scholarly journals Aggregation Susceptibility of Low-Density Lipoproteins—A Novel Modifiable Biomarker of Cardiovascular Risk

2021 ◽  
Vol 10 (8) ◽  
pp. 1769
Author(s):  
Katariina Öörni ◽  
Petri T. Kovanen
Keyword(s):  
Ex Vivo ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Atherosclerotic Cardiovascular Disease ◽  
Low Density ◽  
Cholesterol Crystals ◽  
Ldl Particles ◽  
Arterial Intima ◽  
Matrix Bound ◽  
Atherosclerotic Cardiovascular Diseases

Circulating low-density lipoprotein (LDL) particles enter the arterial intima where they bind to the extracellular matrix and become modified by lipases, proteases, and oxidizing enzymes and agents. The modified LDL particles aggregate and fuse into larger matrix-bound lipid droplets and, upon generation of unesterified cholesterol, cholesterol crystals are also formed. Uptake of the aggregated/fused particles and cholesterol crystals by macrophages and smooth muscle cells induces their inflammatory activation and conversion into foam cells. In this review, we summarize the causes and consequences of LDL aggregation and describe the development and applications of an assay capable of determining the susceptibility of isolated LDL particles to aggregate when exposed to human recombinant sphingomyelinase enzyme ex vivo. Significant person-to-person differences in the aggregation susceptibility of LDL particles were observed, and such individual differences largely depended on particle lipid composition. The presence of aggregation-prone LDL in the circulation predicted future cardiovascular events in patients with atherosclerotic cardiovascular disease. We also discuss means capable of reducing LDL particles’ aggregation susceptibility that could potentially inhibit LDL aggregation in the arterial wall. Whether reductions in LDL aggregation susceptibility are associated with attenuated atherogenesis and a reduced risk of atherosclerotic cardiovascular diseases remains to be studied.

Intralysosomal Accumulation of Colloidal Gold-Low Density Lipoprotein Conjugates in Chloroquine-Treated Fibroblasts

1985 ◽  
Vol 43 ◽  
pp. 546-547 ◽  
Author(s):  
Dean A. Handley ◽  
Cynthia M. Arbeeny ◽  
Larry D. Witte
Keyword(s):  
Colloidal Gold ◽  
Cultured Cells ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Coated Vesicle ◽  
Low Density ◽  
Cholesterol Esters ◽  
Cultured Fibroblasts ◽  
Surface Receptors ◽  
Ldl Particles

Low density lipoproteins (LDL) are the major cholesterol carrying particles in the blood. Using cultured cells, it has been shown that LDL particles interact with specific surface receptors and are internalized via a coated pit-coated vesicle pathway for lysosomal catabolism. This (Pathway has been visualized using LDL labeled to ferritin or colloidal gold. It is now recognized that certain lysomotropic agents, such as chloroquine, inhibit lysosomal enzymes that degrade protein and cholesterol esters. By interrupting cholesterol ester hydrolysis, chloroquine treatment results in lysosomal accumulation of cholesterol esters from internalized LDL. Using LDL conjugated to colloidal gold, we have examined the ultrastructural effects of chloroquine on lipoprotein uptake by normal cultured fibroblasts.

scholarly journals Impact of Adoption of Directly Measured Low-Density Lipoprotein-Cholesterol (LDL-C) on Targets of Lipid Control and Its Comparison With Friedewald Formula-Calculated LDL Cholesterol in People With Type-2 Diabetes Mellitus

2020 ◽  
pp. 263246362097804
Author(s):  
Rejitha Jagesh ◽  
Mathew John ◽  
Manju Manoharan Nair Jalaja ◽  
Tittu Oommen ◽  
Deepa Gopinath
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Atherosclerotic Cardiovascular Disease ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol ◽  
Friedewald Formula

