitus (DM2). The study included male patients with type 2 diabetes aged 55 to 70 years who did not have other acute and chronic diseases in the acute stage. The content of glucose, glycated hemoglobin, markers of oxidative stress (MDA and carbonyl groups) was determined in the blood of patients. The structural and dynamic parameters of erythrocyte membranes were determined using fluorescent probe pyrene. It was found that an increase in blood glucose levels in patients with DM2 increases the content of markers of lipid peroxidation (MDA) and oxidative modification of proteins (carbonyl groups). Oxidative damage to lipids and proteins of erythrocyte membranes in decompensated DM2 changes their structural and dynamic properties: they increase the microviscosity of the lipid bilayer and the polarity of its phospholipids, and promote conformational rearrangements in membrane proteins. Close correlations were found between the level of glucose, the content of CRP products in the blood, and the structural and dynamic parameters of erythrocyte membrane

Інтенсивність вільнорадикальних процесів у скелетних м’язах щурів за умов різної забезпеченості раціону нутрієнтами

The intensity of free-radical processes in the skeletal muscles of rats at different dietary supply with protein and sucrose was studied. It has been established that the most pronounced intensification of free radical processes in the mitochondria of skeletal muscles is found in animals kept on a low-protein/ high-sucrose diet. In particular, the generation of superoxide anion-radical increases more than 5,3-fold and the generation of hydroxyl radical more than 3,2-fold compared with the control, more than a 14,3-fold increase in the carbonyl derivatives levels, and also decreases by three times in the free protein SH-groups levels against the background of a 1,7-fold decrease in catalase activity. It has been shown that excessive consumption of sucrose is a critical factor influencing the intensity of free radical processes in skeletal muscle mitochondria. The detected changes can be considered as prerequisites for skeletal muscle dysfunction under the conditions of nutrient imbalance.

Evaluating Some Parameters Of Wistar Rat Brain In Traumatic Brain Injury Model With Administration Of Proline-Containing Peptides

Objective — To examine the morphometric parameters of neurons and the oxidative status of the Wistar rat brain tissues after administering proline-containing peptides, also known as glyprolines (Arg-Gly-Arg-Pro-Gly-Pro [RGRPGP] and Thr-Lys-Pro-Arg-Pro-Gly-Pro [WKPRPGP; Selank]), on a traumatic brain injury (TBI) model. Study subjects — Our study involved 26 mature male Wistar rats (2.5-3 mos. old, 220-300 g). The morphometric parameters of neurons and the oxidative status of animal brain tissues were studied. Material and Methods — Four experimental groups were formed. Group 1 included intact control animals. Animals in three other groups were subjected to TBI via free fall of a 50 g weight from a height of 50 cm on the second day of the experiment and received the following injections: 0.9% sodium chloride solution in Group 2; WKPRPGP peptide solution in Group 3; RGRPGP peptide solution in Group 4. Substances were administered intraperitoneally on a daily basis at a dose of 0.1 mg/kg from day 1 through day 5 of the experiment. Morphometric parameters of rat brain neurons were studied on paraffin sections stained with hematoxylin and eosin. The intensity of free radical processes in the brain tissue was investigated by chemiluminescence. Results — An analysis of morphometric parameters revealed significant increases in the neuronal cytoplasm area, nucleolar area, number of nucleoli, and nuclear-nucleolar index with the introduction of the RGRPGP peptide after TBI, compared with the WKPRPGP peptide under the same conditions. After TBI and peptide administration, we observed an oxidative stress in the neocortex of Wistar rats, and it was more pronounced in the group of animals treated with RGRPGP. Conclusion — After RGRPGP peptide administration, we observed an increase in the morphometric parameters of neurons in the closed TBI model: a larger area and a greater number of nucleoli. Chemiluminescence data implied that WKPRRPGP peptide better protected brain tissue in rats from the effects of oxidative stress caused by TBI.

Chemiluminescence analysis of free radical processes in seminal plasma of men with pathospermia who have undergone COVID-19 infection

Introduction. In the context of the COVID-19 pandemic, it seems relevant to study the clinical features and the effect of the SARS-CoV-2 virus on the reproductive system and male fertility.The study objective was to assess the intensity of oxidative processes in the seminal plasma of men with pathozoospermia after suffering a COVID-19 infection.Materials and methods. Spermogram parameters were assessed in accordance with the criteria of the 2010 WHO Guidelines, 5th edition, for the study and processing of human ejaculate two to three months after the patient received a negative polymerase chain reaction result of a nasopharyngeal swab for SARS-CoV-2 DNA. The intensity of free radical processes in seminal plasma was investigated by the method of chemiluminescence induced by ions of bivalent iron. Results. A decrease in sperm motility and an increase in the number of leukocytes were found in men with pathozoospermia who had undergone COVID-19 infection. There are lower levels of indicators such as ejaculate volume, total sperm concentration and the number of morphologically normal sperm forms. An increased ability to generate reactive oxygen species in seminal plasma was revealed in pathozoospermia and COVID-19.Conclusions. The results obtained indicate that SARS-CoV-2 affects the male reproductive system directly or indirectly and has a negative effect on male reproductive health, causing the activation of lipid peroxidation processes and spermatogenic insufficiency.

