Free Radical Oxidation Processes Research Articles

Influence of impulse magnetic fields of extremely low frequencies on H2O2- and Fe2+-induced free radical lipid oxidation in liposomal suspensions

Background: For a long time, special attention in experimental biology and medicine is paid to free radical processes involving reactive oxygen species. In electromagnetic biology, the interest in free radical oxidation in biological membranes has increased significantly due to the discovery of spin mechanisms of magnetic fields on free radical processes. In the present day, these mechanisms are considered to be key in the processes of magnetoreception in living organisms. Liposomes, as the simplest models of biological membranes, are often used to study the primary mechanisms of action of different factors on the structural and functional properties of membranes. However, the influence of ecological significant extremely low-frequency magnetic fields on free radical oxidation in liposomal suspensions has not been studied enough. Objectives: The elucidation of the peculiarities of the influence of the extremely low frequency pulsed magnetic fields (ELF PMF) on H2O2- and Fe2+-induced peroxidation of natural phospholipids in liposomal suspensions. Materials and methods: The liposomal suspensions in phosphate buffer pH=7.4 were used. According to the literature and own results on light scattering the average diameter of liposomes was about 500Å. Ultra-weak chemiluminescence of liposomal suspensions was recorded using a device that operated in the mode of single photons counting. It consisted of a light-insulated cuvette unit where the test samples were placed, as well as a temperature sensor and a solenoid, which was used to create the PMF. Optical contact of the test samples with the photoelectron multiplier was carried out using a light guide. The recording system consisted of a broadband photomultiplier tube detector — FEU-130, which was at a temperature of –20°C. The pulse analyzer AI-256 was used to separate the useful signal that corresponded to the registration of single chemiluminescence light quanta. The voltage on the photomultiplier tube detector was applied in the range of current-voltage characteristics of this detector, in which a random voltage fluctuation had a minimal effect on the measurement of the useful signal. The number of light quanta that were recorded for defined time intervals characterized the overall intensity of the process of free radical oxidation of lipids in the experimental samples. The pulsed magnetic field was created using a solenoid coil located in the cuvette part. PMF was created using a serial generator G6-28. The magnetic field pulses were rectangular in shape with variable polarity for a period of oscillations. The induction of PMF was monitored using microteslameter G-79. The series of extremely low frequencies (5–80 Hz) and induction (5–500 μT) of PMF was chosen due to their environmental and physiological significance. Results: PMF of different frequencies with induction of 5 and 50 μT did not affect (p>0.05) H2O2- and Fe2+-induced lipid oxidation in liposomal suspensions. Statistically significant changes (p<0.05) were revealed only when liposomal suspensions were exposed to PMF with induction of 500 μT. It was found that the action of PMF with the frequency of 8 Hz 500 μT significantly inhibited H2O2-induced and enhanced Fe2+-induced chemiluminescence. This effect is associated with inhibition of the decomposition and with the accumulation of phospholipid hydroperoxides, which decompose and recombine in the presence of Fe2+ ions, which is accompanied by stronger chemiluminescence. The study of the dependence of the dynamics of the chemiluminescence intensity on the frequency of the PMF indicates the presence of a certain dependence of the effects in the range of up to 30 Hz. However, the inhibitory effect of PMF for the H2O2-induced oxidation phase is not always accompanied by a statistically significant increase in the amplitude of Fe2+-dependent light flash of chemiluminescence that indicates the general inhibitory effect of PMF at a certain frequency. Conclusions: PMF of extremely low frequencies statistically significantly affects the free radical oxidation in liposomal suspensions only at inductions exceeding several hundred microteslas. This indicates the effect of PMF on free radical processes for the conditions of the selected membrane model is realized mainly through spin interactions that determine the recombination of free radicals. The decrease of induction by one or two orders of magnitude, as well as increasing in frequency of the PMF above 50 Hz, leads to a decrease in the effectiveness of the influence of this physical factor on the intensity of lipid-free radical oxidation in liposomal suspensions. The most sensitive to the influence of ELF PMF is the phase of H2O2-induced free radical oxidation of lipids.

The use of plants with high antioxidant activity in cooking

The quality of food has a significant impact on human health and longevity. Antioxidants are found in large quantities in herbaceous plants. Therefore, foods with high antioxidant activity can be considered one aspect of their quality. Antioxidants, in turn, are a form of activity that inhibits the free-radical oxidative processes that occur in living organisms. Consumption of foods high in antioxidants helps maintain normal human health. Antioxidants are used as food supplements or in prepared meals. Therefore, this article discusses the preparation of food using herbs with high antioxidant activity, based on which the antioxidant content of the finished food, vitamin E indicators. Especially in terms of antioxidant content, it is contained in higher amounts in sweet mint bread products than in dill.

