Lipoprotein Subclasses Research Articles

Sex differences in postprandial responses to different dairy products on lipoprotein subclasses: a randomised controlled cross-over trial.

Men have earlier first-time event of CHD and higher postprandial TAG response compared with women. The aim of this exploratory sub-study was to investigate if intake of meals with the same amount of fat from different dairy products affects postprandial lipoprotein subclasses differently in healthy women and men. A total of thirty-three women and fourteen men were recruited to a randomised controlled cross-over study with four dairy meals consisting of butter, cheese, whipped cream or sour cream, corresponding to 45 g of fat (approximately 60 energy percent). Blood samples were taken at 0, 2, 4 and 6 h postprandially. Lipoprotein subclasses were measured using NMR and analysed using a linear mixed model. Sex had a significant impact on the response in M-VLDL (P=0·04), S-LDL (P=0·05), XL-HDL (P=0·009) and L-HDL (P=0·001) particle concentration (P), with women having an overall smaller increase in M-VLDL-P, a larger decrease in S-LDL-P and a larger increase in XL- and L-HDL-P compared with men, independent of meal. Men showed a decrease in XS-VLDL-P compared with women after intake of sour cream (P<0·01). In men only, XS-VLDL-P decreased after intake of sour cream compared with all other meals (v. butter: P=0·001; v. cheese: P=0·04; v. whipped cream: P=0·006). Meals with the same amount of fat from different dairy products induce different postprandial effects on lipoprotein subclass concentrations in men and women.

Associations of physical activity and sedentary time with lipoprotein subclasses in Norwegian schoolchildren: The Active Smarter Kids (ASK) study

Background and aimsPhysical activity is favourably associated with certain markers of lipid metabolism. The relationship of physical activity with lipoprotein particle profiles in children is not known. Here we examine cross-sectional associations between objectively measured physical activity and sedentary time with serum markers of lipoprotein metabolism. MethodsOur cohort included 880 children (49.0% girls, mean age 10.2 years). Physical activity intensity and time spent sedentary were measured objectively using accelerometers. 30 measures of lipoprotein metabolism were quantified using nuclear magnetic resonance spectroscopy. Multiple linear regression models adjusted for age, sex, sexual maturity and socioeconomic status were used to determine associations of physical activity and sedentary time with lipoprotein measures. Additional models were adjusted for adiposity. Isotemporal substitution models quantified theoretical associations of replacing 30 min of sedentary time with 30 min of moderate- to vigorous-intensity physical activity (MVPA). ResultsTime spent in MVPA was associated with a favourable lipoprotein profile independent of sedentary time. There were inverse associations with a number of lipoprotein measures, including most apolipoprotein B-containing lipoprotein subclasses and triglyceride measures, the ratio of total to high-density lipoprotein (HDL) cholesterol, and non-HDL cholesterol concentration. There were positive associations with larger HDL subclasses, HDL cholesterol concentration and particle size. Reallocating 30 min of sedentary time to MVPA had broadly similar associations. Sedentary time was only partly and weakly associated with an unfavourable lipoprotein profile. ConclusionsPhysical activity of at least moderate-intensity is associated with a favourable lipoprotein profile in schoolchildren, independent of time spent sedentary, adiposity and other confounders.

The Differential Effects Of Amount, Intensity, And Mode Of Exercise Training On A Novel Lipoprotein Multimarker Of Insulin Resistance

PURPOSE: To examine the effects of amount, intensity, and mode of exercise training on Lipoprotein Insulin Resistance Index (LP-IR; a relatively new spectroscopic multimarker of insulin resistance) across 10 exercise interventions from the STRRIDE studies. METHODS: A total of 531 men and women with dyslipidemia [STRRIDE I (n=222) and STRRIDE AT/RT (n=142)] or prediabetes [STRRIDE-PD (n=167)] were randomized to either control group or one of 10 exercise interventions, which ranged from doses of 8-22 kcal/kg/week (KKW); intensities of 50-75% V̇O2peak; and durations of 6-9 months. Two groups included resistance training and one group included dietary intervention (weight loss goal of 7%). Fasting blood samples were obtained at both baseline and 16-24 hr after the final exercise bout. NMR spectroscopy was performed at LabCorp to determine LP-IR score, which is comprised of six lipoprotein subclass and size parameters. LP-IR score ranges from 0 (most insulin sensitive) to 100 (most insulin resistant). Paired t-tests determined post- minus pre-intervention change score significance within groups (p<0.05). Study-specific ANCOVA determined differences between groups. RESULTS: The inactive control group did not significantly change LP-IR. After training, seven of the 10 exercise groups significantly improved LP-IR, ranging from -4.0 ± 7.6 to -12.5 ± 14.2. The figure displays change scores across all groups. The Aerobic plus Resistance group resulted in significantly greater change than the Resistance only group in STRRIDE AT/RT. The Moderate plus Diet group had significantly greater LP-IR change than all other groups in STRRIDE-PD. CONCLUSION: On average, STRRIDE interventions improved LP-IR. Our results provide compelling evidence that adding resistance to aerobic training elicits a synergistic training effect on LP-IR. In individuals with prediabetes, incorporating dietary intervention with aerobic training results in the most robust LP-IR improvement.

