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BACKGROUND: Saturated fatty acids (SFAs) of different chain lengths have unique metabolic and biological effects, and a small number of recent studies suggest that higher circulating concentrations of the very-long-chain SFAs (VLSFAs) arachidic acid (20:0), behenic acid (22:0), and lignoceric acid (24:0) are associated with a lower risk of diabetes. Confirmation of these findings in a large and diverse population is needed. OBJECTIVE: We investigated the associations of circulating VLSFAs 20:0, 22:0, and 24:0 with incident type 2 diabetes in prospective studies. METHODS: Twelve studies that are part of the Fatty Acids and Outcomes Research Consortium participated in the analysis. Using Cox or logistic regression within studies and an inverse-variance-weighted meta-analysis across studies, we examined the associations of VLSFAs 20:0, 22:0, and 24:0 with incident diabetes among 51,431 participants. RESULTS: There were 14,276 cases of incident diabetes across participating studies. Higher circulating concentrations of 20:0, 22:0, and 24:0 were each associated with a lower risk of incident diabetes. Pooling across cohorts, the RR (95% CI) for incident diabetes comparing the 90th percentile to the 10th percentile was 0.78 (0.70, 0.87) for 20:0, 0.84 (0.77, 0.91) for 22:0, and 0.75 (0.69, 0.83) for 24:0 after adjustment for demographic, lifestyle, adiposity, and other health factors. Results were fully attenuated in exploratory models that adjusted for circulating 16:0 and triglycerides. CONCLUSIONS: Results from this pooled analysis indicate that higher concentrations of circulating VLSFAs 20:0, 22:0, and 24:0 are each associated with a lower risk of diabetes.

We sought to report the distribution of Lp(a) levels in the Mediators of Atherosclerosis among South Asians Living in America cohort of participants who were free from clinical atherosclerotic cardiovascular disease (ASCVD) at baseline and to evaluate the cross-sectional association with atherosclerosis measured by coronary artery calcification (CAC) and carotid intima media thickness. Among 886 participants (mean [SD] age: 55.4 [9.4] years, 54% male), median lipoprotein (a) level was 17 (9, 33) mg/dl. Compared with the lowest quartile (9 mg/dl), subjects in the highest Lp(a) quartile (33 to 178 mg/dl) were more likely to be women (51% vs 37%, p0.01) and had a higher mean (SD) total cholesterol (193 [37] mg/dl vs 181 [35] mg/dl, p0.01). CAC was present in 42% and both the presence and degree of CAC was similar across Lp(a) quartiles (p = 0.58). Median Interquartile range (IQR) common and internal carotid intima-media thickness (IMT) thicknesses were 0.84 (0.73, 0.98) mm and 1.12 (0.95, 1.34) mm, respectively, and were also similar across Lp(a) quartiles. After adjustment for cardiovascular risk factors, Lp(a) quartile had no association with prevalent CAC (p = 0.98), internal carotid IMT (p = 0.46), or common carotid IMT (p = 0.97). Among South Asian Americans, mean Lp(a) levels were higher than previous reports among Whites, Hispanic/Latino, and Chinese-Americans but lower than in Blacks. Unlike findings from other race/ethnic groups, Lp(a) levels were not associated with atherosclerosis among South Asian Americans.

Objective To conduct an epigenome-wide analysis of DNA methylation and obesity traits. Design and Methods We quantified DNA methylation in CD4+ T-cells using the Illumina Infinium Human Methylation450 array in 991 participants of the Genetics of Lipid Lowering Drugs and Diet Network. We modeled methylation at individual cytosine-phosphate-guanine (CpG) sites as a function of body mass index (BMI) and waist circumference (WC), adjusting for age, gender, study site, T-cell purity, smoking, and family structure. Results We found epigenome-wide significant associations between eight CpG sites and BMI and five CpG sites and WC, successfully replicating the top hits in whole blood samples from the Framingham Heart Study (n=2,377) and the Atherosclerosis Risk in Communities study (n=2,105). Top findings were in CPT1A (meta-analysis P= 3.5×10−37 for BMI and P=2.2×10−16 for WC), PHGDH (meta-analysis P= 4.7×10−15 for BMI and 2.2×10−8 for WC), CD38 (meta-analysis P= 3.7×10−11 for BMI and 6.1×10−13 for WC) and long intergenic non-coding RNA 00263 (meta-analysis P= 1.2×10−13 for BMI and 5.8×10−10 for WC), regions with biologically plausible relationships to adiposity. Conclusions This large-scale epigenome-wide study discovered and replicated robust associations between DNA methylation at CpG loci and obesity indices, laying the groundwork for future diagnostic and/or therapeutic applications.

