Circulating Complex of Lipoprotein(a) and Proprotein Convertase Subtilisin/Kexin Type 9 in the Serum Measured by ELISA.

The presence of a complex of lipoprotein(a) and proprotein convertase subtilisin/kexin type 9 (PCSK9) in the blood of healthy volunteers and patients with cardiovascular diseases was analyzed by ELISA. The levels of the complex varied in a wide range and did not depend on the concentrations of Lp(a) and PCSK9. Moreover, the complex was found not only in patients with cardiovascular diseases, but also in healthy volunteers, which can indicate physiological role of lipoprotein(a) as PCSK9 transporter.

Characteristics of Lipoprotein(a)-Containing Circulating Immune Complexes as Markers of Coronary Heart Disease.

We studied the composition of circulating immune complexes precipitated in the presence of various concentrations of polyethylene glycol in patients with coronary heart disease (CHD) and high concentration of lipoprotein(a) - Lp(a). Precipitation of highly purified Lp(a) preparation with polyethylene glycol was evaluated. The contents of Lp(a), autoantibodies to Lp(a), IgG, and IgM in circulating immune complexes isolated from the sera of donors and CHD patients with normal and high levels of Lp(a) were measured. Circulating immune complexes containing Lp(a) were detected in the plasma of CHD patients with high Lp(a) concentrations. The presence of high concentrations of Lp(a), autoantibodies to Lp(a), and circulating immune complexes in CHD patients suggests that immunological factor contributes to high atherothrombogenicity of Lp(a).

[The effect of increased concentration of lipoprotein (a) on identification of sub-faction of lipoproteins using native electrophoresis technique].

The quantitative analysis of sub-fractions of lipoproteins acquires growing significance in diagnostic and prognosis of cardiovascular diseases. It is well known that presence of lipoprotein (a) in high concentrations significantly distorts results of biochemical analysis, in particular detection of level of cholesterol of low-density lipoproteins. The lipoprotein (a) is a heterogeneous particle and its mobility in the systems used for analysis of sub-fractions of lipoproteins can have significant variability that will bring inaccuracy into results. The data concerning relationship between lipoprotein (a) and sub-fractions of lipoproteins and also their differentiation in various systems of determination of lipid spectrum are quite numerous. The given study is considered as actual one because it analyses input of lipoprotein (a) into results of detection of sub-fractions using the technique with diagnostic significance. The study was carried out for evaluating possible input of lipoprotein (a) into results of quantitative estimation of sub-fractions of lipoproteins by technique of native electrophoresis in polyacrylamide gel used for diagnostic of cardio-vascular diseases. To detect concentration of lipoprotein (a) in blood serum the technique of enzyme-linked immunosorbent assay was applied. The qualitative valuation of content of sub-fractions of lipoproteins was implemented using system Lipoprint Quantimetrix (USA). The sub-fractions of lipoproteins were detected in samples of serum of healthy donor and normolipidic patients before and after removal of lipoprotein (a) using technique of affine chromatography in vitro. It turned out that after removal of lipoprotein (a) analysis of sub-fractions of lipoproteins in plasma of healthy donor detects significant decreasing of level of lipoproteins of medium density. The samples of serum of patients with atherosclerosis besides removal of sub-fractions of lipoproteins of medium density, decreasing of level of large sub-fractions of low density lipoproteins was observed. The analysis of samples obtained after procedures of therapeutic lipoprotein (a) apheresis using columns "Lp (a) Lipopak" (Russia) demonstrated that along with removal of lipoprotein (a), decreasing of concentration of sub-fraction C lipoproteins of medium density in all samples that substantiates in vitro data. In patients without affection and with multi-vessel lesion of coronary bloodstream reliable differences in concentration of lipoproteins of medium density were established. The received data testify that high level of lipoprotein (a) can contribute significant inaccuracies into results of detection of subfractions of lipoproteins. Therefore, application of system Lipoprint (Quantimetrix USA) provides no opportunity to unequivocally interpret data concerning input of sub-fractions of lipoproteins into risk of development of cardio-vascular diseases in patients with pathological lipid profile and higher concentration of lipoprotein (a).

