Aim. To characterize iNOS expression indicators in the basal magnocellular nucleus of rats during early pathogenetic correction of neurodegeneration induced by intracerebroventricular colchicine administration. Materials and methods. The study was conducted using 50 male Wistar rats aged 10–11 months, which were divided into 5 experimental groups (n = 10). The control animals (group 1) were administered a 0.9 % NaCl solution intracerebroventricularly, while the other experimental group rats (groups 2–5) received a colchicine solution in the same manner. The following day, the animals from groups 3–5 were initiated early pathogenetic correction with citicoline (group 3), thiocetam (group 4), and HSF-1 (group 5) lasting 14 days. All the experimental animals (groups 1–5) were then euthanized with sodium thiopental, and their brains were extracted for histochemical, immunofluorescent, and biochemical examinations. Results. The study has demonstrated that intracerebroventricular administration of colchicine to rats was accompanied by morphological signs of neurodegeneration in the basal magnocellular nucleus and characterized by a significantly smaller area of chromaffin substance in the neurons of this structure by 39 % as compared to the control animals. At the same time, early pathogenetic correction of colchicine-induced neurodegeneration was associated with significantly larger values of Nissl substance area of the basal magnocellular nucleus neurons compared to the corresponding values in animals that did not receive the correction. Additionally, the nitrite level in the brain homogenates of rats administered colchicine without correction (group 2) exceeded the control (group 1) by almost 7 times, while the indicators in experimental groups 3, 4, and 5 exceeded it by 3.5, 2.9, and 3.8 times, respectively. However, no statistical differences were found between the control group and the correction groups in terms of nitrite content. Evaluating the expression of iNOS (the area of immunopositive cells and corrected total cell fluorescence, CTCF) in the basal magnocellular nucleus of the experimental rats it has been shown that the area was most affected in group 5 (HSF-1 correction), exceeding the control parameter by 18.9 %, group 3 (citicoline correction) by 14.7 %, and group 4 (thiocetam correction) by 17.1 %, with no statistical differences compared to group 2 (colchicine administration without correction). Meanwhile, the CTCF of iNOS+-cells in the basal magnocellular nucleus of the experimental animals was the highest in group 2 significantly exceeding the corresponding parameters in the control and correction groups. No significant differences were found between the control and correction groups in this parameter. Additionally, it is noteworthy that intracerebroventricular administration of colchicine to rats, compared to control animals, was associated with a significant double the number of iNOS+ cells in the basal magnocellular nucleus. However, early pathogenetic correction in groups 3-5 did not significantly affect the number of iNOS+ cells in the studied structure, as this parameter did not statistically differ from group 2, although significantly exceeding the corresponding parameter in the control group (group 1). Conclusions. Early pathogenetically substantiated correction with citicoline, thiocetam, and HSF-1 in colchicine-induced neurodegeneration in the basal magnocellular nucleus of experimental rats is accompanied by an increase in the area of chromaffin substance compared to rats that received intracerebroventricular colchicine without correction, as well as a reduction in nitrite levels in brain homogenates to the control level (sham-operated animals). In the basal magnocellular nucleus of experimental rats, under the influence of early pathogenetically substantiated correction of experimental neurodegeneration, iNOS expression indicators (area of immunopositive cells and CTCF) vary depending on the neuroprotectant used. The number of iNOS+ cells in the basal magnocellular nucleus of experimental rats in the correction groups does not change compared to the group that received intracerebroventricular colchicine without correction and is statistically higher than the corresponding indicator in the control rats.

