Volume 166, Nº 1 (2018)

We studied the participation of DNA-methylation processes in the mechanisms of memory storage and reconsolidation, amnesia induction, and in recovery of the conditioned food aversion memory in edible snails. It was found that daily injections of DNA methyltransferases inhibitor over 3 days combined with a reminder of a conditioned food stimulus did not affect memory storage. The administration of DNA methyltransferase inhibitors did not suppress induction of amnesia caused the NMDA receptor antagonist/reminder. Injections of DNA methyltransferase inhibitors combined with the reminder led to memory recovery in 3 days after amnesia induction. Thus, DNA methyltransferase inhibitors in the same doses did not affect storage and reconsolidation of memory, as well as the mechanisms of amnesia induction. At the same time, injections of inhibitors led to memory recovery, apparently, due to disruption of reactivation and amnesia development.

The effect of phenolic antioxidants (dihydroquercetin, p-tyrosol, dibornol) on the morphology, functions, and redox processes in the reproductive cells of male rats was studied on the model of experimental pathospermia. All antioxidants reduced the percentage of degenerative forms of spermatozoa. Dibornol was most effective. Dihydroquercetin and p-tyrosol did not increase the total number of spermatozoa and the percentage of their mobile forms. These indicators were improved only by dibornol. After administration of all test drugs, the antioxidant potential of spermatozoa increased and did not significantly differ from the baseline values.

We studied serum content of some polyunsaturated fatty acids and their correlations with parameters of oxidative stress (FORT), antioxidant protection (FORD), lipoprotein-associated phospholipase A2 (LP-PLA2), and serum level of LPO products in male patients with coronary atherosclerosis. The mass fraction of polyunsaturated fatty acids and FORD were lower, while LP-PLA2, FORT, and concentration of LPO products were higher than in the control group (conventionally healthy men). Negative correlations of medium strength of polyunsaturated fatty acids with inflammation markers and oxidative stress were revealed, which can indicate that the decrease in polyunsaturated fatty acids content is associated with enhanced generation of free radicals, and consequently with increased risk of early atherosclerosis development.

A cross-sectional study performed on a continuous sample of 32 patients (mean age 46.36±3.31 years) with gastroesophageal reflux disease and excess body weight showed that the disturbance of sympathetic/parasympathetic relationships, disruption of segmental and compensatory increase in the suprasegmental mechanisms of autonomic regulation determines the course of gastroesophageal reflux disease in these patients.

Changes in BP and HR were assessed after exposures increasing activity of angiotensin-converting enzyme: ionizing radiation, NO synthase inhibitor (L-NAME), and dexamethasone. Effects of dihydroquercetin and angiotensin-converting enzyme inhibitor enalapril on activity of this enzyme, BP, and HR were also evaluated under these exposures. Wistar male rats were subjected to X-ray irradiation in a dose of 2.5 Gy. Angiotensin-converting enzyme activity in the aorta sections was determined by Hip-His-Leu hydrolysis. BP and HR were recorded using a non-invasive tail-cuff method and PowerLab 8/35 software. BP and HR were not altered with the increase in activity of angiotensin-converting enzyme after irradiation. In case of prolonged (7 days) treatment with NO synthase inhibitor and dexamethasone, the increase in enzyme activity was accompanied by elevation of BP and, in the case of NO synthase inhibitor, HR reduction. Dihydroquercetin normalized the enzyme activity and lowered BP, but not to the normal level. Enalapril normalized BP, increased by NO synthase inhibitor solution intake; at the same time, the angiotensinconverting enzyme activity decreased more than 2-fold in comparison with the normal.

The effect of a cerebroprotective agent magnesium bis-aminoethanesulfonate (laboratory code FS-LKhT-317) on intracellular calcium concentration was studied by the fluorescent imaging technique on neuroglial cell culture from Spraque-Dawley rat hippocampus. The substance produced a pronounced inhibitory effect and suppressed NMDA receptor activity in concentrations of ≥50 μM. The observed effects were reversible or partially reversible and were detected by a decrease in Ca²⁺ signal amplitude in neurons in response to NMDA applications in a Mg²⁺-free medium and by inhibition of Ca²⁺ pulses in magnesium-free medium (elimination of magnesium block).

