Lipoprotein Particle Subclasses Research Articles

The Nutri-Score nutrition label: Associations between the underlying nutritional profile of foods and lipoprotein particle subclass profiles in adults

Background and aimsLipoprotein particle concentrations and size are associated with increased risk for atherosclerosis and premature cardiovascular disease. Certain dietary behaviours may be cardioprotective and public health strategies are needed to guide consumers’ dietary choices and help prevent diet-related disease. The Food Standards Agency nutrient profiling system (FSAm-NPS) constitutes the basis of the five-colour front-of-pack Nutri-Score labelling system. No study has examined FSAm-NPS index associations with a wide range of lipoprotein particle subclasses. MethodsThis was a cross-sectional study of 2006 middle-to older-aged men and women randomly selected from a large primary care centre. Individual participant FSAm-NPS dietary scores were derived from validated food frequency questionnaires. Lipoprotein particle subclass concentrations and size were determined using nuclear magnetic resonance spectroscopy. Multivariate-adjusted linear regression analyses were performed to examine FSAm-NPS relationships with lipoprotein particle subclasses. ResultsIn fully adjusted models which accounted for multiple testing, higher FSAm-NPS scores, indicating poorer dietary quality, were positively associated with intermediate-density lipoprotein (β = 0.096, p = 0.005) and small high-density lipoprotein (HDL) (β = 0.492, p = 0.006) concentrations, a lipoprotein insulin resistance score (β = 0.063, p = 0.02), reflecting greater lipoprotein-related insulin resistance, and inversely associated with HDL size (β = −0.030, p = 0.045). ConclusionsA higher FSAm-NPS score is associated with a less favourable lipoprotein particle subclass profile in middle-to older-aged adults which may be a potential mechanism underlying reported health benefits of a healthy diet according to Nutri-Score rating.

Missense variants in SORT1 are associated with LDL-C in an Amish population

Common noncoding variants at the human 1p13.3 locus associated with SORT1 expression are among those most strongly associated with low-density lipoprotein cholesterol (LDL-C) in human genome-wide association studies. However, validation studies in mice and cell lines have produced variable results regarding the directionality of the effect of SORT1 on LDL-C. This, together with the fact that the 1p13.3 variants are associated with expression of several genes, has raised the question of whether SORT1 is the causal gene at this locus. Using whole exome sequencing in members of an Amish population, we identified coding variants in SORT1 that are associated with increased (rs141749679, K302E) and decreased (rs149456022, Q225H) LDL-C. Further, analysis of plasma lipoprotein particle subclasses by ion mobility in a subset of rs141749679 (K302E) carriers revealed higher levels of large LDL particles compared to noncarriers. In contrast to the effect of these variants in the Amish, the sortilin K302E mutation introduced into a C57BL6/J mouse via CRISPR/Cas9 had decreased non-high-density lipoprotein cholesterol, and the sortilin Q225H mutation did not alter cholesterol levels in mice. This is indicative of different effects of these mutations on cholesterol metabolism in the two species. To our knowledge, this is the first evidence that naturally occurring coding variants in SORT1 are associated with LDL-C, thus supporting SORT1 as the gene responsible for the association of the 1p13.3 locus with LDL-C.

Nuclear Magnetic Resonance–Based Metabolomics and Risk of CKD

Chronic kidney disease (CKD) leads to lipid and metabolic abnormalities, but a comprehensive investigation of lipids, lipoprotein particles, and circulating metabolites associated with the risk of CKD has been lacking. We examined the associations of nuclear magnetic resonance (NMR)-based metabolomics data with CKD risk in the UK Biobank study. Observational cohort study. A total of 91,532 participants in the UK Biobank Study without CKD and not receiving lipid-lowering therapy. Levels of metabolites including lipid concentration and composition within 14 lipoprotein subclasses, as well as other metabolic biomarkers were quantified via NMR spectroscopy. Incident CKD identified using ICD codes in any primary care data, hospital admission records, or death register records. Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals. We identified 2,269 CKD cases over a median follow-up period of 13.1 years via linkage with the electronic health records. After adjusting for covariates and correcting for multiple testing, 90 of 142 biomarkers were significantly associated with incident CKD. In general, higher concentrations of very-low-density lipoprotein (VLDL) particles were associated with a higher risk of CKD whereas higher concentrations of high-density lipoprotein (HDL) particles were associated with a lower risk of CKD. Higher concentrations of cholesterol, phospholipids, and total lipids within VLDL were associated with a higher risk of CKD, whereas within HDL they were associated with a lower risk of CKD. Further, higher triglyceride levels within all lipoprotein subclasses, including all HDL particles, were associated with greater risk of CKD. We also identified that several amino acids, fatty acids, and inflammatory biomarkers were associated with risk of CKD. Potential underreporting of CKD cases because of case identification via electronic health records. Our findings highlight multiple known and novel pathways linking circulating metabolites to the risk of CKD. The relationship between individual lipoprotein particle subclasses and lipid-related traits and risk of chronic kidney disease (CKD) in general population is unclear. Using data from 91,532 participants in the UK Biobank, we evaluated the associations of metabolites measured using nuclear magnetic resonance testing with the risk of CKD. We identified that 90 out of 142 lipid biomarkers were significantly associated with incident CKD. We found that very-low-density lipoproteins, high-density lipoproteins, the lipid concentration and composition within these lipoproteins, triglycerides within all the lipoprotein subclasses, fatty acids, amino acids, and inflammation biomarkers were associated with CKD risk. These findings advance our knowledge about mechanistic pathways that may contribute to the development of CKD.

