Proteomic biomarker evaluation using antibody microarrays: association between analytical methods such as microarray and ELISA

OBJECTIVE

To evaluate the associations between analytical methods, such as microarray and enzyme-linked immunosorbent assay (ELISA); expedient cutoffs; and the lowest possible number of microarrays in analysis for target biomarker estimation in case-control studies.

METHODS

This study included 321 serum specimens, gathered in different case-control studies to test for atherosclerosis and atrial fibrillation. Among them, 48 serum specimens were analyzed using microarray technology. We used ELISA and commercial kits for confirmation of the results.

RESULTS

Three proteins-cadherin-P, neuronal nitric oxide synthase, and adenovirus fiber-were shown to have distinctly different values in the case group vs the control group. As a result, we used those proteins as the target for confirmation using our alternative analytical method. Also, these protein values represented the limiting range between the highest and lowest differences in case-control groups. The results of microarray assay were confirmed using ELISA and commercial kits in the same specimens, in which microarray profiling was performed, and also in separate large case-control groups.

CONCLUSIONS

A 1.5-fold difference in the protein content, as measured using microarray technology, was shown to be sufficient for further investigation of the candidate proteins. As few as 3 microarrays were considered sufficient for perspective evaluation of the target proteins. Microarray serum profiling, therefore, provides semiquantitative determination of protein in serum.

Associations of adenovirus-reactive immunoglobulins with atrial fibrillation and body mass index

Adenovirus (AdV) has been suggested to be involved in pathogenesis of atrial fibrillation (AF). We aimed to evaluate an association between AdV-specific immunoglobulins G in the serum (AdV-IgG) and AF. The present case-control study comprised two cohorts, including cohort 1 of patients with AF and cohort 2 of asymptomatic subjects. Initially, two groups, MA and MB, were selected from the cohorts 1 and 2, respectively, for serum proteome profiling using an antibody microarray to identify possible relevant protein targets. The data of microarray analysis indicated a possible overall increase in the total adenovirus signals in the group MA vs. group MB, suggesting potential relevance of adenoviral infection to AF. Then, the groups A (with AF) and B (control) were selected from the cohorts 1 and 2, respectively, to assay the presence and levels of AdV-IgG- by ELSA. The prevalence of AdV-IgG-positive status demonstrated a 2-fold increase in the group A (AF) compared with that in the group B (asymptomatic subjects); odds ratio 2.06 (95%CI: 1.11-3.84; P = 0.02). The prevalence of obesity demonstrated an approximately 3-fold increase in AdV-IgG-positive patients of the group A compared with that in AdV-IgG-negative patients of the same group A (odds ratio 2.7; 95% CI: 1.02-7.1; P = 0.04). Thus, AdV-IgG-positive reactivity was independently associated with AF, and AF was independently associated with BMI, indicating that adenoviral infection may be a possible etiological factor for AF.

Application of an antibody microarray for serum protein profiling of coronary artery stenosis

Protein expression profiling in the serum is used to identify novel biomarkers and investigate the signaling pathways in various diseases. The aim of the present study was to evaluate serum biomarkers associated with coronary artery stenosis resulting from atherosclerosis. The study included 4 groups of subjects: group A and B with and without coronary lesions, respectively, were selected from a previously reported cohort study on coronary atherosclerosis, control group C comprised of asymptomatic subjects and group D was used for independent validation of the microarray data by ELISA. Labeled serum proteins were profiled by an Explorer antibody array, which included 656 specific antibodies in two replicates (FullMoon Biosystems, USA). Cadherin-P, interleukin-5, glutathione S-transferase Mu, and neuronal nitric oxide synthase were sex-independently increased in Group A compared with those in group B. The microarray data on cadherin-P were externally validated in an independent group D using ELISA. Fibroblast growth factor-1, FGF-2, collagen II, granulocyte-macrophage colony-stimulating factor, IL-1 alpha, angiopoietin-2, granulocyte colony-stimulating factor, lymphocyte cell-specific protein tyrosine kinase, and IkappaB kinase b were increase in men in group A compared with group B. Cyclin-dependent kinase 1, DNA fragmentation factor subunit alpha DFF45/ICAD, adenovirus type 2 E1A, calponin, ADP-ribosylation factor-6, muscle-specific actin, thyroid hormone receptor alpha, and alpha-methylacyl-CoA racemase were specifically increased in women in Group A compared with group B. Alterations in the levels of specific proteins may point to the signaling pathways contributing to coronary atherosclerosis, and these proteins will be useful biomarkers for the progression of cardiovascular diseases.