[Effect of cascade plasma filtration on spectrum of subfractions of low density lipoproteins in blood plasma of patients with ischemic heart disease].

We studied effect of cascade plasma filtration on subfractions of low density lipoproteins (LDL) in 16 patients with ischemic heart disease (IHD) and hyperlipidemias refractory to drug therapy. The procedure caused 37.6 ± 1.4%, 43.1 ± 2.5%, and 50.9 ± 1.4% lowering of total, low density lipoprotein cholesterol, and apolipoprotein B-100, respectively. The use of filters led to removal of larger less atherogenic LDL-1 and LDL-2 subfractions with relative accumulation of small dense LDL-3, LDL-4, and LDL-5 subfractions. Lowering of concentrations of all LDL subfractions was caused by specific LDL apheresis by immunosorbtion in 4 patients with IHD. Removal of small dense LDL was more effective than that of large less atherogenic LDL-1 and LDL-2 subfraction. Thus we found differences in spectrum of LDL removed by cascade plasma filtration and immunosorbtion. The use of filters was associated with less effective removal of most atherogenic small dense LDL than of large LDL particles what led to redistribution of concentrations of various LDL subfractions towards atherogenic profile of lipoproteins. These results could constitute a basis for revision of methods of conduct of cascade plasma filtration procedures in patients with IHD.

[Autoantibodies against lipoprotein(a) in patients with coronary heart disease].

OBJECTIVE: Lipoprotein(a) - Lp(a) is an independent risk factor of atherosclerosis and its complications. In spite of the long period of Lp(a) research there is no complete understanding of its physiological role and atherogenic action. The goal of this study was to investigate the presence in human plasma of circulating autoantibodies to Lp(a) belonging to different classes of immunoglobulins, and to elucidate their relationship to the presence and severity of coronary atherosclerosis in middle aged patients with coronary heart disease. MATERIAL AND METHODS: Autoantibodies to Lp(a) and LDL level were measured in 97 men with quantitative angiography data. Among these patients 17 had intact vessels and 80 had stenoses >50% in 1 or more large coronary arteries. RESULTS: Lp(a) level in patients with coronary atherosclerosis (CA) was significantly higher (median 19.0 [95%CI 12.9-27.3] mg/dl) than in patients without CA (median 10.2 [95%CI 4.5-18.3] mg/dl, p=0.05). Level of IgG autoantibodies to Lp(a) was also elevated in patients with verified CA (264 ± 188 and 187 ± 59 RLU, respectively, p=0,003). Correlation analysis showed significant association between Lp(a) concentration and presence of CA (r=0.20, p=0.05). Level of antibodies against Lp(a) correlated with the quantity of affected coronary arteries (r=0.27, p=0.008). CONCLUSION: Plasma concentration of Lp(a) as well as elevated level of autoantibodies to Lp(a) were associated with the presence and severity of coronary atherosclerosis in examined patients.

[DNA aptamer based sorbents for binding human IgE].

DNA aptamer based sorbents are synthesized for binding human IgE. Sorbents effectively removed IgE from human blood plasma. The experimental values of IgE desorption constants were from 11 x 10(-l0) to 1.7 x 10(-10) M depending on the orientation of the aptamer, an insoluble matrix. The sorbents were stable during multiple use. Conditions for sorbent regeneration were picked up. These chromatographic materials can be used for medical and biotechnological applications.

[The immune-enzyme analysis based on chimeric molecule and oligopeptide fragmentations to detect autoantibodies to beta-adrenergic receptor in patients with dilation cardiomyopathy].

The article deals with specification of technique of immune-enzyme analysis to detect autoantibodies to beta-adrenergic receptors (beta1-AP) using compound of oligopeptids representing the fragmentations of extracellular sites beta1-AP and chimeric molecule of extracellular section of receptor This technique significantly exceeds the analogues defined in publications by its sensitivity and correlation with diagnosis.