The effects of intramuscular administration of neostigmine and physostigmine on Na⁺,K⁺-ATPase activity in various cerebral subdivisions were examined in rats. In CNS and peripheral tissues, both agents rapidly and significantly reduced activity of cholinesterases by 30-50%. The development of intoxication did not change the marker indices of stress reaction. In the cerebral cortex, physostigmine increased Na⁺,K⁺-ATPase activity, whereas neostigmine suppressed it. In addition, neostigmine decreased activity of this enzyme in the cerebellum. In contrast, both agents produced no effects on Na⁺,K⁺-ATPase activity in the striatum. The data corroborate the view on functional interaction between Na⁺,K⁺-ATPase and nicotinic cholinoreceptors in rat cerebral cortex.

We studied the effect of different concentrations of polyelectrolytes poly(allylamine hydrochloride) (PAH) and polystyrene sulfonate (PSS) as well as the effects of microcapsules coated with these polymers on survival of Ehrlich ascites carcinoma cells and mouse peritoneal macrophages and on ROS production by phagocytes. PAH reduced viability of Ehrlich ascites carcinoma in a concentration-dependent manner (LD₅₀=12-15 μg/ml). This effect was presumably determined by its ability to bind phosphates, thereby depleting the culture medium. At the same time, PAH did not affect the viability of macrophages. PSS produced no cytotoxic effect on the examined cells. Polyelectrolyte capsules with the shell architectonics (PAH/PSS)₃ and (PAH/PSS)₃PAH in the examined concentration range had no effect on the viability of macrophages and tumor cells. PAH microcapsules with positively charged surface much more rapidly and more intensively activated macrophages. The chemiluminescence response directly depended on the amount of capsules in the solution.

We performed a complex morphological study of samples of different types of unstable atherosclerotic plaques obtained from 33 men with occlusive coronary atherosclerosis, who underwent coronary artery endarterectomy during coronary artery bypass surgery. In the samples, expression of MMP-2 and MMP-9, collagen IV, CD31, CD34, factor VIII, and actin of smooth muscle cells was evaluated by morphometric and immunohistochemical methods. The maximum expression of MMP-9 was found in unstable plaques of the lipid type, where it 1.4- and 1.24-fold surpassed the corresponding levels in plaques of the inflammatory-erosive and degenerative-necrotic types. Unstable plaques of the degenerative-necrotic type are characterized by the most intensive expression of collagen IV in comparison with plaques of the inflammatory-erosive and lipid types (by 2.8 and 2.2 times, respectively). The maximum neovascularization was detected in inflammatory-erosive plaques, which was confirmed by enhanced expression of CD31 and CD34 markers in comparison with plaques of the lipid (by 7.6 and 18.95 times, respectively) and degenerative-necrotic (by 31.1 and 39.8 times) types.

Human umbilical cord represents a source of multipotent stromal cells of a supreme therapeutic potential. The cells can be isolated from either fresh or cryopreserved umbilical cord tissues. DMSO is a cryoprotectant most commonly used for preservation of umbilical cord tissues; however, cyto- and genotoxicity of this compound is evident and well documented. In the present study we performed successful cryopreservation of the umbilical cord tissue using other cryoprotectants: propylene glycol, ethylene glycol, and glycerol. Of these, 1.5 M ethylene glycol and 20% glycerol turned out to be the best in terms of the preservation of living cells within the frozen tissue, early onset of migration of these cells out of the thawed explants, and overall efficacy of multipotent stromal cell isolation. Cryobanking of tissues can improve availability of multiple cell products for medical purposes and promote the development of personalized medicine.

TLR2-mediated ROS production by mouse peritoneal macrophages was studied by luminoldependent chemiluminescence under conditions of cell stimulation with zymosan (TLR2/6 ligand) and peptidoglycan (TLR2/1 ligand). ROS production by macrophages stimulated with zymosan and peptidoglycan simultaneously depended on the ratio of ligand concentrations. Three effects were revealed: additivity of the stimulating effects of the ligands used, competitive ligand binding, and effect of macrophage priming with peptidoglycan during cell stimulation with zymosan. The mechanisms of these effects are discussed.

Antioxidant activity of a pharmaceutical substance hypocard was compared with activity of nitromalic acid and well-known agents nicorandil and Mexidol. The ability of these substances to inhibit spontaneous and oxidant-induced LPO process in rat brain homogenate was analyzed. The mechanisms of these effects were studied. The antioxidant properties of hypocard manifested in the inhibition of Fe(II)-induced LPO were significantly more pronounced in comparison with Mexidol and nicorandil.

