Том 161, № 4 (2016)

We studied pro-cognitive effect of two heterocyclic low-molecular-weight compounds that serve as non-peptide analogues of soluble fragment of amyloid peptide precursor (sAPP). Intracerebroventricular and systemic administration of peptide mimetics P2 and P5 improved weak memory on the model of passive avoidance in chicks and in the object location task in mice. Both compounds were effective if administered close to the moment of training or 4 h after it. The time windows and dose range for the pro-cognitive effects of the mimetics were similar to those observed in previous studies with sAPP peptide fragments.

Al³⁺, Fe³⁺, and Zn²⁺ ions can disturb microtubule assembly from tubulin and microtubuleassociated proteins in rat brain. The main structural forms of these microtubules are rings and tangled bundles. These structures are formed only in the presence of Al³⁺ and Fe³⁺ ions. Therefore, Zn²⁺ ions can be excluded from possible causes of structural abnormalities in microtubules during Alzheimer’s disease. Al³⁺ ions are the most probable etiological cause of Alzheimer’s disease. The concentration of Al³⁺ ions affecting the structure of microtubules is one order of magnitude lower than that of Fe³⁺ ions (10 and 100 μM, respectively), which corresponds to their brain concentration reported in Alzheimer’s disease.

Post-traumatic stress disorder was imitated in rats with long and short hexenal sleep by exposure to cat odor. Rats with long hexenal sleep demonstrated the highest sensitivity to posttraumatic stress disorders and developed anxiety and depressive disorders. The duration of hexenal sleep correlated with changes in markers of post-traumatic stress disorder, e.g. activity of 11β-hydroxysteroid dehydrogenase-2 in the liver of non-stressed animals and serotonin and monoamine oxidase A activity in the brain of stressed animals.

Rats were subjected to surfactant-BL inhalations at the early and late phases of bleomycininduced alveolitis. In both regimens, the drug reduced the severity of inflammation. In the acute phase of alveolitis, the therapeutic effect of inhalation was accompanied by activation of the synthesis of fine lose collagen fibrils. In the late phase of alveolitis, inhalation of surfactant-BL thickened the fibrils and diminished their population in alveolar walls.

We studied the expression of chaperone GRP-78 and transcription factor NF-kB during the development of ischemic tolerance of the brain after combined and isolated exposure to hypoxia and hypercapnia. Combined exposure to hypoxia and hypercapnia maximally increased the expression of chaperone GRP-78 and transcription factor NF-kB, while the formation of ischemia-induced tolerance under conditions of hypercapnic hypoxia can be associated with activation of adaptive stress mechanisms in the endoplasmic reticulum. Under these conditions, hypercapnia in combination with hypoxia is a priority factor for activation of GRP-78 and transcription factor NF-kB.

The influence of Opisthorchis felineus invasion on the development of pathological changes in the hepatobiliary system was studied in 120 golden hamsters in a long-term experiment (42 weeks) after single infection per os in the dose of 50 metacercariae per animal. The animals were sacrificed on weeks 4, 8, 12, 16, 28 and 42. Chronic experimental infestation with O. felineus triggered a cascade of morphogenetic processes in both extrahepatic and intrahepatic biliary systems. At the early stages of the experiment, polyps and strictures of bile ducts were formed in the lobar bile ducts; in portal tracts, hyperplasia and adenomatous transformation of the newly formed epithelial structures were observed. At the later stages, third-degree biliary intraepithelial neoplasia developed in the lobar bile ducts; in the intrahepatic bile ducts, increased epitheliocyte hyperplasia and invasive growth of cell cords were observed, that impaired tissue architectonics. Progressing cell atypia can be classified as cholangiocellular cancer.

Myeloperoxidase, heme enzyme of azurophilic granules in neutrophils, is released into the extracellular space in the inflammation foci. In neutrophils, it stimulates a dose-dependent release of lactoferrin (a protein of specific granules), lysozyme (a protein of specific and azurophilic granules), and elastase (a protein of azurophilic granules). 4-Aminobenzoic acid hydrazide, a potent inhibitor of peroxidase activity of myeloperoxidase, produced no effect on neutrophil degranulation. Using signal transduction inhibitors (genistein, methoxyverapamil, wortmannin, and NiCl₂), we demonstrated that myeloperoxidase-induced degranulation of neutrophils resulted from enzyme interaction with the plasma membrane and depends on activation of tyrosine kinases, phosphatidylinositol 3-kinases (PI3K), and calcium signaling. Myeloperoxidase modified by oxidative/halogenation stress (chlorinated and monomeric forms of the enzyme) lost the potency to activate neutrophil degranulation.

