New Ideas for the Prevention and Treatment of Preeclampsia and Their Molecular Inspirations.

Preeclampsia (PE) is a pregnancy-specific disorder affecting 4-10% of all expectant women. It greatly increases the risk of maternal and foetal death. Although the main symptoms generally appear after week 20 of gestation, scientific studies indicate that the mechanism underpinning PE is initiated at the beginning of gestation. It is known that the pathomechanism of preeclampsia is strongly related to inflammation and oxidative stress, which influence placentation and provoke endothelial dysfunction in the mother. However, as of yet, no "key players" regulating all these processes have been discovered. This might be why current therapeutic strategies intended for prevention or treatment are not fully effective, and the only effective method to stop the disease is the premature induction of delivery, mostly by caesarean section. Therefore, there is a need for further research into new pharmacological strategies for the treatment and prevention of preeclampsia. This review presents new preventive methods and therapies for PE not yet recommended by obstetrical and gynaecological societies. As many of these therapies are in preclinical studies or under evaluation in clinical trials, this paper reports the molecular targets of the tested agents or methods.

Reliability of Rodent and Rabbit Models in Preeclampsia Research.

In vivo studies on the pathology of gestation, including preeclampsia, often use small mammals such as rabbits or rodents, i.e., mice, rats, hamsters, and guinea pigs. The key advantage of these animals is their short reproductive cycle; in addition, similar to humans, they also develop a haemochorial placenta and present a similar transformation of maternal spiral arteries. Interestingly, pregnant dams also demonstrate a similar reaction to inflammatory factors and placentally derived antiangiogenic factors, i.e., soluble fms-like tyrosine kinase 1 (sFlt-1) or soluble endoglin-1 (sEng), as preeclamptic women: all animals present an increase in blood pressure and usually proteinuria. These constitute the classical duet that allows for the recognition of preeclampsia. However, the time of initiation of maternal vessel remodelling and the depth of trophoblast invasion differs between rabbits, rodents, and humans. Unfortunately, at present, no known animal replicates a human pregnancy exactly, and hence, the use of rabbit and rodent models is restricted to the investigation of individual aspects of human gestation only. This article compares the process of placentation in rodents, rabbits, and humans, which should be considered when planning experiments on preeclampsia; these aspects might determine the success, or failure, of the study. The report also reviews the rodent and rabbit models used to investigate certain aspects of the pathomechanism of human preeclampsia, especially those related to incorrect trophoblast invasion, placental hypoxia, inflammation, or maternal endothelial dysfunction.

The Preeclamptic Environment Promotes the Activation of Transcription Factor Kappa B by P53/RSK1 Complex in a HTR8/SVneo Trophoblastic Cell Line.

Preeclampsia is a pregnancy disorder associated with shallow placentation, forcing placental cells to live in hypoxic conditions. This activates the transcription factor kappa B (NFκB) in maternal and placental cells. Although the role of NFκB in preeclampsia is well documented, its mechanism of activation in trophoblastic cells has been never studied. This study investigates the mechanism of NFκB activation in a first trimester trophoblastic cell line (HTR8/SVneo) stimulated by a medium containing serum from preeclamptic (PE) or normotensive (C) women in hypoxic (2% O2) or normoxic (8% O2) conditions. The results indicate that in HTR8/SVneo cells, the most widely studied NFκB pathways, i.e., canonical, non-canonical and atypical, are downregulated in environment PE 2% O2 in comparison to C 8% O2. Therefore, other pathways may be responsible for NFκB activation. One such pathway depends on the activation of NFκB by the p53/RSK1 complex through its phosphorylation at Serine 536 (pNFκB Ser536). The data generated by our study show that inhibition of the p53/RSK1 pathway by p53-targeted siRNA results in a depletion of pNFκB Ser536 in the nucleus, but only in cells incubated with PE serum at 2% O2. Thus, the p53/RSK1 complex might play a critical role in the activation of NFκB in trophoblastic cells and preeclamptic placentas.

Identification of placental genes linked to selective intrauterine growth restriction (IUGR) in dichorionic twin pregnancies: gene expression profiling study.

