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Clinical Chemistry Jan 2021Current guidelines target low-density lipoprotein cholesterol (LDL-C) concentrations to reduce atherosclerotic cardiovascular disease (ASCVD) risk, and yet clinical... (Review)
Review
BACKGROUND
Current guidelines target low-density lipoprotein cholesterol (LDL-C) concentrations to reduce atherosclerotic cardiovascular disease (ASCVD) risk, and yet clinical trials demonstrate persistent residual ASCVD risk despite aggressive LDL-C lowering.
CONTENT
Non-LDL-C lipid parameters, most notably triglycerides, triglyceride-rich lipoproteins (TGRLs), and lipoprotein(a), and C-reactive protein as a measure of inflammation are increasingly recognized as associated with residual risk after LDL-C lowering. Eicosapentaenoic acid in statin-treated patients with high triglycerides reduced both triglycerides and ASCVD events. Reducing TGRLs is believed to have beneficial effects on inflammation and atherosclerosis. High lipoprotein(a) concentrations increase ASCVD risk even in individuals with LDL-C < 70 mg/dL. Although statins do not generally lower lipoprotein(a), proprotein convertase subtilisin/kexin type 9 inhibitors reduce lipoprotein(a) and cardiovascular outcomes, and newer approaches are in development. Persistent increases in C-reactive protein after intensive lipid therapy have been consistently associated with increased risk for ASCVD events.
SUMMARY
We review the evidence that biochemical assays to measure TGRLs, lipoprotein(a), and C-reactive protein are associated with residual risk in patients treated to low concentrations of LDL-C. Growing evidence supports a causal role for TGRLs, lipoprotein(a), and inflammation in ASCVD; novel therapies that target TGRLs, lipoprotein(a), and inflammation are in development to reduce residual ASCVD risk.
Topics: Atherosclerosis; Biomarkers; C-Reactive Protein; Cholesterol, LDL; Heart Disease Risk Factors; Humans; Hypolipidemic Agents; Inflammation; Lipoprotein(a); Lipoproteins; Triglycerides
PubMed: 33257928
DOI: 10.1093/clinchem/hvaa252 -
Cell Cycle (Georgetown, Tex.) Jun 2022The maintenance of cellular cholesterol homeostasis is essential for normal cell function and viability. Excessive cholesterol accumulation is detrimental to cells and... (Review)
Review
The maintenance of cellular cholesterol homeostasis is essential for normal cell function and viability. Excessive cholesterol accumulation is detrimental to cells and serves as the molecular basis of many diseases, such as atherosclerosis, Alzheimer's disease, and diabetes mellitus. The peripheral cells do not have the ability to degrade cholesterol. Cholesterol efflux is therefore the only pathway to eliminate excessive cholesterol from these cells. This process is predominantly mediated by ATP-binding cassette transporter A1 (ABCA1), an integral membrane protein. ABCA1 is known to transfer intracellular free cholesterol and phospholipids to apolipoprotein A-I (apoA-I) for generating nascent high-density lipoprotein (nHDL) particles. nHDL can accept more free cholesterol from peripheral cells. Free cholesterol is then converted to cholesteryl ester by lecithin:cholesterol acyltransferase to form mature HDL. HDL-bound cholesterol enters the liver for biliary secretion and fecal excretion. Although how cholesterol is transported by ABCA1 to apoA-I remains incompletely understood, nine models have been proposed to explain this effect. In this review, we focus on the current view of the mechanisms underlying ABCA1-mediated cholesterol efflux to provide an important framework for future investigation and lipid-lowering therapy.
