Hypolipidemic effect of mannans from C. albicans serotypes a and B in acute hyperlipidemia in mice.

Mannans, which are biological macromolecules of polysaccharide origin and function as immunomodulators, have been shown to stimulate macrophages in vivo by interaction with the mannose receptor. Thus, they can be used to stimulate macrophages in order to effectively remove circulating atherogenic lipoproteins. Our primary aim was to evaluate the hypolipidemic potential of mannans from C. albicans serotype A (mannan A) and serotype B (mannan B) in a murine model of hyperlipidemia. Mannan A and mannan B were shown to significantly (p<0.05) stimulate both the proliferation (p <0.05) and nitric oxide production of murine peritoneal macrophages in vitro. Pre-treatment of CBA/Lac mice with mannan A prior to induction of hyperlipidemia significantly (p<0.001) reduced serum atherogenic LDL-cholesterol, total cholesterol, and triglycerides. Mannan B exhibited a similar, but more potent, hypolipidemic effect. Electron microscopic analysis of liver revealed a significant (p<0.001) decrease in the volume of lipid droplets when hyperlipidemic mice were pretreated by both mannans. In conclusion, our findings would suggest that both polysaccharide-based biological macromolecules evaluated in the present study, specifically, the natural immunomodulators (mannans A and B), appeared to function as effective lipid-lowering macromolecules, which could potentially serve as adjunct therapy to more conventional hypolipidemic medications such as a statin drug.

Cystatin C as a Marker of Progressing Cardiovascular Events during Coronary Heart Disease.

The role of cystatin C, an inhibitor of cysteine proteases, as an alternative and potent predictor of acute cardiovascular events in coronary heart disease (CHD) patients was examined and compared to that of other markers of cardiorenal abnormalities. The patients with CHD demonstrated elevated serum cystatin C, especially in cases with serious risk of cardiovascular complications. In comparison with other indicators of cardiorenal dysfunction, cystatin C can be viewed as an alternative predictor of cardiovascular complications, although its sensitivity is inferior to that of high-sensitivity C-reactive protein and natriuretic peptide.

Effects of Anti-CD206 Antibodies on Macrophage Functions in Male CBF1 Mice with Lipidemia.

The effects of anti-CD208 antibodies (mannose receptor) on functional characteristics of peritoneal macrophages were studied in intact mice and mice with lipidemia induced by poloxamer-407. Lipidemia was associated with suppression of phagocytosis and increase in spontaneous proliferative potential and NO production by macrophages. Anti-CD206 antibodies suppressed NO production by macrophages in mice with lipidemia.

Hypolipidemic Effect of Mannan in Mice with Acute Lipemia Induced by Poloxamer 407.

We studied biological effects of mannan, a polysaccharide immunomodulator from C. albicans, that interacts with mannose receptor in vivo. It is shown that preliminary administration of mannan (5 times in a dose of 50 mg/kg or 2 times in a dose of 100 mg/kg) to mice with acute lipemia induced by lipase inhibitor poloxamer 407 (300 mg/kg) reduces the serum concentrations of atherogenic LDL, cholesterol, and triglycerides. Administration of mannan to intact mice and animals with acute lipemia reduces triglyceride concentration and causes labilization of lysosomal membranes in the liver. Serum activity of chitotriosidase, a marker of macrophage activation, was elevated in mice with acute lipemia treated with mannan. Thus, mannan from C. albicans is a promising hypolipidemic polysaccharide compound, similar by its activity to ß-glycan, a component of LPS.

Depression of Macrophages Modifies Serum Lipid Profile in Hyperlipidemia.

