Association of apolipoprotein B and nuclear magnetic resonance spectroscopy-derived LDL particle number with outcomes in 25 clinical studies: assessment by the AACC Lipoprotein and Vascular Diseases Division Working Group on Best Practices.

Background: The number of circulating LDL particles is a strong indicator of future cardiovascular disease (CVD) events, even superior to the concentration of LDL cholesterol. Atherogenic (primarily LDL) particle number is typically determined either directly by the serum concentration of apolipoprotein B (apo B) or indirectly by nuclear magnetic resonance (NMR) spectroscopy of serum to obtain NMR-derived LDL particle number (LDL-P).

Content: To assess the comparability of apo B and LDL-P, we reviewed 25 clinical studies containing 85 outcomes for which both biomarkers were determined.

High-density lipoprotein cholesterol efflux, nitration of apolipoprotein A-I, and endothelial function in obese women.

Subjects at risk of atherosclerosis might have dysfunctional high-density lipoprotein (HDL) despite normal cholesterol content in the plasma. We considered whether the efflux of excess cellular cholesterol to HDL from obese subjects is associated with impaired arterial endothelial function, a biomarker of cardiovascular risk. A total of 54 overweight (body mass index [BMI] 25 to 29.

Genetic variation in liver X receptor alpha and risk of ischemic vascular disease in the general population.

Objective: Although animal studies indicate that liver X receptor alpha (LXRα) might influence risk of atherosclerosis, data in humans remain scarce. We tested the hypothesis that genetic variation in LXRα associates with risk of ischemic vascular disease and/or plasma lipid and lipoprotein levels in the general population.

Methods And Results: We studied 10,281 white persons of Danish ancestry from a general population cohort, including 1,986 in whom ischemic heart disease (IHD) developed, and 989 in whom ischemic cerebrovascular disease developed.

S1P, dihydro-S1P and C24:1-ceramide levels in the HDL-containing fraction of serum inversely correlate with occurrence of ischemic heart disease.

Background: The lysosphingolipid sphingosine 1-phosphate (S1P) is carried in the blood in association with lipoproteins, predominantly high density lipoproteins (HDL). Emerging evidence suggests that many of the effects of HDL on cardiovascular function may be attributable to its S1P cargo.

Methods: Here we have evaluated how levels of S1P and related sphingolipids in an HDL-containing fraction of human serum correlate with occurrence of ischemic heart disease (IHD).

High pre-beta1 HDL concentrations and low lecithin: cholesterol acyltransferase activities are strong positive risk markers for ischemic heart disease and independent of HDL-cholesterol.

Background: We hypothesized that patients with high HDL-cholesterol (HDL-C) and ischemic heart disease (IHD) may have dysfunctional HDL or unrecognized nonconventional risk factors.

Methods: Individuals with IHD (Copenhagen University Hospital) and either high HDL-C (n = 53; women >or=735 mg/L; men >or=619 mg/L) or low HDL-C (n = 42; women View Article and Find Full Text PDF

Structure/function relationships of apolipoprotein a-I mimetic peptides: implications for antiatherogenic activities of high-density lipoprotein.

Rationale: Apolipoprotein (apoA)-I mimetic peptides are a promising type of anti-atherosclerosis therapy, but how the structural features of these peptides relate to the multiple antiatherogenic functions of HDL is poorly understood.

Objective: To establish structure/function relationships of apoA-I mimetic peptides with their antiatherogenic functions.

Methods And Results: Twenty-two bihelical apoA-I mimetic peptides were investigated in vitro for the capacity and specificity of cholesterol efflux, inhibition of inflammatory response of monocytes and endothelial cells, and inhibition of low-density lipoprotein (LDL) oxidation.

Effect of ACE insertion/deletion and 12 other polymorphisms on clinical outcomes and response to treatment in the LIFE study.

Objective: This pharmacogenetics substudy from the Losartan Intervention for Endpoint reduction in Hypertension study in patients with hypertension and left ventricular hypertrophy (LVH) treated with the angiotensin receptor blocker losartan versus the beta-blocker atenolol for 4.8 years tested whether the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and 12 other previously well-characterized polymorphisms of hypertension susceptibility genes affected blood pressure reduction, heart rate reduction, cardiovascular events, and/or response to treatment. These polymorphisms were chosen because they could affect blood pressure control or the pharmacological action of losartan or atenolol.

Lecithin: cholesterol acyltransferase--from biochemistry to role in cardiovascular disease.

Purpose Of Review: We discuss the latest findings on the biochemistry of lecithin : cholesterol acyltransferase (LCAT), the effect of LCAT on atherosclerosis, clinical features of LCAT deficiency, and the impact of LCAT on cardiovascular disease from human studies.

Recent Findings: Although there has been much recent progress in the biochemistry of LCAT and its effect on high-density lipoprotein metabolism, its role in the pathogenesis of atherosclerosis is still not fully understood. Studies from various animal models have revealed a complex interaction between LCAT and atherosclerosis that may be modified by diet and by other proteins that modify lipoproteins.

Apolipoprotein B and cardiovascular disease risk: position statement from the AACC Lipoproteins and Vascular Diseases Division Working Group on Best Practices.

Background: Low-density lipoprotein cholesterol (LDL-C) has been the cornerstone measurement for assessing cardiovascular risk for nearly 20 years.