Topics: ATP Binding Cassette Transporter 1; Apolipoprotein A-I; Biological Transport; Cholesterol; Cholesterol, HDL; Lipoproteins, HDL; Phosphatidylcholine-Sterol O-Acyltransferase
PubMed: 35192423
DOI: 10.1080/15384101.2022.2042777 -
Cardiovascular Research Feb 2022The prothrombotic state in atrial fibrillation (AF) occurs as a result of multifaceted interactions, known as Virchow's triad of hypercoagulability, structural... (Review)
Review
The prothrombotic state in atrial fibrillation (AF) occurs as a result of multifaceted interactions, known as Virchow's triad of hypercoagulability, structural abnormalities, and blood stasis. More recently, there is emerging evidence that lipoproteins are implicated in this process, beyond their traditional role in atherosclerosis. In this review, we provide an overview of the various lipoproteins and explore the association between lipoproteins and AF, the effects of lipoproteins on haemostasis, and the potential contribution of lipoproteins to thrombogenesis in AF. There are several types of lipoproteins based on size, lipid composition, and apolipoprotein category, namely: chylomicrons, very low-density lipoprotein, low-density lipoprotein (LDL), intermediate-density lipoprotein, and high-density lipoprotein. Each of these lipoproteins may contain numerous lipid species and proteins with a variety of different functions. Furthermore, the lipoprotein particles may be oxidized causing an alteration in their structure and content. Of note, there is a paradoxical inverse relationship between total cholesterol and LDL cholesterol (LDL-C) levels, and incident AF. The mechanism by which this occurs may be related to the stabilizing effect of cholesterol on myocardial membranes, along with its role in inflammation. Overall, specific lipoproteins may interact with haemostatic pathways to promote excess platelet activation and thrombin generation, as well as inhibiting fibrinolysis. In this regard, LDL-C has been shown to be an independent risk factor for thromboembolic events in AF. The complex relationship between lipoproteins, thrombosis and AF warrants further research with an aim to improve our knowledge base and contribute to our overall understanding of lipoprotein-mediated thrombosis.
Topics: Atrial Fibrillation; Cholesterol, LDL; Humans; Lipoproteins; Lipoproteins, HDL; Lipoproteins, LDL; Thrombosis
PubMed: 33483737
DOI: 10.1093/cvr/cvab017 -
PLoS Biology Feb 2022Large-scale molecular profiling and genotyping provide a unique opportunity to systematically compare the genetically predicted effects of therapeutic targets on the...
Large-scale molecular profiling and genotyping provide a unique opportunity to systematically compare the genetically predicted effects of therapeutic targets on the human metabolome. We firstly constructed genetic risk scores for 8 drug targets on the basis that they primarily modify low-density lipoprotein (LDL) cholesterol (HMGCR, PCKS9, and NPC1L1), high-density lipoprotein (HDL) cholesterol (CETP), or triglycerides (APOC3, ANGPTL3, ANGPTL4, and LPL). Conducting mendelian randomisation (MR) provided strong evidence of an effect of drug-based genetic scores on coronary artery disease (CAD) risk with the exception of ANGPTL3. We then systematically estimated the effects of each score on 249 metabolic traits derived using blood samples from an unprecedented sample size of up to 115,082 UK Biobank participants. Genetically predicted effects were generally consistent among drug targets, which were intended to modify the same lipoprotein lipid trait. For example, the linear fit for the MR estimates on all 249 metabolic traits for genetically predicted inhibition of LDL cholesterol lowering targets HMGCR and PCSK9 was r2 = 0.91. In contrast, comparisons between drug classes that were designed to modify discrete lipoprotein traits typically had very different effects on metabolic signatures (for instance, HMGCR versus each of the 4 triglyceride targets all had r2 < 0.02). Furthermore, we highlight this discrepancy for specific metabolic traits, for example, finding that LDL cholesterol lowering therapies typically had a weak effect on glycoprotein acetyls, a marker of inflammation, whereas triglyceride modifying therapies assessed provided evidence of a strong effect on lowering levels of this inflammatory biomarker. Our findings indicate that genetically predicted perturbations of these drug targets on the blood metabolome can drastically differ, despite largely consistent effects on risk of CAD, with potential implications for biomarkers in clinical development and measuring treatment response.
Topics: Angiopoietin-Like Protein 3; Angiopoietin-like Proteins; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Humans; Lipoproteins; Mendelian Randomization Analysis; Proprotein Convertase 9; Triglycerides
PubMed: 35213538
DOI: 10.1371/journal.pbio.3001547 -
Journal of the American College of... Mar 2022Laboratory methods that report low-density lipoprotein cholesterol (LDL-C) include both LDL-C and lipoprotein(a) cholesterol [Lp(a)-C] content. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Laboratory methods that report low-density lipoprotein cholesterol (LDL-C) include both LDL-C and lipoprotein(a) cholesterol [Lp(a)-C] content.
OBJECTIVES
The purpose of this study was to assess the effect of pelacarsen on directly measured Lp(a)-C and LDL-C corrected for its Lp(a)-C content.
METHODS
The authors evaluated subjects with a history of cardiovascular disease and elevated Lp(a) randomized to 5 groups of cumulative monthly doses of 20-80 mg pelacarsen vs placebo. Direct Lp(a)-C was measured on isolated Lp(a) using LPA4-magnetic beads directed to apolipoprotein(a). LDL-C was reported as: 1) LDL-C as reported by the clinical laboratory; 2) LDL-C = laboratory-reported LDL-C - direct Lp(a)-C; and 3) LDL-C = laboratory LDL-C - [Lp(a) mass × 0.30] estimated by the Dahlén formula.
