[Fatty acid composition in the carotid artery tissue in the atheromatosis and lipid spot areas. Universal pathogenesis of the atherosclerosis syndrome and its symptom of intimal atheromatosis].

Gas chromatography with mass spectroscopy detection have shown that the major components of atheromatous masses in formed atherosclerotic plaques (surgery material) are the derivatives of essential polyenic fatty acids (ES poly-FA) and of the alcohol cholesterol. They undergo nonphysiological catabolism (hydrolysis) in the lysosomes of resident macrophages as components of protein macromolecules, low-density lipoproteins (LDL). In excess of palmitic triglycer- ides apoB-100 of LDL does not form ligand, and ligand-free LDL become biological in the circulation. They are uptaken via scavenger receptors by resident macrophages in the intima. When ligand LDL are physiologically uptaken via apoB-receptors, they are catabolized (oxidized) in peroxisomes but not in lysosomes. Lipid spots result from functional cellular lipoidosis which fulfills the biological reaction of inflammation and initiate the lipoidosis--vector protein for FA transport--C-reactive protein pathway. Formation of ligand-free LDL lays the basis for intracellular ES poly-FA deficiency and clinical manifestations of the atherosclerosis syndrome. Intima is the spot where large-molecular-weight (> 70 kD) biological rubbish is collected and utilized from a local intravascular pool of the intercellular medium.

A cytofluorometric study of membrane rafts in human monocyte subsets in atherosclerosis.

The peripheral blood monocytes of atherosclerotic patients are pre-activated and have some of the features of tissue macrophages. Their adhesion to the endothelium is 1.5 times higher than that of monocytes from healthy subjects, and they express a number of receptors and antigens typical of tissue macrophages. Additionally, earlier we showed that the biosynthesis of gangliosides, whose main function is the formation of membrane rafts, is significantly activated in blood monocytes from atherosclerotic patients, as well as during the in vitro differentiation of normal monocytes into macrophages. In this study, we investigated the expression of membrane rafts on various monocyte subsets from healthy subjects and atherosclerotic patients. Based on flow cytometry results, the monocytes in the examined atherosclerotic patients were found to differ from those in healthy subjects by a twofold increase in the proportion of the intermediate subset (CD14(++)/CD16(+)) and by enhancement in the expression of the fractalkine receptor CX3CR1 on the intermediate and non-classical subsets (CD14(++)/CD16(+) and CD14(+)/CD16(++)) (2.3 and 1.8 times, respectively). This suggests a pre-activated state of monocytes in atherosclerotic patients. At the same time, the expression of the membrane raft marker on the monocyte subsets was similar in both studied groups. However, a study of the in vitro differentiation of monocytes into macrophages showed that the membrane raft expression increased 2 times as early as on the 1st day of culturing and 3 times on the 7th day compared to that in freshly isolated monocytes. Therefore, it is suggested that monocytes in atherosclerosis accumulate gangliosides that are used to form membrane rafts during the macrophage differentiation after the migration of monocytes into the arterial intima.

[Possibilities of instrumental methods of diagnosis of unstable atherosclerotic plaques of carotid arteries].

Today there exists a wide variety of laboratory and instrumental methods aimed at diagnosing an unstable carotid aortosclerotic plaque. Assessment of the laboratory indices is not sufficiently effective since it does not allow of revealing the fact of the formation of an unstable plague at early stages and to determine its localization. The instrumental methods employed (ultrasonographic study, magnetic resonance imaging, multiplanar computed tomography, positron emission tomography) were focussed on detecting pathomorphological markers of instability - thickness of the fibrous coating, structural plaques, the presence of erosions, ulcerations, haemorrhages, calcifications, lipid nucleus, activity of the cellular processes inside the plaque. The revealed signs promote early diagnosis of unstable atherosclerotic plaque with the determination of its localization. Nevertheless, they do not provide evidence about the danger of its rupture, whereas the overwhelming majority of acute vascular catastrophes including acute impairments of cerebral circulation is directly associated with arterial thrombosis resulting from rupture of the atherosclerotic plaque. Therefore, search for new methods aimed at prediction of complications of the atherosclerotic plaque which would be employed in routine clinical practice still remain urgently important today. The most promising is the study of the state of the atherosclerotic plaques of carotid arteries for prediction of acute impairment of cerebral circulation.