AGE PECULIARITIES OF PROOXIDANT-ANTIOXIDANT BALANCE OF THE ORAL FLUID IN PATIENTS AGAINST THE BACKGROUND OF INTAKT DENTITIONS, PARTIAL AND COMPLETE ANODONTIA

Relevance. The study is conditioned by a steady tendency of demographic aging of the population. On the part of the dental system, one of the most common age-related disorders is the tooth loss and the necessity to replace dentition defects. Changes in dental status can affect the course of oxidative reactions and antiradical protection of the oral fluid.
 Objective is to investigate the age peculiarities of the prooxidant-antioxidant balance of the oral fluid against the background of intact dentitions, partial and complete anodontia and their correction.
 Material and methods. There were examined 103 patients aged from 16 to 89, with intact dentitions, under the conditions of partial anodontia and correction with bridges or partial removable laminar dentures and complete anodontia and correction with complete removable laminar dentures. The intensity of the processes of free radical oxidation of lipids in oral fluid was assessed by the content of diene conjugates (DC) and products that respond to thiobarbituric acid (TBA-AP). The antioxidant reserve of the oral fluid was characterized according to the activity of superoxide dismutase (SOD), glutathione peroxidase (GP) and glutathione reductase (GR).
 Results. There was a significant increase of the indices of lipid peroxidation in the oral fluid, especially in middle-aged patients, which is confirmed by an increase in the content of DC and TBA-AP 5.9- and 4.5-fold, respectively, compared with data in adolescents. Such changes were consistent with a decrease in the activity of SOD, GP, GR of the oral fluid at 41.7-48.8% (p<0.05) relative to the values ​​in adolescence. In elderly and senile patients, the level of lipid peroxidation tended to decrease. The activity of antioxidant enzymes in elderly patients decreased at 28.6-49.8% (p<0.05), in the senile patients – at 29.6-63.6% (p<0.05) relative to the values ​​in the middle-aged patients. There has been an increase in the level of oxidative processes against the background of suppression of antiradical protection of the oral fluid in patients with partial or complete anodontia according to the data in the studied patients with intact dentitions, especially for people who use dentures.
 Conclusions. Prooxidant-antioxidant balance of the oral fluid depends on age and dental status. The most significant changes in oxidative processes in the oral fluid are observed in the middle-aged people with a tendency to decrease in the elderly and senile patients. The level of free radical processes increases under the conditions of partial and complete anodontia, correction of various types of denture designs and depends on the material they were made of. Such changes occur against the background of suppression of the antioxidant reserve of the oral fluid (especially the glutathione system).

Oxidative balance disorders as a factor of formation and progression of hypoandrogenism in boys

Objective — to study the features of the state of oxidative balance (processes of free radical oxidation and antioxidant protection) in boys with hypoandrogenism (HA). Materials and methods. Examinations involved 103 adolescent boys agreed 14 to 17 years with the delayed sexual development. Serum levels of total testosterone (TT), conjugated dienes (CD), thiobarbituric acid­reactive substance (TBARS), carbonylated proteins, reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) activity were determined. The coefficient of oxidative stress was calculated. Results and discussion. The following indicators have been revealed in patients with the delayed sexual development vs the comparison group: increased CD levels in 84.0 % of patients, elevated levels of carbonylated proteins in 53.7 % of adolescents, one third had raised TBARS levels; 63.0 % of patients demonstrated the increased GSH levels. Decreased activity of GPx and CAT was registered in more than half of the patients. Such changes indicate an imbalance in the ratio of free radical oxidation (FRO) and antioxidant protection, which leads to the state of OS in adolescents with delayed puberty.It was found that the redox balance in adolescents with delayed puberty significantly depends on the degree of androgen deficiency. Half of the patients with a degree I and II HA and 24.5 % of boys with degree III HA had elevated TBARS levels, which is more common in adolescents with normative values of TT. At the highest degree of androgen deficiency, the frequency of normative values of carbonylated proteins decreased. Most boys had elevated levels of CD (80 %), regardless of the degree of HA. An increase in SOD activity was found in patients with degree III HA. Low SOD activity was registered in 28.6 % of patients with degree II HA and 29.6 % with degree III HA, which is much less common compared to patients with normal TT levels. Most patients with HA, regardless of degree, were characterized by low GPx activity. Decreased CAT activity was registered in 76.9 % of patients with degree II HA. The majority of patients with HA (from 60.9 to 90 %) showed elevated levels of GSH, regardless of degree. The progression of HA in adolescents is characterized by the accumulation of products of free radical oxidation of lipids and an imbalance in the enzymatic and low molecular parts of the antioxidant system. This is typical for HA II and III degrees. The largest number of correlations was found in patients with degree III HA, testifying the formation of oxidative stress due to the activation of lipid peroxidation with simultaneous tension of the antioxidant defense system. Conclusions. The progression of HA is accompanied by the accumulation of products of free radical oxidation of lipids with simultaneous depletion of the enzymatic part of the antioxidant defense system. The activating effect of testosterone deficiency on the formation of oxidative stress in adolescents with the highest degree of androgen deficiency has been proven. This makes it possible to assess the state of oxidative balance as a factor in the formation and progression of HA in adolescents.

