Mechanism of action of niacin

Reduction in Secretion of Very Low Density Lipoprotein-Triacylglycerol by a Matrix Metalloproteinase Inhibitor in a Rat Model of Diet-Induced Hypertriglyceridemia

Matrix metalloproteinase inhibitors (MMPIs) reduced serum triacylglycerol (TAG) levels in streptozotocin-induced diabetic rats and Zucker fa/fa rats in our previous study. However, the mechanisms underlying TAG reduction by MMPIs remain unclear. The present study aimed to elucidate the mechanism by which F81-1144b, an MMPI, lowers serum TAG levels in an animal model of high-sucrose diet (HSD)-induced hypertriglyceridemia. F81-1144b was repeatedly administered to rats fed HSD, and its effects were evaluated on TAG levels in serum and the liver, very low density lipoprotein (VLDL) secretion, de novo fatty acid (FA) synthesis in the liver, and the expression of genes regulating the metabolism of FA, TAG, and VLDL in the liver and serum. F81-1144b lowered TAG levels in serum and the liver, VLDL-TAG secretion, de novo FA synthesis in the liver, and serum levels of insulin and glucose. F81-1144b suppressed the expression of genes related to the de novo synthesis of FA and TAG, key proteins (lipin 1 and apolipoprotein CIII) responsible for VLDL metabolism, and sterol regulatory element-binding protein-1c and carbohydrate response element-binding protein. F81-1144b little affected the expression of genes related directly to the degradation of TAG or FA, but it upregulated that of gene for uncoupling protein 2 in the liver. These results suggest that MMPIs are a novel type of therapeutic agent for the treatment of hypertriglyceridemia, because the metabolic effects of F81-1144b expected from changes in the expression of genes regulating lipid metabolism would alter metabolism differently from those induced by fibrates, niacin, or n-3 FAs.

Pharmacological treatment options for severe hypertriglyceridemia and familial chylomicronemia syndrome

INTRODUCTION

A spectrum of disorders, ranging from rare severe cases of homozygous null lipoprotein lipase deficiency (LPLD)-familial chylomicronemia syndrome (FCS) to heterozygous missense LPLD or polygenic causes, result in hypertriglyceridemia and pancreatitis. The effects of mutations are exacerbated by environmental factors such as diet, pregnancy, and insulin resistance. Areas covered: In this review, authors discuss chronic treatment of FCS by ultra-low fat diets allied with the use of fibrates, omega-3 fatty acids, niacin, statins, and insulin-sensitizing therapies depending on the extent of residual lipoprotein lipase (LPL) activity; novel therapies in development target triglyceride (TG)-rich lipoprotein particle clearance. Previously, a gene therapy approach to LPL-alipogene tiparvovec showed that direct targeting of LPL function reduced pancreatitis events. An antisense oligonucleotide to apolipoprotein-C3, volanesorsen has been shown to decrease TGs by 70-80% and possibly to reduce rates of pancreatitis admissions. Studies are underway to validate its long-term efficacy and safety. Other approaches investigating the role of LPL modulating proteins such as angiopoietin-like petide-3 (ANGPTL3) are under consideration. Expert opinion: Current therapeutic options are not sufficient for management of many cases of FCS. The availability of antisense anti-apoC3 therapies and, in the future, ANGPTL3 therapies may remedy this.

Drugs Involved in Dyslipidemia and Obesity Treatment: Focus on Adipose Tissue

Metabolic syndrome can be defined as a state of disturbed metabolic homeostasis characterized by visceral obesity, atherogenic dyslipidemia, arterial hypertension, and insulin resistance. The growing prevalence of metabolic syndrome will certainly contribute to the burden of cardiovascular disease. Obesity and dyslipidemia are main features of metabolic syndrome, and both can present with adipose tissue dysfunction, involved in the pathogenic mechanisms underlying this syndrome. We revised the effects, and underlying mechanisms, of the current approved drugs for dyslipidemia and obesity (fibrates, statins, niacin, resins, ezetimibe, and orlistat; sibutramine; and diethylpropion, phentermine/topiramate, bupropion and naltrexone, and liraglutide) on adipose tissue. Specifically, we explored how these drugs can modulate the complex pathways involved in metabolism, inflammation, atherogenesis, insulin sensitivity, and adipogenesis. The clinical outcomes of adipose tissue modulation by these drugs, as well as differences of major importance for clinical practice between drugs of the same class, were identified. Whether solutions to these issues will be found in further adjustments and combinations between drugs already in use or necessarily in new advances in pharmacology is not known. To better understand the effect of drugs used in dyslipidemia and obesity on adipose tissue not only is challenging for physicians but could also be the next step to tackle cardiovascular disease.

Dyslipidemias and Cardiovascular Prevention: Tailoring Treatment According to Lipid Phenotype

PURPOSE OF REVIEW

This study aimed to present the current information on the genetic background of dyslipidemias and provide insights into the complex pathophysiological role of several plasma lipids/lipoproteins in the pathogenesis of atherosclerotic cardiovascular disease. Furthermore, we aim to summarize established therapies and describe the scientific rationale for the development of novel therapeutic strategies.

RECENT FINDINGS

Evidence from genetic studies suggests that besides lowering low-density lipoprotein cholesterol, pharmacological reduction of triglyceride-rich lipoproteins, or lipoprotein(a) will reduce risk for coronary heart disease. Dyslipidemia, in particular hypercholesterolemia, is a common clinical condition and represents an important determinant of atherosclerotic vascular disease. Treatment decisions are currently guided by the causative lipid phenotype and the presence of other risk factors suggesting a very high cardiovascular risk. Therefore, the identification of lipid disorders and the optimal combination of therapeutic strategies provide an outstanding opportunity for reducing the onset and burden of cardiovascular disease.