Objectives: The accurate and precise measurement of low-density lipoprotein-cholesterol (LDL-C) is important in the assessment of atherosclerotic cardiovascular disease risk (ASCVD) in people with diabetes mellitus. This study aimed at comparing directly measured LDL-C with Friedewald formula (FF)-calculated LDL-C (c-LDL-C) in people with type-2 diabetes. Methods: Fasting lipid profiles of 1905 people with type-2 diabetes, whose LDL-C was estimated by direct LDL assay, were chosen for the study. In the same group, LDL-C was calculated with FF. Correlation and agreement between these methods were analyzed at various strata of triglycerides (TGs). The possibility of misclassifying people at various levels of LDL-C targets proposed in literature was calculated. Results: The mean LDL-C levels were lower in the c-LDL-C group across various TG strata. A significant correlation was found between c-LDL-C and direct LDL-C for all the study samples ( r = 0.948, P < .001) and across all TG strata. Analysis of agreement showed a positive bias for direct LDL-C which increased at higher strata of TGs. c-LDL-C underestimated ASCVD by misclassifying people at various LDL-C target levels. Conclusion: There is a difference between direct LDL-C and c-LDL-C values in people with diabetes and this may result in misclassifying ASCVD especially at lower levels of LDL-C and higher levels of TGs.

Low-density lipoprotein cholesterol goal attainment and treatment patterns in a cohort of >143,000 patients with atherosclerotic cardiovascular disease in Ontario, Canada

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Fairbairn ◽  
P Oh ◽  
R Goeree ◽  
R.M Rogoza ◽  
M Packalen ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Goal Attainment ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Data Repository ◽  
Funding Source ◽  
Atherosclerotic Cardiovascular Disease ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol

Abstract Background/Introduction Limited real-world data are available on attainment of low-density lipoprotein cholesterol (LDL-C) treatment goals in patients with atherosclerotic cardiovascular disease (ASCVD) in Canada. Purpose A retrospective observational study was conducted to describe types of ASCVD events/procedures, time between events and use of lipid lowering treatment (LLT) in patients who did not achieve LDL-C goal. Methods Patients in Ontario ≥65 years with a primary ASCVD event/procedure between 1 Apr 2005 and 31 Mar 2016, treated with an LLT and with index and follow up LDL-C values were identified from claims data at the Institute for Clinical Evaluative Sciences data repository. Patients were assessed over a 1-year follow up period for LDL-C goal attainment (&lt;2.0 mmol/L or 50% reduction from index LDL-C) and analysed by LLT and by index event type. Results Overall, 28% of 143,302 patients ≥65 years on LLT failed to attain LDL-C goal at follow up (Figure). The proportion of patients failing to achieve LDL-C goal decreased from 35% to 22% over the 11-year study period. Mean time between index and follow up LDL-C (based on lowest score &gt;2 weeks and up to 1 year after index LDL-C) was 203±97 days. When analysed by low-, moderate- or high-intensity statin, 57%, 30%, and 22% of patients failed to achieve LDL-C goal at follow up, respectively. Conclusions In this study, more than 1 in 4 patients with ASCVD in Ontario failed to achieve guideline recommended LDL-C goal despite treatment. In particular, ∼1 in 3 patients with cerebral and peripheral arterial disease were not at goal. An opportunity exists to better manage these high risk ASCVD patients with further statin intensification and additional LLTs This study made use of de-identified data from the ICES Data Repository, which is managed by the Institute for Clinical Evaluative Sciences with support from its funders and partners: Canada's Strategy for Patient-Oriented Research (SPOR), the Ontario SPOR Support Unit, the Canadian Institutes of Health Research and the Government of Ontario. The opinions, results and conclusions reported are those of the authors. No endorsement by ICES or any of its funders or partners is intended or should be inferred. Parts of this material are based on data and/or information compiled and provided by CIHI. However, the analyses, conclusions, opinions and statements expressed in the material are those of the author(s), and not necessarily those of CIHI Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Amgen Canada Inc.

scholarly journals Long-term fasting improves lipoprotein-associated atherogenic risk in humans

2021 ◽  
Author(s):  
Franziska Grundler ◽  
Dietmar Plonné ◽  
Robin Mesnage ◽  
Diethard Müller ◽  
Cesare R. Sirtori ◽  
...  
Keyword(s):  
Low Density Lipoprotein ◽  
Plasma Lipid ◽  
Density Lipoprotein ◽  
Apolipoprotein A1 ◽  
Health Concern ◽  
Low Density ◽  
Lipoprotein Subclasses ◽  
Ldl Particles ◽  
Increased Risk

