Tissues Of Experimental Animals Research Articles

DYNAMIC CHANGES IN HISTOLOGICAL AND MORPHOMETRIC INDICATORS OF THE LUNGS IN SEXUALLY IMMATURE RATS DURING SIMULATION OF PARTIAL TRACHEAL STENOSIS

Introduction. The morphological features of the respiratory system in laryngomalacia remain insufficiently understood, particularly regarding structural, cytological, and functional alterations. The aim of this study is to investigate the morphological characteristics of the respiratory compartment in the lungs of sexually immature rats, conduct a morphometric assessment of lung tissue density, analyze the dynamics of erythrocyte mass and collagen accumulation, and identify correlations between these parameters. Materials and Methods: The study involved sexually immature male Wistar rats aged 25-28 days and weighing 40-55 g. Partial tracheal stenosis was induced in experimental animals using a developed method, restricting the tracheal lumen by 20-25%. The stenosis was maintained for 7 and 21 days in different groups. In one group, tracheal stenosis was relieved after 7 days by removing the compressive ligature. Histological, histochemical, and morphometric methods were employed to study changes in lung tissue. Results. Pathological changes in lung tissue during hypoxia were characterized by an increase in the number of different types of cells and erythrocyte mass, especially on the 21st day of the experiment and the removal of ligatures from the trachea in experimental animals. Disturbances in the microcirculation of the lung acini were manifested by a sharp increase in blood filling of the microvessels and expansion of their lumen. In this case, the process of erythrocyte penetration into the lumen of the alveoli was sometimes noted. The results of histochemical detection of collagen indicate that in the lung tissue of experimental animals there is no activation of fibrogenetic processes, which would be accompanied by a simultaneous increase in the specific density of collagen. Indicators characterizing the lung tissue (number of cells, their specific density) made it possible to evaluate the corresponding correlations. At the same time, they were not associated with the level of collagen or erythrocyte density in the studied loci of the respiratory system of experimental sexually immature rats. A significant increase in the specific density of erythrocyte mass in lung tissue did not depend on the duration of the experiment. Removal of the ligature and restoration of the tracheal lumen did not significantly affect the restoration of alveolar acini and the spectrum of identified cells. In addition, an increase in the specific density of lung tissue was observed. Conclusion. The findings of this study contribute to deeper understanding of lung damage in children with laryngomalacia and associated respiratory system ventilation impairment. The observed reactive changes in lung connective tissue and collagen synthesis during hypoxia do not necessarily indicate the development of respiratory system fibrosis. However, longer exposure to hypoxic conditions may increase the risk of fibrosis in children.

Liquid respiratory desaturation. The first experience of application on large biological objects

Introduction. This article is a continuation of the publication of the experimental studies results of prevention of acute decompression sickness (aDCS) in laboratory animals by the method of liquid respiratory desaturation (LRDS). LRDS is a method of preventing decompression disorders by the excretion of metabolically indifferent gases (in particular nitrogen) from the body during spontaneous respiration with liquid or artificial liquid lung ventilation (ALLV), by dissolved gas concentration gradient "from tissues to respiratory fluid". The method allows to provide rapid desaturation of the body from metabolically indifferent gases in the process of liquid respiration before and/or during decompression, thereby creating conditions for application of ultra-fast decompression profiles without the risk of decompression disorders.
 The aim of the study was to confirm the possibility of LRDS being a method of DCS prevention on large laboratory animals (minipigs).
 Materials and methods. The studies were performed on Wiessenau minipigs (n=8) — male and female, aged 4–5.5 months and weighing 7.1–11.2 kg. Animals of the control (n=4) and experimental (n=4) groups were subjected by compression by keeping in an air environment under high pressure (absolute 0.5 MPa for 60 minutes) to saturate tissues with indifferent gas (nitrogen). After compression experimental group was exposed to 30-minute ALLV with a liquid (perfluorodecalin) saturated with an oxygen under normobaric conditions. Air environment pressure during procedure of artificial lung ventilation was kept at 0.5 MPa. Decompression of the control and experimental groups was carried out in non-stop manner for 80 and 40 seconds respectively. The investigation of severity of clinical manifestations of DCS (changes in hemodynamic and respiratory parameters) including ultrasonic examination of gas bubbles in the heart and large vessels of the liver and as well as survival of animals in groups and pathoanatomical changes was performed.
 Results of the study. Clinical manifestations, ultrasonic scanning of the heart and venous vessels of the liver, as well as morphological examination data indicated the development of severe acute post-decompression disorders (PDD) in animals of the control group, which caused deaths in 100% of cases. Meanwhile all animals in experimental group survived and their state was stable. According to ultrasonic examination, the presence of small number of gas bubbles in the right-side heart chambers and liver's venous vessels being noted, but they disappeared after several hours. Deviations of the respiration's parameters function from background values (shortness of breath of a mixed type with the participation of auxiliary muscles, etc.) observed from the 2nd to the 4th day after ALLV, as well as compensatory reactions from the cardiovascular system (heart rate variability and instability of hemodynamic parameters) were caused by ALLV.
 Conclusions. Compressed air exposure 0.5 MPa for 60 minutes followed by 80 seconds of non-stop decompression allows to provoke the severe acute PDD minipigs model, manifested by pronounced intravascular gas formation, the development of acute respiratory and cardiovascular insufficiency causing the development of adverse outcomes.
 The ultrasound method of visual assessment of intravascular gas formation severity, adapted for minipigs, together with the dynamics of changes in the indicators of respiratory and cardiovascular systems makes possible to assess not only state of animal under anesthesia, but also the effectiveness of PDD prevention measures.
 The usage of ALLV with PFC liquid completely saturated with 100% oxygen under normobaric conditions makes possible partial removal of indifferent gas (nitrogen) dissolved in tissues of experimental animals during exposition in a compressed air environment before decompression and thereby carry out the prevention of DCS by LRDS method. It makes possible to implement successfully ultra-fast decompression profiles, incompatible with life in the control group.
 The state of animals from experimental group after LRDS is characterized by lung impairment caused by ALLV in hyperbaric conditions accompanied by temporary changes of external respiration function and compensatory reactions of cardiovascular system, observed during first 4 days.
 Ethics. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. The Clinical Study Protocol was approved by local Ethics Committee of The Federal State Budgetary Scientific Institution «Izmerov Research Institute of Occupational Health».