Plant-based diet indices and lipoprotein particle subclass profiles: A cross-sectional analysis of middle- to older-aged adults

Background and aimsPlant-based diets (PBDs) are associated with favourable lipid profiles and cardiometabolic outcomes. However, limited data regarding PBD indices (PDIs) and lipoprotein subclasses exist. We examined overall PDI, healthful PDI (hPDI) and unhealthful PDI (uPDI) associations with lipid and lipoprotein profiles. MethodsThis cross-sectional analysis includes 1,986 middle- to older-aged adults from the Mitchelstown Cohort. The PDI, hPDI and uPDI scores were calculated from validated food frequency questionnaires. Higher PDI, hPDI and uPDI scores indicate a more PBD, healthful PBD and unhealthful PBD, respectively. Lipoprotein particle size and subclass concentrations were measured using nuclear magnetic resonance spectroscopy. Relationships between PDIs and lipid and lipoprotein profiles were examined via correlation and regression analyses adjusted for covariates. ResultsIn fully adjusted regression analyses, higher PDI scores were associated with lower high-density lipoprotein (HDL) cholesterol concentrations and more triglyceride-rich lipoprotein and small very low-density lipoprotein (VLDL) particles. Higher hPDI scores were negatively associated with non-HDL cholesterol concentrations, large VLDL and small HDL particles, the Lipoprotein Insulin Resistance Index (LP-IR) score and VLDL particle size. Higher uPDI scores were associated with lower HDL cholesterol and greater triglyceride concentrations and more medium and large VLDL, total LDL, small LDL and total non-HDL particles, less large LDL and large HDL particles, a greater LP-IR score, greater VLDL particle size and smaller LDL and HDL particle size. ConclusionsThis study provides novel evidence regarding associations between PBD quality and lipoprotein subclasses. A more unhealthful PBD was robustly associated with a more pro-atherogenic lipoprotein profile.

Sex-specific responses in glucose-insulin homeostasis and lipoprotein-lipid components after high-dose supplementation with marine n-3 PUFAs in abdominal obesity: a randomized double-blind crossover study.

Clinical studies on effects of marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and the plant-derived omega-6 (n-6) PUFA linoleic acid (LA) on lipoprotein-lipid components and glucose-insulin homeostasis have shown conflicting results, which may partly be explained by differential responses in females and males. However, we have lacked data on sexual dimorphism in the response of cardiometabolic risk markers following increased consumption of n-3 or n-6 PUFAs. To explore sex-specific responses after n-3 (EPA + DHA) or n-6 (LA) PUFA supplementation on circulating lipoprotein subfractions, standard lipids, apolipoproteins, fatty acids in red blood cell membranes, and markers of glycemic control/insulin sensitivity among people with abdominal obesity. This was a randomized double-blind crossover study with two 7-week intervention periods separated by a 9-week washout phase. Females (n = 16) were supplemented with 3 g/d of EPA + DHA (fish oil) or 15 g/d of LA (safflower oil), while males (n = 23) received a dose of 4 g/d of EPA + DHA or 20 g/d of LA. In fasting blood samples, we measured lipoprotein particle subclasses, standard lipids, apolipoproteins, fatty acid profiles, and markers of glycemic control/insulin sensitivity. The between-sex difference in relative change scores was significant after n-3 for total high-density lipoproteins (females/males: -11%*/-3.3%, p = 0.036; *: significant within-sex change), high-density lipoprotein particle size (+2.1%*/-0.1%, p = 0.045), and arachidonic acid (-8.3%*/-12%*, p = 0.012), and after n-6 for total (+37%*/+2.1%, p = 0.041) and small very-low-density lipoproteins (+97%*/+14%, p = 0.021), and lipoprotein (a) (-16%*/+0.1%, p = 0.028). Circulating markers of glucose-insulin homeostasis differed significantly after n-3 for glucose (females/males: -2.1%/+3.9%*, p = 0.029), insulin (-31%*/+16%, p < 0.001), insulin C-peptide (-12%*/+13%*, p = 0.001), homeostasis model assessment of insulin resistance index 2 (-12%*/+14%*, p = 0.001) and insulin sensitivity index 2 (+14%*/-12%*, p = 0.001), and quantitative insulin sensitivity check index (+4.9%*/-3.4%*, p < 0.001). We found sex-specific responses after high-dose n-3 (but not n-6) supplementation in circulating markers of glycemic control/insulin sensitivity, which improved in females but worsened in males. This may partly be related to the sex differences we observed in several components of the lipoprotein-lipid profile following the n-3 intervention. https://clinicaltrials.gov/, identifier [NCT02647333].

