Plasminogen activator inhibitor type 1 gene polymorphisms and haplotypes are associated with plasma plasminogen activator inhibitor type 1 levels but not with myocardial infarction or stroke

Identification of genomic loci regulating platelet plasminogen activator inhibitor-1 in mice

BACKGROUND

Plasminogen activator inhibitor-1 (PAI-1, Serpine1) is an important circulating fibrinolysis inhibitor. PAI-1 exists in 2 pools, packaged within platelet α-granules and freely circulating in plasma. Elevated plasma PAI-1 levels are associated with cardiovascular disease. However, little is known about the regulation of platelet PAI-1 (pPAI-1).

OBJECTIVES

We investigated the genetic control of pPAI-1 levels in mice and humans.

METHODS

We measured pPAI-1 antigen levels via enzyme-linked immunosorbent assay in platelets isolated from 10 inbred mouse strains, including LEWES/EiJ (LEWES) and C57BL/6J (B6). LEWES and B6 were crossed to produce the F1 generation, B6LEWESF1. B6LEWESF1 mice were intercrossed to produce B6LEWESF2 mice. These mice were subjected to genome-wide genetic marker genotyping followed by quantitative trait locus analysis to identify pPAI-1 regulatory loci.

RESULTS

We identified differences in pPAI-1 between several laboratory strains, with LEWES having pPAI-1 levels more than 10-fold higher than those in B6. Quantitative trait locus analysis of B6LEWESF2 offspring identified a major pPAI-1 regulatory locus on chromosome 5 from 136.1 to 137.6 Mb (logarithm of the odds score, 16.2). Significant pPAI-1 modifier loci on chromosomes 6 and 13 were also identified.

CONCLUSION

Identification of pPAI-1 genomic regulatory elements provides insights into platelet/megakaryocyte-specific and cell type-specific gene expression. This information can be used to design more precise therapeutic targets for diseases where PAI-1 plays a role.

Clinical impact of the PAI-1 4G/5G polymorphism in Chinese patients with venous thromboembolism

Background

Venous thromboembolism (VTE) is a life-threatening cardiovascular syndrome that characterized by the imbalance of hemostasis and thrombosis and the formation of thrombi in the blood vessels. The aim of this study was to elucidate the clinical impact of the PAI-1 4G/5G polymorphism in Chinese patients with VTE.

Methods

A total of 169 subjects (89 VTE, 10 hyperbilirubinemia, 10 hyperlipidemia and 60 healthy controls) were recruited at Peking Union Medical College Hospital. The accuracy of the TaqMan-MGB RT-PCR method for detecting F5 G1691A (FVL) and PAI-1 4G/5G polymorphisms was evaluated by using sequencing method as the gold standard. Besides, the association of the PAI-1 4G/5G polymorphism with susceptibility, treatment efficacy and recurrence status of VTE in Chinese population were explored. Eventually, the plasma PAI-1 antigen levels and PAI-1 4G/5G polymorphisms were determined on additional 64 subjects (32 VTE and 32 healthy controls) simultaneously.

Results

The TaqMan-MGB RT-PCR method was proven to be highly accurate in determining the FVL and PAI-1 4G/5G polymorphisms without interference from bilirubin and lipids in the samples. No obvious correlation of the PAI-1 4G/5G polymorphism with VTE was observed in our study by using five genetic models (allele, genotype, dominant, recessive and additive). Additionally, we also observed that individuals with the 4G/5G genotype had lower neutrophil counts and neutrophil-to-lymphocyte ratio (NLR) than the 5G/5G genotype. Furthermore, we found that the patients with the 5G/5G genotype were more likely to achieve complete recanalization compared to the 4G/4G genotype. In addition, individuals carrying the 5G/5G genotype were more likely to develop a recurrence-free status as compared to individuals with the 4G/4G or 4G/5G genotypes. PAI-1 antigen levels in the VTE group were significantly higher than those in the HC group. However, there was no significant difference in the antigen levels of PAI-1 among subjects carrying various genotypes in the VTE group or HC group.

Conclusion

The PAI-1 4G/5G polymorphism has potential value in assessing the prognosis of Chinese patients with VTE. Our study has laid the foundation for the application of PAI-1 4G/5G polymorphism in the personalized management and monitoring of patients with VTE.

The Intrinsically Disordered Loop in the USF1 bHLHZ Domain Modulates Its DNA-Binding Sequence Specificity in Hereditary Asthma

USF1, a basic region/helix-loop-helix/leucine zipper (bHLHZ) transcription factor, binds to the E-box in the PAI-1 (plasminogen activator inhibitor) promoter. Two alleles containing the E-box control PAI-1 transcription; these alleles are termed "4G" and "5G" based on the G tract flanking E-box. USF1-governed transcription of PAI-1 is elevated in heritable asthma sufferers: the 4G/4G genotype has the highest plasma levels of PAI-1. While USF1 uses its basic region to bind E-box, we found that it uses its 12 amino-acid loop to recognize the flanking sequence and discern the single-nucleotide difference between the alleles. We used the bacterial one-hybrid and electrophoretic mobility shift assays to assess protein-DNA recognition, and circular dichroism to examine protein secondary structure. We mutated Ser233 and Thr234 in the USF1 bHLHZ loop to Ala to generate S233A and T234A. Interestingly, USF1 bHLHZ, S233A, and T234A prefer the 5G sequence (USF1 bHLHZ K_d values 4.1 ± 0.3 nM and 7.0 ± 0.4 nM for 5G and 4G, respectively), whereas studies in stimulated human mast cells showed a preference for 4G. We replaced the 8 amino-acid loop of transcription factor Max bHLHZ with the 12 amino-acid USF1 loop: this mutant now distinguishes the 4G/5G polymorphism-while Max bHLHZ does not-confirming that USF1 differentiation of the 4G/5G is driven by the loop.

