Dysfunctional High-Density Lipoproteins Are Associated With a Greater Incidence of Acute Coronary Syndrome in a Population at High Cardiovascular Risk: A Nested Case-Control Study

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.

Metabolomics Characterization of Disease Markers in Diabetes and Its Associated Pathologies

With the change in lifestyle of people, there has been a considerable increase in diabetes, which brings with it certain follow-up pathological conditions, which lead to a substantial medical burden. Identifying biomarkers that aid in screening, diagnosis, and prognosis of diabetes and its associated pathologies would help better patient management and facilitate a personalized treatment approach for prevention and treatment. With the advancement in techniques and technologies, metabolomics has emerged as an omics approach capable of large-scale high throughput data analysis and identifying and quantifying metabolites that provide an insight into the underlying mechanism of the disease and its progression. Diabetes and metabolomics keywords were searched in correspondence with the assigned keywords, including kidney, cardiovascular diseases and critical illness from PubMed and Scopus, from its inception to Dec 2023. The relevant studies from this search were extracted and included in the study. This review is focused on the biomarkers identified in diabetes, diabetic kidney disease, diabetes-related development of CVD, and its role in critical illness.

High-density lipoprotein functionality, cardiovascular health, and patterns of alcohol consumption: new insights and future perspectives

PURPOSE OF REVIEW

Cardiovascular diseases (CVD) pose a significant public health challenge, contributing to 422 million disability-adjusted life years in 2021. The role of high-density lipoproteins (HDL) and alcohol consumption, one of their major modifiable determinants, remains controversial. The objective of this review is to provide a comprehensive narrative overview of HDL functionality and its predictive value for CVD in relation to patterns of alcohol consumption.

RECENT FINDINGS

HDL phenotypes beyond HDL-cholesterol (HDL-c) such as distribution of HDL subspecies, HDL particle abundance, and reverse cholesterol transport capacity are promising indicators of atherosclerotic CVD risk. Low-to-moderate alcohol consumption seems to improve HDL functionality and reduce the incidence of CVD among primarily middle-aged men and postmenopausal women. Advancements in our understanding of HDL biogenesis, structure, and function hold promise for improving HDL-related measures and their predictive value for cardiovascular health.

SUMMARY

Low-to-moderate alcohol consumption appears to not only increase HDL-c concentration found in the HDL fraction of plasma but also enhance HDL functionality, providing insights into the underlying mechanisms linking alcohol exposure and cardiovascular health benefits. However, rigorous, well designed intervention trials of alcohol consumption on hard cardiovascular outcomes are needed to identify robust causal associations of HDL phenotypes and alcohol consumption with cardiovascular risk.

The pathophysiology of excess plasma-free cholesterol

PURPOSE OF REVIEW

Several large studies have shown increased mortality due to all-causes and to atherosclerotic cardiovascular disease. In most clinical settings, plasma HDL-cholesterol is determined as a sum of free cholesterol and cholesteryl ester, two molecules with vastly different metabolic itineraries. We examine the evidence supporting the concept that the pathological effects of elevations of plasma HDL-cholesterol are due to high levels of the free cholesterol component of HDL-C.

RECENT FINDINGS

In a small population of humans, a high plasma HDL-cholesterol is associated with increased mortality. Similar observations in the HDL-receptor deficient mouse (Scarb1 -/- ), a preclinical model of elevated HDL-C, suggests that the pathological component of HDL in these patients is an elevated plasma HDL-FC.

SUMMARY

Collective consideration of the human and mouse data suggests that clinical trials, especially in the setting of high plasma HDL, should measure free cholesterol and cholesteryl esters and not just total cholesterol.

Sex-Specific Relationships between HDL-Cholesterol Levels and 10-Year Mortality in Individuals with Atherosclerotic Cardiovascular Disease: A Nationwide Cohort Study of South Koreans

Large epidemiological studies show U-shaped relationships between high-density lipoprotein cholesterol (HDL-C) levels and all-cause mortality in individuals without atherosclerotic cardiovascular diseases (ASCVD). Association in those with ASCVD by sex is unclear. We examined the association between HDL-C levels and 10-year all-cause mortality in subjects (≥40 years of age) with ASCVD using the 2010 National Health Insurance Service and the National Death Registry of Korea. We categorized HDL-C levels into three groups (low: <40 mg/dL for males, <50 mg/dL for females; high: 40-90 mg/dL for males, 50-90 mg/dL for females; extremely high: >90 mg/dL) and 10 mg/dL intervals. We conducted a sex-stratified and adjusted Cox proportional hazards analysis. Out of 1,711,548 individuals (54% female, mean age 61.4 years), 10-year mortality was observed in 218,252 (12.8%). Males had a higher mortality rate than females (16.2% vs. 9.8%; p < 0.001). When adjusting for age, body mass index, LDL-cholesterol, triglycerides, hypertension, diabetes, smoking, and alcohol consumption, the low and extremely high HDL-C groups had significantly higher hazard ratios for 10-year mortality compared to the high HDL-C group in males [1.183 (1.166-1.199), 1.359 (1.288-1.434)] and in females [1.153 (1.138-1.169), 1.095 (1.029-1.167)]. The frequency distribution bars for the 10-year mortality rate showed sex-specific nadirs of 50-59 mg/dL in males and 70-79 mg/dL in females. In this ASCVD cohort, the extremely high HDL-C (>90 mg/dL) group had 35.9% and 9.5% higher 10-year mortality risks than the high HDL-C group for males and females, respectively. There was a slightly U-shaped relationship between baseline HDL-C levels and a 10-year mortality rate, with earlier inflection in males than in females.