Background: Statins increase the risk of new-onset type 2 diabetes mellitus. We aimed to assess whether this increase in risk is a consequence of inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the intended drug target.Methods: We used single nucleotide polymorphisms in the HMGCR gene, rs17238484 (for the main analysis) and rs12916 (for a subsidiary analysis) as proxies for HMGCR inhibition by statins. We examined associations of these variants with plasma lipid, glucose, and insulin concentrations; bodyweight; waist circumference; and prevalent and incident type 2 diabetes. Study-specific effect estimates per copy of each LDL-lowering allele were pooled by meta-analysis. These findings were compared with a meta-analysis of new-onset type 2 diabetes and bodyweight change data from randomised trials of statin drugs. The effects of statins in each randomised trial were assessed using meta-analysis.Findings: Data were available for up to 223 463 individuals from 43 genetic studies. Each additional rs17238484-G allele was associated with a mean 0·06 mmol/L (95% CI 0·05–0·07) lower LDL cholesterol and higher body weight (0·30 kg, 0·18–0·43), waist circumference (0·32 cm, 0·16–0·47), plasma insulin concentration (1·62%, 0·53–2·72), and plasma glucose concentration (0·23%, 0·02–0·44). The rs12916 SNP had similar effects on LDL cholesterol, bodyweight, and waist circumference. The rs17238484-G allele seemed to be associated with higher risk of type 2 diabetes (odds ratio [OR] per allele 1·02, 95% CI 1·00–1·05); the rs12916-T allele association was consistent (1·06, 1·03–1·09). In 129 170 individuals in randomised trials, statins lowered LDL cholesterol by 0·92 mmol/L (95% CI 0·18–1·67) at 1-year of follow-up, increased bodyweight by 0·24 kg (95% CI 0·10–0·38 in all trials; 0·33 kg, 95% CI 0·24–0·42 in placebo or standard care controlled trials and −0·15 kg, 95% CI −0·39 to 0·08 in intensive-dose vs moderate-dose trials) at a mean of 4·2 years (range 1·9–6·7) of follow-up, and increased the odds of new-onset type 2 diabetes (OR 1·12, 95% CI 1·06–1·18 in all trials; 1·11, 95% CI 1·03–1·20 in placebo or standard care controlled trials and 1·12, 95% CI 1·04–1·22 in intensive-dose vs moderate dose trials).Interpretation: The increased risk of type 2 diabetes noted with statins is at least partially explained by HMGCR inhibition.Funding: The funding sources are cited at the end of the paper.

BACKGROUND: The causal role of high density lipoprotein (HDL) cholesterol in cardioprotection has been questioned by genetic and randomized studies. Novel measures that relate to HDL function may contribute new information to prediction of cardiovascular risk. Apolipoprotein C-III (apoC-III) is a key regulator of lipoprotein metabolism. We investigated whether subspecies of HDL defined by apoC-III are associated with coronary heart disease (CHD). METHODS: We used immuno-affinity chromatography to measure the apoA-I concentrations of HDL that contains and lacks apoC-III in two prospective studies of adults free of CHD. In the Multi-Ethnic Study of Atherosclerosis (MESA), 5,657 participants (52% women; age 52–72 y) were followed for risk of CHD from 2000-2002 through 2013. In a case-cohort study nested within the Danish Diet, Cancer and Health (DCH) study, 3,642 participants (47% women; age 51-64 y) were followed from 1994-1997 through 2010. Subsequently, we conducted a meta-analysis that combined these results with the previously published findings from two cohort studies that used similar laboratory methodology to measure lipoproteins, totaling 2,997 incident cases. RESULTS: ApoC-III was found on 6-8% of apoA-I. The two HDL subspecies showed opposing associations with risk of CHD in each of the individual cohorts and in the meta-analysis (p-heterogeneity between the two subspecies

BACKGROUND: Abnormal lipid profiles have been associated with gestational diabetes mellitus (GDM), but studies with longitudinal measures of lipids throughout pregnancy are sparse. We aimed to characterize the longitudinal changes in lipid profiles throughout pregnancy and prospectively examine the associations of plasma lipid levels with risk of GDM. METHODS: This is a nested case-control study including 107 GDM cases and 214 matched non-GDM controls from participants in the NICHD Fetal Growth Studies-Singleton Cohort. Blood samples were longitudinally collected at gestational weeks 10–14, 15–26 (fasting sample), 23–31 and 33–39. Plasma concentrations of triglycerides, total cholesterol, and high-density lipoprotein cholesterol (HDL-C) were measured by enzymatic assays. Low-density lipoprotein cholesterol (LDL-C) was calculated by the Friedewald's formula. RESULTS: Plasma levels of triglycerides, total cholesterol, and LDL-C increased as pregnancy progressed. At gestational weeks 10–14, the adjusted odds ratios (ORs) of GDM comparing the highest versus lowest quartile were 3.15 (95% confidence interval [CI] 1.38–7.15; P for trend = 0.002) for triglycerides and 0.44 (95% CI 0.18–1.09; P for trend = 0.045) for HDL-C. At gestational weeks 15–26, the corresponding ORs were 6.57 (95% CI 2.25–19.17; P for trend = 0.001) for triglycerides and 0.23 (95% CI 0.08–0.63; P for trend = 0.005) for HDL-C. We observed no significant associations for total cholesterol and LDL-C levels with risk of GDM. CONCLUSIONS: Higher plasma triglyceride and lower HDL-C concentrations in early and mid-pregnancy were significantly associated with greater risk of GDM. Total cholesterol and LDL-C levels during pregnancy were not significantly associated with GDM risk. THE SIGNIFICANT FINDING (S) OF THE STUDY: Higher triglyceride and lower high-density lipoprotein cholesterol concentrations in early and mid-pregnancy are significantly related to greater risk of gestational diabetes mellitus. Total and low-density lipoprotein cholesterol levels during pregnancy were not associated with gestational diabetes risk. THIS STUDY ADDS: This study is based on longitudinal assessments of plasma lipid concentrations across pregnancy in a multiracial pregnancy cohort, which is uniquely suited to address temporal associations of plasma lipids in early and mid-pregnancy with the development of subsequent gestational diabetes.