Targeting the gut barrier for the treatment of alcoholic liver disease

Alcohol consumption remains one of the predominant causes of liver disease and liver-related death worldwide. Intriguingly, dysregulation of the gut barrier is a key factor promoting the pathogenesis of alcoholic liver disease (ALD). A functional gut barrier, which consists of a mucus layer, an intact epithelial monolayer and mucosal immune cells, supports nutrient absorption and prevents bacterial penetration. Compromised gut barrier function is associated with the progression of ALD. Indeed, alcohol consumption disrupts the gut barrier, increases gut permeability, and induces bacterial translocation both in ALD patients and in experimental models with ALD. Moreover, alcohol consumption also causes enteric dysbiosis with both numerical and proportional perturbations. Here, we review and discuss mechanisms of alcohol-induced gut barrier dysfunction to better understand the contribution of the gut-liver axis to the pathogenesis of ALD. Unfortunately, there is no effectual Food and Drug Administration-approved treatment for any stage of ALD. Therefore, we conclude with a discussion of potential strategies aimed at restoring the gut barrier in ALD. The principle behind antibiotics, prebiotics, probiotics and fecal microbiota transplants is to restore microbial symbiosis and subsequently gut barrier function. Nutrient-based treatments, such as dietary supplementation with zinc, niacin or fatty acids, have been shown to regulate tight junction expression, reduce intestinal inflammation, and prevent endotoxemia as well as liver injury caused by alcohol in experimental settings. Interestingly, saturated fatty acids may also directly control the gut microbiome. In summary, clinical and experimental studies highlight the significance and efficacy of the gut barrier in treating ALD.

Dyslipidaemia in nephrotic syndrome: mechanisms and treatment

Nephrotic syndrome is a highly prevalent disease that is associated with high morbidity despite notable advances in its treatment. Many of the complications of nephrotic syndrome, including the increased risk of atherosclerosis and thromboembolism, can be linked to dysregulated lipid metabolism and dyslipidaemia. These abnormalities include elevated plasma levels of cholesterol, triglycerides and the apolipoprotein B-containing lipoproteins VLDL and IDL; decreased lipoprotein lipase activity in the endothelium, muscle and adipose tissues; decreased hepatic lipase activity; and increased levels of the enzyme PCSK9. In addition, there is an increase in the plasma levels of immature HDL particles and reduced cholesterol efflux. Studies from the past few years have markedly improved our understanding of the molecular pathogenesis of nephrotic syndrome-associated dyslipidaemia, and also heightened our awareness of the associated exacerbated risks of cardiovascular complications, progressive kidney disease and thromboembolism. Despite the absence of clear guidelines regarding treatment, various strategies are being increasingly utilized, including statins, bile acid sequestrants, fibrates, nicotinic acid and ezetimibe, as well as lipid apheresis, which seem to also induce partial or complete clinical remission of nephrotic syndrome in a substantial percentage of patients. Future potential treatments will likely also include inhibition of PCSK9 using recently-developed anti-PCSK9 monoclonal antibodies and small inhibitory RNAs, as well as targeting newly identified molecular regulators of lipid metabolism that are dysregulated in nephrotic syndrome.

Maternal high calorie diet induces mitochondrial dysfunction and senescence phenotype in subcutaneous fat of newborn mice

Mitochondrial dysfunction, inflammation and senescence-like features are observed in adipose depots in aging and obesity. Herein, we evaluated how maternal high calorie diet (HCD) may impact on subcutaneous adipose tissue (sAT) of the newborn mice. Adult C57BL/6J mice were randomly divided in three groups: normal calorie diet (NCD), HCD and HCD supplemented with niacin 8 weeks before mating. Mothers and pups were then sacrificed and metabolic and molecular analyses were carried out on sAT. HCD induced mitochondria dysfunction in mothers without inflammation and senescence, whereas in pups we also revealed the occurrence of senescent phenotype. The mitochondrial dysfunction-associated senescence in pups was accompanied by a drop in NAD⁺/NADH ratio and alteration in the NAD⁺-dependent enzymes PARP1 and SIRT1. Importantly, maternal dietary supplementation with niacin during gestation and lactation restrained NAD⁺/NADH decrease imposed by HCD limiting inflammatory cytokine production and senescence phenotype in newborn sAT. Given the fundamental role of sAT in buffering nutrient overload and avoiding pathogenic ectopic fat accumulation, we suggest that NAD⁺ boosting strategies during maternal HCD could be helpful in limiting sAT dysfunction in newborn.

Anti-Atherosclerotic Action of Agmatine in ApoE-Knockout Mice

Atherosclerosis is an inflammatory disease in which dysfunction of mitochondria play an important role, and disorders of lipid management intensify this process. Agmatine, an endogenous polyamine formed by decarboxylation of arginine, exerts a protective effect on mitochondria and modulates fatty acid metabolism. We investigated the effect of exogenous agmatine on the development of atherosclerosis and changes in lipid profile in apolipoprotein E knockout (apoE-/-) mice. Agmatine caused an approximate 40% decrease of atherosclerotic lesions, as estimated by en face and cross-section methods with an influence on macrophage but not on smooth muscle content in the plaques. Agmatine treatment did not changed gelatinase activity within the plaque area. What is more, the action of agmatine was associated with an increase in the number of high density lipoproteins (HDL) in blood. Real-Time PCR analysis showed that agmatine modulates liver mRNA levels of many factors involved in oxidation of fatty acid and cholesterol biosynthesis. Two-dimensional electrophoresis coupled with mass spectrometry identified 27 differentially expressed mitochondrial proteins upon agmatine treatment in the liver of apoE-/- mice, mostly proteins related to metabolism and apoptosis. In conclusion, prolonged administration of agmatine inhibits atherosclerosis in apoE-/- mice; however, the exact mechanisms linking observed changes and elevations of HDL plasma require further investigation.

Association of Some Vitamins and Minerals with Periodontitis in a Nationally Representative Sample of Korean Young Adults

The purpose of this study was to investigate whether the intakes of some kinds of vitamins and minerals are associated with periodontitis in a nationally representative sample of young adults. This study comprised 2049 young adults aged 19-39 years who took both periodontal examination and nutrition survey. The vitamin and mineral intakes were calculated from dietary intake data gained by complete one-day 24-h recall interviews, and the intake levels for each nutrient were classified by the Recommended Nutrient Intake (RNI) in Dietary Reference Intakes for Koreans and median values. Periodontitis was assessed using Community Periodontal Index (CPI). Multivariate logistic regression analyses were performed in a whole sample and subgroups with the strata of gender or smoking, following a complex sampling design. In analyses according to RNI, a lower intake of niacin was significantly associated with periodontitis in young adults (odd ratio [OR] 1.47, 95% confidential interval [CI] 1.09-2.00) and in its subgroup of women (OR 1.70; 95% CI 1.10-2.64) and current non-smokers (OR 1.75; 95% CI 1.22-2.51). Whereas, in analyses according to median intake values, there were significant associations of periodontitis with a lower intake of niacin in women (OR 1.58; 95% CI 1.02-2.46) and current non-smokers (OR 1.50; 95% CI 1.01-2.22), with lower intake of vitamin C in women (OR 1.66; 95% CI 1.04-2.64) and in current non-smokers (OR 1.49; 95% CI 1.04-2.14), with lower intake of iron in women (OR 1.85; 95% CI 1.11-3.07), and with lower intake of vitamin A marginally in women (OR 1.56; 95% CI 1.00-2.44). In young adults, periodonitis is significantly associated with the lower intakes of niacin, vitamin C, and iron, especially in women and current non-smokers.