Atherosclerotic and thrombotic genetic and environmental determinants in Egyptian coronary artery disease patients: a pilot study

BACKGROUND

Coronary artery disease (CAD) is the leading cause of morbidity and mortality worldwide. Multiple genetic variants in combination with various environmental risk factors have been implicated. This study aimed to investigate the association of twelve thrombotic and atherosclerotic gene variants in combination with other environmental risk factors with CAD risk in a preliminary sample of Egyptian CAD patients.

METHODS

Twenty three consecutive CAD patients undergoing diagnostic coronary angiography and 34 unrelated controls, have been enrolled in the study. Genotyping was based on polymerase chain reaction and reverse multiplex hybridization. Five genetic association models were tested. Data distribution and variance homogeneity have been checked by Shapiro-Wilk test and Levene test, respectively; then the appropriate comparison test was applied. Spearman's rank correlation coefficient was used for correlation analysis and logistic regression has been performed to adjust for significant risk factors. Clustering the study participants according to gene-gene and gene-environment interaction has been done by Detrended Correspondence Analysis (DCA).

RESULTS

The univariate analysis indicated that the five variants; rs1800595 (FVR2; factor 5), rs1801133 (MTHFR; 5,10-methylenetetrahydrofolate reductase), rs5918 (HPA-1; human platelet antigen 1), rs1799752 (ACE; angiotensin-converting enzyme), and rs7412 and rs429358 (ApoE; apolipoprotein E) were significantly associated with CAD susceptibility under different genetic models. Multivariate analysis revealed clustering of the study population into three patient groups (P) and one control group. FVR2 was the most variant associated with CAD patients, combined with the factor V Leiden (FVL) variant in P1 cluster and with both ACE and MTHFR 667C > T in P2. Whereas, P3 was mostly affected by both MTHFR 667C > T and FXIII (factor 13) V89L mutations. When combined with traditional risk factors, P1 was mostly affected by dyslipidemia, smoking and hypertension, while P2 was mostly affected by their fasting blood sugar levels and ApoE variant.

CONCLUSIONS

Taken together, these preliminary results could have predictive value to be applied in refining a risk profile for our CAD patients, in order to implement early preventive interventions including specific antithrombotic therapy. Further large scale and follow-up studies are highly recommended to confirm the study findings.

Association of G894T eNOS, 4G/5G PAI and T1131C APOA5 polymorphisms with susceptibility to myocardial infarction in Morocco

Background

Myocardial infarction (MI) is a common multifactorial disease. Numerous studies have found that genetic plays an essential role in MI occurrence. The main objective of our case–control study is to explore the association of G894T eNOS (rs1799983), 4G/5G PAI (rs1799889) and T1131C APOA5 (rs662799) polymorphisms with MI susceptibility in the Moroccan population.

Methods and results

118 MI patients were recruited vs 184 healthy controls. DNA samples were genotyped by PCR-RFLP method using MboI, BslI and MseI restriction enzymes respectively for the G894T eNOS, 4G/5G PAI and T1131C APOA5 polymorphisms. Our results show that the G894T eNOS was significantly associated with increased risk of MI under the three genetic transmission models (dominant: OR = 1.64, 95% CI = 1.05–2.58, P = 0.003; recessive: OR = 2.15, 95% CI = 0.74–6.16, P = 0.03; additive: OR = 1.54, 95% CI = 1.06–2.23, P = 0.001). The T1131C APOA5 polymorphism was associated to MI risk in recessive and additive models (OR = 1.53, 95% CI = 0.72–3.2, P = 0.04 and OR = 1.78, 95% CI = 1.26–2.51, P = 0.03 respectively). For the 4G/5G PAI variant, even the cases and controls groups were not in Hardy–Weinberg Equilibrium (HWE), the dominant and additive models show a statistically significant association with MI risk (OR = 7.96, 95%CI = 3.83–16.36, P = 0.01 and OR = 1.96, 95% CI = 1.4–2.72, P = 0.03 respectively).

Conclusion

Our results suggest that G894T eNOS and T1131C APOA5 polymorphisms may be considered as genetic markers of MI among the Moroccan population. Further studies including larger sample sizes and exploring more genetic associations are needed to confirm our results and to better understand the susceptibility to MI.

GLU298ASP and 4G/5G Polymorphisms and the Risk of Ischemic Stroke in Young Individuals

BACKGROUND

Polymorphisms in the endothelial nitric oxide synthase (eNOS) and in the plasminogen activator inhibitor -1 (PAI-1) genes have been implicated in stroke pathogenesis but results are still controversial. The aim of this study was to examine the possible contribution of Glu298Asp in the eNOS and 4G/5G in the PAI-1polymorphisms with ischemic stroke in a young Mexican population.

MATERIALS AND METHODS

In a case-control study, conducted between January 2006 and June 2010, 204 patients ≤45 years of age with ischemic stroke and 204 controls matched by age and gender, were recruited. The Glu298Asp and 4G/5G polymorphisms were determined in all participants by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

There was a significant difference in the Glu298Asp genotype distribution (P=0.001) and allele frequency between the two groups (P=0.001). The 4G/5G genotype distribution (P=0.40) and the allele frequency was similar between groups; (P=0.13). There were independent factors for ischemic stroke: Asp carriage (GluAsp+AspAsp) (P=0.02); smoking (P=0.01); hypertension (P=0.03), and familial history of atherothrombotic disease (P=0.04).

CONCLUSIONS

The Asp allele from the Gu298Asp gene represents an independent risk factor for ischemic stroke in a young Mexican population. In contrast, the 4G/5G was not associated with an increased risk for this disease in the same group of patients, as previously has been demonstrated in other populations.

Genetics of ischaemic stroke in young adults

Background

Stroke may be a clinical expression of several inherited disorders in humans. Recognition of the underlined genetic disorders causing stroke is important for a correct diagnosis, for genetic counselling and, even if rarely, for a correct therapeutic management. Moreover, the genetics of complex diseases such the stroke, in which multiple genes interact with environmental risk factors to increase risk, has been revolutionized by the Genome-Wide Association Study (GWAS) approach.