IMPORTANCE: The role of ω-3 polyunsaturated fatty acids for primary prevention of coronary heart disease (CHD) remains controversial. Most prior longitudinal studies evaluated self-reported consumption rather than biomarkers. OBJECTIVE: To evaluate biomarkers of seafood-derived eicosapentaenoic acid (EPA; 20:5ω-3), docosapentaenoic acid (DPA; 22:5ω-3), and docosahexaenoic acid (DHA; 22:6ω-3) and plant-derived α-linolenic acid (ALA; 18:3ω-3) for incident CHD. DATA SOURCES: A global consortium of 19 studies identified by November 2014. STUDY SELECTION: Available prospective (cohort, nested case-control) or retrospective studies with circulating or tissue ω-3 biomarkers and ascertained CHD. DATA EXTRACTION AND SYNTHESIS: Each study conducted standardized, individual-level analysis using harmonized models, exposures, outcomes, and covariates. Findings were centrally pooled using random-effects meta-analysis. Heterogeneity was examined by age, sex, race, diabetes, statins, aspirin, ω-6 levels, and FADS desaturase genes. MAIN OUTCOMES AND MEASURES: Incident total CHD, fatal CHD, and nonfatal myocardial infarction (MI). RESULTS: The 19 studies comprised 16 countries, 45 637 unique individuals, and 7973 total CHD, 2781 fatal CHD, and 7157 nonfatal MI events, with ω-3 measures in total plasma, phospholipids, cholesterol esters, and adipose tissue. Median age at baseline was 59 years (range, 18-97 years), and 28 660 (62.8%) were male. In continuous (per 1-SD increase) multivariable-adjusted analyses, the ω-3 biomarkers ALA, DPA, and DHA were associated with a lower risk of fatal CHD, with relative risks (RRs) of 0.91 (95% CI, 0.84-0.98) for ALA, 0.90 (95% CI, 0.85-0.96) for DPA, and 0.90 (95% CI, 0.84-0.96) for DHA. Although DPA was associated with a lower risk of total CHD (RR, 0.94; 95% CI, 0.90-0.99), ALA (RR, 1.00; 95% CI, 0.95-1.05), EPA (RR, 0.94; 95% CI, 0.87-1.02), and DHA (RR, 0.95; 95% CI, 0.91-1.00) were not. Significant associations with nonfatal MI were not evident. Associations appeared generally stronger in phospholipids and total plasma. Restricted cubic splines did not identify evidence of nonlinearity in dose responses. CONCLUSIONS AND RELEVANCE: On the basis of available studies of free-living populations globally, biomarker concentrations of seafood and plant-derived ω-3 fatty acids are associated with a modestly lower incidence of fatal CHD.

At the cellular level, how excess adiposity promotes atherogenesis is not fully understood. One pathway involves secretion of adipokines that stimulate endothelial dysfunction through increased expression of adhesion molecules. However, the relationship of adiposity to adhesion molecules that promote atherosclerosis is largely unknown.Linear regression models were used to assess the sex-specific associations of soluble cellular adhesion molecules (sP- and sL-selectin, sICAM-1, sVCAM-1, and sHGF) and adiposity in 5,974 adults examined as part of the Multi-Ethnic Study of Atherosclerosis (MESA). Adiposity measures included body mass index (BMI), waist-to-hip-ratio (WHR), and computed tomography measures of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT).The mean age was 64 years and 52% were female. In multivariable models adjusting for traditional cardiovascular risk factors, sHGF was positively associated with BMI, WHR, and VAT in both males and females, and sP-selectin with WHR and VAT in males. sVCAM-1 was inversely associated with VAT in females only.Our results showed the relation of adiposity to soluble cellular adhesion proteins was similar across adiposity measures and for both sexes. However, the relationship between adiposity and sVCAM-1 and P-selectin may be modified by sex and the measure used to assess adiposity.