San-wei-tan-xiang capsule attenuates atherosclerosis by increasing lysosomal activity in adipose tissue macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Dyslipidemia is the leading risk factor of atherosclerosis (AS). Adipose tissue macrophages (ATMs) can regulate postprandial cholesterol levels via uptake and hydrolyzation of lipids and regulation of macrophage cholesterol efflux (MCE). San-wei-tan-xiang (SWTX) capsule, a Traditional Chinese medicine, exerts clinical benefits in patients with atherosclerotic cardiovascular diseases.

AIM OF THE STUDY

This work is aimed to evaluate the chemical ingredients and mechanisms of SWTX in anti-AS.

MATERIALS AND METHODS

The chemical ingredients of SWTX identified by liquid chromatography coupled with tandem mass spectrometry were used for network pharmacological analysis. The atheroprotective function of SWTX was evaluated in ApoE^-/- mice fed a cholesterol-enriched diet.

RESULTS

The chemical ingredients identified in SWTX were predicated to be important for lipid metabolism and AS. Animals studies suggested that SWTX effectively attenuated the atherosclerotic plaque growth, elevated postprandial HDL cholesterol levels, elevated the proportion of Tim4 and CD36-expressed ATMs, and upregulated the uptake of lipid and lysosomal activity in ATMs. SWTX-induced elevation of postprandial HDL cholesterol levels was dependent on increased lysosomal activity, since chloroquine, an inhibitor of lysosomal function, blocked the effect of SWTX. Lastly, some predicated bioactive compounds in SWTX can elevate lysosomal activity in vitro.

CONCLUSION

SWTX could attenuate atherosclerotic plaque formation by elevating lysosomal activity and enhancing MCE in ATMs.

Efficient Metabolic Fingerprinting of Follicular Fluid Encodes Ovarian Reserve and Fertility

Ovarian reserve (OR) and fertility are critical in women's healthcare. Clinical methods for encoding OR and fertility rely on the combination of tests, which cannot serve as a multi-functional platform with limited information from specific biofluids. Herein, metabolic fingerprinting of follicular fluid (MFFF) from follicles is performed, using particle-assisted laser desorption/ionization mass spectrometry (PALDI-MS) to encode OR and fertility. PALDI-MS allows efficient MFFF, showing fast speed (≈30 s), high sensitivity (≈60 fmol), and desirable reproducibility (coefficients of variation <15%). Further, machine learning of MFFF is applied to diagnose diminished OR (area under the curve of 0.929) and identify high-quality oocytes/embryos (p < 0.05) by a single PALDI-MS test. Meanwhile, metabolic biomarkers from MFFF are identified, which also determine oocyte/embryo quality (p < 0.05) from the sampling follicles toward fertility prediction in clinics. This approach offers a powerful platform in women's healthcare, not limited to OR and fertility.

Proteomic and functional analysis of HDL subclasses in humans and rats: a proof-of-concept study

BACKGROUND

The previous study investigated whether the functions of small, medium, and large high density lipoprotein (S/M/L-HDL) are correlated with protein changes in mice. Herein, the proteomic and functional analyses of high density lipoprotein (HDL) subclasses were performed in humans and rats.

METHODS

After purifying S/M/L-HDL subclasses from healthy humans (n = 6) and rats (n = 3) using fast protein liquid chromatography (FPLC) with calcium silica hydrate (CSH) resin, the proteomic analysis by mass spectrometry was conducted, as well as the capacities of cholesterol efflux and antioxidation was measured.

RESULTS

Of the 120 and 106 HDL proteins identified, 85 and 68 proteins were significantly changed in concentration among the S/M/L-HDL subclasses in humans and rats, respectively. Interestingly, it was found that the relatively abundant proteins in the small HDL (S-HDL) and large HDL (L-HDL) subclasses did not overlap, both in humans and in rats. Next, by searching for the biological functions of the relatively abundant proteins in the HDL subclasses via Gene Ontology, it was displayed that the relatively abundant proteins involved in lipid metabolism and antioxidation were enriched more in the medium HDL (M-HDL) subclass than in the S/L-HDL subclasses in humans, whereas in rats, the relatively abundant proteins associated with lipid metabolism and anti-oxidation were enriched in M/L-HDL and S/M-HDL, respectively. Finally, it was confirmed that M-HDL and L-HDL had the highest cholesterol efflux capacity among the three HDL subclasses in humans and rats, respectively; moreover, M-HDL exhibited higher antioxidative capacity than S-HDL in both humans and rats.

CONCLUSIONS

The S-HDL and L-HDL subclasses are likely to have different proteomic components during HDL maturation, and results from the proteomics-based comparison of the HDL subclasses may explain the associated differences in function.