The effect of C60 fullerenes on the recovery of muscle soleus contraction dynamics in rats after chronic alcoholization

Background. It has been shown that the available therapeutic agents do not eliminate the consequences of miotic pathologies in chronic alcoholism, the most significant of which are disturbances in the dynamics of muscle contraction. A positive effect of biocompatible water-soluble C60 fullerenes on the contraction parameters of damaged muscles has been established. In addition, administration of C60 fullerene aqueous solution during chronic alcoholization of rats protects muscle tissue from damage caused by oxidative stress. Materials and Methods. Biomechanical parameters such as the values of the minimum and maximum contraction force and the muscle force impulse were evaluated using tensometry. The blood levels of creatine phosphokinase and lactate dehydrogenase, creatinine and lactate as well as the level of oxidative processes in muscle tissue of experimental animals (content of hydrogen peroxide, activity of catalase, glutathione peroxidase and superoxide dismutase) as markers of muscle damage were determined using methods of biochemical analysis. Results. The C60 fullerene aqueous solution effect on the skeletal muscle contraction dynamics in rats after chronic alcoholization for 9 months and cessation of alcohol consumption for 1 month was investigated. It was established that water-soluble C60 fullerenes (daily dose of 1 mg/kg) reduce the effects of chronic alcoholization by 35–40±2 % on the studied biomechanical parameters and by 20±1 % on the studied biochemical parameters compared to the group of alcoholized animals, thus increasing the energy capabilities of the muscular system. Conclusions. The obtained data indicate a pronounced protective effect of C60 fullerenes on the muscle soleus contraction dynamics during the development of alcoholic myopathy, which opens up the potential possibility of their use for the prevention and correction of miotic damage.

Dynamics of changes in the content of proteoglycans in the tissues of the cerebellum of rats under the influence of hypokinesia

The article reflects the dynamics of changes in the content of proteoglycans in preparations that were taken from the cerebellum of experimental animals after modeling hypokinesia. Laboratory animals were removed from the experiment at different time intervals (3, 7, 14, 21 and 30 days of simulated hypokinesia) to identify the dynamics of changes in proteoglycan content using histochemical studies. The experiment was carried out on laboratory rats of the Vistar breed. The animals were divided into two groups: control and experimental. All laboratory rats were kept under standard vivarium conditions. The experiment is based on the model of hypokinesia proposed by E. A. Kovalenko. Complex studies showed the dynamics of changes in the content of proteoglycans, which were not homogeneous at different stages of the experiment. However, despite the different trends in the dynamics of the content of various fractional components of proteoglycans, one can note a general trend towards a decrease in proteoglycans. This indicates a negative effect of hypokinesia on the productive function of cerebellar tissue in experimental animals.

Dynamics of changes in cadmium levels in environmental objects and its impact on the bio-elemental composition of living organisms.