The aim was to recreate an experimental model of insulin resistance in male Wistar rats by using a diet with a high fat content of combined origin. Materials and methods. 42 male Wistar rats were taken into the experiment and divided into 2 groups: 1st – control (n = 7) and 2nd – experimental (n = 35). For modelling the insulin resistance (IRS) the rats were fed with a commercial compound feed with a fat content of 40 % for 8 weeks. To control the dynamics of metabolic changes, the rats of the experimental groups were weighed weekly, fasting glucose was measured once every 2 weeks, a glucose tolerance test (GTT), blood pressure measurement (BP) and body composition bioimpedance analysis (BIS) were performed once every 4 weeks, and an insulin tolerance test (ITT) was performed once at 8 week after receiving convincing changes in the glucose tolerance test. Results. In rats of the IRS group, compared to the control group, body weight exceeded the control group by 13 % on the 4th week and by 9 % on the 8th week; fasting glucose concentration was higher by 11 % on the 4th week and by 37 % on the 8th week; GTT revealed changes towards impaired glucose tolerance at both periods, however, the hyperglycemic type of curve was detected on the 8th week, which was combinated by the absence of significant glucose changes during ITT; on the 4th week – systolic BP increase by 27 % and diastolic – by 6 %, and on the 8th week – by 21 % and 20 %, respectively; BIS on the 4th week revealed an increase in body fat mass, against which latent general dehydration with redistributive extracellular hyperhydration is formed, on the 8th week – progression of obesity and dehydration, but with redistribution of fluid towards intracellular hyperhydration. Conclusions. Feeding animals a high-fat diet of combined origin for 4 weeks led to obesity, as evidenced by increased body weight and body fat mass with altered fat distribution. This was accompanied by latent general dehydration and extracellular hyperhydration. However, 4 weeks was insufficient to induce insulin resistance. Extending the diet to 8 weeks resulted in further obesity progression and the development of insulin resistance, characterized by fasting hyperglycemia, a hyperglycemic-type curve on the GTT, the absence of significant glucose fluctuations during ITT, and persistently elevated BP. These metabolic disturbances contributed to a relative total body water deficit, driven by extracellular dehydration with fluid redistribution towards intracellular hyperhydration.

The aim was to determine the body composition of rats with experimental type 1 diabetes mellitus and its correction with amino acids using bioimpedance analysis. Material and methods. Diabetes mellitus was modeled by the injection of streptozotocin. On the 6th week the rats were divided into 3 subgroups: DM1-1 – without correction, DM1-2 – correction with L-arginine and DM1-3 – correction with N-acetyl-L-cysteine for 2 weeks. Body composition was determined by the Vet BIS1 impedance analyzer with a study of total water volume in the body, extracellular and intracellular fluid, fat and fat-free body mass. Results. Weight of rats in DM1 group at the 6th week was 40 % less than in control, with a 63 % reduction in fat and 22 % decrease of fat-free body mass. The development of hyperglycemia in week 6 caused general dehydration, with a decrease in absolute values of both fluid volumes. On the 7th and 8th weeks, body weight, fat and fat-free body mass in the subgroups DM1-1, DM1-2, and DM1-3 did not differ statistically. Both amino acids caused a decrease in glucose concentration, but this did not affect existing total dehydration with a decrease of both fluid volumes. Conclusions. The development of streptozotocin-induced type 1 diabetes mellitus in rats in 6 weeks resulted in a statistically significant loss of body weight, mostly due to fat mass decrease with a violation of its ratio to fat-free mass. Persistent hyperglycemia already in the 6th week of experimental diabetes mellitus causes general dehydration due to loss of extracellular and intracellular water, with a predominance of intracellular dehydration. Two-week correction of diabetes with L-arginine and N-acetyl-L-cysteine at 8th week significantly reduces glucose concentration in subgroups, but does not affect the progressive reduction of body weight, fat and free-fat mass, and fluid volumes.