Tissue concentrations of omega-3 fatty acids may reduce cardiovascular disease risk, and genetic variants are associated with circulating fatty acids concentrations. Whether dietary fatty acids interact with genetic variants to modify circulating omega-3 fatty acids is unclear. We evaluated interactions between genetic variants and fatty acid intakes for circulating alpha-linoleic acid, eicosapentaenoic acid, docosahexaenoic acid, and docosapentaenoic acid.We conducted meta-analyses (N = 11 668) evaluating interactions between dietary fatty acids and genetic variants (rs174538 and rs174548 in FADS1 (fatty acid desaturase 1), rs7435 in AGPAT3 (1-acyl-sn-glycerol-3-phosphate), rs4985167 in PDXDC1 (pyridoxal-dependent decarboxylase domain-containing 1), rs780094 in GCKR (glucokinase regulatory protein), and rs3734398 in ELOVL2 (fatty acid elongase 2)). Stratification by measurement compartment (plasma versus erthyrocyte) revealed compartment-specific interactions between FADS1 rs174538 and rs174548 and dietary alpha-linolenic acid and linoleic acid for docosahexaenoic acid and docosapentaenoic acid.Our findings reinforce earlier reports that genetically based differences in circulating fatty acids may be partially due to differences in the conversion of fatty acid precursors. Further, fatty acids measurement compartment may modify gene-diet relationships, and considering compartment may improve the detection of gene-fatty acids interactions for circulating fatty acid outcomes.

The American College of Cardiology and American Heart Association have issued guidelines indicating that the contribution of apolipoprotein B-100 (ApoB) to cardiovascular risk assessment remains uncertain. The present analysis evaluates whether lipoprotein particle measures convey risk of coronary heart disease (CHD) in 4679 Multi-Ethnic Study of Atherosclerosis (MESA) participants.Cox regression analysis was performed to determine associations between lipids or lipoproteins and primary CHD events. After adjustment for nonlipid variables, lipoprotein particle levels in fourth quartiles were found to convey significantly greater risk of incident CHD when compared to first quartile levels (hazard ratio [HR]; 95% confidence interval [CI]): ApoB (HR, 1.84; 95% CI, 1.25-2.69), ApoB/ApoA-I (HR, 1.91; 95% CI, 1.32-2.76), total low-density lipoprotein-particles (LDL-P; HR, 1.77; 95% CI, 1.21-2.58), and the LDL-P/HDL-P (high-density lipoprotein-P) ratio (HR, 2.28; 95% CI, 1.54-3.37). Associations between lipoprotein particle measures and CHD were attenuated after adjustment for standard lipid panel variables. Using the American Heart Association/American College of Cardiology risk calculator as a baseline model for CHD risk assessment, significant net reclassification improvement scores were found for ApoB/ApoA-I (0.18; P=0.007) and LDL-P/high-density lipoprotein-P (0.15; P0.001). C-statistics revealed no significant increase in CHD event discrimination for any lipoprotein measure.Lipoprotein particle measures ApoB/ApoA-I and LDL-P/high-density lipoprotein-P marginally improved net reclassification improvement scores, but null findings for corresponding c-statistic are not supportive of lipoprotein testing. The attenuated associations of lipoprotein particle measures with CHD after the adjustment for lipids indicate that their measurement does not detect risk that is unaccounted for by the standard lipid panel. However, the possibility that lipoprotein measures may identify CHD risk in a subpopulation of individuals with normal cholesterol, but elevated lipoprotein particle numbers cannot be ruled out.

Gallbladder disease (GBD) has an overall prevalence of 10-40% depending on factors such as age, gender, population, obesity and diabetes, and represents a major economic burden. Although gallstones are composed of cholesterol by-products and are associated with obesity, presumed causal pathways remain unproven, although BMI reduction is typically recommended. We performed genetic studies to discover candidate genes and define pathways involved in GBD. We genotyped 15 241 women of European ancestry from three cohorts, including 3216 with GBD, using the Human cardiovascular disease (HumanCVD) BeadChip containing up to ~53 000 single-nucleotide polymorphisms (SNPs). Effect sizes with P-values for development of GBD were generated. We identify two new loci associated with GBD, GCKR rs1260326:T>C (P=5.88 × 10(-7), ß=-0.146) and TTC39B rs686030:C>A (P=6.95x10(-7), ß=0.271) and detect four independent SNP effects in ABCG8 rs4953023:G>A (P=7.41 × 10(-47), ß=0.734), ABCG8 rs4299376:G(>)T (P=2.40 × 10(-18), ß=0.278), ABCG5 rs6544718:T>C (P=2.08 × 10(-14), ß=0.044) and ABCG5 rs6720173:G>C (P=3.81 × 10(-12), ß(=)0.262) in conditional analyses taking genotypes of rs4953023:G>A as a covariate. We also delineate the risk effects among many genotypes known to influence lipids. These data, from the largest GBD genetic study to date, show that specific, mainly hepatocyte-centred, components of lipid metabolism are important to GBD risk in women. We discuss the potential pharmaceutical implications of our findings.European Journal of Human Genetics advance online publication, 29 April 2015; doi:10.1038/ejhg.2015.63.