Content: Recent data demonstrate that apolipoprotein B (apo B) is a better measure of circulating LDL particle number (LDL-P) concentration and is a more reliable indicator of risk than LDL-C, and there is growing support for the idea that addition of apo B measurement to the routine lipid panel for assessing and monitoring patients at risk for cardiovascular disease (CVD) would enhance patient management. In this report, we review the studies of apo B and LDL-P reported to date, discuss potential advantages of their measurement over that of LDL-C, and present information related to standardization.

Asymmetry in the lipid affinity of bihelical amphipathic peptides. A structural determinant for the specificity of ABCA1-dependent cholesterol efflux by peptides.

ApoA-I contains a tandem array of amphipathic helices with varying lipid affinity, which are critical in its ability to bind and remove lipids from cells by the ABCA1 transporter. In this study, the effect of asymmetry in the lipid affinity of amphipathic helices in a bihelical apoA-I mimetic peptide, 37pA, on lipid efflux by the ABCA1 transporter was examined. Seven peptide variants of 37pA were produced by substituting a varying number of hydrophobic amino acids for alanine on either one or both helices.

Association of loss-of-function mutations in the ABCA1 gene with high-density lipoprotein cholesterol levels and risk of ischemic heart disease.

Context: Low levels of high-density lipoprotein (HDL) cholesterol are inversely related to cardiovascular risk. Whether this is a causal effect is unclear.

Objective: To determine whether genetically reduced HDL cholesterol due to heterozygosity for 4 loss-of-function mutations in ABCA1 cause increased risk of ischemic heart disease (IHD).

Angiotensinogen and ACE gene polymorphisms and risk of atrial fibrillation in the general population.

Objectives: The renin-angiotensin system may play a role in the pathogenesis of atrial fibrillation, and renin-angiotensin system blockers reduce the risk of atrial fibrillation. We hypothesized that polymorphisms in the angiotensinogen and angiotensin-converting enzyme (ACE) genes encoding proteins in this system predict risk of atrial fibrillation.

Methods And Results: We genotyped 9235 individuals from the Danish general population, The Copenhagen City Heart Study, for the a-20c, g-6a, T174M, and M235T polymorphisms in the angiotensinogen gene and the insertion/deletion (I/D) polymorphism in the ACE gene; rare allele frequencies were 0.

Genetic variation and activity of the renin-angiotensin system and severe hypoglycemia in type 1 diabetes.

Background: The deletion-allele of the angiotensin-converting enzyme (ACE) gene and elevated ACE activity are associated with increased risk of severe hypoglycemia in type 1 diabetes. We explored whether genetic and phenotypic variations in other components of the renin-angiotensin system are similarly associated.

Methods: Episodes of severe hypoglycemia were recorded in 171 consecutive type 1 diabetic outpatients during a 1-year follow-up.

Apolipoprotein AI mimetic peptides: possible new agents for the treatment of atherosclerosis.

There is increasing evidence that therapeutic agents for raising HDL would be a useful addition to the current treatment approach for preventing coronary heart disease (CHD), especially considering the fact that therapies for lowering LDLs are not fully adequate for preventing CHD. The recent unraveling of some of the complexities of HDL metabolism has led to the identification of new key proteins involved in HDL metabolism, thus giving new hope and ideas for drug targets. This review focuses on apolipoprotein AI mimetic peptides, which are currently being explored as therapeutic agents for a new treatment strategy known as acute HDL therapy.

164Ile allele in the beta2-Adrenergic receptor gene is associated with risk of elevated blood pressure in women. The Copenhagen City Heart Study.

Objective: Since beta2-adrenergic receptors are important regulators of blood pressure, genetic variation in this receptor could explain risk of elevated blood pressure in selected individuals. We tested the hypothesis that Gly16Arg, Gln27Glu, and Thr164Ile in the beta2-adrenergic receptor gene associated with elevated blood pressure.

Methods: We genotyped 9185 individuals from the adult Danish general population.

Angiotensinogen gene polymorphism, plasma angiotensinogen, and risk of hypertension and ischemic heart disease: a meta-analysis.

Objective: The aim of this study was to investigate whether the M235T polymorphism in the angiotensinogen gene was associated with angiotensinogen levels, systolic and diastolic blood pressure, hypertension, and risk of ischemic cardiovascular disease in different ethnic populations.

Methods And Results: One hundred twenty-seven studies published between January 1992 and March 2002 examining the association of angiotensinogen gene polymorphisms with the above-mentioned end points were selected. Pooled effect sizes and Mantel-Haenszel odds ratios were calculated using Review Manager.

Angiotensinogen single nucleotide polymorphisms, elevated blood pressure, and risk of cardiovascular disease.

In this study of 10 690 individuals, associations with elevated blood pressure, ischemic heart disease, and ischemic cerebrovascular disease were determined for two noncoding [A(-20)C, G(-6)A] and two coding (T174M, M235T) single nucleotide polymorphisms, analyzed alone and in combination (haplotypes). Participants from the general population with (n=4950) and without (n=4234) elevated blood pressure were compared (study 1), as were participants from the general population without ischemic heart disease and ischemic cerebrovascular disease (n=7965) and cases with either ischemic heart disease (n=1850, study 2) or ischemic cerebrovascular disease (n=848, study 3). Finally, 22-year follow-up of 9184 individuals from the general population examined risk of ischemic heart disease (study 4) and ischemic cerebrovascular disease (study 5).