As a result of intensive anthropogenic impact in the biosphere there is a rapid process of accumulation of heavy metal salts. They have led to the aggravation of problems associated with the pollution of ecosystems and basic food products of plant and animal origin. Environmental pollution by these compounds is caused by their persistence in environmental objects, migration ability, accumulation by plants. This contributes to their accumulation in the human environment. A number of studies have shown that heavy metals have mutagenic, toxic effects and affect the intensity of biochemical processes. Therefore, the presence of heavy metals in the environment is extremely undesirable. Moreover, the ecological state of the environment is directly related to changes in the human internal environment. Deficiency or excess of certain bioelements in soils and drinking water or non-compliance with its stable chemical composition causes the development of dysmicroelementosis. The ecological situation of the Carpathian region is closely related to the state of soils and water resources. In this regard, it is advisable to study and control the level of cadmium compounds in the environment of the region. The study of the effect of cadmium intoxication on the macro- and microelement composition of the brain and myocardium of experimental animals is also worthwhile. Materials and methods. Soils and drinking water of the plain, foothill and mountainous zones of the region, as well as organs and tissues of experimental animals served as the object of research. Cadmium levels in drinking water and myocardial tissues and brain of experimental animals have been measured by atomic absorption spectroscopy. Results and discussion. The study of soils in the Prykarpattia region has revealed an increase in the toxic element cadmium. Its content is 1.1-1.5 times higher than background levels. The analysis of drinking water allowed to establish that a significant number of people living in the plain and foothill zone of the region consume water with a high content of cadmium. The main stages of cadmium intake and accumulation in plants have been analyzed. Significant disorders in the body of experimental animals under conditions of excessive intake of cadmium compounds have been revealed. It was accompanied by the accumulation of cadmium in the myocardium and brain, on the background of redistribution of vital macronutrients calcium and magnesium along with micronutrients copper and zinc. Thus, excessive intake of cadmium salts causes the development of dysmicroelementosis, which is accompanied by a violation of the homeostasis of a living organism. It is suggested to conduct continuous monitoring of the level of toxicants in the ecosystem as an integral component of environmental monitoring.

HBO aftereffect on lipid peroxidation and enzyme antioxidants of the brain: prospective experiental study

OBJECTIVE. Study the effect of a single and multiple administration of hyperbaric oxygenation (HBO) in the therapeutic regime on the processes of lipid peroxidation (LPO) and enzyme of antioxidative defense in phylogenetically various structures of the brain in the period of the immediate and remote aftereffect of expositions.
 MATERIALS AND METHODS. Experiments were carried out on 87 nonlinear white male rats weighing 180-230 grams. Hyperbaric oxygenation was conducted by medical oxygen in the experimental pressure chamber in the “mild” mode (2 ata, 50 min isopression), 1 session per day in the morning. The study was carried out after 1, 5, 10 sessions, in 5 and 10 days after 1 session and in 5 days after 5 sessions of HBO. The content of malondialdehyde (MDA) was determined in the brain stem, cerebellum and large brain hemispheres. The state of an enzyme element of antioxidant defense was evaluated by superoxide dismutase (SOD) and catalase.
 RESULTS. It was found that exposure to oxygen under high pressure caused increased intensity of LPO processes in the brain that progresses from 1 to 5 sessions. While MDA changes in the brain stem were detected later than in the hemispheres and cerebellum. LPO intensification in the brain proceeded against the background of increased activity of SOD. After 10 sessions of HBO LPO intensity decreased that was confirmed by reduced MDA content and SOD activity in examined brain tissue. Catalase activity reduced in the stem after 5 sessions and increased in the cerebellum and hemispheres after 10 sessions of HBO. Aftereffect of 1 HBO session was characterized by persistent increase in MDA concentration in the brain regions, detected in 5 and 10 days after exposure and was accompanied by increased SOD activity against the background of reduced catalase activity. In 5 days after 5 sessions the increase in MDA content and SOD activation was observed only in the tissue of the cerebral hemispheres.
 DISCUSSION. The use of HBO in the mode 2 ata, 50 min stimulates reactions of free radical oxidation (FRO) in the brain. The dynamics of their development with continued exposure shows that there are enough resources of the brain antioxidant defense to compensate hyperoxic load, including 10-fold exposure and no depletion of the reserves of enzyme antioxidant element in the brain is observed. After a single exposure of hyperbaric oxygen FRO activation remains during 10 days that can be concluded from an increased level of MDA and an increased activity of SOD in all the brain regions against the background of reduced catalase activity of stem structures and cerebellum. Repeated 5-fold exposures have a shorter metabolic “footprint”: in 5 days LPO effect and SOD activation are less pronounced than in the period of 1 session aftereffect both in 5 and 10 days.
 CONCLUSION. The therapeutic “mild” mode of HBO (2 ata, 50 min, 1 session per day) causes FRO activation in the brain tissue of experimental animals. Its intensity is controlled by the activation of enzyme protection mechanisms that is enough to compensate FRO changes with this mode of hyperoxic load. After ending exposures more pronounced aftereffect of HBO in the brain regions is found after 1 session compared to 5 sessions.