Genetic coding variants in the niacin receptor, hydroxyl-carboxylic acid receptor 2, and response to niacin therapy

OBJECTIVE

Niacin has been used for seven decades to modulate plasma lipids, but its mechanism of action is still unclear. We sought to determine whether variants in the niacin receptor gene, hydroxyl-carboxylic receptor 2 (HCAR2), are associated with lipid response to treatment.

PARTICIPANTS AND METHODS

Coding variants, rs7314976 (p.R311C) and rs2454727 (p.M317I), were genotyped in 2067 participants from the Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides and Impact on Global Health Outcomes (AIM-HIGH) trial. AIM-HIGH was a randomized, placebo-controlled trial that was conducted to assess the effect of extended-release niacin in patients with cardiovascular disease aggressively treated with low-density lipoprotein cholesterol-lowering therapy.

RESULTS

There was no association of p.R311C or p.M317I with changes in low-density lipoprotein cholesterol, triglycerides, or high-density lipoprotein cholesterol at 1 year in groups receiving placebo or extended-release niacin. In White patients, the reduction in lipoprotein (a) [Lp(a)] in response to niacin was greater in homozygous carriers of the major 317M allele (-22.7%; P=0.005) compared with minor allele carriers (-15.3%). This was directionally consistent in the Black participants. Upon combining both groups, the reduction in Lp(a) in response to niacin was significantly greater in the homozygous major allele carriers (-23.0%; P=0.003) compared with minor allele carriers (-15.2%).

CONCLUSION

Understanding the genetic contribution toward variation in response to niacin therapy, including Lp(a) reduction, could uncover mechanisms by which niacin decreases Lp(a), an important independent risk factor for cardiovascular disease.

Nutritional interventions for Alzheimer's prevention: a clinical precision medicine approach

Alzheimer's disease (AD) is a major source of morbidity and mortality, with the disease burden expected to rise as the population ages. No disease-modifying agent is currently available, but recent research suggests that nutritional and lifestyle modifications can delay or prevent the onset of AD. However, preventive nutritional interventions are not universally applicable and depend on the clinical profile of the individual patient. This article reviews existing nutritional modalities for AD prevention that act through improvement of insulin resistance, correction of dyslipidemia, and reduction of oxidative stress, and discusses how they may be modified on the basis of individual biomarkers, genetics, and behavior. In addition, we report preliminary results of clinical application of these personalized interventions at the first AD prevention clinic in the United States. The use of these personalized interventions represents an important application of precision medicine techniques for the prevention of AD that can be adopted by clinicians across disciplines.

Plasma Lipidome Analysis by Liquid Chromatography-High Resolution Mass Spectrometry and Ion Mobility of Hypertriglyceridemic Patients on Extended-Release Nicotinic Acid: a Pilot Study

BACKGROUND

Plasma high triacylglycerols and low HDL-C concentration are associated with increased cardiovascular events. Extended-release nicotinic acid (ERN) was shown to reduce plasma triacylglycerols and total cholesterol but also to markedly increase high-density lipoprotein-cholesterol (HDL-C). No data on the effect of ERN on different species of triacylglycerol, cholesteryl ester, and phospholipids are available. In this study, we applied a nontargeted lipidomic approach to investigate the plasma and lipoproteins lipids profile of hypertriglyceridemic patients treated with ERN or a placebo in order to identify new lipids markers associated with this treatment.

METHODS

Eight hypertriglyceridemic patients enrolled in a crossover randomized trial with ERN for 8 weeks and treated with 2 g/day of ERN or a placebo. Ultra-performance liquid chromatography (UPLC) coupled to high-resolution mass spectrometry (HRMS) was used in mass spectrometry energy mode (HRMSE) combined with ion mobility spectrometry to characterize the plasma and very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) lipidome. The accuracy and precision of the method were validated on plasma samples.

RESULTS

Compared to placebo, among 155 plasma lipids characterized using UPLC-ESI-HRMS, a multivariate analysis revealed a significant increase of lysophosphatidylcholine (LPC 20:5), a significant decrease of phosphatidylethanolamine (PE 16:0/22:3) and sphingomyelin (SM d18:1/22:0) and a decrease of triacylglycerol (TG 16:0/16:1/18:2) after ERN treatment. Analysis of these lipids in lipoproteins showed an increase of LPC (20:5) in HDL, a decrease of PE (16:0/22:3) in HDL and LDL, of SM (d18:1/22:0) in VLDL and LDL and of TG (16:0/16:1/18:2) in VLDL.

CONCLUSION

This lipidomic strategy characterized new specific lipid markers likely to be involved in the effect of ERN on cardiovascular risk opening a new strategy to analyze randomized controlled with this treatment.

TRIAL REGISTRATION

NCT01216956.

2017 Position Paper of the Italian Society for Cardiovascular Prevention (SIPREC) for an Updated Clinical Management of Hypercholesterolemia and Cardiovascular Risk: Executive Document

The benefits achieved by implementing cardiovascular prevention strategies in terms of reduced incidence of atherosclerotic diseases and mortality are accepted, worldwide. In particular, the clinical management of hypercholesterolemia has a fundamental role for all preventive strategies, both in primary and secondary prevention, at each stage of cardiovascular risk. Since the net clinical benefit of lipid-lowering therapy largely depends on baseline individual cardiovascular risk profile, the assessment of individual risk is essential to establish type and intensity of both preventive and therapeutic strategies. Thus, the real challenge in a setting of clinical practice is not only to identify whom to treat among individuals at low-to-moderate risk, but mostly how much and how long to treat high or very-high risk patients. This manuscript, which reflects concepts and positions that have been published in a more extensive document of the Italian Society for Cardiovascular Prevention (SIPREC), deals with the diagnostic and therapeutic management of patients with dyslipidaemia, with an evidence-based approach adapted and updated from recent guidelines of the European Society of Cardiology and very recent results of randomized clinical trials. The purpose is to suggest a multidimensional and integrated actions aimed at eliminating or minimizing the impact of cardiovascular diseases and their related disabilities and mortality in patients with hypercholesterolemia.

