Vol 163, No 5 (2017)
- Year: 2017
- Articles: 31
- URL: https://journals.rcsi.science/0007-4888/issue/view/14815
Physiology
Kinetics of Mechanical Stretch-Induced Nitric Oxide Production in Rat Ventricular Cardiac Myocytes
Abstract
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.
Article
Diadenosine Polyphosphates Suppress the Effects of Sympathetic Nerve Stimulation in Rabbit Heart Pacemaker
Abstract
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.
Element Status of Students with Different Levels of Adaptation
Abstract
The element status was studied in students with different levels of adaptation determined by the parameters of cardiointervalography. The content of chemical elements in the hair was measured by atomic emission and mass spectrometry. In students whose autonomic status was characterized by sympathicotonia, the level of cobalt in the hair was significantly higher, while the levels of manganese and magnesium were lower than normal. The content of selenium in the hair was 2.3 times lower in the study group in comparison with the median level in Russia. The content of toxic elements did not exceed the normal. Significant positive correlations between hair content of magnesium and calcium and between potassium and sodium were revealed.
Effect of Electroconvulsive Therapy on Cognitive Functions of Rats with Depression-Like Disorders Induced by Ultrasound Exposure
Abstract
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.
Effects of Physiological Nitric Oxide Donor on Oxidative Metabolism in Rat Blood
Abstract
The effects of exogenous dinitrosyl iron complexes with glutathione ligands on the parameters of oxidative metabolism in the rat blood are studied. The intensity of LPO, total antioxidant activity, and MDA level in the plasma are compared in rats receiving intraperitoneal injections of saline without and with dinitrosyl iron complexes in various concentrations (0.15, 0.30, 0.45, and 0.60 mM). Glutathione—containing dinitrosyl iron complexes are characterized by antioxidant effect that non-linearly depended of the dose with optimum at 0.30-0.45 mM.
Activities of Proline-Specific Proteinases in the Serum and Cerebrospinal Fluid of Rats with the Fetal Valproate Syndrome
Abstract
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.
Adipokine and Cytokine Profiles of Epicardial and Subcutaneous Adipose Tissue in Patients with Coronary Heart Disease
Abstract
The content of adipokines, pro- and anti-inflammatory cytokines were studied in adipocytes isolated from epicardial and subcutaneous adipose tissue of 24 coronary heart disease patients. The content of leptin and soluble leptin receptor in adipocytes of epicardial adipose tissue was higher by 28.6 and 56.9% and the level of adiponectin was lower by 33% than in adipocytes of the subcutaneous fat. In culture of epicardial adipocytes, the levels of proinflammatory cytokines TNF-α and IL-1 were higher. Subcutaneous adipose tissue adipocytes were characterized by higher levels of anti-inflammatory cytokines IL-10 and FGF-β. In epicardial adipocytes of coronary heart disease patients, the concentrations of leptin, TNF-α, and IL-1 were higher, while the levels of defense regulatory molecules (adiponectin, IL-10, and FGF-β) were lower than in subcutaneous adipocytes.
Rhythmoinotropic Response of Papillary Muscles in Rats with Different Severity of Postinfarction Cardiosclerosis
Abstract
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.
Changes in Sympathetic Innervation of the Heart in Rats with Experimental Myocardial Infarction. Effect of Semax
Abstract
The effect of peptide Semax on remodeling of cardiac sympathetic innervation was examined in rats with experimental myocardial infarction. In 28 days after ischemia/reperfusion injury, Semax diminished the growth of sympathetic innervation of ventricular septum, although it produced no effect on the density of β1 and β2 adrenoceptors.
Relationship between the Contents of Cyclins, Cyclin-Dependent Kinases, and Their Inhibitors in Whole Blood Mononuclear Leukocytes during the Postclinical Stage of Community-Acquired Pneumonia under the Influence of 1-GHz Microwaves
Abstract
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.
Alcoholic Cardiomyopathy: Translation Model
Abstract
We developed a translation model of alcoholic cardiomyopathy in rats. By the end of forced alcoholization (the rats received 10% ethanol solution as the only source of fluid for 24 weeks; mean daily ethanol consumption was 5.0-6.5 g/kg), the rats developed dilated heart failure. Echocardiography and morphometric study of the myocardium revealed a decrease in inotropic function of the heart and dilatation of the right and left ventricles. Fatty degeneration of the myocardium (pathognomonic sign of alcoholic cardiomyopathy) and decrease in electrical stability of cardiomyocytes reliably reproduce the clinical pattern of alcoholic cardiomyopathy.
Effects of Fluorencarbonic Acid Derivative on the Levels of Monoamines and Their Metabolites in Brain Structures of Rats with Modeled Depression-Like State
Abstract
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.
Effects of Pegylated Glucagon-Like Peptide-1 Analogue in C57Bl/6 Mice under Optimal Conditions and During Streptozotocin-Induced Diabetes
Abstract
Biological activity of a new pegylated form of an of glucagon-like peptide-1 (GLP-1) analogue pegGLP-1 was studied in C57Bl/6 mice under normal conditions and during modeling of streptozotocin-induced type I diabetes mellitus. pegGLP-1 differs from GLP-1 (7-37) by polyethylene glycol residue covalently bound to His7, Lys26, and Lys34 of the GLP-1 molecule. It was shown that single intragastrical administration of pegGLP-1 induced an increase in GLP-1 level in blood serum of healthy mice. The maximum level of this parameter was observed in 4-8 h. pegGLP-1 elimination half-time was 8.5 h and mean retention time was 15 h. Administration of pegGLP-1 to animals with modeled type I diabetes mellitus was followed by an increase in the levels of GLP-1 and insulin in blood serum, produced a hypoglycemic effect, and improved the parameters of glucose-tolerance test. Biological activity of pegGLP-1 was higher than activity of GLP-1.
