Polymorphisms in the factor VII gene and ischemic stroke in young adults

Current and potentially novel antithrombotic treatment in acute ischemic stroke

Acute ischemic stroke (AIS) is the most common type of stroke and requires immediate reperfusion. Current acute reperfusion therapies comprise the administration of intravenous thrombolysis and/or endovascular thrombectomy. Although these acute reperfusion therapies are increasingly successful, optimized secondary antithrombotic treatment remains warranted, specifically to reduce the risk of major bleeding complications. In the development of AIS, coagulation and platelet activation play crucial roles by driving occlusive clot formation. Recent studies implicated that the intrinsic route of coagulation plays a more prominent role in this development, however, this is not fully understood yet. Next to the acute treatments, antithrombotic therapy, consisting of anticoagulants and/or antiplatelet therapy, is successfully used for primary and secondary prevention of AIS but at the cost of increased bleeding complications. Therefore, better understanding the interplay between the different pathways involved in the pathophysiology of AIS might provide new insights that could lead to novel treatment strategies. This narrative review focuses on the processes of platelet activation and coagulation in AIS, and the most common antithrombotic agents in primary and secondary prevention of AIS. Furthermore, we provide an overview of promising novel antithrombotic agents that could be used to improve in both acute treatment and stroke prevention.

Genetic Variants Associated with High Susceptibility of Premature Ischemic Stroke

Background

Several polymorphisms had been associated with an increased risk of ischemic stroke, but results are inconclusive. The aim of this study was to examine the association between AGTR1 A1166C and TSP-1 N700S polymorphisms and ischemic stroke in a young Mexican population.

Methods

In a case-control study, 250 patients ≤ 45 years of age with ischemic stroke and 250 controls matched by age and gender were included. The polymorphisms were determined in all participants by polymerase chain reaction.

Results

There were statistical differences in genotype distribution (p = 0.01) and allele frequency (p = 0.001) of AGTR1 A1166C polymorphism. In contrast, there was a similar genotype distribution (p = 0.96) and allele frequency (p = 0.76) of the TSP1 N700S genetic variant between groups. Hypertension (p = 0.03), smoking (p = 0.02), and family history of atherothrombotic disease (p = 0.04) were associated with stroke, but not diabetes (p = 0.30) and dyslipidemia (p = 0.08).

Conclusions

This is the first study in Mexican population to explore several genetic variants in young patients with ischemic stroke. Our results suggest that polymorphisms in the renin-angiotensin-aldosterone system could contribute to premature hypertension, endothelial dysfunction, atherothrombosis, vasoconstriction, smooth muscle cell migration, and proliferation. In contrast, polymorphisms in the coagulation factors are not associated with ischemic stroke. Environmental factors such as diabetes and dyslipidemia could be less important in the pathogenesis of ischemic stroke at a young age. We suggest that those polymorphisms should be determined in individuals with a family history of thrombosis to avoid the stroke development. Therefore, genotype-environmental combination could determine several possible phenotypes at different moments in life.

Systematic Investigation of the Effect of Powerful Tianma Eucommia Capsule on Ischemic Stroke Using Network Pharmacology

Background

Ischemic stroke (IS) is a serious disease with a high rate of death and disability, and a growing number of people are becoming victims. Existing drugs not only have limited therapeutic effects but also have obvious side effects. Most importantly, drug resistance due to long-term or improper use of drugs is detrimental to patients. Therefore, it is urgent to find some alternative or supplementary medicines to alleviate the current embarrassment. Powerful Tianma Eucommia Capsule (PTEC) is mainly used to treat IS in China for thousands of years; however, the molecular mechanism is not clear.

Methods

Pharmacology ingredients and target genes were filtered and downloaded from websites. A pharmacology ingredient-target gene network was constructed to predict the molecular interactions between ingredients and target genes. Enrichment analysis was performed to explore the possible signal pathways. LeDock was used to simulate the interaction form between proteins and main active ingredients and to deduce key amino acid positions.

Results

Two hundred eighty-nine target genes and seventy-four pharmacological ingredients were obtained from public databases. Several key ingredients (quercetin, kaempferol, and stigmasterol) and primary core target genes (PTGS1, NCOA2, and PRSS1) were detected through ingredient-target gene network analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis demonstrated that ingredients affect networks mainly in nuclear receptor activity and G protein-coupled amine receptor activity; besides, fluid shear stress and atherosclerosis, human cytomegalovirus infection, and hepatitis B signaling pathways might be the principal therapy ways. A series of presumed key amino acid sites (189ASP, 190SER, 192GLN, 57HIS, and 99TYE) were calculated in PRSS1. Six of the target genes were differentially expressed between male and female patients.

