High density lipoprotein in atherosclerosis and coronary heart disease: Where do we stand today?

Effect of Hormone Therapy on Lipoprotein Subfractions in Early and Late Postmenopausal Women

CONTEXT

The Early vs Late Intervention Trial with Estradiol (ELITE) showed that hormone therapy (HT) reduced atherosclerosis progression among early but not late postmenopausal women (PMW).

OBJECTIVE

Determined by time-since-menopause (1) HT effects on lipids and lipoprotein particle subfractions (LPs), (2) associations of estradiol (E2) level with lipids and LPs, (3) associations of lipids and LPs with atherosclerosis progression.

DESIGN

Randomized controlled trial stratified by time-since-menopause.

SETTING

Academic institution.

PARTICIPANTS

Healthy postmenopausal women.

INTERVENTION

Oral E2 with/without sequential vaginal progesterone.

MAIN OUTCOME MEASURES

Standard lipids and 21 LPs quantitated by ion mobility every 6 months.

RESULTS

Among 562 PMW (240 early, 322 late), HT significantly increased total triglycerides (TG), high-density lipoprotein (HDL) cholesterol, small low-density lipoproteins (LDL), large HDL, and TG/C ratio in LDL and HDL and decreased LDL-cholesterol, total very low density lipoproteins (VLDL), small VLDL, intermediate-density lipoproteins, large LDL, and LDL peak diameter. HT showed no lipid or LP differences between time-since-menopause. Associations of E2 level with lipids and LPs explained the HT effects. Despite the nonsignificant P interaction by time-since-menopause, we observed that very small LDL and total HDL LPs were associated with atherosclerosis progression in late PMW.

CONCLUSION

HT effects on standard lipids and LPs are consistent with the literature. HT has similar effect on lipids and LPs in early and late PMW. Novel findings include discordant effects of HT on TG and VLDL particles, which can be explained by increased catabolism of atherogenic remnants of TG-rich lipoproteins. Our findings extend the well-known HT effects on standard lipids and LPs that may contribute to the beneficial effects on atherosclerosis progression in PMW.

Effect of a Novel Lavender Extract on Plasma Lipid and Lipoprotein Metabolism, Glucose Tolerance and Adipose Tissue Metabolic Activation: A Preclinical Safety and Efficacy Study

BACKGROUND/OBJECTIVES

Lavender has been utilized for its medicinal properties since ancient times, with numerous health benefits reported. This study aimed to valorize solid waste from lavender essential oil production by developing a novel lavender extract from solid lavender residues. The extract's preclinical safety and efficacy were evaluated with emphasis on plasma lipid and lipoprotein metabolism, glucose tolerance, and adipose tissue metabolic activity.

METHODS

Male C57BL/6 mice were divided into four groups of five mice each and fed for 30 days with lavender extract encapsulated in 10% maltodextrin, mixed with a standard chow diet. The first group (Lav 1×) received 21.1 mg/kg/day, the second group (Lav 10×) received 211 mg/kg/day, and the third group (Lav 100×) received 2110 mg/kg/day. A placebo group consumed the standard diet without lavender extract. Key outcomes included plasma lipid and lipoprotein profiles, transaminase levels, HDL antioxidant and anti-inflammatory potential, glucose tolerance, and mitochondrial activity in white (WAT) and brown (BAT) adipose tissues.

RESULTS

The novel lavender extract induced dose-dependent improvements in lipid and lipoprotein metabolism, glucose tolerance, and adipose tissue activity. The 2110 mg/kg dose (100×) demonstrated the most significant beneficial effects, although it was associated with a slight elevation in hepatic transaminase levels, indicating potential mild hepatic stress. Conclusions: Overall, the novel lavender extract exhibits promising health benefits with no major safety concerns at the tested doses, supporting its potential for therapeutic applications.