Replicative ability of 5 oncolytic enterovirus strains was evaluated on a panel of 18 human normal and tumor cells. The capacity of each cell line to support replication of enterovirus strains varied. Cell lines weakly replicating one virus could be highly sensitive to another viral strain. Differences in the expression of CXADR cell receptor did not correlate with susceptibility to infection and replication of Coxsackie B virus, but complete inactivation of CXADR gene and poliovirus receptor gene (PVR) led to loss of the sensitivity to Coxsackie B5 and poliovirus, respectively. Detection of additional expression markers will contribute to understanding the causes of different sensitivity of tumor cells to viruses.

We studied myelotoxicity of modern schemes of chemotherapy for breast cancer (docetaxel/doxorubicin and cyclophosphamide/doxorubicin/5-fluorouracil) towards granulocytopoiesis, the mechanisms determining the differences of hematological effects of these schemes, and the efficiency of correction of the observed changes with granulocyte CSF (filgrastim). Granulocytopoiesis stimulation with filgrastim during the treatment with docetaxel/doxorubicin combination was more pronounced than during cyclophosphamide/doxorubicin/5-fluorouracil therapy. The observed differences were found at all levels of granulocyte lineage organization (central and peripheral), which is related to different effects of the cytostatic substances used in the proposed protocols on the structures controlling hemopoiesis.

We studied the effect of oral administration of metallic silver nanoparticles to rats on the proteome of the liver microsomal fraction. Nanoparticles (5-80 nm) were administered daily to growing Wistar male rats over 92 days. Controls received pure water. To control the effect of the carrier, the rats were administered aqueous solution of a stabilizer polyvinylpyrrolidone. The protein composition (proteome) of the liver microsomal fraction was analyzed by 2D-electrophoresis with identification of variable protein spots using the high-resolution nanoHPLC-MS/MS. Eight, 6, and 8 proteins absent in the control groups appeared in the microsomal fraction under the action of nanoparticles in doses of 0.1, 1, and 10 mg/kg body weight, among these, proteasome activator complex subunit 1 (Psme1 gene), and the heat shock protein HSP60 (Hspd1 gene) were reliably identified. The consumption of silver nanoparticles led to disappearance of protein of β2a tubulin chain (Tuba1b gene) from the microsomal fraction. The expression of catalase, present in the proteome of the liver microsomal fraction in animals of all groups was significantly decreased after consumption of silver nanoparticles in doses of 0.1 and 10 mg/kg. The observed changes in the proteome are considered as manifestations of hepatotoxicity of silver nanoparticles and can be related to the antagonistic effect of silver on the status of the essential trace element selenium.

The effect of selective antagonist of the arginine vasopressin (AVP) V1b receptors on the secretion of ACTH and corticosteroids in response to insulin-induced hypoglycemia and injection of AVP is studied in old Macaca mulatta females with depression-like and anxious behavior. Intravenous antagonist in a dose of 1.1-1.7 μg/kg inhibits the increase of ACTH concentration, induced by hypoglycemia or injection of AVP. The degree of increase in the concentrations of hydrocortisone and dehydroepiandrosterone sulfate has not changed or increased. The effects of AVP antagonist prove that previously detected disorders in the reaction of the hypothalamic—pituitary—adrenal system in old Macaca mulatta with depression-like and anxious behavior could be caused by excessive activation of vasopressin V1b receptors on the pituitary corticotrophs, while the use of V1b receptor antagonists seems to be a promising method for prevention of these disorders.

We analyzed the concentration of extracellular DNA and its fractions in the dynamics of uncomplicated pregnancy Thirty women with singleton pregnancy were examined. The concentration of total, maternal, and fetal cell-free DNA in maternal blood was measured at gestation weeks 11-14, 24-26, and 30-32. The level of total cell-free DNA was evaluated by measuring the concentration of RASSF1A gene using quantitative PCR analysis, the level of cell-free fetal DNA was assessed by determining the hypermethylated part of RASSF1A gene. The concentration of total cell-free DNA and cell-free maternal DNA did not change during the first half of pregnancy, but increased after 24-26 weeks. The level of cell-free fetal DNA increased from the first to the second and third trimester: 14.15 (2.32-36.25), 24.87 (6.29-129.32), and 32.62 (8.97-133.52) GE/ml (p<0.05), respectively. Our results characterize the dynamics of the content of cell-free DNA and its fractions during pregnancy, which should be taken into account when using cell-free DNA for prediction of placenta-associated complications.