RESULTS
The baseline median Lp(a)-C values in the groups ranged from 11.9 to 15.6 mg/dL. Compared with placebo, pelacarsen resulted in dose-dependent decreases in Lp(a)-C (2% vs -29% to -67%; P = 0.001-<0.0001). Baseline laboratory-reported mean LDL-C ranged from 68.5 to 89.5 mg/dL, whereas LDL-C ranged from 55 to 74 mg/dL. Pelacarsen resulted in mean percent/absolute changes of -2% to -19%/-0.7 to -8.0 mg/dL (P = 0.95-0.05) in LDL-C, -7% to -26%/-5.4 to -9.4 mg/dL (P = 0.44-<0.0001) in laboratory-reported LDL-C, and 3.1% to 28.3%/0.1 to 9.5 mg/dL (P = 0.006-0.50) increases in LDL-C. Total apoB declined by 3%-16% (P = 0.40-<0.0001), but non-Lp(a) apoB was not significantly changed.
CONCLUSIONS
Pelacarsen significantly lowers direct Lp(a)-C and has neutral to mild lowering of LDL-C. In patients with elevated Lp(a), LDL-C provides a more accurate reflection of changes in LDL-C than either laboratory-reported LDL-C or the Dahlén formula.
Topics: Apolipoproteins A; Cholesterol; Cholesterol, LDL; Humans; Lipoprotein(a); Oligonucleotides, Antisense
PubMed: 35300814
DOI: 10.1016/j.jacc.2021.12.032 -
Medicinal Research Reviews Jan 2020Inflammation is thought to play an important role in the pathogenesis of vascular diseases. Lipoprotein-associated phospholipase A2 (Lp-PLA2) mediates vascular... (Review)
Review
Inflammation is thought to play an important role in the pathogenesis of vascular diseases. Lipoprotein-associated phospholipase A2 (Lp-PLA2) mediates vascular inflammation through the regulation of lipid metabolism in blood, thus, it has been extensively investigated to identify its role in vascular inflammation-related diseases, mainly atherosclerosis. Although darapladib, the most advanced Lp-PLA2 inhibitor, failed to meet the primary endpoints of two large phase III trials in atherosclerosis patients cotreated with standard medical care, the research on Lp-PLA2 has not been terminated. Novel pathogenic, epidemiologic, genetic, and crystallographic studies regarding Lp-PLA2 have been reported recently, while novel inhibitors were identified through a fragment-based lead discovery strategy. More strikingly, recent clinical and preclinical studies revealed that Lp-PLA2 inhibition showed promising therapeutic effects in diabetic macular edema and Alzheimer's disease. In this review, we not only summarized the knowledge of Lp-PLA2 established in the past decades but also emphasized new findings in recent years. We hope this review could be valuable for helping researchers acquire a much deeper insight into the nature of Lp-PLA2, identify more potent and selective Lp-PLA2 inhibitors, and discover the potential indications of Lp-PLA2 inhibitors.
Topics: 1-Alkyl-2-acetylglycerophosphocholine Esterase; Animals; Disease; Genetic Variation; Humans; Lipoproteins; Small Molecule Libraries; Substrate Specificity
PubMed: 31140638
DOI: 10.1002/med.21597 -
Global Heart 2022Atherosclerotic cardiovascular diseases (ASCVD) including myocardial infarction, stroke and peripheral arterial disease continue to be major causes of premature death,... (Review)
Review
BACKGROUND
Atherosclerotic cardiovascular diseases (ASCVD) including myocardial infarction, stroke and peripheral arterial disease continue to be major causes of premature death, disability and healthcare expenditure globally. Preventing the accumulation of cholesterol-containing atherogenic lipoproteins in the vessel wall is central to any healthcare strategy to prevent ASCVD. Advances in current concepts about reducing cumulative exposure to apolipoprotein B (apo B) cholesterol-containing lipoproteins and the emergence of novel therapies provide new opportunities to better prevent ASCVD. The present update of the World Heart Federation Cholesterol Roadmap provides a conceptual framework for the development of national policies and health systems approaches, so that potential roadblocks to cholesterol management and thus ASCVD prevention can be overcome.