Oral β-hydroxybutyrate increases ketonemia, decreases visceral adipocyte volume and improves serum lipid profile in Wistar rats

Background

Ketosis can be induced in humans and in animals by fasting or dietary interventions, such as ketogenic diets. However, the increasing interest on the ketogenic state has motivated the development of alternative approaches to rapidly increase ketonemia using less drastic interventions. Here, it was tested whether oral intake of a β-hydroxybutyrate (βHB) mineral salt mixture could increase ketonemia in Wistar rats without any other dietary changes, thereby being a useful model to study ketones effects alone on metabolism.

Methods

βHB salts were orally administered to provoke elevation in the ketonemia. Effects of this intervention were tested acutely (by gavage) and chronically (4 weeks in drinking water). Acutely, a concomitant glucose overload was used to suppress endogenous ketogenesis and verify whether βHB salts were really absorbed or not. Long-term administration allowed to weekly evaluate the impact on ketonemia, blood glucose and, after 4 weeks, on body weight, visceral fat mass, lipid blood profile, serum lipolysis products and adiponectinemia.

Results

βHB salts increased ketonemia in acute and long-term administrations, improved blood lipid profile by raising HDL-cholesterol concentration and decreasing LDL/HDL ratio, while reduced visceral adipocyte volume. Mean ketonemia correlated positively with HDLc and negatively with adipocyte volume and serum lipolysis products.

Conclusions

Oral βHB can rapidly increase ketonemia and, therefore, be used as an acute and long-term animal model of ketosis. Long-term treatment points to important beneficial effects of ketone bodies in serum lipid concentrations and visceral fat mass. These results may help to explain the metabolic adaptations following ketogenic diets, such as a better body fat control and a serum lipid profile improvement.

Role of Niacin in Current Clinical Practice: A Systematic Review

BACKGROUND

Niacin, a potent high-density lipoprotein cholesterol-raising drug, seems an attractive approach to reduce cardiac events in patients with or at risk of atherosclerotic cardiovascular disease. However, previous evidence for niacin has been challenged recently by negative outcomes in 2 large, randomized, controlled trials comparing niacin to placebo with background statin therapy. We studied the currently available evidence for the role of niacin treatment for reducing the risk of cardiovascular events in current practice.

METHODS

A systematic review of randomized controlled trials in the MEDLINE, EMBASE, CINAHL, and Cochrane databases comparing niacin alone or combined with statin therapy was performed. We extracted trial level data, including basic characteristics and number of patients enrolled, duration of follow up, occurrence of adverse events, and cardiovascular-related outcomes. Random effects meta-analysis was conducted to estimate the risk ratio (RR) for individual trial endpoints.

RESULTS

Thirteen trials (N = 35,206) were selected for final analysis. The mean follow-up duration was 32.8 months. Overall, niacin led to significant increases in serum high-density lipoprotein cholesterol levels from baseline trial enrolment by 21.4%, 9.31 (95% confidence interval [CI] 5.11-13.51) mg/dL. However, we did not observe any differences in all-cause mortality rates (RR 0.99; 95% CI 0.88-1.12) between niacin and control arms. Further, niacin treatment was associated with a trend toward lower risk of cardiovascular mortality (RR 0.91; 95% CI 0.81-1.02), coronary death (RR 0.93; 95% CI 0.78-1.10), nonfatal myocardial infarction (RR 0.85; 95% CI 0.73-1.0), revascularization (coronary and noncoronary) (RR 0.83; 95% CI 0.65-1.06), and stroke (RR 0.89; 95% CI 0.72-1.10), compared with control.

CONCLUSION

Niacin therapy does not lead to significant reductions in total or cause-specific mortality or recurrent cardiovascular events among persons with or at risk of atherosclerotic cardiovascular disease.

Pleiotropic effects of niacin: Current possibilities for its clinical use

Niacin was the first hypolipidemic drug to significantly reduce both major cardiovascular events and mortality in patients with cardiovascular disease. Niacin favorably influences all lipoprotein classes, including lipoprotein[a],and belongs to the most potent hypolipidemic drugs for increasing HDL-C. Moreover, niacin causes favorable changes to the qualitative composition of lipoprotein HDL. In addition to its pronounced hypolipidemic action, niacin exerts many other, non-hypolipidemic effects (e.g., antioxidative, anti-inflammatory, antithrombotic), which favorably influence the development and progression of atherosclerosis. These effects are dependent on activation of the specific receptor HCA2. Recent results published by the two large clinical studies, AIM-HIGH and HPS2-THRIVE, have led to the impugnation of niacin's role in future clinical practice. However, due to several methodological flaws in the AIM-HIGH and HPS2-THRIVE studies, the pleiotropic effects of niacin now deserve thorough evaluation. This review summarizes the present and possible future use of niacin in clinical practice in light of its newly recognized pleiotropic effects.

Lipoprotein(a) in postmenopausal women: assessment of cardiovascular risk and therapeutic options

INTRODUCTION

Lipoprotein(a) [Lp(a)], a low-density lipoprotein (LDL)-like particle, has been independently associated with increased cardiovascular disease (CVD) risk in various populations, such as postmenopausal women. The purpose of this narrative review is to present current data on the role of Lp(a) in augmenting CVD risk in postmenopausal women and focus on the available therapeutic strategies.

METHODS

PubMed was searched for English language publications until November 2015 under the following terms: "therapy" OR "treatment" AND ["lipoprotein (a)" OR "Lp(a)"] AND ("postmenopausal women" OR "menopausal women" OR "menopause").

RESULTS

Only hormone replacement therapy (mainly oral estrogens) and tibolone have been specifically studied in postmenopausal women and can reduce Lp(a) concentrations by up to 44%, although evidence indicating a concomitant reduction in CVD risk associated with Lp(a) is lacking. As alternative treatments for women who cannot, or will not, take hormonal therapies, niacin and the upcoming proprotein convertase subtilisin / kexin type 9 (PCSK-9) inhibitors are effective in reducing Lp(a) concentrations by up to 30%. Statins have minimal or no effect on Lp(a). However, data for these and other promising Lp(a)-lowering therapies including mipomersen, lomitapide, cholesterol-ester-transfer protein inhibitors and eprotirome are derived from studies in the general, mainly high CVD risk, population, and include only subpopulations of postmenopausal women.