Specificities of accumulation of essential polyunsaturated fatty acids of ω-3 and ω-6 families in the tissues of bulls after supplementing their diet with the sources of fatty acids and mineral elements

Aim. To determine the intensity of growth of fattening bulls and the specificities of the accumulation of essential polyunsaturated fatty acids from the ω-3 and ω-6 families in their tissues after supplementing their diet with the sources of essential fatty acids and copper sulfate to increase their meat productivity and improve the biological value of beef. Methods. The study was conducted using the methodological approaches, common for international practice in accordance with the requirements of ISO 17025, and using the conventional methods of peer groups involving clinically healthy animals. The content of polyunsaturated fatty acids of the ω-3 and ω-6 families was determined by gas chro- matography using the Chrom-5 device. Copper content was determined by the method of atomic absorption spectro- photometry using the Selmi C-115 M1 device. Results. It was found that the introduction of linseed oil (as a source of α-linolenic acid, which is a precursor of polyunsaturated fatty acids of the ω-3 family) and sunflower oil (as a source of linoleic acid, which is a precursor of polyunsaturated fatty acids of the ω-6 family), the synthetic substance doxane (as an inhibitor of biohydrogenation processes in unsaturated fatty acids in the rumen) and pentahydrate copper sulfate (as a source of copper) to the diet of young fattening cattle caused a probable increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 family and copper in their liver and skeletal muscles. At the same time, the increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 families and copper in the abovementioned tissues due to the stimulation of metabolic processes in the body contributed to a probable increase in the average daily weight gain of young fattening animals. Thus, there was a direct relationship between the content of α-linolenic and linoleic acids and copper in the diet and their content in the tissues of experimental animals, productivity characteristics, and biological value of beef. Conclusions. The introduction of a mixture of linseed and sunflower oils into the diet of fattening bulls led to an increase in the content of α-linolenic and linoleic acids and a 1.7-fold decrease in the ratio between essential polyunsaturated fatty acids of the ω-6 family and that of the ω-3 family. The increase in the content of copper and essential polyunsaturated fatty acids of the ω-6 and ω-3 families in the diet of fattening bulls led to their accumulation in the liver and skeletal muscles, which contributed to the enhanced biological value of beef.

Multiple Influence of Vibration on Biochemical Brain Indicators

Dysfunction of the nervous system is one of the main manifestations caused by vibration. With repeated exposure to vibration, significant changes in the activity of enzymes and the content of the studied substrates in the brain tissue of experimental animals are observed. The observed changes in the activity of enzymes and the content of the studied substrates of brain tissue and the associated disturbances in the basic biochemical metabolic processes may be the direct cause of serious disorders of the functions of the nervous system. According to research results, it was revealed that exposure to general vibration leads to disturbances in the process of transamination of alanine-, aspartic-amino acids, cholinesterase, the activity of enzymes of the tricarboxylic acid cycle (GDH, SDH and MDH), alkaline phosphatase, ribonuclease and lactate dehydrogenase, as well as the content of total protein, serotonin, histamine and acetylcholine in the brain of experimental animals.

Correlation Analysis of Galectin-3 Serum Level in Obesity with and without Obesity

There are more than 3.4 million deaths every year in the world due to overweight and obesity. Obesity is a chronic proinflammatory condition marked by increased lipid and adipose tissues, leading to ectopic fat accumulation with increased levels of proinflammatory cytokines. Obesity causes a progressive increase in galectin-3 expression, especially in visceral and subcutaneous adipose tissue in experimental animals. Galectin-3 is upregulated in obesity and is defined as a proinflammatory molecule that can cause insulin resistance. This study aims to analyze differences in galectin-3 levels between obese and non-obese subjects. This was a cross-sectional study, using a total of 80 subjects. The study was conducted throughout August 2022. The samples were grouped into obese and non-obese based on Body Mass Index (BMI). The galectin-3 measurement used the Enzyme-Linked Immunosorbent Assay (ELISA) method. Statistical tests used the Mann-Whitney test and Spearmen rho; the test results were significant if the p-value <0.05. The samples were divided into obese and non-obese groups, each group had 40 people. Galectin-3 levels in the obese group were 0.9±0.36 ng/mL significantly higher than the non-obese group’s 0.43±0.11 ng/mL, (p<0.001). There was a strong positive correlation between levels of galectin-3 and BMI, (r=0.866, p<0.001). There is a positive correlation between serum galectin-3 levels and BMI. The greater value of the BMI, the higher levels of galectin-3.

Стан глутатіонової системи головного мозку щурів за умов споживання енергетичного напою