[Soluble receptors for tumor necrosis factor and lipid metabolism as potential prognostic factors in patients with prostate cancer].

There was investigated the relationship of lipid metabolism, humoral immunity, high sensitivity C-reactive protein and soluble receptors for TNF-alpha with the presence, severity and prognosis of the disease in 85 patients with morphologically verified diagnosis of prostate cancer. Connection with the dynamics of change in PSA as a major predictor of the disease was observed for concentration sRI and sRII to TNF, PSA baseline, total cholesterol and LDL-cholesterol. During follow-up the relative risk of poor prognosis increased by 3 times, and death-in 8.7 times with increasing concentrations of soluble receptors for TNF. The concentration of soluble receptors for TNF may serve as an additional predictor of the presence and clinical course of disease in patients with prostate cancer.

[Affine sorbent with typtophil-threonil-tirosine for binding immunoglobulin G: sorption characteristics and aspects of practical application].

New chromatographic material based on tryptophil-threonil-tirosine was prepared. This sorbent effectively binds human, sheep, goat and cow immunoglobulins G. New sorbent shows high selectivity for removing immunoglobulins from blood plasma. Effective sorption capacity is 15-25 mg of immunoglobulin G per ml of matrix. Optimal method of covalent attachment ligand to polysaccharide matrix allows achieving high stability of the sorbents in terms of use and storage. This sorbent can be used in medicine and biotechnology.

[High level of lipoprotein (a) as a predictor of poor long-term prognosis after coronary artery bypass surgery].

Study aim was to investigate the association of lipoprotein (a) [Lp(a)] level with the development of cardiovascular complications in long-term follow-up period after coronary artery bypass grafting (CABG). Patients with chronic ischemic heart disease (IHD) (n = 361, 88% men, mean age 55 +/- 9 years) who had had CABG were included in the study. Before surgery we assessed presence of classical risk factors, left ventricular ejection fraction, concentrations of lipids and Lp(a) in blood serum. During follow-up (from 1 to 140, mean 66 +/- 34 months) we registered cardiac deaths, nonfatal myocardial infarctions (MI), strokes, repeat procedures of revascularization, and hospitalizations due to relapse or progression of angina pectoris. Information on prognosis was obtained from 263 patients. In 109 of them we registered 142 serious events including cardiac death n = 20 (14%), nonfatal MI n = 14 (10%), myocardial revascularization (n = 35), 29 (20%) with stenting), repeat CABG n = 6 (4%), hospitalization due to angina pectoris n = 53 (37%), stroke n = 4 (3%), noncardiac outcome n = 16 (10%). In subjects with hyperlipidemia (a) [HLp(a) - Lp(a) > 30 mg/l] survival after CABG was lower (log rank p < 0.001): 11 of 93 (11.3%) and 9 of 170 (5.2%) patients died among those with Lp(a) > 30 and < 30 mg/I, respectively. Relative risk (RR) of any cardiovascular complication was 3.24 (95% confidence interval [CI] 2.18 to 4.83, p < 0.001), of death - 2.89 (95% CI 1.31 to 6.35, p < 0.01), and of MI A 1.01 (95% CI 1.00 to 1.02; p = 0.02). RR of development of MI and cardiac death in patients with HLp(a) in 5 years was 2.61 (95% CI 1.11 to 5.74; p = 0.02), in 10 years - 2.95 (95% CI 1.50 to 5.79; p < 0.001). In patients with chronic IHD high level of Lp(a) can serve as independent predictor of unfavorable events including death and nonfatal MI during 10 years after CABG.

[Pleiotropic effects of nicotinic acid therapy in men with coronary heart disease and elevated lipoprotein(a) levels].