A linkage of dichorionic (DC) twin pregnancies with selective intrauterine growth restriction (IUGR) to alterations in placental gene expression is unclear. The aim of the study was to identify placental genes related to hypoxia, adipogenesis and human growth which may contribute to IUGR development. The study group (IUGR/AGA) comprised dichorionic (DC) twin pregnancies, where the weight of the twins differed by > 15%; in addition, one twin was small for gestational age (< 10th percentile-SGA) (IUGR) while the other was appropriate for gestational age (> 10th percentile-AGA). In the control group (AGA/AGA), both fetuses were AGA and their weights differed by < 15%. In the first step (selection), placental expression of 260 genes was analysed by commercial PCR profiler array or qPCR primer assay between six pairs of IUGR/AGA twins. In the second stage (verification), the expression of 20 genes with fold change (FC) > 1.5 selected from the first stage was investigated for 75 DC pregnancies: 23 IUGR/AGA vs. 52 AGA/AGA. The expression of Angiopoetin 2, Leptin and Kruppel-like factor 4 was significantly higher, and Glis Family Zinc Finger 3 was lower, in placentas of SGA fetuses (FC = 3.3; 4.4; 1.6; and - 1.8, respectively; p < 0.05). The dysregulation of gene expression related to angiogenesis and growth factors in placentas of twins born from IUGR/AGA pregnancies suggest that these alternations might represent biological fetal adaptation to the uteral condition. Moreover, DC twin pregnancies may be a good model to identify the differences in placental gene expression between SGA and AGA fetuses.

The profile of selected single nucleotide polymorphisms in patients with hypertension and heart failure with preserved and mid-range ejection fraction.

The study aimed to assess the clinical significance of selected single nucleotide polymorphisms (SNPs) in patients with diastolic heart failure (HF): inflammation [-174 G/C Interleukin -6 (IL-6) rs1800795, tumor necrosis factor (TNF)-608 G/A rs1800629], fibrosis [Arg25Pro transforming growth factor ß (TGF ß) rs1800471], endothelial function [-786 T/C nitric oxide synthase (NOS) rs2070744], glucose and lipid metabolism [Pro12Ala peroxisome proliferator activated receptor (PPAR)γ rs1801282], and vitamin D metabolism [cytochrome P450 27B1 (CYP27B1) C-1260A].110 patients with HF with preserved and mid-range ejection fraction (HFpEF and HFmrEF) were recruited. GG homozygotes in 174 G/C of IL6 polymorphism are characterized by higher values of estimated glomerular filtration rate based on the study Modification of Diet in Renal Disease (eGFR MDRD) and C allele in the NOS polymorphism and AA profile in C-1260A of CYP27B1 polymorphism correlated with a lower eGFR (MDRD). In multivariate analysis the CG genotype for 174 G/C of IL-6 and allele A in C-1260A of CYP27B1 are the only SNPs independently associated with worse course of HFpEF and HFmrEF. These data confirm the importance of the selected SNPs in aggravation and complications of hypertension.

Diagnostic utility of biomarkers of left ventricular stress in patients with aortic stenosis and preserved left ventricular ejection fraction.

INTRODUCTION: Aortic stenosis (AS) is the most common acquired valvular heart disease. The early identification of patients with severe AS is crucial. NT-proBNP is a well-known biomarker of pressure overload, and its role in patients with AS has been demonstrated in previous studies. Another, less well-known biomarker of pressure overload is sST2 protein, and its role in AS is unclear. AIM: To evaluate the utility of sST2 protein, NT-proBNP and selected clinical parameters in the assessment of degenerative AS severity in a population with preserved left ventricular ejection fraction (LVEF). MATERIAL AND METHODS: Sixty-nine consecutive patients (mean age: 68.42 ±12.58 years, 55.07% male) with symptomatic degenerative AS and preserved LVEF ≥ 45% were prospectively included. At enrollment complete transthoracic echocardiographic examination, ECG analysis, and standard laboratory tests including NT-proBNP were performed and blood samples for sST2 were obtained. RESULTS: There were 43 (62.32%) patients with severe AS. The multivariate stepwise linear regression models revealed that only systolic blood pressure (SBP), Sokolow-Lyon index and left ventricular end-diastolic diameter (LVEDD) were independently associated with severe AS. Spearman correlation coefficients analysis showed no correlations between sST2 levels and a mild to moderate correlation between NT-proBNP concentration and parameters of AS severity. However, levels of NT-proBNP (p = 0.1857) and sST2 (p = 0.7851) did not differentiate patients according to severity of AS. CONCLUSIONS: In the study population with degenerative AS and preserved LVEF neither the NT-proBNP nor sST2 concentrations can be used to differentiate patients according to the severity of AS.

Finding NEMO in preeclampsia.

