Vol 166, No 5 (2019)

Dysferlin protein plays a key role in the multimolecular complex responsible for the maintenance of sarcolemma integrity and skeletal muscle cell functioning. We studied the membrane distribution of nicotinic acetylcholine receptors and α2 isoform of Na,K-ATPase in motor endplates of m. soleus in dysferlin-deficient Bla/J mice (a dysferlinopathy model). Endplates of Bla/J mice were characterized by increased area (without changes in fragmentation degree) and reduced density of the membrane distribution of nicotinic acetylcholine receptors in comparison with the corresponding parameters in control С57Bl/6 mice. The density of the membrane distribution of α2 isoform of Na,K-ATPase was also reduced, but the level of the corresponding mRNA remained unchanged. It can be hypothesized that abnormal membrane localization of α2 isoform of Na,K-ATPase results from adaptive skeletal muscle remodeling under conditions of chronic motor dysfunction.

The cardioprotective and inotropic effects of standardized active natural substance based on high-molecular-weight compounds of humic origin were studied on the model of global ischemia (40 min) and reperfusion of isolated perfused rat heart. Preventive administration of the test substance (0.1 mg/ml) before ischemia/reperfusion modeling reduced reperfusion contracture and necrotic death of cardiomyocytes and promoted recovery of myocardial contractility. Blockade of NO synthase with L-NAME (100 μM) abolished the above effects of the test substance. It was hypothesized that NO synthase plays an important role in the development of the cardioprotective and inotropic effects of the test natural substance.

The study presents the results of behavioral phenotyping of rats with experimental chronic obstructive pulmonary disease (eCOPD) of different severity modeled by using a combination of inductors (purified papain and bacterial LPS) in increasing concentrations. Locomotor and exploratory activity, spatial memory, and anxiety were evaluated. In mild eCOPD, locomotor and exploratory activity increased, while other parameters did not differ from the control values. Rats with moderate eCOPD demonstrated moderately restricted locomotor function and increased anxiety. Severe eCOPD was associated with pronounced changes in all analyzed parameters. Correlation analysis revealed relationships between some behavioral parameters and blood oxygen saturation, inspiratory lung volume, and respiration rate. This indicates the role of respiratory failure in the pathogenesis of cognitive disorders.

The stages of stress reaction (anxiety and resistance) were reproduced on the model of stresssensitive hypertensive ISIAH rats. Analysis of the experimental data showed an increase in activity of the antioxidant defense system in ISIAH rats: total antioxidant activity of the blood and superoxide dismutase activity increased at the stage of anxiety and then decreased during the resistance stage.

Extracellular microRNA are one of the indicators of the functional state of cells. Culturing of Caco-2 cells under the conditions of microcirculation in a Homunculus microfluidic device allows better simulating natural environment of the body in comparison with static culturing. Impedance spectroscopy (BioClinicum Research Center) was used for non-invasive estimation of the monolayer quality and changes in the cell apical membrane due to the formation of microvilli. Under static conditions, Caco-2 cells release more microRNA from the apical membrane than under microcirculation conditions, while secretion of miR-320a, miR-24-3p, and miR-221-3p microRNA under static conditions can indicate stress of the cells and activation of inflammatory response. Under microcirculation conditions, the expression of laminin-α1 (LAMA1) was lower than under static conditions, which indicates deeper differentiation of cells.

For elucidation of the mechanisms of IgG binding with human plasminogen in prostate cancer patients, we propose an original ELISA on polystyrene plates with immobilized heavy and light plasminogen chains. The level of IgG bound to plasminogen heavy chain in the serum of prostate cancer patients significantly exceeded that in healthy volunteers. IgG treated with plasmin more actively (by more than 2 times) bound plasminogen heavy chain than intact IgG. These findings indicate the involvement of lysine-binding sites of plasminogen heavy chain in the interaction with the C-terminal lysine of IgG and their fragments. ROC analysis of ELISA data showed significant differences between serum samples from patients with prostate cancer and benign prostatic hyperplasia. It is hypothesized that IgG in the tumor region undergo proteolysis and their products appear in the circulation.

The antimetastatic activity of combined or individual administration of topotecan and tyrosyl-DNA phosphodiesterase 1 (Tdp1) inhibitor was examined under various administration schedules in mice with Lewis lung carcinoma modeled by intravenous injection of 200,000 clone/mouse. The greatest antimetastatic effect was observed after combined use of topotecan and Tdp1 inhibitor as documented by macroscopic study of the lungs that revealed the decreased metastatic scores by 76, 91, or 74% at the respective inhibitor doses of 2, 4, or 6 mg/mouse, respectively, in parallel with inhibition of metastasis up to 98% (at inhibitor dose of 4 mg/mouse) and morphological and morphometric analyses of the lung sections, which revealed elevation of metastasis growth delay index to 86 and 63% at the respective inhibitor doses of 4 and 6 mg/mouse, respectively. The combined administration of topotecan and Tdp1 inhibitor is viewed as the most effective way to eliminate the metastatic formations with possible restitution of focal lesions.

