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Resume. Aim. Glaucoma is a whole group of diseases caused by increased intraocular pressure (IOP), leading to atrophy of the optic nerve and irreversible blindness. Melatonin has a wide range of biological activity, including antioxidant and antiglaucoma, but its use is limited by insufficient stability and duration of action. To search for new, more effective antiglaucoma agents among derivatives of 3-arylidene-2-oxindole, melatonin analogues, a search for quinonoxidoreductase 2 (NQO2) inhibitors was performed, antioxidant activity was determined and the effect of active compounds on intraocular pressure was studied. Materials and methods. The study of inhibitory activity against NQO2 was evaluated kinetically using menadione and N-benzyl-dihydronicotinamide as substrate and co-substrate, respectively. Antiradical activity was studied for reducing superoxide-dependent luminescence in a reaction medium containing hemoglobin, luminol and hydrogen peroxide using the Infinite M200 PRO microplate reader (Tecan, Austria), as well as for free radical binding tests OH, ABTS and DPPH. Cytotoxicity assessment was carried out using a standard MTT test on MCF-7 and HepG2 line cells. Intraocular pressure in laboratory animals was measured using a contact veterinary tonometer Tonovet (Finland). Results. Derivatives of 3-arylidene-2-oxindole have demonstrated significant antioxidant activity. A number of NQO2 inhibitors have also been identified. The most active compound inhibits human NQO2 with an IC50 of 0,4 pM. The compound also showed antiradical activity, binding the superoxide anion to IC50 of 6,1 pM, superior to melatonin on both counts, and low cytotoxicity. With topical application of a 0,4% solution, the compound reduced the intraocular pressure of intact rats by (40,9 ± 6,4) %, while not having a systemic hypotensive effect. Conclusion. Derivatives of 3-arylidene-2-oxindole are promising for drug discovery for the treatment of eye diseases associated with increased intraocular pressure or oxidative stress, such as glaucoma, uveitis and diabetic retinopathy.

Abstract Six compounds of the 5(7)-alkylamino-6-nitroazolopyrimidine and 8-alkylazolo[5,1-b]purine series were selected based on the structural analysis of A1 adenosine receptor inhibitors and the role of this biological target in the modulation of intraocular pressure, an important factor in the pathogenesis of glaucoma. These heterocycles were shown to exhibit a weak affinity towards the A1 adenosine receptor on an in vitro model of the adenosine-dependent change of the chronotropic effect on isolated atria of white mice. On the other hand, thiadiazolo[3,2-a]pyrimidines and triazolo[5,1-b]purine displayed an in vivo hypotensive effect in rats. The leading compound, 5-methyl-8-(hydroxyethyl)triazolo[5,1-b]purine) (0.2% solution), caused a 34% reduction of ophthalmotonus in 3 h without an adverse resorptive effect. In addition, using the MTT-test it was shown on the human HepG2 cell line that the heterocycles affecting the intraocular pressure were by one to two orders of magnitude less cytotoxic than the reference doxorubicin.

The aim of this study was to evaluate the immediate results of the stereotactic radiosurgery (SRS) application in patients with choroid melanoma.Material and methods. The prospective study included 43 patients who were diagnosed with choroidal melanoma cT1–3N0M0.SRS was performed on a Gamma Knife gamma therapeutic unit, Perfexion (Elekta, Sweden). Under local anesthesia, the eyeball was immobilized using frenulum sutures on the rectus muscles. The median prescribed dose per tumor margin at 50% isodose was 30 Gy. The immediate effect of the treatment was assessed as positive (local control) in all cases, except increased blood flow according to Doppler ultrasound, an increase in tumor size by more than 20% of the previously determined lesion according to MRI.Results. During the follow-up period (median follow-up — 16 months), there were no cases of negative outcome in terms of local tumor control.A statistically significant gradual decrease in tumor thickness was revealed during the entire observation period (6.6±2.1 mm before treatment, 5.3±2.1 mm 12 months after treatment, p˂0.001), stabilization of the tumor base (12.25±3.26 mm before treatment, 11.4±2.5 mm 12 months after treatment, p=0.355). Contrast-enhanced MRI also showed a progressive statistically significant decrease in tumor volume (635.21±328.32 mm3 before treatment, 376.0±267.6 mm3 15 months after treatment, p˂0.001). The eyeball was saved in 90.1%. Post-radiation optical retinopathy developed in 9.3% of cases, progression of retinal detachment was registered in 13.9% of cases. The one-year metastatic-free survival rate was 96.3±3.6%, the two-year survival rate was 81.3±8.6%.Conclusions. In the present study, the use of stereotactic radiosurgery with a prescribed marginal dose of up to 35 Gy allowed achieving sustainable local control of primary choroidal melanoma cT1–3 in 100% of cases over a median follow-up period of 16 months.

