Using zebrafish (Danio rerio) as a model organism, we studied metabolomic markers of β-blocker neurotoxicity (propranolol, metoprolol, bisoprolol) and the relationships between neurotransmitter disturbances (dopamine, epinephrine, choline, cortisol) and their effects. Propranolol produced the most pronounced changes: significant increases in cortisol and epinephrine and decreases in dopamine and serotonin levels. Metoprolol caused a moderate increase in cortisol while elevating serotonin, suggesting a more balanced pharmacological profile. Bisoprolol had virtually no effect on cortisol or monoamine levels but increased the concentrations of choline, glycine, and glutamate. Differences in neurometabolic effects of β-blockers were identified: propranolol demonstrated a strong neurotoxic potential, consistent with its depressive side effects in humans; metoprolol showed an intermediate effect; while bisoprolol did not affect CNS. Zebrafish exhibited high sensitivity to neurochemical shifts, making this model valuable for preclinical drug neurotoxicity assessment.

The composition of the microbial community of the small intestine of rats under chronic restraint stress of varying duration (14 and 28 days) was studied. Identification and quantitative determination of microorganisms were carried out using gas chromatography-mass spectrometry of microbial markers. It was found that under stress exposure, the number of Bifidobacterium spp., Lactobacillus spp., Enterococcus spp., Enterobacteriaceae spp., Actinomyces viscosus, Nocardia asteroides, Clostridium tetani, Clostridium ramosum decreased and the number of Clostridium difficile, Helicobacter pylori, Streptococcus mutans, Propionibacterium freudenreichii, Peptostreptococcus anaerobius increased. It was shown that enterococci are capable of self-restoring their population levels under stress conditions, whereas bifidobacteria, lactobacilli and enterobacteria do not exhibit adaptive capacity.

In the streptozotocin-nicotinamide model of type 2 diabetes mellitus (T2DM), erythrocytes exhibit increased resistance to osmotic and colloid-osmotic lysis. For thymocytes, cell volume regulation in T2DM was found to be significantly less effective than in the control. Using the Langendorff isolated heart retrograde perfusion model, we demonstrated that reperfusion after 30-min global ischemia leads to a dramatic decrease in HR, a decrease in left-ventricular systolic pressure, left-ventricular developed pressure, and the rate of left-ventricular pressure rise and fall. While the general pattern of heart dynamics during ischemia/reperfusion was preserved in T2DM, post-reperfusion HR was significantly lower than in the control.

The paper describes the effect of a plant extract composition on the metabolism of extracellular matrix (ECM) components in the liver of rats fed a high-fat diet. High-fat diet for 4 weeks increased the content of sulfated glycosaminoglycans, and activation of collagen metabolism and suppression of hyaluronidase activity were detected after 7 weeks. These changes created favorable conditions for fibrogenesis stimulation. The balance between MMP9 and TIMP-1 activities was preserved, but neither severe nor moderate changes in liver ECM were noted at the structural level. Phytocomposition administered against the background of the high-fat diet alleviated pathological remodeling of ECM, which may represent a key mechanism of its action.

Structural changes in the thymus of female Wistar rats with chemically induced breast cancer after photodynamic therapy (PDT) followed by surgical resection and chemotherapy (doxorubicin) were studied by histological methods. Structural changes in the thymus after this multimodal treatment may indicate enhanced proliferation of cells in the cortex (cortical substance is enlarged), activation of both positive and negative selection T cells, and intensification of T-cell differentiation and migration from the thymus.

The intensity of accumulation and excretion of atrial natriuretic peptide (ANP) in right atrial myocytes of 1-day-old offspring born to female rats with streptozotocin-induced type 1 diabetes mellitus was studied using transmission electron microscopy and immunocytochemistry. The data indicate a reduced ANP content relative to the control group. No significant differences were found in the morphometric characteristics of the right atrium ultrastructure between the control and experimental groups.

In a longitudinal study of permanent Arctic residents, an actigraphic analysis of sleep quality indicators across different seasons revealed no significant overall seasonal differences in sleep efficiency (p = 0.487). However, TT homozygotes for the CLOCK gene rs1801260 polymorphism the exhibited lower sleep efficiency, particularly in spring and summer. Multiple linear regression, incorporating categorical covariates including rs1801260 polymorphism, sex, season, indigenous status, age, and body mass index, identified the TT genotype as the sole significant predictor of sleep efficiency (β = -0.215; p = 0.029), confirming its association with poorer sleep quality.

We investigated the effect of the nucleoside uridine on the activities of key enzymes of oxidative phosphorylation (succinate dehydrogenase, SDH) and glycolysis (lactate dehydrogenase, LDH) in peripheral blood lymphocytes, and on oxidative metabolism in the blood serum of rats in the rotenone and 6-OHDA models of Parkinson's disease. Both models were characterized by increased SDH and LDH activities in lymphocytes and accumulation of lipid peroxides in the blood serum. Injections of uridine, affecting the functioning of mitochondrial K-ATP channel (mitoKATP), to animals at a dose of 30 mg/kg body weight for 28 days mitigated SDH and LDH hyperactivation in lymphocytes and reduced the serum level of LPO products. Specific mitoKATP inhibitor 5-hydroxydecanoate (5 mg/kg) eliminated the effect of uridine. The role of mitoKATP in the protective effect of uridine in a model of Parkinson's disease is discussed.

We analyzed physicochemical properties and antigenic activity of cell envelope preparations isolated from urea lysates of different Francisella tularensis subspecies. Lysis of F. tularensis cells with a urea solution yielded polyepitopic immunogenic complexes with high antigenic activity detected in specific immunochemical reactions (dot immunoassay, immunoblotting, radial immunodiffusion) with IgG isolated from commercial horse tularemia serum and labeled with colloidal silver nanoparticles.

We studied the effect of 14.5 MeV neutron dose ultrafractionation on survival and recovery kinetics from radiation damage in normal V-79 and tumor B14-150 cells. Neutron doses of 0.5, 2, 4, and 6 Gy were split into 1, 2, 3, and 4 fractions. The observed recovery times 1.6 h (V-79) and 0.94 h (B14-150) indicate the possibility of reducing radiation damage with increasing the number of fractions. It was shown that neutron irradiation efficacy decreases when intervals between fractions exceed 1 h.