Molecular modeling as a new approach to the development of urokinase inhibitors.

Proteolytic activity of urokinase plays an important role in negative remodeling of blood vessels, restenosis, tumor angiogenesis, and metastasizing, which necessitates the development of selective urokinase inhibitors. Using methods of computer modeling (docking, post processing, and direct docking) and quantum chemistry, we selected substances from the large compound database, analyzed their structures, and experimentally verified their inhibitor activity. New urokinase inhibitor candidates were proposed based on the theoretical predictions and experimental verification of compound activities. The process of modifying urokinase inhibitors based on (benzothiazol-3-yl)guanidine was developed. A new urokinase inhibitor (5-brom-benzothiazol-3-yl)guanidine, that can be effective for regulation of vascular remodeling and tumor angiogenesis, was created.

Proteolytically inactive recombinant forms of urokinase suppress migration of endothelial cells.

Proteolytically inactive recombinant forms of urokinase (uPAHQ and amino-terminal fragment) inhibit spontaneous migration of endothelial cells; amino-terminal fragment also suppresses angiogenesis stimulated by basic fibroblast growth factor in vitro. These findings suggest the possibility of using synthesized proteolytically inactive recombinant forms of urokinase for the regulation of endothelial cell migration and suppression of neoangiogenesis.

[Analysis of morpho-functional parameters of the heart and polymorphisms of Renin-Angiotensin-aldosterone system genes in patients with different variants of the course of hypertrophic cardiomyopathy].

BACKGROUND: Clinical course and prognosis of a hereditary myocardial disease hypertrophic cardiomyopathy (HCMP) is determined by multiple factors most of which have genetic nature. AIM: To study morpho functional parameters of the heart and polymorphisms of renin angiotensin aldosterone system genes in patients with various variants of the course of HCMP: stable variant (18%), atrial fibrillation (20%), progressing variant (51%), sudden cardiac death (9%) and "terminal stage" of disease (2%). Control group comprised 55 healthy people (mean age 44.6 +/- 10.3 years, =0.43). All patients went through examination which included molecular genetic and instrumental methods of investigation. RESULTS: In the group of patients with progressing course we observed most frequent development of ECG changes characteristic of HCMP as well as asymmetrical myocardial hypertrophy caused by obstruction of LVOT. In the group of patients with variant "atrial fibrillation" we revealed increase of duration of P wave on ECG, development of more pronounced left atrial dilation and diastolic dysfunction. We established that presence of HCMP was associated with I/D polymorphism of gene and 1166/ polymorphism of AGTR1 gene. Unfavorable combination of allele variants of polymorphisms of RAAS genes exerts cumulative effect on phenotype of the disease and is associated with development of pronounced hypertrophy of the myocardium. The structure of hereditary susceptibility to development of stable variant of the disease course in patients with HCMP includes allele variants of -344 / polymorphism of CYP11B2 gene and 235 polymorphism of AGT gene. Development of the variant with atrial fibrillation is associated with allele variants of 1166/ polymorphism of AGTR1 gene and of the variant with progressing course - with I/D polymorphism of gene and -1903 A/G polymorphism of CMA1 gene.

[Genetic factors of risk of ischemic heart disease development in patients with familial hypercholesterolemia].