Superelastic titanium alloys (titanium-niobium-zirconium and titanium-niobium-tantalum) are considered to be the more advantageous choice for dental implants than titanium alloys due to their physico-mechanical properties close to those of the bone tissue. Morphological studies of the biocompatibility of these alloys in comparison with titanium were carried out in vivo. Scanning electron microscopy and microprobe elemental analysis of the tissue along the interface between the bone and titanium/superelastic titanium alloys showed similar morphology and elemental composition both on days 30 (poorly mineralized connective tissue was detected in sites of contact with titanium alloy samples) and 90 after surgery (the surface of the titanium alloy samples was covered with mineralized tissue similar by its composition to the surrounding bone).

The effects of heterotransplantation on bone marrow structures were studied in experimental male mice. Suspension of the bone marrow from feline femur (1 ml bone marrow diluted in isotonic saline, 1:2) was injected into the caudal vein. Heterotransplantation led to an increase in the level of serotonin involved in cell differentiation. In 2 days, the counts of all cells except erythroid cells decreased. Immunohistochemical analysis of Ki-67 marker within 40 min after transplantation showed a significant increase of cell proliferative activity in comparison with that in intact mice. At later terms, the expression of Ki-67 in bone marrow cells decreased, while the expression of apoptosis regulator P-53 increased, which was associated with the presence of numerous dead cells.

We studied the effects of extremely low-frequency electromagnetic field on the ovaries in rats. The female rats were exposed to a 30 Hz sinusoidal magnetic field of 4 kA/m for 2 h per day for a period of 10 weeks, including the period of embryonic development. After the exposure, the duration of the estrous cycle and serum levels of luteinizing hormone, follicle stimulating hormone, progesterone, and estradiol E2 were measured in different phases of the estrous cycle and morphological changes in the ovaries were evaluated. Lower levels of follicle stimulating hormone in the proestrus and progesterone in the estrus phase were found; in the ovaries, the content of primordial follicles was lower than in the control. The exposure to electromagnetic field in the selected mode caused no significant defects in the structure and function of rat ovaries.

The contribution of prenatal hypoxic damage to the CNS to the formation of high sensitivity of the body to lead acetate was studied. Prenatal fetal hypoxia was modeled by the administration of sodium nitrite in doses of 5, 25, and 50 mg/kg to pregnant female rats. Cognitive capacities of mature offspring were evaluated in the radial maze test and Morris water maze test. After attaining learning criterion in the radial maze, lead acetate in a dose of 80 mg/kg was added to the drinking water of all animals over 2 weeks. Testing was performed during the exposure to the agent until disruption of the conditioned behavior. It was found that severe prenatal hypoxia (induced by the administration of 50 mg/kg sodium nitrite) impaired spatial memory, increased latency of funding the platform in Morris water maze test, and serves as a factor contributing to earlier manifestations of the neurotoxic effects of lead acetate.

Over many years, tick-borne infections remain one of the most serious threats to human health worldwide. The immune response to these infections in a human after confirmed bite by an infected carrier at the early stages of infection in the absence of clinical symptoms can be the first indicator of the presence of the infectious agent in the body. During viral infection, the concentration of IL-1α, IL-8, IL-10, IL-17A, and IFNγ increases; superoxide dismutase also increases, in contrast to bacterial infections. A slight decrease in the concentration is observed only for receptor antagonist IL-1Ra. During the infection caused by bacterial pathogens, very similar profiles of the innate human immune response are observed: activation of IL-1α, IL-8, and IFNα and suppression of superoxide dismutase, IL-1Ra, and IL-17A production. It has been demonstrated, that the immune response is triggered immediately after infection, and changes in the concentration of the main cytokines in the blood plasma can be detected as early as on days 2-5 after tick bite. These results can be useful in developing new methods of emergency diagnosis and prevention of tick-borne infections.