Lipoprotein Particle Profiles Associated with Telomere Length and Telomerase Complex Components

Telomere length (TL) is a well-known marker of age-related diseases. Oxidative stress and inflammation increase the rate of telomere shortening, triggering cellular senescence. Although lipoproteins could have anti-inflammatory and proinflammatory functional properties, the relationship between lipoprotein particles with TL and telomerase activity-related genes has not been investigated much. In this study, we assessed the associations of lipoprotein subfractions with telomere length, TERT, and WRAP53 expression in a total of 54 pre-diabetic subjects from the EPIRDEM study. We regressed TL, TERT, and WRAP53 on 12 lipoprotein subclasses, employing a Gaussian linear regression method with Lasso penalty to determine a lipoprotein profile associated with telomere-related parameters. The covariates included age, sex, body mass index (BMI), dyslipidemia, statin consumption, and physical activity leisure time. We identified a lipoprotein profile composed of four lipoprotein subfractions associated with TL (Pearson r = 0.347, p-value = 0.010), two lipoprotein subfractions associated with TERT expression (Pearson r = 0.316, p-value = 0.020), and five lipoprotein subfractions associated with WRAP53 expression (Pearson r = 0.379, p-value =0.005). After adjusting for known confounding factors, most lipoprotein profiles maintained the association with TL, TERT, and WRAP53. Overall, medium and small-sized HDL particles were associated with shorter telomeres and lower expression of TERT and WRAP53. Large HDL particles were associated with longer telomere and lower expression of WRAP53, but not with TERT. Our results suggest that the lipoprotein profiles are associated with telomere length, TERT, and WRAP53 expression and should be considered when assessing the risk of chronic diseases.

A Nutraceutical Compound Containing a Low Dose of Monacolin K, Polymethoxyflavones, Phenolic Acids, Flavonoids, and Hydroxytyrosol Improves HDL Functionality

BACKGROUND

In earlier studies, it has been observed that 8-week treatment with a novel nutraceutical compound (NC) containing low monacolin K dose, polymethoxyflavones, phenolic acids, flavonoids, and hydroxytyrosol improves lipid profile and endothelial function and reduces the level of oxidized low-density lipoprotein (oxLDL). We hypothesize that this effect might be, at least in part, explained by positive modulation exerted by the NC on the atheroprotective function of high-density lipoprotein (HDL).

AIM

This study aimed to evaluate whether the NC could influence determinants of HDL function.

METHODS

Forty-five subjects with low-moderate dyslipidaemia were enrolled and treated for 8 weeks with the NC, followed by 4 weeks of washout. Blood samples were collected at every time point to evaluate changes in lipid profile, endothelial function, oxLDL, and markers of HDL function, such as the anti-oxidant activities of paraoxonase-1, glutathione peroxidase-3 (Gpx3), lipoprotein-phospholipase A2 (Lp-PLA2), and pro-oxidant activity of myeloperoxidase (MPO).

RESULTS

Although the concentration of HDL-C did not change, the activity of Lp-PLA2 significantly decreased upon treatment (-11.6%, p<0.001) and returned to baseline level 4 weeks after the end of treatment. In contrast, Gpx3 increased after treatment (+5%, p<0.01) and remained unvaried after 4 weeks. Both MPO activity and concentration significantly decreased after the washout period (-33 and 32%, p<0.001).

CONCLUSION

For the first time, it was found that the administration of an NC with beneficial effects on lipid homeostasis also positively impacts HDL function by improving the balance between protective and damaging determinants. Further investigation is required to corroborate our findings.

Mediterranean Diet, Energy Restriction, Physical Activity, and Atherogenicity of Very-Low Density Lipoproteins: Findings from Two Randomized Controlled Trials

SCOPE

Some very-low density lipoprotein (VLDL) properties may render them more pro-atherogenic. We aimed to assess whether a Mediterranean diet (MedDiet) or an energy-reduced MedDiet with increased physical activity improves them.

METHODS AND RESULTS

In a sample of the PREvención con DIeta MEDiterránea (PREDIMED) study, a 1-year intervention with MedDiet with extra-virgin olive oil (n = 89) or nuts (MedDiet-Nuts; n = 79) is compared with a low-fat diet (n = 90). In the PREDIMED-Plus study, a 1-year intervention with energy-reduced MedDiet and physical activity (n = 103) is compared with an ad libitum MedDiet (n = 101). VLDL levels of apolipoprotein C-I, C-III, triglycerides, and cholesterol; the apolipoprotein E-/C-I ratio; and VLDL ex-vivo triglyceride transfer are measured. In PREDIMED participants in both MedDiet groups combined, VLDL apolipoprotein C-III levels are nominally reduced (-0.023 SD units, 95% CI -0.44 to -0.014, p = 0.037). VLDL triglyceride transfer is nominally increased in the MedDiet-Nuts group (+0.39 SD units, 95% CI 0.012-0.78, p = 0.045). In PREDIMED-Plus, no inter-group differences are detected.

CONCLUSIONS

In older adults at high cardiovascular risk, MedDiet is associated with lower VLDL atherogenicity versus a low-fat diet. No differences are seen after an energy-reduced MedDiet with physical activity.