UNLABELLED: Ischemic heart disease (IHD) develops in patients with familial hypercholesterolemia (FHC) 15-20 years earlier than in general population. However age of onset of the disease, its clinical manifestations are variable and not completely determined by cholesterol level and class of low density lipoprotein receptor mutations. AIM: To elucidate associations of some auxiliary genetic factors -- such as C151565T, C677T, R353Q polymorphisms of glycoprotein IIIa (GPIIIa), methylenetetrahydrofolate reductase (MTHFR) and coagulation factor VII genes, respectively, -- with the presence of IHD in patients with FHC. MATERIAL: Patients with clinical diagnosis of heterozygous FHC (n=198) with (n=106) and without (n=92) IHD. RESULTS: Patients with compared with those without IHD had similar frequency of T-allele of MTHFR gene (p=0.519), more often had T-allele of GPIIIa gene (23 and 12.5%, respectively, p=0.009), and less often -- Q-allele of factor VII gene (13 and 21%, respectively, p=0.048). Multifactorial analysis showed that risk of IHD was higher in patients with TT compared with CC genotype of the GPIIIa gene (OR 1.53, 95%CI 1.12-2.3), and lower in patients with RQ and QQ compared with RR genotype of factor VII gene (OR 0.41, 95%CI 0.19-0.75). CONCLUSION: In patients with FHC polymorphisms in factor VII and GPIIIa genes but not C677T polymorphism of MTHFR gene were associated with the presence of IHD.

[The role of mutation in cardiac beta-myosin heavy chain gene in population of patients].

One of most widely spread causes of hypertrophic cardiomyopathy (HCMP) is mutation in cardiac beta-myosin heavy chain gene. Data on contribution of this mutation to development of HCMP in Russian patients are very limited. We conducted screening of beta-myosin heavy chain gene for the presence of mutations in 116 patients with confirmed HCMP (probands). DHPLC was used with subsequent sequencing of DNA fragments. Genetic defects of beta-myosin heavy chain were found more than in every 10-th patient. These defects were represented by 13 mutations (Ala729Pro mutation was found twice). Phenotypes of majority of known mutations in Russian population did not differ substantially from their phenotypes in other populations. Six mutations had not been previously described; most of them were associated with especially severe clinical and hemodynamic signs and relatively unfavorable course of the disease. Thus beta-myosin heavy chain gene mutation play important role in etiology of HCMP in patients in Russia.

[Low density lipoprotein receptor gene mutations in patients with clinical diagnosis of familial hypercholesterolemia.]. / Mutatsii gena retseptora lipoproteinov nizkoi plotnosti u patsientov s klinicheskim diagnozom semeinoi giperkholesterinemii.

UNLABELLED: Low density lipoprotein receptor (LDLR) gene mutations cause familial hypercholesterolemia which is associated with elevated risk of ischemic heart disease. AIM: To define LDLR gene mutations in unrelated patients with heterozygous familial hypercholesterolemia in Russia. METHODS: PCR- single-strand conformation polymorphism analysis, automated DNA sequencing, and test for the presence of the apolipoprotein (apo) B-3500 mutation known to induce hereditary defect in apo-B-100. RESULTS: We found 6 novel mutations of LDLR gene designated E8X, 230insG, 671_679dupGACAAATCT, W422R, D461Y, and V698L. We also identified three missense mutations - C139G, E207K and R395W, which were previously described in FH patients from western populations. None of the studied persons had apo-B-3500 mutation. CONCLUSION: These findings broaden knowledge on mutations responsible for development of familial hypercholesterolemia and confirm molecular heterogeneity of this disease in Russia.

[Multiple molecular-genetic defects in a woman with mixed hyperlipoproteinemia and early ischemic heart disease]. / Mnozhestvennye molekuliarno-geneticheskie defekty u zhenshchiny so smeshannoi formoi giperlipoproteinemii i rannei ishemicheskoi bolezn'iu serdtsa.

AIM: Analysis of genes of apolipoprotein E (apoE), LDLP receptor and methylentetrahydrofolate reductase (MTHFR) in a female patient with mixed hyperlipoproteinemia (HLP) and early ischemic heart disease (IHD). MATERIAL AND METHODS: A patient with a mixed form of HLP and 5 her relatives were examined genetically. The genotype of apoE and MTHFR was determined using a restrictive analysis of PCR fragments. Conformation of one chain DNA was used to analyse gene of LDLP-receptor with following sequencing of anomalous DNA. RESULTS: The proband had changes in all examined genes: nucleotide replacement of A370T gene of LDLP receptor, nucleotide replacement of MTHFR gene C677T and epsilon 2/epsilon 2-genotype of apoE. None of the relatives carried more than one polymorphism by the studied genes. CONCLUSION: Early IHD in females can be caused by combination of polymorphisms of genes associated with development of atherosclerosis.