Abstract 12864: Nuclear Magnetic Resonance Lipoprotein Particle Subclasses Associate With Chronic Inflammatory Related Diseases Differently Than Cardiovascular Diseases: The Multi-Ethnic Study of Atherosclerosis

Introduction: Chronic inflammatory related disease (ChrIRD) is a novel outcome capturing non-cancer, non-cardiovascular clinical events driven by subclinical inflammation. Derangements in triglyceride-rich, low-density, and high-density lipoprotein particle (TRLp, LDLp, HDLp) subclass concentrations known to associate with inflammation and future cardiovascular disease have not been extensively evaluated in ChrIRD. Hypothesis: Lipoprotein particle subclasses may predict future ChrIRD in a similar direction and magnitude as with CVD. Methods: We measured 17 lipoprotein subclass particle concentrations by NMR spectroscopy in the Multi-Ethnic Study of Atherosclerosis (MESA). MESA is a US cohort including 6,759 White (38.6%), Chinese (11.9%), Black (27.6%), and Hispanic (22%) men and women initially aged 45-84 years and free of CVD. Participants were contacted at least annually to ascertain clinical events. Incident CVD (MI, Stroke, PAD, CV Death) and ChrIRD death/hospitalization risk per-quartile of lipoprotein marker levels were evaluated using disease-specific multivariable Cox regression models adjusted for traditional risk factors. Results: Disparate risk associations with ChrIRD and CVD were observed (Figure). Elevated small HDLp, total LDLp, and small TRLp, and were inversely associated with ChrIRD events. Additionally, larger TRLp size was associated higher ChrIRD risk. Metrics of HDL, LDL, and TRL associations with incident CVD as expected. In contrast, Very large TRLp was inverse with both clinical outcomes (HR [95% CI] CVD: 0.83 [0.75-0.96] ptrend=0.09, ChrIRD: 0.85 [0.69-0.99], ptrend =0.02). Conclusions: TRL, LDL, and HDL particles differentially associate with CVD and ChrIRD. Established predictors of CVD, including total TRL and LDL particles, small LDL, and large /medium TRL, may be inert or even protective in development of ChrIRD events due to distinct pathophysiologic contributions that warrant further investigation.

High-Density Lipoprotein Particle Subclasses in Statin-Treated Patients with Peripheral Artery Disease Predict Long-Term Survival.

Low-density lipoprotein-cholesterol reduction showed a strong reduction of cardiovascular (CV) event rates in CV disease. However, the residual risk of future CV events remains high, which especially extends to peripheral arterial disease (PAD). Nuclear magnetic resonance (NMR) spectroscopy offers a novel method for analysis of the lipoprotein spectrum. This study investigates lipoprotein subclasses using NMR spectroscopy and assesses implications for long-term survival in PAD. NMR spectroscopy was performed by Nightingale Inc., in 319 patients with stable PAD and well-controlled CV risk factors. Patients were followed-up for 10 years. During that period, 123 patients (38.5%) died, of those 68 (21.3%) were defined as CV deaths. Outcome data were analyzed by the Kaplan-Meier method and multivariable Cox-regression for lipoprotein particles. Small and medium high-density lipoprotein-particles (S-HDL-P and M-HDL-P) showed a significant inverse association with all-cause mortality in Cox-regression analyses after multivariable adjustment (S-HDL-P, hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.57-0.88; M-HDL-P, HR: 0.72, 95% CI: 0.58-0.90) for each increase of one standard deviation. In contrast, cholesterol-rich X-large HDL-particles (XL-HDL-P) showed a positive association with all-cause mortality (HR: 1.51, 95% CI: 1.20-1.89). Only the association between XL-HDL-P and CV death sustained multivariable adjustment (HR: 1.49, 95% CI: 1.10-2.02), whereas associations for S-HDL-P and M-HDL-P were attenuated (HR: 0.76, 95% CI: 0.57-1.01; HR: 0.80, 95% CI: 0.60-1.06). This study shows a novel association for a beneficial role of S-HDL-P and M-HDL-P but a negative association with higher cholesterol-rich XL-HDL-P for long-term outcome in well-treated patients with PAD. Thus, these results provide evidence that NMR-measured HDL particles identify patients at high CV residual risk beyond adequate lipid-lowering therapy.