L-selectin has been suggested to play a role in atherosclerosis. Previous studies on cardiovascular disease (CVD) and serum or plasma L-selectin are inconsistent. The association of serum L-selectin (sL-selectin) with carotid intima-media thickness, coronary artery calcium, ankle-brachial index (subclinical CVD), and incident CVD was assessed in 2403 participants in the Multiethnic Study of Atherosclerosis. Regression analysis and the Tobit model were used to study subclinical disease; Cox proportional hazards regression, for incident CVD. Mean age was 63 ± 10 years and 47% were male. Mean sL-selectin was significantly different across ethnicities. Within each race/ethnicity, sL-selectin was associated with age and sex; among non-Hispanic whites and African Americans, it was associated with smoking status and current alcohol use. sL-selectin levels did not predict subclinical or clinical CVD after correction for multiple comparisons. Conditional logistic regression models were used to study the association of plasma L-selectin and CVD in 154 incident CVD cases, and 306 age-, sex-, and ethnicity-matched control subjects. The median follow-up time was 8.5 years. L-selectin levels in plasma were significantly lower than in serum and the overall concordance was low. Plasma levels were not associated with CVD. In conclusion, in this large, multiethnic population, soluble L-selectin levels did not predict clinical or subclinical CVD.

Aims To investigate the causal role of high-density lipoprotein cholesterol (HDL-C) and triglycerides in coronary heart disease (CHD) using multiple instrumental variables for Mendelian randomization. Methods and results We developed weighted allele scores based on single nucleotide polymorphisms (SNPs) with established associations with HDL-C, triglycerides, and low-density lipoprotein cholesterol (LDL-C). For each trait, we constructed two scores. The first was unrestricted, including all independent SNPs associated with the lipid trait identified from a prior meta-analysis (threshold P < 2 × 10−6); and the second a restricted score, filtered to remove any SNPs also associated with either of the other two lipid traits at P ≤ 0.01. Mendelian randomization meta-analyses were conducted in 17 studies including 62,199 participants and 12,099 CHD events. Both the unrestricted and restricted allele scores for LDL-C (42 and 19 SNPs, respectively) associated with CHD. For HDL-C, the unrestricted allele score (48 SNPs) was associated with CHD (OR: 0.53; 95% CI: 0.40, 0.70), per 1 mmol/L higher HDL-C, but neither the restricted allele score (19 SNPs; OR: 0.91; 95% CI: 0.42, 1.98) nor the unrestricted HDL-C allele score adjusted for triglycerides, LDL-C, or statin use (OR: 0.81; 95% CI: 0.44, 1.46) showed a robust association. For triglycerides, the unrestricted allele score (67 SNPs) and the restricted allele score (27 SNPs) were both associated with CHD (OR: 1.62; 95% CI: 1.24, 2.11 and 1.61; 95% CI: 1.00, 2.59, respectively) per 1-log unit increment. However, the unrestricted triglyceride score adjusted for HDL-C, LDL-C, and statin use gave an OR for CHD of 1.01 (95% CI: 0.59, 1.75). Conclusion The genetic findings support a causal effect of triglycerides on CHD risk, but a causal role for HDL-C, though possible, remains less certain. M.V.H. was funded by a UK Medical Research Council Population Health Scientist Fellowship (G0802432). F.W.A. is supported by UCL Hospitals NIHR Biomedical Research Centre. D.I.S. is supported by a Medical Research Council Doctoral Training Award and a grant from the Rosetrees Foundation. ME.K. is supported by the National Institute of Aging and the National Heart, Lung and Blood Institute (HL36310). S.E.H. and P.J.T. are supported by the British Heart Foundation (BHF RG 08/008, PG/07/133/24260), UK Medical Research Council, the US National Institutes of Health (grant NHLBI 33014) and Du Pont Pharma, Wilmington, USA. N.J.S. holds a Chair funded by the British Heart Foundation and is an NIHR Senior Investigator. MI.K. is supported by the National Institute of Aging, the Medical Research Council, the British Heart Foundation, and the National Heart, Lung and Blood Institute and the Academy of Finland. A.D.H. and J.P.C. are supported by the National Institute of Health Research University College London Hospitals Biomedical Research Centre. Funding to pay the Open Access publication charges for this article was provided by RCUK.