A Novel Integrated Biomarker for Evaluation of Risk and Severity of Coronary Atherosclerosis, and Its Validation

Objective: To assess the feasibility of a combination of biochemical and imaging parameters for estimation of risk and severity of coronary atherosclerosis (CA), and to verify the created integrated biomarker (i-BIO) on independent cohort. Methods: Two cohorts of patients admitted to the hospital for coronary angiography and ultrasound carotid dopplerography were enrolled into the study (n = 205 and n = 216, respectively). The extent of CA was assessed by Gensini Score (GS). Results: According to GS, participants were distributed as follows: atherosclerosis-free (GS = 0), CA of any stage (GS > 0), subclinical CA (GS < 35), severe CA (GS ≥ 35). Based on the analysis of mathematical models, including biochemical and imaging parameters, we selected and combined the most significant variables as i-BIO. The ability of i-BIO to detect the presence and severity of CA was estimated using ROC-analysis with cut-off points determination. Risk of any CA (GS > 0) at i-BIO > 4 was 7.3 times higher than in those with i-BIO ≤ 4; risk of severe CA (GS ≥ 35) at i-BIO ≥ 9 was 3.1 times higher than at i-BIO < 9. Results on the tested cohort confirmed these findings. Conclusions: The i-BIO > 4 detected CA (GS > 0) with sensitivity of 87.9%, i-BIO ≥ 9 excluded patients without severe CA (GS < 35), specificity 79.8%. Validation of i-BIO confirmed the feasibility of i-BIO > 4 to separate patients with any CA with sensitivity 76.2%, and of i-BIO ≥ 9 to exclude atherosclerosis-free subjects with specificity of 84.0%.

Lipoprotein Profile in Populations from Regions of the Russian Federation: ESSE-RF Study

This study aimed to describe the dyslipidemia prevalence and pattern among adult populations from different regions (n = 13) of the Russian Federation (RF). Randomly selected samples (n = 22,258, aged 25-64) were studied according to the ESSE-RF protocol. Lipoprotein parameters were estimated by routine methods. Statistical analyses were performed using R software (v.3.5.1). The overall dyslipidemia prevalence was 76.1% (76.9/75.3% for men/women). In women, total cholesterol (TC) and low-density lipoprotein (LDL)-C levels gradually increased with age (from 4.72 to 5.93 and from 2.76 to 3.79 mmol/L, respectively); in men, they reached a maximum by 45-54 (5.55 and 3.55 mmol/L, respectively) and then decreased. No differences in high-density lipoprotein (HDL)-C in men of different ages were found, but slight decreases in HDL-C and apo AI were observed in women by 55-64 years. No pronounced associations between education and lipid levels in men were observed; higher-educated women showed significantly better lipoprotein profiles. Similar associations between lipids and income level were detected. Women from rural areas had higher TC and triglycerides than urban residents. Regardless of sex, rural residents had higher HDL-C and apo AI, and reduced apo B/apo AI. Conclusion: Information on the peculiarities of dyslipidemia prevalence and lipoprotein profile depending on sex, age, residential place, and socioeconomic status is useful for assessing the global ASCVD risk, and for risk modeling based on national data.

Subfractional Spectrum of Serum Lipoproteins and Gut Microbiota Composition in Healthy Individuals

Aim: To reveal the relationship between gut microbiota composition and subfractional spectrum of serum lipoproteins and metabolic markers in healthy individuals from Moscow. Methods: The study included 304 participants (104 were men), who underwent thorough preclinical assessment to exclude any chronic disease as well as cardiovascular pathology. Lipoprotein subfractional distribution was analyzed by Lipoprint LDL System (Quantimetrix, Redodno Beach, CA, USA). Gut microbiota composition was assessed by 16S rRNA sequencing of V3-V4 regions. Results: High gut microbiota diversity was positively associated with HDL-cholesterol (C) level and negatively associated with abdominal obesity, BMI, and dyslipidemia. According to selbal analysis, excessive representation of Prevotella spp. was positively associated with IDL-C and LDL-2-C. VLDL-C correlated with Ruminococcus_u/Faecalibacterium_prausnitzii balance. An unexpected positive relationship between LDL-C level and Bifidobacteriaceae_u/Christensenellaceae_u to Bifidobacterium_u balance was found, which may reflect the importance of the integrative microbiota assessment. Low microbiota diversity was associated with obesity, abdominal obesity and low HDL-C level. Conclusions: Gut microbiota imbalance may be one of the components involved in metabolic disorders. The balance of microorganisms and the microbiota diversity may play a more significant role in human health than individual bacterial genera.

Visual Scale as a Non-Invasive Method for Evaluation of Risk and Severity of Coronary Atherosclerosis

Aim      To evaluate quantitative and qualitative characteristics of atherosclerotic plaques (ASP) in carotid arteries (CA) and femoral arteries (FA) and to use these data for developing a visual scale (VS) for noninvasive diagnosis and determination of severity of coronary atherosclerosis.Material and methods  This study included 216 patients (115 men and 101 women) aged 24 to 87 years (mean age, 61.5±10.73 years). All patients underwent coronary angiography (CAG) for detecting and determining severity of CA atherosclerosis and duplex scanning (DS) for detecting atherosclerosis of CA and FA.Results Analysis of ultrasound parameters of ASP in CA and FA showed that the maximal ASP height, moderate stenosis and maximal stenosis of the arterial bed had higher predictive values than other ultrasound parameters. These parameters were used for forming diagnostic complexes, on the basis of which two individual VSs for CA and FA were developed. Based on the high prognostic value of both scales, they were combined into one that was named VSCOMB. A ROC analysis determined cut-off points of the VSCOMB for diagnosis of CA atherosclerosis of various severity. VSCOMB scores  &gt;4 indicated pronounced CA atherosclerosis with sensitivity of 86.1 % and specificity of 87.5 % whereas VSCOMB scores  ≤4 excluded it. Thus, VSCOMB score 0-1 indicated the absence of CA atherosclerosis; score 2-4 indicated the presence of subclinical CA atherosclerosis; and score &gt;4 indicated severe CA atherosclerosis.Conclusion      A VSCOMB was developed that includes a set of ultrasound parameters for CA and FA and is useful for noninvasive diagnosis of CA atherosclerosis of various severity. Simple and convenient use of VSCOMB allows it to be used at the screening stage to detect subclinical CA atherosclerosis and to prevent its progression.