The influence of menopause and cardiorespiratory fitness on lipoprotein particles in midlife women.

Lipoprotein particles may provide better information about cardiovascular risk than standard cholesterol measures for women. Whether lipoprotein subclasses change with menopausal stage is unclear. Given the high prevalence of low cardiorespiratory fitness in midlife women and benefit of cardiovascular disease risk, it is also important to understand the effect of fitness on lipoprotein profiles. This study evaluated the influence of menopausal status and fitness on lipoprotein particles in healthy midlife women. Lipoprotein particles were measured in high- (n = 25) and low- (n = 13) fit perimenopausal and late postmenopausal women, and in high-fit premenopausal (n = 10), perimenopausal (n = 12), and late postmenopausal women (n = 13). There were larger low-density lipoprotein particles (LDL-P; 21.7 ± 0.06 vs. 21.3 ± 0.1 nm, p = 0.002), more large LDL-P (623.1 ± 32.8 vs. 500.2 ± 52.6 nmol/L, p = 0.045), and fewer small LDL-P (145.5 ± 31.4 vs. 311.5 ± 44.7 nmol/L, p = 0.001) in the high-fit group vs. the low-fit group. High-density lipoprotein particles (HDL-P) were larger (10.1 ± 0.1 vs. 9.7 ± 0.1 nm, p = 0.002) in the high-fit group, with more large (14.8 ± 0.7 vs. 11.0 ± 0.9 μmol/L,p = 0.002), medium (12.9 ± 0.8 vs. 8.4 ± 0.9 μmol/L, p = 0.002) HDL-P, and fewer small HDL-P (10.2 ± 1.1 vs. 15.4 ± 1.6 μmol/L, p = 0.009) compared with the low-fit group. High-fit postmenopausal women had more large LDL-P (662.9 ± 47.5 nmol/L) compared with premenopausal women (479.1 ± 52.6 nmol/L, p = 0.035), and more HDL-P (40.2 ± 1.1 µmol/L) compared with premenopausal (34.9 ± 1.5 μmol/L, p = 0.023) and perimenopausal women (35.4 ± 1.3 μmol/L, p = 0.033). High fitness positively influences lipoprotein particles in healthy perimenopausal and late postmenopausal women. In healthy fit women, menopause may not have a large influence on lipoprotein particles. Novelty: In highly fit women, menopause may not have a negative influence on lipoprotein particle subclasses. High fitness is associated with a less atherogenic lipoprotein profile in perimenopausal and late postmenopausal women.

Association of inflammatory markers and lipoprotein particle subclasses with progression of coronary artery calcium: The multi-ethnic study of atherosclerosis

Background and aimsAtherosclerosis is a complex phenomenon manifesting several features typical of chronic inflammation and disorders of lipid metabolism. We assessed association of nuclear magnetic resonance (NMR) lipid variables and inflammatory markers with incident coronary artery calcium (CAC) and CAC progression among participants with baseline CAC ≥0. MethodsMESA is a longitudinal cohort study of 6,814 participants (aged 45–85). 3,115 had CAC = 0 and 2,896 had CAC>0 at baseline. Repeat CAC measurements were obtained (mean duration of follow up, 6.5 years). ResultsIL-6 (log pg/mL) and fibrinogen (50 mg/dL) were associated with a higher relative risk (RR) of incident CAC (HU) (RR = 1.09, p=0.010 & RR 1.05, p=0.004, respectively). Small LDL (100 nmol/L) (RR = 1.03, p<0.001) and log large VLDL (log nmol/L) (RR = 1.06, p=0.001) were associated with higher risks, whereas large HDL (μmol/L) was associated with an inverse risk of incident CAC (RR = 0.97, p< 0.001) in a model adjusted for follow up time, age, gender and race. Among participants with baseline CAC>0, progression of CAC was positively associated with hsCRP (log mg/L) (β = 1.99), IL-6 (log pg/mL) (β = 2.9), fibrinogen (50 mg/dL) (β = 1.0), large VLDL (log nmol/L) (β = 2.2), and small LDL (100 nmol/L) (β = 0.36) (all p values < 0.05) in a model adjusted for scanner type, age, gender and race. Relationships with inflammatory markers and NMR lipoprotein particles lost significance after adjustment for traditional risk factors and statin use. Traditional risk factors were strongly associated with both CAC incidence and progression with the exception of cholesterol parameters not associated with CAC progression in adjusted model. ConclusionsInflammatory markers and lipoprotein particles were associated with CAC incidence and progression in minimally adjusted models, but not after adjustment for traditional risk factors.