Visible-LED-light-driven photocatalytic activation of peroxydisulfate by magnetic ZnFe2O4/Ag nanocomposite for efficient tetracycline degradation

Heterogeneous photocatalysis/persulfate oxidation process has been regarded as a promising technology for antibiotic contaminants removal. Magnetic ZnFe2O4/Ag composite catalyst was synthesized to activate peroxydisulfate (PDS) toward tetracycline (TC) degradation under the visible-LED-light irradiation. The synergistic effect of ZnFe2O4 and Ag endowed the optimized ZFO/Ag-15 with excellent photocatalytic performance for PDS activation and TC degradation, and 90.06 % of TC (20 mg/L) was efficiently degraded after 80 min of reaction. Ag can enhance the visible light absorption of ZnFe2O4 and accelerate the separation of photo-induced electron/hole pairs, thereby promoting the generation of O2− and SO4− radicals. In addition, Ag can directly activate PDS to generate SO4−. Although the catalytic performance of magnetic ZFO/Ag-15 gradually decreased after each cycle due to the corrosion of Ag and the formation of inactive AgO, the catalytic activity of used catalyst was partially recovered by heat treatment. Quenching experiments and EPR tests indicated that the free radical (O2−, SO4− and OH) and non-free radical (1O2, h+) oxidation processes cooperated to degrade TC in Vis-ZFO/Ag-15/PDS system. The effect of operational factors (PDS concentration, temperature, solution pH, coexisting inorganic anions and humic acid) on TC degradation was investigated, and TC removal from the different water matrices (river water, tap water and secondary effluent) was also evaluated. The degradation products were detected using LC-MS and the possible TC degradation pathways were established.

Attacking effect of diabetes mellitus and chronic neurogenic pain on malignant process:Are mitochondria of the heart damaged?

e21557 Background: Mitochondrial dysfunction is one of the mechanisms for the development of heart disease that requires close study. Diabetic cardiomyopathy is the leading cause of death in such patients due to the development of heart failure. Chronic pain may be associated with higher prevalence of cardiovascular disease, and little is known about its potential biological consequences. The purpose of this study was to analyze parameters of free radical oxidation and mitochondrial respiration in heart cells in experimental animals with malignant tumors growing in presence of diabetes mellitus (DM) and chronic neurogenic pain. Methods: The study included outbred female rats (n = 32) weighing 180-220 g and C57BL/6 female mice (n = 84) weighing 21-22 g. Experimental groups of rats were: intact animals (n = 8), controls (n = 8) with DM, comparison group (n = 8) with subcutaneously inoculated Guerin’s carcinoma, and main group (n = 8) with Guerin’s carcinoma subcutaneously inoculated after 1 week of persistent hypothyroidism. Experimental groups of mice were: intact animals (n = 21), controls (n = 21) with a model of chronic neurogenic pain (CNP) created by bilateral sciatic nerve ligation, comparison group (n = 21) with subcutaneously inoculated melanoma (B16/F10), and main group (n = 21) with melanoma subcutaneously inoculated 3 weeks after the CNP model was created (CNP+B16/F10). Heart mitochondria were isolated by differential centrifugation. Levels of cytochrome C (ng/g of protein), 8-hydroxy-2'-deoxyguanosine (8-OHdG) (ng/g of protein), and malondialdehyde (MDA) (nM/g of protein) were measured in mitochondrial samples by ELISA. Statistical analysis was performed using the Statistica 10.0 program. Results: DM in rats upregulated 8-OHdG by 6.3 times and MDA by 1.9 times (p < 0.05) and downregulated cytochrome C by 1.5 times (p < 0.05) in heart cell mitochondria, compared to intact values. DM+Guerin’s carcinoma in rats increased 8-OHdG by 14.0 times and MDA by 1.7 times (p < 0.05) and decreased cytochrome C by 1.5 times (p < 0.05), compared to intact values. CNP in mice did not affect the studied parameters in mitochondria of the heart. CNP+B16/F10 in mice increased 8-OHdG by 7.1 times and MDA by 1.6 times (p < 0.05) and decreased cytochrome C by 1.6 times (p < 0.05) in heart cell mitochondria. Conclusions: Comorbidity (diabetes mellitus, chronic neurogenic pain) together with malignant pathology aggravates mitochondrial dysfunction of heart cells which results in DNA damage and destabilization of the respiratory chain mediated by free radical oxidation processes.

Nephroprotective Effect of Leu-Ile-Lys Tripeptide in Experimental Diabetes Mellitus.