High-density lipoprotein subclasses and cardiovascular disease and mortality in type 2 diabetes: analysis from the Hong Kong Diabetes Biobank

OBJECTIVE

High-density lipoproteins (HDL) comprise particles of different size, density and composition and their vasoprotective functions may differ. Diabetes modifies the composition and function of HDL. We assessed associations of HDL size-based subclasses with incident cardiovascular disease (CVD) and mortality and their prognostic utility.

RESEARCH DESIGN AND METHODS

HDL subclasses by nuclear magnetic resonance spectroscopy were determined in sera from 1991 fasted adults with type 2 diabetes (T2D) consecutively recruited from March 2014 to February 2015 in Hong Kong. HDL was divided into small, medium, large and very large subclasses. Associations (per SD increment) with outcomes were evaluated using multivariate Cox proportional hazards models. C-statistic, integrated discrimination index (IDI), and categorial and continuous net reclassification improvement (NRI) were used to assess predictive value.

RESULTS

Over median (IQR) 5.2 (5.0-5.4) years, 125 participants developed incident CVD and 90 participants died. Small HDL particles (HDL-P) were inversely associated with incident CVD [hazard ratio (HR) 0.65 (95% CI 0.52, 0.81)] and all-cause mortality [0.47 (0.38, 0.59)] (false discovery rate < 0.05). Very large HDL-P were positively associated with all-cause mortality [1.75 (1.19, 2.58)]. Small HDL-P improved prediction of mortality [C-statistic 0.034 (0.013, 0.055), IDI 0.052 (0.014, 0.103), categorical NRI 0.156 (0.006, 0.252), and continuous NRI 0.571 (0.246, 0.851)] and CVD [IDI 0.017 (0.003, 0.038) and continuous NRI 0.282 (0.088, 0.486)] over the RECODe model.

CONCLUSION

Small HDL-P were inversely associated with incident CVD and all-cause mortality and improved risk stratification for adverse outcomes in people with T2D. HDL-P may be used as markers for residual risk in people with T2D.

Cholesterol mass efflux capacity and coronary artery calcium: The Multi-Ethnic Study of Atherosclerosis

We assessed the cross-sectional and longitudinal relationships of high-density lipoprotein (HDL)-mediated cholesterol mass efflux capacity (CMEC) with coronary artery calcium (CAC) score and CAC density. CMEC was measured in 1626 Multi-Ethnic Study of Atherosclerosis (MESA) participants in samples obtained between 2000 and 2002 as part of two nested case-control studies, one with cases of incident cardiovascular disease and the other with cases of carotid plaque progression by ultrasound. Cardiac CT examinations for the presence of CAC were performed at baseline and at two additional examinations. CAC scores (Agatston and volume) and density scores (for those with positive CAC) were calculated. Multivariable linear regression modeling per SD increment of CMEC was used to estimate the associations of CMEC with each of these CAC measures. We found no association between higher CMEC and either lower CAC scores or a higher CAC density. We also found no association between higher CMEC and progression of any of these CAC measures. These findings suggest that HDL-mediated cholesterol efflux may be associated with cardiovascular risk via mechanisms unrelated to burden of calcified plaque.

Effects of PCSK9 inhibitors on HDL cholesterol efflux and serum cholesterol loading capacity in familial hypercholesterolemia subjects: a multi-lipid-center real-world evaluation

Proprotein convertase subtilisin/kexin type 9 (PCSK9), beyond regulating LDL cholesterol (LDL-c) plasma levels, exerts several pleiotropic effects by modulating lipid metabolism in extrahepatic cells such as macrophages. Macrophage cholesterol homeostasis depends on serum lipoprotein functions, including the HDL capacity to promote cell cholesterol efflux (CEC) and the serum capacity to promote cell cholesterol loading (CLC). The aim of this observational study was to investigate the effect of PCSK9 inhibitors (PCSK9-i) treatment on HDL-CEC and serum CLC in patients with familial hypercholesterolemia (FH). 31 genetically confirmed FH patients were recruited. Blood was collected and serum isolated at baseline and after 6 months of PCSK9-i treatment. HDL-CEC was evaluated through the main pathways with a radioisotopic cell-based assay. Serum CLC was assessed fluorimetrically in human THP-1 monocyte-derived macrophages. After treatment with PCSK9-i, total cholesterol and LDL-c significantly decreased (−41.6%, p < 0.0001 and −56.7%, p < 0.0001, respectively). Total HDL-CEC was not different between patients before and after treatment. Conversely, despite no changes in HDL-c levels between the groups, ABCG1 HDL-CEC significantly increased after treatment (+22.2%, p < 0.0001) as well as HDL-CEC by aqueous diffusion (+7.8%, p = 0.0008). Only a trend towards reduction of ABCA1 HDL-CEC was observed after treatment. PCSK9-i significantly decreased serum CLC (−6.6%, p = 0.0272). This effect was only partly related to the reduction of LDL-c levels. In conclusion, PCSK9-i treatment significantly increased HDL-CEC through ABCG1 and aqueous diffusion pathways and reduced the serum CLC in FH patients. The favorable effect of PCSK9-i on functional lipid profile could contribute to the cardiovascular benefit of these drugs in FH patients.

