Effect of LSR polymorphism on blood lipid levels and age-specific epistatic interaction with the APOE common polymorphism.

The lipolysis stimulated lipoprotein receptor (LSR) is an apolipoprotein (Apo) B and ApoE receptor that participates in the removal of triglyceride-rich lipoproteins during the postprandial phase. LSR gene is located upstream of APOE, an important risk factor for cardiovascular disease (CVD). Since the APOE common polymorphism significantly affects the variability of lipid metabolism, this study aimed to determine the potential impact of a functional SNP rs916147 in LSR gene on lipid traits in healthy subjects and to investigate potential epistatic interaction between LSR and APOE. Unrelated healthy adults (N = 432) and children (N = 328, <18 years old) from the STANISLAS Family Study were used. Age-specific epistasis was observed between APOE and LSR, reversing the protective effect of APOE ε2 allele on cholesterol, ApoE and low-density lipoprotein levels (ß: .114, P: .777 × 10-8 , ß: .125, P: .639 × 10-3 , ß: .059, P: .531 × 10-3 , respectively). This interaction was verified in an independent adult population (n = 1744). These results highlight the importance of the LSR polymorphism and reveal the existence of complex molecular links between LSR and ApoE for the regulation of lipid levels, revealing potential new pathways of interest in type III hyperlipidemia and its involvement in CVD pathology.

IL6R haplotype rs4845625*T/rs4537545*C is a risk factor for simultaneously high CRP, LDL and ApoB levels.

Interleukin 6 receptor (IL-6R), mediating IL-6's biological functions, plays an important role in different diseases such as diabetes, obesity and cardio-vascular diseases. In this study, we investigated the effects of two single nucleotide polymorphisms (SNPs), within the IL-6R loci, previously associated with C-reactive protein (CRP) and coronary heart diseases risk, and with controversial effects on lipids traits: SNP rs4845625 and SNP rs4537545. The results showed that both investigated SNPs were antagonistically related with CRP levels; the minor rs4845625*T allele was associated with increased CRP levels (P-value=0.011), while the minor rs4537545*T allele was associated with decreased CRP levels (P-value=0.009). Interestingly, the minor rs4845625*T allele was significantly associated with higher low-density lipoprotein cholesterol (LDL-C) and ApoB levels (P=0.007 and P=0.009 respectively). Haplotype analysis showed that the TC haplotype, having the minor rs4845625*T allele, was related simultaneously with increased levels of CRP, LDL-C and ApoB levels, thus could be considered as a risk factor. Our investigation detects for the first time an independent effect of rs4845625 on LDL-C and ApoB traits, explaining an important range of those traits variability (3.49 and 5.57% respectively). Our findings might be of high clinical significance in pharmacogenomics studies of tocilizumab for which IL-6R is target.

VEGF-related polymorphisms identified by GWAS and risk for major depression.

Depression is a common, severe, disabling mental disease that affects millions of people of all ages worldwide. Various studies have shown that neurotrophic/growth factors have a key role in depression and, more specifically, vascular endothelial growth factor (VEGF) is implicated in the pathogenesis of depression. The purpose of this study was to investigate the potential links between four VEGF-related single-nucleotide polymorphisms (SNPs), previously identified through a genome-wide association study (GWAS) and depression. The direct effects and epistatic interactions of the four VEGF-related SNPs (rs10738760, rs6921438, rs6993770 and rs4416670) on depression were investigated through a case-control study including 437 individuals diagnosed with depression and 477 healthy volunteers as controls. Gender, age and body mass index influence was additionally analyzed. The SNP rs4416670 was associated with increased risk for depression (OR: 1.60, P: 0.010). This result demonstrates the existence of relationships between VEGF genetic determinants and depression. This novel association reveals new molecular mechanisms suggesting the potential role of VEGF in depression development that could help to promote a personalized prediction for this severe common disease.

A multi-stage multi-design strategy provides strong evidence that the BAI3 locus is associated with early-onset venous thromboembolism.

BACKGROUND: Factor VIII (FVIII) and von Willebrand factor (VWF) are two known quantitative risk factors for venous thromboembolism (VTE). OBJECTIVES: To identify new loci that could contribute to VTE susceptibility and to modulating FVIII and/or VWF levels. PATIENTS/METHODS: A pedigree linkage analysis was first performed in five extended French-Canadian families, including 253 individuals, to identify genomic regions linked to FVIII or VWF levels. Identified regions were further explored using 'in silico' genome-wide association studies (GWAS) data on VTE (419 patients and 1228 controls), and two independent case-control studies (MARTHA and FARIVE) for VTE, gathering 1166 early-onset patients and 1408 healthy individuals. Single nucleotide polymorphisms (SNPs) associated with VTE risk were further investigated in relation to plasma levels of FVIII and VWF in a cohort of 108 healthy nuclear families. RESULTS: Four main linkage regions were identified, among which the well-characterized ABO locus, the recently identified STAB 2 gene, and a third one, on chromosome 6q13-14, harbouring four non-redundant SNPs, associated with VTE at P < 10(-4) in the GWAS dataset. The association of one of these SNPs, rs9363864, with VTE was further replicated in the MARTHA and FARIVE studies. The rs9363864-AA genotype was associated with a lower risk for VTE (OR = 0.58 [0.42-0.80], P = 0.0005) but mainly in non-carriers of the FV Leiden mutation. This genotype was further found to be associated with the lowest levels of FVIII (P = 0.006) and VWF (P = 0.001). CONCLUSIONS: The BAI3 locus where the rs9363864 maps is a new candidate for VTE risk.