Conclusions

Seven new putative target genes (ACHE, ADRA1A, AR, CHRM3, F7, GABRA1, and PRSS1) were observed in this work. Based on the result of GO and KEGG analysis, this work will be helpful to further demonstrate the molecular mechanism of PTEC treatment of IS.

Meta-Analysis of Factor V, Factor VII, Factor XII, and Factor XIII-A Gene Polymorphisms and Ischemic Stroke

Numerous studies examined the association between factors FV, FVII, FXII, and FXIII-A gene polymorphisms and ischemic stroke, but conclusive evidence is yet to be obtained. Thus, this meta-analysis aimed to investigate the novel association of FV rs1800595, FVII rs5742910, FXII rs1801020, and FXIII-A rs5982 and rs3024477 polymorphisms with ischemic stroke risk. A systematic review was performed on articles retrieved before June 2018. Relevant data were extracted from eligible studies and meta-analyzed using RevMan version 5.3. The strength of association between studied polymorphisms and ischemic stroke risk was calculated as odds ratios and 95% confidence intervals, by applying both fixed- and random-effect models. A total of 25 studies involving 6100 ischemic stroke patients and 9249 healthy controls were incorporated in the final meta-analysis model. Specifically, rs1800595, rs5742910, rs1801020, rs5982, and rs3024477 consisted of 673, 3668, 922, 433, and 404 cases, as well as 995, 4331, 1285, 1321, and 1317 controls, respectively. The pooled analysis indicated that there was no significant association of FV rs1800595, FVII rs5742910, FXII rs1801020, FXIII-A rs5982, and FXIII-A rs3024477 polymorphisms with ischemic stroke risk, under any genetic models (dominant, recessive, over-dominant, and allelic). The present meta-analysis concluded that FV rs1800595, FVII rs5742910, FXII rs1801020, and FXIII-A rs5982 and rs3024477 polymorphisms are not associated with ischemic stroke risk.

Coagulation factor VII gene polymorphisms are not associated with the occurrence or the survival of hepatocellular carcinoma: a report of 37 cases

Objective

: Coagulation factor VII (FVII) triggers the extrinsic pathway of blood coagulation. In our previous study, we showed that FVII plays an important role in tumorigenesis of hepatocellular carcinoma (HCC). However, the role of FVII polymorphism in HCC is still unknown. The present study aimed to investigate the relationship between HCC carcinogenesis and single nucleotide polymorphism of FVII.

Methods

: Thirty-seven HCC patients and 30 healthy donors were recruited in this study. Four common FVII gene polymorphisms - a decanucleotide insertion at position -323 (-323ins10-bp), a G to T substitution at position -401 (-401G/T), a G to A substitution at position -402 (-402G/A), and a T to C substitution at position -122 (-122T/C) - were analyzed by sequencing or commercialized assays using genomic DNA isolated from blood samples. Clinicopathological parameters between control and HCC subjects were compared according to the specific genotypes.

Results

: The most common nucleotide variation was -402G/A. However, no statistically significant difference was observed between healthy controls and HCC subjects for all four polymorphisms in terms of genotype distribution and allele frequencies, indicating that these polymorphisms may not affect HCC tumorigenesis. Furthermore, no association was found between -402G/A polymorphisms and tumor stage, recurrence, and overall survival.

Conclusions

: Our results indicate that FVII polymorphisms may not be a key factor that clinically impact tumorigenesis and outcomes of HCC, although further investigations should be conducted to confirm our findings.

Thrombophilia screening in young patients with cryptogenic stroke

The clinical relevance of thrombophilia screening in stroke patients is still a matter of debate, and descriptions of larger patterns of genetic variability are rare. We assessed the frequency of hereditary hypercoagulability in young patients with cryptogenic stroke (n = 44) and in healthy blood donors (n = 282) without prior cardiovascular event. Furthermore, we focused on the impact of thrombophilia screening on secondary stroke prevention. Results: Compared to the control group (19–67 years; median 38.5 years; 64% women), there was a lower prevalence of the FVII-R353Q mutation (p = 0.033) in stroke patients (17–52 years; median 36 years; 59.1% women). Of note, the FVII-R353Q mutation lowers FVII plasma levels, probably reducing the risk of cardiovascular events. The prevalence of the remaining 13 gene polymorphisms did not differ significantly. However, the prevalence of FV Leiden mutation tended to be higher among stroke patients. Conclusion: Overall, extended screening for inherited thrombophilia had an impact on medical stroke prevention in every sixth patient with cryptogenic stroke.

