Том 163, № 5 (2017)

Discrete mechanical stretch of isolated spontaneously contracting cardiac myocytes was employed to examine the kinetics of NO production in these cells. NO oscillations were detected with fluorescent dye 4-amino-5-methylamino-2’,7’-difluorofluorescein diacetate. The mechanisms underlying stretch-induced changes in NO concentration remain unclear and further studies are needed to evaluate the role of NO oscillation in the regulation of cardiomyocyte function.

The modulatory influence of diadenosine tetraphosphate (Ap4A) and diadenosine pentaphosphate (Ap5A) on the effect of intramural autonomic nerve stimulation in isolated rabbit sinoatrial node were examined. Electrical activity of the sinoatrial node was recorded intracellularly. Against the background of blockade of adrenergic effects with propranolol (3×10^—6 M) or in preparations isolated 2 h after injection of reserpine (2 mg/kg), nerve stimulation induced short-term membrane hyperpolarization and diminished the sinus node firing rate. These phenomena were not affected by Ap4A or Ap5A (10^—5 M). Under the action of atropine (3×10^—6 M) that completely eliminated the cholinergic influences, nerve stimulation enhanced the sinus node firing rate by 17.30±3.45% from the initial rate. Both Ap4A and Ap5A moderated the stimulation-induced elevation of firing rate to 9.9±2.8 and 10.5±2.9%, respectively. The data suggest that diadenosine polyphosphates significantly modulate the sympathetic influences on the heart rhythm, but have no effect on the parasympathetic control over activity of sinoatrial node.

We studied the effect of electroconvulsive therapy on cognitive functions in rats with depression-like disorder caused by exposure to ultrasound of varying frequency (20-45 kHz). Object recognition and Morris water-maze tests revealed no negative effects of the therapy on memory. Moreover, positive effect of therapy was demonstrated that manifested in amelioration of memory disturbances in depression-like disorders in these behavioral tests. The results of this study do not support the idea about side effects of electroconvulsive therapy, in particular, development of transient amnesia, and are a prerequisite for a more thorough study of internal mechanisms of the effect of the therapy on cognitive sphere.

In 60-day-old Wistar rats with fetal valproate syndrome, the brain to body weight ratio was higher by 9.4% and activity of dipeptidyl peptidase IV in the serum and cerebrospinal fluid was higher by 18.4 and 40.6%, respectively, than in healthy controls. Activity of prolylendopeptidase in the serum and cerebrospinal fluid in rats with the fetal valproate syndrome did not differ from the control.

We studied the dependence of post-rest positive inotropic response of isolated rat papillary muscles subjected to rhythmic stimulation on severity of postinfarction cardiosclerosis developed during 6 weeks after occlusion of the left descending coronary artery. The isolated papillary muscles were perfused with oxygenated Krebs—Henseleit solution and electrically stimulated at a rate of 0.5 Hz. In all rats, coronary occlusion provoked postinfarction cardiosclerosis with the formation of a scar occupying 20-50% (min-max of the sample) of the left ventricular wall. Despite the presence of large postinfarction scar in all rats, the positive post-rest inotropic responses greatly varied. The post-rest response in rats with scar occupying <37% left ventricular wall was similar to that in intact animals, but rats with scar area >44% demonstrated dramatically decreased inotropic response to rest periods.

The contents of cyclins A1, B1, E1, and D1, cyclin-dependent kinases 2 and 4 (CDK2 and CDK4), cyclin-dependent kinase 2C inhibitor (p18), and cyclin-dependent kinase 1C inhibitor (p57) in whole blood mononuclear cells of practically healthy donors and convalescents from community-acquired pneumonia were measured after cell exposure to low-intensity electromagnetic radiation of 1 GHz. The level of cyclins A1, D1, and B1, p57, and p18 proteins, and CDK2 was reduced in convalescents, while the content of cyclin B1 was elevated in both groups. A strong correlation was found between the content of cyclin B1 and the levels of cyclin A1 and CDK2 in convalescents. Single exposure of whole blood cells to 1-GHz microwaves was accompanied by an increase in the content of the analyzed factors (particularly, cyclins A1 and E1). These data indicate that radiation induced activation of the synthetic phase of the cell cycle.