Experimental Study of Yeast RNA Preparation as a Possible Radioprotective Agent for Radiotherapy of Malignant Tumors
Abstract
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 (LD80/30) 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.
Role of Glutathione-S-Transferase Family Genes in Male Infertility
Abstract
Polymorphisms of xenobiotic detoxification genes GSTT1 and GSTM1 and activity of glutathione system enzymes were studied in men with infertility. The frequency of deletion variant of GSTT1 gene in men with infertility was by 2 times higher than in fertile men. Deletion variant of GSTM1 gene was 1.4-fold more frequent in infertile men than in fertile men. Complete deletion of two genes was found in 19% men with infertility and only in 6% fertile men. The balance of activity of glutathione system enzymes essential for the effective detoxification of exogenous xenobiotics and toxic endogenous metabolites was impaired in infertile carriers of deletion variants of genes. Our results suggest that adaptation mechanisms are disordered in infertile men.
Differential DNA Hydroxymethylation in Human Uterine Leiomyoma Cells Depending on the Phase of Menstrual Cycle and Presence of MED12 Gene Mutations
Abstract
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.
Polymorphism of Matrix Metalloproteinases Genes MMP1, MMP2, MMP3, and MMP7 and the Risk of Varicose Veins of Lower Extremities
Abstract
We studied the effects of single nucleotide polymorphisms in the promoter regions of matrix metalloproteinase genes rs1799750 (-1607dupG) MMP1, rs243865 (C-1306T) MMP2, rs3025058 (-1171dupA) MMP3, and rs11568818 (A-181G) MMP7 on the risk of varicose vein of the lower extremities in ethnical Russians, residents of the Russian Federation. We genotyped 536 patients with this pathology and 273 healthy participants without history of chronic venous disease. Association was examined using logistic regression analysis. None of the studied polymorphisms showed statistically significant association with the risk of varicose veins of the lower extremities. Our results provide evidence that these polymorphisms are not involved in the pathogenesis of varicose veins and cannot serve as markers of predisposition to this pathology.
hsa-miR-1973 MicroRNA is Significantly and Differentially Expressed in MDA-MB-231 Cells of Breast Adenocarcinoma and Xenografts Derived from the Tumor
Abstract
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.
Matrixins in the Salivary Fluid of Patients with Tumors of the Maxillofacial Region during Orthopedic Rehabilitation with Different Prosthetic Structures
Abstract
Dental and immunological features of the influence of various prosthetic structures of orthopedic prostheses on tissues and organs of the maxillofacial region were evaluated by the parameters of expression of oral fluid biomarkers. Healthy people without tumor and somatic diseases and patients with neoplasms of maxillofacial area in need of dental rehabilitation were examined before and in 2 weeks and 3 months after treatment. Certain regularities in the reaction of biomarkers to orthopedic prostheses were observed: a decrease in activity of MMP-2 and MMP-8 and their inhibitors or an increase in MMP-9; an increase in activity of biomarkers at early terms and a decrease in delayed terms after prosthetics.
Peptides (Epigenetic Regulators) in the Structure of Rodents with a Long and Short Lifespan
Abstract
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.
Relationship between Hypoxic Resistance and the Phase of 4-Day Corticosterone Biorhythm in Adult Male Rats
Abstract
The relationship between the phase of 4-day serum corticosteroid biorhythm and resistance to acute hypobaric hypoxia was studied in male rats. Single evaluations of hypoxic resistance of Wistar rats during the same time of the day have shown that the lifespan of animals is significantly longer during the 4-day biorhythm acrophase than during the bathyphase. Daily testing for 12 days has detected a 4-day rhythm of hypoxic resistance, synphasic with corticosterone biorhythm, irrespective of the wave-like course of the adaptation process phase from the beginning of daily testing and hypoxic resistance. Experiments on Sprague-Dawley rats have shown that animals highly resistant and medium resistant to hypoxia during the infradian biorhythm acrophase become medium resistant and poorly resistant during the bathyphase. In order to detect the animals with the least hypoxic resistance in the population, the studies should be carried out during the 4-day infradian biorhythm acrophase, while detection of the most resistant animals should be carried out during the bathyphase.
Effect of GRP119 Receptor Agonist, Compound MBX-2982, on Activity of Human Glucokinase
Abstract
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.
General Pathology and Pathophysiology
Delayed Effects of Neonatal Administration of Non-Opioid Analog of Leu-Enkephalin on Cerebral Consequences of Antenal Hypoxia
Abstract
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.
Biophysics and Biochemistry
Changes in the Proteome of HaCaT Keratinocytes Induced by Cytotoxic Substance Triton X-100
Abstract
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.
Oncology
Search of MicroRNAs Regulating the Receptor Status of Breast Cancer In Silico and Experimental Confirmation of Their Expression in Tumors
Abstract
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.
Immunology and Microbiology
Reparation and Immunomodulating Properties of Bacillus sp. Metabolites from Permafrost
Abstract
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.
Experimental Methods for Clinical Practice
Effect of Skin Application of Dorogov’s Antiseptic-Stimulant on Behavioral Reactions in Rats
Abstract
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.
Morphology and Pathomorphology
Morphological Changes in the Thymus, Composition of Its Cells, and Subpopulations of Peripheral Blood Lymphocytes during Experimental Acute Ulcerative Colitis
Abstract
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.
Methods
Experimental Evaluation of the Efficiency of Lipid Module Enriched with Docosahexaenoic Acid and Astaxantin
Abstract
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.