Lipoprotein(a) in an adult sample from the Russian population: distribution and association with atherosclerotic cardiovascular diseases

INTRODUCTION

Lipoprotein(a) (Lp(a)) is recognized as an independent risk factor for atherosclerotic cardiovascular disease (ASCVD). The aim of this study was to estimate the distribution of Lp(a) levels in working age adults from the Russian population and to assess its association with ischemic heart disease (IHD), myocardial infarction (MI), stroke, diabetes mellitus (DM), and arterial hypertension (AH).

MATERIAL AND METHODS

This substudy of the population-based study "Epidemiology of Cardiovascular Diseases and their Risk Factors in Some Regions of the Russian Federation" (ESSE-RF) included 8461 subjects aged 25-64 years (63.7% women) without lipid-lowering drugs. Atherosclerotic cardiovascular disease was self-reported. Lp(a), apolipoproteins AI and B, and lipid and glucose levels in blood serum were determined.

RESULTS

The prevalence of Lp(a) ≥ 30 mg/dl was 20.5% and 23.0%, and prevalence of Lp(a) ≥ 50 mg/dl was 13.3% and 15.2%, in men and women, respectively. An association of Lp(a) with IHD, MI, and AH, but not with stroke and DM, was shown. A cut-off level of Lp(a) of 9 mg/dl was determined, above which there was increased frequency of MI (by 59.2%, p = 0.02), IHD (by 33.4%, p < 0.001), and AH (by 11.6%, p < 0.001). In the multivariate analysis only the association of Lp(a) with IHD (1.19 (1.01-1.41), p = 0.038) and MI (1.57 (1.06-2.38), p = 0.028) remained significant.

CONCLUSIONS

Lipoprotein(a) level ≥ 30 mg/dl was detected in every fifth adult aged 25-64 years. Increased risk of MI and IHD starts at an Lp(a) serum level above 9 mg/dl.

ISO 20387 biobanking standard. Analysis of requirements and experience of implementation

Currently one of the most important problems facing biobanking specialists is the standardization of biobanks operation. Close attention is paid to this issue by international biobanking organizations, such as ISBER and BBMRI-ERIC, which develop regulatory documentation in this area. The article provides examples of standardization tools - implementation of the ISO 9001 quality standard and ISBER Best Practices. General information about the development, scope, and structure of the ISO 20387 standard is provided. The standard does not provide ready-made solutions and does not contain specific requirements for storage temperature or biosamples processing in biobanks, allowing each biobank to adapt its own management system to existing conditions and needs. The standard contains requirements for both the organization of the biobanking and the supporting processes - personnel competence; requirements for biological safety; infrastructure management, including equipment used by the biobank, environmental parameters that affect the storage of biomaterial. The standard contains requirements for the quality management system of biobank, as a necessary element of the organization of any biorepository. At the initiative of the Russian National Association of biobanks and biobanking specialists (NASBIO), development of the Russian standard GOST R ISO 20387 «Biotechnology. Collection and storage of biological samples in biobanks. General requirements» is included in the plan of the National Standardization Program for 2020 by order of Rosstandart No. 2612 of 11/01/2019. Implementing quality standards is a long and painstaking process that requires the involvement of all employees and certain resources. However, the effectiveness of strict compliance exceeds the cost of developing, implementing and maintaining management systems, as it significantly increases the confidence of researchers in the work of biobanks, guarantees high quality of biospecimens and associated data, and creates opportunities for cooperation, both at the national and international level, based on the application of common quality standards in the work.

[Prediction of Subclinical Coronary Atherosclerosis in Patients with High and Very High Cardiovascular Risk]