Scope of review

Here we review the single-gene causes of ischemic stroke, bringing the reader from the candidate gene method toward the exciting new horizons of genetic technology.

Major conclusions

The aetiological diagnosis of ischemic stroke in young adults is more complex than in the elderly. The identification of a genetic cause is important to provide appropriate counseling and to start a correct therapy, when available. The advent of GWAS technology, such as for other complex pathological conditions, has contributed enormously to the understanding of many of these genetic bases. For success large, well phenotyped case cohorts are required, and international collaborations are essential.

General significance

This review focuses on the main causes of genetically-based ischemic stroke in young adults, often classified as indeterminate, investigating also the recent findings of the GWAS, in order to improve diagnostic and therapeutic management.

•

The aetiological diagnosis of stroke in young adults needs a different and more complex diagnostic work up than in older adults.

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Stroke may be a clinical expression of several inherited disorders in humans.

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The most common genetic causes of stroke are CADASIL, Fabry and mitochondrial diseases.

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Recognition of the underlined genetic disorders causing stroke is important for the correct management of the patient.

Global fibrinolytic activity, PAI-1 level, and 4G/5G polymorphism in Thai children with arterial ischemic stroke

BACKGROUND

Prolonged euglobulin clot lysis time (ECLT) and increased level of plasminogen activator inhibitor-1 (PAI-1) were reported to be risk factors of arterial ischemic stroke (AIS) by some studies; however, these findings were not supported by other studies. The objective of this study was to determine the association of ECLT, PAI-1 level, and polymorphisms of 4G and 5G of PAI-1 gene to the development of AIS in Thai children.

METHODS

This study included patients aged 1-18 years old. Diagnosis of AIS was confirmed by imaging study. The control group was age- and sex-matched healthy subjects. Demographic data were recorded, and blood was tested for ECLT, PAI-1 level, lipid profiles, fasting blood sugar (FBS), and 4G and 5G polymorphisms of PAI-1 gene.

RESULTS

There were 70 subjects participating in this study, consisting of 30 patients and 40 controls. Demographic data, lipid profiles, and FBS were similar between the 2 groups. Furthermore, ECLT and PAI-1 level did not differ between patient and control groups; however, both showed significant correlation (r = .352, P = .006). The 4G/5G polymorphism was the most common genotype in both patient and control groups (69.0% vs. 80.0%). However, 4G and 5G polymorphisms of PAI-1 gene did not correlate with PAI-1 level in this study (P = .797).

CONCLUSIONS

The PAI-1 level and 4G/5G polymorphism may not be a risk factor of AIS in this population. It was also found that the 4G/5G polymorphism was the most common PAI-1 genotype in this study.

The study of t-PA, u-PA and PAI-1 genes polymorphisms in patients with abdominal aortic aneurysm

The most important feature of abdominal aortic aneurysm (AAA) pathogenesis is an enzymatic degradation of elastic lamellae and extracellular matrix proteins particularly with participation of matrix metalloproteinases. Plasmin, which is responsible for the dissolution of fibrin in blood vessels, plays also a key role in the cascade for activation of the metalloproteinases. The purpose of this study was to evaluate the influence of selected polymorphisms in genes coding for tissue plasminogen activator (−7351 C/T polymorphism), urokinase-type plasminogen activator (1788 C/T polymorphism) and plasminogen activator inhibitor 1 (−675 4G/5G and −844 G/A polymorphism) on the susceptibility to AAA. We performed a case–control study of 153 polish patients hospitalized due to AAA and compared them with matched healthy control subjects. The polymorphisms were ascertained through genotyping by polymerase chain reaction and restriction digestion of amplified fragments or through high-resolution melting analysis. In this study we have found lower frequency of wild-type GG genotype of the −844G/A PAI-1 polymorphism in cases than in controls, what may suggest the protective effect of this genotype for the risk of AAA development. None of the remaining polymorphisms tested were associated with AAA occurrence.

Interaction between air pollution exposure and genes in relation to levels of inflammatory markers and risk of myocardial infarction

OBJECTIVES

Air pollution exposure induces cardiovascular effects, possibly via systemic inflammation and coagulation misbalance. Genetic variation may determine individual susceptibility. Our aim was to investigate effect modification by inflammation (Interleukin6 (IL6), tumour necrosis factor-α (TNF-α)) and coagulation (fibrinogen Bβ, plasminogen activator inhibitor-1 (PAI-1)) gene variants on the effect of long-term or short-term air pollution exposure on both blood marker levels and non-fatal myocardial infarction (MI) risk.

DESIGN

Population-based case-control study with a nested case-crossover study. Gene-environment interactions for short-term and long-term air pollution on blood marker levels were studied in population controls, for long-term exposure on MI risk using case-control design, and for short-term exposure on MI onset using case-crossover design.

SETTING

The Stockholm Heart Epidemiology Programme (SHEEP) conducted in 1992-1994 in Stockholm, Sweden. Spatial modelling was used to assess long-term (up to 30 years retrospectively) air pollution exposure to traffic-NO2 and heating-SO2 emissions at home addresses. Urban background NO2, SO2, PM10 and O3 measurements were used to estimate short-term (up to 5 days) air pollution exposure.

PARTICIPANTS

1192 MI cases and 1506 population controls aged 45-70 years.

OUTCOMES

The levels of blood markers of inflammation (IL-6, TNF-α) and coagulation (fibrinogen, PAI-1) and MI risk.

RESULTS

We observed gene-environment interaction for several IL6 and TNF SNPs in relation to inflammation blood marker levels. One-year traffic-NO2 exposure was associated with higher IL-6 levels with each additional IL6-174C allele, and 1-year heating-SO2 exposure with higher levels of TNF-α in TNF-308AA homozygotes versus -308G carriers. Short-term air pollution exposure also interacted with IL6 and TNF in relation to marker levels. The risk of MI followed the effect on blood markers in each genotype group.