The paper presents the results of studies of the energy drink influence on the state of the glutathione system of the rat brain. Energy tonics belong to a group of drinks containing a large number of active components that are able to stimulate the central nervous system of a person and to increase physical performance, as well as to affect circadian rhythms, extending the period of wakefulness. Literary sources also indicate the negative impact of energy drinks on certain functional systems of the human body. The study was carried out on white rats of the Wistar line weighing 180–200 g, which were on a standard vivarium diet under regulated microclimate parameters (humidity, lighting and temperature regime). All experiments on animals were conducted in compliance with the requirements of the European Convention for the Protection of Vertebrate Animals Used for Experimental and Scientific Purposes (Strasbourg, 1986). A non-inhalation method of anesthesia was used to collect the necessary material, namely intramuscular injection of sodium thiopental at the rate of 60 mg/kg. The experimental animals were divided into 5 groups according to the logical criterion of sample formation: 1st (control group) — rats received drinking water; 2nd — the animals received an energy drink for a month, the material was collected on the 1st day after the end of energy drink consumption; 3rd — animals that received an energy drink for a month, the material was collected on the 10th day after the end of the experiment; 4th — the animals received an energy drink for a month, the material was collected on the 20th day after the end of the experiment; 5th — the rats received an energy drink for a month, the material was collected on the 30th day after the end of the experiment. Determination of the activity of enzymes of the glutathione system (glutathione reductase, glutathione peroxidase and glutathione transferase) and the enzyme of the pentose phosphate pathway (glucose-6-phosphate dehydrogenase) was performed using the enzymatic method. The consumption of an energy drink by experimental groups of animals leads to changes in the activity of enzymes of the glutathione system: an increase in the activity of glutathione reductase in the 2nd, 4th, 5th groups, at the same time as a decrease in the activity of this enzyme in representatives of the 3rd group of animals, the activity of glutathione peroxidase increased in the 4th, 5th and decreased in 2nd and 3rd groups, an increase in glutathione transferase activity was observed in all experimental animals. The activity of the enzyme glucose-6-phosphate dehydrogenase increased in 2.3 and decreased in 4.5 studied groups. The obtained results demonstrated a significant influence of the energy drink on the state of antioxidant protection of the brain tissues of experimental animals, in particular on the state of the glutathione system. The interpretation of enzyme activity indicators proves that energy group drinks can lead to further violations of the ability to maintain the stability of the body’s internal environment.

Anti-TPO-mediated specific features of the placenta immunohistochemical profile and possible mechanisms for fetal loss.

Passive transfer of antithyroid antibodies in mice leads to reproductive disorders. The purpose was to assess the placental tissue of experimental animals under the influence of the circulating thyroperoxidase antibodies. We performed an immunohistochemical examination of murine placentae after a passive transfer of thyroperoxidase antibodies. Placentae of mice that passively transferred IgG from healthy donors were used as control samples. For histological examination, 30 placental samples were selected from mice from the anti-TPO group and 40 placental samples were taken from mice from the IgG group. Immunostaining for VEGFR1, THBS 1, Laminin, CD31, CD34, FGF-β, CD56, CD14, TNF-α, kisspeptin, MCL 1, and Annexin V was performed. There is a significant decrease in the relative area of the expression of VEGFR1 (23.42 ± 0.85 vs. 33.44 ± 0.35, P < 0.01), thrombospondin 1 (31.29 ± 0.83 vs. 34.51 ± 0.75, P < 0.01), CD14 (25.80 ± 0.57 vs. 32.07 ± 0.36, P < .01), CD56 (30.08 ± 0.90 vs. 34.92 ± 0.15, P < 0.01), kisspeptin (25.94 ± 0.47 vs. 31.27 ± 0.57, P < 0.01), MCL 1 (29.24 ± 1.06 vs. 38.57 ± 0.79, P < 0.01) in the labyrinth zone of the placentae of mice from the anti-TPO group compared with control group. A significant increase in the relative expression of laminin and FGF-β was noted in the group of mice to which antibodies to thyroperoxidase were transferred, compared with the control group (36.73 ± 1.38 vs. 29.83 ± 0.94, P < 0.01 and 23.26 ± 0.61 vs. 16.38 ± 1.01, P < 0.01respectively). Our study exposed an imbalance of pro- and anti-angiogenic factors, decreased representation of placental macrophages and NK cells, abnormal trophoblast invasion processes, and insufficient expression of antiapoptotic factors in the placentae of mice in which anti-TPO antibodies were passively transferred.

MICROSCOPIC CHANGES IN RAT’S GINGIVA UNDER CONDITIONS OF EXPERIMENTAL PERIODONTITIS AND THE USE OF MESENCHYMAL STEM CELLS

MICROSCOPIC CHANGES IN RAT’S GINGIVA UNDER CONDITIONS OF EXPERIMENTAL PERIODONTITIS AND THE USE OF MESENCHYMAL STEM CELLS

ЭКСПЕРИМЕНТАЛЬНО-КЛИНИЧЕСКОЕ ОБОСНОВАНИЕ РАЗВИТИЯ МУЖСКО-ГО БЕСПЛОДИЯ ПРИ ВОЗДЕЙСТВИИ СЕРОСОДЕРЖАЩЕГО ГАЗА

Under the influence of natural gas containing hydrogen sulfate, it has been found that the level of malondialdehyde was increased in testicular tissue in experimental animals as well as in ejaculate in men employed in gas and oil industry. It has been established that a considerable decrease in the gen-eral quantity of spermatogenic cells took place by more than 7 times compared with the control group; the number of epididymal spermatozoa in rats was decreased by 70 %, necrosis of spermatogenic epi-thelium took place. Considerable decrease in the diameters of seminal tubules on the background of interstitial tissue proliferation at the expense of small Leydig’s cells was found to take place. Experi-mental and clinical data show the same tendencies by indexes of lipoperoxidation at the level of testis under the influence of analogical stressing factors. Spermatozoid concentration in men was found to be decreased by as many as 10times more than in the control group. The leading defects of spermato-zoa were the neck and tail pathologies.