Differential Effects of Genetically Determined Cholesterol Efflux Capacity on Coronary Artery Disease and Ischemic Stroke

Background

Observational studies indicated that cholesterol efflux capacity (CEC) of high-density lipoprotein (HDL) is inversely associated with cardiovascular events, independently of the HDL cholesterol concentration. The aim of the study is to examine the casual relevance of CEC for coronary artery disease (CAD) and myocardial infarction (MI), and compare it with that for ischemic stroke and its subtypes using a Mendelian randomization approach.

Methods

We performed a 2-sample Mendelian randomization to estimate the casual relationship of CEC with the risk of CAD, MI, and ischemic stroke. A CEC-related genetic variant (rs141622900) and other five genetic variants were used as the instrumental variables. Association of genetic variants with CAD were estimated in a GWAS involving 60,801 CAD cases and 123,504 controls. They were then compared with the associations of these variants with ischemic stroke and its subtypes (large vessel, small vessel, and cardioembolic) involving 40,585 ischemic stroke cases and 406,111 controls.

Results

Using the SNP of rs141622900 as the instrument, a 1-SD increase in CEC was associated with 45% lower risk for CAD (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.44–0.69, p < 0.001) and 33% lower risk for MI (odds ratio [OR] 0.67, 95% CI 0.52–0.87, p = 0.002). By contrast, the causal effect of CEC was much weaker for ischemic stroke (odds ratio [OR] 0.79, 95% CI 0.64–0.97, p = 0.02; p for heterogeneity = 0.03) and, in particular, for cardioembolic stroke (p for heterogeneity = 0.006) when compared with that for CAD. Results using five genetic variants as the instrument also indicated consistently weaker effects on ischemic stroke than on CAD.

Conclusion

Genetic predicted higher CEC may be associated with decreased risk of CAD. However, the casual association of CEC with ischemic stroke and specific subtypes would need to be validated in further Mendelian randomization studies.

New insight into dyslipidemia‐induced cellular senescence in atherosclerosis

Atherosclerosis, characterized by lipid‐rich plaques in the arterial wall, is an age‐related disorder and a leading cause of mortality worldwide. However, the specific mechanisms remain complex. Recently, emerging evidence has demonstrated that senescence of various types of cells, such as endothelial cells (ECs), vascular smooth muscle cells (VSMCs), macrophages, endothelial progenitor cells (EPCs), and adipose‐derived mesenchymal stem cells (AMSCs) contributes to atherosclerosis. Cellular senescence and atherosclerosis share various causative stimuli, in which dyslipidemia has attracted much attention. Dyslipidemia, mainly referred to elevated plasma levels of atherogenic lipids or lipoproteins, or functional impairment of anti‐atherogenic lipids or lipoproteins, plays a pivotal role both in cellular senescence and atherosclerosis. In this review, we summarize the current evidence for dyslipidemia‐induced cellular senescence during atherosclerosis, with a focus on low‐density lipoprotein (LDL) and its modifications, hydrolysate of triglyceride‐rich lipoproteins (TRLs), and high‐density lipoprotein (HDL), respectively. Furthermore, we describe the underlying mechanisms linking dyslipidemia‐induced cellular senescence and atherosclerosis. Finally, we discuss the senescence‐related therapeutic strategies for atherosclerosis, with special attention given to the anti‐atherosclerotic effects of promising geroprotectors as well as anti‐senescence effects of current lipid‐lowering drugs.

Associations of ATP-Sensitive Potassium Channel’s Gene Polymorphisms With Type 2 Diabetes and Related Cardiovascular Phenotypes