PURPOSE: To assess effects of niacin on risk factors of atherosclerosis in men with coronary heart disease (CHD) and high lipoprotein(a) [Lp(a)] levels. MATERIAL AND METHODS: Sixty men (mean age 54+/-6 years) with angiographic evidence of CHD were randomized into two groups. Active group (n=30) received extended release nicotinic acid 1500 mg, control group consisted of remaining 30 patients. All patients received basic therapy with atorvastatin 10-40 mg qd. Blood samples were collected for total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), Lp(a), lipoprotein-associated phospholipase A2 (Lp-PL-2), high-sensitivity C-reactive protein (hsCRP), complex of tissue-type plasminogen activator with plasminogen activator inhibitor type 1 (tPA/PAI-1). Carotid intima media thickness (CIMT) was measured at baseline and after 6-months therapy. RESULTS: There was no statistically significant difference between the groups in the clinical and biochemical characteristics. During the study lipid profile data were within the target levels. In the active group median percent decrease of Lp(a) level was 23% (from 84+/-40 to 67+/-25 mg/dl after 6 weeks and up to 65+/-37 mg/dl after 6 months of treatment, p<0.01); LDL-C, TG, tPA/PAI-1, and Lp-PL-2 mass levels decreased by 25, 20, 25, and 32%, respectively; HDL-C increased by 16% (p<0.05 vs baseline, respectively). Nicotinic acid treatment produced statistically significant reduction nicotinic acid of the mean CIMT (right: 0.83+/-0.16 vs 0.77+/-0.17 mm, p<0.05; left: 0.88+/-0.21 vs 0.82+/-0.17, p<0.05). In control group no changes of CIMT or blood tests were observed. CONCLUSION: In men with CHD and Lp(a) excess of addition to atorvastatin results in regression of CIMT on an average of 0.06 mm in 6 months. Such rapid and significant effect on the arterial wall structure can be attributed to the complex influence of nicotinic acid on Lp(a), lipids, Lp-PL-2 and thrombogenic factors. This is the first study providing the evidence of using Lp(a) as one of therapeutic targets in patients with high Lp(a) levels for achieving beneficial effect on a surrogate marker of atherosclerosis.

[Preparation of affinity sorbents with immobilized synthetic ligands for therapeutic apheresis].

Preparation and stability of a few examples of medical sorbents are described. A simple and practical technique has been developed for sorbent preparation with the low weight synthetic ligands such as amino acids, peptides or oligosaccharides. This approach to sorbent preparation enables the development of the new affine columns generation for medicine and biotechnology to be carried out with ease.

[Synthesis and properties of a new conformational antigen modeling an extracellular region of beta(1)-adrenoreceptor].

Two fragments corresponding to the 125-133 and 206-218 sequences of a molecule of the beta(1) adrenoreceptor (autoantibodies to this protein are often found in patients with dilated cardiomyopathy) were synthesized by the solid phase method with the use of Fmoc technology. Two new conformational antigens were prepared by directed (regioselective) and undirected (spontaneous) formation of intramolecular and intermolecular disulfide bridges between the corresponding cysteine residues of the synthesized peptides. One of these antigens consisted of a mixture of disulfide isomers, and another antigen was an isomer with a natural arrangement of S-S bridges. Immunosorbents were obtained by immobilization of the synthesizes antigens on the bromocyanogenactivated sepharose and applied to the removal of autoantibodies in a beta(1)-adrenoreceptor from the blood plasma of patients. We demonstrated that the sorbents on the basis of the conformational antigens were more effective in comparison with those containing linear peptide precursors.

[The role of atherosclerosis risk factors in development of ischemic heart disease in young men].