Lipoprotein subtypes after testosterone therapy in transmasculine adolescents

Differences in lipoprotein-particle subclasses between men and women start in puberty and narrow after menopause, suggesting a role for sex steroids. In this cross-sectional cohort study, we examined lipoprotein subtype profiles in transmasculine adolescents treated with testosterone. Transmasculine adolescents (n = 17) had lipoprotein profiles that were similar to those of cisgender males (n = 33) and more atherogenic than those of cisgender females (n = 32), with higher concentrations of small low-density lipoprotein (LDL) particles (435 ± 222 nmol/L vs. 244 ± 163 nmol/L, p = 0.008) and lower concentrations of large high-density lipoprotein (HDL) particles (1.5 ± 1.3 μmol/L vs 2.7 ± 1.2 μmol/L, p = 0.003) when compared to cisgender females. Thus, testosterone appears to be a major contributor to differences in lipoprotein profiles, a surrogate for cardiovascular disease risk, between cisgender women and both transgender and cisgender men.

Poly- and perfluoroalkyl substances (PFASs) and lipidomics and inflammatory proteomics in the human EuroMix study

BACKGROUND AND AIM: Exposure to PFASs has been associated with high cholesterol levels, lower vaccination response and higher childhood infections, in epidemiological studies. The mechanistic pathways involved are often unknown. Biomarkers of effect can provide insight in the biological implications of PFAS exposure. We explored the association between serum PFAS concentrations, lipoprotein particle subclasses and inflammatory biomarkers. METHODS: In 127 adult participants of the EuroMix human biomonitoring study (mean age: 40 years, 70% women) we determined the concentrations and lipid content of the major lipoproteins in two plasma samples by nuclear magnetic resonance and the serum concentrations of five perfluoroalkyl sulfonates (PFSAs) and six perfluoroalkyl carboxylates (PFCAs), and analysed their association by linear mixed-effect regression models. Further, we used an OLINK high-throughput proteomic assay to analyze plasma inflammatory proteins and explored the association with PFAS by linear regression analysis. RESULTS:Most PFCAs, and PFOS were positively associated with HDL and LDL cholesterol concentrations and negatively associated with VLDL cholesterol and triglyceride concentrations in all lipoproteins. One interquartile range (IQR) increase in PFNA, PFDoDA and PFOS was associated with 11%-12% higher HDL cholesterol, independent of HDL particle size. One IQR increase in PFTrDA, PFHpS and PFOS was associated with 9%-14% higher cholesterol concentrations in the small-size LDL. Long-chain PFCAs were negatively associated with the cholesterol and triglyceride concentrations in the large- and mid-sized VLDL subfractions. We found mostly negative associations between PFAS and inflammatory biomarkers. One IQR increase in PFOS, PFNA, PFDA, PFUnDA and PFDoDA was associated with 2-3% lower anti-inflammatory factors, HGF and IL-10RB. CONCLUSIONS:In this exploratory study, we aimed to identify serum lipoprotein and inflammatory biomarkers as markers of exposure to PFAS. We observed that PFAS exposure may influence the distribution and lipid composition of major lipoprotein subclasses, as well as modulation of inflammatory responses. KEYWORDS: Proteomics, PFAS, Cardiovascular diseases, Toxicology

Comparing dietary score associations with lipoprotein particle subclass profiles: A cross-sectional analysis of a middle-to older-aged population

Lipoprotein particle concentrations and size are associated with increased risk for atherosclerosis and premature cardiovascular disease. Studies also suggest that certain dietary behaviours may be cardioprotective. Limited comparative data regarding any dietary score/index-lipoprotein particle subclass associations exist. Thus, our objective was to assess relationships between the Dietary Approaches to Stop Hypertension (DASH), Health Eating Index-2015 (HEI-2015), Mediterranean Diet (MD) and Energy-adjusted Dietary Inflammatory Index (E-DII™) scores and plasma lipids and lipoprotein profiles to test the hypothesis that healthier diet (better quality and more anti-inflammatory) would be associated with a more favourable lipoprotein profile. This was a cross-sectional study of 1862 men and women aged 46-73 years, randomly selected from a large primary care centre in Ireland. DASH, HEI-2015, MD and E-DII scores were derived from food frequency questionnaires. Lipoprotein subclass particle concentrations and size were determined using nuclear magnetic resonance spectroscopy. Correlation and multivariate-adjusted linear regression analyses with correction for multiple testing were performed to examine dietary score relationships with lipoprotein particle subclasses. In fully adjusted models, higher diet quality or a more anti-inflammatory diet was associated with less large and medium very low-density lipoprotein (VLDL) (DASH and HEI-2015), intermediate-density lipoprotein (IDL) (DASH, MD and E-DII) and small high-density lipoprotein (HDL) (DASH, HEI-2015 and E-DII) particles. After accounting for multiple testing, relationships with large VLDL (DASH: β=-0.102, p=.037), IDL (DASH: β=-0.089, p=.037) and small HDL (DASH: β=-0.551, p=.014 and E-DII: β=0.483, p=.019) concentrations persisted. These findings provide evidence that better diet quality, determined by the DASH score, may be more closely associated with a more favourable lipoprotein particle subclass profile in middle-to older-aged adults than the HEI-2015, MD and E-DII scores. A less pro-atherogenic lipoprotein status may be a potential mechanism underlying the cardioprotective effects of higher dietary quality.