BACKGROUND: The mechanism of preeclampsia and its way of inheritance are still a mystery. Biochemical and immunochemical studies reveal a substantial increase in tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6 concentrations in the blood of women with preeclampsia. The level of these factors is regulated by nuclear facxtor-kappa B, whose activation in a classical pathway requires inhibitory kappa B kinase gamma (known as NEMO or IKBKG). Moreover, NEMO can schedule between cytoplasma and the nucleus. In the nucleus, IKBKG interacts with other proteins, and thus, it is implicated in the regulation of different gene expressions, which are related to cell cycle progression, proliferation, differentiation, and apoptosis. OBJECTIVE: This is the first study investigating the association between the level of NEMO gene expression and the presence of preeclampsia. We tested the hypothesis that the simultaneous increase in NEMO gene expression both in the mother and her fetus may be responsible for the preeclampsia development. Moreover, the relationships between clinical risk factors of preeclampsia and the levels of NEMO gene expression in blood, umbilical cord blood, and placentas were investigated. STUDY DESIGN: A total of 91 women (43 preeclamptic women and 48 controls) and their children were examined. Real-time reverse transcription-polymerase chain reaction was used to assess the amount total NEMO messenger ribonucleic acid (mRNA) content and the mRNA level of each NEMO transcript from exons 1A, 1B, and 1C in maternal blood, umbilical cord blood, and placentas. Univariate analyses and correlation tests were performed to examine the association between NEMO gene expression and preeclampsia. RESULTS: Newborn weight and height, maternal platelet number, and gestational age (week of delivery) were lower in the group of women with preeclampsia than controls. NEMO gene expression level was found to be almost 7 times higher in the group of women with preeclampsia than healthy controls. The correlation analysis found that a simultaneous increase in the expression level of total NEMO mRNA in maternal blood and the mRNA for total NEMO (Rs = 0.311, P < .05), transcripts 1A (Rs = 0.463, P < .01), 1B (Rs = 0.454, P < .01), and 1C (Rs = 0.563, P < .001) in fetal blood was observed in preeclamptic pregnancies. In addition, the mRNA levels for total NEMO and transcripts 1A, 1B, and 1C were lower in placentas derived from pregnancies complicated by preeclampsia. CONCLUSION: Simultaneous increase of NEMO gene expression in maternal and fetal blood seems to be relevant for preeclampsia development. The results of our study also suggest that a decreased NEMO gene expression level in preeclamptic placentas may be the main reason for their intensified apoptosis.

Differences in gene expression and alterations in cell cycle of acute myeloid leukemia cell lines after treatment with JAK inhibitors.

Janus kinase (JAK) inhibitors are a promising treatment strategy in several hematological malignancies and autoimmune diseases. A number of inhibitors are in clinical development, and two have already reached the market. Unfortunately, all of them are burdened with different toxicity profiles. To check if the JAK inhibitors of different selectivity evoke different responses on JAK2-dependent and independent cells, we have used three acute myeloid leukemia cell lines with confirmed JAK2 mutation status. We have found that JAK inhibitors exert distinct effect on the expression of BCLXL, CCND1 and c-MYC genes, regulated by JAK pathway, in JAK2 wild type cells in comparison to JAK2 V617F-positive cell lines. Moreover, cell cycle analysis showed that inhibitors alter the cycle by arresting cells in different phases. Our results suggest that observed effect of JAK2 inhibitors on transcription and cell cycle level in different cell lines are associated not with activity within JAK family, but presumably with other off-target activities.

Single sST2 protein measurement predicts adverse outcomes at 1-year follow-up in patients with chronic heart failure.