CONCLUSIONS

Genetic variants in IL6 and TNF may modify effects of long-term and short-term air pollution exposure on inflammatory marker levels and MI risk.

The 4G/4G genotype of the PAI-1 (serpine-1) 4G/5G polymorphism is associated with decreased lung allograft utilization

Widespread thrombi are found among donor lungs rejected for transplantation. The 4G/5G polymorphism in the plasminogen activator inhibitor (PAI-1) gene impacts transcription and the 4G allele is associated with increased PAI-1 levels. We hypothesized that the 4G/4G genotype would be associated with decreased lung graft utilization, potentially because of worse oxygenation in the donor. We genotyped donors managed by the California Transplant Donor Network from 2001 to 2008 for the 4G/5G polymorphism in the PAI-1 gene. Non-Hispanic donors from 2001 to 2005 defined the discovery cohort (n = 519), whereas donors from 2006 to 2008 defined the validation cohort (n = 369). We found, that the odds of successful lung utilization among Non-Hispanic white donors were lower among donors with the 4G/4G genotype compared to those without this genotype in both the discovery (OR = 0.55, 95% CI = 0.3-0.9, p = 0.02) and validation (OR = 0.5, 95% CI = 0.3-0.9, p = 0.03) cohorts. This relationship was independent of age, gender, cause of death, drug use and history of smoking. Donors with the 4G/4G genotype also had a lower PaO2/FiO2 ratio (p = 0.03) and fewer donors with the 4G/4G genotype achieved the threshold PaO2/FiO2 ratio ≥ 300 (p = 0.05). These findings suggest a role for impaired fibrinolysis resulting in worse gas exchange and decreased donor utilization.

Effects of altered plasminogen activator inhibitor-1 expression on cardiovascular disease

Plasminogen Activator Inhibitor-1 (PAI-1) is a multifunctional protein with the ability to not only regulate fibrinolysis through inhibition of plasminogen activation, but also cell signaling events which have direct downstream effects on cell function. Elevated plasma levels of this protein have been shown to have profound effects on the development and progression of cardiovascular diseases. However, results from a number of studies, especially those using PAI-1 deficient mouse models, have demonstrated that its function is ambiguous, with evidence of both preventing and enhancing various disease states. A number of lifestyle changes and pharmacological reagents have been identified that can regulate PAI-1 levels or function. Those reagents that target function are focused on its ability to regulate plasmin formation, and have been studied in in vivo models of thrombosis. Further investigations involving regulation of cell function could potentially resolve paradoxical issues associated with the function of this protein in regulating cardiovascular disease.

Systolic blood pressure and incident heart failure in the elderly. The Cardiovascular Health Study and the Health, Ageing and Body Composition Study

BACKGROUND

The exact form of the association between systolic blood pressure (SBP) and heart failure (HF) risk in the elderly remains incompletely defined, especially in individuals not receiving antihypertensive drugs.

OBJECTIVE

To examine the association between SBP and HF risk in the elderly.

DESIGN

Competing-risks proportional hazards modelling of incident HF risk, using 10-year follow-up data from two NIH-sponsored cohort studies: the Cardiovascular Health Study (inception: 1989-90 and 1992-3) and the Health ABC Study (inception: 1997-8).

SETTING

Community-based cohorts.

PARTICIPANTS

4408 participants (age, 72.8 (4.9) years; 53.1% women, 81.7% white; 18.3% black) without prevalent HF and not receiving antihypertensive drugs at baseline.

MAIN OUTCOME MEASURES

Incident HF, defined as first adjudicated hospitalisation for HF.

RESULTS

Over 10 years, 493 (11.2%) participants developed HF. Prehypertension (120-139 mm Hg), stage 1 (140-159 mm Hg), and stage 2 (≥160 mm Hg) hypertension were associated with escalating HF risk; HRs versus optimal SBP (<120 mm Hg) in competing-risks models controlling for clinical characteristics were 1.63 (95% CI 1.23 to 2.16; p=0.001), 2.21 (95% CI 1.65 to 2.96; p<0.001) and 2.60 (95% CI 1.85 to 3.64; p<0.001), respectively. Overall 255/493 (51.7%) HF events occurred in participants with SBP <140 mm Hg at baseline. Increasing SBP was associated with higher HF risk in women than in men; no race-SBP interaction was seen. In analyses with continuous SBP, HF risk had a continuous positive association with SBP to levels as low as 113 mm Hg in men and 112 mm Hg in women.

CONCLUSIONS

There is a continuous positive association between SBP and HF risk in the elderly for levels of SBP as low as <115 mm Hg; over half of incident HF events occur in individuals with SBP <140 mm Hg.

Sequence variations in the FII, FV, F13A1, FGB and PAI-1 genes are associated with differences in myocardial perfusion

AIMS

Coronary artery disease (CAD) is a significant cause of morbidity and mortality in modern societies. The association between genetic markers and CAD is still poorly understood. In this study, we evaluated the effect of five genetic variants: Factor V Leiden (FV:c.1691G>A) (rs6025), Factor II prothrombin (FII:c.20210G>A; rs1799963), plasminogen activator inhibitor 1 (PAI-1) -675(4G/5G; SERPINE1:g.4329_4330insG; rs34857375), β-fibrinogen -455G>A (FGB:c.4577G>A; rs1800790) and Factor XIII (F13A1:c.103G>T; rs5985) on myocardial perfusion.

MATERIALS & METHODS

We examined 523 patients using exercise-rest myocardial perfusion single photon emission computed tomography, where the summed stress score (SSS), summed rest score and summed difference score (SDS) indexes, were calculated. In order to examine the independent prognostic ability of genotype on SSS and SDS, multiple linear regression models were used.

RESULTS

It was found that Factor V Leiden, Factor XIII, β-fibrinogen and PAI-1 genotypes were independent prognostic predictors of SSS and SDS with Factor XIII exhibiting the strongest association. Moreover, Factor II prothrombin proved an independent prognostic predictor of SSS.

