[Cellular test systems for the search for transcription factor activity modulators].

Test systems for monitoring activities and the search for substances activating or inhibiting transcription factors as biotargets have been designed on the basis of luciferase constructs containing binding sites for transcription factors CREB, NFAT, NF-kB, p53, STAT1, GAS, VDR, HSF1, and HIF1alpha. 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-kB, HIF1alpha, GAS, VDR, and HSF binding activity. The findings revealed for NF-kB, NFAT, and STAT1 confirm the published data concerning the mechanisms of aspirin action. The detected effects of this drug on the HIF1alpha, GAS, VDR, and CREB activity have been demonstrated for the first time.

Mechanisms of action of ladasten: activation of gene expression for neurotrophins and mitogen-activated kinases.

We studied the effects of single treatment with ladasten (50 mg/kg) on the content of effector kinases of the mitogen-activated cascade (ERK1/ERK2), pERK1/ERK2 activity (Thr202/Tyr204), and expression of genes for neurotrophic factors BDND and NGF in the striatum, hypothalamus, and hippocampus of rats.

Time course of histone deacetylase 1 and acetylated H3 and H4 histones in the brain of rats treated with ladasten.

We studied the effects of single intragastric administration of ladasten in a dose of 50 mg/kg on the time course of histone deacetylase 1 (HDAC1) and levels of acetylated histones H3 (Lys9) and H4 (Lys8) in the striatum, hippocampus, and hypothalamus. Ladasten reduced HDAC1 level in rat striatum and hippocampus and modified H3acK9 and H4acK8 levels in various structures of rat brain.

Proteomic analysis and identification of ladasten target proteins in rat brain.

Two-dimensional electrophoresis and mass spectrometry detection were used to evaluate the range of proteins in rat brain after single treatment with ladasten (50 mg/kg). We identified 13 proteins with various levels of expression.

[Effect of the novel nootropic and neuroprotective dipeptide noopept on the streptozotocin-induced model of sporadic Alzheimer disease in rats].

Streptozotocin-intracerebroventricularly treated rats are proposed as an experimental model of sporadic Alzheimer disease (AD). Diabetogenic toxin streptozotocin (STZ) administered in both cerebral ventricles in a dose of 3 mg/kg decreases the expression of NGF and BDNF mainly in the hippocampus and increases the content of malonic dialdehyde (MDA)--a product of lipid peroxidation--in the brain tissues. These metabolic changes are accompanied by a pronounced cognitive deficiency, which is manifested by long-term memory deterioration in the passive avoidance test. These manifestations of pathology are not accompanied by hyperglycemia in the case of intraventricular STZ administration, in contrast to the systemic (in particular, intraperitoneal) route of introduction that causes a pronounced increase in the blood glucose level. These results are consistent with the existing notions that (i) STZ administered intraventricularly provokes a complex of changes imitating the sporadic AD and (ii) this disease can be considered as a manifestation of type-III diabetes. The new original cognition enhancing and neuroprotective dipeptide noopept decreases the aforementioned metabolic changes and the accompanying long-term deterioration of the memory. Previously, this systemically active dipeptide was shown to be capable of increasing expression of NGF and BDNF in the hippocampus, stimulating the antibody production to beta-amyloid, inhibiting the lipid peroxidation, activating the endogenous antioxidant systems, and decreasing the rate of glutamate release (cholinopositive effect). Taken together, these data indicate that noopept can be considered as a multipotent substance acting upon several important pathogenic chainsof the sporadic AD.

[On the mechanism of noopept action: decrease in activity of stress-induced kinases and increase in expression of neutrophines].

The influence of noopept (N-phenylacetyl-L-prolylglycine ethyl ester, GVS-111)--a drug combining the nootrope and neuroprotector properties--on the activity of mitogen-activated protein kinases (MAPKs) and the level of NGF and BDNF gene and protein expression in the frontal cortex, hippocampus, and hypothalamus has been studied in rats. Under conditions of chronic administration (28 days, 0.5 mg/day, i.p.), noopept decreased the activity of stress-induced kinases (SAPK/JNK 46/54 and pERK1/2) in rat hippocampus and increases the level of mRNA of the BDNF gene in both hypothalamus and hippocampus. The content of BDNF protein in the hypothalamus was also somewhat increased. In the context of notions about the activation of stress-induced kinases, as an important factor of amyloidogenesis and tau-protein deposition in brain tissue, and the role of deficiency of the neurotrophic factors in the development of neurodegenerative processes, the observed decrease in the activity of stress-activated MAPKs and increased expression of BDNF as a result of noopept administration suggest thatthis drug hasaspecific activity withrespect to some pathogenetic mechanisms involved in the Alzheimer disease.