[Comparison of morphological features of carotid arteries atherosclerotic plaques with clinical-instrumental data in symptomatic and asymptomatic patients with severe carotid atherosclerosis].

A complex histomorphometric and clinical-instrumental analysis of atherosclerotic lesions of the carotid arteries obtained during carotid endarterectomies (CEE) of patients with hemodynamically significant stenoses was conducted. Two groups of patients were compared: symptomatic, which earlier underwent cerebral vascular accident (CVA) or transitory ischemic attacks (TIA), and asymptomatic ones with no complications of the disease. Statistical analysis of clinical and laboratory data showed no significant differences between two groups except for the level of lipoprotein(a) [Lp(a)] in the blood plasma, which was higher (p<0.05) in asymptomatic patients compared with symptomatic ones. Statistical analysis of carotid arteries ultrasound duplex scanning (USDS) in the preoperative period did not reveal significant differences in the degree of maximum vessels stenosis between the compared groups of patients. Surface defects of atherosclerotic plaques (ASP) were shown to be significantly more common (p<0.05) in the group of symptomatic patients compared with asymptomatic ones. According to histological analysis 88% of extracted ASP was unstable in symptomatic patients and 77% of ASP - in asymptomatic patients. This may indicate high risk of CVA/TIA in both groups of patients. Statistical evaluation of magnetic resonance tomography (MRT) and USDS techniques in comparison with abilities of the most reliable histological analysis showed that both non-invasive diagnostic methods are highly sensitive in detecting unstable ASP, though MRT showed higher level of specificity compared with USDS.

Morphometric analysis of atherosclerotic plaques in human carotid arteries.

Morphometric analysis of 35 biopsy specimens from patients with stable (n=10) and unstable (n=25) atherosclerotic lesions was carried out. The structure of the plaques and their connective tissue caps was studied by various methods of histological sections staining. A new morphometric approach to quantitative evaluation of atherosclerotic lesions instability is suggested. It consists in calculation of the morphological "rigidity" coefficient, due to which the plaque is characterized more accurately. The proportion of areas of the "rigid" (connective tissue and calcium salt deposition areas) to "soft" (atheronecrotic nuclei, microvessels, clots and hemorrhages) structures of the plaque is evaluated. Plaque instability (liability of a to rupture) is associated with changes in the extracellular matrix components in the cap: accumulation of collagen and reduction of elastic fiber content reducing vessel elasticity and making its locally more rigid.

[In vitro accumulation of the photosensitizer Photosens in the atherosclerotic plaque of the human carotid artery].

The investigation was undertaken to study the accumulation of the photosensitizer Photosens in arterial atherosclerotic plaques and to immunohistochemically identify cellular elements in them. Specimens were obtained during carotid endarterectomy. The preferential accumulation of Photosens occurred in the plaque areas containing the largest number of cells, such as macrophages and lymphocytes. The photosensitizer accumulated to a greater extent in the unstable plaques than in the stable ones, which seems to be associated with the more marked infiltration of unstable plaques by the cells involved in the inflammatory reaction.

Effects of photodynamic exposure on endothelial cells in vitro.

Experiments on cultured human umbilical vein endotheliocytes showed that accumulation of photosensitive dye (aluminum phthalocyanin; PHOTOSENSE) in cells and laser exposure alone were inessential for the viability of endothelial cells. Contrary to this, exposure of the cells which have accumulated aluminum phthalocyanin (an average of 111.1 ng/mg protein) to low-intensity laser (λ=675 nm) led to a dose-dependent reduction of endotheliocyte viability. Hence, cultured endothelial cells can be used for screening of various photosensitizers and preliminary optimization of photodynamic therapy.

[Comparative transcriptome analysis of human aorta atherosclerotic lesions and peripheral blood leukocytes from essential hypertension patients].