The effects of the new structural analogue of benactyzine, a derivative of fluorencarbonic acid, on monoamine levels in brain structures were studied in male Wistar rats with experimental depression. Depressive state in rats was modeled by single injection of reserpine (4 mg/kg). The concentrations of norepinephrine (NE), dopamine (DA), serotonin (5-HT), and their metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanilic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in the hypothalamus and striatum were measured by HPLC. It was found that preliminary treatment (30 days) with the derivative of fluorencarbonic acid prevented a decrease in monoamine level in the hypothalamus (NE, 5-HT, and 5-HIAA) and striatum (DA, 5-HT, and 5-HIAA). The neurochemical shifts (correction of 5-HT deficiency and stabilization of DA and NE levels) correlated with the high antidepressant activity of this agent observed in Porsolt forced swimming test.

We studied radioprotective effects of a preparation based on yeast RNA and its influence on therapeutic efficiency of ionizing radiation against transplanted tumors. Parenteral administration of yeast RNA preparation to mice in a dose of 10 mg 1 h prior to exposure to ionizing γ-radiation (¹³⁷Cs) in a lethal dose (LD_80/30) increased 30-day survival by 66%; by day 80, 80% of animals survived (vs. 2.5% in the control). Whole-body exposure to ionizing γ-radiation in a dose of 7 Gy significantly increased the mean lifespan of mice with experimental lung metastases or intraperitoneally transplanted leukemia L-1210 by 42 and 20.8%, respectively. RNA preparation injected to the mice with tumors 1 h before irradiation did not affect the therapeutic efficiency of ionizing radiation or significantly potentiated it (in mice with transplanted leukemia L-1210). These results suggest that yeast RNA preparation protects healthy tissues during radiotherapy of malignant tumors.

Using immunofluorescence with specific antibodies, we analyzed DNA hydroxymethylation in uncultured cells from 25 human uterine leiomyomas considering the menstrual cycle phase during surgery and the presence of MED12 gene mutations. It was found that each tumor node had specific DNA hydroxymethylation level that did not depend on the presence of mutations in MED12 gene, but depended on the phase of menstrual cycle. The degree of DNA hydroxymethylation was significantly lower in cells of leiomyomas excised during the luteal phase compared to the follicular phase (p=0.0431). Hormonal status changing at various phases of menstrual cycle is a factor affecting DNA hydroxymethylation in leiomyoma cells.

The gene expression profiles of MDA-MB-231 cell line of breast cancer and xenografts derived from this tumor in murine model were analyzed using GeneChip Human Transcriptome array 2.0 platform (Affymetrix). A more than 1000-fold increase in the MIR1973 gene expression was observed in the xenografts compared to the original cell line. Real-time reverse transcription PCR showed that the content of mature hsa-miR-1973 microRNA encoded by this gene was elevated in the xenografts by more than 300 times. According to microarray analysis, none of hsa-miR-1973 target genes available in the databases changed the expression in the cell line and xenografts. A possible role of hsa-miR-1973 is reduction of apoptosis in the tumor.

We have discovered motives of short-chain epigenetically active peptides in some proteins of long-lived African mole rat Heterocephalus glaber. These epigenetic regulators are located in the protein structure between lysine and arginine residues, thus facilitating their release in limited proteolysis. Some of these epigenetic regulators are not found in the proteins of short-lived species — Norway rat Rattus norvegicus and house mouse Mus musculus.

Validation of the method for studies of glucokinase activators by the spectrophotometric method in an in vitro test system is carried out. The advantage of NAD coenzyme vs. thio-NAD is proven. Manifest activation of glucokinase by MBX-2982 compound (GPR119 agonist) in a wide range of concentrations is demonstrated experimentally.

In 60-day-old male rats after antenatal hypoxia, the body weight and the absolute weight of the cerebral hemispheres were significantly lower than in the progeny of intact animals. Analysis of brain sections stained with silver nitrate revealed reduced number of nucleoli in neocortical layer II and hippocampal CA1 neurons and smaller area of neuronal nuclei in neocortical layer V and total area of nucleoli in neurons of all studied zones. The animals demonstrated increased locomotor activity in the elevated plus-maze test. Chemiluminescent analysis of brain homogenates revealed the presence of oxidative stress at the organ level. Neonatal administration of non-opioid analog of leu-enkephalin (peptide NALE) after antenatal hypoxia normalized body weight, neutralized morphometric changes in the nucleoli and nuclei of neurons in the neocortex and hippocampus, and improved oxidative status of the brain. In 30- and 60-day-old male rats subjected to antenatal hypoxia and receiving peptide NALE during the neonatal period, behavioral responses were partially normalized. Non-opioid analog of leu-enkephalin can be a promising drug for correction of cerebral consequences of antenatal hypoxia.

Changes in the proteome of keratinocytes of immortalized HaCaT line exposed to cytotoxic substance Triton X-100 in concentrations of 12.5 and 25 μg/ml were studied by liquid chromatography combined with mass spectrometry. The appearance of proteins involved in the regulation of mitosis, RNA stability, and catabolic processes were detected; the number of apoptosis-associated proteins increased, while the number of proteins involved in differentiation and energy metabolism of keratinocytes decreased.