AIM: To determine distribution of different atherosclerosis risk factors and their correlation with severity of coronary arteries (CA) affection in young men. MATERIAL AND METHODS: A total of 235 males aged 28-45 years were examined with coronarography which detected more than 50% narrowing in one or several major CA in 200 patients (the study group with coronary artery disease), 35 males without coronary stenosis served control. Atherosclerosis risk factors, serum lipids, lipoprotein(a), fibrinogen, C-reactive protein (CRP) were assessed. RESULTS: Smoking and hyperlipidemia (HLE) were registered in the study group more frequently. The level of lipoprotein(a) above 30 mg/dl was recorded in 98 (49%) and 7 (20%) patients of the study and control group, respectively (p = 0.001). As shown by a correlation analysis, the number of affected CA was associated with smoking (r = 0.2; p < 0.001), HLE (r = 0.23; p < 0.001), concentration of total cholesterol (r = 0.23; p < 0.0.001), lipoprotein (a) (r = 0.26; p < 0.001) and CRP (r = 0.26; p < 0.05). The level of lipoprotein(a) in patients with myocardial infarction and occluded artery was significantly higher than in patients without myocardial infarction and non-occlusive CA affection. CONCLUSION: The presence and severity of coronary atherosclerosis in young men with coronary artery disease are associated with smoking, HLE and high concentration of lipoprotein (a).

Comparative analysis of efficiency and specificity of various sorbents for apheresis of low-density lipoproteins.

Efficiency of sorbents for LDL apheresis was compared in vitro. The sorbents based on ion-exchange interaction of the ligand with LDL (Liposorber, DALI) exhibited minimum specificity towards the eliminated component, while immunosorbents (LNP-Lipopak, LDR-TheraSorb) were most efficient. By sorption capacity, the available hemosorbents are inferior to plasmasorbents, which explains low efficiency of the therapy based on single application of hemosorbents especially in patients with consederably increased content of LDL cholesterol.

[Apolipoprotein B100 as a risk factor of acute coronary syndrome and this risk factor effect on arterial hypertension in patients with ischemic heart disease].

AIM: To clarify correlations between an elevated concentration of apolipoprotein B100 (apoB) in blood plasma and risk of acute coronary syndrome (ACS); to study apoB level in hypertensive patients and its correlation with ischemic heart disease (IHD) risk in these patients. MATERIAL AND METHODS: Lipid serum spectrum (cholesterol, triglycerides (TG), lipoprotein a (Lpa) and apoB was studied in 456 patients with ACS by NYHA criteria, 119 patients with chronic IHD and 86 patients free of cardiovascular diseases (controls). All 575 patients with IHD were divided into those with and without hypertension (426 and 149 patients, respectively). RESULTS: Lpa was significantly higher in patients with ACS; apoB was higher in ACS and chronic IHD patients. ApoB was higher in IHD normotensive patients than in controls and higher in IHD hypertensive patients than in IHD normotensive patients and in the control group. Lpa in IHD hypertensive patients was significantly higher (p < 0.045) than in the controls as well as TG (p < 0.05). By the other parameters the groups did not differ. CONCLUSION: The blood plasma level of apoB higher than 130 mg/dl is an independent and significant risk factor of ACS in IHD patients especially at the age under 60. The level of apoB over 115 mg/dl is a significant risk factor of IHD. The significance of this lipid factor rises in concomitant hypertension.

[Ethnic differences in apolipoprotein B levels in hyperlipidemia in Russian and Kirghiz populations]. / Etnicheskie osobennosti v urovne apolipoproteina B pri giperlipidemiiakh u russkikh i kirgizov.

AIM: To evaluate the levels of apolipoprotein B (apo-B) and coronary heart disease (CHD) risk factors in Russians and the Kirghiz with primary hyperlipidemia (PHL). MATERIAL AND METHODS: Lipid spectrum of the blood (LDLP and HDLP cholesterol, total cholesterol, triglycerides), apo-B, CHD risk factors were studied in 60 Russian and 75 Kirghis patients with PHL aged 28 to 67 years (mean age 50.0 +/- 7.59 years, 56 females and 79 males). RESULTS: In Russians a mean level of LDLP cholesterol and apo-B was significantly higher than in Kirghiz patients (3.95 +/- 1.29 mmol/l vs 3.51 +/- 1.17 mmol/l, p = 0.042; 173.3 +/- 57.3 mg/dl vs 145.5 +/- 49.3 mg/dl, p = 0.003, respectively). CHD in both ethnic groups occurred with similar rates. The multifactorial regression analysis shows that an apo-B concentration can serve an independent risk factor associated with CHD in the Kirghiz population (beta = 0.25, p = 0.03) while in Russians living in Kirghizia this factor is a low content of HDLP cholesterol (beta = -0.25, p = 0.05).