Objective To develop a diagnostic rule for detection of patients (pts) with high probability of subclinical atherosclerosis among those with high or very high cardiovascular (CV) risk.Materials and Methods This cross-sectional study enrolled 52 pts (32 men [62 %]), aged 40 to 65 years [mean age 54.6±8.0]) with high or very high CV risk (5-9 and ≥10 % by The Systematic Coronary Risk Estimation Scale [SCORE], respectively). All participants underwent cardiac computed tomography (CT) angiography and calcium scoring. Traditional risk factors (RFs) (family history of premature CVD, smoking, overweight / obesity and abdominal obesity, hypertension, type 2 diabetes mellitus, lipids parameters (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides) and lipids-related markers (apolipoprotein A1, apolipoprotein B, ApoB / ApoA1 ratio), biomarkers of inflammation (high-sensitivity C-reactive protein [hs CRP], fibrinogen), indicator carbohydrate metabolism (glucose), ankle-brachial index, stress-test, carotid plaques according to ultrasound were evaluated in all pts. Psychological RFs were evaluated using Hospital Anxiety and Depression Scale and DS-14 for type D personality.Results All pts were divided into 2 groups according to the CT angiography results: pts in the main group (n=21) had any non-obstructive lesions or calcium score &gt;0, pts in the control group (n=31) had intact coronary arteries. The groups did not differ in age or gender. 26 multiple linear logistic models for any subclinical atherosclerosis were developed based on obtained diagnostic features. Taking into account R-square = 0.344 (p=0.0008), the best fitting model was follows: subclinical coronary atherosclerosis= -1.576 + 0.234 x SCORE ≥5 % + 0.541 x hs CRP &gt;2 g / l +0.015 x heart rate (bpm) +0.311 family history of premature CVD. The developed algorithm had sensitivity of 63 % and specificity of 80 %.Conclusion The created diagnostic model diagnostic model suggests the presence of subclinical coronary atherosclerosis in patients with high / very high CV risk with a high degree of probability. This easy-to-use method can be used in routine clinical practice to improve risk stratification and management choices in high-risk pts.

[Current best practices and biobanking recomedations.]

The biobank is a structure established with the goal of long-term responsible storage of biological samples and the associated data for their further use in scientific and clinical research. The objectives of biobanking are the creation of unified recommendations on: the planning of premises and the selection of equipment for storage; development of management methods and staff training; standardization of methods for the collection, shipping, processing and storage of biomaterial of various origins, as well as methods for quality control and validation of the applied methods; creation and use of databases of information accompanying biospecimens. The lack of common standards for conducting the preanalytical phase has been the cause of low accuracy and poor reproducibility of research results. To date, a large number of guidelines and best practices have been published that provide an answer to a wide range of problems in organizing the biobanking process. The article provides an overview of the most famous biobanking guidelines that can be used to solve various research problems. Biobanking in Russia is actively developing. Since 1996 there is a work on the legislative regulation of biobanking activities, as a result of which a number of regulatory documents have been issued. An important stage in the development of biobanking in Russia was the establishment of the "National Association of Biobanks and Biobanking Specialists" (NASBio) in 2018, which included representatives of medical and research institutions, commercial firms, and qualified specialists in the field of biobanking. One of the key tasks of NASBio is the adaptation and implementation of the best biobanking practices in Russian research institutes and centers. The use of modern guidelines and best practices on biobanking will lead to an increase in the quality of research and publications.

P3351The new organizational scheme for research on rare and interesting clinical cases in cardiology

Introduction

There is a challenge to study rare and unusual diseases in cardiology. Patients with such cases often concentrate in large scientific medical centers, where implementation of new organizational research approaches may be useful to overcome this challenge.

Purpose

To develop and approbate new organizational scheme to study of rare and interesting clinical cases in cardiology.

Methods

The new organizational scheme for research on rare and interesting clinical cases in cardiology is based on three main interconnected teams: clinical cardiologists, scientific researchers, and biobanking specialists. In 2016 the joint team of experts in these areas developed: 1) criteria for selection of patients with rare and interesting clinical cases, 2) requirements for collection of biomaterial and data, 3) ethical rules, 4) logistics of all processes, 5) organization of teamwork of all participants from different departments, 6) promotion of the project and involvement of all clinicians of the medical scientific center.

Results

The teamwork of cardiologists, scientific researchers and biobanking specialists was organized. Cardiologists are responsible for selection of patients; scientific researchers - for formation and analysis of database; biobanking specialists - for standardization of biospecimens' collection, preparation and safe responsible storage, partly - for database formation. Special training for all participants of the project was conducted. It included issues of selection of patients; the procedure of informed consent signing and information encoding; logistics of interaction of clinical, scientific, and biobank's personnel; proper documentation etc. As a result since the start of the project from June 2016 to January 2019, biomaterial and depersonalized data were collected from 753 patients, including: early (<45 y.o. in men, <50 y.o. in women) development of coronary artery disease – 167, early (<50 y.o.) development of atrial fibrillation – 197, morbid obesity (BMI>40 kg/m2) - 71, primary electric heart diseases - 42, cardiomyopathies - 272, other rare diseases – 96 patients. The project is currently ongoing. This approach allows collecting and preserving valuable biomaterial and data for research in present and future. To date these materials have been already used for several research initiatives such as investigation of hypertrophic and non-compact cardiomyopathies, familial hypercholesterolemia; identification of novel genetic markers of type 2 diabetes and obesity; reports and publications about rare clinical cases.

Conclusion

The integrated teamwork of clinical cardiologists, scientific researchers and biobanking specialists in large scientific medical center gives qualitatively new opportunities: increase of the dynamicity, efficiency, standardization, and as a result, quality of present and future research on rare and interesting clinical cases in cardiology.