Changes in CREB (SER133) content and DNA-binding activity of transcriptional factors in rat brain cells against the background of ladasten exposure.

We studied the effects of single administration of ladasten (50 mg/kg) on the level of transcriptional factor CREB (cyclic AMP response binding element protein) phosphorylated by Ser133 in rat striatum, hypothalamus, and hippocampus. Transcriptional factors with affected DNA-binding activity were identified in brain cells.

The effects of ladasten on dopaminergic neurotransmission and hippocampal synaptic plasticity in rats.

Derivatives of adamantane, like memantine, are potentially neuroprotective drugs for the favourable care of Alzheimer's and Parkinson's diseases. A further adamantane derivate is N-(2-adamantyl)-N-(para-bromophenyl)-amine (ladasten) which is capable to modulate animal performance in different learning paradigms. To clarify if some of those behavioural alterations are mediated by modulation of catecholamine syntheses we studied the effects of single administration of ladasten (50 mg/kg, per os) on catecholamines' biosynthesis in the ventral tegmental area, nucleus accumbens, hypothalamus, striatum and hippocampus. We found that ladasten differentially regulates tyrosine hydroxylase mRNA and protein as well as dopamine and L-DOPA content. We then investigated the effects of ladasten on activity-dependent hippocampal synaptic plasticity in vitro and found that application of 10 microM ladasten transforms short-term potentiation of synaptic transmission to a long-lasting form. A transformation of short-term into long-term potentiation was also observed, when ladasten was applied 40 min after a single 100 Hz 200 ms tetanization. This reinforcement was blocked by the protein synthesis inhibitor anisomycin and could be attenuated by the D1/D5 receptor antagonist SCH23390. These results suggest that ladasten induces reinforcement of short-term potentiation via protein synthesis and dopamine dependent mechanisms.

[The effect of ladasten on the activation-induced expression of Fas receptor on T-lymphocytes and their sensitivity to Fas-induced apoptosis]. / Vliianie Ladastena na aktivatsionno-indutsirovannuiu ékspressiiu Fas-retseptora na T-limfotsitakh i ikh chustvitel'nost' k Fas-indutsirovannomu apoptozu.

The effects of ladasten on the activation-induced expression of Fas-receptor on T-lymphocytes, their sensitivity to Fas-induced apoptosis, and the expression of mitogen-activated ERKI/ERK2 protein kinases have been studied. In the range of concentrations 0.1-10 microM, ladasten exhibited a comitogenic effect on the TCR-mediated stimulation of T-lymhocytes ion the peripheral human blood, which was accompanied by an increase in the level of phosphorylated form of ERK-2. At the same time, ladasten virtually did not change the activation-induced expression of Fas-receptor on T-lymphocytes, but reduced the rate of the Fas-induced apoptosis. It was concluded that the immunoprotective effect of ladasten is probably based on a decrease in the rate of Fas-induced apoptosis.

[The effect of ladasten on the activity of cAMP-dependent protein kinases and the phosphorylation of proteins in brain cells of rats]. / Vliianie ladastena na aktivnost' cAMP-zavisimykh proteinkinaz i fosforilirovanie belkov v kletkakh golovnogo mozga krys.

The effect of ladasten (50 mg/kg) on the activity of cAMP-dependent protein kinases (represented by protein kinase A (PKA)) in the soluble protein fraction of rat brain was studied. Changes in the PKA activity were monitored in the initial period of drug action (1-12 h). In this stage, ladasten increased the PKA activity, and the level of phosphorylation of one isoform of the main protein myelin (14 kD) and of the proteolipid protein (30 kD). It is concluded that the pharmacological activity of ladasten is related to both cAMP-dependent and cAMP-independent signaling systems.

[Effect of ladasten on the proteinase C activity in the rat brain cells]. / Vliianie ladastena na aktivnost' proteinazy C v kletkakh golovnogo mozga krys.

The effect of ladasten (50 mg/kg) on the activity of protein kinase C (PKC) in rat brain was studied depending on the duration of drug action. In the initial stage of the drug action, the PKC activity in the cytosol fraction of rat brain proteins exhibits a more than twofold increase. The effect is independent of the presence of exogenous Ca2+ and is inhibited by cinnarizine and nifedipine. The optimum Ca2+ concentration is maintained due to the activation of Ca2+ ATPase. It is concluded that the pharmacological activity of ladasten is related to activation of Ca2+ phospholipid-dependent protein kinases.