CONCLUSIONS

Past, present and emerging therapies can reduce Lp(a) concentrations to a varying extent. Overall, it remains to be proven whether the aforementioned reductions in Lp(a) by these therapeutic options are translated into CVD risk reduction in postmenopausal women.

Hypertriglyceridemia: the importance of identifying patients at risk

This review aims to explain risk factors, consequences, and management strategies recommended for patients with hypertriglyceridemia. A search of PubMed was performed: 'Hypertriglyceridemia'[Majr], limited to English-language and published in the 5 years up to April 2016. Abstracts of the 680 results were screened for inclusion. Reference lists of publications included were also screened for inclusion. Approximately 25% of the United States population has elevated (≥150 mg/dL) triglycerides (TG) putting them at an increased risk of cardiovascular disease, non-alcoholic fatty liver disease, and pancreatitis. Risk factors for hypertriglyceridemia include genetics, lifestyle and diet, renal disease, endocrine disorders, and certain medications. Guidelines recommend that all patients with hypertriglyceridemia are advised on lifestyle modification to reduce TG to <150 mg/dL; a reduction in body weight of 5-10% can reduce TG by approximately 20%. For patients with TG <400 mg/dL, the primary goal is to reduce low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol, with most guidelines recommending statin therapy. When TG is ≥500 mg/dL the primary goal is to reduce TG levels to lower the risk of pancreatitis. Statin therapy (if LDL-C is elevated) in combination with a fibrate, or long-chain omega-3 fatty acid may be required. The Food and Drug Administration withdrew approval for niacin and some fibrates in combination with statins in April 2016 citing unfavorable benefit-risk profiles. With the increasing incidence of associated conditions (e.g. obesity, metabolic syndrome, and type 2 diabetes mellitus), it is likely that primary care physicians will encounter more patients with hypertriglyceridemia.

HMG-CoA Reductase inhibitors: an updated review of patents of novel compounds and formulations (2011-2015)

INTRODUCTION

Statins are remarkably safe and efficient medications that are the mainstay of hypercholesterolemia treatment and have proven to be an invaluable tool to lower the risk of acute cardiovascular events. These compounds are inhibitors of 3-hydroxy-methylglutaryl CoA reductase (HMG-R), the rate-limiting enzyme in cholesterol biosynthesis. In spite of their success, they present undesirable side effects and are now loosing patent protection, which provides a great opportunity for the development of new and improved statins. Areas covered: This review summarizes the new patents for HMG-R inhibitors for the 2011-2015 period. Combinations of existing statins with other drugs are also addressed, as well as novel applications of existing statins. Expert opinion: Recent efforts for the discovery of HMG-CoA-R inhibitors has resulted in several new molecules. Most of these are based on commercially available statins, including sterol and terpenoid derivatives. A few peptides have also been patented. However, the origin of the side effects caused by previous statins continues to be, to a large extent, unknown. Although the patents published in the past 5 years are promising, and might result in new drugs, there is still no way to know if they will present reduced toxicity. Only future clinical trials will answer this question.

Lipid lowering activity of novel N-(benzoylphenyl)pyridine-3-carboxamide derivatives in Triton WR-1339-induced hyperlipidemic rats

CONTEXT

Dyslipidemia is a major risk factor for the development of cardiovascular diseases. Many dyslipidemic patients do not achieve their target lipid levels with the currently available medications, and most of them may experience many side effects.

OBJECTIVE

The present work aimed toward identifying a new class of novel nicotinic acid-carboxamide derivatives as promising antihyperlipidemic compounds.

MATERIALS AND METHODS

Six novel N-(benzoylphenyl)pyridine-3-carboxamide derivatives were synthesized using acid chloride pathways. All structures were confirmed using ¹H-NMR, ¹³C-NMR, IR, and HRMS. The evaluation of biological activity was conducted using Triton WR-1339-induced hyperlipidemic rats model.

RESULTS

This study revealed that some of the newly synthesized novel N-(benzoylphenyl)pyridine-3-carboxamide derivatives mainly C4 and C6 possessed significant antihyperlipidemic activities on lipid components TG and TC (p value <0.05).

DISCUSSION AND CONCLUSION

This research opens the door for new potential antihyperlipidemic compounds derived from nicotinic acid that need further optimization of their biological activities.

Triglyceride-rich lipoproteins as a causal factor for cardiovascular disease

Approximately 25% of US adults are estimated to have hypertriglyceridemia (triglyceride [TG] level ≥150 mg/dL [≥1.7 mmol/L]). Elevated TG levels are associated with increased cardiovascular disease (CVD) risk, and severe hypertriglyceridemia (TG levels ≥500 mg/dL [≥5.6 mmol/L]) is a well-established risk factor for acute pancreatitis. Plasma TG levels correspond to the sum of the TG content in TG-rich lipoproteins (TRLs; ie, very low-density lipoproteins plus chylomicrons) and their remnants. There remains some uncertainty regarding the direct causal role of TRLs in the progression of atherosclerosis and CVD, with cardiovascular outcome studies of TG-lowering agents, to date, having produced inconsistent results. Although low-density lipoprotein cholesterol (LDL-C) remains the primary treatment target to reduce CVD risk, a number of large-scale epidemiological studies have shown that elevated TG levels are independently associated with increased incidence of cardiovascular events, even in patients treated effectively with statins. Genetic studies have further clarified the causal association between TRLs and CVD. Variants in several key genes involved in TRL metabolism are strongly associated with CVD risk, with the strength of a variant's effect on TG levels correlating with the magnitude of the variant's effect on CVD. TRLs are thought to contribute to the progression of atherosclerosis and CVD via a number of direct and indirect mechanisms. They directly contribute to intimal cholesterol deposition and are also involved in the activation and enhancement of several proinflammatory, proapoptotic, and procoagulant pathways. Evidence suggests that non-high-density lipoprotein cholesterol, the sum of the total cholesterol carried by atherogenic lipoproteins (including LDL, TRL, and TRL remnants), provides a better indication of CVD risk than LDL-C, particularly in patients with hypertriglyceridemia. This article aims to provide an overview of the available epidemiological, clinical, and genetic evidence relating to the atherogenicity of TRLs and their role in the progression of CVD.