Suppression of functional activity of macrophages by gadolinium chloride, suppressing the macrophage population and the endocytosis velocity, was studied in vivo. Injection of GdCl3 led to an increase in serum cholesterol concentration. Preliminary injection of GdCl3 to mice with lipidemia 24 h before poloxamer 407 reduced the concentrations of triglycerides and LDL during marked depression of macrophages (in 24 h). Macrophage repopulation (days 5, 7) was associated with development of a trend to an increase of triglyceride and LDL levels. lectron microscopic study of Kupffer cells after injection of poloxamer 407 and its combination with gadoliniun chloride detected the intralysosomal accumulation syndrome in these cells (formation of auto- and heterophagolysosomes). Activity of cathepsin B, characteristic of macrophages, reduced 24 h after injections of GdCl3 and poloxamer 407 alone and restored in response to their combination.

Cellular Composition of the Spleen and Changes in Splenic Lysosomes in the Dynamics of Dyslipidemia in Mice Caused by Repeated Administration of Poloxamer 407.

We studied the effect of dyslipidemia induced by poloxamer 407 (300 mg/kg twice a week for 30 days) on cellular composition of the spleen and splenocyte lysosomes in mice. Changes in blood lipid profile included elevated concentrations of total cholesterol, aterogenic LDL, and triglycerides most pronounced in 24 h after the last poloxamer 407 injection; gradual normalization of lipid profile was observed in 4 days (except triglycerides) and 10 days. The most pronounced changes in the spleen (increase in organ weight and number of cells, inhibition in apoptosis, and reduced accumulation of vital dye acridine orange in lysosomes) were detected on day 4; on day 10, the indices returned to normal. Cathepsin D activity in the spleen also increased at these terms. The relationship between changes in the cellular composition of the spleen and dynamics of serum lipid profile in mice in dyslipidemia caused by repeated administrations of relatively low doses of poloxamer 407 is discussed.

The Use of Autologous Mesenchymal Stem Cells for Cell Therapy of Patients with Amyotrophic Lateral Sclerosis in Belarus.

We studied a new method of treatment of amyotrophic lateral sclerosis with autologous mesenchymal stem cells. Autologous mesenchymal stem cells were injected intravenously (intact cells) or via lumbar puncture (cells committed to neuronal differentiation). Evaluation of the results of cell therapy after 12-month follow-up revealed slowing down of the disease progression in 10 patients in comparison with the control group consisting of 15 patients. The cell therapy was safe for the patients.

Role of changes in serum chitotriosidase activity in mice under conditions of hyperlipidemia and lipid-lowering effect of carboxymethylated (1-3)-ß-D-glycan.

Enhanced expression and activity of chitotriosidase in humans is regarded as a marker of atherosclerosis. However, it remains unclear, whether this increase is related to lipemia or enhanced secretion of the enzyme by activated macrophages in the atherosclerotic plaques. It was shown that acute lipemia in mice caused by single administration of poloxamer 407 (P-407) in a dose of 300 mg/kg is accompanied by an increase in serum chitotriosidase activity (24 h) that correlated with elevated content of total cholesterol and triglycerides. Preliminary administration of (1-3)-ß-D-glycan prevented the P-407-induced increase in chitotriosidase activity, probably due to the hypolipidemic action of (1-3)-ß-D-glycan. The relationship between changes in chitotriosidase activity with atherogenic fractions and subfractions of serum lipoproteins during lipemia is discussed.

[Effect of cholesterol on the functional activity of proteins responsible for the resistance of human lymphocytes to xenobiotics].

The influence of agents modifying cholesterol in plasma membranes on the functional activity of transporter proteins (P-glycoprotein (P-gp) and the multidrug resistance protein 1 (MRP1)) in human lymphocytes has been studied. It was shown that changes in lateral distribution of cholesterol using the polyene antibiotic filipin, which disturb the structure and function of glycolipid microdomains in plasma membranes of lymphocytes lead to a decrease in the transport activity of both P-gp and MRP1. It was found that the treatment of human lymphocytes with the cyclic oligosaccharide methyl-beta-cyclodextrine, which leads to cholesterol depletion and reduction of lipid bilayer microviscosity in membranes of these cells, also decreases the functional activity of these proteins. It was concluded that the transport activity of P-gp and MRP1 depends on the modification of cholesterol in the membranes of human lymphocytes, i.e., is closely associated with the level of cholesterol and its lateral distribution.