Association of objectively measured walking speed with incident cardiovascular diseases in middle-aged and older Chinese adults

OBJECTIVE

To evaluate the association between objectively measured walking speed and cardiovascular disease (CVD) risk in middle-aged and elderly Chinese adults.

METHODS

A total of 3969 participants from the China Health and Retirement Longitudinal Study (CHARLS) were included in this study. Multilevel logistic and linear regression models (community-household-individual) were used to estimate the association between walking speed and the risk of CVD.

RESULTS

A total of 1037 participants had a CVD event during the follow-up period, including 776 (19.6%) cases of cardiac disease and 353 (8.9%) cases of stroke. Participants who walked faster had a lower risk of CVD (tertile 2: OR = 0.80, 95% CI: 0.67-0.97, P = 0.022; tertile 3: OR = 0.73, 95% CI: 0.60-0.89, P = 0.002). Further analysis showed that participants who walked faster also had a lower risk of cardiac disease and stroke (cardiac disease: tertile 2: OR = 0.91, 95% CI: 0.74-1.12, P = 0.368; tertile 3: OR = 0.85, 95% CI: 0.68-1.07, P = 0.161; stroke: tertile 2: OR = 0.33, 95% CI: 0.14-0.78, P = 0.012; tertile 3: OR = 0.30, 95% CI: 0.11-0.82, P = 0.019). The results were consistent in pre-specified subgroups by sex, age, and body mass index.

CONCLUSION

We found that faster, objectively measured walking speed was significantly associated with a lower risk of CVD, especially stroke, in middle-aged and elderly Chinese people.

Impact of Vitamin E Supplementation on High-Density Lipoprotein in Patients With Haptoglobin Genotype-Stratified Diabetes: A Systematic Review of Randomized Controlled Trials

Background: Vitamin E, an essential micronutrient with antioxidant potential, can dramatically reduce the cardiovascular risk in individuals with haptoglobin (Hp) 2-2 genotype diabetes; however, the underlying mechanism remains unclear. Objective: The objective of this study is to evaluate the effect of vitamin E supplementation on high-density lipoprotein (HDL) levels and function in individuals with diabetes stratified by Hp genotype. Methods: All relevant studies published up to May 2023 were systematically reviewed using PubMed, Cochrane Library, Web of Science, Chinese Wanfang, China Science and Technology Journal, and Chinese National Knowledge Infrastructure databases. Randomized controlled trials that evaluated the effects of vitamin E supplementation on HDL levels were included. The outcomes assessed were changes in HDL concentrations, cholesterol efflux, and HDL-associated lipid peroxides. Results: In total, 163 publications were selected. Based on inclusion and exclusion selection and quality assessment, five studies with 463 participants were included. Vitamin E supplementation did not exert any effect on HDL levels in individuals with diabetes with any Hp genotype. Three of the five studies revealed that vitamin E improved cholesterol efflux and HDL lipid peroxides in individuals with Hp2-2 diabetes but did not positively impact HDL function in Hp1 carriers. Conclusions: Although vitamin E supplementation did not significantly impact HDL levels in individuals with diabetes of any Hp genotype, it may improve HDL function in individuals with Hp2-2 diabetes. These findings indicate a pharmacogenetic interaction between vitamin E and the Hp genotype on HDL function. Moreover, vitamin E supplementation may be an effective strategy for specific individuals with diabetes.

Cholesterol transport and beyond: Illuminating the versatile functions of HDL apolipoproteins through structural insights and functional implications