41-LB: Lipoprotein Subfractions Are Associated with Diabetic Microvascular Disease among 9,795 Patients in the FIELD Trial

Background: In the FIELD trial, a 5-year randomized double-blind placebo-controlled trial of fenofibrate vs. placebo in 9,795 adults with type 2 diabetes (T2D), the only standard lipid parameter correlating with microvascular (renal) events was triglycerides. Given the high prevalence of diabetic microangiopathy, we explored associations between lipoprotein subfractions and nephropathy, retinopathy, microvascular amputations (MiAmp) and neuropathy. Methods: We performed ultracentrifugation using the vertical autoprofile (VAP, Atherotech) on plasma (baseline and after 6 weeks of fenofibrate). Analyses were performed using Cox proportional hazards and logistic regression for new on-study events. Results were adjusted for gender and fenofibrate or placebo allocation. Results: HDL related analytes (HDL-C, HDL3-C, apo A1, apoA2) correlated with reduced risk for neuropathy, nephropathy, and MiAmp. Buoyant LDL (LDL1-C) and densest LDL (LDL4-C) correlated negatively with neuropathy and positively for MiAmp, respectively. Triglycerides and apo C3 increased neuropathy and nephropathy risk. VLDL species correlated with increased MiAmp and retinopathy risk. Conclusions: VAP identifies multiple lipoprotein subclasses and VAP subclass/apoprotein ratios associated with diabetic microangiopathy. Many were improved with fenofibrate. Disclosure P.P. Toth: Consultant; Self; Amarin Corporation, Amgen Inc., AstraZeneca, Kowa Pharmaceutical Europe Co. Ltd., Novo Nordisk Inc. Speaker’s Bureau; Self; Amarin Corporation, Amgen Inc., Merck &amp; Co., Inc., Novo Nordisk Inc., Regeneron Pharmaceuticals, Sanofi US. A.C. Keech: None. A.S. Januszewski: None. R.L. OConnell: None. L. Li: None. D. Sullivan: None. M. Taskinen: Advisory Panel; Self; Novo Nordisk A/S. Consultant; Self; Akcea Therapeutics, Chiesi USA, Inc. Research Support; Self; Amgen Inc., Novo Nordisk A/S. Speaker’s Bureau; Self; Amgen Inc. P.L. Drury: None. G.F. Watts: None. J.D. Best: Consultant; Self; Abbott. J. Ansquer: Research Support; Self; Abbott, Mylan. S.R. Jones: None. A.J. Jenkins: Advisory Panel; Self; Abbott, Australian Diabetes Society, Medtronic. Research Support; Self; Abbott, GlySens Incorporated, Medtronic, Mylan. Speaker’s Bureau; Self; Eli Lilly and Company, Novo Nordisk Inc.

23-LB: Lipoprotein Subfractions Are Associated with Diabetic Cardiovascular Disease and Death among 9,795 Patients in the FIELD Trial