The specific features of alcohol behavior were studied in MR and MNRA rats that exhibit an opposite reaction to emotional stress. We evaluated the effect of a dipeptide anxiolytic GB-115 (N-phenyl-hexanoyl-glycyl-L-tryptophan amide, neuropeptide cholecystokinin-4 analogue with antagonistic activity) on alcohol motivation in rats, which was formed over 12 months. High-emotionality MR rats were more sensitive to the anxiolytic effect of ethanol in the conflict situation test than low-emotionality MNRA rats. MNRA rats consumed a greater amount of ethanol under a free-choice condition with 15% ethanol solution and water (as in comparison with MR rats). However, the behavior of MR rats was transformed due to a significant increase in alcohol motivation from the 5th month of long-term free access to ethanol. An anxiolytic GB-115 (0.025 mg/kg intraperitoneally for 14 days) with selective activity in high-emotionality rats was shown to reduce significantly the average daily consumption and alcohol-deprivation effect in MR rats, but did not modulate ethanol addiction in MNRA rats.

Stem and progenitor cells were studied on mouse model of testicular ischemia. Testicular ischemia led to a decrease in free testosterone concentration. Hemodynamic changes, interstitial edema, and destruction of spermatogenic epithelium, Leydig, and Sertoli cells were observed in the testicular tissue. Accumulation of degenerative germ cells was accompanied by reduction in the count of spermatogonial stem cells with immunophenotype CD117^–CD29⁺CD90⁺ and CD117⁺CD29⁺CD90⁺. Simultaneously with pathomorphological changes in the testes and suppression of spermatogenesis, ischemia reduced the count of hematopoietic progenitor cells, hematopoietic stem cells with immunophenotype Lin^–CD117⁺Sca-1⁺c-kit⁺CD34⁺ and Lin^–CD117⁺Sca-1⁺c-kit⁺CD34^–, and multipotent mesenchymal stromal cells (CD45^–CD31^– CD90⁺CD106⁺) in the testicular tissue. The population of CD45^–CD31⁺-endothelial cells in ischemic testicular tissue increased.

Blood levels of 8-hydroxy-2’-deoxyguanosine (8-OHdG) were measured by enzyme immunoassay after overnight fasting in untreated breast cancer and endometrial cancer patients (N=170) of mainly postmenopausal age with and without type 2 diabetes mellitus. The concentrations of 8-OHdG in patients with breast cancer were higher than in patients with endometrial cancer and in patients with breast cancer and diabetes in comparison with patients with breast cancer without diabetes. No correlations of blood 8-OHdG levels with glycemia, age, and clinical stage of disease were detected. In cancer patients with diabetes, the concentration of 8-OHdG increases proportionally to the increase in body mass index, though this does not lead to disappearance of the above differences between patients with breast cancer and endometrial cancer by the level of 8-OHdG. The causes of the trend to a less favorable course of tumor process in patients with breast cancer and diabetes in comparison with endometrial cancer and diabetes deserve further studies.

Tripeptide glycyl-prolyl-proline (PGP), a regulatory peptide of the glyproline family, possesses a pronounced anti-inflammatory effect primarily due to its ability to prevent secretion of the proinflammatory mediator histamine by rat peritoneal mast cells. Activation of mast cell with synacthen (ACTH1-24) and substance 48/80 leads to an increase in intracellular calcium concentration. Pretreatment of mast cells with PGP prevented calcium entry into the cytoplasm from both intercellular space and intracellular stores. Acetylated peptide (N-AcPGP) produced a similar effect on histamine release and intracellular calcium content in mast cells activated with synacthen. These findings indicate that both forms of the peptide can stabilize mast cells and prevent intracellular calcium increase.

Effect of the dipeptidyl peptidase-4 inhibitor linagliptin on structural manifestations of diabetic nephropathy was studied in BKS.Cg-Dock7m+/+Leprdb/J mice (experimental model of type 2 diabetes mellitus). Linagliptin (10 mg/kg per day) or vehicle was administered by gavage over 8 weeks. Mesangial expansion, thickening of the basement membrane in glomerular capillaries and proximal tubules, and retraction of cytopodia were less pronounced in mice receiving linagliptin. The protective effect of linagliptin on the kidney structure was not associated with its hypoglycemic action.

We analyzed the interactions between peripheral blood lymphocytes from heterologous donors with mesenchymal stem cells obtained from the tooth pulp and trophoblast. In mixed cultures, proliferation of both lymphocytes and mesenchymal stem cells was suppressed. Similar suppressive effects were observed in lymphocyte cultures mixed with epithelial cells (hepatocytes HeG2 and renal epithelial cells HEK293). This suppression can be determined by impairment of normal adhesion contacts between cells of different origin.

The immunoepitope database was used for analysis of experimentally detected epitopes of the respiratory syncytial virus (RSV) proteins and for selection of the epitope combinations for subsequent designing of recombinant vectored anti-RSV vaccines based on attenuated influenza viruses. Three cassettes containing the most promising B- and T-cell RSV epitopes were selected: peptide F (243-294) supporting the formation of humoral immunity in animals; fragment M2-1 (70-101+114-146) containing two MHC I epitopes (82-90 and 127-135); and MHC II-epitope (51-66). The selected constructions contained no neoepitopes causing undesirable effects of vaccination, such as immunotolerance or autoimmunity.

