[Show abstract][Hide abstract] ABSTRACT: Design and synthesis of new derivatives of (–)-cytisine with a wide spectrum of pharmacological
activity, represents a potential therapeutic interest for development of drug candidates for neurodegenerative
disorders, inflammatory diseases, and treatment of nicotine addiction. We used HEK293 cell line, transiently
transfected with NF-κB and STAT1 luciferase reporter constructs, to select (–)-cytisine derivatives for their
potency to modulate basal and induced NF-κB and STAT1 activity. Currently, NF-κB, STAT1 and components of their signaling pathways, are considered as attractive targets for pharmacological intervention, primarily in chronic inflammation, cancer, autoimmune, neurodegenerative and infectious diseases. Library of
tested compounds included derivatives of (–)-cytisine with amino, amide, thionyl and carboxamide groups
at the 3rd, 5th and 12th position in the original molecule, as well as other bimolecular derivatives. Our experimental results revealed compounds with moderate inducing, as well as inhibitory, effects on basal NFκB and STAT1 activity (IC50 or EC50 values are mainly in the micromolar range). The structure–activity relationship analysis demonstrated that mode of activity (activation or inhibition of NF-κB and STAT1) is determined by the topology of substituents in (–)-cytisine molecule, whereas the nature of substitutions determines the severity of the effect (introduction of aromatic and adamantyl substitutions, as well as thionyl or ketone groups are of principal importance). Assessments of effects of (–)-cytisine derivatives on activity of NF-κB and STAT1, induced by specific agents (TNFα and IFNγ, respectively), revealed that certain compounds
inhibited both basal and stimulated activity of NF-κB and STAT1, whereas other compounds showed a dual
effect (increase in basal and decrease in stimulated NF-κB activity), in turn, several compounds increased
both basal and induced activity of NF-κB and STAT1. In summary, obtained results indicate that one possible
mechanism of biological action of (–)-cytisine derivatives lies is their ability to influence components of NF-
κB and STAT1 signaling pathways.
[Show abstract][Hide abstract] ABSTRACT: Background
Noopept (N-phenyl-acetyl-L-prolylglycine ethyl ester) was constructed as a dipeptide analog of the standard cognition enhancer, piracetam. Our previous experiments have demonstrated the cognition restoring effect of noopept in several animal models of Alzheimer disease (AD). Noopept was also shown to prevent ionic disbalance, excitotoxicity, free radicals and pro-inflammatory cytokines accumulation, and neurotrophine deficit typical for different kinds of brain damages, including AD. In this study, we investigated the neuroprotective action of noopept on cellular model of AD, Aß25¿35-induced toxicity in PC12 cells and revealed the underlying mechanisms.ResultsThe neuroprotective effect of noopept (added to the medium at 10 ¿M concentration, 72 hours before ¿ß25¿35) was studied on ¿ß25¿35-induced injury (5 ¿M for 24 h) in PC12 cells. The ability of drug to protect the impairments of cell viability, calcium homeostasis, ROS level, mitochondrial function, tau phosphorylation and neurite outgrowth caused by ¿ß25¿35 were evaluated.Following the exposure of PC12 cells to ¿ß25¿35 an increase of the level of ROS, intracellular calcium, and tau phosphorylation at Ser396 were observed; these changes were accompanied by a decrease in cell viability and an increase of apoptosis. Noopept treatment before the amyloid-beta exposure improved PC12 cells viability, reduced the number of early and late apoptotic cells, the levels of intracellular reactive oxygen species and calcium and enhanced the mitochondrial membrane potential. In addition, pretreatment of PC12 cell with noopept significantly attenuated tau hyperphosphorylation at Ser396 and ameliorated the alterations of neurite outgrowth evoked by ¿ß25¿35.Conclusions
Taken together, these data provide evidence that novel cognitive enhancer noopept protects PC12 cell against deleterious actions of Aß through inhibiting the oxidative damage and calcium overload as well as suppressing the mitochondrial apoptotic pathway. Moreover, neuroprotective properties of noopept likely include its ability to decrease tau phosphorylation and to restore the altered morphology of PC12 cells. Therefore, this nootropic dipeptide is able to positively affect not only common pathogenic pathways but also disease-specific mechanisms underlying Aß-related pathology.