We studied the effect of tripeptide Leu-Ile-Lys on kidney function in rats with experimental diabetes mellitus modeled by single intraperitoneal administration of streptozotocin (65 mg/kg). The tripeptide was intragastrically administrated in a dose of 11.5 mg/kg from week 5 to week 8 of the pathological process. The concentrations of glucose, protein, and creatinine in the urine were measured before and then weekly throughout the experiment. In 8 weeks, the markers of activity of the free radical oxidation process (concentration of TBA-reactive substances, total prooxidant activity, and total antioxidant activity, as well as activities of catalase, superoxide dismutase, and glutathione peroxidase) were assayed and a morphological study was conducted. After administration of the tripeptide Leu-Ile-Lys for 4 weeks, glucose concentration in the urine decreases by 3-44 times (p<0.001) and protein concentration by 2.3-3.7 times (p=0.007). The concentration of TBA-reactive substances decreased by 1.3 times (p<0.001), and the total antioxidant activity increased by 2.3 times (p<0.001). Administration of the tripeptide Leu-Ile-Lys to animals with experimental diabetes mellitus led to significant improvement of the renal function against the background of significant alleviation of oxidative damage and an increase in the antioxidant protection of the renal tissues. Improvement of the morphofunctional state of tissues and cells of the renal glomerulus was confirmed histologically, in particular, an increase in the number of podocytes by 1.5 times was observed.

Liquid Phase Oxidation of Hydrocarbons to High-Value Chemicals in Microfluidic Reactors - Prospects and Challenges.

Liquid phase oxidation (LPO) of hydrocarbon is an industrially important process to produce petrochemicals and pharmaceuticals. It follows a free radical path having initiation, propagation and termination. The initiation step is slow while the propagation and termination steps are fast. The main challenge of such process is to control product selectivity at an appreciable conversion level. With the advancement of microfluidic reactor technology, it is possible to control the free radical steps. The present contribution critically reviewed the reaction engineering aspects of LPO of hydrocarbon, the influence of microfluidic reactor design and operation on reaction mechanism, conversion and product selectivity. It also outlines the challenges associated with microfluidic reactor operation, and prospects to apply the understanding from microfluidic reactors in few sectors. The understanding from the free radical oxidation process can also be applied to any other free radical processes.

Impact of General Anesthesia and Antioxidants on Cognitive, Static and Locomotor Functions During Laparoscopic Cholecystectomy

Aim of the study: to reduce cognitive impairment during laparoscopic cholecystectomy by perioperative administration of drugs with antihypoxic and antioxidant effects under the control of stabilography. Materials and methods. We studied the effect of general anesthesia and antioxidants on cognitive, static and locomotor functions during laparoscopic cholecystectomy. We studied 90 patients with acute calculous cholecystitis randomized into three experimental groups (n=30, each group). The control group was composed of 24 healthy individuals. Group 1 patients received no antioxidants, group 2 patients received the combination antioxidant drug (sodium fumarate+sodium chloride+potassium chloride+magnesium chloride) in the post-operative period, and group 3 patients received methylethylpyridinol. The patient groups were comparable in sex, age and type of inflammatory and destructive process in the gallbladder. Surgical intervention was performed under endotracheal anesthesia. Premedication with atropine and promedol was given, and anesthesia induction was carried out with propofol, fentanyl and suxamethonium. Sevoflurane, fentanyl andcisatracurium were employed to maintain anesthesia, analgesia and myorelaxation, respectively. The patients were examined before surgery, 24 and 48 hours after surgery. In the groups of patients who received antioxidant therapy, blood sampling for hematological and biochemical examinations was performed 30 min after the administration of antioxidants. Stabilographic studies and MoCA test (Montreal Scale) were performed before antioxidant administration prior to surgery and after surgery, on days 2 and 3. Results. Neuropsychological testing revealed postoperative cognitive dysfunction on standard therapy which included impaired attention and concentration, executive function, memory, speech, visual constructional skills, abstract thinking, counting, and orientation (21 points on the MoCA scale versus 28–30 points for normal). We found that the pathogenetic factors of cognitive dysfunction included insufficient antioxidant protection, decreased TNF-α and elevated interleukin-18 levels along with an increased level of C-reactive protein in plasma, which manifested as activation of free-radical oxidation processes and reduced antioxidant system and performance of nonspecific resistance. Perioperative use of the combination antioxidant drug and methylethylpyridinol antioxidants reduced the frequency and severity of postoperative cognitive impairment in patients after laparoscopic cholecystectomy. Conclusion. The most important pathogenetic factors of cognitive dysfunction after laparoscopic cholecystectomy include activation of free-radical oxidation, reduction of antioxidant defense system performance and lack of nonspecific resistance factors. Adding the combination antioxidant drug or methylethylpyridinol to the standard therapy reduces the intensity of radical oxygen species generation, maintains the antioxidant potential, activates production and secretion of nonspecific resistance factors, preventing the development and reducing the severity of cognitive disorders in the perioperative period. Neuropsychological testing and stabilographic examination allow identifying the risk of cognitive disorders in patients after laparoscopic cholecystectomy and provide a rationale for the use of antioxidant therapy for their prevention.