Changes in lipoprotein particle subclasses, standard lipids, and apolipoproteins after supplementation with n-3 or n-6 PUFAs in abdominal obesity: A randomized double-blind crossover study

Summary Background & aims Marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower circulating levels of triacylglycerols (TAGs), and the plant-derived omega-6 (n-6) PUFA linoleic acid (LA) may reduce cholesterol levels. Clinical studies on effects of these dietary or supplemental PUFAs on other blood fat fractions are few and have shown conflicting results. This study aimed to determine effects of high-dose supplemental n-3 (EPA + DHA) and n-6 (LA) PUFAs from high-quality oils on circulating lipoprotein subfractions and standard lipids (primary outcomes), as well as apolipoproteins, fatty acids, and glycemic control (secondary outcomes), in females and males with abdominal obesity. Methods This was a randomized double-blind crossover study with two 7-wk intervention periods separated by a 9-wk washout phase. Females (n = 16) were supplemented with 3 g/d of EPA + DHA (TAG fish oil) or 15 g/d of LA (safflower oil), while males (n = 23) received a dose of 4 g/d of EPA + DHA or 20 g/d of LA. In fasting blood samples, we investigated lipoprotein particle subclasses by nuclear magnetic resonance spectroscopy, as well as standard lipids, apolipoproteins, fatty acid profiles, and glucose and insulin. Data were analyzed by linear mixed-effects modeling with ‘subjects’ as the random factor. Results The difference between interventions in relative change scores was among the lipoprotein subfractions significant for total very-low-density lipoproteins (VLDLs) (n-3 vs. n-6: −38%∗ vs. +16%, p Conclusions High-dose supplementation of high-quality oils with n-3 (EPA + DHA) or n-6 (LA) PUFAs was followed by reductions in primarily TAG- or cholesterol-related markers, respectively. The responses after both interventions point to changes in the lipoprotein–lipid–apolipoprotein profile that have been associated with reduced cardiometabolic risk, also among people with TAG or LDL-C levels within the normal range. Registration Registered under ClinicalTrials.gov Identifier: NCT02647333. Clinical trial registration Registered at https://clinicaltrials.gov/ct2/show/NCT02647333 .

The PNPLA3-I148M Variant Confers an Antiatherogenic Lipid Profile in Insulin-resistant Patients.

The I148M (rs738409-G) variant in PNPLA3 increases liver fat content but may be protective against cardiovascular disease. Insulin resistance (IR) amplifies the effect of PNPLA3-I148M on liver fat. To study whether PNPLA3-I148M confers an antihyperlipidemic effect in insulin-resistant patients. Cross-sectional study comparing the impact of PNPLA3-I148M on plasma lipids and lipoproteins in 2 cohorts, both divided into groups based on rs738409-G allele carrier status and median HOMA-IR. Tertiary referral center. A total of 298 obese patients who underwent a liver biopsy during bariatric surgery (bariatric cohort: age 49 ± 9 years, body mass index [BMI] 43.2 ± 6.8 kg/m2), and 345 less obese volunteers in whom liver fat was measured by proton magnetic resonance spectroscopy (nonbariatric cohort: age 45 ± 14 years, BMI 29.7 ± 5.7 kg/m2). Nuclear magnetic resonance profiling of plasma lipids, lipoprotein particle subclasses and their composition. In both cohorts, individuals carrying the PNPLA3-I148M variant had significantly higher liver fat content than noncarriers. In insulin-resistant and homozygous carriers, PNPLA3-I148M exerted a distinct antihyperlipidemic effect with decreased very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) particles and their constituents, and increased high-density lipoprotein particles and their constituents, compared with noncarriers. VLDL particles were smaller and LDL particles larger in PNPLA3-I148M carriers. These changes were geometrically opposite to those due to IR. PNPLA3-I148M did not have a measurable effect in patients with lower IR, and its effect was smaller albeit still significant in the less obese than in the obese cohort. PNPLA3-I148M confers an antiatherogenic plasma lipid profile particularly in insulin-resistant individuals.