Type 2 diabetes (T2D) is characterized by increased levels of blood glucose but is increasingly recognized as a heterogeneous disease, especially its multiple discrete cardiovascular phenotypes. Genetic variations play key roles in the heterogeneity of diabetic cardiovascular phenotypes. This study investigates possible associations of ATP-sensitive potassium channel (KATP) variants with cardiovascular phenotypes among the Chinese patients with T2D. Six hundred thirty-six patients with T2D and 634 non-diabetic individuals were analyzed in the study. Nine KATP variants were determined by MassARRAY. The KATP rs2285676 (AA + GA, OR = 1.43, 95% CI: 1.13–1.81, P = 0.003), rs1799858 (CC, OR = 1.42, 95% CI: 1.12–1.78, P = 0.004), and rs141294036 (CC, OR = 1.45, 95% CI: 1.15–1.83, P = 0.002) are associated with increased T2D risk. A follow-up of at least 45.8-months (median) indicates further association between the 3 variants and risks of diabetic-related cardiovascular conditions. The associations are categorized as follows: new-onset/recurrent acute coronary syndrome (ACS) (rs2285676/AA + GA, HR = 1.37, 95% CI: 1.10–1.70, P = 0.005; rs141294036/TT + CT, HR = 1.59, 95% CI: 1.28–1.99, P < 0.001), new-onset stroke (rs1799858/CC, HR = 2.58, 95% CI: 1.22–5.43, P = 0.013; rs141294036/CC, HR = 2.30, 95% CI: 1.16–4.55, P = 0.017), new-onset of heart failure (HF) (rs1799858/TT + CT, HR = 2.78, 95% CI: 2.07–3.74, P < 0.001; rs141294036/TT + CT, HR = 1.45, 95% CI: 1.07–1.96, P = 0.015), and new-onset atrial fibrillation (AF) (rs1799858/TT + CT, HR = 2.05, 95% CI: 1.25–3.37, P = 0.004; rs141294036/CC, HR = 2.31, 95% CI: 1.40–3.82, P = 0.001). In particular, the CC genotype of rs1799858 (OR = 2.38, 95% CI: 1.11–5.10, P = 0.025) and rs141294036 (OR = 1.95, 95% CI: 1.04–3.66, P = 0.037) are only associated with the risk of ischemic stroke while its counterpart genotype (TT + CT) is associated with the risks of HF with preserved ejection fraction (HFpEF) (rs1799858, OR = 3.46, 95% CI: 2.31–5.18, P < 0.001) and HF with mildly reduced ejection fraction (HFmrEF) (rs141294036, OR = 2.74, 95% CI: 1.05–7.15, P = 0.039). Furthermore, the 3 variants are associated with increased risks of abnormal serum levels of triglyceride (TIRG) (≥ 1.70 mmol/L), low-density lipoprotein cholesterol (LDL-C) (≥ 1.40 mmol/L), apolipoprotein B (ApoB) (≥ 80 mg/dL), apolipoprotein A-I (ApoA-I) level (< 120 mg/dL), lipoprotein(a) Lp(a) (≥ 300 mg/dL) and high-sensitivity C-reactive protein (HsCRP) (≥ 3.0 mg/L) but exhibited heterogeneity (all P < 0.05). The KATP rs2285676, rs1799858, and rs141294036 are associated with increased risks of T2D and its related cardiovascular phenotypes (ACS, stroke, HF, and AF), but show heterogeneity. The 3 KATP variants may be promising markers for diabetic cardiovascular events favoring “genotype-phenotype” oriented prevention and treatment strategies.

LncRNAs and Cardiovascular Disease

A novel class of RNA molecule emerged from human transcriptome sequencing studies termed long non-coding RNAs. These RNA molecules differ from other classes of non-coding RNAs such as microRNAs in their sizes, sequence motifs and structures. Studies have demonstrated that long non-coding RNAs play a prominent role in the development and progression of cardiovascular disease. They provide the cell with tiered levels of gene regulation interacting with DNA, other RNA molecules or proteins acting in various capacities to control a variety of cellular mechanisms. Cell specificity is a hallmark of lncRNA studies and they have been identified in macrophages, smooth muscle cells, endothelial cells and hepatocytes. Recent lncRNA studies have uncovered functional micropeptides encoded within lncRNA genes that can have a different function to the lncRNA. Disease associated mutations in the genome tend to occur in non-coding regions signifying the importance of non-coding genes in disease associations. There is a great deal of work to be done in the non-coding RNA field and tremendous therapeutic potential due to their cell type specificity. A better understanding of the functions and interactions of lncRNAs will inevitably have clinical implications.

Cross-Sectional Associations between HDL Structure or Function, Cell Membrane Fatty Acid Composition, and Inflammation in Elderly Adults

BACKGROUND

Cell membrane fatty acid composition has been related to inflammation and cardiovascular disease (CVD) risk. Dysregulation of HDL function is also considered a CVD risk factor.

OBJECTIVES

We aimed to investigate whether the content of cell membrane fatty acids and HDL functionality are linked to each other as well as to inflammation.

METHODS

This cross-sectional analysis involved 259 participants (mean age: 67.9 y) with overweight/obesity (mean BMI: 29.5 kg/m2) from a coronary artery disease case-control study nested within the PREDIMED (PREvención con DIeta MEDiterránea) trial for which HDL functional parameters [apoA-I, apoA-IV, and apoC-III; cholesterol efflux capacity (CEC); HDL oxidative inflammatory index (HOII); sphingosine-1-phosphate (S1P); serum amyloid A (SAA); and complement-3 (C3) protein] were quantified. We also assessed 22 fatty acids in blood cell membranes using GC and inflammatory markers (IFN-γ and IL-1b, IL-6, IL-8, and IL-10) in serum. Associations of HDL-related variables with cell membrane fatty acids and with inflammatory markers were assessed using multivariable linear regression analyses with elastic net penalty.

RESULTS

ApoA-I, apoC-III, CEC, HOII, S1P, and SAA, but not apoA-IV and C3 protein, were associated with membrane fatty acids. S1P and SAA were directly associated with IL-6, whereas apoA-I and C3 protein showed inverse associations with IL-6. Specific fatty acids including myristic acid (14:0) and long-chain n-6 fatty acids being negatively and positively associated with IL-8, respectively, were also found to be positively associated with SAA.

CONCLUSIONS

This study suggests interrelations between indicators of inflammation and both blood cell membrane fatty acid composition and HDL structure/functional parameters in a Mediterranean population at high CVD risk.This trial was registered at www.isrctn.com as ISRCTN35739639.