Effect of gliprolines on lipid peroxidation rate in male rats’ immunocompetent organs under conditions of information stress

Introduction. The study of various aspects of the stress-reactivity of the body’s immune system, along with the search for correction tools characterized by immunoregulatory properties, is one of the most relevant areas of physiology and pharmacology. Currently, neuropeptides belonging to the group of glурrоlins (the registered drug “sеlаnk” and the new compounds Рro-Glу-Рro-Leu and Рro-Glу-Рro) are of particular interest in practical application as promising bioregulators, in particular their effects on the processes of free radical oxidation, as well as the ability to restore changes from the immune system, including those formed in response to stress.The aim of the study: was to study the effect of glурrоlins on the intensity of lipid peroxidation, catalase activity in the spleen and thymus of male rats under experimental information stress.Material and methods. The study was performed on white nonlinear male rats on which the model of information stress, based on the formation of behavior in animals in a multi-alternative food-producing maze, was reproduced for 20 days. The initial content of malondialdehyde, the rate of spontaneous and ascorbate-dependent lipid peroxidation were determined by standard spectrophotometric methods, and the activity of catalase in the homogenate of the thymus and spleen of experimental animals was evaluated.Results. Under the studied stress conditions, an increase in peroxidation processes was noted. Against the background of the introduction of sеlаnk, Рro-Glу-Рro and Рro-Glу-Рro-Leu, the suppression of the intensity of lipid peroxidation processes in the homogenates of the spleen and thymus tissue of male rats was established (a decrease in the initial level, the rate of spontaneous and ascorbate-dependent lipid peroxidation).Conclusions. Injection of neuropeptides belonging to the group of glyprolins (sеlаnk, Рro-Glу-Рro-Leu and Рro-Glу-Рro) under informational stress conditions contributes to the suppression of the intensity of lipid peroxidation processes, which indicates the stress-protective and immunocorrective effect of the studied substances.

CHANGES IN PROTEIN AND LIPID PEROXIDATION IN ORGANS OF HEPATOPANCREATOBILIARY SYSTEM, ENZYMATIC ANTIOXIDANTS IN RATS UNDER THE CONDITIONS OF DIETS WITH EXCESSIVE CARBOHYDRATES OR FATS

Among the mechanisms of pathological processes development, in particular obesity, an important role belongs to the increase in the intensity of oxygen-dependent processes. It is known that the products of protein and lipid peroxidation can change the structure of the cell membrane, lead to denaturation of proteins and damage to amino acids. Accumulation of protein and lipid peroxidation products can inhibit oxidative phosphorylation and glycolysis, can cause tissue edema and worsen the course of inflammatory processes. Such changes may occur against the background of inertia or suppression of antioxidant reserves. The in-depth study of the obesity development against the background of high-carbohydrate or high-fat diets attracts attention.&#x0D; The aim of the research was to study the peculiarities of indices of the oxygen-dependent processes and anti-radical protection of the body against the background of a high-calorie diet during the experiment. The study was performed using mature male rats on a diet with excessive amount of carbohydrates (experimental group 1) and fats (experimental group 2) and on a standard diet of vivarium (control group).&#x0D; As a result of the study in the blood serum of experimental rats there was observed an increased content of products of the oxidative modification of proteins in the blood serum at 64.35% – 3.3-fold (p˂0.05), in liver tissues – 2.6-4.5-fold (p˂0.01) and pancreas at 67.86% – 5.6-fold (p˂0.05) regarding the control group data. Changes in lipoperoxidation indices were unidirectional. In particular, in the blood serum of animals on high-carbohydrate and high-fat diets there was an increase in the content of diene conjugates (DC) and products that react to thiobarbituric acid (TBA-AP) at 72.37% – 2.2-fold (p˂0.001), in the tissues of liver and pancreas – an increase in the level of TBA-AP at 44.07% – 6.0-fold (p˂0.01), respectively regarding the control. There were no significant differences found between the studied indices of protein and lipid peroxidation in animals of the experimental groups 1 and 2. The resulting changes may indicate a number of abnormalities (structural rearrangement of hepatocyte membranes, impaired cellular metabolism and energy metabolism, increased unsaturated fatty acids), which in turn can lead to the development of diabetes mellitus and obesity.&#x0D; Activation of protein and lipid peroxidation occurred under the conditions of increased catalase activity at 2.5-3.4-fold (p˂0.05), ceruloplasmin content at 54,61-88,65% (р˂0,05), iron transferrin saturation at 43,58-51,28% (р˂0,01) against the background of reduced superoxide dismutase and glutathione reductase activity (at 26,84-83,34% р˂0,01) regarding the values in intact animals. The determined changes of antioxidant reserve did not depend on the diet type. Such changes may indicate a corresponding strain on the functional abilities of the antioxidant system during the increase in the intensity of oxidative stress under the conditions of obesity.&#x0D; The resulting disorders reflect the development of oxidative stress and are the risk factors for structural adjustments and functional changes in the hepatopancreatobiliary system organs. Activation of the processes of free radical oxidation of proteins and lipids against the background of inhibition of antioxidant enzymes can play a significant role in the development of obesity complications, especially such as hypertension, atherosclerosis, heart failure, type 2 diabetes mellitus.