Background: The FIELD study, a 5-year randomized double-blind placebo-controlled trial of fenofibrate vs. placebo in 9,795 adults with type 2 diabetes (T2D), was designed to evaluate effects on coronary and cardiovascular (CV) events. In this analysis we explored associations between lipoprotein subfractions and on-study CV events and death. Methods: We performed ultracentrifugation using the vertical auto profile (VAP, Atherotech) on plasma at baseline and after 6 weeks of fenofibrate (active run-in) exposure. Analyses were performed using Cox proportional hazards and logistic regression analysis. Results were adjusted for gender, with log transformation as necessary. Results: Total CVD and CV death correlated negatively with HDL-C and its subfractions, as well as apoA1 and apoA2. In addition to LDL-C, small, dense LDL (LDL4-C), non-HDL-C, apo B, triglycerides, and apoC3 increased risk for total CVD. For CVD death, HDL-C and its subfractions were protective, while apo B, triglycerides, apo C3, and various VLDL-C species were associated with increased risk. Conclusions: Detailed lipoprotein analysis identifies multiple lipoprotein subclasses and apolipoproteins and their ratios associated with acute cardiovascular events and death. Serum levels of a number of these lipoprotein and apoprotein species were improved by fenofibrate therapy. Disclosure S.R. Jones: None. A.J. Jenkins: Advisory Panel; Self; Abbott, Australian Diabetes Society, Medtronic. Research Support; Self; Abbott, GlySens Incorporated, Medtronic, Mylan. Speaker’s Bureau; Self; Eli Lilly and Company, Novo Nordisk Inc. A.S. Januszewski: None. R.L. OConnell: None. L. Li: None. D. Sullivan: None. M. Taskinen: Advisory Panel; Self; Novo Nordisk A/S. Consultant; Self; Akcea Therapeutics, Chiesi USA, Inc. Research Support; Self; Amgen Inc., Novo Nordisk A/S. Speaker’s Bureau; Self; Amgen Inc. R. Scott: None. G.F. Watts: None. P.J. Barter: Advisory Panel; Self; Merck &amp; Co., Inc., Pfizer Inc. R. Simes: None. P.P. Toth: Consultant; Self; Amarin Corporation, Amgen Inc., AstraZeneca, Kowa Pharmaceutical Europe Co. Ltd., Novo Nordisk Inc. Speaker’s Bureau; Self; Amarin Corporation, Amgen Inc., Merck &amp; Co., Inc., Novo Nordisk Inc., Regeneron Pharmaceuticals, Sanofi US. A.C. Keech: None.

A third of nonfasting plasma cholesterol is in remnant lipoproteins: Lipoprotein subclass profiling in 9293 individuals

Background and aimsIncreased concentrations of calculated remnant cholesterol in triglyceride-rich lipoproteins are observationally and genetically, causally associated with increased risk of ischemic heart disease; however, when measured directly, the fraction of plasma cholesterol present in remnant particles is unclear. We tested the hypothesis that a major fraction of plasma cholesterol is present in remnant lipoproteins in individuals in the general population. MethodsWe examined 9293 individuals from the Copenhagen General Population Study using nuclear magnetic resonance spectroscopy measurements of total cholesterol, free- and esterified cholesterol, triglycerides, phospholipids, and particle concentration. Fourteen subclasses of decreasing size and their lipid constituents were analysed: six subclasses were very low-density lipoprotein (VLDL), one intermediate-density lipoprotein (IDL), three low-density lipoprotein (LDL), and four subclasses were high-density lipoprotein (HDL). Remnant lipoproteins were VLDL and IDL combined. ResultsMean nonfasting cholesterol concentration was 1.84 mmol/L (72 mg/dL) for remnants, 2.01 mmol/L (78 mg/dL) for LDL, and 1.83 mmol/L (71 mg/dL) for HDL, equivalent to remnants containing 32% of plasma total cholesterol. Of 14 lipoprotein subclasses, large LDL and IDL were the ones containing most of plasma cholesterol. The plasma concentration of remnant cholesterol was from ∼1.4 mmol/L (54 mg/dL) at age 20 to ∼1.9 mmol/L (74 mg/dL) at age 60. Corresponding values for LDL cholesterol were from ∼1.5 mmol/L (58 mg/dL) to ∼2.1 mmol/L (81 mg/dL). ConclusionsUsing direct measurements, one third of total cholesterol in plasma was present in remnant lipoproteins, that is, in the triglyceride-rich lipoproteins IDL and VLDL.

CETP genotype and concentrations of HDL and lipoprotein subclasses in African-American men.

Aim: To assess the association between theCETP Taq1B and I405V polymorphisms with levels of lipoprotein subclasses in African-American (AA) men with and without Type 2diabetes (T2DM). Patients & methods: AA men, over 30 years of age, with (n=54) or without T2DM (n=50), and not receiving lipid-lowering agents, underwent advanced lipid analysis and genotyping. Results & conclusion: In the total patient population Taq1B B2-allele carriers had significantly higher levels of large HDL subclasses (HDL-2b [p=0.017] and HDL-L [p=0.019]), lower levels of small-HDL subclasses (HDL-3a [p =0.004] and HDL-3b [p=0.031]), and lower levels of LDL subclasses (LDL-IVa [p=0.012] and LDL-IIIb [p=0.009]). The only significant genotype-diabetes interaction occurred with the HDL-2a subclass (p=0.015). No statistically significant associations were seen with I405V genotype. Our observations of lower levels of small-HDL and higher levels of large-HDL suggest that a potentially important HDL subclass-CETP relationship exists.