Study on the effect of periodontitis on renal tissue in atherosclerotic mice

Periodontitis is immune inflammatory disease, atherosclerosis (AS) and chronic kidney disease (CKD) are two common systemic diseases. Periodontitis promotes AS and CKD, and CKD interacts with AS. The objective of this animal study was to evaluate the changes of kidney when periodontitis and atherosclerosis exist separately and the degenerative effects of periodontitis on the kidney in atherosclerotic mice. A total of 40 male Apoe-/- mice were randomly divided into four groups: control (NC), periodontitis (PD), AS and AS with PD (AS + PD). AS was induced by high-fat diet feeding, and PD was induced by injection of Porphyromonas gingivalis-Lipopolysaccharide (P.g-LPS) (endotoxin suspension) into the buccal side of mouse maxillary molars. The right maxilla of mice was scanned with micro-CT to evaluate alveolar bone loss; aortic tissue was stained with HE and Oil-Red O to evaluate arterial plaque formation; serum was collected to detect the changes of blood lipids and serum renal function parameters (blood urea nitrogen [BUN], serum creatinine [Scr]); renal histopathological changes were evaluated by HE staining (glomerular and tubular damage scores), PAS staining (glomerular Mesangial matrix index) and Masson staining (percentage of renal fibrosis area); qRT-PCR and ELISA were used to evaluate the expression of renal inflammatory cytokines (tumor necrosis factor-α, Interleukin-1β, neutrophil surface marker Ly6G). The amount of alveolar bone loss: PD group was significantly higher than NC group (p < .05); AS + PD group was higher than PD group, the difference was not statistically significant. Atherosclerotic plaque formation and serum lipid changes: AS group were significantly worse than NC group (p < .05), and AS + PD group were worse than AS group. The results of the corresponding qualitative and quantitative analyses of kidney tissue in experimental animals gradually deteriorated in the NC group, PD group, AS group and AS + PD group and worsened sequentially. Renal function parameters: the content of BUN in AS group was higher than that in PD group, the difference was not statistically significant; Scr in AS group was significantly higher than that in PD group (p < .05); the contents of BUN and Scr in AS + PD group were higher than those in AS group, the difference was not statistically significant. Glomerular and tubular damage scores: AS group were higher than PD group, the difference was not statistically significant; AS + PD group were significantly higher than AS group (p < .001). The ratio of glomerular mesangial matrix to glomerular area and the percentage of renal fibrosis area: AS group were significantly higher than PD group (p < .001), and AS + PD group were significantly higher than AS group (p < .001). Expression of inflammatory cytokines: AS group was higher than PD group, the difference was not statistically significant; AS + PD group was significantly higher than AS group (p < .05). Both PD and AS can aggravate the inflammatory stress of kidney tissue and cause the damage of kidney tissue, and the inflammatory increase and damage effect of AS is stronger; PD can promote kidney damage of atherosclerotic mice by aggravating the renal inflammation in atherosclerotic mice; renal function parameters were not completely synchronized with the changes of renal inflammation and histopathology in each group of mice; PD can promote AS, periodontal inflammation in mice with AS is more severe, and the special changes of blood lipids in mice with AS are closely related to the above results.

Biochemical mechanisms of the energy-protective action of blockers of slow high-threshold L-type calcium channels

This review discusses information about the structure and function of calcium channels in the plasma membrane and mitochondria of the heart, and pharmacological methods for modulating their conductance. Experimental data are presented that characterize the change in the energy metabolism of cardiomyocytes against the background of the transformation of the conductivity of L-type calcium channels of the cell membrane in a non-invasive model of vibration-mediated (56 sessions of total vertical vibration, with a frequency of 44 Hz and an amplitude of 0.5 mm) hypoxia.&#x0D; It was shown that in animals treated with calcium channel blocker adalat (nifedipine INN) against the background of vibration, the rate of endogenous respiration (Ve), measured by the polarographic method using a closed Clark electrode in native homogenate of rabbit myocardial tissue, remained at the level of intact animals and amounted to 16.3 4.3 ng-O atom/ min mg of protein, amytal sensitivity increased by 39% (p 0.05) compared to the group of vibrated animals, low-natality decreased by 40% (p 0.05). The dynamics of the rate of substrate respiration (Vac and Vglu + mal) in the group with adalat returned to that of intact animals, which indicated the restoration of the physiological predominance of the activity of theNADH CoQ-reductase complex in redox reactions. It was found that the blockade of transport of Ca2+ ions at the level of high-threshold (HVA) voltage-dependent ion channels of the L-type of the cell membrane, normalizing the activity of the I enzyme-substrate complex of the respiratory chain and regulatoryly restraining the hyperactivity of succinate dehydrogenase in zone II of the enzyme-substrate complex, has an energy-protective effect. Adalat prevented a low-energy shift and the development of bioenergetic hypoxia in the myocardial tissue of experimental animals.