[Antibodies against synthetic peptide fragments of T-cadherin inhibit binding of low density proteins with T-cadherin]. / Antitela protiv sinteticheskikh peptidnykh fragmentov T-kadgerina podavliaiut sviazyvanie lipoproteidov nizkoi plotnosti s T-kadgerinom.

Potential antigenic determinants of the atypical lipoprotein-binding proteins T-cadherin (p105) and its precursor (p130) from cells of human smooth muscles were synthesized by the solid phase method according to the Fmoc-scheme. These corresponded to the 51-61, 140-160, 161-179, 260-271, 340-352, 350-362, and 370-385 sequences of p130 and were chosen on the basis of computer analysis of its antigenic structure. The conjugates of the peptides with horseradish peroxidase were used for the immunization of mice and rabbits. Antisera against the peptides corresponding to the 140-160, 161-179, and 260-271 sequences of p105 were shown by immunoblotting to react with p105, which we isolated from the vascular cells of smooth muscles and earlier identified as T-cadherin. These antisera inhibited the binding of low density lipoproteins with p105 in a dose-dependent manner. These results confirmed the identification of the p105 protein as T-cadherin and demonstrated the fundamental possibility of studying the interaction of this protein with low density lipoproteins by using antipeptide antibodies that inhibit binding.

[Novel lipoprotein-binding proteins p105 and p130 in smooth muscles of human vessels: structure, expression, and possible physiological role]. / Novye lipoproteid-sviazyvaiushchie belki p105 i p130 v gladkomyshechnykh kletkakh cheloveka: struktura, ékspressiia i vozmozhnaia fiziologicheskaia rol'.

The expression level of two new lipoprotein-binding proteins p105 and p130 was maximal in inactive VSMC and could be suppressed by activators of proliferation. Both proteins were detected by antisera against three synthetic fragments of T-cadherin and were rendered soluble by GPI-specific phospholipase C. The findings suggest that the 105 kDa lipoprotein-binding protein is T-cadherin whereas p130 is a partially processed GPI-anchored precursor of T-cadherin.

[Atypical binding sites of low density lipoproteins in human vascular smooth muscle cells]. / Atipichnye uchastki sviazyvaniia lipoproteidov nizkoi plotnosti v gladkomyshechnykh kletkakh sosudov cheloveka.

Lipoprotein-binding sites on cultured human omental vascular smooth muscle cells have been investigated. Two sites specifically binding low density lipoprotein (Kd1 = 1 microgram/ml and Kd2 = 50 micrograms/ml) were found. The properties of the high affinity site are similar to those of the previously described "classical" apo B,E-receptor. The nature of the second site is not clear. Binding to this low affinity site is saturable at physiological concentrations of LDL, is reversible and demonstrates a significant selectivity for LDL as compared to HDL3. In contrast with the apo B,E-receptor, the interaction of LDL with the low affinity site is not heparin-sensitive, does not require the presence of bivalent cations and is not abolished after modification of lysine residues of apo B. The kinetic characteristics of the LDL interaction with the low affinity site are in good correlation with the parameters of activation of second messenger systems. The Kd2 value of LDL binding is close to the LDL concentration inducing a half-maximal elevation of inositol phosphates and cytoplasmic Ca2+ level. Acetylation or carbamylation of apo B does not influence the ability of LDL to activate cell-signalling systems. Also, LDL-induced activation of the phosphoinositide turnover is not sensitive to heparin and EDTA. The data obtained support the hypothesis that the low affinity LDL-binding site mediates lipoprotein-induced activation of second messenger systems in human vascular smooth muscle cells.