Using metabolic profiling and gene expression analyses to explore molecular effects of replacing saturated fat with polyunsaturated fat—a randomized controlled dietary intervention study

ABSTRACTBackgroundReplacing dietary saturated fatty acids (SFAs) with polyunsaturated fatty acids (PUFA) reduces the plasma low-density lipoprotein (LDL) cholesterol and subsequently the risk of cardiovascular disease. However, beyond changes in LDL cholesterol, we lack a complete understanding of the physiologic alterations that occur when improving dietary fat quality.ObjectivesThe aim of this study was to gain knowledge of metabolic alterations paralleling improvements in the fat quality of the diet.MethodsWe recently conducted an 8-wk, double-blind, randomized controlled trial replacing SFAs with PUFAs in healthy subjects with moderate hypercholesterolemia (n = 99). In the present substudy, we performed comprehensive metabolic profiling with multiple platforms (both nuclear magnetic resonance- and mass spectrometry-based technology) (n = 99), and analyzed peripheral blood mononuclear cell gene expression (n = 95) by quantitative real-time polymerase chain reaction.ResultsA large number of lipoprotein subclasses, myristoylcarnitine and palmitoylcarnitine, and kynurenine were reduced when SFAs were replaced with PUFAs. In contrast, bile acids, proprotein convertase subtilisin/kexin type 9, acetate, and acetoacetate were increased by the intervention. Some amino acids were also altered by the intervention. The mRNA levels of LXRA and LDLR were increased, in addition to several liver X receptor α target genes and genes involved in inflammation, whereas the mRNA levels of UCP2 and PPARD were decreased in peripheral blood mononuclear cells after replacing SFAs with PUFAs. Partial least squares-discriminant analysis showed that the 30 most important variables that contributed to class separation spanned all classes of biomarkers, and was in accordance with the univariate analysis.ConclusionsApplying metabolomics in randomized controlled dietary intervention trials has the potential to extend our knowledge of the biological and molecular effects of dietary fat quality. This study was registered at clinicaltrials.gov as NCT 01679496.

Differences in peripheral blood mononuclear cell gene expression and triglyceride composition in lipoprotein subclasses in plasma triglyceride responders and non-responders to omega-3 supplementation

BackgroundIntake of the marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) reduces fasting triglyceride (TG) levels and may thereby lower cardiovascular disease risk. However, there are large inter-individual differences in the TG-lowering effect of omega-3 supplementation. Genotype differences partly explain this variation, but gene-environment interactions leading to gene expression differences may also be important. In this study, we aimed to investigate baseline differences and differences in the change in peripheral blood mononuclear cell (PBMC) gene expression and lipoprotein subclass TG levels between TG responders and non-responders to omega-3 fatty acid supplementation.MethodsIn a previous randomized controlled trial, healthy normotriglyceridemic subjects (n = 35, 71% women) received 1.6 g EPA + DHA/day for 7 weeks. In this exploratory sub-study, we defined TG responders as subjects having a TG reduction beyond the 20% day-to-day variation and non-responders as having a TG change between − 20% and + 20% after omega-3 supplementation. PBMC gene expression was measured using microarray, and lipoprotein subclasses were measured using nuclear magnetic resonance spectroscopy.ResultsEight subjects were defined as responders with a median TG reduction of 37%, and 16 subjects were defined as non-responders with a median TG change of 0%. At baseline, responders had higher TG levels in two of four high-density lipoprotein (HDL) subclasses and 909 gene transcripts (p ≤ 0.05) were differentially expressed compared to non-responders. During the intervention, the plasma TG reduction among responders was reflected in TG reductions in four of six different very low-density lipoprotein subclasses and three of four different HDL subclasses. Compared to non-responders, the expression of 454 transcripts was differentially altered in responders (p ≤ 0.05). Pathway analyses revealed that responders had altered signaling pathways related to development and immune function. In addition, two of the top 10 enriched pathways in responders compared to non-responders were related to lysophosphatidic acid signaling.ConclusionTG responders and non-responders to omega-3 supplementation have different lipoprotein subclass and PBMC gene expression profiles at baseline and different lipoprotein subclass and PBMC gene expression responses to omega-3 supplementation. These gene expression differences may partially explain the variability in TG response observed after omega-3 supplementation.Graphical abstractBased on free images from Servier Medical Art (Creative Commons Attribution License) and image from www.colourbox.com.

Gut Microbial Associations to Plasma Metabolites Linked to Cardiovascular Phenotypes and Risk.