Low plasma FVII:C and activated FVII as predictive markers for overt disseminated intravascular coagulation

In sepsis, binding of factor VII (FVII:C) and activated factor VII (FVIIa) with tissue factor is the key step of coagulation resulting in disseminated intravascular coagulation (DIC). We conducted a prospective cohort study among 47 septic patients, aged 8 months to 18.8 years. They were initially divided into three groups of no DIC (n=27), non-overt DIC (n=14) and overt DIC (n=6). Blood samples were collected at 0, 24 and 48 hours (h) after the onset of sepsis. At the onset of sepsis, FVII:C tended to be lower in the non-overt DIC [median 57 % (interquartile range [IQR] 41-80)] and overt DIC groups [33 % (23-52)] than that in the no DIC group [65 % (44-87)]. Whereas FVIIa tended to be lower in the overt DIC group [1.29 % (0.50-4.19)] than those in the non-overt DIC [3.01 % (1.01-5.24)] and no DIC groups [2.49 % (1.14-3.13)]. At 24 h, FVII:C was significantly lower in the non-overt DIC [57 % (41-101)] and overt DIC groups [31 % (28-49)] than that in the no DIC group [83 % (70-102)]. While FVIIa was significantly lower in the overt DIC group [2.15 % (0.86-3.96)] than that in the no DIC group [3.83 % (2.90-5.46)]. Using FVII:C <65 % or FVIIa <3 % at 24 h among patients without hepatic dysfunction to determine overt DIC at 24 h, the sensitivity was 83.9 % and 77.4 %, respectively, and the specificity was both 83.3 %. Patients with low FVII:C and low FVIIa at 24 h after the onset of sepsis had a 20.8-fold (95 % confidence interval [CI], 2.0-213.0, p=0.010) and 14.4-fold (95 %CI, 1.5-142.4, p=0.023) chance of overt DIC.

Assessing Circulating Factor VIIa-Antithrombin Complexes in Acute Ischemic Stroke: A Pilot Study

AIM

The goal of this study was to determine the levels of factor VII (FVII), factor VIIa-antithrombin complexes (FVIIa-AT), total tissue factor (TF), and tissue factor-bearing microparticles (MPs-TF) in patients with acute ischemic stroke. Further, we sought evidence of an association between hemostatic markers, time of blood sampling, type of treatment, and patient outcomes.

METHODS

Venous blood samples were collected from 33 patients on the first day and on the seventh day after stroke diagnosis. Age-matched controls were also included (n = 20). Plasma levels of FVII, FVIIa-AT, total TF, and MPs-TF were measured by enzyme-linked immunosorbent assay. We divided patients into 2 groups: thrombolysis group (n = 13) and nonthrombolysis group (n = 20). Furthermore, evaluation of the National Institutes of Health Stroke Scale and the Barthel Index was performed on the first day and the seventh day.

RESULTS

Patients with ischemic stroke showed significantly lower plasma FVII, FVIIa-AT, and total TF levels than controls (median, 112.25% vs 132.05%, P = .004; 107.97 pmol/L vs 154.94 pmol/L, P < .001; 81.74 pg/mL vs 105.71 pg/mL, P < .001, respectively). In contrast, levels of plasma MPs-TF were significantly higher in patients with stroke compared to healthy controls (1.60 pg/mL vs 0.74 pg/mL, P < .001). Additionally, the thrombolysis group had lower FVII levels on the seventh day compared to the first day (median, 109.80% vs 115.74%, P = .04).

CONCLUSION

Factor VII, FVIIa-AT, and total TF are decreased, while MPs-TF are elevated in patients with ischemic stroke. We observed a slight but significant effect of alteplase on FVII plasma levels.

Molecular pathology of rare bleeding disorders (RBDs) in India: a systematic review

Background

Though rare in occurrence, patients with rare bleeding disorders (RBDs) are highly heterogeneous and may manifest with severe bleeding diathesis. Due to the high rate of consanguinity in many caste groups, these autosomal recessive bleeding disorders which are of rare occurrence in populations across the world, may not be as rare in India.

Objectives

To comprehensively analyze the frequency and nature of mutations in Indian patients with RBDs.