Genomics and the prospects of existing and emerging therapeutics for cardiovascular diseases.

The growing knowledge about genetic influence on cardiovascular diseases (CVD) combined with the recently generated amounts of genomic data hold promise to the identification of new markers for atherosclerotic CVD. Cardiovascular pharmacogenomics and pharmacogenetics have now the potential for leading to identification of genetic contributors and therefore to the development of predictive genetic tests that could optimize drugs efficacy and minimize toxicity. Clinical studies have shown that genetic variations within cytochromes P450 (CYPs), 3-Hydroxyl-3-Methylglutaryl Coenzyme A Reductase (HMGCR) and apolipoprotein E (APOE) genes influence individual's response to lipid lowering statins. Furthermore, development of antagonists or inhibitors of molecules such as peroxisome proliferator-activated receptors (PPARs), lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), angiotensin-converting enzyme (ACE), angiotensin receptors and tumor necrosis factor (TNF)-alpha could be another alternative to prevent atherosclerosis. In addition, novel molecules under the name of biologics including family of peptides such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), urocortin, apelin and antimicrobial peptides (AMPs) could be considered as new targets for the prevention and treatment of CVD. In this article, we will focus mainly on recent genomic advances in the development of new markers and therapeutic agents for CVD. We present an array of molecules that could have pharmacological benefit for the treatment of heart disease. We also discuss in details new strategies including biologics, which are actually the focus of companies for clinical development of therapeutic drugs. All these efforts provide optimism and attractive promise to cure CVD.

Association of human cathelicidin (hCAP-18/LL-37) gene expression with cardiovascular disease risk factors.

BACKGROUND AND AIMS: Antimicrobial peptides (AMPs) are components of the innate immune system. In addition, evidence suggests that these peptides are associated with various inflammatory diseases. We examined whether expression of the cathelicidin LL-37 in peripheral blood mononuclear cells (PBMCs) is associated with cardiovascular risk factors. METHODS AND RESULTS: A total of 90 men and 87 women selected from STANISLAS cohort were studied. Expression of LL-37 mRNA isolated from PBMCs of these subjects was quantified by quantitative RT-PCR. Anthropometric measurements and biochemical profiles were assessed for each individual. In women, LL-37 mRNA expression was significantly and positively correlated with body mass index (BMI) (p

Five-year alterations in BMI are associated with clustering of changes in cardiovascular risk factors in a gender-dependant way: the Stanislas study.

OBJECTIVE: The purpose of the present longitudinal study was to describe the associations between the 5-year changes in body mass index (BMI) and alterations in the clusters of metabolic syndrome (MS)-related factors. METHODS: The study population comprised 1099 middle-aged adults drawn from the Stanislas study. Individuals were stratified into four groups according to the 5-year changes in BMI (weight loss (<0 kg/m(2)), and weight gain (0-1, 1-2 and >2 kg/m(2))). Changes in various MS-related variables and clusters were compared between groups: anthropometric indices, blood pressure, lipid and inflammatory markers, liver enzymes, uric acid and the five summary factors extracted by using factor analysis ('risk lipids', 'liver enzymes', 'inflammation', 'protective lipids' and 'blood pressure'). RESULTS: There was a strong linear trend between increasing BMI and worsening of risk lipids and blood pressure factors for both men and women (P

P-selectin polymorphisms' influences on P-selectin serum concentrations and on their familial correlation: the STANISLAS family study.

