Pluronics suppress association of low-density lipoproteins inducing atherogenesis.

We studied the effect of pluronics P85, L61, and F68 with different hydrophilic-lipophilic characteristics on association of LDL. It was found that pluronics with pronounced hydrophobic properties (P85 and L61) in concentrations close to or surpassing the critical concentration of micelle formation inhibited LDL association, while hydrophilic pluronic F68 in all concentrations had no effect on LDL association.

[The role of oxidative processes in augmentation of atherogenity of low density lipoprotein particles].

We investigated action of natural dicarbonyl compounds which are formed in atherosclerosis and diabetes on properties of low density lipoproteins (LDL) such as surface charge, conformational changes of apoB100, susceptibility to oxidation. and aggregation rate. It was found that malonic dialdehyde (MDA) compared with glyoxal and methylglyoxal is more effective modificating agent of protein part of LDL particle. Nevertheless glyoxal and methylglyoxal-dependent modification of LDL can accelerate processes of further free radical peroxidation increasing atherogenity of LDL particles.

[Neuroimmunoendocrine mechanisms of protective effects of medical rehabilitation in elderly patients].

Physical rehabilitation is the basic method for all programs of medical rehabilitation on different pathologies. Such important diseases as chronic heart failure, diabetes mellitus, chronic pulmonary obstructive disease have the high risk of disability. There is a high motivation to their rehabilitation. These diseases progress in situations associated with immune inflammation. Such signal molecules as tumor necrosis factor (TNF-alpha), interleukins-1,6 (IL-1,6) take part in these processes. The role of medical rehabilitation methods in connection of neuroimmunoendocrinic homeosthasis are described in this article.

[The role of the short-wave therapy in rehabilitation of elderly patents with chronic obstructive pulmonary disease].

The positive clinical effects of using the short-wave therapy in rehabilitation of patients with chronic obstructive pulmonary disease are presented in this article. 49 patients were included in this investigation. The criteria of successful rehabilitation were more expressive in the cases when the short-wave therapy was included in rehabilitative program.

[Clinical aspects of the using of clopheline in postoperative period in elderly patient with arterial hypertension].

The positive clinical effects of using of clopheline in postoperative period in elderly patent with arterial hypertension are presented in this article. Clopheline has the good hypotensive effects. This drug may be recommended for treatment the hypertensive postoperative reaction.

Deglycosylation of apo B-containing lipoproteins increase their ability to aggregate and to promote intracellular cholesterol accumulation in vitro.

Sub-fractions of all apo B-100 containing lipoproteins (low density lipoproteins, very low density lipoproteins and intermediate density lipoproteins) with reduced contents of sialic acid were found in vivo in human blood. These lipoproteins were inclined to spontaneously form aggregates and were able to stimulate accumulation of cholesterol in cells cultured from human aortic intima. In vitro treatment of apo B-containing lipoproteins with 2,6- and 2,3-specific sialidases, alpha-mannosidase, endoglycosidases F1 or F2 or peptide-N-glycanase F also stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in cells of the intact human aortic intima. So, deglycosylation of various apo B-containing lipoproteins possibly occurs in the blood, decreases their resistance to aggregation and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, thereby increasing their atherogenic potential.

[LDL oxidation and uptake by monocyte-derived macrophages from blood of patients with ischemic heart disease].

The aim of this study was to test our hypothesis that monocyte-derived macrophages of patients with ischemic heart diseases (IHD, MPIHD) were prestimulated (primed) or stimulated cells whose capacity for LDL oxidation and uptake exceeded that ofmacrophages from healthy donors (MPN). Monocytes were obtained from the blood of 18 healthy donors and 25 IHD patients; plasma LDL--from 16 another group healthy donors (LDLN) and 15 patients with family hypercholesterolemia. Incubation of LDLN or LDLH with MPIHD or MPN was carried out under aerobic and hypoxic conditions. It was shown that incubation of LDLN or LDLH with MPIHD TBARS accumulation, LDL aggregation, apoB fragmentation were observed earlier and proceeded more actively than in the case of incubation with MPN. MPIHD (compared to MPN) more actively uptook LDLH and LDLN as accumulated greater amounts of total cholesterol (TCh) (by a factor of 1.8-2.1; p < 0.05-0.01), and their viability decreased to a markedly greater degree (p < 0.01). MPIHD and MPN also oxidized and took up LDLH with a higher intensity than LDLN, and their capacity for LDL oxidation and uptake increased, under hypoxic condition, compared to those under aerobic conditions. Thus, new experimental results provide direct evidence that macrophages of IHD patients are in vivo priming or stimulated cells and that this stimulation, especially in combination with hypercholesterolemic LDL and hypoxia, is a very strong risk factor that can predispose these patients to the onset or progression of atherosclerosis. Using MPIHD, it was created express-method for evaluation the degree of monocyte/macrophage stimulation in patients with IHD, selection of premedication medicine and new antiatherosclerotic and antiischemic drugs.