Nicotinic acid supplementation in diet favored intramuscular fat deposition and lipid metabolism in finishing steers

Nicotinic acid (NA) acting as the precursor of NAD(+)/NADH and NADP(+)/NADPH, participates in many biochemical processes, e.g. lipid metabolism. The main purpose of this study was to investigate the effects of dietary NA on carcass traits, meat quality, blood metabolites, and fat deposition in Chinese crossbred finishing steers. Sixteen steers with the similar body weight and at the age of 24 months were randomly allocated into control group (feeding basal diet) and NA group (feeding basal diet + 1000 mg/kg NA). All experimental cattle were fed a 90% concentrate diet and 10% forage straw in a 120-day feeding experiment. The results showed that supplemental NA in diet increased longissimus area, intramuscular fat content (17.14% vs. 9.03%), marbling score (8.08 vs. 4.30), redness (a*), and chroma (C*) values of LD muscle, but reduced carcass fat content (not including imtramuscular fat), pH24 h and moisture content of LD muscle, along with no effect on backfat thickness. Besides, NA supplementation increased serum HDL-C concentration, but decreased the serum levels of LDL-C, triglyceride, non-esterified fatty acid, total cholesterol, and glycated serum protein. In addition, NA supplementation increased G6PDH and ICDH activities of LD muscle. These results suggested that NA supplementation in diet improves the carcass characteristics and beef quality, and regulates the compositions of serum metabolites. Based on the above results, NA should be used as the feed additive in cattle industry.

Regression of Atherosclerosis: The Journey From the Liver to the Plaque and Back

Cardinal events in atherogenesis are the retention of apolipoprotein B-containing lipoproteins in the arterial wall and the reaction of macrophages to these particles. My laboratory has been interested in both the cell biological events producing apolipoprotein B-containing lipoproteins, as well as in the reversal of the damage they cause in the plaques formed in the arterial wall. In the 2013 George Lyman Duff Memorial Lecture, as summarized in this review, I covered 3 areas of my past, present, and future interests, namely, the regulation of hepatic very low density lipoprotein production by the degradation of apolipoprotein B100, the dynamic changes in macrophages in the regression of atherosclerosis, and the application of nanoparticles to both image and treat atherosclerotic plaques.

Niacin Suppresses Progression of Atherosclerosis by Inhibiting Vascular Inflammation and Apoptosis of Vascular Smooth Muscle Cells

Background

Niacin is a broad-spectrum lipid-regulating drug used for the clinical therapy of atherosclerosis; however, the mechanisms by which niacin ameliorates atherosclerosis are not clear.

Material/Methods

The effect of niacin on atherosclerosis was assessed by detection of atherosclerotic lesion area. Adhesion molecules in arterial endothelial cells were determined by using qRT-PCR and Western blot analysis. The levels of serum inflammatory cytokines in ApoE^−/− mice were detected by using ELISA. We detected the expression levels of phosphorylated nuclear factors-κB (NF-κB) p65 in aortic endothelial cells of mice using Western blot analysis. Furthermore, we investigated the anti-inflammation effect and endothelium-protecting function of niacin and their regulatory mechanisms in vitro.

Results

Niacin inhibited the progress of atherosclerosis and decreased the levels of serum inflammatory cytokines and adhesion molecules in ApoE^−/− mice. Niacin suppressed the activity of NF-κB and apoptosis of vascular smooth muscle cells (VSMCs). Furthermore, niacin induced phosphorylated focal adhesion kinase (FAK) and FAK inhibitor PF-573228 reduced the level of Bcl-2 and elevated the level of cleaved caspase-3 in VSMCs.

Conclusions

Niacin inhibits vascular inflammation and apoptosis of VSMCs via inhibiting the NF-κB signaling and the FAK signaling pathway, respectively, thus protecting ApoE^−/− mice against atherosclerosis.

Current therapies for lowering lipoprotein (a)

Lipoprotein (a) [Lp(a)] is a human plasma lipoprotein with unique structural and functional characteristics. Lp(a) is an assembly of two components: a central core with apoB and an additional glycoprotein, called apo(a). Ever since the strong association between elevated levels of Lp(a) and an increased risk for CVD was recognized, interest in the therapeutic modulation of Lp(a) levels has increased. Here, the past and present therapies aiming to lower Lp(a) levels will be reviewed, demonstrating that these agents have had varying degrees of success. The next challenge will be to prove that Lp(a) lowering also leads to cardiovascular benefit in patients with elevated Lp(a) levels. Therefore, highly specific and potent Lp(a)-lowering strategies are awaited urgently.

[Consecutive formation of the functions of high-, low-density and very-low-density lipoproteins during phylogenesis. Unique algorithm of the effects of lipid-lowering drugs]

During phylogenesis, all fatty acids (FA) were initially transported to cells by apoA-I high-density lipoproteins (HDL) in polar lipids. Later, active cellular uptake of saturated, monoenoic and unsaturated FA occurred via triglycerides (TG) in low-density lipoproteins (LDL). Active uptake of polyenoic FA (PUFA) required the following: a) PUFA re-esterified from polar phospholipids into nonpolar cholesteryl polyesters (poly-CLE), b) a novel protein, cholesteryl ester transfer protein (CETP), initiated poly-CLE transformation from HDL to LDL. CETP formed blood HDL-CETP-LDL complexes in which poly-CLE spontaneously came from polar lipids of TG in HDL to nonpolar TG in LDL. Then ligand LDLs formed and the cells actively absorbed PUFA via apoB-100 endocytosis. Some animal species (rats, mice, dogs) developed a spontaneous CETP-minus mutation followed by population death from atherosclerosis. However, there was another active CETP-independent uptake formed during phylogenesis; the cells internalized poly-CLE in HDL. Since apoA-I had no domain-ligand, another apoE/A-I ligand formed; the cells began synthesizing apoE/A-1 receptors. In cells of rabbits and primates absorbed cells PUFA consecutively: HDL-->LDL-->apoB-100 endocytosis; those of rats and dogs did HDL directly: HDL-->anoE/A-I endocytosis. In the rabbits, CETP was high, apoE in HDL was low, and the animals were sensitive to exogenous hypercholesterolemia. In the rats, CETP was low and ApoE in HDL-was high, and the animals were resistant to hypercholesterolemia. Reduced bioavailability of PUFA during their consecutive cellular uptake and develdpment of intercellular PUFA deficiency are fundamental to the pathogenesis of atherosclerosis.