Abstract Purpose Dyslipidemia is a major health concern associated with an increased risk of cardiovascular mortality. Long-term fasting (LF) has been shown to improve plasma lipid profile. We performed an in-depth investigation of lipoprotein composition. Methods This observational study included 40 volunteers (50% men, aged 32–65 years), who underwent a medically supervised fast of 14 days (250 kcal/day). Changes in lipid and lipoprotein levels, as well as in lipoprotein subclasses and particles, were measured by ultracentrifugation and nuclear magnetic resonance (NMR) at baseline, and after 7 and 14 fasting days. Results The largest changes were found after 14 fasting days. There were significant reductions in triglycerides (TG, − 0.35 ± 0.1 mmol/L), very low-density lipoprotein (VLDL)-TG (− 0.46 ± 0.08 mmol/L), VLDL-cholesterol (VLDL-C, − 0.16 ± 0.03 mmol/L) and low-density lipoprotein (LDL)-C (− 0.72 ± 0.14 mmol/L). Analysis of LDL subclasses showed a significant decrease in LDL1-C (− 0.16 ± 0.05 mmol/L), LDL2-C (− 0.30 ± 0.06 mmol/L) and LDL3-C (− 0.27 ± 0.05 mmol/L). NMR spectroscopy showed a significant reduction in large VLDL particles (− 5.18 ± 1.26 nmol/L), as well as large (− 244.13 ± 39.45 nmol/L) and small LDL particles (− 38.45 ± 44.04 nmol/L). A significant decrease in high-density lipoprotein (HDL)-C (− 0.16 ± 0.04 mmol/L) was observed. By contrast, the concentration in large HDL particles was significantly raised. Apolipoprotein A1 decreased significantly whereas apolipoprotein B, lipoprotein(a), fibrinogen and high-sensitivity C-reactive protein were unchanged. Conclusion Our results suggest that LF improves lipoprotein levels and lipoprotein subclasses and ameliorates the lipoprotein-associated atherogenic risk profile, suggesting a reduction in the cardiovascular risk linked to dyslipidemia. Trial Registration Study registration number: DRKS-ID: DRKS00010111 Date of registration: 03/06/2016 “retrospectively registered”.

Eligibility for PCSK9 inhibitors based on the 2019 ESC/EAS and 2018 ACC/AHA guidelines

2020 ◽  
pp. 204748732094010
Author(s):  
Konstantinos C Koskinas ◽  
Baris Gencer ◽  
David Nanchen ◽  
Mattia Branca ◽  
David Carballo ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
High Risk ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Atherosclerotic Cardiovascular Disease ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol ◽  
Coronary Syndrome ◽  
Coronary Syndromes

Aims The 2018 American College of Cardiology (ACC)/American Heart Association (AHA) and 2019 European Society of Cardiology (ESC)/European Atherosclerosis Society (EAS) lipid guidelines recently updated their recommendations regarding proprotein convertase subtilisin/kexin-9 inhibitors (PCSK9i). We assessed the potential eligibility for PCSK9i according to the new guidelines in patients with acute coronary syndromes. Methods and results We analysed a contemporary, prospective Swiss cohort of patients hospitalised for acute coronary syndromes. We modelled a statin intensification effect and an incremental ezetimibe effect on low-density lipoprotein-cholesterol levels among patients who were not on high-intensity statins or ezetimibe. One year after the index acute coronary syndrome event, treatment eligibility for PCSK9i was defined as low-density lipoprotein-cholesterol of 1.4 mmol/l or greater according to ESC/EAS guidelines. For ACC/AHA guidelines, treatment eligibility was defined as low-density lipoprotein-cholesterol of 1.8 mmol/l or greater in the presence of very high-risk atherosclerotic cardiovascular disease, defined by multiple major atherosclerotic cardiovascular disease events and/or high-risk conditions. Of 2521 patients, 93.2% were treated with statins (53% high-intensity statins) and 7.3% with ezetimibe at 1 year, and 54.9% had very high-risk atherosclerotic cardiovascular disease. Low-density lipoprotein-cholesterol levels less than 1.8 mmol/l and less than 1.4 mmol/l at 1 year were observed in 37.5% and 15.7% of patients, respectively. After modelling the statin intensification and ezetimibe effects, these numbers increased to 76.1% and 49%, respectively. The proportion of patients eligible for PCSK9i was 51% according to ESC/EAS criteria versus 14% according to ACC/AHA criteria. Conclusions In this analysis, the 2019 ESC/EAS guidelines rendered half of all post-acute coronary syndrome patients potentially eligible for PCSK9i treatment, as compared to a three-fold lower eligibility rate based on the 2018 ACC/AHA guidelines.