High-density lipoproteins (HDLs) play a vital role in lipid metabolism and cardiovascular health, as they are intricately involved in cholesterol transport and inflammation modulation. The proteome of HDL particles is indeed complex and distinct from other components in the bloodstream. Proteomics studies have identified nearly 285 different proteins associated with HDL; however, this review focuses more on the 15 or so traditionally named "apo" lipoproteins. Important lipid metabolizing enzymes closely working with the apolipoproteins are also discussed. Apolipoproteins stand out for their integral role in HDL stability, structure, function, and metabolism. The unique structure and functions of each apolipoprotein influence important processes such as inflammation regulation and lipid metabolism. These interactions also shape the stability and performance of HDL particles. HDLs apolipoproteins have multifaceted roles beyond cardiovascular diseases (CVDs) and are involved in various physiological processes and disease states. Therefore, a detailed exploration of these apolipoproteins can offer valuable insights into potential diagnostic markers and therapeutic targets. This comprehensive review article aims to provide an in-depth understanding of HDL apolipoproteins, highlighting their distinct structures, functions, and contributions to various physiological processes. Exploiting this knowledge holds great potential for improving HDL function, enhancing cholesterol efflux, and modulating inflammatory processes, ultimately benefiting individuals by limiting the risks associated with CVDs and other inflammation-based pathologies. Understanding the nature of all 15 apolipoproteins expands our knowledge of HDL metabolism, sheds light on their pathological implications, and paves the way for advancements in the diagnosis, prevention, and treatment of lipid and inflammatory-related disorders.

Biomembrane-Modified Biomimetic Nanodrug Delivery Systems: Frontier Platforms for Cardiovascular Disease Treatment

Cardiovascular diseases (CVDs) are one of the leading causes of death worldwide. Despite significant advances in current drug therapies, issues such as poor drug targeting and severe side effects persist. In recent years, nanomedicine has been extensively applied in the research and treatment of CVDs. Among these, biomembrane-modified biomimetic nanodrug delivery systems (BNDSs) have emerged as a research focus due to their unique biocompatibility and efficient drug delivery capabilities. By modifying with biological membranes, BNDSs can effectively reduce recognition and clearance by the immune system, enhance biocompatibility and circulation time in vivo, and improve drug targeting. This review first provides an overview of the classification and pathological mechanisms of CVDs, then systematically summarizes the research progress of BNDSs in the treatment of CVDs, discussing their design principles, functional characteristics, and clinical application potential. Finally, it highlights the issues and challenges faced in the clinical translation of BNDSs.

High-density lipoprotein in diabetes: Structural and functional relevance

Low levels of high-density lipoprotein-cholesterol (HDL-C) is considered a major cardiovascular risk factor. However, recent studies have suggested a more U-shaped association between HDL-C and cardiovascular disease. It has been shown that the cardioprotective effect of HDL is related to the functions of HDL particles rather than their cholesterol content. HDL particles are highly heterogeneous and have multiple functions relevant to cardiometabolic conditions including cholesterol efflux capacity, anti-oxidative, anti-inflammatory, and vasoactive properties. There are quantitative and qualitative changes in HDL as well as functional abnormalities in both type 1 and type 2 diabetes. Non-enzymatic glycation, carbamylation, oxidative stress, and systemic inflammation can modify the HDL composition and therefore the functions, especially in situations of poor glycemic control. Studies of HDL proteomics and lipidomics have provided further insights into the structure-function relationship of HDL in diabetes. Interestingly, HDL also has a pleiotropic anti-diabetic effect, improving glycemic control through improvement in insulin sensitivity and β-cell function. Given the important role of HDL in cardiometabolic health, HDL-based therapeutics are being developed to enhance HDL functions rather than to increase HDL-C levels. Among these, recombinant HDL and small synthetic apolipoprotein A-I mimetic peptides may hold promise for preventing and treating diabetes and cardiovascular disease.