Redox Roles of Reactive Oxygen Species in Cardiovascular Diseases

Cardiovascular disease (CVD), a major cause of mortality in the world, has been extensively studied over the past decade. However, the exact mechanism underlying its pathogenesis has not been fully elucidated. Reactive oxygen species (ROS) play a pivotal role in the progression of CVD. Particularly, ROS are commonly engaged in developing typical characteristics of atherosclerosis, one of the dominant CVDs. This review will discuss the involvement of ROS in atherosclerosis, specifically their effect on inflammation, disturbed blood flow and arterial wall remodeling. Pharmacological interventions target ROS in order to alleviate oxidative stress and CVD symptoms, yet results are varied due to the paradoxical role of ROS in CVD. Lack of effectiveness in clinical trials suggests that understanding the exact role of ROS in the pathophysiology of CVD and developing novel treatments, such as antioxidant gene therapy and nanotechnology-related antioxidant delivery, could provide a therapeutic advance in treating CVDs. While genetic therapies focusing on specific antioxidant expression seem promising in CVD treatments, multiple technological challenges exist precluding its immediate clinical applications.

Nonstatin therapies for management of dyslipidemia: a review

PURPOSE

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the United States. Recently published cholesterol treatment guidelines emphasize the use of statins as the preferred treatment strategy for both primary and secondary prevention of CVD. However, the optimal treatment strategy for patients who cannot tolerate statin therapy or those who need additional lipid-lowering therapy is unclear in light of recent evidence that demonstrates a lack of improved cardiovascular outcomes with combination therapy. The purpose of this review is to summarize and interpret evidence that evaluates nonstatin drug classes in reducing cardiovascular outcomes, to provide recommendations for use of nonstatin therapies in clinical practice, and to review emerging nonstatin therapies for management of dyslipidemia.

METHODS

Relevant articles were identified through searches of PubMed, International Pharmaceutical Abstracts, and the Cochrane Database of Systematic Reviews by using the terms niacin, omega-3 fatty acids (FAs), clofibrate, fibrate, fenofibrate, fenofibric acid, gemfibrozil, cholestyramine, colestipol, colesevelam, ezetimibe, proprotein convertase subtilisin/kexin 9 (PCSK9), cholesteryl ester transfer protein (CETP), and cardiovascular outcomes. Only English language, human clinical trials, meta-analyses, and systematic reviews were included. Additional references were identified from citations of published articles.

FINDINGS

Niacin may reduce cardiovascular events as monotherapy; however, recent trials in combination with statins have failed to show a benefit. Trials with omega-3 FAs have failed to demonstrate significant reductions in cardiovascular outcomes. Fibrates may improve cardiovascular outcomes as monotherapy; however, trials in combination with statins have failed to show a benefit, except in those with elevated triglycerides (>200 mg/dL) or low HDL-C (<40 mg/dL). There is a lack of data that evaluates bile acid sequestrant in combination with statin therapy on reducing cardiovascular events. Ezetimibe-statin combination therapy can reduce cardiovascular outcomes in those with chronic kidney disease and following vascular surgery or acute coronary syndrome. Long-term effects of emerging nonstatin therapies (CETP and PCSK9 inhibitors) are currently being evaluated in ongoing Phase III trials.

IMPLICATIONS

Nonstatin therapies have a limited role in reducing cardiovascular events in those maintained on guideline-directed statin therapy. In certain clinical situations, such as patients who are unable to tolerate statin therapy or recommended intensities of statin therapy, those with persistent severe elevations in triglycerides, or patients with high cardiovascular risk, some nonstatin therapies may be useful in reducing cardiovascular events. Future research is needed to evaluate the role of nonstatin therapies in those who are unable to tolerate guideline-directed statin doses.

Effects of Extended-Release Nicotinic Acid on Apolipoprotein (a) Kinetics in Hypertriglyceridemic Patients

OBJECTIVE

To determine the mechanisms by which extended-release nicotinic acid reduces circulating lipoprotein (a) concentrations in hypertriglyceridemic patients.

APPROACH AND RESULTS

Eight nondiabetic, obese male subjects (aged 48±12 years; body mass index, 31.2±1.8 kg/m(2)) with hypertriglyceridemia (triglycerides, 226±78 mg/dL) were enrolled in an 8 week, double blind, placebo-controlled cross-over study. At the end of each treatment phase, fasted subjects received a 10 µmol/L per kg bolus injection of [5,5,5-(2)H3]-l-Leucine immediately followed by constant infusion of [5,5,5-(2)H3]-l-Leucine (10 µmol L(-1) kg(-1) h(-1)) for 14 hours, and blood samples were collected. A liquid chromatography-tandem mass spectrometry method was used to study apolipoprotein (a) (Apo(a)) kinetics. The fractional catabolic rate of Apo(a) was calculated with a single compartmental model using the apolipoprotein B100 (ApoB100) containing very low density lipoprotein tracer enrichment as a precursor pool. Extended-release nicotinic acid decreased plasma triglycerides (-46%; P=0.023), raised high-density lipoprotein cholesterol (+20%; P=0.008), and decreased Apo(a) plasma concentrations (-20%; P=0.008). Extended-release nicotinic acid also decreased ApoB100 (22%; P=0.008) and proprotein convertase subtilisin/kexin type 9 (PCSK9, -29%; P=0.008) plasma concentrations. Apo(a) fractional catabolic rate and production rates were decreased by 37% (0.58±0.28 versus 0.36±0.19 pool/d; P=0.008) and 50% (1.4±0.8 versus 0.7±0.4 nmol/kg per day; P=0.008), respectively.

CONCLUSIONS

Extended-release nicotinic acid treatment decreased Apo(a) plasma concentrations by 20%, production rates by 50%, and catabolism by 37%. ApoB100 and PCSK9 concentrations were also decreased by treatment, but no correlation was found with Apo(a) kinetic parameters.

Evolving targets for lipid-modifying therapy

The pathogenesis and progression of atherosclerosis are integrally connected to the concentration and function of lipoproteins in various classes. This review examines existing and emerging approaches to modify low-density lipoprotein and lipoprotein (a), triglyceride-rich lipoproteins, and high-density lipoproteins, emphasizing approaches that have progressed to clinical evaluation. Targeting of nuclear receptors and phospholipases is also discussed.