Altered gut microbial composition has been linked to cardiovascular diseases (CVDs), but its functional links to host metabolism and immunity in relation to CVD development remain unclear. To systematically assess functional links between the microbiome and the plasma metabolome, cardiometabolic phenotypes, and CVD risk and to identify diet-microbe-metabolism-immune interactions in well-documented cohorts. We assessed metagenomics-based microbial associations between 231 plasma metabolites and microbial species and pathways in the population-based LLD (Lifelines DEEP) cohort (n=978) and a clinical obesity cohort (n=297). After correcting for age, sex, and body mass index, the gut microbiome could explain ≤11.1% and 16.4% of the variation in plasma metabolites in the population-based and obesity cohorts, respectively. Obese-specific microbial associations were found for lipid compositions in the VLDL, IDL, and LDL lipoprotein subclasses. Bacterial L-methionine biosynthesis and a Ruminococcus species were associated to cardiovascular phenotypes in obese individuals, namely atherosclerosis and liver fat content, respectively. Integration of microbiome-diet-inflammation analysis in relation to metabolic risk score of CVD in the population cohort revealed 48 microbial pathways associated to CVD risk that were largely independent of diet and inflammation. Our data also showed that plasma levels rather than fecal levels of short-chain fatty acids were relevant to inflammation and CVD risk. This study presents the largest metagenome-based association study on plasma metabolism and microbiome relevance to diet, inflammation, CVD risk, and cardiometabolic phenotypes in both population-based and clinical obesity cohorts. Our findings identified novel bacterial species and pathways that associated to specific lipoprotein subclasses and revealed functional links between the gut microbiome and host health that provide a basis for developing microbiome-targeted therapy for disease prevention and treatment.

Metabolomic Signature of Angiopoietin-Like Protein 3 Deficiency in Fasting and Postprandial State.

Objective- Loss-of-function (LOF) variants in the ANGPTL3 (angiopoietin-like protein 3) have been associated with low levels of plasma lipoproteins and decreased coronary artery disease risk. We aimed to determine detailed metabolic effects of genetically induced ANGPTL3 deficiency in fasting and postprandial state. Approach and Results- We studied individuals carrying S17X LOF mutation in ANGPTL3 (6 homozygous and 32 heterozygous carriers) and 38 noncarriers. Nuclear magnetic resonance metabolomics was used to quantify 225 circulating metabolic measures. We compared metabolic differences between LOF carriers and noncarriers in fasting state and after a high-fat meal. In fasting, ANGPTL3 deficiency was characterized by similar extent of reductions in LDL (low-density lipoprotein) cholesterol (0.74 SD units lower concentration per LOF allele [95% CI, 0.42-1.06]) as observed for many TRL (triglyceride-rich lipoprotein) measures, including VLDL (very-low-density lipoprotein) cholesterol (0.75 [95% CI, 0.45-1.05]). Within most lipoprotein subclasses, absolute levels of cholesterol were decreased more than triglycerides, resulting in the relative proportion of cholesterol being reduced within TRLs and their remnants. Further, β-hydroxybutyrate was elevated (0.55 [95% CI, 0.21-0.89]). Homozygous ANGPTL3 LOF carriers showed essentially no postprandial increase in TRLs and fatty acids, without evidence for adverse compensatory metabolic effects. Conclusions- In addition to overall triglyceride- and LDL cholesterol-lowering effects, ANGPTL3 deficiency results in reduction of cholesterol proportion within TRLs and their remnants. Further, ANGPTL3 LOF carriers had elevated ketone body production, suggesting enhanced hepatic fatty acid β-oxidation. The detailed metabolic profile in human knockouts of ANGPTL3 reinforces inactivation of ANGPTL3 as a promising therapeutic target for decreasing cardiovascular risk.

Reduced plasma levels of small HDL particles transporting fibrinolytic proteins in pulmonary arterial hypertension

BackgroundAberrant lipoprotein metabolism has been implicated in experimental pulmonary hypertension, but the relevance to patients with pulmonary arterial hypertension (PAH) is inconclusive.ObjectiveTo investigate the relationship between circulating lipoprotein subclasses and...

