Maria Skerenova

Platelet aggregation abnormalities in patients with fetal losses: the GP6 gene polymorphism.

OBJECTIVE To evaluate the GP6 gene polymorphism in patients with sticky platelet syndrome (SPS) and fetal loss. DESIGN Genetic association study. SETTING Perinatal center. PATIENT(S) Twenty-seven patients with SPS, manifested as fetal loss, and 42 control subjects without SPS and no history of fetal loss and thrombosis. INTERVENTION(S) SPS was diagnosed by platelet aggregometry (PACKS-4 aggregometer; Helena Laboratories). Seven single-nucleotide polymorphisms (SNPs) of the GP6 gene were evaluated. MAIN OUTCOME MEASURE(S) Occurrence of SNPs of the GP6 gene in SPS patients versus control subjects. RESULT(S) We found a higher occurrence of three SNPs of the GP6 gene in SPS patients versus control subjects (rs1671153: 0.204 vs. 0.048, odds ratio [OR] 5.116, 95% confidence interval [CI] 1.536-17.03; rs1654419: 0.204 vs. 0.071, OR 3.326, 95% CI 1.149-9.619; rs1613662: 0.204 vs. 0.071, OR 3.326, 95% CI 1.149-9.619). The haplotype analysis showed a significantly higher occurrence of two haplotypes (CTGAG in haplotype 5: 0.185 vs. 0.059, OR 3.568, 95% CI 1.142-11.14; and CGATAG in haplotype 6: 0.204 vs. 0.048, OR 4.961, 95% CI 1.488-16.53). CONCLUSION(S) Our results, especially the higher occurrence of haplotypes CTGAG and CGATAG in SPS patients, support the idea that GP6 gene polymorphism may be associated with platelet hyperaggregability, a possible cause of fetal loss.

Different models of inheritance in selected genes in patients with sticky platelet syndrome and fetal loss.

INTRODUCTION The aim of this study was to evaluate the genetic variability of selected single nucleotide polymorphisms (SNPs) within GAS6 and PEAR1 genes and explore the association between selected SNPs and risk for fetal loss in women with sticky platelet syndrome (SPS). MATERIALS AND METHODS We examined 23 female patients with SPS and history of spontaneous abortion, and 42 healthy women who served as controls. The diagnosis of SPS was established by light transmission aggregometry according to methods and criteria developed by Mammen et al. We also assessed four SNPs within the GAS6 gene (rs7400002, rs1803628, rs8191974, rs9550270) and two SNPs within PEAR1 gene (rs12041331, rs12566888). RESULTS We identified two SNPs within PEAR1 gene (rs12041331, rs12566888) and one SNP within GAS6 gene (rs9550270) that have higher occurrence in SPS patients with history of abortion. An increased risk for abortion was observed in carriers of the rs7400002 within GAS6 gene. Conversely, we found that the T allele of PEAR1 c. -9-4663G > T polymorphism appears to be protective for fetal loss. CONCLUSION Our results support the idea that genetic variability of GAS6 and PEAR1 genes may be associated with platelet hyperaggregability. The study also suggests a possible polygenic type of SPS heredity.

TNF-α G308A Gene Polymorphism Has an Impact on Renal Function, Microvascular Permeability, Organ Involvement and Severity of Preeclampsia