Protective lifestyle behaviours and lipoprotein particle subclass profiles in a middle-to older-aged population

Background and aimsLipoprotein particle size is associated with increased atherosclerosis and cardiovascular disease risk. Certain lifestyle behaviours may be cardioprotective. We examined lipoprotein particle size and concentration relationships with a protective lifestyle behaviour (PLB) score. MethodsThis was a cross-sectional analysis of 2045 middle-to older-aged adults. Lipoprotein particle subclass size and concentrations were determined using nuclear magnetic resonance spectroscopy. Five protective behaviours included never smoking, moderate alcohol intake, moderate to vigorous physical activity, a high-quality diet (upper 40% Dietary Approaches to Stop Hypertension score) and a normal body mass index (BMI) (18.5–24.9 kg/m2). Linear and logistic regression analyses tested individual protective behaviour and PLB score associations with lipoprotein subclasses. ResultsIndividual behaviour associations varied according to lipoprotein subclass, with normal BMI showing the greatest number of significant relationships. Logistic regression analyses revealed that subjects with the fewest number of protective behaviours had 1.4–2.8 increased odds of having less favourable lipoprotein profiles defined as above or below median level lipoprotein particle subclass size or concentration. Following additional adjustment for BMI, significant trend relationships were observed between the PLB score and large and medium very low-density lipoprotein (p = 0.001 and p < 0.001), total and smaller low-density lipoprotein (LDL) concentrations (p = 0.008 and p < 0.001), LDL size (p = 0.003) and a lipoprotein insulin resistance score (p = 0.003). ConclusionsResults show a cumulative protective effect of healthy lifestyle behaviours against an unfavourable potentially pro-atherogenic lipoprotein profile in middle-to older-aged adults, highlighting the importance of lifestyle promotion in healthy ageing.

Squeezing lipids: NMR characterization of lipoprotein particles under pressure

Determining the particle size and number of lipoprotein components found in blood plasma (HDL, LDL and VLDL) has become an important clinical tool in diagnosing risk of cardiovascular disease. Proton (1H) NMR spectroscopy methods to quantify lipoprotein particle subclasses have been advancing since NMR lineshape analysis of plasma samples was first proposed in the 1990’s. NMR methods, including a more recent DOSY-based diffusion spectroscopy test, provide the foundation for the advanced lipoprotein tests, including Lipoprotein® and Liposcale® analyses available for clinical use to determine particle size and number. At the time of this submission, no NMR studies exist which explore physical parameters of individual lipoprotein fractions when they are deformed by pressure. This study reports 1H NMR frequency shifts and T2* measurements for the broad methyl peak attributed to terminal methyls (cholesteryl positions 26, 27 and terminal acyl methyl groups) in three primary lipoprotein fractions as a function of hydraulic pressure. This terminal CH3 resonance shifted linearly upfield as a function of pressure for HDL and VLDL (observed slopes of −0.014 Hz/bar). The LDL terminal CH3 resonance shows segmented behavior, with a shallow slope between 0–900 bar (−0.008 hz/bar) and a slope similar to HDL and VDL across the range from 1000 to 2400 bar (slope −0.016 Hz/bar). 1H T2* values measured for VLDL and HDL dropped linearly with increasing pressure. 1H T2* values for LDL demonstrated segmented behavior as a function of pressure. The unique behavior observed for LDL terminal CH3 frequency and 1H T2* trends suggests an approximate pressure at which phase transition occurs.

Relations of GlycA and lipoprotein particle subspecies with cardiovascular events and mortality: A post hoc analysis of the AIM-HIGH trial

The Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides and Impact on Global Health Outcomes trial showed no incremental benefit of extended-release niacin (ERN) therapy added to simvastatin in subjects with cardiovascular disease (CVD). To examine the effects of ERN treatment on lipoprotein particles and GlycA, a new marker of systemic inflammation, and their relations with incident CVD events including mortality. GlycA and very low-density lipoprotein, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) particle subclasses were quantified by nuclear magnetic resonance spectroscopy using available stored baseline (n=2754) and 1-year in-trial (n=2581) samples. Associations with CVD events and all-cause mortality were assessed using multivariable Cox proportional hazards regression adjusted for age, sex, diabetes, treatment assignment, and lipoproteins. Compared to placebo, ERN treatment lowered very low-density lipoprotein and LDL and increased HDL particle concentrations, increased LDL and HDL particle sizes (all P<.0001), but did not affect GlycA. Baseline and in-trial GlycA levels were associated with increased risk of CVD events: hazard ratio (HR) per SD increment, 1.17 (95% confidence interval [CI], 1.06-1.28) and 1.13 (1.02-1.26), respectively. However, none of the lipoprotein particle classes or subclasses was associated with incident CVD. By contrast, all-cause mortality was significantly associated with both GlycA (baseline HR: 1.46 [1.22-1.75]; in-trial HR: 1.41 [1.24-1.60]) and low levels of small HDL particles (baseline HR: 0.69 [0.56-0.86]; in-trial HR: 0.69 [0.56-0.86]). This Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides and Impact on Global Health Outcomes trial post hoc substudy indicates that inflammation, as indexed by GlycA, is unaffected by ERN treatment but is significantly associated with the residual risk of CVD and death in patients treated to low levels of LDL cholesterol.