Levels of nitric oxide metabolites, adiponectin and endothelin are associated with SNPs of the adiponectin and endothelin genes

Adiponectin, endothelin and nitric oxide (NO) are major regulators of vascular function. An imbalance of vasoactive factors contributes to the onset and progression of atherosclerosis. Various single nucleotide polymorphisms (SNPs) are considered to be risk factors for coronary heart disease. However, the molecular mechanisms of their associations with the components of endothelial dysfunction are poorly understood. In the present study, rs17366743, rs17300539, rs266729, rs182052 and rs2241766 SNPs of the adiponectin (ADIPOQ) gene and rs2070699, rs1800542 and rs1800543 SNPs of the endothelin-1 (EDN1) gene were genotyped in 477 patients with coronary heart disease who were subjected to coronary angiography, in order to determine the presence or absence of coronary atherosclerosis. The serum levels of adiponectin, endothelin and stable metabolites of NO, (nitrate and nitrite NOx), were assayed and their associations with the SNP genotypes and coronary lesions were calculated. The results indicated that rs17366743 of the ADIPOQ gene and rs2070699 and rs1800543 of the EDN1 gene were associated with the levels of NOx in women, which in turn was associated with cardiovascular mortality. In men, rs182052 and rs266729 of the ADIPOQ gene were associated with adiponectin levels, whereas rs17366743 of the ADIPOQ gene was associated with endothelin levels. Additionally, these SNPs were indirectly associated with the prevalence of coronary lesions in men. Therefore, the tested SNPs can be considered potential risk factors that lead to imbalance of vasoactive mediators in a gender-specific manner and contribute to the development of clinical manifestations of atherosclerosis.

[An exploration of potential approaches to improve the diagnosis of subclinical atherosclerosis in patients with high cardiovascular risk]

PURPOSE

The search for optimal approaches to the diagnosis of subclinical atherosclerosis using a wide range of traditional and psychosocial risk factors (RFs), as well as clinical and instrumental diagnostic methods in patients (pts) with high or very high cardiovascular (CV) risk.

METHODS

This cross-sectional study enrolled52 pts, aged 40 to 65 years with high or very high CV risk (5-9 and ≥10% by the Systematic Coronary Risk Estimation Scale [SCORE], respectively). All participants underwent cardiac computed tomography (CT)angiography and calcium scoring. Traditional RFs (family history of premature CVD, smoking, overweight/obesity and abdominal obesity, hypertension, type 2 diabetes mellitus, lipids parameters (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides) and lipids-related markers (apolipoprotein A1, apolipoprotein B, ApoB/ApoA1 ratio), biomarkers of inflammation (high-sensitivity C-reactive protein [hs CRP], fibrinogen), indicator carbohydrate metabolism (glucose), ankle-brachial index, stress-test, carotid plaques according to ultrasound, arterial stiffness were evaluated in all pts. Psychological RFs were evaluated using Hospital Anxiety and Depression Scale and DS-14 for type D personality.

RESULTS

All pts were divided into 2 groups according to the CT angiography results: pts in the main group (n=21) had any non-obstructive lesions or calcium score &gt;0, pts in the control group (n=31) had intact coronary arteries. The groups did not differ in age or gender. It was found that patients with subclinical atherosclerosis significantly more often have a very high (≥10%) CV risk (42.9% vs.16.3%, p&lt;0.05), a long (≥5 years) history of arterial hypertension (47.6% vs. 12.9% , p&lt;0.01) and longer duration of antihypertensive therapy (61.9% vs. 29.0%, p&lt;0.05), higher heart rate in rest (87. ± 14 vs. 77 ± 10 beats/min, p&lt;0.01), increased arterial stiffness according to aortic pulse wave velocity (85.7% vs. 61.3%, p&lt;0.05) and high level of hs-CRP (100% vs. 90.3%, p&lt;0.05).

CONCLUSION

Using in routine clinical practice of additional anamnestic (hypertension lasting ≥ 5 years and the intake of any antihypertensive drugs) and clinical-instrumental parameters (high heart rate in rest, hs CRP and arterial stiffness in pts with high and very high CV risk increases effectiveness of early detection of subclinical atherosclerosis.

[Quality management in biobank. World tendencies and experience of biobank of FSI «NMRC for preventive medicine» of the Ministry of healthcare of Russia.]

This paper provides several definitions of the term "biobank"; a list of standards developed by the International Organization for Standardization (ISO) applicable to the activities of biobanks; analyzes the legal and ethical requirements; the Russian legal framework in the field of biobanking, the best international practices and recommendations; describes the experience of the development and implementation of quality management systems according to ISO 9001 in Biobanks established in different countries, and the experience of the Bank of Biological Material of the National Medical Research Center for Preventive Medicine of the Ministry of Healthcare of Russia. The ISO 20387 Biobanking Standard, released in August 2018, combined the knowledge and experience of specialists from around the world and defined the general requirements that must be fulfilled by biobanks and repositories wishing to guarantee their customers the high quality of the preanalytical stage of scientific research, biological samples and associated data. In 2019, the Russian version of this standard is expected. Documents of the quality management system provide the reproducibility of activities on the main storage processes and facilitates the process of incorporating a new employee; conducting internal and external audits; Biobank knowledge management - continuous staff education. The introduction of an effective quality management system into biobank activity warrants the high quality of biological samples, the standardized pre-analytical stage, reliable, regulated long-term storage of biomaterial and related information for use in research purposes today and in future.