METHODS
Through a review of published guidelines and research papers since 2017, and consultation with a committee composed of experts in clinical management of dyslipidaemias and health systems research in low-and-middle income countries (LMICs), this Roadmap identifies (1) key principles to effective ASCVD prevention (2) gaps in implementation of these interventions (knowledge-practice gaps); (3) health system roadblocks to treatment of elevated cholesterol in LMICs; and (4) potential strategies for overcoming these.
RESULTS
Reducing the future burden of ASCVD will require diverse approaches throughout the life-course. These include: a greater focus on primordial prevention; availability of affordable cholesterol testing; availability of universal cholesterol screening for inherited dyslipidaemias; risk stratification moving beyond 10-year risk to look at lifetime risk with adequate risk estimators; wider availability of affordable cholesterol-lowering therapies which should include statins as essential medications globally; use of adequate doses of potent statin regimens; and combination therapies with ezetimibe or other therapies in order to attain and maintain robust reductions in LDL-C in those at highest risk. Continuing efforts are needed on health literacy for both the public and healthcare providers, utilising multi-disciplinary teams in healthcare and applications that quantify both ASCVD risk and benefits of treatment as well as increased adherence to therapies.
CONCLUSIONS
The adverse effects of LDL-cholesterol and apo B containing lipoprotein exposure are cumulative and result in ASCVD. These are preventable by implementation of different strategies, aimed at efficiently tackling atherosclerosis at different stages throughout the human life-course. Preventive strategies should therefore be updated to implement health policy, lifestyle changes and when needed pharmacotherapies earlier with investment in, and a shift in focus towards, early preventive strategies that preserve cardiovascular health rather than treat the consequences of ASCVD.
Topics: Humans; Cholesterol; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Dyslipidemias; Atherosclerosis; Lipoproteins; Apolipoproteins B; Cardiovascular Diseases
PubMed: 36382159
DOI: 10.5334/gh.1154 -
European Heart Journal Apr 2023Previous interest in high-density lipoproteins (HDLs) focused on their possible protective role in atherosclerotic cardiovascular disease (ASCVD). Evidence from genetic... (Review)
Review
Previous interest in high-density lipoproteins (HDLs) focused on their possible protective role in atherosclerotic cardiovascular disease (ASCVD). Evidence from genetic studies and randomized trials, however, questioned that the inverse association of HDL-cholesterol (HDL-C) is causal. This review aims to provide an update on the role of HDL in health and disease, also beyond ASCVD. Through evolution from invertebrates, HDLs are the principal lipoproteins, while apolipoprotein B-containing lipoproteins first developed in vertebrates. HDLs transport cholesterol and other lipids between different cells like a reusable ferry, but serve many other functions including communication with cells and the inactivation of biohazards like bacterial lipopolysaccharides. These functions are exerted by entire HDL particles or distinct proteins or lipids carried by HDL rather than by its cholesterol cargo measured as HDL-C. Neither does HDL-C measurement reflect the efficiency of reverse cholesterol transport. Recent studies indicate that functional measures of HDL, notably cholesterol efflux capacity, numbers of HDL particles, or distinct HDL proteins are better predictors of ASCVD events than HDL-C. Low HDL-C levels are related observationally, but also genetically, to increased risks of infectious diseases, death during sepsis, diabetes mellitus, and chronic kidney disease. Additional, but only observational, data indicate associations of low HDL-C with various autoimmune diseases, and cancers, as well as all-cause mortality. Conversely, extremely high HDL-C levels are associated with an increased risk of age-related macular degeneration (also genetically), infectious disease, and all-cause mortality. HDL encompasses dynamic multimolecular and multifunctional lipoproteins that likely emerged during evolution to serve several physiological roles and prevent or heal pathologies beyond ASCVD. For any clinical exploitation of HDL, the indirect marker HDL-C must be replaced by direct biomarkers reflecting the causal role of HDL in the respective disease.
Topics: Animals; Humans; Lipoproteins, HDL; Clinical Relevance; Cholesterol; Cholesterol, HDL; Lipoproteins; Atherosclerosis
PubMed: 36337032
DOI: 10.1093/eurheartj/ehac605 -
European Heart Journal Jul 2023Due to growing environmental focus, plant-based diets are increasing steadily in popularity. Uncovering the effect on well-established risk factors for cardiovascular... (Meta-Analysis)
Meta-Analysis
AIMS
Due to growing environmental focus, plant-based diets are increasing steadily in popularity. Uncovering the effect on well-established risk factors for cardiovascular diseases, the leading cause of death worldwide, is thus highly relevant. Therefore, a systematic review and meta-analysis were conducted to estimate the effect of vegetarian and vegan diets on blood levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and apolipoprotein B.