CONCLUSION

Our study provides the first evidence of an association between these polymorphisms and myocardial perfusion, suggesting that the process of coronary artery disease and also patients' prognosis, may be modified by the FV:c.1691G>A, FII:c.20210G>A, PAI-1 -675 (4G/5G), β-fibrinogen FGB:c.4577G>A and F13A1:c.103G>T genotypes.

Increased serum vWF and sVCAM-1 levels are associated with late or very late angiographic stent thrombosis after sirolimus-eluting stent implantation

BACKGROUND

This study sought to examine whether circulatory levels of endothelial dysfunction biomarkers [vascular cell adhesion molecule (sVCAM-1), intercellular adhesion molecule (sICAM-1), sE-selectin, von Willebrand factor (vWF), tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1)] are associated with occurrence of late or very late stent thrombosis (ST) after percutaneous coronary intervention with sirolimus-eluting stent implantation, and to assess the possible influence of genetic variants of these proteins on ST.

METHODS

Serum levels of sVCAM-1, sICAM-1, sE-selectin, vWF, t-PA and PAI-1 were measured, and polymorphisms of vWF (-1234C/T, -1185A/G and -1051G/A), t-PA (insertion/deletion) and PAI-1 genes (4G/5G) were determined in 41 patients who experienced at least one episode of late or very late ST. Eighty-two patients without ST randomly selected from the same study period served as controls.

RESULTS

Serum levels of vWF, sVCAM-1 and sICAM-1 were significantly increased in patients with ST than in controls (all P<0.01). No significant difference was observed in the genotype and allele distribution of the vWF, t-PA and PAI-1 gene polymorphisms. Multivariable logistic regression analysis showed that vWF, sVCAM-1, discontinuation of clopidogrel therapy and left ventricular ejection fraction of less than 50% were independent determinants of late ST.

CONCLUSION

Increased serum vWF and sVCAM-1 levels are associated with late ST, suggesting that endothelial dysfunction contributes to the development of late or very late ST.

Plasminogen activator inhibitor type-1 gene 4G/5G polymorphism is associated with hypertensive patients in the Turkish population

This study has been performed on hypertensive patients in the Turkish population to determine the frequency of 4G/5G polymorphism genotypes of plasminogen activator inhibitor type-1 gene and with the aim of examining the role of this polymorphism in hypertension development. Genomic DNA obtained from 284 persons (176 patients with hypertension and 108 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using 4G and 5G allele-specific primers. Polymerase chain reaction products were assessed by being exposed to 2% agarose gel electrophoresis. Results were evaluated with the chi-square test. The 4G allele frequency was 31.25% and the 5G allele frequency was 68.75% in patients, whereas it was 49/51% in a control group. 5G5G genotype was found statistically high (p < 0.001) in patients relative to controls. This study showed that the plasminogen activator inhibitor type-1 gene 4G/5G polymorphism and the 5G5G genotype appear to be associated with an elevated risk of developing hypertension in a representative sample of Turkish population.

Prognostic value of plasma fibrinolysis activation markers in cardiovascular disease

The pivotal role of hypoactive endogenous fibrinolysis in the occurrence of thrombotic cardiovascular events is now well-recognized. To evaluate the diagnostic and prognostic role of impaired fibrinolysis, plasma fibrinolysis markers have been investigated in large prospective studies in both healthy individuals and patients with established coronary disease. Antigen and activity levels of components of the fibrinolytic system were measured by immunoassays, which replaced earlier global fibrinolysis tests. This review covers 45 studies in nearly 50,000 subjects, examining the association between plasma markers of fibrinolysis and coronary artery disease, to establish the usefulness of these markers in predicting future cardiovascular events. The predictive value of plasma levels of tissue-type plasminogen activator, platelet activator inhibitor-1, plasmin-antiplasmin complex, D-dimer, thrombin activatable fibrinolysis inhibitor, and lipoprotein(a) for major adverse cardiac events is highly variable and conflicting, especially after adjusting for conventional risk factors, judging from the published data in the last decade. The value of fibrinolysis activity markers is very limited in aiding diagnosis and risk stratification in the individual patient, on the basis of the weak prognostic values obtained in some studies and the lack of power in others. The physiological limitations of such markers in reflecting endogenous fibrinolysis is discussed. The emerging novel global assays of fibrinolysis will require large-scale clinical trials before their prognostic power or superiority to multiple biomarker measurements can be evaluated.

A-G-4G haplotype of PAI-1 gene polymorphisms -844 G/A, HindIII G/C, and -675 4G/5G is associated with increased risk of ischemic stroke caused by small vessel disease

BACKGROUND

Plasminogen activator inhibitor type 1 (PAI-1) is the major inhibitor of fibrinolysis. It was reported that PAI-1 gene polymorphisms affected PAI-1 level and might therefore influence the risk of vascular diseases, including stroke. We studied the association of three common polymorphisms in PAI-1 gene (-844 G/A, -675 4G/5G, and HindIII G/C) with the odds of different causes of ischemic stroke.

METHODS

We studied 390 patients with ischemic stroke due to large vessel disease (n = 117), small vessel disease (n = 121), and cardioembolism (n = 152) as well as 291 controls. The etiology of ischemic stroke was established using TOAST criteria. PAI-1 polymorphisms were genotyped with restriction fragment length polymorphism and single strand conformation polymorphism method.

RESULTS

A-G-4G haplotype of PAI-1 gene was found more frequently in stroke patients with small vessel disease than in control subjects (44.9% vs 35.7%; P = 0.02). No association was found between investigated genotype or allele frequencies and distinct causes of ischemic stroke.

CONCLUSIONS

Our results demonstrate that A-G-4G PAI-1 gene haplotype is associated with increased risk of small vessel disease stroke, but this study does not support an association of -844 G/A, -675 4G/5G, and HindIII G/C PAI-1 gene polymorphisms with particular etiology of ischemic stroke.