INTRODUCTION: sST2 protein is a new biomarker. Its prognostic value in chronic heart failure (CHF) is still unclear. OBJECTIVES: The aim of the study was to evaluate the value of sST2 protein in patients with CHF during 1-year follow-up after hospitalization for prediction of adverse events: cardiovascular death, rehospitalization, an increase in diuretic doses, and/or worsening of the New York Heart Association functional class, defined as the composite endpoint. PATIENTS AND METHODS: The study involved 145 consecutive patients (mean age, 62.16 ±11.25 y; men, 82.76%) with left ventricular (LV) ejection fraction of 30% or less and symptomatic CHF. We analyzed clinical and biochemical data along with the serum concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and sST2. The optimal cut-off points for significant predictors of the composite endpoint were determined using receiver operating characteristi c curves. RESULTS: Patients with elevated levels of sST2 and NT-proBNP had more than a 4-fold higher risk of composite endpoint (odds ratio [OR], 4.033; 95%CI, 1.540-10.559) compared with patients in whom both biomarkers were below the cut-off points. The C-statistic for predicting the composite endpoint was improved when both biomarkers were incorporated into the model (C-statistic, 0.692; P = 0.0001) compared with an individual analysis for NT-proBNP (C-statistic, 0.606; P = 0.009) and sST2 (C-statistic, 0.613; P = 0.003). Moreover, after the addition of sST2 to NT-proBNP, the continuous net reclassification improvement index (OR, 0.256; 95% CI, 0.090-0.401; P = 0.007) and the integrated discrimination improvement index (OR, 0.104; 95% CI 0.011-0.221; P = 0.007) significantly improved. CONCLUSIONS: A single measurement of sST2 levels on admission in patients with poor LV systolic function and stable CHF is useful in short-term risk stratification and, in combination with NT-proBNP, it could be more useful in identifying patients with unfavorable c ourse of CHF.

Genetic polymorphisms and the risk of myocardial infarction in patients under 45 years of age.

This study investigates the potential role of 17 chosen polymorphisms in 15 candidate genes and the risk of myocardial infarction in patients under 45 years of age. The study consists of 271 patients with myocardial infarction and 141 controls. The analysis of genetic polymorphisms was performed using the PCR-RFLP method. Of the chosen polymorphisms, two (Leu125Val PECAM1 and A1/A2 FVII) are related to myocardial infarction and two (C677T MTHFR and 5A/6A MMP3) to advanced stenosis in arterial vessels (> 75%). We also found that the frequency of some combinations among the analyzed genes and environmental factors varied between the patient and control groups.

Genetic variation in gsα protein as a new indicator in screening test for vasovagal syncope.

BACKGROUND: A quantitative history using Calgary syncope syndrome score (CSSS) is able to define the likely cause of syncope, but there is still a lack of diagnostic screening tests for vasovagal syncope (VVS). The aim of the present study was to develop a screening test for VVS on the basis of CSSS and the relationship between polymorphic variants of the G-system signaling protein genes and tilting results. METHODS AND RESULTS: From 730 syncopal patients, 307 consecutive subjects without structural and electrical abnormalities were genotyped and examined on blood pressure (BP) and tilt testing. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism in genes encoding Gsα-protein GNAS1 (rs7121), G-protein ß 3 subunit (rs5443) and the cardiac regulator of G-protein signaling RGS2 (rs4606). The control group consisted of 100 healthy volunteers with a negative history of syncope. From multivariate regression analysis, being a carrier of 393T GNAS1 (odds ratio [OR], 2.29) and systolic BP (OR, 0.98) remained as independent factors associated with positive tilt results. The resultant screening test for VVS consisted of the following: carrier of 393T GNAS1; systolic BP < 131 mm Hg (from the receiver operating characteristic [ROC] curve); and CSSS ≥-2. Using ROC curve analysis for systolic BP and CSSS, 2 final models for the screening test were constructed: highest sensitivity (89%) and highest specificity (99%). CONCLUSIONS: The novel screening test including the variation of Gsα protein gene seems to be helpful to identify tilt-induced vasovagal patients.

Prognostic significance of Wnt-1, ß-catenin and E-cadherin expression in advanced colorectal carcinoma.

Wnt/ß-catenin pathway plays an important role in initiation and progression of colorectal oncogenesis. The aim of this study was to determine expression and localization of E-cadherin, ß-catenin and Wnt-1 proteins in colorectal tumors. Expression of ß-catenin, E-cadherin and Wnt-1 was determined by immunohistochemistry on advanced colorectal cancers. Abnormal expression of E-cadherin, ß-catenin, Wnt-1 was observed. Additionally, we revealed correlations between levels of studied proteins and histoclinical data. In multivariate analysis nuclear ß-catenin, higher carcinoembryonic antigen serum level before treatment, female sex and tumor localized in colon or rectum were independent unfavorable prognostic factors. These findings support the hypothesis that Wnt/ß-catenin pathway plays an important role in advanced colorectal carcinoma.

Plasma levels of angiogenic factors and circulating endothelial cells in essential thrombocythemia: correlation with cytoreductive therapy and JAK2-V617F mutational status.