Aim of the study was to characterize the locomotor and cognitive aspects of the behavior of experimental rats under intracerebroventricular colchicine administration in the open field test and the 8-arm radial maze, as well as identify a set of behavioral features of experimental animals that emerged during the study. Materials and methods. The study was conducted in two stages on 20 male Wistar rats aged 10–11 months. The first stage involved assessment of initial locomotor activity and cognitive functions in all intact rats. At the next stage, the rats were divided into two experimental groups (n = 10): the first group with intracerebroventricular injection of physiological NaCl solution, and the second group with intracerebroventricular injection of colchicine. In 14 days after the surgery, repeated recording of locomotive and cognitive activity indicators was performed. Results. The locomotor activity characteristics did not statistically differ between the animals before the surgical procedures and the rats of the first group. However, in the second group, the activity indicators were significantly higher than in the respective pre-surgery rats. In the intergroup comparison of the rats that entered the second stage of the experiment, it was found that among all the investigated parameters, only the indicator of high activity duration was significantly higher in the second group compared to the first group. At the same time, the animals in the second group showed significant cognitive impairments compared to the first group, as indicated by significantly lower memory index values, the number of correct entries into the maze arms, and a significantly longer time to make the first correct entry into the maze arm. Conclusions. Intracerebroventricular administration of colchicine to experimental rats is accompanied by increased locomotor activity and impairment of cognitive functions. The administration of a physiological solution is not accompanied by a statistically significant increase in locomotor activity, but it demonstrates a clear tendency to increase, which may indicate a certain influence of the procedure itself. The applied pharmacological model of neurodegeneration with subsequent comprehensive assessment of animal behavior in an open field and an 8-arm radial maze is legitimate and can be used to study the early development of neuroinflammation, neuroapoptosis, and synaptogenesis disorders in the experiment.

Russia’s war against Ukraine has devastating humanitarian, social, economic and environmental consequences. To assess them, it is important to monitor environmental pollutants in the eastern regions of Ukraine. This study analyses the chemical composition of surface and groundwater near the frontline in Zaporizhzhia region and justifies the need to develop a state plan for the restoration of damaged areas. Aim. To study the content of environmental toxins, organic compounds and heavy metals in surface and ground waters in the south-east of Ukraine near the frontline and to identify areas of high risk of pollution. Materials and methods. During the period of 2024, 70 drinking water samples were collected and examined from the centralised water supply networks of the city of Zaporizhzhia of the Municipal Enterprise “Vodokanal” and Enterprise of State Criminal-Executive Service of Ukraine. Groundwater samples were taken by professional hydrogeologists on November 9, 2024, near Tarasivka village (geographical coordinates: 47°46′41′′N 35°26′36′′E / 47.77806°N 35.44333°E) and near Vilne village (geographical coordinates: 47.57286°N 32.61995°E) of Komyshuvakha village, Orikhiv district, Zaporizhzhia region, at a depth of 5, 14 and 190 meters. The water was not preserved and was delivered to the laboratory within a few hours. The chemical analysis was carried out in the laboratory of Ukrkhimanaliz LLC of the Center for Preventive Medicine of the State Administration of Affairs. The presence of heavy metals and organic compounds (50 indicators in total) was studied by atomic emission spectral, photometric, titrimetric, ionometric, colorimetric, chromatographic and calculation methods. Results. Analysis of 70 samples of drinking water in Zaporizhzhia from the centralised water supply networks of the Municipal Enterprise “Vodokanal” and Enterprise of State Criminal-Executive Service of Ukraine showed that 67–96 % did not meet hygiene standards for trihalogen methanes. Chemical analysis of groundwater showed significant contamination of aquifers at the 5- and 14-meter levels near the frontline due to a significant increase in nitrate and aluminium content. The groundwater was characterized by high levels of salts, sulphates, calcium and magnesium. Such groundwater quality indicators may be related both to the natural features of the area, namely the chemical composition of the soil, and man-made factors caused by the hostilities. The high mineralisation and hardness of the water, and the excessive content of nitrates and heavy metals (aluminium) made the water unsuitable for drinking purposes. At a depth of 190 meters (interstitial water – artesian water), no chemical pollutants were detected, and the organoleptic, sanitary and toxicological indicators met the sanitary and hygienic requirements according to State Sanitary Rules and Norms 2.2.4-171-10 “Hygienic Requirements for Drinking Water Intended for Human Consumption”. Conclusions. Drinking water from centralised water supply networks in Zaporizhzhia in 67–96 % of cases does not meet hygiene standards for trihalogen methanes. Groundwater in Zaporizhzhia region near the frontline at a depth of 5 and 14 meters is highly mineralised, containing high concentrations of nitrates and aluminium, making it unsuitable for drinking. The artesian water in this region does not contain pollutants of man-made and military origin, which indicates that the interlayer is not damaged, and this water is suitable for drinking. High levels of salt and general hardness of groundwater are associated with the geochemical features of the area. The high nitrate content and 1.4 times higher aluminium levels are the result of soil contamination in the area.