Oxidation-induced aggregation of LDL increases their uptake by smooth muscle cells from human aorta.

Oxidative modification of human blood LDL induced by Cu2+, NaOCl, or 2,2-azobis-(2-aminopropane hydrochloride) was followed by their partial aggregation. Separation of oxidized LDL into aggregates and nonaggregated particles showed that they are characterized by a similar degree of oxidative modification. In contrast to nonaggregated particles, LDL aggregates in the same concentration significantly increased cholesterol content in smooth muscle cells from the intact (no involoved in atherosclerosis) human aortic intima. Our results indicate that atherogenicity of LDL oxidized by various factors is mainly associated with the formation of aggregates, but does not depend on the degree of oxidative modification.

Effect of plant extracts on trans-sialidase activity in human blood plasma.

We studied the effects of plant extracts and products of their biological treatment on trans-sialidase activity in human blood plasma. Extracts of kelp, fucus, yarrow, Saint John's wort, onion, and honey in vitro decreased trans-sialidase activity. Extracts of pollen (beebread) and garlic powder produced the maximum inhibitory effect. trans-Sialidase activity of blood plasma ex vivo decreased 2-fold after peroral administration of pollen and garlic powder. A correlation was found between the decrease in trans-sialidase activity in blood plasma and ability of blood plasma to induce cholesterol accumulation in cultured cells from the intact human aortic intima.

Desialylation decreases the resistance of apo B-containing lipoproteins to aggregation and increases their atherogenic potential.

Subfractions of apo B-containing lipoproteins (VLDL and intermediate-density lipoproteins) with reduced content of sialic acid were found in human blood. These lipoproteins are characterized by high capacity to spontaneous association (aggregation) and stimulated accumulation of cholesterol in smooth muscle cells of human aortic intima. In vitro treatment of apo B-containing lipoproteins with alpha-2,6-sialidase and alpha-2,3-sialidase stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in smooth muscle cells of the intact human aortic intima. Probably, desialylation of various apo B-containing lipoproteins can occur in the blood; this process decreases their resistance to aggregation, and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, i.e. increases their atherogenic potential.

Proteolysis of apoprotein B-100 impairs its topography on LDL surface and reduces LDL association resistance.

Serine proteinases (trypsin and chymotrypsin) cause destruction of apolipoprotein B-100 on the surface of human blood LDL. Incubation of LDL with these enzymes increases the mean size of LDL particles. Proteolysis of apolipoprotein B-100 induces changes in surface structure, destabilizes LDL particles, and reduces their association resistance. Presumably, this proteolytic modification of LDL with subsequent association of these particles plays an important role in accumulation of cholesterol in the vascular wall and in the development of early stages of atherosclerosis.

Phospholipid hydrolysis with phospholipases A2 and C impairs apolipoprotein B-100 conformation on the surface of low density lipoproteins by reducing their association resistance.

Modification of apolipoprotein B-100 conformation on the surface of LDL isolated from human blood was demonstrated by enzyme immunoassay with a panel of monoclonal antibodies to this protein. The study by the light transmission fluctuation method showed that incubation of LDL with phospholipases A2 or C led to association of LDL particles. This lipolytic modification seems to impair LDL surface properties inducing association of these particles, which can play an important role in lipid accumulation in the vascular wall and at early stages promote the development of atherosclerosis.