Biotic and abiotic degradation of suspended particulate lipids along a transect in the Chukchi Sea

Lipids and their degradation products were investigated in samples of suspended particulate matter (SPM) collected in summer 2015 from surface waters of a South-North transect (ca. 65–81°N) of the Chukchi Sea. This material appeared to be composed mainly of diatoms (dominated by Thalassiosirales) and copepod faecal pellet debris. The high solar irradiances measured in the surface waters (up to 500 W m−2) favour chlorophyll (sensitizer) photobleaching at the expense of Type II photosensitized oxidation of unsaturated lipid components of phyto- and zooplankton (photodynamic effect). The weak photoreactivity of wax esters of herbivorous zooplankton in these SPM samples contrasts with previous observations of strong photooxidation of these compounds in sinking particles, which suggests that the photodynamic effect should be favoured in large faecal pellets of herbivorous copepods sinking quickly in weakly irradiated zones. Autoxidation (free radical induced oxidation) processes operating in all oxic environments appeared to be particularly efficient in faecal pellets of omnivorous and carnivorous zooplankton and limited in those of herbivorous origin. These differences were attributed to the consumption of algal antioxidants (such as mycosporine-like amino acids and carotenoids) during the diet of omnivorous and carnivorous copepods, favouring the involvement of free radical oxidation processes.

Effects of melatonin and metformin in preventing lysosome-induced autophagy and oxidative stress in rat models of carcinogenesis and the impact of high-fat diet

Imbalanced glucose tolerance and insulin resistance remain important as high cancer risk factors. Metformin administration to diabetic patients may be associated with a reduced risk of malignancy. The combined effects of the hormone melatonin and metformin in oncology practice have shown positive results. The relevance of our study is to find out the role of specific biomarkers of lysosome destruction and oxidative stress data in carcinogenesis models. The present study was designed to investigate the comparative synergic effect of peroral antidiabetic metformin (MF) and pineal hormone melatonin (MEL) administered alone and in combination in two different rat’s models of mammary tumour proliferation in vivo (N-methyl-N-nitrosourea, NMU or 7,12-dimethylbenz[a]anthracene, DMBA). We have studied the processes of lysosomal destruction (alanyl aminopeptidase AAP, leucyl aminopeptidase LAP, acid phosphatase AcP, β-N-acetylglucosaminidase NAG, β-galactosidase β-GD and β-glucuronidase β-GR) caused by evaluated oxidative stress in three types of tissues (liver, heart, and spleen) in female Sprague–Dawley rats fed a high-fat diet (10% of total fat: 2.5% from lard and 7.5% from palm olein). Our results revealed an increase in the activity of the studied lysosomal enzymes and their expression in a tissue-specific manner depending on the type of chemical agent (NMU or DMBA). MANOVA tests in our study confirmed the influence of the three main factors, type of tissue, chemical impact, and chemopreventive agents, and the combinations of these factors on the lysosomal activity induced during the process of cancerogenesis. The development and induction of the carcinogenesis process in the different rat models with the high-fat diet impact were also accompanied by initiation of free-radical oxidation processes, which we studied at the initial (estimated by the level of diene conjugates) and final (TBARS products) stages of this process. The combined effects of MEL and MF for the two models of carcinogenesis at high-fat diet impact for AAP, LAP, and AcP showed a significant synergistic effect when they impact together when compared with the effects of one substance alone (either MEL or MF) in the breast cancer model experiments. Synergistic effects of limiting destructive processes of lysosomal functioning β-GD enzyme activity we obtained in experiments with MEL and MF chemoprevention for both models of carcinogenesis for three tissues. The statistical SS test allowed us to draw the following conclusions on the role of each lysosomal parameter analyzed as an integral model: NAG > AcP > β-GD > β-GR > AAP > LAP.