Intermittent hypoxia has been studied for many years as a promising non-pharmacological method of cardiovascular disease prevention. Hypoxic effects are accompanied by structural and functional changes in the myocardium. There is a direct link between the duration of hypoxic exposures and the severity of left ventricular myocardial remodeling. A range of histochemical markers of myocardial remodeling (cardiotrophin-1, titin, collagen type 1, annexin V) characterizing parenchymal-stromal relationships in the myocardium has shown high informativeness and prognostic value. The aim of the study was to examine cardiotrophin-1, titin, collagen type 1, annexin V and the morphofunctional state of the left ventricle of the heart in experimental rats exposed to intermittent 15-day (IH15) and 60-day hypoxia (IH60). Materials and methods. Intermittent hypoxia was modeled using 30 normotensive male Wistar rats, 7–8 months old, which were randomly assigned to 3 experimental groups of 10 animals each: 1) INT – a control group – intact animals (196.3 ± 6.8 g); 2) IH15 – 15-day hypoxia (205.6 ± 4.1 g); 3) IH60 – 60-day hypoxia (201.1 ± 5.5 g). The study compared the effects of intermittent hypoxia of varying duration: 15-day and 60-day hypoxia. Experimental modeling of intermittent hypoxia of 2 terms revealed a number of differences between the effects dependent on this factor duration through functional (blood pressure measurement, echocardiography) and immunofluorescent studies. Results. Blood pressure in rats of both groups was in the normotensive range, but an increase in systolic by 10 % and diastolic by 19 % was found in IH60 group compared to IH15 group (p < 0.05). In IH15 group, there was a significant decrease in end-diastolic dimension by 20 %, end-systolic dimension by 22 %, an increase in the thickness of left ventricular posterior wall by 44 % and interventricular septum by 33 % as well as left ventricular mass by 12 %, indicating concentric remodeling of the left ventricle, the development of which was confirmed by a 76 % increase in relative wall thickness compared to that in the control group (p < 0.05). Along with these changes, a decrease in end-diastolic volume by 47 %, end-systolic volume by 48 %, stroke volume by 49 % and cardiac output by 50 % with preserved ejection fraction was revealed (p < 0.05). While the parameters of IH60 rats were characterized by an increase in the thickness of interventricular septum by 33 % and left ventricular posterior wall by 17 %, as well as left ventricle mass by 23 %, relative left ventricular wall thickness was 15 % higher than the control value (p < 0.05). At the same time, diastolic volume was 9 % decreased and systolic volume was 24 % increased (p < 0.05). Also, cardiac output was increased by 58 % compared to that in 15-day hypoxic rats with an 8 % decrease in ejection fraction (p < 0.05). The concentrations of markers in IH60 group exceeded those in IH15, namely: cardiotrophin-1 by 39 %, titin by 70 %, collagen type 1 by 60 % and annexin V by 130 % (p < 0.05). Conclusions. 15-day hypoxia forms concentric left ventricular hypertrophy according to echocardiography findings; the study of marker profile of myocardial remodeling has revealed the development of moderate hypertrophy with increased resilient-elastic properties and decreased intensity of cardiomyocyte death. Remodeling caused by 60-day hypoxia is characterized by the eccentric pattern of changes with severe hypertrophy, significant fibrosis associated with apoptosis of cardiomyocytes. Such morphofunctional state of the myocardium may indicate the initial stages of maladaptation, increasing the risk of heart failure development.