[Effect of hormone replacement therapy on blood serum lipids in postmenopausal women with type 2 diabetes]. / Dinamika pokazatelei lipidnogo obmena pod vliianiem zamestitel'noi gormonal'noi terapii u zhenshchin v postmenopauze s sakharnym diabetom 2-go tipa.

There are limited data concerning influence of hormone replacement therapy (HRT) on lipid profile in women with type 2 diabetes. Aim of the study was to compare changes of blood lipids during HRT in postmenopausal women with and without type 2 diabetes. Seventy seven women included in the study were assigned to 1 of 4 groups, basing on being diabetic or nondiabetic, and further subdivided into users of estrogen alone (ERT), and of estrogen plus progestin (EPRT). Effect of 6-month ERT (oral estradiol valerate 2 mg/day) and EPRT (oral estradiol valerate 2 mg/day sequentially combined with cyproterone acetate 1 mg/day) on total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides and lipoprotein (a) [Lp(a)] was separately assessed. EPRT and ERT caused decrease in LDL-C by 15% and 12%, and increase in HDL-C by 12% and 13%, respectively, in patients with diabetes (p<0.05 in all cases). LDL-C decreased by 11% and 15%, respectively, in women without diabetes (p<0.05 in all cases). Lp(a) was also reduced 25% with EPRT (p<0.01) and ERT (p<0.05). HDL-C increased 10% (p<0.05) with ERT but remained unchanged with EPRT. In conclusion, changes in all lipid parameters except Lp(a) caused by ERT and EPRT were comparable in postmenopausal women with and without type 2 diabetes.

[Apheresis of immunoglobulins - new approach to the treatment of severe dilated cardiomyopathy]. / Aferez immunoglobulinov - novyi podkhod k lecheniiu tiazhelykh form dilatatsionnoi kardiomiopatii.

Two courses of immunoadsorption with 'Ig Adsopak' were used in the treatment of a patient with dilated cardiomyopathy (DCM) during which all class G and partially class M and A immunoglobulins were removed. Every course consisted of 5 daily procedures and resulted in removal of 98% of immunoglobulins. This was associated with complete removal of autoantibodies to beta1-adrenoreceptor. After the end of a course loss of immunoglobulins was replenished by intravenous infusion of Pentaglobin and Oktagam. Echocardiographic study carried out before, during and after second course of apheresis revealed reduction of left and right ventricular and atrial volumes and dimensions, improvement of contractility of anterior part of interventricular septum and of anterolateral left ventricular wall. As efficacy of drug therapy of dilated cardiomyopathy is low and facilities of cardiac transplantation are limited the method of therapeutic apheresis reveals novel perspectives of the treatment of dilated cardiomyopathies.

[Lipoprotein (a) and ischemic heart disease in patients with hypertensive disease]. / Lipoproteid(a) i ishemicheskaia bolezn' serdtsa u bol'nykh gipertonicheskoi bolezn'iu.

Relationship between level of lipoprotein (a) and presence of ischemic heart disease (IHD) was studied in 191 patients with hypertensive disease (essential hypertension) (112 men, 79 women, age 56.9-/+10.6 years) and 33 patients with normal blood pressure (23 men, 10 women, age 50.8-/+11.0 years). Concentration of lipoprotein (a) in men with hypertension and IHD (n=62) was significantly higher than in men with hypertension without IHD (n=50) (median 19 and 9 mg/dl, respectively, p=0.02). Women with hypertension and with (n=23) and without (n=56) IHD had similar blood levels of lipoprotein (a) (median 13 and 15 mg/dl, respectively, p=0.89). Difference in lipoprotein (a) levels between patients with hypertensive disease and those with normal blood pressure was not significant (median 14 and 10 mg/dl, respectively, p=0.50).