BACKGROUND: P-selectin is an adhesion molecule known to be involved in the pathogenesis of several diseases through its major role in the initial phase of leukocytes recruitment during inflammation. However, genetic characterization of soluble P-selectin remains unclear. OBJECTIVES: In the STANISLAS cohort, we study the familial correlations of P-selectin levels and investigate the association of six P-selectin polymorphisms (C-2123G, A-1969G, S290N, N562D, V599L and T715P) and cardiovascular risk factors with P-selectin concentrations. PATIENTS/METHODS: Full phenotypic and genotypic information was available for 136 healthy families composed of both natural parents and at least one child (boys, n = 125; and girls, n = 139) aged more than 4 years. RESULTS: While no correlation was observed between spouses, family correlations of P-selectin concentrations were highly significant for sibling (0.50 +/- 0.12, P < 10(-3)) and child-parent pairs (0.42 +/- 0.04, P < 10(-3)). P-selectin haplotypes explained about 25% of the variability of P-selectin concentrations, this effect being mainly due to the additive effects of two polymorphisms, V599L and T715P. After adjusting for the effect of the P-selectin polymorphisms, the sibling and child-parent correlations decreased to (0.39 +/- 0.08, P < 10(-4)) and (0.32 +/- 0.06, P < 10(-4)), respectively. CONCLUSIONS: In the present study, we showed that two P-selectin polymorphisms, V599L and T715P, explained about 25% of the variability of P-selectin concentrations and accounted for about 40% of their family resemblance. These results would suggest a genetic influence on P-selectin concentrations beyond the contribution of the P-selectin gene.

Genetic Polymorphism of CYP2C19 gene in the Stanislas cohort. A link with inflammation.

CYP2C19, a member of the cytochrome P450 family, metabolises arachidonic acid to produce epoxyeicosanoid acids, which are involved in vascular tone and inflammation. Thus, this study describes the possible relationship between a CYP2C19 polymorphism (681G>A) and three inflammatory markers: interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and high sensitivity C-reactive protein (hs-CRP) in healthy individuals. In a sub-sample of 178 men and 181 women from the Stanislas study, we quantified plasma IL-6 and TNF-alpha concentrations by using an enzyme-linked immunosorbent assay, and serum hs-CRP concentration by immunonephelometry. The CYP2C19 681G>A polymorphism was genotyped using the kinetic thermocycling allele specific PCR method. In the Stanislas cohort, the frequency of the allele CYP2C19*2 (681A) was 17.8%. Circulating levels of inflammatory factors were increased in individuals homozygous for the defective allele CYP2C19*2 (A) notably IL-6 in the whole sample (P= 0.0008) and hs-CRP only in women (P= 0.008), with a significant interaction with sex (P= 0.005), in comparison to carriers of one copy or more of the wild type allele CYP2C19*1 (G). Only a trend of association (P= 0.089) was found between this polymorphism and TNF-alpha concentration in the whole sample. The association between CYP2C19*2 polymorphism and inflammatory markers' concentrations could suggest that CYP2C19 may be considered as a new candidate gene for cardiovascular risks via inflammation.

[A prospective study on the prevalence of metabolic syndrome among healthy French families: the importance of plasma concentration of TNF-alpha in addition to its genetic polymorphism]. / Une étude prospective de la prévalence du syndrome métabolique dans des familles Françaises supposées saines.

Metabolic syndrome (MS) is a cluster of synergistically interacting cardiovascular risk factors which may have serious consequences for the development of cardiovascular disease and diabetes. In this study, we aimed to estimate the prevalence of MS within presumably healthy French families of the STANISLAS cohort, and to observe biological parameters involved in cardiovascular diseases among the offspring of MS subjects. 371 apparently healthy families (1366 individuals) were examined at two visits with a five-year interval (t0 and t+5). MS prevalence was assessed among parents following the ATP-III definition. Our results show that MS is present in presumably healthy adults of the STANISLAS cohort and increases with age. Moreover, low HDL-C and TNF-alpha may play an important role in the development of MS in childhood, at least in our population. Therefore, a systematic tracking of MS appears to be all the more important as it will permit early management of MS in parents and the installation of efficient preventive measures in children including specific advice for diet and physical activity.

[Pharmacogenomics and pharmacoproteomics: a strategy for cardio-vascular drugs]. / Pharmacogénomique et pharmacoprotéomique.

The development of personalized medicine will require improved knowledge of biological variability, particularly concerning the important impact of each individual's genetic makeup. A five-step strategy can be followed when trying to identify genes and gene products involved in differential responses to cardiovascular drugs: 1) Pharmacokinetic-related genes and phenotypes; (2) Pharmacodynamic targets, genes and products; (3) Cardiovascular diseases and risks depending on specific or large metabolic cycles; (4) Physiological variations of previously identified genes and proteins; (5) Environmental influences on them. After summarizing the most well known genes involved in drug metabolism, we used statins as an example. In addition to their economic impact, statins are generally considered to be of significant importance in terms of public health. Individuals respond differently to these drugs depending on multiple polymorphisms. Applying a pharmacoproteomic strategy, it is important to use available information on peptides, proteins and metabolites, generally gene products, in each of the five steps. A profiling approach dealing with genomics as well as proteomics is useful. In conclusion, the ever growing volume of available data will require an organized interpretation of variations in DNA and mRNA as well as proteins, both on the individual and population level.

Heritability of serum hs-CRP concentration and 5-year changes in the Stanislas family study: association with apolipoprotein E alleles.