[Elevated Level of the Natriuretic Peptide Among Adult Population in Regions Participating in the ESSE-RF Study and Its Association With Cardiovascular Diseases and Risk Factors]

AIM

to study associations between elevated blood plasma concentration of N-terminal pro-brain natriuretic peptide (NT-proBNP), risk factors and cardiovascular diseases (CVD) in samples of adult population of Russian Federation (RF) aged 25-64 years.

MATERIALS AND METHODS

We analyzed data of examination of representative samples of population of 5 regions of RF obtained within the framework of the multicenter ESSE-RF study (2012-2013). Number of examined subjects was 8 077 (3 176 men). Methods included use of standard questionnaire, measurements of height, body mass, blood pressure (BP), and plasma NT-proBNP level. The following CVD were included into analysis: arterial hypertension (AH), ischemic heart disease (IHD), atrial fibrillation (AF), and stroke.

RESULTS

Women compared to men had higher NT-proBNT concentration was higher in women compared to men, in both genders it rose with age. Overall 17.9 % of examinees had elevated NT-proBNT levels (14.2 and 20.3 % among men and women, respectively). Elevated NTproBNP level was associated in men with age, myocardial infarction, angina pectoris, ischemic ECG changes, left ventricular hypertrophy, AF, bradycardia, smoking, in women with age, IHD, ischemic ECG changes, AF, bradycardia, heart rate ≥80 bpm, BP ≥160/95 mm Hg.

CONCLUSION

In studied RF population elevated NT-proBNP level was significantly associated with gender, age, smoking, and CVD.

Direct labeling of serum proteins by fluorescent dye for antibody microarray

Analysis of serum proteome by antibody microarray is used to identify novel biomarkers and to study signaling pathways including protein phosphorylation and protein-protein interactions. Labeling of serum proteins is important for optimal performance of the antibody microarray. Proper choice of fluorescent label and optimal concentration of protein loaded on the microarray ensure good quality of imaging that can be reliably scanned and processed by the software. We have optimized direct serum protein labeling using fluorescent dye Arrayit Green 540 (Arrayit Corporation, USA) for antibody microarray. Optimized procedure produces high quality images that can be readily scanned and used for statistical analysis of protein composition of the serum.

[Combination of Visual and Metabolic Markers in Assessment of Probability of Presence and Severity of Atherosclerosis of Coronary Arteries]

AIM

to assess possibilities of the use of biochemical markers combined with data of methods of imaging of arterial atherosclerotic lesions for evaluation of risk of presence and severity of coronary atherosclerosis.

MATERIALS AND METHODS

We enrolled into this study patients (n=205, 136 men, 69 women, age 33-85 years, 94% on statin therapy) who underwent coronary angiography and carotid artery ultrasound dopplerography. Examination included determination of parameters of lipid profile and carbohydrate metabolism, markers of inflammation and metabolism of visceral adipose tissue. The severity of carotid artery atherosclerosis was estimated using mean common carotid artery intima-media thickness and atherosclerotic plaques presence. Severity of coronary atherosclerosis was evaluated using Gensini score.

RESULTS

We found association between a number of biomarkers and severity of coronary artery involvement. Presence of coronary atherosclerosis (Gensini score >0) was associated with male sex, carotid artery stenosis >45%, and adiponectin level <8.0 pg/ml. Overt coronary atherosclerosis (Gensini score more or equal 35) significantly correlated with intima-media thickness more or equal 0.9 mm, C-reactive protein level >3.0 mg/l and adiponectin level <8.0 pg/ml.

[Diagnostic Value of Biochemical Markers in Patients With Chronic Heart Failure With Reduced, Borderline and Preserved Left Ventricular Ejection Fraction]

PURPOSE OF THE STUDY

The study of the diagnostic value of biochemical markers of myocardial stress and inflammation in chronic heart failure (CHF) with different values of the ejection fraction (EF) of the left ventricle (LV).

MATERIAL AND METHODS

The cross-sectional study included 105 patients aged 24 to 84 years (mean 58+/-14 years) with stable chronic heart failure I-II NYHA functional class classification. The causes of CHF were ischemic heart disease (IHD) in 33% of patients and arterial hypertension (AH) - 67%. All patients received medical treatment: angiotensin-converting enzyme (ACE) - 76%, -blockers - 72%, diuretics - 100%, statins - 80%. The control group consisted of 35 healthy volunteers. All subjects identified blood natriuretic peptide (NT-proBNP, ANP), adiponectin, galectin-3, pentraxins-3 and growth differentiation factor-15 (GDF-15) by enzyme immunoassay (ELISA). All surveyed performed transthoracic echocardiography (Echo).