We compared three cold-adapted live attenuated influenza vaccine strains prepared by reverse genetics methods on the basis of master donor virus A/Leningrad/134/17/57 and influenza H7N9 strains A/Anhui/1/2013 and A/Shanghai/1/2013. Two strains based on A/Anhui/1/2013 differed by amino acid positions 123 and 149 in HA1 (123N/149N; 123D/149D). All strains efficiently replicated in developing chicken embryos; A/Shanghai/1/2013-based strain and A/Anhui/1/2013-123N/149N variant were characterized by reduced replication in MDCK cells. Strains based on A/Anhui/1/2013 virus agglutinated erythrocytes with α2,3- and α2,6-linked sialic acid residues, whereas strain A/Shanghai/1/2013 only α2,3. In experiments with BALB/c mice, Anhui-123D/149D strain was most immunogenic and induced high crossreactive humoral immune response, therefore it can be recommended as the model virus for the construction of recombinant vector vaccines based on live attenuated influenza vaccine.

Metastatic cascade is associated with the process of epithelial-mesenchymal transition accompanied by changes in cell proliferation, migration, adhesion, and invasiveness mediated by the insulin-like growth factor (IGF) signal pathway. IGFBP6 protein binds IGF and prevents its interaction with receptors. IGFBP6 gene knockdown through RNA-interference inhibits cell migration and increased the rate of proliferation of breast cancer MDA-MB-231 cells. IGFBP6 knockdown cells are characterized by increased expression of MIR100 and MIRLET7A2 genes encoding hsa-miR-100-3p, hsa-miR-100-5p, hsa-let-7a-5p, and hsa-let-7a-2-3p miRNA. The target genes of these microRNAs are IGF2, IGF1R, INSR, and CCND1 associated with IGF signaling pathway and proliferative and migratory activity during the metastatic cascade. A significant decrease in the expression of INSR and CCND1 genes was demonstrated by PCR and microarray analysis.

ROS are important intracellular messengers; their ambiguous role in malignant processes was demonstrated in many studies. The effects of a synthetic phenolic antioxidant sodium 3-(3’-tert-butyl-4’-hydroxyphenyl)propyl thiosulfonate sodium (TS-13) on the tumor growth and oncolytic properties of doxorubicin were studied in the experimental model of Lewis lung carcinoma in mice. In mice receiving TS-13 with drinking water (100 mg/kg), suppression of tumor growth by 32.3% was observed on day 21 after inoculation of Lewis lung carcinoma cells. Two-fold intraperitoneal injections of doxorubicin in a cumulative dose of 8 mg/kg were followed by inhibition of tumor growth by 49.5%. Combined treatment with TS-13 and doxorubicin suppressed the tumor growth by 55.4%. In contrast to doxorubicin, TS-13 inhibited NO generation by peritoneal macrophages. The results show the prospect of studying TS-13 in the context of overcoming drug-resistance of tumors.

We examined the efficacy of embryoid bodies from 6-day induced pluripotent stem cells an in vivo sepsis model. Injection of embryoid bodies to septic mice improved the condition of their lungs and significantly increased their survival rate. Although embryoid bodies secretedsphingosine-1-phosphate in vitro, its serum levels in mouse plasma were significantly reduced compared to that in the control (untreated mice receiving PBS). Low concentrations of sphingosine-1-phosphate protected endothelial cells, while high concentrations disrupted endothelial barrier integrity. Therefore, exogenous sphingosine-1-phosphate secreted by embryoid bodies during early stage of sepsis might down regulate endogenous production of sphingosine-1-phosphate. Inhibition of excessive sphingosine-1-phosphate release protects against endothelial injury and suppresses a vicious cycle of inflammatory reactions. The obtained results open new prospects in induced pluripotent stem cells-based therapy for sepsis.

The expression of Aβ42, and τ-protein, and p16 and p53 proteins was analyzed in the buccal epithelium of elderly and senile patients with Alzheimer’s disease. We revealed enhanced synthesis of Alzheimer’s disease markers Aβ42 (by 15-30 times) and τ-protein (by 5 times) in comparison with the corresponding values in people without neurodegenerative pathology of the same age groups. In addition, increased synthesis of proteins of cell aging and apoptosis p16 (by 6-10 times) and p53 (by 2-3 times) was observed in patients in comparison with age-matched persons without neuropathology. These data suggest that complex analysis of the expression of Aβ42, τ-protein, p16, and p53 in the buccal epithelium is a promising method for in vivo diagnosis of Alzheimer’s disease and assessment of the rate of aging during the development of this pathology.

The structure of the testicles was studied in adult rats in 120 days after a single intravenous injection of chitosan-modified (magnetic nanospheres) and lipid-modified (magnetoliposomes) nanosized magnetite particles. Perls histochemical reaction detected in the testicular interstitial connective tissue the cells which absorbed and accumulated magnetite nanoparticles. The dynamics of spermatogenesis index and the count of Perls⁺ cells in the rat testicles were traced throughout the experiment. The studied modified nanosized magnetite particles did not penetrate through the blood—testicle barrier in rats.