International audience; BackgroundAlthough numerous candidate gene and genome-wide association studies have been performed on blood pressure, a small number of regulating genetic variants having a limited effect have been identified. This phenomenon can partially be explained by possible gene-gene/epistasis interactions that were little investigated so far.MethodsWe performed a pre-planned two-phase investigation: in phase 1, one hundred single nucleotide polymorphisms (SNPs) in 65 candidate genes were genotyped in 1,912 French unrelated adults in order to study their two-locus combined effects on blood pressure (BP) levels. In phase 2, the significant epistatic interactions observed in phase 1 were tested in an independent population gathering 1,755 unrelated European adults.ResultsAmong the 9 genetic variants significantly associated with systolic and diastolic BP in phase 1, some may act through altering the corresponding protein levels: SNPs rs5742910 (Padjusted≤0.03) and rs6046 (Padjusted =0.044) in F7 and rs1800469 (Padjusted ≤0.036) in TGFB1; whereas some may be functional through altering the corresponding protein structure: rs1800590 (Padjusted =0.028, SE=0.088) in LPL and rs2228570 (Padjusted ≤9.48×10-4) in VDR. The two epistatic interactions found for systolic and diastolic BP in the discovery phase: VCAM1 (rs1041163) * APOB (rs1367117), and SCGB1A1 (rs3741240) * LPL (rs1800590), were tested in the replication population and we observed significant interactions on DBP. In silico analyses yielded putative functional properties of the SNPs involved in these epistatic interactions trough the alteration of corresponding protein structures.ConclusionsThese findings support the hypothesis that different pathways and then different genes may act synergistically in order to modify BP. This could highlight novel pathophysiologic mechanisms underlying hypertension.

Chronic obstructive pulmonary disease (COPD) is linked to cardiovascular disease; however, there are few studies on the associations of cardiovascular genes with COPD. We assessed the association of lung function with 2100 genes selected for cardiovascular diseases among 20 077 European-Americans and 6900 African-Americans. We performed replication of significant loci in the other racial group and an independent consortium of Europeans, tested the associations of significant loci with per cent emphysema and examined gene expression in an independent sample. We then tested the association of a related lipid biomarker with forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio and per cent emphysema. We identified one new polymorphism for FEV1/FVC (rs805301) in European-Americans (p=1.3×10(-6)) and a second (rs707974) in the combined European-American and African-American analysis (p=1.38×10(-7)). Both single-nucleotide polymorphisms (SNPs) flank the gene for apolipoprotein M (APOM), a component of high-density lipoprotein (HDL) cholesterol. Both were replicated in an independent cohort. SNPs in a second gene related to apolipoprotein M and HDL, PCSK9, were associated with FEV1/FVC ratio among African-Americans. rs707974 was associated with per cent emphysema among European-Americans and African-Americans and APOM expression was related to FEV1/FVC ratio and per cent emphysema. Higher HDL levels were associated with lower FEV1/FVC ratio and greater per cent emphysema. These findings suggest a novel role for the apolipoprotein M/HDL pathway in the pathogenesis of COPD and emphysema.

The relation between dietary fish intake and brachial artery measures, including brachial artery flow-mediated dilation (FMD), has not been well established across sex and racial-ethnic groups.We hypothesized that consumption of nonfried fish and plasma phospholipid measures of long-chain omega-3 (n-3) fatty acids would be positively associated with larger FMD in men and women across racial-ethnic groups.We investigated cross-sectional associations of brachial artery measures with fish intake (ascertained with a food-frequency questionnaire) and plasma phospholipid omega-3 concentrations in 3045 adults, aged 45-84 y, who were free of clinical cardiovascular disease.In overall multivariate-adjusted analyses, there were no significant associations between fish intake or any brachial artery measures. However, when stratified by sex, there was an association between the highest quartile of nonfried fish consumption and a 0.10-mm lower (1 SD) brachial artery diameter in men (P = 0.01) and a 0.27% smaller FMD in women (P = 0.02) compared with the lowest quartile of nonfried fish intake in each respective sex strata. When stratified by race-ethnicity and race-ethnicity by sex, additional heterogeneity was noted, but results were difficult to interpret because of small sample sizes. Plasma phospholipid omega-3 concentrations showed a similar directionality of association with brachial artery measures observed for nonfried fish consumption, although statistical significance was not achieved in fully adjusted models.This study indicates that the association between nonfried fish intake and baseline brachial artery size varies by sex, with suggestive evidence of sex differences in the association between nonfried fish intake and FMD.