The association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and prevalence of periodontitis among US adults: a cross-sectional NHANES study

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) is a recently developed lipid parameter, but there is currently a lack of research exploring its relationship with periodontitis. This study aims to identify the potential association between NHHR and periodontitis. The association between NHHR and periodontitis were examined through univariate and multivariate weighted logistic regression utilizing the National Health and Nutrition Examination Survey data from 2009 to 2014. The participants were grouped based on the type of periodontitis. This study included a total of 9023 participants, with 1947 individuals having no periodontitis, and an additional 7076 individuals suffering from periodontitis. Patients in periodontitis group demonstrated a statistically significant elevation in NHHR values 2.82 (2.05-3.80) compared to those in no periodontitis group (p < 0.001). Logistic regression analysis of variables demonstrated a positive association between NHHR and periodontitis [1.07 (1.02, 1.12) p = 0.0067]. The study revealed a positive association between NHHR and an elevated prevalence of periodontitis development. For each unit increase in NHHR, there is a 7% increase in the prevalence of periodontitis. Further investigations into NHHR may enhance our understanding of preventing and treating periodontitis. However, additional studies are required to validate these findings.

Multivessel Coronary Artery Disease Complicated by Diabetes Mellitus Has a Relatively Small Effect on Endothelial and Lipoprotein Lipases Expression in the Human Atrial Myocardium and Coronary Perivascular Adipose Tissue

Endothelial (EL) and lipoprotein (LPL) lipases are enzymes involved in lipoproteins metabolism and formation of atherosclerosis, a pathological feature of coronary artery disease (CAD). This paper examines the role of the lipases in the right atrial appendage (RAA) and coronary perivascular adipose tissue (PVAT) of patients with CAD alone or with accompanying diabetes. Additionally, correlation analysis for plasma concentration of the lipases, apolipoproteins (ApoA-ApoJ) and blood lipids (Chol, HDL-C, LDL-C, TAG) was performed. We observed that CAD had little effect on the lipases gene/protein levels in the RAA, while their transcript content was elevated in the PVAT of diabetic CAD patients. Interestingly, the RAA was characterized by higher expression of EL/LPL (EL: +1-fold for mRNA, +5-fold for protein; LPL: +2.8-fold for mRNA, +12-fold for protein) compared to PVAT. Furthermore, ApoA1 plasma concentration was decreased, whereas ApoC1 and ApoH were increased in the patients with CAD and/or diabetes. The concentrations of ApoC3 and ApoD were strongly positively correlated with TAG content in the blood, and the same was true for ApoB with respect to LDL-C and total cholesterol. Although plasma concentrations of EL/LPL were elevated in the patients with diabetes, CAD alone had little effect on blood, myocardial and perivascular fat expression of the lipases.

High-Density Lipoprotein in Metabolic Disorders and Beyond: An Exciting New World Full of Challenges and Opportunities

High-density lipoprotein (HDL) is an enigmatic member of the plasma lipid and lipoprotein transport system, best known for its ability to promote the reverse cholesterol efflux and the unloading of excess cholesterol from peripheral tissues. More recently, data in experimental mice and humans suggest that HDL may play important novel roles in other physiological processes associated with various metabolic disorders. Important parameters in the HDL functions are its apolipoprotein and lipid content, further reinforcing the principle that HDL structure defines its functionality. Thus, based on current evidence, low levels of HDL-cholesterol (HDL-C) or dysfunctional HDL particles contribute to the development of metabolic diseases such as morbid obesity, type 2 diabetes mellitus, and nonalcoholic fatty liver disease. Interestingly, low levels of HDL-C and dysfunctional HDL particles are observed in patients with multiple myeloma and other types of cancer. Therefore, adjusting HDL-C levels within the optimal range and improving HDL particle functionality is expected to benefit such pathological conditions. The failure of previous clinical trials testing various HDL-C-raising pharmaceuticals does not preclude a significant role for HDL in the treatment of atherosclerosis and related metabolic disorders. Those trials were designed on the principle of "the more the better", ignoring the U-shape relationship between HDL-C levels and morbidity and mortality. Thus, many of these pharmaceuticals should be retested in appropriately designed clinical trials. Novel gene-editing-based pharmaceuticals aiming at altering the apolipoprotein composition of HDL are expected to revolutionize the treatment strategies, improving the functionality of dysfunctional HDL.