MicroRNA whose expression depends on the receptor status of breast cancer were selected using bioinformatic analysis. The expression of 9 microRNAs (16, 17, 21, 27, 125, 146, 155, 200a, and 221) was analyzed in 76 samples of breast cancer with various receptor phenotypes. The expression of microRNAs 155, 27, and 200a did not differ in various types of breast cancer. The data on positive correlation between the expression of microRNA-21 and microRNA-221 and negative receptor status of the tumor were confirmed. The expression of the tumor suppressing microRNA-125b decreased in samples of breast cancer expressing HER2 and ER and in triple negative breast cancer, which characterizes it as a universal marker of breast cancer. An increase in the expression of microRNA-16 was shown in samples of breast cancer expressing HER2 and ER. The expression of microRNA-17 decreased in triple negative breast cancer and increased in ER⁺, PR⁺, and HER⁺ types of breast cancer. MicroRNAs 16, 17, 21, 125b, 146b, and 221 can be promising markers for differential diagnostics of various phenotypes of breast cancer.

An ointment containing metabolites of Bacillus sp. microorganisms isolated from permafrost samples was applied onto the skin wound of BALB/c mice. Metabolites isolated during culturing of Bacillus sp. at 37°C produced a potent therapeutic effect and promoted wound epithelialization by 30% in comparison with the control (ointment base) and by 20% in comparison with Solcoseryl. Treatment with Bacillus sp. metabolites stimulated predominantly humoral immunity, reduced the time of wound contraction and the volume of scar tissue, and promoted complete hair recovery. These metabolites can be considered as modulators of the wound process with predominance of regeneration mechanisms.

Local application of the Dorogov’s antiseptic-stimulant onto the skin of 2-month-old male Sprague-Dawley rats in a low dose (0.5 g/kg/day) for 1 week increased motor and ultrasonic activity of experimental animals and the content of activated c-Fos⁺ neurons on the cingular, motor, insular, and pyriform cortex and in the striatum.

Morphological changes in the thymus and composition of its cells and peripheral blood lymphocytes were studied in experiments on C57Bl/6 mice with sodium dextran sulfate-induced acute ulcerative colitis. Severe acute ulcerative colitis in rats was accompanied by stage III-IV accidental involution of the thymus. This state was characterized by inversion of the layers, death of thymocytes, and increase in the number and area of thymic corpuscles from CK19⁺ epithelial cells. Flow cytofluorometry revealed an increase in the relative number of F4/80⁺ macrophages in the thymus stroma and CD4^—CD8^—CD45⁺CD11c⁺ dendritic cells and CD326⁺UEA⁺CD205^— epithelial cells in the medulla. By contrast, the count of CD326⁺UEA^—CD205⁺ epithelial cells remained unchanged in the cortex. Accidental involution of the thymus was accompanied by an increase in the number of apoptotic AnnV⁺PI^— cells, but decrease in the count of lymphocytes, CD3^—CD19⁺ B lymphocytes, CD3⁺CD8⁺ cytotoxic T lymphocytes, immature CD4⁺CD8⁺ lymphocytes, and CD3⁺CD4⁺ T helpers. The level of peripheral blood endotoxin in adult male C57Bl/6 mice with fibrinous ulcerative colitis was 10-fold lower than in the control. Moreover, we observed a decrease in the absolute number of leukocytes, lymphocytes, CD3⁺CD4⁺ T helpers, CD3⁺CD8⁺ cytotoxic T lymphocytes, CD4⁺CD25⁺FOXP3⁺ regulatory T lymphocytes, and CD3^—CD19⁺ B lymphocytes in the peripheral blood of animals.

Rats of the experimental group for 30 days received a ration in which the fat component (sunflower oil) was completely substituted with a lipid module enriched with docosahexaenoic acid and astaxanthin. Anxiety of animals in elevated plus-maze test and muscle tone in the grip strength test were evaluated before and after the experiment. Exhausting treadmill exercise was simulated after 30 days of feeding the lipid module. Modification of the lipid component of the diet (enrichment with docosahexaenoic acid and astaxanthin) reduced fatigue during exhausting physical exercise, increased muscle tone, and produced an anxiolytic effect. The results indicate the prospects of using the lipid module as a functional food ingredient in the composition of specialized food products.

On the page 553 Acknowledgements should be as follows: The study was supported by the Russian Science Foundation (grant 14-25-00024-P).