Neurons and stromal stem cells as targets for polycation-mediated transfection.

Expression of transgenes in neurons and stromal/mesenchymal stem cells (MSC) can greatly enhance their therapeutic potential. In transfection experiments, we studied properties of linear and branched (dendrimers) polycations as transgene delivery vehicles. Linear polyethyleneimine transfected neurons, but was ineffective in MSC. Polyamidoamine dendrimers showed greater transfection efficiency and mean GFP fluorescence intensity compared to phosphorus dendrimers of the same (4th) generation. Expression of neurotrophic factor BDNF in MSC transfected with polyamidoamine dendrimers was also by more than 10 times higher.

Hepatogenic potential of human bone marrow and umbilical cord blood mesenchymal stem cells.

Conditions of human BM and umbilical cord blood MSC in vitro differentiation in the hepatogenic direction were studied. Changes in cell morphology, phenotype, acquisition of the capacity to produce albumin and accumulate glycogen, express cytokeratin, alkaline phosphatase, and albumin mRNA indicated that BM and umbilical cord blood MSC differentiated in vitro into immature hepatocyte-like cells.

Plasticity of human mesenchymal stem cell phenotype and expression profile under neurogenic conditions.

Human bone marrow MSC cultured in neurogenic medium containing EGF and FGFbeta demonstrated alteration of the phenotype and expression of neuronal precursor/early neuron markers nestin and NSE. Signals of expression of neuronal and oligodendroglial markers MAP-2, dm-20, and MBP were detected after prolongation of incubation in neurogenic medium to 2 weeks. Cells with neuronal morphology were immunopositive to early neuronal marker beta-III-tubulin. Replacement of neurogenic medium for alpha-MEM with 10% fetal calf serum induced reversion of the phenotype to that typical for human MSC. This indicates high plasticity of the phenotype and expression profile of neuronal markers in MSC cultured under neurogenic conditions or possibility of dedifferentiation of MSC reaching the stage of neuronal precursors/early neurons.

Viral vectors for stable transduction of human mesenchymal stem cells: systems based on adeno-associated viruses and lentiviruses.

We compared the efficiency of transduction with lentivectors based on HIV-1 and adeno-associated viruses serotype 2 and stability of transgene expression in human mesenchymal bone marrow stem cells.

[Cystatin C: a biological role and impaired secretion in viral hepatitis c and hepatic cirrhosis].

Cystatin C is a non-glycated cationic protein with a molecular weight of 13.3 kD, which belongs to the superfamily of cystatins; its basic function is to inhibit and regulate the activity of cysteine proteinase. In apparently healthy individuals, the extracellular concentration of cystatin C is shown to be substantially higher in serum than in urine and bile. The increased serum concentration of cystatin C has been found in the development of chronic viral hepatitis C, and hepatic cirrhosis in particular, which reflects the development of an inflammatory process and, evidently, the higher secretion of cystatin C by stimulated macrophages.

[Features of transformation of phosphates in Rhodobacter sphaeroides chromatophores]. / Osobennosti prevrashcheniia fosfatov na khromatoforakh Rhodobacter sphaeroides.

We have found the ATP production in the Rhodobacter sphaeroides chromatophores illuminated by single short light flash, that is under conditions when the proton gradient formed as a result of electron transport after the second flash, is absent. The ATP synthesis was accompanied by the H2O2 formation. Simultaneous formation of H2O2 is indicative of the oxidative activation of phosphate during the ATP synthesis, as in the model systems with isolated chlorophyll. These data provide a theoretical background to the fitting of illumination parameters in both laboratory and industrial photobioreactors with photosynthetic bacteria used in biotechnological processes.

[Participation of inorganic phosphates as electron donors in the primary reactions of photosynthesis in Rhodobacter sphaeroides]. / Issledovanie uchastiia neorganicheskogo fosfata kak donora élektronov v pervichnykh reaktsiiakh fotosinteza u Rhodobacter sphaeroides.