Association of the plasminogen activator inhibitor-1 gene 4G/5G polymorphism with ST elevation acute myocardial infarction in young patients

INTRODUCTION AND OBJECTIVES

To investigate the role of the 4G/5G polymorphism in the plasminogen activator inhibitor-1 (PAI-1) gene in patients with ST-elevation myocardial infarction (STEMI) aged < or =45 years and its influence on regulation of the plasma PAI-1 concentration.

METHODS

This case-control study included 127 consecutive patients aged < or =45 years with a diagnosis of STEMI who were admitted to a cardiovascular intensive care unit and 127 controls recruited between January 2006 and March 2007. Participants were genotyped for the 4G/5G polymorphism using the polymerase chain reaction and restriction fragment length polymorphism analysis, and their plasma PAI-1 concentrations were measured. Informed consent was obtained from all participants.

RESULTS

There was a significant difference in genotype distribution between the two groups (P< .002). The 4G allele occurred more frequently in the patient group (P=.032). In addition, there were significant independent associations between STEMI and the 4G allele (i.e., 4G/4G plus 4G/5G; odds ratio [OR]=2.29; 95% confidence interval [CI], 1.12-4.68; P=.022), smoking (OR=23.23; 95% CI, 8.92-60.47; P< .001), a family history of cardiovascular disease (OR=4.66; 95% CI, 2.06-10.52; P=.001) and hypertension (OR=5.42; 95% CI, 1.67-17.56; P=.005). The plasma PAI-1 concentration was higher in individuals who were homozygous for the 4G allele (P< .001).

CONCLUSIONS

The study findings indicate that the 4G allele is an independent risk factor for acute myocardial infarction in young patients, as are smoking, hypertension and a family history of inherited cardiovascular disease.

Plasminogen activator inhibitor-1 and asthma: role in the pathogenesis and molecular regulation

Plasminogen activator inhibitor (PAI)-1 is a major inhibitor of the fibrinolytic system. PAI-1 levels are markedly increased in asthmatic airways, and mast cells (MCs), a pivotal cell type in the pathogenesis of asthma, are one of the main sources of PAI-1 production. Recent studies suggest that PAI-1 may promote the development of asthma by regulating airway remodelling, airway hyperresponsiveness (AHR), and allergic inflammation. The single guanosine nucleotide deletion/insertion polymorphism (4G/5G) at -675 bp of the PAI-1 gene is the major genetic determinant of PAI-1 expression. Plasma PAI-1 level is higher in people with the 4G/4G genotype than in those with the 5G/5G genotype. A strong association between the 4G/5G polymorphism and the risk and the severity of asthma has been suggested. Levels of plasma IgE and PAI-1 and severity of AHR are greater in asthmatic patients with the 4G/4G genotype than in those with the 5G/5G genotype. The PAI-1 promoter with the 4G allele renders higher transcription activity than the PAI-1 promoter with the 5G allele in stimulated MCs. The molecular mechanism for the 4G allele-mediated higher PAI-1 expression is associated with greater binding of upstream stimulatory factor-1 to the E-box adjacent to the 4G site (E-4G) than to the E-5G. In summary, PAI-1 may play an important role in the pathogenesis of asthma. Further studies evaluating the mechanisms of PAI-1 action and regulation may lead to the development of a novel prognostic factor and therapeutic target for the treatment and prevention of asthma and other PAI-1-associated diseases.

Association between inflammatory components and physical function in the health, aging, and body composition study: a principal component analysis approach

BACKGROUND

In older adults, studies demonstrate an inverse relationship between physical function and individual inflammatory biomarkers. Given that the inflammatory response is a complex system, a combination of biomarkers may increase the strength and consistency of these associations. This study uses principal component analysis to identify inflammatory "component(s)" and evaluates associations between the identified component(s) and measures of physical function.

METHODS

Principal component analysis with a varimax rotation was used to identify two components from eight inflammatory biomarkers measured in 1,269 older persons. The study sample is a subset of the Health, Aging, and Body Composition study.

RESULTS

The two components explained 56% of the total variance in the data (34%, component 1 and 22%, component 2). Five markers (tumor necrosis factor-alpha [TNF-alpha], sTNFRI, sTNFRII, interleukin [IL]-6sR, IL-2sR) loaded highest on the first component (TNF-alpha related), whereas three markers (C-reactive protein [CRP], IL-6, plasminogen activator inhibitor-1) loaded highest on the second component (CRP related). After adjusting for age, sex, race, site, sampling indicator, total lean and fat mass, physical activity, smoking, and anti-inflammatory drug use, knee strength and a physical performance battery score were inversely related to the TNF-alpha-related component, but not to the CRP-related component (knee strength: betaTNFalpha = -2.71, p = .002; betaCRP = -0.88, p = .325; physical performance battery score: betaTNFalpha = -0.05, p < .001; betaCRP = -0.02, p = .171). Both components were positively associated with 400-m walk time, inversely associated with grip strength, and not associated with 20-m walking speed.

CONCLUSIONS

At least two inflammatory components can be identified in an older population, and these components have inconsistent associations with different aspects of physical performance.

Candidate gene polymorphisms and the 9p21 locus in acute coronary syndromes

It is now widely accepted that the classic environmental risk factors for atherosclerosis only partly explain the incidence of coronary artery disease and the development of acute coronary syndromes. Therefore, genetic factors that vary among human populations seem to be involved in the clinical manifestations of such patients. Substantial data suggest that a significant proportion of genetic polymorphisms involved in endothelial function, inflammation, lipid metabolism, thrombosis and fibrinolysis are often present in patients with acute coronary syndromes. In particular, a common variant on chromosome 9p21 was recently identified to affect the risk of myocardial infarction. Here, we review the progress of candidate gene studies and genome-wide association studies in identifying the genetic bases of complex cardiovascular diseases such as acute coronary syndromes.