[Show abstract][Hide abstract] ABSTRACT: Test systems for monitoring activities and the search for substances activating or inhibiting transcription factors as biological targets have been designed on the basis of luciferase constructs containing binding sites for transcription factors CREB, NFAT, NF-κB, p53, STAT1, GAS, VDR, HSF1, and HIF1α. An assessment of the functional activity of reporter constructs has been carried out using their transient transfection into HEK293 cells followed by treatment with specific inducers. The functional activity of all reporter constructs was observed based on the increased luciferase expression. In order to evaluate the efficiency of the suggested test systems, aspirin was used. Incubation of cells transfected with the above-mentioned constructs treated with aspirin was accompanied by the suppression of NF-κB, HIF1α, GAS, VDR, and HSF binding activity. The findings revealed for NF-κB, NFAT, and STAT1 confirm the published data concerning the mechanisms of aspirin action. The detected effects of this drug on the HIF1α, GAS, VDR, and CREB activity have been demonstrated for the first time.
[Show abstract][Hide abstract] ABSTRACT: Transgenic tobacco plants expressing the AINTEGUMENTA gene of rape under control of the 35S promoter and the promoter of dahlia mosaic virus were obtained. The transgenic plants were characterized by increase in the length of the leaves, flower sizes, stem height, and weight of seeds; at the same time, the degree of increase was greater in the case of use of the dahlia mosaic virus promoter as a regulator of transcription. Ectopic expression of the AINTEGUMENTA gene promoted prolongation of leaf growth, while sizes of epidermal cells of the leaves remained unchanged.
[Show abstract][Hide abstract] ABSTRACT: Elevation of intracellular Ca²⁺ in T-lymphocytes as a consequence of T cell antigen receptor activation triggers transcriptional programs resulting in effector cytokine secretion and immune response coordination. Increase of Ca²⁺ concentration in T-lymphocytes follows both the Ins(1,4,5)P(3)-dependent release from an intracellular store and subsequent influx from extracellular milieu. Flow cytometry and the fluorescent dye Fluo-4AM have been used to demonstrate that noncompetitive NMDA receptor antagonist (+)-MK801 inhibits Ca²⁺ influx in T cells induced by thapsigargin. Combination of thapsigargin and (+)-MK801 with following incubation does not affect Ca²⁺ mobilization from intracellular stores, while decreased Ca²⁺ entry was observed. Overall data indicate that the ion channel blocker (+)-MK801 is able to inhibit the Ca²⁺ influx and confirm our suggestion about involvement of NMDA receptor in the store-operated Ca²⁺ entry mechanisms in human T-lymphocytes. To identify the signal transduction pathways associated with NMDA receptors in mitogen-stimulated T-lymphocytes, the cells were incubated with (+)-MK801, then activity of key phosphorylated protein kinases of MAP-activated (pERK1/2, pSAPK/JNK, p-p38), Ca²⁺-dependent (pCaMKII), PI3/Akt-dependent (pGSK-3β), and PKC-activated (pPKCθ) pathways were detected. The data we obtained demonstrate that (+)-MK801 treatment leads to more prominent decrease in Ras-activated protein kinases pERK1/2 and Rac-activated proteins p-p38 and pSAPK/JNK, as compared to DAG-dependent pPKCθ and Ca²⁺-dependent pCaMKII. These results show that NMDA receptors are mainly involved in regulation of Ras/Rac-dependent signaling in T-lymphocytes.
[Show abstract][Hide abstract] ABSTRACT: Under action of growth-stimulating concentrations of bioregulator stifun on wheat plants, an increase of functional activity Under action of growth-stimulating concentrations of bioregulator stifun on wheat plants, an increase of functional activity
of nucleoli of meristematic cells; contents of lectin (wheat germ agglutinin); and activity of proteinases, tripsin inhibitors, of nucleoli of meristematic cells; contents of lectin (wheat germ agglutinin); and activity of proteinases, tripsin inhibitors,
and ATPase activity was established. The pool of free amino acids was increased under bioregulator use. Levels of methionine, and ATPase activity was established. The pool of free amino acids was increased under bioregulator use. Levels of methionine,
phenylalanine, cysteine, lysine, leucine and tyrosine were increased. It is likely that stifun could activate protein biosynthesis phenylalanine, cysteine, lysine, leucine and tyrosine were increased. It is likely that stifun could activate protein biosynthesis
in wheat plants. in wheat plants.
[Show abstract][Hide abstract] ABSTRACT: Under action of growth-stimulating concentrations of bioregulator stifun on wheat plants, an increase of functional activity of nucleoli of meristematic cells; contents of lectin (wheat germ agglutinin); and activity of proteinases, tripsin inhibitors, and ATPase activity was established. The pool of free amino acids was increased under bioregulator use. Levels of methionine, phenylalanine, cysteine, lysine, and tyrosine were increased. It is likely that stifun could activate protein biosynthesis in wheat plants.