Chylomicronaemia--current diagnosis and future therapies

This Review discusses new developments in understanding the basis of chylomicronaemia--a challenging metabolic disorder for which there is an unmet clinical need. Chylomicronaemia presents in two distinct primary forms. The first form is very rare monogenic early-onset chylomicronaemia, which presents in childhood or adolescence and is often caused by homozygous mutations in the gene encoding lipoprotein lipase (LPL), its cofactors apolipoprotein C-II or apolipoprotein A-V, the LPL chaperone lipase maturation factor 1 or glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1. The second form, polygenic late-onset chylomicronaemia, which is caused by an accumulation of several genetic variants, can be exacerbated by secondary factors, such as poor diet, obesity, alcohol intake and uncontrolled type 1 or type 2 diabetes mellitus, and is more common than early-onset chylomicronaemia. Both forms of chylomicronaemia are associated with an increased risk of life-threatening pancreatitis; the polygenic form might also be associated with an increased risk of cardiovascular disease. Treatment of chylomicronaemia focuses on restriction of dietary fat and control of secondary factors, as available pharmacological therapies are only minimally effective. Emerging therapies that might prove more effective than existing agents include LPL gene therapy, inhibition of microsomal triglyceride transfer protein and diacylglycerol O-acyltransferase 1, and interference with the production and secretion of apoC-III and angiopoietin-like protein 3.

Effects of formulation design on niacin therapeutics: mechanism of action, metabolism, and drug delivery

Niacin is a highly effective, lipid regulating drug associated with a number of metabolically induced side effects such as prostaglandin (PG) mediated flushing and hepatic toxicity. In an attempt to reduce the development of these adverse effects, scientists have investigated differing methods of niacin delivery designed to control drug release and alter metabolism. However, despite successful formulation of various orally based capsule and tablet delivery systems, patient adherence to niacin therapy is still compromised by adverse events such as PG-induced flushing. While the primary advantage of orally dosed formulations is ease of use, alternative delivery options such as transdermal delivery or polymeric micro/nanoparticle encapsulation for oral administration have shown promise in niacin reformulation. However, the effectiveness of these alternative delivery options in reducing inimical effects of niacin and maintaining drug efficacy is still largely unknown and requires more in-depth investigation. In this paper, we present an overview of niacin applications, its metabolic pathways, and current drug delivery formulations. Focus is placed on oral immediate, sustained, and extended release niacin delivery as well as combined statin and/or prostaglandin antagonist niacin formulation. We also examine and discuss current findings involving transdermal niacin formulations and polymeric micro/nanoparticle encapsulated niacin delivery.

Effect of Extended-Release Niacin/Laropiprant Combination on Plasma Adiponectin and Insulin Resistance in Chinese Patients with Dyslipidaemia

Objectives. This study examined whether the increase of adiponectin associated with extended-release (ER) niacin/laropiprant combination attenuates the adverse effect of niacin on glucose and insulin resistance in Hong Kong Chinese patients with dyslipidaemia. Methods. Patients (N = 121) were treated with ER niacin/laropiprant 1 g/20 mg for 4 weeks and then the dose was doubled for an additional 8 weeks. Measurements of fasting lipids, glucose, insulin, and adiponectin were performed at baseline and during the study. Results. There were significant (P < 0.001) increases in glucose (9.4 ± 13.1%), insulin (70.2 ± 91.0%), HOMA-IR (87.8 ± 103.9%), and adiponectin (169.3 ± 111.6%). The increase in adiponectin was significantly associated with increase in glucose (r = 0.221, P < 0.05), insulin (r = 0.184, P < 0.05), and HOMA-IR (r = 0.237, P < 0.01) and the association remained significant after adjustment for changes in body weight or body fat mass. Conclusion. Treatment with ER niacin/laropiprant led to a significant increase in adiponectin levels but worsening of glucose levels and insulin resistance, and the increase in adiponectin and insulin resistance were correlated suggesting the increase in adiponectin did not ameliorate the deterioration in insulin resistance. Clinical trial is registered with number on WHO-ICTRP: ChiCTR-ONC-10001038.

Niacin as antidyslipidemic drug

Niacin is an important vitamin (B3) that can be used in gram doses to positively modify pathogenetically relevant lipid disorders: elevated LDL cholesterol, elevated non-HDL cholesterol, elevated triglycerides, elevated lipoprotein(a), and reduced HDL cholesterol. This review reports the latest published findings with respect to niacin's mechanisms of action on these lipids and its anti-inflammatory and anti-atherosclerotic effects. In the pre-statin era, niacin was shown to have beneficial effects on cardiovascular end-points; but in recent years, two major studies performed in patients whose LDL cholesterol levels had been optimized by a statin therapy did not demonstrate an additional significant effect on these end-points in the groups where niacin was administered. Both studies have several drawbacks that suggest that they are not representative for other patients. Thus, niacin still plays a role either as an additive to a statin or as a substitute for a statin in statin-intolerant patients. Moreover, patients with elevated triglyceride and low HDL cholesterol levels and patients with elevated lipoprotein(a) concentrations will possibly benefit from niacin, although currently the study evidence for these indications is rather poor. Niacin may be useful for compliant patients, however possible side effects (flushing, liver damage) and contraindications should be taken into consideration.

HDL re-examined

PURPOSE OF REVIEW

To summarize the current evidence concerning the role of HDL-C and HDL-associated parameters in the risk for cardiovascular disease (CVD).

RECENT FINDINGS

Numerous population studies have shown that plasma levels of HDL-C are inversely associated with CVD risk; in patient care HDL-C levels are therefore widely implemented in risk estimation models. A number of antiatherogenic properties have been ascribed to the HDL particle, but the hypothesis that HDL is causally related to CVD has been seriously challenged by recent data obtained from both human genetic studies and clinical trials. The final word on HDL-C as a therapeutic target is pending, as a number of clinical endpoint trials specifically focusing on the effect(s) of HDL-C increasing agents are underway. Moreover, recent data show that HDL efflux capacity could hold independent predictive value for CVD events, which clearly highlights the potential need to focus on HDL functionality, rather than on HDL-C levels.

SUMMARY

The dogmatic concept that HDL-C levels predict future CVD events is undisputed, but the role of HDL-C as a causal factor in atherosclerosis has been challenged by a number of different types of studies. In recent years, a paradigm shift toward 'HDL functionality' is apparent. Whether or not optimizing these markers of HDL functionality actually does reduce CVD risk requires formal testing in prospective controlled studies.