Integral, biochemical, and morphological parameters and concentrations of vitamins, particularly lipid soluble vitamins, were analyzed in female mice of inbred DBA/2J line, outbred ICR-1 (CD-1) line, and DBCB tetrahybrid mice on the in vivo model of metabolic syndrome induced by consumption of 30% sucrose for 2 days. In contrast to inbred and outbred lines, DBCB tetrahybrid mice developed abdominal obesity, hypercholesterolemia, and pronounced morphological picture of fatty liver disease. The lipid-coupled transport of vitamin E to the liver is also enhanced in these animals, which compensated decreased supply of vitamin E to the liver under conditions of high-sugar ration. The observed interstrain differences can be related to genetic features of the used mouse lines and DBCB tetrahybrid mice and require further genomic, transcriptomic, proteomic, and morphological studies. The results of the study based on the in vivo model of metabolic syndrome allow identifying the key biomarkers for complex diagnostics and prognosis of metabolic syndrome complications, such as nonalcoholic steatosis of the liver.

Modern medical approaches to the therapy of various diseases, including cancer, are based on the use of toxic drugs. The unfavorable side effects of traditional medicine could be counterbalanced by addition of natural bioactive substances to conventional therapy due to their mild action on cells combined with the multitargeted effects. To elucidate the real mechanisms of their biological activity, versatile approaches including a number of “omics” such as genomics, transcriptomics, proteomics, and metabolomics are used. This review highlights inclusion of bioactive natural compounds into the therapy of chronic diseases from the viewpoint of modern omics-based nutritional biochemistry. The recently accumulated data argue for necessity to employ nutrigenetic and nutrimetabolomic analyses to prevent or diminish the risk of chronic diseases.

We studied survival of rat ensheathing cells after transplantation into experimental posttraumatic cysts. These cells were prepared according to our original protocol, labeled with intravital membrane dye PKH26, and transplanted into posttraumatic cysts of the spinal cord. The presence of cysts was verified by magnetic resonance imaging. Olfactory ensheathing cells were detected in the spinal cord by the immunofluorescence method. It was shown that rat olfactory ensheathing cells survived in the spinal cord over 4 weeks and their migration was observed. High survival rate and the possibility of obtaining olfactory ensheathing cells from the olfactory mucosa of patients for creation of an autologous preparation allow considering them as very promising material for the treatment of patients with posttraumatic cysts of the spinal cord.

Production of microvesicles in culture of human umbilical cord multipotent mesenchymal stromal cells was studied and comparative analysis of the expression of some surface molecules (clusters of differentiation, CD) was performed. It was found that the mesenchymal stromal cells produce microvesicles in the amount sufficient for their detection by flow cytometry. Parallel analysis of the phenotypes of maternal mesenchymal stromal cells and secreted microvesicles revealed identical expression of surface molecules CD13, CD29, CD44, CD54, CD71, CD73, CD90, CD105, CD106, and HLA-I. The concentration of microvesicles in the conditioned medium was 17.9±4.6×10⁶/ml; i.e. one cell produced ~40-50 (44.7±11.5) microvesicles over 2 days in culture.

The data on cancer stem cell surface molecular markers of 27 most common cancer diseases were analyzed using natural language processing and data mining techniques. As a source, 8933 full-text open-access English-language scientific articles available on the Internet were used. Text mining was based on searching for three entities within one sentence, namely a tumor name, a phrase “cancer stem cells” or its synonym, and a name of differentiation cluster molecule. As a result, a list of surface molecular markers was formed that included markers most frequently mentioned in the context of certain tumor diseases and used in studies of human and animal tumor cells. Based on similarity of the associated markers, the tumors were divided into five groups.

Vascularization of bioengineered bone tissue constructs remains a challenging problem of regenerative medicine. Spheroids generated in 3D culture of adipose-derived stromal cells supplemented with inducing factors demonstrate stable characteristics and express of mesenchymal, endothelial, and osteoblasts markers, and represent a prototype of vascularized microtissue. Adipose-derived stromal cells spheroids induced to both angio- and osteogenic differentiation can be used in development of new innovative technologies for in vitro fabrication of vascularized bioequivalents for repair of large bone defects.

We propose a cell model of the human small intestinal wall based on genetically modified Caco-2 cells that allows visualization and quantitative assessment of activation of NF-κB factor and related intracellular pathway by using fluorescence microscopy. A dose-dependent increase in fluorescence intensity of the obtained cells in response to TNFα exposure in concentrations of 1-100 ng/ml was demonstrated. It was found that this parameter correlates with a decrease in the transepithelial resistance of the cell monolayer in response to TNFα and can be used to assess the toxic effects of substances on epithelial cells of the human small intestine.