RESULTS

The blood NT-proBNP, ANP, galectin-3, pentraxins and GDF-3-15 in patients with chronic heart failure was significantly higher than in the control group (p<0.001 in all cases). In contrast, the level of adiponectin was significantly higher than in healthy individuals - 11.90 (11.39; 12.65) vs 7.73 (3.58; 8.86) ng/ml in patients with chronic heart failure (p<0.001). LVEF ranged from 30 to 55%, in 33% of patients it was >50%. Correlation analysis Spearman found strong correlations (p<0.001 for all markers) between LVEF and the content of all the biomarkers, while between the PV and the level of adiponectin is a positive correlation was found (r=0.862), and between the PV and the other biomarkers - reverse (r from -0.858 to -0.901). Multivariate linear regression analysis found the strongest correlation with the value of LVEF at pentraxin 3 and adiponectin. Subsequent ROC-analysis confirmed the diagnostic value of adiponectin in patients with heart failure and preserved ejection fraction. Thus, the level of adiponectin more than 8.3 ng/ml served as a prognostic factor for the presence of heart failure in patients with LVEF >50% with a sensitivity of 94.3% and a specificity of 92.9% (area under the curve 0.977; 95% confidence interval from 0.954 to 0.999; p<0.001).

CONCLUSIONS

Among the 6 studied biomarkers of myocardial stress and inflammation only adiponectin has diagnostic significance in patients with heart failure and preserved ejection fraction.

Ratios of leptin to insulin and adiponectin to endothelin are sex-dependently associated with extent of coronary atherosclerosis

OBJECTIVE

Noninvasive diagnostics of early stages of coronary artery disease and discrimination between various extents of vascular lesions in patients is an important clinical problem especially considering wide spread use of cholesterol lowering drugs that affect lipid and lipoprotein profiling. The main goal of our study was to evaluate applicability of new combinations of noninvasive biomarkers such as leptin to insulin and adiponectin to endothelin ratios, for detection of early stages of coronary atherosclerosis versus later stages of the disease.

PATIENTS AND METHODS

A number of previously validated serum biomarkers were tested in a group of 500 patients with coronary artery disease and examined for their association with severity of coronary lesion according to Gensini score determined by coronary angiography.

RESULTS

Lowest extent of coronary lesions was associated with significant increase in apoA-I levels and with significantly increased ratios of adiponectin to endothelin and leptin to insulin. In male but not in female patients, adiponectin to endothelin ratio below 7.0 was associated with Gensini score representing early to high coronary lesions (p = 0.02). In female but not in male patients, leptin to insulin ratio below 3.5 was associated with Gensini score representing early to high coronary lesions (p = 0.013).

CONCLUSION

Leptin to insulin and adiponectin to endothelin ratios are novel derived biomarkers useful for noninvasive diagnostics of initial stages of coronary lesions in patients with coronary artery disease.

[The application of lipoprint-system for analysis of sub-fractional spectrum of lipoproteins of blood serum.]

The lipoproteins of low and high density are presented by heterogeneous specter of particles differing by size, density, charge, composition and functional characteristics. The prevalence of small dense particles of lipoproteins of low and high density in blood plasma is associated with higher risk of development of coronary heart disease. The identification of subfractional spectrum of lipoproteins in clinical purposes is complicated because of requirement of expensive equipment and reagents and extended time of implementation. The lipoprint-system (Quantimetrix Lipoprint LDL/HDL System, USA) based on the vertical electrophoresis using 3% polyacrilamid gel, permits shortening time of sub-fractioning of lipoproteins up to three hours. In the spectrum of apoB-containing lipoproteins of very low density, intermediate density, C, B, A, lipoproteins of low density 1 and 2, small dense (lipoproteins of low density 3-7) are singled out. In the spectrum of lipoproteins of high density up to 10 sub-fractions associated in three groups and represented by large (lipoproteins of high density 1-3), intermediate (lipoproteins of high density 4-7) and small (lipoproteins of high density 8-10) particles are singled out. The article describes technique of identification of spectrum of particles of lipoproteins of low and high density in human blood serum. The conditions of implementation of experiments are presented. The advantages and limitations of technique are indicated. The number of examples of application of indices of sub-fractional spectrum of lipoproteins as additional markers of evaluation of aterogenity of lipid profile are presented. The conclusion is made concerning possibility of application of technique in clinical laboratory diagnostic.

[THE POSSIBILITIES OF APPLICATION OF TECHNOLOGY PROTEIN MICROARRAY (MICROCHIPS) FOR ANALYSIS OF PROTEIN COMPOSITION OF BLOOD SERUM]

The microchip technology represents convenient and relatively economic tool of analyzing specific biomarkers with the purpose to diagnose diseases, to evaluate effectiveness of therapy and to investigate signaling pathways. To analyze protein composition of blood serum certain types of finished microchips which were not applied previously on the territory of Russia. The detection from 2% to 5% out of matrix of chips depending on their variety was managed without preliminary depletion of serum (removal of proteins of major fractions). Hence, partial protein composition of blood serum can be analyzed with microchips even without preliminary removal of proteins of major fractions.