Lipoprotein apheresis affects lipoprotein particle subclasses more efficiently compared to the PCSK9 inhibitor evolocumab, a pilot study

Lipoprotein apheresis and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are last therapeutic resorts in patients with familial hypercholesterolemia (FH). We explored changes in lipoprotein subclasses and high-density lipoprotein (HDL) function when changing treatment from lipoprotein apheresis to PCSK9 inhibition.We measured the levels of low-density lipoprotein (LDL) and HDL particle subclasses, serum amyloid A1 (SAA1), paraoxonase-1 (PON1) activity and cholesterol efflux capacity (CEC) in three heterozygous FH patients. Concentrations of all LDL particle subclasses were reduced during apheresis (large 68.0 ± 17.5 to 16.3 ± 2.1 mg/dL, (p = 0.03), intermediate 38.3 ± 0.6 to 5.0 ± 3.5 mg/dL (p = 0.004) and small 5.0 ± 2.6 to 0.2 ± 0.1 mg/dL (p = 0.08)). There were non-significant reductions in the LDL subclasses during evolocumab treatment. There were non-significant reductions in subclasses of HDL particles during apheresis, and no changes during evolocumab treatment. CEC was unchanged throughout the study, while the SAA1/PON1 ratio was unchanged during apheresis but decreased during evolocumab treatment.In conclusion, there were significant reductions in large and intermediate size LDL particles during apheresis, and a non-significant reduction in small LDL particles. There were only non-significant reductions in the LDL subclasses during evolocumab treatment.

Plasma Lipoprotein Particle Subclasses in Preterm Infants.

A pilot study to determine lipoprotein classes and subclasses in premature infants and examine associations with nutritional intake, gestational age (GA), and morbidity. Plasma lipoprotein particle concentrations were analyzed in a cohort of 15 premature infants in the first 5 days of life and again at 2 weeks. Breast milk samples were analyzed for fatty acid content. Associations between lipoprotein particle subclasses and GA, breast milk intake, milk fatty acid intake, and chronic lung disease (CLD) were determined. At 2 weeks of age, more premature infants had higher concentrations of total very low-density lipoprotein and lower concentrations of total high-density lipoprotein (HDL) and large HDL particles (similar to profiles seen in adults and children with infectious disease, cardiometabolic disease, and diabetes). Lower total HDL, large HDL, and medium HDL and a higher small HDL:total HDL ratio at 2 weeks were each associated with CLD with GA a likely confounder. Intake of human milk C18 and C20 fatty acids was inversely correlated with plasma total LDL concentration at 2 weeks of age. Dyslipidemia was common in extremely premature infants and was associated with CLD and with lower intake of specific long chain fatty acids.

Lipids, lipoprotein distribution and depressive symptoms: the Multi-Ethnic Study of Atherosclerosis.

Previous studies suggest lower concentrations of total and high-density lipoprotein (HDL) cholesterol to be predictive of depression. We therefore investigated the relationship of lipids and lipoprotein distribution with elevated depressive symptoms (EDS) in healthy men and women from the Multi-Ethnic Study of Atherosclerosis (MESA). Participants were followed up over a 9.5-year period. EDS were defined as a Center for Epidemiological Studies Depression (CES-D) score ⩾16 and/or use of antidepressant drugs. Lipoprotein distribution was determined from plasma using nuclear magnetic resonance spectroscopy. Among 4938 MESA participants (mean age=62 years) without EDS at baseline, 1178 (23.9%) developed EDS during follow-up. In multivariable Cox regression analyses, lower total, low-density lipoprotein (LDL) and non-HDL cholesterol concentrations at baseline were associated with incident EDS over 9.5 years (hazards ratio (HR)=1.11–1.12 per s.d. decrease, all P<0.01), after adjusting for demographic factors, traditional risk factors including LDL cholesterol, HDL cholesterol and triglycerides. Lipoprotein particle subclasses and sizes were not associated with incident EDS. Among participants without EDS at both baseline and visit 3, a smaller increase in total or non-HDL cholesterol between these visits was associated with lower risk of incident EDS after visit 3 (HR=0.88–0.90 per s.d. decrease, P<0.05). Lower baseline concentrations of total, LDL and non-HDL cholesterol were significantly associated with a higher risk of incident EDS. However, a short-term increase in cholesterol concentrations did not help to reduce the risk of EDS. Further studies are needed to replicate our findings in cohorts with younger participants.