scholarly journals Focus on… Praluent®

2020 ◽  
pp. 175-178
Author(s):  
L Steyn
Keyword(s):  
Cardiovascular Disease ◽  
High Density Lipoprotein ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Pivotal Role ◽  
Atherosclerotic Cardiovascular Disease ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol ◽  
Lipoprotein Receptors

Cholesterol plays a pivotal role in the functioning of healthy cells. Being mostly lipophilic, cholesterol is transported in the blood inside lipophilic particles, e.g. high-density lipoprotein (HDL), low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL). Hypercholesterolaemia refers to elevated low-density lipoprotein cholesterol (LDL-C) levels, and increases the risk for premature atherosclerotic cardiovascular disease (ASCVD). Low-density lipoprotein receptors (LDL-R) on the surface of hepatocytes, are the primary receptors involved in clearing circulating LDL-C.

scholarly journals Markedly Increased Small Dense Low-Density Lipoprotein During Acute Phase in Childhood and Adolescent Nephrotic Syndrome

2020 ◽  
Author(s):  
Keisuke Sugimoto ◽  
Kohei Miyazaki ◽  
Takuji Enya ◽  
Tomoki Miyazawa ◽  
Yuichi Morimoto ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Acute Phase ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Lipid Profiles ◽  
Atherogenic Index ◽  
Childhood And Adolescence ◽  
Low Density ◽  
Ldl Particles ◽  
Initial Onset

Abstract Background: Hyperlipidemia is an important characteristic feature of idiopathic nephrotic syndrome (NS) in children. This study was conducted to examine the lipid profiles, including small dense low-density lipoprotein (sdLDL-C), in childhood-onset NS.Methods: This retrospective study enrolled patients diagnosed with initial-onset NS in childhood and adolescence. Study parameters included lipid profiles. The “alternative LDL window” comprises the number and sizes of LDL particles estimated according to non-HDL-C and TG levels.Results: A total of 39 patients were enrolled who exhibited markedly increased lipid abnormalities, including TC, TG, LDL-C, and non-HDL-C levels (TC, 409.7 TC, TG, and sizes of LDL particles estimated as non-HDL-C, 332.3). Of the 39 patients, 32 (82%) were categorized in the area of hyper-TG/-non-HDL levels, which is considered as sdLDL. A positive correlation was found between non-HDL-C and TC (r = 0.96, P < 0.001), TG (r = 0.38, P = 0.018), LDL-C (r = 0.84, P < 0.001), TC/HDL (r = 0.53, P < 0.001), and atherogenic index of plasma (r = 0.42, P = 0.008).Conclusions: Our study demonstrated markedly increased lipid profiles during the acute phase of NS. Evaluation of lipid profiles using the “alternative LDL window” may help understand the state of hyperlipidemia in NS.

Abstract 566: MicroRNA-146a Deficiency Prevents PCSK9 Gain-of-Function Mutation-induced Hypercholesterolemia in Mice

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Shayan Mohammadmoradi ◽  
Aida Javidan ◽  
Weihua Jiang ◽  
Jessica Moorleghen ◽  
Venkateswaran Subramanian
Keyword(s):  
Plasma Cholesterol ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Western Diet ◽  
Size Exclusion ◽  
Gel Chromatography ◽  
Low Density ◽  
Distribution Analysis ◽  
Gain Of Function ◽  
Ldl Particles