LDL-cholesterol control in the primary prevention of cardiovascular diseases: An expert opinion for clinicians and health professionals

AIMS

Although adequate clinical management of patients with hypercholesterolemia without a history of known cardiovascular disease is essential for prevention, these subjects are often disregarded. Furthermore, the scientific literature on primary cardiovascular prevention is not as rich as that on secondary prevention; finally, physicians often lack adequate tools for the effective management of subjects in primary prevention and have to face some unsolved relevant issues. This document aims to discuss and review the evidence available on this topic and provide practical guidance.

DATA SYNTHESIS

Available algorithms and risk charts represent the main tool for the assessment of cardiovascular risk in patients in primary prevention. The accuracy of such an estimate can be substantially improved considering the potential contribution of some additional risk factors (C-reactive protein, lipoprotein(a), family history of cardiovascular disease) and conditions (environmental pollution, sleep quality, socioeconomic status, educational level) whose impact on the cardiovascular risk has been better understood in recent years. The availability of non-invasive procedures to evaluate subclinical atherosclerosis may help to identify subjects needing an earlier intervention. Unveiling the presence of these conditions will improve cardiovascular risk estimation, granting a more appropriate intervention.

CONCLUSIONS

The accurate assessment of cardiovascular risk in subjects in primary prevention with the use of algorithms and risk charts together with the evaluation of additional factors will allow physicians to approach each patient with personalized strategies, which should translate into an increased adherence to therapy and, as a consequence, a reduced cardiovascular risk.

Predictive value of HDL function in patients with coronary artery disease: relationship with coronary plaque characteristics and clinical events

BACKGROUND

HDL is endowed with several metabolic, vascular, and immunoinflammatory protective functions. Among them, a key property is to promote reverse cholesterol transport from cells back to the liver. The aim of this study was to estimate the association of scavenger receptor class B type I (SR-BI)- and ATP binding cassette transporter A1 (ABCA1)-mediated cholesterol efflux (the two major routes for cholesterol efflux to HDL) with the presence, extent, and severity of coronary artery disease (CAD), vascular wall remodelling processes, coronary plaque characteristics, and the incidence of myocardial infarction in the different subgroups of patients from the CAPIRE study.

METHODS

Patients (n = 525) from the CAPIRE study were divided into two groups: low-risk factors (RF), with 0-1 RF (n = 263), and multiple-RF, with ≥2 RFs; within each group, subjects were classified as no-CAD or CAD based on the segment involvement score (SIS) evaluated by coronary computed tomography angiography (SIS = 0 and SIS > 5, respectively). SR-BI- and ABCA1-mediated cholesterol efflux were measured using the plasma of all patients.

RESULTS

SR-BI-mediated cholesterol efflux was significantly reduced in patients with CAD in both the low-RF and multiple-RF groups, whereas ABCA1-mediated cholesterol efflux was similar among all groups. In CAD patients, multivariable analysis showed that SR-BI-mediated cholesterol efflux <25^th percentile predicted cardiovascular outcome (odds ratio 4.1; 95% CI: 1.3-13.7; p = .019), whereas ABCA-1-mediated cholesterol efflux and HDL-C levels significantly did not. Despite this finding, reduced SR-BI-mediated cholesterol efflux was not associated with changes in high-risk plaque features or changes in the prevalence of elevated total, non-calcified, and low-attenuation plaque volume.

CONCLUSION

SR-BI-mediated cholesterol efflux capacity is lower in patients with diffuse coronary atherosclerosis. In addition, a lower SR-BI-mediated cholesterol efflux capacity is associated with the worst clinical outcomes in patients with CAD, independently of atherosclerotic plaque features. Key MessagesIncreased cholesterol efflux capacity, an estimate of HDL function, is associated with a reduced CVD risk, regardless of HDL-C levels.HDL-C levels are significantly lower in patients with CAD.Lower SR-BI-mediated cholesterol efflux capacity is observed in patients with diffuse coronary atherosclerosis and is associated with the worst clinical outcomes in patients with CAD, independently of atherosclerotic plaque features.