Abstract P199: Small HDL-C is Associated to Subclinical Hypothyroidism. The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Introduction: Although epidemiologic studies have associated subclinical thyroid disorders with coronary heart disease, the role of lipoprotein levels are not well defined as a mediator or moderator of this association. Purpose: To test the association of lipoprotein particle concentration and size measured by nuclear magnetic resonance with subclinical hyperthyroidism and subclinical hypothyroidism using baseline data from the Brazilian Longitudinal Study of Health (ELSA-Brasil) of apparently healthy 5024 men and women aged 35 to 74 years old. Methods: We measured lipids and lipoproteins subfractions using a new nuclear magnetic resonance spectroscopy (NMR LipoProfile® test spectra, LabCorp, Raleigh, NC): triglyceride-rich lipoprotein particles (TRLP, containing IDL-P and VLDL-P), 3 LDL-P subclasses (large, medium and small) and 3 HDL-P subclasses (large, medium and small). Subclinical thyroid disorders were defined as TSH &gt;4 IU/ml and TSH &lt;0.4 IU/ml for people with normal free-thyroxine levels. We excluded from the sample participants reporting previous cardiovascular disease, those who used lipid-lowering medications and/or other drugs that interfere with thyroid function remaining 3,947 subjects. The cross-sectional relationship between subclinical thyroid diseases (independent variable) and lipids and lipoproteins (dependent variable) were evaluated by linear regression models using euthyroid subjects as the reference. Models were presented as crude and after adjustment for sociodemographic (age, sex, race, and education), cardiovascular risk factors (body-mass index, hypertension, diabetes, smoking habit, alcohol use, and physical activity) and LDL-C, HDL-C and triglycerides measured by enzymatic methods. Results: After exclusions, we detected 47 persons with subclinical hyperthyroidism (mean age 53.1 (±9.4 years; 61.7% women), 258 with subclinical hypothyroidism (mean age 52.3 (±8.9); 58.1% women) and 3,642 participants with normal thyroid function (mean age: 50.1 (±8.6); 52% women). After multivariate adjustment, subclinical hyperthyroidism was associated with a decrease in triglyceride-rich lipoprotein particles (Beta coefficient (B) -15.2; P=0.04) and with the very small triglyceride-rich lipoprotein subclass (B, -16.9; P=0.04). Subclinical hypothyroidism was associated with a decrease in small HDL-P subclass (B, 0.42; P=0.03). No association was found for any subclinical conditions with LDL-C. Conclusions: Subclinical hyperthyroidism does not show any possible association with an atherogenic profile, and subclinical hypothyroidism revealed an association with lower small HDL-cholesterol levels.

HIV and cardiovascular diseases risk: exploring the interplay between T-cell activation, coagulation, monocyte subsets, and lipid subclass alterations.

Although rollout of combined antiretroviral treatment (cART) has blunted human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) onset, there is increased development of cardiovascular diseases (CVDs) in HIV-infected individuals. While most HIV-infected individuals on cART achieve viral suppression, this may not necessarily result in complete immunological recovery. This study therefore evaluated T-cell-mediated changes and coagulation markers in HIV-positive individuals to ascertain their potential to increase CVD risk. Eighty participants were recruited (Worcester, South Africa), and fasted blood was collected to evaluate: 1) immune activation (CD38 expression on CD4+ and CD8+ T cells) and thrombus formation [tissue factor (CD142)] on CD4+ and CD8+ T cells; 2) monocyte subpopulations (nonclassical, intermediate, and classical); and 3) classical regulatory T (Treg) cells with activation markers [glycoprotein A repetitions predominant (GARP) and special AT-rich sequence-binding protein 1 (SATB-1)]. High- and low-density lipoprotein subclasses (Lipoprint) were also determined. This study revealed four key findings for HIV-positive patients: 1) coexpression of the CD142 coagulation marker together with immune activation on both CD4+ and CD8+ T cells during chronic infection stages; 2) Treg cell activation and upregulated GARP and SATB-1 contributing to Treg dysfunction in chronic HIV; 3) proatherogenic monocyte subset expansion with significant correlation between T-cell activation and macrophage activation (marker: CD163); and 4) significant correlation between immune activation and lipid subclasses, revealing crucial changes that can be missed by traditional lipid marker assessments (LDL and HDL). These data also implicate lipopolysaccharide-binding protein as a crucial link between immune activation, lipid alterations, and increased CVD risk. NEW & NOTEWORTHY With combined antiretroviral treatment rollout, HIV-AIDS patients are increasingly associated with cardiovascular diseases onset. This study demonstrated the significant interplay between adaptive immune cell activation and monocyte/macrophage markers in especially HIV-positive individuals with virological failure and on second line treatment. Our data also show a unique link between immune activation and lipid subclass alterations, revealing important changes that can be missed by traditional lipid marker assessments (e.g., LDL and HDL).

HDL Subclass Distribution Shifts with Increasing Central Adiposity.