Recent studies have shown that angiogenesis plays an important role in the biology of hematological malignancies including essential thrombocythemia (ET). Using cytofluorimetric analysis, the levels of angiogenic factors, as well as the number of circulating endothelial cells (CECs), were determined in 65 patients with ET, including 33 previously untreated and 32 receiving cytoreductive therapy. Correlations between markers of angiogenesis and JAK2-V617F mutational status were also assessed. We found significantly higher levels of vascular endothelial growth factor (VEGF) and markedly decreased levels of placental growth factor in untreated patients with ET with respect to control subjects. VEGF levels were significantly increased in patients with white blood count >8.7 (x 10(9)/L) vs. <8.7 (x 10(9)/L). Furthermore, the levels of VEGF in patients on hydroxyurea (HU) therapy were markedly lower than in untreated patients. It was also demonstrated that the number of all CEC subpopulations (resting, activated, apoptotic, and circulating precursor endothelial cells) was increased in patients with ET in relation to controls, regardless of the JAK2-V617F status, and was not affected by cytoreductive treatment. In conclusion, our study highlights the possible role of angiogenesis in the pathophysiology of ET. It provides evidence that the number of CECs is elevated independently of JAK2-V617F status and is not down-regulated by HU or anagrelide therapy. Our data suggest that VEGF levels are particularly elevated in patients with high leukocytosis. Further investigation should be undertaken to determine the possible role of antiangiogenic therapy in ET.

Circulating endothelial cells in essential thrombocythemia and polycythemia vera: correlation with JAK2-V617F mutational status, angiogenic factors and coagulation activation markers.

Angiogenesis plays an important role in the biology of hematological malignancies, including essential thrombocythemia (ET) and polycythemia vera (PV). Some data suggests that it has a role in the pathogenesis of thrombosis, the major clinical problem in ET and PV. The number of different subpopulations of circulating endothelial cells (CECs), plasma levels of vascular endothelial growth factor (VEGF), soluble vascular endothelial growth factor receptor 1 and 2 (sVEGFR-1,2) and placenta growth factor (PlGF) were determined in 30 patients with ET and 16 patients with PV. Correlations between angiogenesis and JAK2-V617F mutational status, risk factors for thrombosis and coagulation activation markers were also assessed. The number of CEC subpopulations, were markedly higher in ET and PV patients, irrespective of JAK2-V617F status, when compared to the control group. The median values of activated CECs were markedly higher in PV patients with WBC >8.7 (x10(9)/l). Significantly higher VEGF plasma levels were found in ET patients and a similar trend was seen in PV patients in relation to healthy volunteers. The plasma levels of sVEGFR-1 were significantly higher, and PlGF levels markedly lower, in the ET and PV group than in controls. Our study also demonstrated markedly increased levels of D-dimer and TAT complexes in the patient groups. In conclusion, we found that angiogenesis, as measured by CEC numbers, is increased in ET and PV patients regardless of JAK2-V617F mutational status. Our results demonstrated that angiogenic cytokines interact with known thrombotic risk factors. We confirmed the coagulation activation in ET and PV patients but found no differences in levels of coagulation activation markers in relation to JAK2-V617F mutational status.

Genetic variability and the risk of myocardial infarction in Poles under 45 years of age.

INTRODUCTION: Myocardial infarction is caused by the obstruction of an artery in places of atherosclerosis plaque rupture. Endothelial cells during their activation express chemoattractant and adhesion molecules whereas infiltrating inflammatory cells produce enzymes, predisposing a lesion to rupture. MATERIAL AND METHODS: We investigated the correlation between polymorphisms in the human genes E-selectin (Ser128Arg), ICAM1 (K469E), OLR1 (K167N), MMP1 (1G/2G) and MMP3 (-1612 5A/6A) and the risk of MI in young Poles under 45 years. There was no significant difference in the frequency of single nucleotide polymorphism (SNP) of the studied genes E-selectin (Ser128Arg), ICAM1 (K469E), OLR1 (K167N) and MMP3 (-1612 5A/6A) between patients with MI and controls. RESULTS: The analysis of the association of the 1G2G polymorphism with the risk of myocardial infarction indicated an odds ratio (OR) of 5.68 (95% confidence interval [95% CI] 2.60 to 12.36). Other factors associated with myocardial infarction were: smoking (OR 4.12; 95% CI 1.63-10.44), male sex (OR 16.02; 95% CI 5.90-43.46), hypercholesterolaemia (OR 2.74; 95% CI 1.29-5.83) and arterial hypertension (OR 4.56; 95% CI 1.66-14.47). CONCLUSIONS: We found that only MMP1 1G/2G polymorphism is associated with myocardial infarction in the Polish population of individuals younger than 45 years. Clinical factors seemed to play a greater role in the analysed group.