Disruption of the circadian system may be causal for manifestations of the metabolic syndrome (MetS).The objective was to study the associations of 5 CLOCK polymorphisms with MetS features by analyzing fatty acid (FA) composition from dietary and red blood cell (RBC) membrane sources.Participants (n = 1100) in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study were included. Dietary intake was estimated with a validated questionnaire. Anthropometric and biochemical measurements and genotypes were determined. Postprandial lipids and the FA composition of RBC membranes were analyzed.CLOCK single nucleotide polymorphisms were significantly associated with obesity and individual components of MetS. For single nucleotide polymorphism rs4580704, minor allele carriers had a 46% lower risk of hypertension than did noncarriers. The monounsaturated fatty acid (MUFA) content of RBC membranes, particularly oleic acid, changed according to CLOCK genetic variants (P0.05). We identified significant gene-diet interactions associated with MetS at the CLOCK locus. By dichotomizing MUFA intake, we found different effects across rs4580704 genotypes for glucose (P = 0.020) and insulin resistance (P = 0.026). The protective effect of the minor allele on insulin sensitivity was only present when MUFA intake was13.2% of energy. We also found different effects across CLOCK 3111T--C genotypes for saturated fatty acid intake (% of energy) (P = 0.017). The deleterious effect of gene variants on waist circumference was only found with high saturated fatty acid intakes (11.8%).CLOCK polymorphisms interact with FAs to modulate MetS traits. The dietary source and membrane content of MUFAs are implicated in the relations between alterations in the circadian system and MetS.

The scaffolding protein PDZ domain containing 1 (PDZK1) regulates the HDL receptor scavenger receptor class B type I. However, the effect of PDZK1 genetic variants on lipids and metabolic syndrome (MetS) traits remains unknown. This study evaluated the association of 3 PDZK1 single nucleotide polymorphisms (SNP) (i33968C > T, i15371G > A, and i19738C > T) with lipids and risk of MetS and their potential interactions with diet. PDZK1 SNP were genotyped in 1000 participants (481 men, 519 women) included in the Genetics of Lipid Lowering Drugs and Diet Network study. Lipoprotein subfractions were measured by proton NMR spectroscopy and dietary intake was estimated using a validated questionnaire. The PDZK1_i33968C > T polymorphism was associated with MetS (P = 0.034), mainly driven by the association of the minor T allele with higher plasma triglycerides (P = 0.004) and VLDL (P = 0.021), and lower adiponectin concentrations (P = 0.022) than in participants homozygous for the major allele (C). We found a significant gene × BMI × diet interaction, in which the deleterious association of the i33968T allele with MetS was observed in obese participants with high PUFA and carbohydrate (P-values ranging from 0.004 to 0.020) intakes. Conversely, a there was a protective effect in nonobese participants with high PUFA intake (P < 0.05). These findings suggest that PDZK1_i33968C > T genetic variants may be associated with a higher risk of exhibiting MetS. This gene × BMI × diet interaction offers the potential to identify dietary and other lifestyle changes that may obviate the onset of MetS in individuals with a specific genetic background.

The transcription factor 7-like 2 (TCF7L2) has been recently associated with diabetes risk, and it may exert its effect through metabolic syndrome (MetS)-related traits and be subjected to modification by environmental factors. We investigated the effect of single nucleotide polymorphisms (SNP), rs7903146 and rs12255372, within the TCF7L2 locus on postprandial lipemia and other MetS-related traits and their modulation by dietary fat. Data were collected from 1083 European Americans participating in the Genetics of Lipid Lowering Drugs and Diet Network Study. Carriers of the minor T allele at the C/T rs7903146 SNP had higher fasting plasma glucose (P = 0.012), lower homeostasis model assessment of beta cell function (P = 0.041), higher plasma VLDL (P = 0.035), and lower large LDL particle (P = 0.007) concentrations and higher risk of MetS (P = 0.011) than CC individuals. Moreover, we identified significant interactions between this SNP and PUFA intake modulating fasting VLDL particle concentrations (P = 0.016) and postprandial triglycerides (TG) (P = 0.028), chylomicrons (P = 0.025), total VLDL (P = 0.026), and large VLDL (P = 0.018) concentrations. Thus, only T allele carriers with a PUFA intakeor = 7.36% of energy had elevated fasting plasma VLDL concentrations and postprandial TG-rich lipoproteins. These variables did not differ in T allele carriers and noncarriers in the low-PUFA intake group. Moreover, these significant interactions were due exclusively to (n-6) PUFA intake. In summary, high (n-6) PUFA intakes (or = 6.62% of energy intake) were associated with atherogenic dyslipidemia in carriers of the minor T allele at the TCF7L2 rs7903146 SNP and may predispose them to MetS, diabetes, and cardiovascular disease.

Moderate hyperhomocysteinemia is associated with many diseases. Major factors affecting plasma total homocysteine (tHcy) concentrations include folate concentrations and polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene. Because U.S.-mandated fortification of grain products with folic acid has improved folate and tHcy status in Americans, we investigated the effect of the MTHFR 677CT variant before and after fortification. We determined tHcy and folate concentrations in sera from 844 Caucasian and 587 African American participants in the Coronary Artery Risk Development in Young Adults study before and after fortification and we genotyped the MTHFR 677CT variant. MTHFR 677TT homozygotes had higher (P0.01) tHcy concentrations both before and after fortification compared with MTHFR 677CC homozygotes. However, the difference between these 2 genotypes decreased from 2.5 micromol/L before fortification to0.7 micromol/L postfortification (P0.01). In addition, the prevalence of moderate hyperhomocysteinemia (tHcy13 micromol/L) in 677TT homozygotes decreased from 33% before fortification to 12% postfortification (P0.01). Using a cutoff value of 13 micromol/L to define moderate hyperhomocysteinemia, the sensitivity of the MTHFR 677TT genotype to predict elevations in homocysteine was low (approximately 30%) both before and after folic acid fortification. Increasing the cutoff from 13 to 19 micromol/L increased the sensitivity of the assay before fortification to 62% but decreased the sensitivity to 17% postfortification. We conclude that after folic acid fortification in the US, measurement of tHcy rather than genotyping of MTHFR 677TT should be used as the primary assay for the diagnosis and monitoring of moderate hyperhomocysteinemia.