Biocompatibility of a new tracheal matrix is studied. The new matrix is based on polymeric ultra-fiber material colonized by mesenchymal multipotent stromal cells. The experiments demonstrate cytoconductivity of the synthetic matrices and no signs of their degradation within 2 months after their implantation to recipient mice. These data suggest further studies of the synthetic tracheal matrices on large laboratory animals.

The expression of molecular markers characterizing activity of the tumor process and metastases (proliferation marker Ki-67, angiogenesis marker CD34, and lymphangiogenesis markers podoplanin and LYVE-1) was assessed by immunohictochemical method in the primary tumor specimens collected during surgery for cutaneous melanoma (40 patients). Proliferative activity of the tumor tissue and volume density of peritumoral blood and lymph vessels increased with increasing tumor malignancy, which could indicate the risk of metastases.

Positive reaction of the bronchi to distilled water inhalation in asthmatics is associated with significant stimulation of the respiratory epithelium desquamation against the background of increased content of eosinophilic and neutrophilic leukocytes in induced sputum, predomination of eosinophil and neutrophil cytolysis, and lower activity of myeloperoxidase in leukocyte granules (in comparison with the parameter in patients with a negative response to bronchostimulation). Enhanced cytolysis and destruction of leukocytes and high myeloperoxidase concentration in the extracellular space are essential for the development of bronchial hyperresponsiveness to hypoosmotic stimulus in asthma.

Morphofunctional disorders in unicellular aquatic protozoa – Spirostomum ambiguum infusorians after 30-, 60-, and 360-min exposure in electromagnetic field at a radiation frequency of 1 GHz and energy flow density of 50 μW/cm² were analyzed by intravital computer morphometry. Significant disorders in morphometric values correlated with low mobility of the protozoa. The results suggested the use of intravital computer morphometry on the protozoa for early diagnosis of radiation-induced effects of the mobile communication electromagnetic field, for example, low mobility of spermatozoa.

We developed and adapted a technology for preparation of articular cartilage specimens for scanning electron microscopy. The method includes prefixation processing, fixation, washing, and dehydration of articular cartilage specimens with subsequent treatment in camphene and air-drying. The technological result consists in prevention of deformation of the articular cartilage structures. The method is simpler and cheaper than the known technologies.

This concise review provides an assessment of one of the most conceptually and practically important properties of mesenchymal stromal cells, their ability to modulate immune responses, including underlying cellular and molecular mechanisms and prospects of clinical application in the treatment of autoimmune and other immunological disorders.

We studied the interaction of neural stem cells and dental pulp-derived mesenchymal stem cells with lymphocytes from autologous and heterologous donors. Flow cytometry analysis with the use of CFSE-labeled lymphocytes demonstrated an increase in the content of proliferating CD8, CD16 and CD56 cells, but not CD4 cells in cultures of HLA-DR-negative mesenchymal stromal cells from the dental pulp co-cultured with lymphocytes. In neural cultures expressing HLA-DR, all subpopulations of T cells and NK cells were activated. No differences between the autologous and heterologous cultures were revealed.

We studied the structure of porous permeable titanium nickelide used as the scaffold. In vitro population of the porous scaffold with multipotent mesenchymal stem bone marrow cells on days 7, 14, 21, and 28 was analyzed by scanning electron microscopy. Stage-by-stage histogenesis of the tissues formed from the bone marrow cells in the titanium nickelide scaffold in vivo is described in detail. Using mesenchymal stem cells, we demonstrated that porous permeable titanium nickelide scaffolds are unique incubators for cell cultures applicable for tissue engineering.

Long-term administration of simvastatin to rats, irrespective of the baseline cholesterol levels, induced biochemical changes in erythrocytes attesting to hypoxic damage (accumulation of lactate and 2,3-diphosphoglycerate), disturbances in ATP-dependent mechanisms of ion homeostasis regulation (decrease in total ATPase and Ca²⁺-ATPase activities), and antioxidant enzymes system imbalance. These changes can be considered as a sensitive indicator and molecular basis of cell damage during long-term administration of statins.

Cell cultures isolated from endometriosis lesions by enzymatic dissociation consisted of fibroblast-like cells expressing CD90, CD73, and CD105; cell viability in these cultures was >90%, but this parameter decreased by passage 3. Zero passage cultures contained 10-25% epithelial cells expressing cytokeratin-7, but by passage 2, the cultures became more homogeneous and epithelial cells disappeared. The proportion of proliferating cells and population doubling level increased from passage 1 to passage 3. The cultures from the endometrium were induced to adipogenic and osteogenic differentiation in vitro. The cultures derived from ectopic endometrium have properties of multipotent mesenchymal stromal cells that exhibited in vitro similarities and differences from cell cultures from eutopic endometrium, which allows using this cell model for the search and testing of new drugs and technologies aimed at suppression of the growth and spread of endometriosis lesions.