Experimental Evaluation of the Effect of Argon Cold Plasma on Oxidative Metabolism of the Blood.

We studied the effect of course exposure to argon cold plasma (ten 1- and 2-min procedures) on some parameters of the oxidative metabolism of rat blood plasma. The intensity of free radical processes, the total antioxidant activity, and malondialdehyde concentration in rat plasma were evaluated. It was found that 2-min exposure to argon cold plasma and nonionized argon stream produce a prooxidant effect, while 1-min exposure argon plasma led to stimulation of the antioxidant reserves of the blood.

ПЕРЕКИС НЕОКИСНЕННЯ ЛІПІДІВ У СИНОВІАЛЬНІЙ РІДИНІ ХВОРИХ НА ОСТЕОАРТРИТ ПІСЛЯ SARS-CoV2-ІНФЕКЦІЇ

The 2019 coronavirus disease (Coronavirus disease 2019, COVID-19) poses a great threat to the health of people in all countries of the world. Infection with SARS-CoV-2 (Severe acute respiratory syndrome-related coronavirus 2) is a respiratory disease characterized by the development of severe life-threatening complications. COVID-19 is more likely to be severe and sometimes fatal, especially in older people with co-morbidities. A topical issue is predicting the course of chronic diseases in people who have contracted a coronavirus infection. An increasing number of cases of arthritis associated with COVID-19 have been reported in the literature, making this condition worthy of further study. It is known that the development of osteoarthritis is associated with oxidative stress and excessive production of reactive oxygen species. Lipid peroxidation products can serve as a marker of the intensity of free radical processes. The aim of the study was to determine the concentration of lipid peroxidation products in the synovial fluid of patients with osteoarthritis after SARS-CoV2 infection. All study participants were divided into two groups. The first group (n=22) is patients with osteoarthritis of knee joints II-III degree. The second group (n=14) is patients with osteoarthritis of the knee joints II-III degree, who suffered a mild and moderate form of COVID-19 6-9 months ago. In the conducted studies, the products of lipid peroxidation in the synovial fluid of patients of all research groups were evaluated.The content of diene conjugates was determined in the heptane-isopropanol extract by the spectrophotometric method, Schiff bases by the fluorimetric method. The content of TBA-active products was determined by the reaction with thiobarbituric acid (TBA). The processing of the research results was carried out using generally accepted methods of variational statistics. It was established that in the synovial fluid of patients with osteoarthritis of the knee joints who contracted COVID-19, the concentration of lipid peroxidation products increases compared to the group of patients with osteoarthritis (diene conjugates – by 1.7 times, TBА-active compounds – by 1,5 times, Schiff bases – 1.3 times). The detected changes indicate a violation of the oxidative-antioxidant balance. This indicates the prevalence of free radical processes and the development of oxidative stress directly in the joint. The results obtained by us indicate that patients with osteoarthritis may develop more severe joint damage and complications after infection with COVID-19.

ДИНАМИКА ИЗМЕНЕНИЙ ПОКАЗАТЕЛЕЙ ОКИСЛИТЕЛЬНОГО ГОМЕОСТАЗА В ПРОЦЕССЕ РЕПЕРФУЗИИ ПЕЧЕНИ КРЫС ПОСЛЕ ВАСКУЛЯРНОЙ ЭКСКЛЮЗИИ

Changes in the state of the antioxidant protection system and the intensification of free radical processes are the leading pathobiochemical mechanism for the development of reperfusion damage to cells. The aim of this paper is to determine the features of changes in markers of oxidative stress at different periods of development of the acute reperfusion after total vascular exclusion of rat liver. The study was carried out on 100 white nonlinear sexually mature male rats weighing of 200-250 grams. The animals of the experimental groups were simulated with a 20-minute vascular isolation of the liver. Blood in a volume of 2-3 ml was taken from the inferior vena cava for 5, 15, 30, 60, 120, 180 minutes, 8 hours and a day after the restoration of blood flow. The results of the study showed that in the early stages of the reperfusion period (5-60 minutes), changes are observed due to cytolysis of hepatocytes during the period of organ ischemia and leaching of cell contents into the blood. The level of radical sorption of ABTS by blood plasma briefly increased by 20% by the 5th minute of the reperfusion period; at the same period, an increase in glutathione peroxidase activity by 2.5 times was noted. The total antioxidant activity, determined by the iron-reducing method, was increased by 2 times within the period of 15-30 minutes after the restoration of blood flow. The main manifestations of reperfusion damage to the liver developed in 60 minutes after the restoration of blood flow and were characterized by a sharp decrease in total AOA by 1.5-2 times and the concentration of reduced glutathione by 20%. The system of antioxidant protection of blood plasma was the first to react to the spread of the pathological process at the systemic level and its changes persisted one day after liver ischemia. A 20-minute vascular exclusion of the liver was accompa- nied by changes in the antioxidant balance in the erythrocyte suspension, but these changes returned to normal a day after the restoration of blood flow. The data obtained make it possible to distinguish between the contribution of ischemic and reperfusion injuries to the development of oxidative disorders, which is important from the standpoint of assessing the possibilities of anti- oxidant therapy.