[Markers of visceral adipose tissue metabolic abnormalities in patients with coronary atherosclerosis in relation to the presence of type 2 diabetes mellitus]

AIM

To assess the specific features of visceral adipose tissue metabolism in patients with coronary atherosclerosis, complicated or uncomplicated type 2 diabetes mellitus (T2DM).

MATERIAL AND METHODS

A cohort of 429 patients (325 men and 104 women; mean age, 61.3±9.4 years) with coronary atherosclerosis who had been admitted to the National Research Centre for Preventive Medicine, Ministry of Health of Russia, to undergo coronarography (CG) and to receive high-tech treatments and met the criteria for being included in and excluded from this investigation, was examined. The Gensini scoring scale was used to estimate the magnitude of coronary atherosclerosis from CG RESULTS: Carotid artery duplex ultrasound scanning estimating the intima-media thickness was performed in 48% of the patients. DM was diagnosed from examination results (fasting plasma glucose ≥7.0 mmol/l and glycated hemoglobin >6.5%) and an endocrinologist's report. 94% of the patients took statins.

RESULTS

Overall, 18% of the examinees had DM that was 2.5 times more common in the women than in the men (32.7 and 13.2%, respectively (p=0.000). The diabetic and non-diabetic patients showed no significant differences in age: 62.9±8.3 and 60.9±9.6 years, respectively (p=0.105). There were statistically significant differences in the magnitude of coronary artery atherosclerosis according to the Gensini scale in relation to the presence of T2DM; thus, the median Gensini score was 48 in the diabetic patients and 46 in the persons with no signs of the disease (Mann-Whitney test; p=0.03). Analysis of adipokine levels showed that the median leptin level was significantly higher than that in the male patients with T2DM than in the persons with no signs of the disease. In the patients with T2DM, the median adiponectin level turned out to be significantly lower in both men and women.

CONCLUSION

The coronary atherosclerosis severity rated using the Gensini scale is shown to increase in the presence of T2DM. The probability of detecting obvious (>45%) carotid artery lesion is associated with the presence of DM in both men and women. The male patients with T2DM concurrent with coronary atherosclerosis are noted to have an elevated leptin level, but a lower adiponectin concentration was found in both the men and women.

Prevalence, components, and correlates of metabolic syndrome (MetS) among elderly Muscovites

The goal of this study is to estimate the prevalence of MetS, together with its components and correlates, among elderly Russians. Our population-based sample included randomly selected residents of Moscow aged 55 and older: 955 women with an average age of 67.6, and 833 men with an average age of 68.9. MetS was defined according to National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII). The prevalence of MetS was found to be 41.7% in women and 26.8% in men. It tended to decrease with age in men, but not in women. MetS was inversely related to education in women, but not in men. The most prevalent individual components of MetS were as follows: hypertension (64.4%), abdominal obesity (55%), and decreased high density lipoprotein cholesterol (HDL C) (46%) for women; and hypertension (71%) and fasting hyperglycemia (35.2%) for men. An elevated level of triglycerides (TG) was the rarest MetS component, affecting 23.5% of women and 22.1% of men. The higher female prevalence of MetS was attributable to abdominal obesity. MetS was found to be associated with markers of insulin resistance (IR), low-grade inflammation, and insufficient fibrinolysis. Although the metabolic burden is an important contributor to high levels of ill-health and cardiovascular mortality among elderly Russians (especially women), it does not explain why cardiovascular mortality is much higher in Russia than in other industrialized countries.

Effects of alcohol on the major steps of reverse cholesterol transport

The effects of moderate alcohol consumption on the capacity of blood sera to promote acceptance of cholesterol (C) from Fu5AH hepatoma cells, esterification of delivered free C, and transfer of produced cholesteryl esters to apolipoprotein (apo) B-containing lipoproteins have been studied. Twenty male subjects with relatively high (>50 mg/dl, n = 10) and low (<50 mg/dl, n = 10) high density lipoprotein (HDL) C levels consumed for eight weeks red grape wine (0.3 g ethanol/kg body mass per day). Alcohol consumption reduced total C and low density lipoprotein C levels in both groups of subjects. Low HDL C subjects showed an increase in HDL C, apo AI, apo AII, and lipoprotein (Lp) AI particle levels after alcohol consumption. Alcohol did not affect free C efflux from the cells. However, after the following period of substitution of alcohol with an isocaloric amount of red grape juice, cellular C efflux markedly reduced. While lecithin:cholesterol acyltransferase (LCAT) activity increased during alcohol consumption only in subjects with low HDL C, high HDL C subjects showed a significant decrease in cholesteryl ester transfer protein (CETP) activity. At the same time, alcohol consumption reduced the endogenous C esterification rate and increased the transfer of endogenous cholesteryl esters to apo B-containing lipoproteins in both groups. Thus, alcohol consumption in moderate doses enhanced the anti-atherogenicity of the serum lipoprotein spectrum, supporting more effective C efflux from peripheral cells and transport of accepted C to apo B-containing lipoproteins. The effects of alcohol on the reverse cholesterol transport depend on the initial HDL C level.