Background/Aims: Preeclampsia (PE) is a life-threatening complication of pregnancy that is associated with a high rate of maternal and perinatal morbidity and/or mortality worldwide. If untreated, it can progress to eclampsia, which can result in the death of the mother, the fetus or both. The etiology of PE is still uncertain; however, recently the role of the immune system has gained in importance. The role of tumor necrosis factor-α (TNF-α), a cytokine involved in inflammation processes, has been widely investigated in obstetric disorders. The aims of the present study were to investigate the effect of TNF-α gene G308A (rs1800629) polymorphism on disease risk, renal function, microvascular permeability, endothelial cell dysfunction and organ involvement in women with PE. Methods: Initially, 102 3rd-trimester pregnant women (preeclamptic cases and healthy controls) with singleton pregnancy were invited for participation, of which 76 were genotyped for TNF-α G308A polymorphism and evaluated for plasma levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), fibronectin and TNF-α, which were tested for correlations with the profile of PE. The odds ratio (OR) and 95% confidence intervals obtained from unconditional logistic regression were used to test the association between the TNF-α polymorphism and PE risk. For continuous variables, we applied Students t test and, for categorical variables, the Pearson χ2 or Fishers exact test. The two-way ANOVA test with Bonferroni correction was used in multivariate analyses. Results: The A allele was more frequent in cases than controls (22.4 vs. 13.2%), which increased disease risk (OR = 2.73). Maternal serum levels of TNF-α, sVCAM-1 and fibronectin were significantly increased in cases (855.8 ± 385.1 pg/ml, 1,243 ± 671 ng/ml, 0.308 ± 0.231 g/l, respectively) compared to controls (301.1 ± 156.1 pg/ml, 651 ± 250 ng/ml, 0.218 ± 0.101 g/l, respectively; p < 0.0001, p < 0.0001 and p = 0.031, respectively), and these levels showed an increasing trend with the mutant allele genotype. Moderate and severe proteinuria was higher in rs1800629 allele A subjects compared to G/G carriers (53.8 vs. 14.3% (p < 0.05) and 13.0 vs. 4.7% (p < 0.01), respectively). The adverse effect of rs1800629 allele A on renal function was confirmed by increased plasma creatine levels, urinary protein excretion and lower tubular resorption rate in preeclamptic patients. Moreover, rs1800629 allele A preeclamptic carriers showed higher serum levels of fibronectin and sVCAM-1 compared to G/G homozygotes. Conclusion: This study reveals a possible association between clinical and laboratory manifestations of PE and the TNF-α gene G308A (rs1800629) polymorphism.

Progress in the Understanding of Sticky Platelet Syndrome.

&NA; The knowledge on the etiology of thrombosis has increased tremendously over the past decades. Nevertheless, Virchow triad is still traditionally invoked to explain mechanisms leading to thrombosis, alleging concerted roles for abnormalities in blood composition, vessel wall components, and blood flow in the development of arterial and venous thrombosis. Recent decades have been focused primarily on describing abnormalities in blood composition, including defects of coagulation proteins and platelets. Although defects of coagulation factors are relatively well‐described in the literature, prothrombotic platelet disorders are still less understood. One such defect, the Wien‐Penzing defect was first described in 1991. Another platelet defect is sticky platelet syndrome (SPS). In this article, we review information about SPS, and we propose a new definition and standardization of diagnostic criteria. We also attempt to explain the causes and consequences of this condition.

Genetic variations of the GP6 regulatory region in patients with sticky platelet syndrome and miscarriage.

Introduction: Thrombophilia increases the risk of venous thrombosis during pregnancy and may predispose to gestational vascular complications. Objective: The aim of this study is to evaluate the variability of GP6 regulatory regions in a group of patients with platelet hyperaggregability manifested as miscarriage compared with control subjects. Methods: We examined 27 female patients with platelet hyperaggregability and history of spontaneous abortion and 42 healthy women. Platelet hyperaggregability was established by light transmission aggregometry. We also assessed eight SNPs within the GP6 gene. Results: We found a higher occurrence of three SNPs in patients with platelet hyperaggregability and history of miscarriage (rs1671152, rs1654433, rs1671215). The haplotype analysis showed a significant higher occurrence of two haplotypes (ACGG, CCGT). Conclusions: Our results support the idea that genetic variability of GP6 regulatory regions can be associated with platelet hyperaggregability – a possible cause of miscarriage.

Sticky platelet syndrome: an important cause of life-threatening thrombotic complications.

Sticky platelet syndrome (SPS) is a prothrombotic thrombocytopathy with familial occurrence, characterized by hyperaggregability of platelets in response to adenosine diphosphate (ADP), epinephrine (EPI) or both. The syndrome has been identified in approximately 21% of unexplained arterial thrombotic episodes, regarded to be the most common thrombophilia in arterial thrombosis and 13.2% of unexplained venous thromboembolism (VTE). The relatively young age at the first manifestation, relation to fertility and pregnancy, seriousness of the symptoms, easy and effective management of the disorder indicate to the necessity to take it into account in the differential diagnosis of the underlying cause of the thrombotic event. As the various localizations of the thrombosis in SPS have been reported, its management often requires a multidisciplinary approach. This review deals with the clinical aspects of thrombophilia, its etiopathogenesis, diagnosis as well as novel advances in the treatment and outlines the challenges for the further research.