Thiazolo[2, 3-f]purine derivatives and their analogs – dihydrothiazolo[2, 3-f]purine, 7-(thietan-3-yl)purine, and 8-(2-hydroxypropylthio)purine derivatives – were synthesized. The compounds synthesized here had no effects on protein glycation reactions using glucose; they gave weak inhibition of glycogen phosphorylase; they had no hemorheological activity. Substances with hypotensive activity greater than that of Dibazol were found. A number of substances had hypoglycemic effects greater than those of chlorpropamide and Adebit. Two compounds inhibited dipeptidylpeptidase-4, but were less active than reference agent vildagliptin.

We studied the effects of GABA derivatives on anxious and compulsive behavior of progeny of rats with experimental preeclampsia provoked by replacement of drinking water for 1.8% NaCl solution from the first day of pregnancy to delivery. In comparison with progeny of health rats, the offspring of dams with complicated pregnancy demonstrated high level of anxiety and the development of obsessive-compulsive disorder both at the early (40 and 70 days) and late (6 and 12 months) stages of ontogeny. GABA derivatives succicard, salifen, and phenibut reduced symptoms of experimental preeclampsia in offspring of various age by decreasing the level of anxiety and reducing compulsive behavior. The efficacy of the examined derivatives was similar to that of the reference drug Pantogam.

Condensation of 1-substituted 2-aminobenzimidazoles with aromatic aldehydes produced the corresponding azomethines, reduction of which by sodium borohydride afforded 1-substituted 2-benzylaminobenzimidazoles. The Microcosm information technology (IT) tool was used to assess in silico the potential for antiarrhythmic, antiaggregant, antioxidant, hemorheologic, and antiglycating activity in this series of compounds. Pharmacological screening identified which of the synthesized compounds were active. It was shown that the computer predictions correlated with the experimental data.

Platelet aggregation was assessed by the method of G. Born modified as described by Z.A. Gabbasov. Blood viscosity was measured using an AKR-2 rotating-type viscometer - rheological blood analyzer at six shear rates (10 s-1, 20 s-1, 50 s-1, 100 s-1, 200 s-1, and 300 s-1) simulating different intensities of the blood flow through the vessels. The model of arterial thrombosis induced by electrical current was constructed based on the method of G. Guglielmi et al (1991). Gliclazide was used in the studies of Limiglidol antiaggregant and antithrombotic properties and pentoxifylline in the studies of the influence of Limiglidol on rheological blood properties. It was shown that Limiglidol inhibited platelet aggregation and prolonged the time of thrombus formation. It proved to be superior to gliclazide in terms of these activities and reduced blood viscosity to a higher degree than pentoxifylline.

Opening of the oxirane ring in 1-oxiranylmethylindoles yielded new indole derivatives containing 1,2-amino alcohol residues at the nitrogen atom. Compounds were studied in vitro in relation to various types of pharmacological activity typical of this class of compounds, including receptor (5-HT2, 5-HT3, P2Y1-ergic, κ-opioid), antiaggregant, hemorheological, antiarrhythmic, and antioxidant activities.

Opening of the five-member ring of indolylmethyleneoxazolones with aliphatic amines was used to synthesize a series of amides of 2-amino-3-indolylacrylic acid. These compounds were studied in vitro in relation to the various types of pharmacological activity typical of this class, including receptor (5-HT2-, 5-HT3-, and P2Y1-ergic, K-opioid), antiaggregant, hemorheological, antiarrhythmic, and antioxidant activities.

A series of 3-(N,N-disubstituted)acetamide-1-R-2-aminobenzimidazolium chlorides were synthesized. Their pharmacological properties were studied. It was established that the synthesized substances decreased platelet aggregation and possessed antioxidant and antiarrhythmic activity. Some of the compounds produced a hypoglycemic action and exhibited antagonistic activity with respect to serotonin 5-HT2 receptors.