Methods

Pubmed search was used (www.pubmed.com) to explore the published literature from India on RBDs using the key words “rare bleeding disorders”, “mutations”, “India”, “fibrinogen”, “afibrinogenemia”, “factor II deficiency”, “prothrombin” “factor VII deficiency”, “factor V deficiency”, “factor X deficiency”, “factor XI deficiency”, “combined factor V and VIII deficiency”, “factor XIII deficiency”, “Bernard Soulier syndrome” and “Glanzmanns thrombasthenia” in different combinations. A total of 60 relevant articles could be retrieved. The distribution of mutations from India was compared with that of the world literature by referring to the Human Gene Mutation Database (HGMD) (www.hgmd.org).

Results

Taken together, 181 mutations in 270 patients with different RBDs have been reported from India. Though the types of mutations reported from India and their percentage distribution with respect to the world data are largely similar, yet much higher percentage of small deletions, duplication mutations, insertions, indels were observed in this analysis. Besides the identification of novel mutations and polymorphisms, several common mutations have also been reported, which will allow to develop a strategy for mutation screening in Indian patients with RBDs.

Conclusion

There is a need for a consortium of Institutions working on the molecular pathology of RBDs in India. This will facilitate a quicker and cheaper diagnosis of RBDs besides its utility in first trimester prenatal diagnosis of the affected families.

[Update on the genetics of stroke]

Stroke is a disease with significant morbidity, mortality, and economic and social impacts. It is a complex entity whose pathogenesis involves multiple environmental and genetic factors, with the latter having a role in up to 50% of strokes. The objective of the review is to analyze the available methods for the genetic diagnosis including linkage studies of variation in copy number, gene - candidate approximations, or whole genome (GWAS) and polymorphisms associated with its pathogenesis. We describe several single nucleotide polymorphisms (SNPs) associated with stroke in association studies and GWAS such as SNPs of angiotensin, the aldosterone system, paraoxonases, nitric oxide, coagulation, and fibrinolysis system, among others. We also analyze the role of certain polymorphisms in the phenotype of the carotid plaque, intracranial aneurysms and lobar hemorrhages. Pharmacogenomic aspects in which SNPs affect the response and safety regarding the use of different drugs are also described. Several SNPs that significantly contribute to the risk of stroke are also described. The advent of techniques like GWAS has contributed to the understanding of genetics and pharmacogenomics of stroke.

Pathogenetic role of Factor VII deficiency and thrombosis in cross-reactive material positive patients

Congenital Factor VII (FVII) deficiency can be divided into two groups: cases of "true" deficiency, or cross-reactive material (CRM) negative and variants that are cross-reactive material positive.The first form is commonly recognized as Type I condition whereas the second one is known as Type II. FVII deficiency has been occasionally associated with thrombotic events, mainly venous. The reasons underlying this peculiar manifestation are unknown even though in the majority of associated patients thrombotic risk factors are present. The purpose of the present study was to investigate if a thrombotic event was more frequent in Type I or in Type II defect.The majority of patients with FVII deficiency and thrombosis belong to Type II defects. In the following paper we discuss the possible role of the dysfunctional FVII cross-reaction material as a contributory cause for the occurrence of thrombosis.

Decanucleotide insertion polymorphism of F7 significantly influences the risk of thrombosis in patients with essential thrombocythemia

OBJECTIVE

There is strong evidence that certain thrombophilic single nucleotide polymorphisms (SNPs) account for an increased risk of thrombosis. The additive impact of inherited thrombotic risk factors to a certain disease- immanent thrombotic risk is vastly unknown. Therefore, we aimed to investigate the influence of three novel, preselected SNPs on the risk of thrombosis in patients diagnosed with myeloproliferative neoplasm (MPN).

METHOD

In 167 patients with a diagnosis of essential thrombocythemia (ET) or prefibrotic primary myelofibrosis (PMF) thrombophilic SNPs in the genes of factor VII (F7), nitric oxide synthase 3 (NOS3) and FcɣRIIa (FCGR2A) were determined. Subsequently, the polymorphic variants were correlated with the incidence of major thrombosis after diagnosis.

RESULTS

Decanucleotide insertion polymorphism of F7 emerged as an independent, significant risk factor for total thrombosis and arterial thrombosis in particular in the whole group of patients (P = 0.0007) as well as in the separate analysis of patients with ET (P = 0.0002).

CONCLUSION

Our results illustrate that the risk of thrombosis in MPN is significantly multiplied by inherited thrombophilic SNPs. This result points to the importance of a combined consideration of the inherited and the acquired hypercoagulable state in patients with MPN. Larger studies are needed to confirm and extend these important findings.