Chemo-preventive Activity of Ethanolic Extracts of Newbouldia laevis and Olax subscorpioidea Leaves on Methylnitrosourea–induced Stroma Fibrosis in Breast Tissues of Female Albino Rats

Breast cancer represents the most common neoplastic disease in females, accounting for up to one third of new diagnoses of women’s cancer in certain regions of the world. The chemo-preventive activity of ethanolic extracts of Newbouldia laevis and Olax subscorpioidea leaves on methylnitrosourea (MNU)–induced stroma fibrosis in female albino rats was evaluated. Quantitative and qualitative phytochemical screening was carried out to identify and determine the quantity of bioactive compounds. Haematoxylin and Eosin staining procedure was used to assess breast tissues of experimental animals. Cancer antigen (CA) markers 15-3, 27-29 and carcinoembryonic antigen (CEA) in the blood of experimental animals were evaluated using an automated procedure. Quantitative phytochemical screening showed that Olax subscorpioidea and Newbouldia laevis contained alkaloid in the highest amount. Histopathological assay revealed the presence of stromal fibrosis in the breast tissues of 8 out of 10 rats administered with NMU. Levels of CA 15-3, CA 27-29, CEA were significantly (p &lt; 0.05) elevated in MNU administered group in comparison to the negative control. Treatment with Olax subscorpioidea leave extract significantly (p &lt; 0.05) ameliorated CA 15-3, CA 27-29 and CEA levels. However, treatment with Newbouldia laevis leave extract significantly (p &lt; 0.05) ameliorated CA 15-3 and CEA levels only. Findings from this study showed that ethanolic extracts of Olax subscorpioidea and Newbouldia laevis leaves have chemo-preventive activity in NMU-induced stroma fibrosis in the breast tissue of female albino rats. However more studies on the discovery and validation of bioactive components of the plants are needed.

МОРФОЛОГИЧЕСКИЕ АСПЕКТЫ БИОИНТЕГРАЦИИ ФТОРСОДЕРЖАЩИХ ПОЛИМЕРОВ В ЭКСПЕРИМЕНТЕ

Background. There exist strict requirements for polymer materials to be used for implantation into living organisms, thus, no substance lacking negative properties has been found yet. Various groups of polymers are currently under research, including fluorinated polytetrafluoroethylene families. Objective. To evaluate the peculiarities of morphological reactions that occur during implantation of Belarusian fluoroplast-4 into various tissues of experimental animals. Material and methods. The experiments were carried out on outbred white rats weighing 200-250 g, which were divided into four groups. In rats of the first group, a 5×10 mm liver wound was closed with a fluoroplast-4 fragment, in those of the second – with fluoroplast-4 modified by «Photolon» and calcium chloride, in those of the third - a flap of highly porous fluoroplast-4 was implanted into a 5×5×5 mm hip muscle defect, in those of the fourth - a flap of lowporous fluoroplast-4 was used. The morphology of surrounding tissues and that of an implant were studied at various points of time after surgery using light microscopy and morphometry. Results. Surgical trauma resulting from operation on various tissues followed by plasty using fluoroplast-4 activates a sequence of pathomorphological inflammatory-reparative processes, including three classical stages of inflammation and has a reversible character. Polymer materials act as a framework over which the synthetic material is both isolated by collagen fibers and integrated through the ingrowth of the latter into the pores of the polymer, resulting in the formation of a new connective tissue capsule. Conclusions. Fluorinated polymer materials originally manufactured in the Republic of Belarus are biocompatible polymers that can be used in functionally active areas.

Toxicity of Nanoscaled Zero-Valent Iron Particles on Tilapia, Oreochromis mossambicus.

This research effort aims to evaluate the hazardous potential of the redox state (OH-) of zero-valent iron nanoparticles (nZVI) and its histopathological and oxidative stress toward Mozambique tilapia, Oreochromis mossambicus. X-ray powder diffraction (XRD) validated the nZVI nanoparticles' chemical composition, while transmission electron microscopy (TEM) revealed that their physical form is round and oval. The exposure to 10 g/mL of nZVI induced the activation of the cellular superoxide dismutase (SOD) activity. Dose-dependent testing of O. mossambicus had a reduction in SOD and an increase in malondialdehyde (MDA) levels, suggesting that nZVI caused oxidative damage. At a concentration of 100 g/mL, the catalase (CAT) and peroxidase (POD) activities of diverse tissues exhibited a gradual decrease after 2 days of exposure and a fast increase until day 6. The scavenging of reactive oxygen species (ROS) in the epidermis, liver, and gills of O. mossambicus deteriorated and accumulated gradually. MDA levels in the skin, gill, and liver tissues were substantially higher after 8 days of exposure to 100 and 200 g/mL nZVI compared to those of the control group and those exposed to 10 and 50 g/mL nZVI for 2 days. Extreme histological and morphological abnormalities were seen in the skin, gill, and liver tissues of experimental animals, demonstrating that the damage resulted from direct contact with nZVI in water. A one-way ANOVA followed by Dunnett's post-test was performed to investigate significant differences.