Стан прооксидантно-антиоксидантної регуляції у хворих на серозні менінгіти

Актуальність. Серозні менінгіти займають провідне місце серед уражень центральної нервової системи, питома вага яких у структурі нейроінфекцій коливається від 25 до 70 %. Дисбаланс у функціонуванні прооксидантно-антиоксидантної системи відіграє провідну роль у пошкодженні нервових клітин та призводить до їх загибелі. Мета дослідження: дослідити показники прооксидантно-антиоксидантної регуляції в динаміці захворювання у хворих на серозні менінгіти. Матеріали і методи. Під спостереженням перебували 64 хворі на серозні менінгіти віком від 18 до 74 років. Спектрофотометричним методом визначали вміст у сироватці крові хворих на серозні менінгіти стабільних метаболітів оксиду азоту — нітритів, показників спонтанної та метал-каталізованої окисної модифікації білка, а також активність каталази. Контрольну групи становили 30 здорових осіб. Результати. У хворих на серозні менінгіти при госпіталізації на тлі домінування клінічних ознак загальноінтоксикаційного, загальномозкового, менінгеального синдромів виявлено підвищення (р &lt; 0,0001) показників спонтанної та метал-каталізованої окисної модифікації білка, вмісту нітритів у поєднанні з низькою (р &lt; 0,0001) активністю каталази у сироватці крові порівняно зі здоровими людьми. На початку другого тижня загальноприйнятого лікування певне регресування клінічної симптоматики у хворих на серозні менінгіти супроводжувалось поглибленням дисбалансу показників прооксидантно-антиоксидантної регуляції в бік процесів вільнорадикального окислення, який залишався й на момент виписки хворих зі стаціонару. Висновки. У хворих на серозні менінгіти при госпіталізації виявлено дисбаланс показників прооксидантно-антиоксидантної регуляції, який поглиблювався на другому тижні загальноприйнятого лікування та залишався на момент виписки хворих зі стаціонару.

Stepwise Cerebral Ischemia Causes Disturbances in Mitochondrial Respiration of Neurons in the Cerebral Cortex of Rats

Objectives: To conduct a comparative analysis of respiration of mitochondria of brain homogenates of rats with stepwise subtotal cerebral ischemia with different duration between ligations of both common carotid arteries. Methods: The experiments were performed on 24 male mongrel white rats weighing 260 ±20 g. Cerebral ischemia (CI) was simulated under intravenous thiopental anesthesia (40-50 mg/kg). The control group consisted of falsely operated rats of similar sex and weight. To study mitochondrial respiration, the brain was extracted in the cold (0-4°C), dried with filter paper, weighed and homogenized in an isolation medium containing 0.32 M sucrose, 10 mM Tris-HCl, 1 mM EDTA, pH 7.4 (in a ratio of 1:10), using Potter-Evelheim homogenizer with Teflon pestle according to the modified method. To prevent systematic measurement errors, brain samples from the compared control and experimental groups of animals were studied under the same conditions. Results: Stepwise SCI with an interval of 1 and 3 days between bandages of both OCA leads to damage to the neurons of the parietal cortex and hippocampus of rats, which manifests itself in a decrease in their size, deformation of the pericaryons, an increase in the number of shrunken neurons and shadow cells. The most pronounced changes were observed in the subgroup with an interval between dressings of 1 day. These changes were similar to the changes in SCI (p&gt;0.05), except for the absence of cells with pericellular edema in the hippocampus and a smaller number of them in the parietal cortex. SCI with an interval between WASP dressings of 7 days, on the contrary, it is manifested by less pronounced histological changes, especially in the hippocampus. Conclusion: In cerebral ischemia, damage to the inner mitochondrial membrane occurs due to activation of free radical oxidation processes. Damage to the inner mitochondrial membrane, in turn, leads to an increase in its permeability and a decrease in the level of the proton gradient due to the transition of protons along the concentration gradient through the resulting nonspecific pores into the mitochondrial matrix. As a result, the efficiency of ATP synthesis decreases, and more substrates and oxygen are required to maintain the intermembrane potential under these conditions.

Intensity of local processes of free radical oxidation in red lichen planus of the oral mucosa

Intensity of local processes of free radical oxidation in red lichen planus of the oral mucosa

Features of ozone effect on the oxygen-dependent blood processes under hypercapnia conditions

The aim of this work is to study of ozone effect on blood oxygen-dependent processes under hypercapnia conditions. The studied blood samples are pretreated with a hypercapnic gas mixture followed by the addition of ozonized isotonic sodium chloride solution (with an ozone concentration of 6 mg/l), as well as gaseous transmitters donors, nitroglycerin and sodium hydrosulfide. It has been established that hypercapnia enhanced the ozone effect on the blood oxygen transport function and was characterized by the oxyhemoglobin dissociation curve shift to the right, also increased hydrogen sulfide synthesis and absence of changes in the nitrates/nitrites concentration. Under these conditions nitroglycerin and sodium hydrosulfide did not change the parameters of the blood gas transport function, but increased the level of nitrate/nitrite and hydrogen sulfide. Preliminary hypercapnia does not eliminate the activating effect of ozone on the free radical oxidation processes, and the addition of the applied gaseous transmitter donors does not contribute to the regulation of the studied parameters.