A New Look at Novel Cardiovascular Risk Biomarkers: The Role of Atherogenic Lipoproteins and Innovative Antidiabetic Therapies

The presence of residual cardiovascular disease (CVD) risk is a current dilemma in clinical practice; indeed, despite optimal management and treatment, a considerable proportion of patients still undergo major CV events. Novel lipoprotein biomarkers are suggested as possible targets for improving the outcomes of patients at higher risk for CVD, and their impact on major CV events and mortality have previously been investigated. Innovative antidiabetic therapies have recently shown a significant reduction in atherogenic lipoproteins, beyond their effects on glucose parameters; it has also been suggested that such anti-atherogenic effect may represent a valuable mechanistic explanation for the cardiovascular benefit of, at least, some of the novel antidiabetic agents, such as glucagon-like peptide-1 receptor agonists. This emphasizes the need for further research in the field in order to clearly assess the effects of innovative treatments on different novel biomarkers, including atherogenic lipoproteins, such as small dense low-density lipoprotein (LDL), lipoprotein(a) (Lp(a)) and dysfunctional high-density lipoprotein (HDL). The current article discusses the clinical importance of novel lipid biomarkers for better management of patients in order to overcome residual cardiovascular risk.

Modification of High-Density Lipoprotein Functions by Diet and Other Lifestyle Changes: A Systematic Review of Randomized Controlled Trials

High-density lipoprotein (HDL) functional traits have emerged as relevant elements that may explain HDL antiatherogenic capacity better than HDL cholesterol levels. These properties have been improved in several lifestyle intervention trials. The aim of this systematic review is to summarize the results of such trials of the most commonly used dietary modifications (fatty acids, cholesterol, antioxidants, alcohol, and calorie restriction) and physical activity. Articles were screened from the Medline database until March 2021, and 118 randomized controlled trials were selected. Results from HDL functions and associated functional components were extracted, including cholesterol efflux capacity, cholesteryl ester transfer protein, lecithin-cholesterol acyltransferase, HDL antioxidant capacity, HDL oxidation status, paraoxonase-1 activity, HDL anti-inflammatory and endothelial protection capacity, HDL-associated phospholipase A2, HDL-associated serum amyloid A, and HDL-alpha-1-antitrypsin. In mainly short-term clinical trials, the consumption of monounsaturated and polyunsaturated fatty acids (particularly omega-3 in fish), and dietary antioxidants showed benefits to HDL functionality, especially in subjects with cardiovascular risk factors. In this regard, antioxidant-rich dietary patterns were able to improve HDL function in both healthy individuals and subjects at high cardiovascular risk. In addition, in randomized trial assays performed mainly in healthy individuals, reverse cholesterol transport with ethanol in moderate quantities enhanced HDL function. Nevertheless, the evidence summarized was of unclear quality and short-term nature and presented heterogeneity in lifestyle modifications, trial designs, and biochemical techniques for the assessment of HDL functions. Such findings should therefore be interpreted with caution. Large-scale, long-term, randomized, controlled trials in different populations and individuals with diverse pathologies are warranted.

High-density lipoprotein cholesterol to apolipoprotein A1 ratio and all-cause mortality among incident peritoneal dialysis patients

BACKGROUND AND AIMS

The ratio of high-density lipoprotein cholesterol to apolipoprotein A1 (HAR) is associated with all-cause mortality in nonchronic kidney disease patients, but its role in predicting all-cause mortality in patients undergoing peritoneal dialysis (PD) is still unclear. The purpose of this study was to investigate the relationship between HAR and all-cause mortality in patients with PD.

METHODS AND RESULTS

The medical records of 1199 patients with PD from November 1, 2005, to August 31, 2019, were collected retrospectively. The main outcome was defined as all-cause mortality. The HAR was divided into three groups by X-tile software. The association between HAR and all-cause mortality was evaluated by Cox models. The Kaplan-Meier method was used for the survival curve. The median follow-up period was 35 months (interquartile range: 20-57 months), with a total of 326 deaths recorded. After multiple adjustments, the risk of all-cause mortality in the high HAR group was 1.96-fold higher than that in the low HAR group (hazard ratio: 1.96; 95% CI, 1.22 to 3.15; P = 0.005). The restricted cubic splines showed that the risk of all-cause mortality increased gradually when HAR was >0.37. In the stratified analysis, a high HAR was linked to a high risk of all-cause mortality in males, patients under 55 years old, and patients without diabetes or cardiovascular disease (CVD).

CONCLUSION

This study suggests that HAR is independently related to all-cause mortality in PD patients, especially in males, patients under 55 years old, and patients without diabetes or CVD.

Obesity-Associated Metabolic Disturbances Reverse the Antioxidant and Anti-Inflammatory Properties of High-Density Lipoproteins in Microglial Cells

High-density lipoproteins (HDLs) play an important role in reverse cholesterol transport and present antioxidant properties, among others. In the central nervous system (CNS), there are HDLs, where these lipoproteins could influence brain health. Owing to the new evidence of HDL functionality remodeling in obese patients, and the fact that obesity-associated metabolic disturbances is pro-inflammatory and pro-oxidant, the aim of this study was to investigate if HDL functions are depleted in obese patients and obesity-associated microenvironment. HDLs were isolated from normal-weight healthy (nwHDL) and obese men (obHDL). The oxHDL level was measured by malondialdehyde and 4-hydroxynoneal peroxided products. BV2 microglial cells were exposed to different concentrations of nwHDL and obHDL in different obesity-associated pro-inflammatory microenvironments. Our results showed that hyperleptinemia increased oxHDL levels. In addition, nwHDLs reduced pro-inflammatory cytokines’ release and M1 marker gene expression in BV2 microglial cells. Nevertheless, both nwHDL co-administered with LPS+leptin and obHDL promoted BV2 microglial activation and a higher pro-inflammatory cytokine production, thus confirming that obesity-associated metabolic disturbances reverse the antioxidant and anti-inflammatory properties of HDLs in microglial cells.