Prikladnaia biokhimiia i mikrobiologiia 01/2011; 47(6):679-84.
[Show abstract][Hide abstract] ABSTRACT: New approaches to the detection of impaired nucleotides based on the allele specific ligation of a "C probe" followed by rolling circle amplification have been developed. The detection of amplification products was realized by using enzymatic and deoxyribozyme digestion of fluorescently-labeled DNA-RNA-DNA chimeric oligonucleotide structures in cycling probe technology (CPT) in real-time mode.
[Show abstract][Hide abstract] ABSTRACT: Plant responses to cadmium, whose accumulation may cause various disturbances in metabolic processes, can be represented as a multicomponent integrative response model (in particular, as a gan-shaped response) . In view of this, it is reasonable to use a complex approach to analyzing plant responses to cadmium, which may include studies of plant adaptation, cadmium accumulation, and detoxication. The goal of this work was to study plant responses to cadmium and its accumulation in plants. The study included characterizing the resistance of plants by changes in the proportion of linear sizes and weight; determination of the degree of hydration, phytohormone balance, and the content of free amino acids; establishing the mechanisms of occurrence of chromosome rearrangements on the basis of analysis of the distribution of chromosome aberrations in cells and the aberration index under exposure to cadmium; and assessment of the retaining ability and barrier function of roots during cadmium entry into sprouts. The study was performed with the cibol ( Allium fistulosum L.) cultivars Gribovskii and Russkii zimnii; the spring wheat ( Triticum aestivum L.) cultivars Zhnitsa, Irmenka, and Omskaya-35; the maize ( Zea mays L.) cultivar Zhemchug; and the rice ( Oryza sativa L.) cultivar Rapan. Seeds were sterilized with 70% ethanol. Seedlings were grown in Petri dishes on filter paper wetter with water in a constant-temperature cabinet at 24‐27 ° C. Aligned 48-h-old seedlings were incubated with cadmium acetate for 18, 36, and 54 h (cibol); 24, 48, 72, 96, and 120 h (maize and wheat); and 1, 24, and 48 h (rice). In addition, wheat seeds were allowed to germinate at 24 ° C for 24 h, placed on cork rafts with 4-mm holes, and grown in vessels filled with cadmium acetate for 14 days. During the entire experiment, solutions were aerated and their volume was maintained constant by adding distilled water. Distilled water was used as a control. The resistance index was determined by the ratio between the plant weight in the presence of cadmium and in the control . We studied the effect of cadmium on the intensity of division of apical meristematic cells, the nucleolus characteristics, the level of chromosome aberrations in root meristematic cells (by metaphase and anaphase methods), the content of phytohormones (abscisic acid (ABA), indolylacetic acid (IAA), and cytokinins by enzyme immunoassay), as well as the content of free amino acids by ionexchange chromatography. The content of cadmium was determined by the Experiments were performed in quadruplicate and repeated at least five times. The statistical significance of differences between variants was estimated by Student’s t test. In the presence of cadmium at concentrations of 100, 10, and 1 mg/l, the resistance index of wheat was 0.75, 0.98, and 0.92 (Zhnitsa); 0.69, 1.03, and 1.05 (Omskaya-35); and 0.73, 0.88, and 1.05 (Irmenka), respectively. At these concentrations, the sprout/root ratio obtained after determination of linear sizes was 0.70, 1.31, 0.72, and 0.70 (Zhnitsa); 0.51, 1.06, 0.51, and 0.61 (Omskaya-35); and 0.63, 1.41, 0.70, and 0.60 (Irmenka), respectively. In the presence of 100 mg/l cadmium, the degree of hydration of plants significantly decreased: by 45% (Zhnitsa), 41% (Irmenka), and 41% (Omskaya-35). At concentrations of 10 and 1 mg/l, cadmium had no effect on the degree of hydration. The potential of wheat resistance to cadmium determined at early developmental stages in the Barsukova medium varied from very low (0.21) to very high (1.2) . Thus, we did not reveal significant genotypic differences in plant responses to cadmium at the concentrations used.
[Show abstract][Hide abstract] ABSTRACT: The physiological activity of the plant growth regulator Epin-extra is investigated under conditions of sodium chloride salinity,
cadmium stress, and low temperature. Epin-extra lessens the negative effect of stress factors on growth of spring wheat, Welsh
onion, and cabbage: it reduces the level of cadmium-induced chromosome aberrations and concentration of this metal in plants
exposed to a cadmium acetate solution. An increase of the level of expression of the cabbage cold shock protein gene (CSP5) under the effect of the bioregulator is established by the real-time PCR method with the use of interprimer fluorescence
resonance energy transfer.