The synthesis of 10-chloroethyl-2,3,4,10-tetrahydropyrimido[1,2-a]benzimidazole was described. The nucleophilic substitution of the chlorine atom by various amines was studied. As a result, 10-alkylaminoethyl-substituted derivatives of this tricycle containing alkylamines and 4-substituted piperazines were obtained. These compounds exhibited 5-HT2 antagonist activity; platelet antiaggregant properties; and moderate P2Y1-antagonist, antiarrhythmic, and hypoglycemic action.

Taking into account the structure—activity relationship established previously for imidazobenzimidazole derivatives with high hemorheological activity, several new 9-R-2-halogenophenyl-substituted imidazo[1,2-a]benzimidazoles with C2 fluoro-, chloro-, dichloro-, or bromo-phenyl radicals have been synthesized. All substances were tested in vitro for various types of pharmacological activity characteristic of this class of drugs including hemorheological, antiplatelet, antiarrhythmic, antioxidant; 5-HT2-, 5-HT3-, P2Y1-, and H1-antagonist; and κ-opioid-agonist.

In continuation of the investigation of 1-dialkylaminoethyl-2,3-dihydroimidazo[1,2-a]benzimidazoles demonstrating serotoninergic activity, several new substances of this class with 4-substituted piperazines and piperidines as amine moieties were synthesized and tested pharmacologically in vitro. All substances were investigated for antiserotoninergic, antiplatelet, haemorheological, antiarrhythmic, and antioxidant activity.

New water-soluble 3-acetyl-2-R-9-dialkylaminoethylimidazo[1,2-a]benzimidazoles were synthesized on the basis of previously described structure-effect relationships among imidazobenzimidazole derivatives with high levels of hypotensive activity. All these compounds were studied in vitro in terms of a variety of types of pharmacological activity characteristic for this class of compounds, including antiarrhythmic, antiaggregant, antioxidant, hemorheological, K-opioid agonistic, hypotensive, spasmolytic, and adrenoblocking activities; their effects on cAMP phosphodiesterdase activity and physical exercise tolerance were also studied.

The main function of Csk tyrosine kinases is phosphorylation of the C-terminal part of Src tyrosine kinases as a mechanism of their downregulation. A decrease in the expression of csk gene results in the enhancement of Src tyrosine kinase activity. In this study, cDNA containing the full coding sequence of the human leukocyte Csk tyrosine kinase gene has been cloned. The protein encoded by a 1624-bp cDNA fragment has 99% homology to human Csk tyrosine kinase. A comparative sequence analysis of full-length cDNAs for Csk tyrosine kinase of normal lymphocytes and lymphocytes of patients with choroidal melanoma revealed a nucleotide substitution in exon 10 of the gene, which appears to be of diagnostic significance. It has been shown that the risk of choroidal melanoma correlated with the frequency of this allele.

Tyrosine kinases of the Csk family play an important role in cell growth regulation and normal cell differentiation. They are also involved in carcinogenesis as oncoproteins. The main function of these tyrosine kinases is phosphorylation of tyrosine kinases of the Src family at their C-terminal regions to negatively regulate their activity. Disturbance of csk expression increases the Src tyrosine kinase activity. The full-length coding sequence of the csk cDNA was cloned from human lymphocytes. The 1624-bp cDNA consists of 12 exons and encodes a protein that has conserved SH2 and SH3 domains and is similar to human Csk tyrosine kinase by 99%. The full-length cDNA can be used to analyze the csk structure in normal or illdefined human cells.

The synthesis and pharmacological properties of a series of aroylmethyl derivatives of tricyclic benzimidazole systems containing hydroxy groups in aroyl radicals are described. It is established that most of the synthesized compounds exhibit a high antioxidant activity, possess pronounced hemorheological properties, and influence the blood glucose level.

Oxidation of 1-ethyl- and 1-propyl-8-bromo-3-methyl-7-(thietan-3-yl)xanthines was used to synthesize 8-bromo-substituted 1-alkyl-3-methyl-7-(1-oxothietan-3-yl)xanthines, with yields of 49 – 52%; these were used to synthesize 8-amino-substituted 1-alkyl-3-methyl-7-(1-oxothietan-3-yl)xanthines, with yields of 14 – 87%. Piperidine, morpholine, monoethanolamine, and trisamine were used as reagents. The structures of the substances were established by IR and 1H NMR spectroscopy. The compounds synthesized here were found to have marked antiaggregant activity.