Few studies have adequately considered the type of seafood and background dietary factors when evaluating diet-biomarker and diet-disease associations. The objective of this paper is to evaluate the relationship between different seafood meals and long-chain (n-3) fatty acids [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] biomarkers in the Multi-Ethnic Study of Atherosclerosis (MESA) with white, Chinese-American, black, and Hispanic participants. Dietary intake from a FFQ and plasma phospholipid fatty acids were assessed in 900 MESA participants who were not taking fish oil supplements. When simultaneously adjusting for all seafood groups, concentrations of EPA and DHA in plasma phospholipids were positively correlated with nonfried fish consumption in all 4 ethnic groups (r = 0.24–0.46; P < 0.01) but not with nonfried shellfish, fried fish, or fish in mixed dishes. The magnitude of this correlation was attenuated by up to 67% when type of seafood was not taken into account. After further adjusting for demographic characteristics and other dietary characteristics in multivariate regression models, the association of nonfried fish consumption remained significant (P-trend < 0.001). Data were suggestive of a plateau effect at a nonfried fish intake of about twice weekly. The association of nonfried fish consumption was not modified by intake of (n-6) PUFA or α-linolenic acid. This study highlights the importance of cooking methods (nonfried vs. fried fish), types of seafood (fish vs. shellfish), and the overall seafood consumption when assessing health effects of long-chain (n-3) fatty acids of seafood consumption.

Smoking is associated with increased postprandial hypertriglyceridemia (PPT). Inflammation and insulin resistance are potential "drivers" for this phenomenon. We tested whether inflammatory patterns and/or insulin resistance explain the effect of smoking on PPT.Men and women in the NHLBI Genetics of Lipid-Lowering Drugs and Diet Network (GOLDN) study (n=1036, age 49+/-16y) were included. Each participant was asked to suspend use of lipid-lowering drugs for 3 weeks and was given a high-fat milkshake (83% fat and 700kcal/m(2)). Triglyceride concentrations at 0, 3.5 and 6h after the fat load were measured. Inflammatory markers were measured at baseline. Principal component analysis was used to derive inflammatory patterns from individual inflammatory markers (hsCRP, IL2 soluble receptor-alpha, IL6, TNF-alpha and MCP1). Insulin resistance (IR) was estimated using the HOMA equation. Repeated measures-ANOVA was used for analyses. Two inflammatory patterns, namely CRP-IL6 pattern and MCP1-TNF-alpha pattern, were derived. We found significant main (smoking and time) and interaction (smokingxtime) effects (P0.01) for triglycerides. The multivariate-adjusted triglyceride (mg/dL) concentrations (mean+/-S.E.M.) for never, past and current smokers were 127.38+/-1.04, 119.82+/-1.05 and 134.92+/-1.08 at 0h; 229.42+/-1.04, 238.39+/-1.05 and 293.94+/-1.08 at 3.5h; and 194.63+/-1.04, 208.38+/-1.05 and 248.27+/-1.08 at 6h after the fat load, respectively. Smoking remained significant after adjusting for HOMA-IR and/or inflammatory patterns which showed independent associations with PPT (P0.05).These data confirm impaired metabolism of fat among smokers and suggest that mechanisms other than inflammation or insulin resistance may explain the observed hypertriglyceridemia among smokers.

Many genetic loci affect circulating lipid levels, but it remains unknown whether lifestyle factors, such as physical activity, modify these genetic effects. To identify lipid loci interacting with physical activity, we performed genome-wide analyses of circulating HDL cholesterol, LDL cholesterol, and triglyceride levels in up to 120,979 individuals of European, African, Asian, Hispanic, and Brazilian ancestry, with follow-up of suggestive associations in an additional 131,012 individuals. We find four loci, in/near CLASP1, LHX1, SNTA1, and CNTNAP2, that are associated with circulating lipid levels through interaction with physical activity; higher levels of physical activity enhance the HDL cholesterol-increasing effects of the CLASP1, LHX1, and SNTA1 loci and attenuate the LDL cholesterol-increasing effect of the CNTNAP2 locus. The CLASP1, LHX1, and SNTA1 regions harbor genes linked to muscle function and lipid metabolism. Our results elucidate the role of physical activity interactions in the genetic contribution to blood lipid levels.