Background and Objective: Mimetic mediated activation of microRNA 146a (miR-146a) reduces atherosclerosis via suppression of nuclear factor-κB-driven inflammation in mice. The purpose of this study was to determine whether miR-146a influences plasma cholesterol in hypercholesterolemic mice. Methods and Results: To induce hypercholesterolemia, female C57BL/6 miR-146a WT (n=8) and miR-146a KO (n=8) mice were injected intraperitoneally with an adeno-associated viral vector (AAV) expressing the proprotein convertase subtilisin/kexin type 9 (PSCK9 D377Y) gain-of-function mutant at a dose of 3 x 10 10 genomic copies/mouse. After infection, mice were fed a Western diet (21% wt/wt milk fat; 0.15% wt/wt cholesterol) for sixteen weeks, and plasma PCSK9 and total cholesterol concentrations were monitored monthly using an enzymatic assay. Plasma PCSK9 concentrations were profoundly increased 4 weeks post injection (Baseline: WT - 179 ± 12 vs KO - 207 ± 12; Week 4: WT - 1700 ± 148 vs KO - 2689 ± 305 ng/ml) and remained significantly high during 16 weeks (WT - 882 ± 142 vs KO - 718 ± 109 ng/ml; p<0.05 vs baseline) of Western diet feeding. Consistent with increased plasma PCSK9 concentrations, plasma cholesterol concentrations were increased in both groups of mice. Interestingly, miR-146a KO group mice showed less significant increase in plasma cholesterol compared to WT group (Baseline: WT - 88 ± 3 vs KO - 83 ± 3; Week 4: WT - 328 ± 25 vs KO - 195 ± 18 mg/dl) irrespective of the comparable plasma PCSK9 concentrations. Also, lipoprotein distribution analysis with size exclusion gel chromatography revealed that miR-146a KO mice showed a strong reduction in high density lipoprotein (HDL) particles while very low density lipoprotein (VLDL) and low density lipoprotein (LDL) particles were not affected. Conclusion: Our findings suggests that miR146a plays a critical role in the regulation of HDL particles in PCSK9 gain-of-function mutant-induced hypercholesterolemia in mice. Future studies will identify gene targets influenced by miR-146a in regulating HDL-cholesterol in hypercholesterolemic mice.

Abstract P181: Atherogenic Lipoproteins and Incident Atherosclerotic Cardiovascular Disease in the Framingham Offspring Study

Circulation ◽  
2020 ◽  
Vol 141 (Suppl_1) ◽  
Author(s):  
Hiroaki Ikezaki ◽  
Elise Lim ◽  
Ching-Ti Liu ◽  
L Adrienne Cupples ◽  
Bela F Asztalos ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cardiovascular Disease ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Atherosclerotic Cardiovascular Disease ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol ◽  
Significant Information ◽  
Ascvd Risk

Introduction: Elevated plasma low-density lipoprotein cholesterol (LDL-C), small-dense LDL-C (sdLDL-C), LDL-triglyceride (LDL-TG), triglycerides (TG), remnant-lipoprotein cholesterol (RLP-C), triglyceride-rich lipoprotein-C (TRL-C), very low-density lipoprotein cholesterol (VLDL-C), and lipoprotein(a) [Lp(a)] levels have been associated with increased atherosclerotic cardiovascular disease (ASCVD) risk. However, these parameters have not been included in risk factors for ASCVD in the pooled cohort equation (PCE). Hypothesis: We assessed the hypothesis that these atherogenic lipoprotein parameters add significant information for ASCVD risk prediction in the Framingham Offspring Study. Methods: We evaluated 3,147 subjects without ASCVD at baseline (mean age 58 years) from participants of Framingham Offspring Study cycle 6, 677 (21.5%) of whom developed inclusive ASCVD over 16 years. Biomarkers of risk were assessed in frozen plasma samples. Total cholesterol, TG, HDL-C, direct LDL-C, sdLDL-C, LDL-TG, Lp(a), RLP-C, and TRL-C were measured by standardized automated analysis. Calculated LDL-C, large buoyant low-density lipoprotein cholesterol (lbLDL-C), VLDL-C, and non-HDL-C values were calculated. Data were analyzed using Cox proportional regression analysis and net reclassification improvement (NRI) analysis to identify parameters significantly associated with the incidence of ASCVD after controlling for standard ASCVD risk factor and applying the PCE model. Results: All specialized lipoprotein parameters were significant ASCVD risk factors on univariate analysis, but only direct LDL-C, sdLDL-C, and Lp(a) were significant on multivariate analysis with standard risk factors in the model. Together these parameters significantly improved the model c statistic (0.716 vs 0.732, P < 0.05) and net risk reclassification (mean NRI 0.104, P < 0.01) for ASCVD risk. Using the ASCVD risk pooled cohort equation, sdLDL-C, TG, LDL-TG, LDL-C, RLP-C, and TRL-C individually added significant information, but no other parameter added significant information with sdLDL-C (hazard ratio 1.30 for 75th vs 25th percentile, P < 0.0001) in the model. Conclusions: In multivariate analysis, sdLDL-C, direct LDL-C, and Lp(a) contributed significantly to ASCVD risk, but only sdLDL-C added significant risk information to the PCE model, indicating that sdLDL-C may be the most atherogenic lipoprotein particle.

Sign in / Sign up

Export Citation Format

Share Document