Although cross-sectional studies have shown that obesity is associated with lower concentrations of large high-density lipoprotein (HDL) subclasses, it is unknown if changes in HDL subclasses are related to changes in body fat and its distribution over time. We therefore assessed changes in HDL subclass distribution over a 5.5-year free-living follow-up period in 24 black South African women. At baseline and follow-up, body composition and body fat distribution were measured using anthropometry, dual X-ray absorptiometry, and computerized tomography. HDL subclass distribution was quantified using Lipoprint®. Over the 5.5-year follow-up period, body fat (+17.3 ± 4.5 kg, p < 0.05) and trunk fat mass (+7.4 ± 1.9%, % fat mass, FM, p < 0.05) increased, while leg fat mass (−2.53 ± 0.56%, % FM, p < 0.001) and the distribution of large (−6.43 ± 2.12%, p < 0.05) HDL subclasses decreased. A percentage decrease in large HDL subclasses was associated with a percentage increase in central fat mass (visceral adipose tissue (VAT) area, p < 0.05) and a percentage decrease in peripheral fat mass (leg fat mass). These preliminary findings suggest that a relative redistribution of body fat from the periphery to the abdominal region were associated with a decrease HDL subclass size in black South African women and provide a novel link between body fat distribution and lipidology in this population.

The Role of Lipids in Parkinson's Disease.

Parkinson’s disease (PD) is a neurodegenerative disease characterized by a progressive loss of dopaminergic neurons from the nigrostriatal pathway, formation of Lewy bodies, and microgliosis. During the past decades multiple cellular pathways have been associated with PD pathology (i.e., oxidative stress, endosomal-lysosomal dysfunction, endoplasmic reticulum stress, and immune response), yet disease-modifying treatments are not available. We have recently used genetic data from familial and sporadic cases in an unbiased approach to build a molecular landscape for PD, revealing lipids as central players in this disease. Here we extensively review the current knowledge concerning the involvement of various subclasses of fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, and lipoproteins in PD pathogenesis. Our review corroborates a central role for most lipid classes, but the available information is fragmented, not always reproducible, and sometimes differs by sex, age or PD etiology of the patients. This hinders drawing firm conclusions about causal or associative effects of dietary lipids or defects in specific steps of lipid metabolism in PD. Future technological advances in lipidomics and additional systematic studies on lipid species from PD patient material may improve this situation and lead to a better appreciation of the significance of lipids for this devastating disease.

PON1 concentration and high-density lipoprotein characteristics as cardiovascular biomarkers.

IntroductionSerum paraoxonase 1 (PON1) is now known to be related to cardiovascular diseases (CVD). The aim of this study was to determine the relationship between PON1 concentration and high-density lipoprotein (HDL) subclasses in patients with proven CVD, cardiovascular risk factors but no CVD (CRF), and in healthy controls (control group).Material and methodsA case-control study was carried out with 69 volunteers from the Mexican Institute of Social Security, Mexico. Clinical parameters, lipid profile, PON1 concentration, PON1 activities (AREase and CMPAase), and HDL subclasses were evaluated.ResultsPatients with CVD had significantly higher glucose and lower total cholesterol than the control group had (p < 0.01). AREase activity was not different between the control (122.57 ±30.72 U/ml), CRF (115.81 ±32.81 U/ml), and CVD (109.34 ±29.60 U/ml) groups. PON1 concentration was significantly lower in CVD patients than in CRF and control patients (p < 0.001); a positive correlation was observed between AREase activity and PON1 concentration in the CVD group (Rho = 0.58; p < 0.01). Logistic regression analysis showed that the decrease in PON1 level was associated with the CVD group (RRR = 0.20; 95% CI: 0.09–0.45) but not with the CRF group (RRR = 1.29; 95% CI: 0.89–1.90). Significant differences were observed in HDL 2a and HDL 3a concentrations between the control group and CRF and CVD groups (p < 0.05), but not between the CRF and CVD groups.ConclusionsOur data suggest that PON1 status and HDL characteristics could be early biomarkers that predict the potential for developing CVD.

