Effects of novel hexahydropyrimidine derivatives as potential ligands of M1 muscarinic acetylcholine receptor on cognitive function, hypoxia-induced lethality, and oxidative stress in rodents.

The neurodegenerative diseases have a complex pathogenetic mechanism comprising oxidative stress and receptor system dysfunction caused by various damaging factors such as, for example, brain hypoxia. The purpose of this study was to elucidate the influence of hexahydropyrimidine derivatives on learning, memory, and orientation and locomotor activities in the passive avoidance (PA) and open field (OF) tests and to evaluate these compounds for their potential antihypoxic and antioxidant action on normobaric hypercapnic hypoxia and toxic hypoxia models. We demonstrated that compounds 1a and 1e administered as a single 100 mg/kg dose (p.o.) one hour before the tests increased the latency time to enter the dark compartment for the first time and reduced the time spent in the dark compartment on the 2nd, 7th, and 14th days of PAT and increased the number of squares crossed and hole-pokings in the OF test. It was also shown that single administration of compounds 1a and 1e (in 100 mg/kg dose, p.o.) one hour before generation of hypoxia increased the life span of mice under normobaric hypoxia by 30% (P < 0.05) and, after injection of sodium nitroprusside, they decreased the malondialdehyde (MDA) level and increased the catalase level in the brain of mice. According to molecular docking results, compounds 1а and 1е are bound in the orthosteric active site of M1 muscarinic receptor via supramolecular interactions with a number of functional amino acids. The results indicate that hexahydropyrimidine derivatives have a beneficial effect on the memory, learning processes, and orientation and locomotor activities of rats in an unfamiliar environment and exhibit antihypoxic and antioxidant activities under hypoxia in mice. The cognitive enhancement can be mediated by the effect of lead compounds on the M1 muscarinic acetylcholine receptor.

Nootropic Activity of a Novel (-)-Cytisine Derivative (3aR,4S,8S,12R, 12aS,12bR)-10-Methyl-2-Phenyloctahydro-1H-4,12a-Etheno-8,12-Methanopyrrolo[3',4':3,4]Pyrido[1,2-a] [1,5]Diazocine-1,3,5(4H)-Trione.

We performed screening of nootropic properties of 10 new derivatives of quinolizidine alkaloid (-)-cytisine. Compounds with ß-endo stereochemistry were more active than α-endo-isomers. Under stress conditions (3aR,4S,8S,12R,12aS,12bR)-10-methyl-2-phenyloctahydro-1H-4,12a-etheno-8,12-methanopyrrolo[3',4':3,4]pyrido[1,2-a] [1,5]diazocine-1,3,5(4H)-trione enhanced memory and had a positive effect on cognitive functions of rats. According to molecular docking data, the nootropic activity of the compound can be associated with its affinity for the glutamate-binding subunits GluK1 and GluR2 of the kainate and AMPA receptor, respectively.

Quantitative analysis of structure-activity relationships of tetrahydro-2H-isoindole cyclooxygenase-2 inhibitors.

Using the GUSAR program, structure-activity relationships on inhibition of cyclooxygenase-2 (COX-2) catalytic activity were quantitatively analyzed for twenty-six derivatives of 4,5,6,7-tetrahydro-2H-isoindole, 2,3-dihydro-1H-pyrrolyzine, and benzothiophene in the concentration range of 0.6-700 nmol/liter IC50 values. Six statistically significant consensus QSAR models for prediction of IC50 values were designed based on MNA- and QNA-descriptors and their combinations. These models demonstrated high accuracy in the prediction of IC50 values for structures of both training and test sets. Structural fragments of the COX-2 inhibitors capable of strengthening or weakening the desired property were determined using the same program. This information can be taken into consideration on molecular design of new COX-2 inhibitors. It was shown that in most cases, the influence of structural fragments on the inhibitory activity of the studied compounds revealed with the GUSAR program coincided with the results of expert evaluation of their effects based on known experimental data, and this can be used for optimization of structures to change the value of their biological activity.

[Animal in vivo model of arrhythmia for genes target identification for 5-amino-exo-3-azatricyclo[5.2.1.0(2,6)]decan-4-one].