Relationship between indicators of insulin resistance and oxidative balancein adolescents with androgen deficiency

The purpose of the work was to study the relationship between the indicators of insulin resistance (IR), free radical oxidation products (FRO) levels, and the antioxidant system activity in adolescents with androgen deficiency (AD).Materials and methods. 58 adolescents 13­—18 years old with AD were examined. Serum levels of total testosterone, glucose, insulin, tiobarbituric acid active compounds (TBA), carbonylated proteins (CB), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activity were determined. The HOMA index and the coefficient of oxidative stress were calculated.Results and discussion. In the group of adolescents with AD without IR, an inverse correlation was found between the HOMA index and CAT activity. CAT activity negatively correlated with CB content and glucose concentration. In addition, an inverse relationship was found between the activity of GPO and SOD. IR indices indirectly, through feedback with the activity of CAT, influence to the formation of conditions for inhibition/activation of FRO of proteins.IR was revealed in 37.9 % of the examined adolescents with AD. Direct relationship was recorded between IR indicators and markers of oxidative stress, as well as between testosterone levels and GPx activity in the group of these patients. Direct correlation between the coefficient of oxidative stress and the content of TBA-­active compounds indicates the formation of oxidative stress due to the activation of lipid peroxidation. Reduced testosterone levels in adolescents with AD inhibits an increase in GPx activity and prevents compensation for excessive intensity of free radical processes. Conclusion. The results indicate that adolescents with AD have a close relationship between the processes of carbohydrate metabolism, FRO, and antioxidant protection.In adolescents with AD without IR, a balancebetween the studied parameterswas found.The formation of IR in adolescents with AD shifts the equilibrium of the oxidative balance towards the activation of FRO processes. Decreased testosterone levels in adolescents with AD do not maintain the body’s antioxidant status within normal limits.

Lipid peroxidation and antioxidant defense system in patients with kidney cancer

Purpose of the study: to assess the state of lipid peroxidation processes in patients with kidney cancer in relation to the clinical factors of the prognosis of the disease and against the background of surgical intervention.Material and methods. For the study, we used blood plasma samples from 300 patients with kidney cancer T1–4N 0–1M0–1, obtained before surgery and 8–9 days after surgery. Oxidative stress was assessed by the intensity of free radical processes by the method of induced biochemiluminescence on the BKhL-07 biochemiluminometer apparatus (Medozons Co., Russia), the activity of lipid peroxidation processes was assessed by the accumulation of initial products in the blood plasma – diene conjugates (DC), triene conjugates (TC) and fial Schiff bases (OSh) according to I. A. Volchegorsky et al. method. (1989). Statistical processing of the results was carried out using Statistica 12 and Microsoft Offie Excel 2010 programs.Results. In patients with kidney cancer, there was a decrease in the level of DC, an increase in OSh and the ratio of Osh / (DC + TC) compared with the control (p ≤ 0.05), against the background of depletion of the resources of the antioxidant defense system. The content of DC did not differ from the norm with the size of the primary tumor of the kidney pT1–pT2 and decreased (p ≤ 0.05) in the case of the presence of the tumor pT3–pT4. At the same time, there was an increase in the OSh content (p ≤ 0.05). In patients with thrombi in the inferior vena cava system, a decrease in the level of DC was observed (p ≤ 0.05), the OSh level did not differ from that of healthy individuals. In the postoperative period, there was an increase in the content of DC (p ≤ 0.05) and a decrease in the Osh / (DC + TC) coeffiient (p ≤ 0.05) compared with the initial level.Conclusion. Kidney cancer is accompanied by the activation of free radical oxidation processes against the background of depletion of the resources of the antioxidant defense system. Changes in the pro-antioxidant homeostasis are interrelated with the size of the primary tumor and the presence of a tumor thrombus. In the postoperative period, the activity of free radical oxidation processes in the patient’s body decreases.