METHODS AND RESULTS
Studies published between 1980 and October 2022 were searched for using PubMed, Embase, and references of previous reviews. Included studies were randomized controlled trials that quantified the effect of vegetarian or vegan diets vs. an omnivorous diet on blood lipids and lipoprotein levels in adults over 18 years. Estimates were calculated using a random-effects model. Thirty trials were included in the study. Compared with the omnivorous group, the plant-based diets reduced total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B levels with mean differences of -0.34 mmol/L (95% confidence interval, -0.44, -0.23; P = 1 × 10-9), -0.30 mmol/L (-0.40, -0.19; P = 4 × 10-8), and -12.92 mg/dL (-22.63, -3.20; P = 0.01), respectively. The effect sizes were similar across age, continent, duration of study, health status, intervention diet, intervention program, and study design. No significant difference was observed for triglyceride levels.
CONCLUSION
Vegetarian and vegan diets were associated with reduced concentrations of total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B-effects that were consistent across various study and participant characteristics. Plant-based diets have the potential to lessen the atherosclerotic burden from atherogenic lipoproteins and thereby reduce the risk of cardiovascular disease.
Topics: Adult; Humans; Diet, Vegan; Diet, Vegetarian; Randomized Controlled Trials as Topic; Lipids; Vegetarians; Cholesterol, LDL; Lipoproteins; Cardiovascular Diseases; Atherosclerosis; Apolipoproteins
PubMed: 37226630
DOI: 10.1093/eurheartj/ehad211 -
Journal of the American College of... May 2023Lipoprotein(a) (Lp[a]) and oxidized phospholipids (OxPLs) are each independent risk factors for atherosclerotic cardiovascular disease. The extent to which Lp(a) and...
BACKGROUND
Lipoprotein(a) (Lp[a]) and oxidized phospholipids (OxPLs) are each independent risk factors for atherosclerotic cardiovascular disease. The extent to which Lp(a) and OxPLs predict coronary artery disease (CAD) severity and outcomes in a contemporary, statin-treated cohort is not well established.
OBJECTIVES
This study sought to evaluate the relationships between Lp(a) particle concentration and OxPLs associated with apolipoprotein B (OxPL-apoB) or apolipoprotein(a) (OxPL-apo[a]) with angiographic CAD and cardiovascular outcomes.
METHODS
Among 1,098 participants referred for coronary angiography in the CASABLANCA (Catheter Sampled Blood Archive in Cardiovascular Diseases) study, Lp(a), OxPL-apoB, and OxPL-apo(a) were measured. Logistic regression estimated the risk of multivessel coronary stenoses by Lp(a)-related biomarker level. Cox proportional hazards regression estimated the risk of major adverse cardiovascular events (MACEs) (coronary revascularization, nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death) in follow-up.
RESULTS
Median Lp(a) was 26.45 nmol/L (IQR: 11.39-89.49 nmol/L). Lp(a), OxPL-apoB, and OxPL-apo(a) were highly correlated (Spearman R ≥0.91 for all pairwise combinations). Lp(a) and OxPL-apoB were associated with multivessel CAD. Odds of multivessel CAD per doubling of Lp(a), OxPL-apoB, and OxPL-apo(a) were 1.10 (95% CI: 1.03-1.18; P = 0.006), 1.18 (95% CI: 1.03-1.34; P = 0.01), and 1.07 (95% CI: 0.99-1.16; P = 0.07), respectively. All biomarkers were associated with cardiovascular events. HRs for MACE per doubling of Lp(a), OxPL-apoB, and OxPL-apo(a) were 1.08 (95% CI: 1.03-1.14; P = 0.001), 1.15 (95% CI: 1.05-1.26; P = 0.004), and 1.07 (95% CI: 1.01-1.14; P = 0.02), respectively.
CONCLUSIONS
In patients undergoing coronary angiography, Lp(a) and OxPL-apoB are associated with multivessel CAD. Lp(a), OxPL-apoB, and OxPL-apo(a) are associated with incident cardiovascular events. (Catheter Sampled Blood Archive in Cardiovascular Diseases [CASABLANCA]; NCT00842868).
Topics: Humans; Coronary Artery Disease; Lipoprotein(a); Cardiovascular Diseases; Phospholipids; Apolipoproteins B; Apolipoproteins A; Biomarkers; Apoprotein(a); Oxidation-Reduction
PubMed: 37137588
DOI: 10.1016/j.jacc.2023.02.050