Genetic polymorphisms for the study of multifactorial stroke

Single-gene disorders explain only a minority of stroke cases. Stroke represents a complex trait, which is usually assumed to be polygenic. On this topic, the role of a wide number of candidate genes has been investigated in stroke through association studies, with controversial results. Therefore, it is difficult for the clinician to establish the validity and the level of clinical applicability of the previously reported associations between genetic factors and stroke. This review is an update and an extensive analysis of the more recent association studies conducted in stroke. We evaluated a number of studies on several candidate genes (including F5, F2, FGA/FGB/FGG, F7, F13A1, vWF, F12, SERPINE1, ITGB3/PLA1/PLA2/ITGA2B, ITGA2, GP1BA, ACE, AGT, NOS3, APOE, LPL, PON1, PDE4D, ALOX5AP, MTHFR, MTR, and CBS), providing a final panel of genes and molecular variants. We categorized this panel in relation to the degree of association with stroke, supported by the results of meta-analyses and case-control studies. Our findings could represent a useful tool to address further molecular investigations and to realize more detailed meta-analyses.

Noninvasive Detection and Localization of Vulnerable Plaque and Arterial Thrombosis With Computed Tomography Angiography/Positron Emission Tomography

Background— It has been shown that plaque uptake of fluorodeoxyglucose is proportional to macrophage density. We tested the hypothesis that arterial thrombosis occurs in areas with high fluorodeoxyglucose uptake and that computed tomography angiography (CTA) can detect thrombi in vessels.

Methods and Results— Twenty New Zealand White rabbits were studied before and after atherosclerosis induction through de-endothelialization and a high-cholesterol diet; 14 were then thrombus triggered. CTA/positron emission tomography scans were performed before cholesterol diet, at the middle diet feeding, at the end of diet feeding, and after triggering. Serum inflammatory markers were measured. Maximal standardized uptake value was measured over the thoracic and upper and lower abdominal aortas and correlated with thrombosis and macrophage density on sections from the same sites. Aortic diameters averaged 2.84±1.16 mm. The sensitivity, specificity, and accuracy of CTA for detecting thrombi were 92%, 89%, and 90%, respectively. Plasminogen activator inhibitor-1 and C-reactive protein levels increased with atherosclerosis and thrombosis triggering. Maximal standardized uptake value at baseline was 0.62±0.13, 0.96±0.33 at the middle of feeding, and 1.06±0.38 at the end of feeding. Segments that developed thrombosis had the highest maximal standardized uptake value of 1.32±0.69 (113% increase; P =0.002) and had a 129% increase in macrophage density compared with segments without thrombi ( P =0.01).

Conclusions— Fluorodeoxyglucose uptake was proportional to the duration of cholesterol feeding and peaked with plaque disruption and thrombosis. CTA was highly accurate in detecting thrombi. Our findings in this animal model of atherosclerotic plaques with high macrophage density showed that CTA/positron emission tomography can be used to identify and localize inflamed plaques and thrombosis. With the currently available technology and nuclear tracers, however, many challenges remain before clinical applications are possible.

Synergistic effects of the polymorphisms in the PAI-1 and IL-6 genes with smoking in determining their associated risk with coronary artery disease

OBJECTIVES

To assess the relationship between IL-6 and PAI-1 polymorphisms and coronary artery disease (CAD) and to observe the interactions between these polymorphic variants and smoking in the CAD risk.

DESIGN AND METHOD

The study population consisted of 178 patients with angiographically documented CAD and 202 blood donors. The analyses of genetic polymorphisms were performed using the PCR-RFLP method.

RESULTS

The frequency of PAI-1 5G allele was higher in the entire CAD group than in control group (p=0.04, OR=1.35). Also the 5G allele carriers (4G5G+5G5G) were more frequent in patients than in controls (p=0.03, OR=1.93). The number of women carrying 5G allele was again significantly higher among patients (OR=10.95 p=0.0075). The IL-6 C allele frequency was higher only in the CAD male subgroup (p=0.035, OR=1.44). We found synergistic and cumulative effects between specific genotype patterns and smoking in determining the risk of CAD, especially between PAI-1(4G5G+5G5G)+IL-6(CC) and smoking (SIM=4.18 and p=0.0005, OR=9.20, respectively).

CONCLUSIONS

There are synergistic and cumulative effects of 5G allele of PAI-1 polymorphism and C allele of IL-6 polymorphism with smoking in determining their associated risk with CAD.

Binding of upstream stimulatory factor 1 to the E-box regulates the 4G/5G polymorphism-dependent plasminogen activator inhibitor 1 expression in mast cells

BACKGROUND

Plasminogen activator inhibitor (PAI)-1 is a key regulator of the fibrinolytic system. PAI-1 levels are markedly elevated in the asthmatic airways. The 4G/5G polymorphism of the PAI-1 gene is associated with allergic asthma.

OBJECTIVE

To characterize the mechanisms of the 4G/5G-dependent PAI-1 expression in mast cells (MCs), a major source of PAI-1 and key effector cells in asthma.

METHODS

Transcription of PAI-1 was assessed by transiently transfecting human MC line (HMC-1) cells with the luciferase-tagged PAI-1 promoters containing the 4G or 5G allele (4G-PAI-1 or 5G-PAI-1 promoter). Upstream stimulatory factor (USF)-1 and the E-box interactions were studied by electrophoretic mobility shift assays and supershift assays. Expression of USF-1 was determined by Western blot analysis.

RESULTS

The 4G-PAI-1 promoter has higher promoter activity than the 5G-PAI-1 promoter in stimulated HMC-1 cells, and the E-box adjacent to the 4G/5G site (E-4G/5G) regulates the genotype-specific PAI-1 transcription. USF-1 binds to the E-4G with greater affinity than to the E-5G. USF-1 level is increased in HMC-1 cells after stimulation, and elevated USF-1 enhances PAI-1 transcription. Overexpression of wild-type USF-1 or dominant-negative USF remedies the 4G/5G-dependent PAI-1 transcription.