[Show abstract][Hide abstract] ABSTRACT: The effect of stifun on wheat, Welsh onion, and corn plants under the effect of cadmium is investigated. The protective effect
of this bioregulator manifested itself in preventing inhibition of growth, stabilizing mitotic phases, and reducing the level
of chromosomal aberrations. The results of histochemical investigations permit the assumption that growth regulators can reduce
the uptake of cadmium ions into plant tissues.
[Show abstract][Hide abstract] ABSTRACT: Competitiveness and genetic variation of the Rhizobium galegae strains from the collection of the All-Russia Institute of Agricultural Microbiology, Russian Academy of Agricultural Sciences,
causing nodulation of oriental goat’s rue under conditions of Bashkortostan soils (lacking this rhizobial species) were studied.
It was demonstrated that of all the tested strains, the strains CIAM 0702 and CIAM 0704, each carrying two megaplasmids of
1500 and 2000 MDa, were the most competitive. RAPD (random amplified polymorphic DNA) analysis showed that R. galegae strains were able to intensively exchange the genetic material in the host plant rhizosphere. We did not succeed in detecting
the local root nodule bacteria that were either initially able to infect oriental goat’s rue or had adapted to infecting this
species due to various genetic rearrangements.
[Show abstract][Hide abstract] ABSTRACT: The effect of benzyladenine (BA) on the activation of rRNA gene transcription was studied in wheat (Triticum aestivum and T. urartu) as related to the phenomenon of nucleolar dominance and the changes in the extent of methylation of the intergenic spacers
in the subgenome A. The method of polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to
analyze the fragments of rDNA promoter regions amplified with the primers designed to recognize the sites of DNA isolated
from BA-treated seedlings of diploid T. urartu and hexaploid T. aestivum and desaminated with metabisulfite. The subsequent genomic bisulfite sequencing of the amplification products was used to
evaluate the level of methylation/demethylation of the particular cytosine residues. BA diminished methylation of cytosine
residues in rDNA promoter regions to the level, which was different in two wheat species; these data presume that the transcriptional
activities of rRNA genes in various wheat subgenomes depend on the extent of their methylation.
[Show abstract][Hide abstract] ABSTRACT: The Atlas Rat cDNA Expression Array (BD Biosciences, United States) has been used to analyze changes in the expression of 588 genes in rat brain cells in response to a single administration of Ladasten, a 2-aminoadamantane derivative that has psychostimulating and anxiolytic effects. The analysis of hybridization on macroarrays, confirmed by the results of real-time quantitative RT-PCR, has demonstrated that Ladasten alters the expression of 12 genes in the rat brain. The GAT3 and CARBH genes are presumed to be pharmacologically important targets of Ladasten. The changes in their activity explain the mechanisms of the anxiolytic and mood-stabilizing effects of the drug. Ladasten has been shown to induce the genes whose products are involved in various signal pathways (APC, Rb, PKCIP, and PMCA), as well as the genes of cytoskeletal proteins (Tub1 and actin), synaptic proteins (SynIA&IB and PLP), and enzymes (Gapdh and NSE). The proteins encoded by these genes are presumably involved in compensatory and/or neuroplastic adaptation to the effects of Ladasten.
[Show abstract][Hide abstract] ABSTRACT: We have used the Rat Atlas cDNA Array ("BD Bioscience") to assess changes in mRNA expression of 588 genes in rat brain after acute treatment of 2-aminoadamantane compound--Ladasten. Drug exhibits the psychostimulating and anxyolitic actions. The analysis of results of hybridization on macrochips and their corroboration by quantitative real-time RT-PCR has allowed to reveal 12 genes, expression of which changes in response to ladasten in rat brain cells. The GAT3 and CARBH genes should be considered as primary pharmacologically significant targets and the changes of their functional conditions allows to explain the distinct mechanisms of anxyolitic properties of the drug. It was shown that Ladasten induced genes are involved in the different signalling pathways (APC, Rb, PKCIP, PMCA), genes encoding the cytosceletal proteins (Tubal, actin), synaptic proteins (Syn IA&IB, PLP) and metabolism enzymes (Gapdh, NSE). It is possible to assume, that proteins, encoded by the given genes participate in the compensatory and/or neuroplastic adaptation to biochemical effects of Ladasten.