РЕГУЛЯЦИЯ АНТИОКСИДАНТНОЙ СИСТЕМЫ РЫБ БИОЛОГИЧЕСКИ АКТИВНЫМИ КОРМОВЫМИ ДОБАВКАМИ

The article contains results of the research on the influence of "Sporothermin" probiotics and "Chiktonik" vitamin-amino acid complex on the processes of free-radical oxidation of lipids in the muscle tissue of fish. Three groups of sexually mature African catfish were formed. The first test group received "Sporothermin" probiotic at a dose of 2 g / kg of feed. The second group received "Chiktonik" vitamin-amino acid complex at a dose of 2 ml / kg of feed, the third group was the control and received only LimKorm "Som" brand feeds. All groups were tested for malondialdehyde content (MDA) in three months. In the control group, the content of MDA of males was 7948.71 mmol / 100 g of tissue, females - 8119.65 mmol / 100 g of tissue. Fish reared with the probiotics had the lowest levels of lipid peroxidation. Males had the MDA level of 3931.62 mmol / 100 g of tissue, and females - 4273.5 mmol / 100 g of tissue. As for the second group, which received “Chiktonik” vitamin-amino acid complex, the MDA content was lower than in the control, but higher than in the group which received the probiotics and was 4358.97 mmol / 100 g of tissue (males), and 4957.26 mmol / 100 g of tissue (females). It can be concluded that the usage of "Sporothermin" probiotics and "Chiktonik" vitamin-amino acid complex in the diet of African sharptooth catfish leads to a decrease of free radical processes, reduces the activity of lipid peroxidation, stimulates the antioxidant system, provides resistance to oxidative stress, revitalizing and increasing the vitality of the organism fish.

The state of pro- and antioxidant systems in rats with DMH-induced colon carcinogenesis on the background of extracorporeal detoxification

Aim: Cancer is one of the leading causes of death in the world. The aim of this research was to study the indices of pro- and antioxidant systems in rats with dimethylhydrazine (DMH)-induced colon carcinogenesis on the background of the enterosorbent AUT-M use. Materials and methods: The study was performed on 70 white male rats weighing 200–250 g. Adenocarcinoma of the colon was simulated by subcutaneous injection of the DMH (Sigma-Aldrich Chemie, Japan) at a dose of 7.2 mg/kg once a week during 7 months. Enterosorbent AUT-M was administered intragastrically daily for 21 days after simulation of carcinogenesis at a dose of 1 ml of suspension per 100 g of animal body weight. The state of the pro- and antioxidant systems was studied by the content of oxidative modification of proteins products (OMP), the activity of superoxide dismutase (SOD), catalase (CAT), contents of ceruloplasmin (CP) and reduced glutathione (GSH). Results: It was found that DMH-induced colon carcinogenesis in rats is accompanied by disorders in the antioxidant defense system and activation of free radical oxidation processes. Enterosorbent AUT-M provides a significant reduction in the content of OMP370 and OMP430 in both blood serum and liver homogenate of rats. Moreover, the use of enterosorbent AUT-M demonstrated a significant increase in the activity of SOD, CAT, content of GSH and a decrease in CP content in investigated tissues. Conclusion: The use of enterosorbent AUT-М demonstrated prominent potential suppression for oxidative stress and positive effect on antioxidant defense system in rats with DMH-induced colon carcinogenesis.

Rhaponticum uniflorum and Serratula centauroides Extracts Attenuate Emotional Injury in Acute and Chronic Emotional Stress.

In modern life, the use of plant stress-protectors has taken on particular significance due to the wide distribution of neurosis-like and neurotic diseases caused by neuroendocrine-immune system imbalance. Special attention has been paid to the plants containing ecdysteroids, i.e., hormone-like bioactive substances with high adaptogenic activity. The article deals with the study of bioactivity of two plant extracts as Rhaponticum uniflorum (L.) DC. and Serratula centauroides L. with a high content of ecdysteroids and phenolic compounds. The models of acute and chronic emotional stress in white rats were used to estimate the stress-protective activity of R. uniflorum and S. centauroides extracts. Both extracts showed the stress-protective effect via inhibiting the development of signs induced by single and long-term effects of stress factors. In acute stress, the development of Selye's triad signs was less pronounced against the background of the plant remedies introduction. In chronic stress, the extracts prevented the development of anxiety-depressive syndrome. Besides, R. uniflorum and S. centauroides extracts banned the development of stress-induced injuries in the brain cortex and had a neuroprotective effect on ischemia against chronic stress. The stress-protective effects of both plant extracts were based on a decrease of hyperactivation of the central stress-promoting systems (sympathoadrenal, hypothalamic-pituitary-adrenal) due to their GABA-mimetic effects. Peripheral mechanisms were connected with the inhibition of free radical oxidation processes and with an increase in the endogenous antioxidant system activity. Thus, R. uniflorum and S. centauroides extracts have a high potential to increase non-specific body resistance against acute and chronic emotional stress effects.