CONCLUSION

Binding of USF-1 to the E-4G/5G regulates the 4G/5G polymorphism-dependent PAI-1 expression in MCs.

Plasminogen activator inhibitor-1 polymorphism (4G/5G) predicts recurrence in nonhyperlipidemic postinfarction patients

OBJECTIVE

Nonhyperlipidemic postinfarction patients are at high risk for recurrent coronary events by virtue of incident myocardial infarction (MI); however, few studies assess risk beyond incident MI. The aim of this study was to assess such risk as a function of 37 atherosclerosis-associated genetic polymorphisms and 17 blood marker variables.

METHODS AND RESULTS

Screening of polymorphisms in nonhyperlipidemic postinfarction patients revealed significant risk only for the 4G/5G insertion/deletion polymorphism in the promoter of the plasminogen-activator inhibitor-1 (PAI-1) gene. Outcome event mapping, an exploratory data analysis tool, was then applied to define a subgroup (182 patients from total study population of 846 nondiabetic patients) exhibiting maximal functional dependence of risk on the PAI-1 polymorphism. Cox multivariable regression analyses within the subgroup adjusted for significant clinical covariates and medication use as a function of the PAI-1 polymorphism and 17 atherosclerosis-associated blood markers revealed significant risk for patients homozygous for the 4G allele (hazard ratio 4.30, 95% CI 1.98 to 9.33, P=0.00023), and lack of significant risk-association with any blood marker.

CONCLUSIONS

In a subgroup of normolipidemic postinfarction patients, only the PAI-1 4G/5G polymorphism was associated with recurrent risk from a set of atherosclerosis-associated genetic polymorphisms and blood markers.

4G/5G polymorphism of PAI-1 gene and Alu-repeat I/D polymorphism of TPA gene in Turkish patients with polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is one of the most encountered endocrine malfunctions. PCOS patients have enhanced activation of the blood coagulation system.

METHODS

Eighty-six young women with PCOS and 70 healthy control women were included in our study. PCOS patients and controls were matched for age, body mass index, and allele frequency. Genetic analysis of TPAI and PAI-1 were performed in all subjects.

RESULTS AND CONCLUSIONS

No statistically significant differences have been detected about the ratios of genotypes resulting from PAI-1 promotor 4G/5G gene polymorphism. PAI-1 765 4G/5G gene polymorphism and TPA gene's Alu-repeat insertion/deletion (I/D) polymorphism ratios were not different from the controls. In this study it is shown by the analysis of TPA gene's Alu-repeat insertion/deletion (I/D) polymorphism the PCOS patients with genotype II had lowers total cholesterol and LDL-cholesterol levels.

Association of plasminogen activator inhibitor (PAI)-1 (SERPINE1) SNPs with myocardial infarction, plasma PAI-1, and metabolic parameters: the HIFMECH study

OBJECTIVE

The purpose of this study was to investigate the effects of plasminogen activator inhibitor-1 (PAI-1) gene (SERPINE1) single nucleotide polymorphisms (SNPs) on the risk of myocardial infarction (MI), on PAI-1 levels, and factors related to the metabolic syndrome.

METHODS AND RESULTS

Eleven SNPs capturing the common genetic variation of the SERPINE1 gene were genotyped in the HIFMECH study. In the 510 male cases and their 543 age-matched controls, a significant gene-smoking interaction was observed. In nonsmokers, the rs7242-G allele was more frequent in cases than in controls (0.486 versus 0.382, P=0.013) whereas the haplotype derived from the rs2227631 (-844A>G)-G and rs2227683-A alleles was approximately 3-fold lower in cases than in controls (0.042 versus 0.115, P=0.006). SERPINE1 haplotypes explained 3.5% (P=0.007) of the variability of PAI-1 levels, which was attributable to the combined effects of 3 SNPs, -844A>G, rs2227666, and rs2227694. The rs6092 (Ala15Thr) and rs7242 SNPs acted additively to explain 4.4% of the variability of plasma insulin levels and 1.6% of the variability of BMI (P<10(-3) and P=0.023, respectively).

CONCLUSIONS

SERPINE1 haplotypes are mildly associated with plasma levels of PAI-1 and with the risk of MI in nonsmokers. They are also associated with insulin levels and BMI.

Increased mortality in septic shock with the 4G/4G genotype of plasminogen activator inhibitor 1 in patients of white descent

OBJECTIVE

To evaluate the effect of the 4G/5G PAI-1 gene polymorphism on the development of organ failure and outcome in critically ill patients with septic syndromes.

DESIGN AND SETTING

Prospective, observational study in a medical intensive care unit of a university hospital.

PATIENTS

224 consecutively admitted patients.

INTERVENTIONS

Epidemiological data, severity scores, and the primary site of infection were recorded. DNA genotyping of the PAI-1, TNF-beta, and IL1-ra genes, and measurement of plasma PAI-1 antigen and D-dimer were carried out.

MEASUREMENTS

The primary outcome variables were organ dysfunction and mortality.

RESULTS

Eighty-eight subjects had septic shock at ICU entry or within 48 h from admission. Homozygotes for the 4G allele exhibited higher plasma concentrations of PAI-1 antigen and D-dimer than 4G/5G and 5G/5G subjects). ICU mortality was 44.0% in patients with 4G/4G, 23.4% in 4G/5G and 12.5% in 5G/5G, mainly due to multiorgan failure. After adjusting for SAPS II at admission the genotypes independently associated with ICU mortality in septic shock were TNF-B2/B2 (OR 2.83, 1.04-7.67) and 4G/4G of PAI-1 (OR 2.23, 1.02-4.85). The PAI-1 genotype did not determine susceptibility to infection or the outcome in nonseptic systemic inflammatory response syndrome, sepsis, severe sepsis, and nosocomial septic shock.

CONCLUSIONS

Homozygosity for 4G of the PAI-1 gene confers an increase in the risk of mortality in adult patients with septic shock due to a greater organ failure.