Activity of coagulation factor XI in patients with spontaneous miscarriage: The presence of risk alleles

Abstract The aim of this study was to compare the activity of coagulation factor XI (FXI) between patients with spontaneous miscarriage versus control group with no history of miscarriage and thrombosis, and then we evaluated the occurrence of risk alleles in the relation to miscarriage. FXI activity was determined using a coagulometer (Sysmex, CA 1500, Japan). Single nucleotide polymorphisms (SNPs) of F11 and CYP4V2 genes were evaluated. We examined 55 patients versus 31 control subjects. We found significantly higher activity of FXI (p = 0.04) in patients versus control subjects. The occurrence of two SNPs (rs2289252 and rs2036914) of the F11 gene and SNP (rs13146272) of CYP4V2 gene was not significantly different between both groups. Increased activity of FXI may be a potential risk factor for miscarriage. High activity of FXI diagnosed in women with history of miscarriage is not probably caused by the presence of studied SNPs.

Association of Genetic Variability in Selected Genes in Patients With Deep Vein Thrombosis and Platelet Hyperaggregability

The aim of this study was to evaluate the genetic variability of the selected single nucleotide polymorphisms (SNPs) and examine the association between these SNPs and risk for deep vein thrombosis (DVT) in patients with sticky platelet syndrome (SPS). We examined 84 patients with SPS and history of DVT and 101 healthy individuals. We were interested in 2 SNPs within platelet endothelial aggregation receptor 1 (PEAR1) gene (rs12041331 and rs12566888), 2 SNPs within mkurine retrovirus integration site 1 gene (rs7940646 and rs1874445), 1 SNP within Janus kinase 2 gene (rs2230722), 1 SNP within FCER1G gene (rs3557), 1 SNP within pro-platelet basic protein (rs442155), 4 SNPs within alpha2A adrenergic receptor 2A (ADRA2A; rs1800545, rs4311994, rs11195419, and rs553668), and 1 SNP within sonic hedgehog gene (rs2363910). We identified 2 protective SNPs within PEAR1 gene and 1 risk SNP within ADRA2A gene (PEAR1: rs12041331 and rs12566888; ADRA2A: rs1800545). A haplotype analysis of 4 SNPs within ADRA2A gene identified a risk haplotype aagc (P = .003). Moreover, we identified 1 protective haplotype within PEAR1 gene (AT, P = .004). Our results support the idea that genetic variability of PEAR1 and ADRA2A genes is associated with platelet hyperaggregability manifested as venous thromboembolism. The study also suggests a possible polygenic type of SPS heredity.

Glycoprotein VI Gene Variants Affect Pregnancy Loss in Patients With Platelet Hyperaggregability

The aim of our study was to evaluate GP6 gene in patients with sticky platelet syndrome (SPS) and fetal loss. Platelet aggregability was tested with platelet-rich plasma using PACKS-4 aggregometer (Helena Laboratories). High-resolution melting analysis on LightCycler 480 II (Roche Diagnostics) was used for single-nucleotide polymorphism (SNP) genotyping. We examined 64 patients with SPS and 54 control participants. We found significantly higher occurrence of 5 SNPs in patients with SPS versus controls (rs1671152, rs1654433, rs1613662, rs1654416, and rs2304167). Moreover, the haplotype analysis showed a significantly higher occurrence of 7 haplotypes in patients with SPS compared to controls (acgg and aagg in GP6_5reg haplotype; ccgt in GP6_3reg haplotype; gg and ta in GP6_REG haplotype; SKTH and PEAN in GP6_PEAN haplotype). Our results, especially higher occurrence of 4 nonsynonymous variants within the coding region, support the idea that GP6 polymorphisms are associated with the platelet hyperaggregability accompanied by fetal loss.