Possibilities of antifibrotic therapy and correction of cognitive disorders in experimentally induced severe liver fibrosis and cirrhosis in rats

BACKGROUND: The main pathogenetic aspects of the correction of cognitive impairment of the brain and antifibrotic therapy against the background of experimentally induced severe fibrosis and cirrhosis of the liver in rats are considered. Viral hepatitis of various etiologies is one of the main problems of modern health care. The incidence of viral hepatitis is 30 million cases per year. Mortality from complications of acute viral hepatitis, such as cirrhosis of the liver and hepatocellular carcinoma, reaches 1.4 million cases per year. At the same time, in some cases, etiotropic therapy does not provide stabilization or regression of fibrotic changes in the liver tissue in comorbid patients, as well as in patients receiving antiviral therapy at the stages of severe fibrosis and compensated liver cirrhosis, which requires the search for new therapeutic approaches related to, first of all, with the possibility of influencing non-specific processes of fibrogenesis. Hepatic encephalopathy in such patients leads to the appearance of behavioral, cognitive and motor disorders of varying severity, thereby having a negative impact on the operators function in such professions as pilots, dispatchers, in a number of military specialties, etc. Thus, therapy aimed at the key links of pathogenesis often plays a decisive role in the treatment of liver diseases, especially in the later stages.&#x0D; AIM: To identify the presence and severity of cognitive impairment in rats with induced severe liver fibrosis and liver cirrhosis before and after therapy with Bicyclol and to assess the degree of its antifibrotic effect.&#x0D; MATERIALS AND METHODS: The study included 70 male Wistar rats weighing 180200 g, in which toxic fibrosis and cirrhosis of the liver were induced at stages F3 and F4. The control group consisted of 10 individuals who received a normal diet, the experimental group 24, who, in addition to the standard diet, were prescribed the drug Bicyclol. The assessment of cognitive impairment of the brain was carried out using a test with a hidden platform in the Morris water maze and statistical analysis. The evaluation of the results of the use of the drug was carried out using histological examination, methods of biochemical, molecular biological and statistical analysis.&#x0D; RESULTS: The use of the drug Bicyclol leads to a marked decrease in fibrotic changes in the liver tissue of experimental animals and was accompanied by a temporary decrease in the activity of alanine aminotransferase in blood serum. Against the background of the development of induced toxic fibrosis and cirrhosis of the liver in rats, cognitive dysfunctions of the brain were observed, which significantly decreased against the background of the use of the drug Bicyclol.&#x0D; CONCLUSION: Results The use of bicyclol for 4 weeks in laboratory animals with induced severe liver fibrosis led to a long-lasting decrease in the severity of fibrotic changes in liver tissue, as well as to the regression of cirrhosis in rats with liver cirrhosis. These changes were accompanied by a decrease in cognitive impairment in rats of these subgroups, as evidenced by an improvement in the estimated indicators when performing a control complex in a Morris water maze with a hidden platform.

Comparative analysis of residual neurovirulence of vaccine and low attenuated rubella virus (Matonaviridae: Rubivirus: Rubella virus) strains in the experiments on the macaque rhesus (Macaca mulatta) monkeys

Rubella is currently an infection controlled by specific prophylaxis. Not only the right vaccine prophylaxis strategy and tactics, but also the use of effective and safe vaccine preparations is crucial for the elimination of this disease.The aim of the investigation was to study the morphological and pathogenetic patterns of changes developing in the central nervous system (CNS) and internal organs of monkeys (Haplorhini) during intracerebral inoculation with 2 strains of rubella virus (Matonaviridae: Rubivirus: Rubella virus) (RV): highly attenuated Orlov-B, and low attenuated Orlov-14. In the experiments, seronegative rhesus macaque monkeys (Macaca mulatta) weighing 3.3-5.1 kg (n = 7) were used. Neurovirulence of the strains was determined by a complex of clinical, pathomorphological, and virological methods. It was found that during attenuation, the Orlov-B strain lost the ability to replicate in CNS cells and induce moderate/expressed specific changes in them, as well as to overcome the blood-brain barrier and cause the damage of sensitive organs and tissues. This fact indicates a low level of residual neurovirulence of the vaccine strain. The results obtained in this study regarding the clinical symptoms of CNS lesions and the nature of the pathological process in its tissues in experimental animals can be significant for the improvement of safety control of live rubella vaccines. These data indicate that the Orlov-B strain can be considered as a candidate strain for further study on the development of a rubella vaccine based on the domestic vaccine strain.