One of the major cardiovascular risk factor which predisposes to and accelerates atherosclerosis is arterial hypertension (AH). To determine the molecular basis of the crosslink between AH and atherosclerosis for the development of new treatment strategies large-scale transcriptome analysis of the cells implicated in atherogenesis is needed. We used cDNA microarray technique for simultaneous analysis of gene expression in human abdominal aorta normal sites and atherosclerotic lesions of different histological types, as well as in peripheral blood leukocytes from patients with essential hypertension (EH) and donors. The microarray data were verified by quantitative RT-PCR (reverse transcription coupled with polymerase chain reaction) and immunohistochemical analysis. Differential expression of 40 genes has been found, among which twenty two genes demonstrated up-regulation and 18 genes demonstrated down-regulation in atherosclerotic aorta compared with normal vessel. New gene-candidates, implicated in atherogenesis, have been identified - FPRL2, CD37, CD53, RGS1, LCP1, SPI1, CTSA, EPAS1, FHL1, GEM, RHOB, SPARCL1, ITGA8, PLN, and COL14A1. These genes participate in cell migration and adhesion, phenotypic changes of smooth muscle cells, immune and inflammatory reactions, oxidative processes and extracellular matrix remodeling. We have found increased expression levels of CD53, SPI1, FPRL2, SPP1, CTSD, ACP5, LCP1, CTSA and LIPA genes in peripheral blood leukocytes from EH patients and in atherosclerotic lesions of human aorta. The majority of these genes significantly (p<0.005) positively (r>0.5) correlated with AH stage as well as with histological grading of atherosclerotic lesions.

[Detection of bone marrow-derived cells in neointimal thickening in the rat carotid artery by nested polymerase chain reaction].

The bone marrow origin of cells involved in neointimal formation after injury of the luminal surface of the vessel was confirmed by highly sensitive nested polymerase chain reaction on isolated vascular wall cells. The model of intimal hyperplasia after balloon angioplasty of the carotid artery in radiation bone marrow chimeras between male and female Wistar rats was used. The Y chromosomes of rat male donors of the bone marrow for irradiated females were used as a marker of bone marrow-derived cells. This approach demonstrated a bone marrow origin of a large fraction of alpha-actin-positive (smooth muscle) neointimal cells.

Activation of ganglioside GM3 biosynthesis in human monocyte/macrophages during culturing in vitro.

We found that GM3 levels in human peripheral blood monocytes and cultured monocyte-derived macrophages were 0.37 and 2.7 microg per million cells, respectively. GM3 synthase of monocytes and to a greater extent of monocyte-derived macrophages was shown to be able to sialylate endogenous substrate, lactosylceramide (LacCer), to form GM3. With exogenously added LacCer, GM3 synthase activity was 57.1 and 563 pmol/h per mg protein in monocytes and monocyte-derived macrophages, respectively. The revealed changes in ganglioside GM3 biosynthesis are specific as the activity of some other sialyltransferases under these conditions was not altered. Human anti-GM3 synthase antibody detected in monocytes a main protein with molecular weight of 60 kD and minor proteins with molecular masses of 52 and 64 kD. In monocyte-derived macrophages the amounts of 60 kD protein and especially 64 kD protein sharply rose. Thus, the increase in ganglioside GM3 levels, GM3 synthase activity, and the enzyme amounts during culturing of monocyte/macrophages may be one of the mechanisms of in vivo increased ganglioside GM3 levels in arterial atherosclerotic lesions.

Lentivirus transduction of bone marrow hemopoietic precursor cells with Lin-c-kit+ phenotype ex vivo using a genetic construct containing green fluorescent protein gene.

We developed a technology of labeling bone marrow precursor cells with the Lin-c-kit+ phenotype in culture by green fluorescent protein gene using a lentivirus vector. The proposed system provides effective transduction of bone marrow precursor cells and high transgene expression level in vitro (27%). The integration of the transgene into the transduced cell genome in vivo was verified by the method of splenic colonies.

[Expression of urokinase plasminogen activator, its receptor and plasminogen activator inhibitor type 1 in different types of atherosclerotic lesion in human aorta]. / Ekspressiia urokinazy, ee retseptora i ingibitora aktivatorov plazminogena 1-go tipa v stenke aorty cheloveka pri raznykh tipakh ateroskleroticheskogo porazheniia.