The formation of ATP during photophosphorylation in chromatophores from purple nonsulfur bacterium Rhodobacter sphaeroides in the presence of phenazine methosulfate and without exogenous electron carriers under constant illumination and by the action of single light flashes was studied. It was shown that the photoinduced transport of electrons to the exogenous electron acceptor depends on phosphate. It was assumed that phosphate ions are electron donors in the reaction center P870; by the action of light, P870 converts the phosphate ion HPO4(2-) into anion radical HPO4-.. In the difference EPR spectra "light minus darkness" at 77 K, an asymmetrical doublet signal with a weak low-field line was observed. The signal had a g-tensor of about 2.014 and a hyperfine coupling constant of about 2.5 mT and belongs probably to the phosphate anion radical.

[The destruction of microscopic organisms by their irradiation with a special form of UHF electromagnetic signals]. / Razrushenie mikroskopicheskikh organizmov putem ikh oblucheniia SVCh élektromagnitnymi signalami spetsial'noi formy.

Electromagnetic signals of special form produced by an ultra-high frequency generator were used to destroy various microorganisms: baker's yeast; blue-green alga Nostoc muscorum; mold fungus; and two flagellates, plant flagellate Euglena gracilis and an animal flagellate parasitizing on humans. The control samples before irradiation and experimental samples damaged and destroyed by irradiation were examined on a microscope with a computer system of image analysis. The results are presented as computer graph images.

Discrepancy between direct and antibody-dependent cytotoxic activities of human LAK cells.

Human lymphokine-activated killer (LAK) cells display cytotoxic activity against natural killer (NK)-resistant tumor cells in an antibody-independent and -dependent manner. We compared LAK cell-mediated antibody-independent cytotoxicity (LAK activity) and antibody-dependent cellular cytotoxicity (ADCC) against untreated and antibody-coated Raji cells, respectively. Human lymphocytes showed drastically increased LAK activity after stimulation with interleukin-2 (IL-2) for 3 or 7 days when compared to non-activated cells. The level of ADCC was reduced for 3-day-generated LAK cells and augmented for 7-day-generated LAK cells as compared to non-activated cultured lymphocytes. Phenotypical analysis revealed IL-2-induced up-regulation of the proportion of CD11b+ (but not CD16+) lymphocyte subpopulation in 7-day-generated LAK cells. The data imply that human LAK cells exhibit antibody-dependent and -independent cytotoxic activities via distinct effector pathways at different stages of generation. These stages may be associated with changes in adhesion molecule (CD11b/CD18) expression on the surface of IL-2-activated lymphocytes.

[ATP formation in a model system with cytochrome c oxidase]. / Obrazovanie ATP v model'noi sistemy s tsitokhromom c-oksidazoi.

The ability of isolated cytochrome c-oxidase to form ATP is discovered. The process is accompanied by a decrease in inorganic phosphate and oxygen uptake, stimulated by reduced cytochrome c and inhibited by ammonium sulphate, uncoupler SF 6847 and oligomycin. In the ATP-free reaction mixture with cytochrome oxidase and orthophosphate the oxygen uptake is followed by pyrophosphate formation. In the absence of orthophosphate, cytochrome oxidase possesses the adenylate kinase activity which is stimulated by reduced cytochrome c, inhibited by oligomycin and ammonium sulphate and inactivated on heating.

[Pathways of intra-articular transport of cholesterol esters]. / O putiakh vnutrisustavnogo transporta éfirov kholesterina.

The authors have carried out an experimental study of an insufficiently explored problem of the diffusion capacity of the ethers of cholesterol through the skin and the possibility of their intra-articular transport with cholesterol ether of the oleic acid marked 1,2(3)H taken as an example. It has been established that the drug penetrates through the skin and appears in the joint cavity. The results expand our ideas of the biological role of lipids and present the arguments in favour of the hypothesis of their participation in the mechanism of reduction of intra-articular friction.