We studied the impact of compounds RU-1202 and SUM-55 on electrophoretic mobility of "young" and "old" erythrocytes fractionated in a density gradient. The test compounds are shown to increase electrophoretic mobility of erythrocytes, compound SUM-55 being superior to the reference drug pentoxifylline.

A series of 8-amino-substituted 1-alkyl-3-methyl-7-(thietanyl-3)xanthines have been synthesized using 1-ethyl-, 1-propyl-, and 1-hexyl-8-bromo-3-methyl-7-(thietanyl-3)xanthines and various reactants including monoethanolamine, tris-amine, and piperazine. The target 8-amino-substituted 1-alkyl-3-methyl-7- (thietanyl-3)xanthines were obtained in 54 - 88% yields. The structures of the synthesized compounds were determined using IR spectroscopy and PMR spectrometry. Most of the synthesized compounds exhibit antiaggregant activity.

Reactions of 3,5-dibromo-1,2,4-triazoles containing thietane or thietane-1,1-dioxide with thioglycolic acid yielded 2-[1-(thietanyl-3)-or 2-[1-(1,1-dioxothietanyl-3)-3-bromo-1,2,4-triazolyl-5-thio]acetic acids. Their salts have also been synthesized via reactions with amines and alkalis. Evaluation of the rheological properties showed that some of the synthesized compounds exhibited antiaggregant activity with respect to erythrocytes that was comparable with the effect of pentoxifylline.

Influence of a new xanthine derivative SUM-55 on microrheological properties erythrocytes in rats with experimental diabetes has been investigated. It is shown that compound SUM-55 significantly reduces aggregation and increases deformability of erythrocytes. Comparative analysis showed that SUM-55 is comparable with pentoxyphylline in the ability to reduce aggregation of erythrocytes and is superior to the reference drug in increasing deformability of red bloodcells.

The main function of Csk tyrosine kinases is phosphorylation of the C-terminal part of Srk tyrosine kinases as a mechanism of their downregulation. A decrease in the expression of csk gene results in the enhancement of Srk tyrosine kinase activity. In this study, cDNA containing the full coding sequence of the human leukocyte Csk tyrosine kinase gene has been cloned. The protein encoded by a a 1624-bp cDNA fragment has 99% homology to human Csk tyrosine kinase. A comparative sequence analysis of full-length cDNAs for Csk tyrosine kinase of normal lymphocytes and lymphocytes of patients with choroidal melanoma revealed a nucleotide substitution in dexon 10 of the gene, which appears to be of diagnostic significance. It has been shown that the risk of choroidal melanoma correlated with the frequency of this allele.

Extracts of Gymnemy sylvestre (GS) exhibit hemorheological activity. The most pronounced effect was observed for GL extract in 25 wt % concentration, which (i) induced a decrease in the viscosity of blood and washed erythrocyte suspensions in the entire range of shear rates by a factor of 1,3 (ii) reduced the degree of deformability of red blood cells, (iii) increased the degree of osmotic resistance of erythrocytes by 21.3%, (iv) increased the intensity of fluorescence of DSM+ probe in erythrocyte suspensions by a factor of 1.5, and (v) decreased the degree of anisotropy, thus generally improving the viscoelastic properties of the erythrocyte membrane and preventing the thrombocyte aggregation. In this respect, the GS extract activity exceeded that of Tanakan.

Tyrosine kinases of Csk family play important role in the cell growth regulation and normal cell differentiation and also can participate in the process of cancer genesis as oncoproteins. The main function of these tyrosine kinases is the phosphorylation of the Src family tyrosine kinases at their carboxyl terminus, which is the basis of their activity negative regulation. The disturbance of the csk gene expression leads to the increase of the Src tyrosine kinase activity. We have cloned a full-length encoding cDNA of the tyrosine kinase csk gene of human lymphocytes. 1.6-kilobase cDNA encodes the protein, which consists of 12 exons with conserved SH2 and SH3 domains. The homology between this protein and human Csk tyrosine kinase is 99%. A full-length DNA-copy of human lymphocytes RNA can be used for the analysis of csk gene structure in normal and pathologically changed human cells.