We aimed at estimating additive genetic heritability, household component effect and the influence of common alleles of the apolipoprotein E gene (APOE) on serum high-sensitivity C-reactive protein (hs-CRP) concentrations and the subsequent changes over 5 years. A sub-sample of 320 nuclear families was randomly selected from the Stanislas Family Study. Serum hs-CRP concentration was measured by immunonephelometry at entrance and after 5 years. APOE alleles were determined by restriction fragment length polymorphism. After adjustment for covariates, the number of the epsilon4 allele was negatively associated with serum concentration of hs-CRP in the whole sample, at entrance and 5 years later, without significant interaction with sex by generation groups (P=0.003 and P=0.0003, respectively). However, no significant association was found between epsilon4 allele and 5-year changes in hs-CRP concentration. Using a variance component analysis, no significant genetic influence was shown in family aggregation of both hs-CRP measurements and 5-year changes; the household common component was between 6.5 and 12.8%. In addition, after adjustment for APOE gene polymorphisms, degrees of resemblance were almost unchanged. In the Stanislas Family Study, epsilon4 allele of the APOE gene was associated with lower hs-CRP concentration, but not with 5-year changes. However, variance component analysis did not evidence a significant polygenic effect.

Apolipoprotein E polymorphism is not associated with lipid levels and coronary artery disease in Greek patients with familial hypercholesterolaemia.

Familial hypercholesterolaemia is a genetic disorder characterised by high low-density lipoprotein (LDL) cholesterol concentrations, which frequently gives rise to premature coronary artery disease (CAD). The clinical expression of familial hypercholesterolaemia is highly variable even in patients carrying the same LDL receptor gene mutation. This variability may be due to environmental and other genetic factors. Apolipoprotein E (Apo-E) has been extensively studied for its effects on the phenotype of familial hypercholesterolaemia. In this study we examined the influence of Apo-E genotype on lipid parameters and the incidence of CAD in 93 Greek patients with familial hypercholesterolaemia. Apo-E E2, E3 and E4 allele frequencies were 0.06, 0.86 and 0.09 respectively. The levels of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, apolipoproteins A and B and lipoprotein alpha did not differ significantly among carriers and non-carriers of the E4 allele. The prevalence of CAD and hypertension did not differ either. Our results suggest that the E4 allele is not associated with lipid levels or with the prevalence of CAD among familial hypercholesterolaemia patients of the Greek population.

Down-regulation of astroglial CYP2C, glucocorticoid receptor and constitutive androstane receptor genes in response to cocaine in human U373 MG astrocytoma cells.

Psychostimulant drugs abuse is associated with an increased risk of stroke. Cytochromes P450 (CYP), especially the astrocytic members of the CYP2C subfamily may play an important role in the modulation of cerebrovascular functions, by generating vasodilatator metabolites from arachidonic acid (AA). Our study examined the regulation of CYP2C genes in response to cocaine or amphetamine in the human astrocyte-like U373 MG cells, using reverse transcription-polymerase chain reaction (RT-PCR) and western-blot analysis. A treatment for 48h with increasing concentrations of cocaine caused a significant down-regulation of CYP2C8 and CYP2C9 genes and decreased the protein level. These effects were not observed with amphetamine. One mechanism of the CYP2C mRNA regulation implicates various specific receptors including glucocorticoid receptor (GR) and constitutive androstane receptor (CAR). Effects of cocaine on CYP2C were accompanied by a decrease in the GR and CAR gene expression suggesting that these nuclear receptors could be involved in the CYP2C repression by cocaine in the U373 MG cell line. These findings represent a possible molecular mechanism involved in the cerebrovascular risk associated with cocaine abuse.

Association of CYP2A6*1B genetic variant with the amount of smoking in French adults from the Stanislas cohort.

This study was designed in order to investigate the influence of the genetic polymorphism of CYP2A6 on the amount of smoking. In all, 463 French adults included in the Stanislas cohort were studied and underwent two examinations at 5 years distance (t0 and t(+5) years). Information on their smoking habits was collected. They were genotyped by RFLP for the CYP2A6*1A, CYP2A6*1B and CYP2A6*4 alleles. CYP2A6*1B and CYP2A6*4 allele frequencies were 32 and 4%, respectively. The subjects carrying the CYP2A6*1B allele oxidize nicotine to cotinine faster than subjects with the CYP2A6*1A allele. The number of cigarettes smoked per day was significantly higher in the CYP2A6*1B/*1B group as compared to the CYP2A6*1A/*1A group (P = 0.01 at t0; P = 0.001 t(+5) years), with a larger increase in their daily cigarettes consumption over the 5-year period (P = 0.006). No significant difference in the smoking status was observed according to the CYP2A6 genotype. These data suggest that the CYP2A6*1B is associated with the number of cigarettes smoked per day.