Small HDL subclass is associated with coronary plaque stability: An optical coherence tomography study in patients with coronary artery disease

The role of high-density lipoprotein (HDL) subclasses in atherosclerotic diseases remains an open question. Previous clinical trials have attempted to explore the predictive effect of HDL subspecies on cardiovascular risk. However, no studies have assessed the connections between these subclasses and characteristics of plaque microstructure. To investigate the relationship of HDL subclasses and coronary plaque stability assessed by optical coherence tomography (OCT). Morphological characteristics of 160 nontarget lesions from 85 patients with coronary artery disease were assessed by OCT. HDL subclass profiles were analyzed using nondenaturing polyacrylamide gel electrophoresis. The plasma levels of small HDL subclass (percentage or concentration) were found to be positively associated with fibrous cap thickness (r=0.232, P=.007; r=0.243, P=.005) and negatively with maximum lipid arc (r=-0.240, P=.005; r=-0.252, P=.003) and lipid core length (r=-0.350, P<.001; r=-0.367, P<.001). Multivariate logistic regression analysis showed the small HDL subclass (percentage or concentration) (odds ratio [OR]: 0.457, 95% confidence interval [CI]: 0.214-0.974, P=.043; OR: 0.438, 95% CI: 0.204-0.938, P=.034) to be an independent factor in predicting OCT-detected thin-cap fibroatheroma of nontarget lesions. High levels of small HDL are associated with coronary nontarget plaque stability. Our findings suggest that the small HDL subtype might represent the atheroprotective activity of HDL.

Ezetimibe in Combination With Simvastatin Reduces Remnant Cholesterol Without Affecting Biliary Lipid Concentrations in Gallstone Patients.

BackgroundIn randomized trials (SHARP [Study of Heart and Renal Protection], IMPROVE‐IT [Improved Reduction of Outcomes: Vytorin Efficacy International Trial]), combination of statin and ezetimibe resulted in additional reduction of cardiovascular events. The reduction was greater in patients with type 2 diabetes mellitus (T2DM), where elevated remnant cholesterol and high cardiovascular disease risk is characteristic. To evaluate possible causes behind these results, 40 patients eligible for cholecystectomy, randomized to simvastatin, ezetimibe, combined treatment (simvastatin+ezetimibe), or placebo treatment during 4 weeks before surgery, were studied.Methods and ResultsFasting blood samples were taken before treatment start and at the end (just before surgery). Bile samples and liver biopsies were collected during surgery. Hepatic gene expression levels were assessed with qPCR. Lipoprotein, apolipoprotein levels, and content of cholesterol, cholesteryl ester, and triglycerides were measured after lipoprotein fractionation. Lipoprotein subclasses were analyzed by nuclear magnetic resonance. Apolipoprotein affinity for human arterial proteoglycans (PG) was measured. Biomarkers of cholesterol biosynthesis and intestinal absorption and bile lipid composition were analyzed using mass spectrometry. Combined treatment caused a statistically significant decrease in plasma remnant particles and apolipoprotein B (ApoB)/lipoprotein content of cholesterol, cholesteryl esters, and triglycerides. All treatments reduced ApoB‐lipoprotein PG binding. Simvastatin and combined treatment modified the composition of lipoproteins. Changes in biomarkers of cholesterol synthesis and absorption and bile acid synthesis were as expected. No adverse events were found.ConclusionsCombined treatment caused atheroprotective changes on ApoB‐lipoproteins, remnant particles, bile components, and in ApoB‐lipoprotein affinity for arterial PG. These effects might explain the decrease of cardiovascular events seen in the SHARP and IMPROVE‐IT trials.Clinical Trial Registration URL: www.clinicaltrialsregister.eu. Unique identifier: 2006‐004839‐30).

A Biomimetic Lipid Membrane Device Reveals the Interaction of Cancer Biomarkers with Human Serum Lipidic Moieties.

A major problem for the detection of cancer biomarkers in plasma or serum is that common clinical practice does not require the patient to be in a fasting state. Considering that lipoproteins are the main population affected by food intake, the authors hypothesized that biomarkers could be embedded in lipid particles and thereby opens a new avenue for detection. Using the recently published biomarker, soluble VE-cadherin (sVE), the authors tested our hypothesis using techniques of biophysics, biochemistry and the tools of nanobiotechnology on serum samples from kidney cancer patients (n = 106). Optical density as well as contact angle measurements of serum revealed heterogeneity in the particle content of the serum samples. Isolation of the lipidic moieties by ultracentrifugation showed that sVE was detected in this compartment. Further, isolation of lipoprotein subclasses by precipitation with sodium phosphotungstate and MgCl2 , showed that HDL carried the majority of sVE. Immunoprecipitation of sVE confirmed that it was associated with Apolipoprotein A1, a major compound of HDL. Using a biomimetic lipid bilayer membrane coupled with impedance spectroscopy the authors quantified, in real-time, that the sVE adsorbed to the lipid bilayer membrane without altering its structure. Taken together, these results show for the first time a direct interaction of a cancer biomarker with lipids. The authors anticipate these results to prompt fasting for future blood tests for large-scale studies in the biomarkers research field.