The role of plasminogen activators in the regulation of key processes of atherosclerosis progression stays unclear. The aim of this study was to evaluate the expression of urokinase plasminogen activator (uPA), its receptor (uPAR) and the plasminogen activator inhibitor type 1 (PAI-1) in human aorta, and to balance them with the stage of atherosclerotic lesion. We have shown that uPA and uPAR in normal aorta are mostly expressed by intimal smooth muscle cells. The expression of these proteins was up-regulated in diseased aorta compared to normal artery. The most part of cells in both fatty streak and fibro-fatty lesion were monocytes/macrophages, and about 60% of these cells expressed uPA and its receptor. PAI-1 was mostly localized on the lumonal part of the aorta and in the extracellular matrix of the intima. We observed a moderate increase of PAI-1 expression in atherosclerotic lesion. Thus, our data indicate participation of plasminogen system in atherogenesis.

[A new concept of development of neointimal hyperplasia]. / Novaia kontseptsiia razvitiia giperplazii intimy sosudov.

The intima hyperplasia is a major morphological feature of various arterial pathologies such as atherosclerosis, postangioplasty restenosis and transplantation arteriopathy. It is commonly assumed that smooth muscle cells (SMC) comprising loci of the intima hyperplasia originate from arterial media. However, recent studies suggest that the bone marrow could also supply circulating vascular progenitor of SMCs and endothelial cells (EC). Such bone marrow progenitors participate in the formation of a cellular mass of neointima after experimental allotransplantation, mechanical vessel injury or hyperlipidemia induced experimental atherosclerosis. Circulating SMC and EC progenitors are also likely to be involved in the transplantation arteriopathy development in humans but their roles in the atherosclerosis and restenosis remain to be determined. Stages of the mobilization, defferentiation and proliferation of SMC progenitors could provide point of attack for new therapeutic strategies for the treatment of proliferative vascular diseases. The precise understanding of the neointima cells origin could provide a key for development of the optimal therapeutic strategy of treatnent of such disorders. This review is focused on the pathological significance of circulating progenitors of the bone marrow origin, particularly on the SMC progenitors, for development of vascular wall disorders.

[Expression, regulation, and pathophysiological role of NAD(P)H oxidases in atherogenesis]. / ékspressiia, reguliatsiia i rol' NAD(P)H-zavisimykh oksidaz v aterogeneze.

Oxidative stress has been implicated in the development and progression of atherosclerotic lesions. Significant increase of reactive oxygen species production by vascular cells can lead to progression of atherosclerotic lesions and development of unstable plaques due to triggering the apoptosis of endothelial and smooth muscle cells, expression of matrix metalloproteases and inflammatory cytokines. Cytolysis NAD(P)H-dependent oxidases appeared to be involved in reactive oxygen species production in the vascular network. Understanding of functions and regulation of individual NAD(P)H oxidases in atherosclerotic lesions can facilitate the development of novel therapeutic strategy for treating atherosclerosis. This review summarizes current data regarding expression, regulation and pathophysiological significance of these enzymes during development and progression of human atherosclerotic lesions.

[The origin of neointimal cells in the rat carotid artery after balloon angioplasty]. / Proiskhozhdenie kletok neointimy, obrazovannoi v sonnykh arteriiakh krys, posle ballonnoi angioplastiki.

At present the issue of a possible role of circulating stem cells and precursors in pathological vascular wall remodeling after angioplasty remains unsolved. Therefore the origin of neointimal cells was examined in the rat carotid artery after balloon angioplasty using morphological and immunocytochemical approaches. It is shown that at the early stages (1-7 days) after vessel injury acute inflammatory response arises in the arterial wall recruiting neutrophils, monocytes, macrophages as well as large amounts of low-differentiated blood-derived cells. At the late stages (10-28 days), at the area of injured intima, a new hyperplastic intima (neointima) is formed, which consists of cells carrying specific smooth muscle markers--alpha-actin and smoothelin. The study on cell proliferative behaviour in the injured vessel wall by bromodeoxyuridine showed that in the process of neointima formation blood-born rather than resident cells are involved. Probably, early smooth muscle and endothelial precursor cells penetrate into injured area with blood stream, where they proliferative and differentiate into mature cells.

[Phenotypes of smooth muscle cells in carotid arteries in Takayasu's disease]. / Fenotipy glsadkomyshechnykh kletok v sonnykh arteriiakh pri bolezni Takaiasu.