Genetic insight into syncopal tilted population with severe clinical presentation.

UNLABELLED: An impairment of cardiovascular reflexes may be the result of functional alterations in the G proteins intracellular signaling produced by functional genes' polymorphisms. The aim was to evaluate the relationships between single nucleotide polymorphisms in genes encoding G-proteins signaling pathways and syncopal patients with severe clinical manifestation. METHODS AND RESULTS: From 307 syncopal patients free from any other diseases 83 (27%) had at least one malignant episode of syncope with a significant injury as fractures. There was 1.9 malignant spells per patient. All patients were tilted and genotyped by polymerase chain reaction followed by restriction fragment length polymorphism method. 74 healthy volunteers with negative history of syncope constituted the control group were also genotyped. Following polymorphisms were detected: C393T in gene encoding the alfa-subunit of Gs-protein (GNAS1), C825T of gene for G-protein beta 3 subunit (GNB3) and C1114G for the gene of cardiac regulator of G-protein signaling (RGS2). We found an association with lower risk of malignant syncope in positive tilting patients during passive phase of the test compared to NTG-enhanced (OR 0.38; 95% CI 0.15-0.95; P=0.04). No difference between healthy controls and patients in the alleles frequency was found (P>0.05). Neither the 393T allele of GNAS1 and 825T allele of GNB3 nor 1114G allele of RGS2 was associated with enhanced risk of severe clinical manifestation (P>0.05). CONCLUSIONS: The studied single nucleotide polymorphisms of genes encoding G-proteins signaling pathways seem to be not connected with the severe clinical manifestation of syncope.

Mutation T/C,Ile 131 of the gene encoding the alfa subunit of the human Gs protein and predisposition to vasovagal syncope.

BACKGROUND: Mutation T/C inside codon 131 of the gene encoding the alpha subunit of Gs protein (GNAS1) causes the increased activation of adenyl cyclase, which plays an important role in cardiovascular regulation. The aim of the present study was to evaluate GNAS1 T/C,Ile 131 mutation's manifestation in syncopal patients regarding head-up tilt test (HUTT) results. METHODS AND RESULTS: In 137 syncopal patients (without any other diseases) the silent T/C,Ile 131 mutation within the GNAS1 codon on chromosome 20 q was identified. This mutation consists of the presence (+) or absence (-) of a target site for endonuclease FokI (Promega). Ninety-six patients (70%) with positive HUTT had a higher FokI+ allele frequency compared with those with negative tilting results (49% vs 27%, X(2)=12.05; p<0.001). In positive tilted patients, the studied mutation had significant influence on blood pressure (p<0.05). When comparing positive HUTT with vasodepressore component, cardioinhibition results and negative HUTT, the frequencies of the FokI+ allele were decreased among these groups: 53%, 36% and 27%, respectively. CONCLUSIONS: An association between positive tilting and mutation C/T,Ile 131 within the GNAS1 codon was found. The predisposition to vasovagal syncope seems to be associated with the GNAS1 FokI+ allele.

Vasovagal syncope patients and the C825T GNB3 polymorphism.

OBJECTIVE: The G protein is responsible for signal intracellular transduction and participates in cardiovascular reflexes. C825T polymorphism of the gene encodes the B3 subunit of G protein (GNB3) and causes the increased intracellular signal transduction. The aim was the evaluation GNB3 C825T polymorphism manifestation in vasovagal patients with no other diseases. METHODS: In 68 positive tilted patients genomic DNA was extracted from blood using an extraction kit. The GNB3 C825T polymorphism was diagnosed by restriction of the PCR amplicon with BseDI (MBI Fermentas). All patients were genotyped and next analyzed in regard to typical vasovagal history. RESULTS: The prevalence of genotype CC was 38%. Genotypes CT and TT were found equally in 31% of cases. The C allele in comparison to the T allele appeared in 54% vs 46% (p>0.05). Typical vasovagal history was present in 83% of patients. The frequency of GNB3 825T allele was significantly higher in patients with non-typical vasovagal history than in group with typical history (p<0.001). CONCLUSIONS: Genotype CC GNB3 is the most popular in vasovagal patients. The predisposition to vasovagal syncope seems to be not associated with the GNB3 825T allele. Further studies are planned to clarify the genotype/phenotype relationship in vasovagal patients.