The goal of the current work is to study the molecular mechanisms underlay the action of 5- amino-exo-3-azatricyclo[5.2.1.0(2,6)]decan-4-one (P-11) with combined antiarrhythmic, nootropic, anti-inflammatory and anaesthetic activities. The aconitine-induced experimental rat model of cardiac arrhythmia has been used in our study. Aconitine was administered once intravenously in a dose 50 microg/kg whereas experimental animal group received P-11 in a dose 0.3 mg/kg (the compound was injected intravenously 2 min before acute aconitine treatment). Expression macroarray (Atlas Rat cDNA Expression Array, #7738-1; BD Biosciences) was used to identify the target genes for P-11 compound. Comparative analysis of changes in the status of expression of genes in the heart of rats induced by P-11 against the simulated in vivo arrhythmia identified 16 genes that reproducibly alter the level of expression.These genes encode the extracellular matrix proteins (glypican 1, Gpc1; tissue inhibitor of metalloproteinase 2, 3, Timp2, Timp 3); intracellular signaling molecules (rho GTPase activating protein 7, Dlc1; protein tyrosine phosphatase 4a1, Ptp4a1; phosphodiesterase 4D, PDE4D; PI3-kinase regulatory subunit alpha, PIK3R1; guanine nucleotide binding protein alpha 12, Gna12) and protein of intermediate junctions (junction plakoglobin, Jup), proteins involved in glycolysis (phosphofructokinase I, Pfk1) and hemostasis (tissue plasminogen activator, Plat), plasma membrane transporters (Solute carrier family 16, member 1, Slc16a1; ATPase, Na+/K+ transporting, Atp1a), and ets. (c-fos protooncogene, c-fos; telomerase protein component 1, tlp; Annexin 1, anxa 1). Thus, the data about the selective effect of P-11 on genes whose products are involved in the aritmogenesys mechanisms, allow us to consider this compound as a promising means of pathogenetically oriented pharmacotherapy of cardiac arrhythmias.

Choleretic activity of 2-demethoxycarbonyl-2-ethoxycarbonyl-11-deoxymisoprostol on the model of CCl4-induced hepatitis.

Therapeutic administration of 11-deoxymisoprostol had a hepatoprotective effect, which manifested in a decrease in the content of alanine transaminase and aspartate transaminase in blood plasma, and produced a choleretic effect in rats with CCI4-induced toxic hepatitis.

[Effect of 11-deoxymisoprostol ethyl ether sodium salt on thrombocyte aggregation and prothrombin time].

11-Deoxymisoprostol demonstrates antiaggregant properties with respect to the adrenalin-, collagen-, and ADP-induced aggregation of thrombocytes, which is manifested by a decrease in the rate of blood platelet agglutination and their secretion, and by an increase in the time of thrombus formation.

[Hepatoprotective effect of 2-demethoxycarbonyl-2-ethoxycarbonyl-11-deoxymisoprostol].

2-Demethoxycarbonyl-2-ethoxycarbonyl-11-deoxymisoprostol (11-DMP) produces antioxidant effect on the models of toxic hepatitis induced by paracetamol and carbon tetrachloride. The drug normalizes the lipid peroxidation (LPO) prosess in rat liver of the rat and the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the rat blood, thus demonstrating hepatoprotective action.

[Nonsteroidal anti-inflammatory drugs. Declaration I. A study of interrelation "structure--the effectiveness of anti-inflammatory action"].

Using the computer system SARD-21 (Structure Activity Relationship & Design) the structural features typical for high- and low- effective nonsteroid anti-inflammatory drugs (NSAIDs) were analyzed. This information has been used for the model for prediction of anti-inflammatory effectiveness of medicines with 76% and 81% level of recognition by two methods. New data can be used for creating new highly effective NSAIDs, and for increasing effectiveness of already known components.

Effect of glialin on cardiac ventricular arrhythmias and myocardial conduction system in dogs.

Intravenous glialin in a dose of 7 mg/kg suppressed the number of ectopic contractions caused by double ligature of the left coronary artery by the method of Harris and almost 2-fold prolonged animal life-span in comparison with the control. The maximum antiarrhythmic effect of glialin developed after 180 min and persisted for 5 h. Glialin injected intravenously (10 mg/kg) after myocardial infarction under conditions of programmed electrical stimulation inhibited conduction of evoked impulse in the atria, Purkinje fibers, and ventricular myocardium and did not modify the effective refractory periods of the atria and ventricles.

[Some aspects of the antiarrhythmic effect of glialin].

The antiarrhythmic activity of allapinine and glialin (a complex of allapinin and glycyrrhizic acid) was studied on models of arrhythmias induced in rats and guinea pigs by intravenous administration of calcium chloride, aconitine, barium chloride, and strophanthin. The antiarrhythmic activity of glialin is qualitatively analogous to that of allapinine. The advantage of glialin over allapinin is its low toxicity, which is due to the presence of glycyrrhizic acid.

Gastroprotective properties of 11-deoxymisoprostol (prostaglandin E1 analog) and its effect on the level of sialic acids in gastric tissue of rats with peptic ulcer.

11-Deoxymisoprostol (prostaglandin E1 analog) exhibited a pronounced gastroprotective effect on various models of experimental ulcers induced by nonsteroid antiinflammatory drugs. A relationship between high resistance of the gastroduodenal mucosa under the effect of 11-deoxymisoprostol and changes in the level of sialic acid was detected.

[Study of pharmacological properties of betulin bishemiphthalate]. / Issledovanie nekotorykh farmakologicheskikh svoistv bisgemiftalata betulina.

The results of pharmacological tests showed that betulin bishemiphthalate possesses hepatoprotector, antioxidant, and immunotropic properties. Administered in combination with hydroxymethyluracil, that betulin bishemiphthalate prevented the loss of experimental animals upon irradiation.

[Pharmacological properties of 11-deoxymisoprostol]. / Farmakologicheskie svoistva 11-dezoksimizoprostola.