The phenotype of smooth-muscle cells (SMC) of carotid arteries in health and Takayasu's disease were studied using immunofluorescence. In contrast to unaffected carotid artery, medial SMC were represented by heterogenic cell population. Many SMC in this disease expressed fibronectin with ED-A sequence, contained cytokeratin 8 and were deprived of h-caldesmon. Similar phenotypic characteristics are typical for SMC of embryonal phenotype. SMC with this phenotype are observed in the thickened intima of the carotid arteries in Takayasu's disease. It is supposed that SMC precursors in arterial media are activated in this disease, migrate into subendothelial layer and are responsible for the thickening of the intima.

Sialidase activity in normal and atherosclerotic human aortic intima.

Sialidase activity has been determined in homogenates of human aortic intima by measuring the amount of GM1 formed during the incubation of ganglioside GD1a with the tissue homogenates. Areas with atherosclerotic lesions as well as adjacent areas without histological evidence of atherosclerosis were taken for comparison. The rate of GM1 formation from GD1a in the presence of homogenates of the atherosclerotic intima was 20 pmol/h per mg protein. Homogenates of the unaffected intima did not desialylate GD1a. Sialidase activity of the atherosclerotic intima was linear for 1.5 h at GD1a content up to 1.5 nmol and at homogenate protein up to 1 micro g. NH4Cl and NeuAc2en, inhibitors of lysosomal function and plasma membrane-bound sialidase, respectively, reduced sialidase activity of homogenates of the atherosclerotic intima by 94%. The results indicate that atherosclerotic lesions and unaffected intima differ in their activity and specificity of sialidases that cleave gangliosides.

Proliferative activity and expression of cyclin-dependent kinase inhibitor p21WAF1 and p53 protein in endothelial cells of human aorta during replicative aging in vitro.

Experiments with bromodeoxyuridine showed that the count of nonproliferating cells in a monolayer culture of aortic endothelial cells from adult humans rapidly increased during long-term subculturing. Cytochemical assay showed that these cells contain neutral b-galactosidase, the marker of aging cells. Immunocytochemical assay demonstrated that most cells express p53 protein and inhibitor of the cell cycle p21WAF1.

[Expression of T-cadherin in the rat carotid artery wall after balloon injury and in different rat organs]. / Ekspressiia T-kadgerina v razlichnykh organakh, a takzhe v stenke sonnykh arterii pri ballonnom povrezhdenii u krys.

T-cadherin is an unusual glycosilphosphatidylinositol (GPI)-anchored member of the cadherin family of cell adhesion proteins. In contrast to classical cadherins, tissue distribution of T-cadherin so far remained unknown. We examined tissue distribution of T-cadherin in rats using Western blotting and immunohistochemical method. Our results show that T-cadherin is expressed in all types of muscles (cardiac, striated, and smooth muscles), in brain neurons, and spinal cord, in the vessel endothelium, at the apical pole of intestinal villar epithelium, in the basal layer of skin, and eosophagal epithelium. Blood-derived and lymphoid cells as well as connective tissue were T-cadherin-negative. The highest level of T-cadherin expression was revealed in the cardiovascular system. Although T-cadherin was detected in smooth muscle cells, its role in the intimal thickening and restenosis is not known. We examined T-cadherin expression within 1-28 days after balloon injury of rat left carotid arteries. T-cadherin expression was valued immunohistochemically with semiquantitative method. In uninjured arteries, T-cadherin was expressed in endothelial (vWF-positive) cells, and smooth muscle (alpha-actin-positive) cells (SMCs). After denudation of arterial wall, T-cadherin was present both in the media and neointima. We revealed dynamics of T-cadherin expression in the media of injured artery: an essential increase being registered at the stage of cell migration and proliferation in the media and neointima (1-7 days), followed by its decrease to the baseline level (10-28 days). The high upregulation of T-cadherin expression in the media and neointima during migration and proliferation of vascular cells after vessel injury enables us to suggest the involvement of T-cadherin in vessel remodeling after balloon catheter injury.

Effects of transforming growth factor-beta(1)on proliferation of smooth muscle cells in human aortic intima and human promonocytic leukemia THP-1 cells.

We studied the effects of transforming growth factor on proliferation of cultured smooth muscle cells from human aortic intima and proliferation and differentiation of human leukemia THP-1 promonocytes. Transforming growth factor inhibited proliferation of these cells, but stimulated differentiation of THP-1 cells. Therefore, transforming growth factor probably modulates proliferation and differentiation of smooth muscle cells and monocytes/macrophages involved in the pathogenesis of atherosclerotic damages.