11-Deoxymisoprostol showed gastroprotector activity on the acute models of ulcers induced by acetylsalicylic acid and ethanol and produced curative effect on the chronic ulceration model induced by acetic acid. The positive effect is manifested by a decrease in the number of destructions and in the total area of chronic damage in the mucous membrane of the stomach. In addition, 11-deoxymisoprostol showed antiphlogistic activity on the acute edema models induced by carrageenan and formalin, by decreasing the model foot edema growth in experimental animals. The drug also decreased the level of lipid peroxidation in the rat blood serum on the background of acute ethanol ulceration.

[Synthesis and pharmacological activity of betulin dinicotinate]. / Sintez i farmakologicheskaia aktivnost' dinikotinata betulina.

The assignment of NMR resonances of lupane triterpenoids was refined by the example of 3,28-dinicotinoylbetulin, obtained by acylation of betulin. Hepatoprotective, untiulcer, antiinflammatory, reparative, and anti-HIV activities were found for the compound. In addition, it was demonstrated to have immunomodulatory activity, for the first time detected among lupane triterpenoids. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2002, vol. 28, no. 6; see also http://www.maik.ru.

[Effect of pyrimidine derivatives on the skin reparative regeneration during stress in laboratory animals]. / Vliianie nekotorykh proizvodnykh pirimidina na reparativnuiu regeneratsiiu kozhi laboratornykh zhivotnykh pri stresse.

Experiments on rats showed that some pyrimidine derivatives stimulate the skin repair in animals with thermal and chemical burns under stress conditions. The efficacy of compounds tested increases in the following order: 2-methyl-4-amino-6-hydroxypyrimidine < hydroxymethyluracil < methyluracil.

[Synthesis of the lupane group triterpenoids and there hepatoprotective activity]. / Sintez éfirov triterpenoidov gruppy luoana i ikh gepatoprotektnaia aktivnost'.

Hemisuccinates, hemiphthalates, acetylsalicylates, cinnamates, and p-methoxycinnamates of lupeol, betulin, and 3-O-acetylbetulin were synthesized via interaction with corresponding acid anhydrides or acid chlorides. A number of betulin esters in position 3 and 28 were shown to exhibit a pronounced hepatoprotective effect similar to that of betulin and silibor. These experimental data were in a good agreement with the computer prediction of their biological activity. Betulin 3,28-bis-hemiphthalate was more effective than carsil in models of experimental hepatitis caused by carbon tetrachloride, tetracycline, and ethanol.

[The anti-ulcer action of dibunol (Tonarol)]. / Protivoiazvennoe deistvie dibunola (tonarola).

In experimental study of antiulcerative activity of dibunol on various models of gastric ulcers in rats the drug caused a marked antiulcerative effect in all of them, reduced the incidence of ulcer formation, and shortened the time of ulcer healing. In a model of "acetic" ulcer dibunol oil solution led to quick normalization of lipid peroxidation in the gastric mucosa, which was evidence of high antioxidant activity in cases of ulcer lesions.

[The effect of pyrimidine derivatives on experimental stomach ulcers in rats]. / Vliianie nekotorykh proizvodnykh pirimidina na éksperimental'nye iazvy zheludka u krys.

Experiments on albino rats showed that pyrimidine derivatives reduce hemorrhagic damage of the gastric mucosa caused by indomethacin, acetylsalicylic acid, and ortophen. The derivatives of pyrimidine prevent the decrease in total acid phosphatase activity, increase alkaline phosphatase, and reduce the activity of lactate dehydrogenase.

[Pyrimidine derivatives increase antibiotic therapy efficacy after ionizing irradiation]. / Proizvodnye pirimidina povyshaiut éffektivnost' antibiotikoterapii pri ioniziruiushchem obluchenii.

Pyrimidine derivatives increased the antibiotic therapy efficacy in albino rats irradiated with RUM-7 apparatus for close-focus roentgenotherapy. 2-Methyl-4-amino-6-oxypyrimidine was twice as efficient as oxymethyluracil and 6 times as efficient as methyluracil in the stimulation of the skin reparative regeneration. When the total irradiation was performed with LUCH-1 apparatus in a dose of 6 Gy the pyrimidine derivatives also increased the antibiotic therapy efficacy. After the prophylactic use of the pyrimidine derivatives for 7 days prior to the total irradiation their therapeutic effect increased, the level of the exudative component lowered, the tissue epithelization increased, the terms of the wound healing decreased and the animal lifespan increased.

[Improvement of effectiveness of antibiotic therapy by pyrimidine derivatives in reparative regeneration of skin in rats]. / Povyshenie éffektivnosti antibiotikoterapii proizvodnymi pirimidina pri reparativnoi regeneratsii kozhi u krys.

It was shown on noninbred albino rats with various affections of the skin that pyrimidine derivatives stimulated the skin reparative regeneration and increased the efficacy of antibiotic therapy of Staphylococcus and Proteus infected wounds. The therapeutic effect of 2-methyl-4-amino-6-oxypyrimidine was much higher than that of oxymethyluracil or methyluracil. The pyrimidine derivatives proved to be universal accelerators for reparative regeneration, were compatible with antibiotics and increased their efficacy.