A lifestyle intervention with an energy-restricted Mediterranean diet and physical activity enhances HDL function: a substudy of the PREDIMED-Plus randomized controlled trial

BACKGROUND

Consumption of a Mediterranean diet, adequate levels of physical activity, and energy-restricted lifestyle interventions have been individually associated with improvements in HDL functions. Evidence of intensive interventions with calorie restriction and physical activity is, however, scarce.

OBJECTIVES

To determine whether an intensive lifestyle intervention with an energy-restricted Mediterranean diet plus physical activity enhanced HDL function compared to a non-hypocaloric Mediterranean eating pattern without physical activity.

METHODS

In 391 older adults with metabolic syndrome (mean age, 65 years; mean BMI, 33.3 kg/m2) from 1 of the Prevención con Dieta Mediterránea-Plus trial centers, we evaluated the impact of a 6-month intervention with an energy-restricted Mediterranean diet plus physical activity (intensive lifestyle; n = 190) relative to a nonrestrictive Mediterranean diet without physical activity (control; n = 201) on a set of HDL functional traits. These included cholesterol efflux capacity, HDL oxidative/inflammatory index, HDL oxidation, and levels of complement component 3, serum amyloid A, sphingosine-1-phosphate, triglycerides, and apolipoproteins A-I, A-IV, C-III, and E in apoB-depleted plasma.

RESULTS

The intensive-lifestyle intervention participants displayed greater 6-month weight reductions (-3.83 kg; 95% CI: -4.57 to -3.09 kg) but no changes in HDL cholesterol compared with control-diet participants. Regarding HDL functional traits, the intensive lifestyle decreased triglyceride levels (-0.15 mg/g protein; 95% CI: -0.29 to -0.014 mg/g protein) and apoC-III (-0.11 mg/g protein; 95% CI: -0.18 to -0.026 mg/g protein) compared to the control diet, with weight loss being the essential mediator (proportions of mediation were 77.4% and 72.1% for triglycerides and apoC-III levels in HDL, respectively).

CONCLUSIONS

In older adults with metabolic syndrome, an energy-restricted Mediterranean diet plus physical activity improved the HDL triglyceride metabolism compared with a nonrestrictive Mediterranean diet without physical activity. This trial is registered at isrctn.com as ISRCTN89898870.

Metabolomics in Diabetes and Diabetic Complications: Insights from Epidemiological Studies

The increasing prevalence of diabetes and its complications, such as cardiovascular and kidney disease, remains a huge burden globally. Identification of biomarkers for the screening, diagnosis, and prognosis of diabetes and its complications and better understanding of the molecular pathways involved in the development and progression of diabetes can facilitate individualized prevention and treatment. With the advancement of analytical techniques, metabolomics can identify and quantify multiple biomarkers simultaneously in a high-throughput manner. Providing information on underlying metabolic pathways, metabolomics can further identify mechanisms of diabetes and its progression. The application of metabolomics in epidemiological studies have identified novel biomarkers for type 2 diabetes (T2D) and its complications, such as branched-chain amino acids, metabolites of phenylalanine, metabolites involved in energy metabolism, and lipid metabolism. Metabolomics have also been applied to explore the potential pathways modulated by medications. Investigating diabetes using a systems biology approach by integrating metabolomics with other omics data, such as genetics, transcriptomics, proteomics, and clinical data can present a comprehensive metabolic network and facilitate causal inference. In this regard, metabolomics can deepen the molecular understanding, help identify potential therapeutic targets, and improve the prevention and management of T2D and its complications. The current review focused on metabolomic biomarkers for kidney and cardiovascular disease in T2D identified from epidemiological studies, and will also provide a brief overview on metabolomic investigations for T2D.

High-density lipoproteins, reverse cholesterol transport and atherogenesis

Plasma HDL-cholesterol concentrations correlate negatively with the risk of atherosclerotic cardiovascular disease (ASCVD). According to a widely cited model, HDL elicits its atheroprotective effect through its role in reverse cholesterol transport, which comprises the efflux of cholesterol from macrophages to early forms of HDL, followed by the conversion of free cholesterol (FCh) contained in HDL into cholesteryl esters, which are hepatically extracted from the plasma by HDL receptors and transferred to the bile for intestinal excretion. Given that increasing plasma HDL-cholesterol levels by genetic approaches does not reduce the risk of ASCVD, the focus of research has shifted to HDL function, especially in the context of macrophage cholesterol efflux. In support of the reverse cholesterol transport model, several large studies have revealed an inverse correlation between macrophage cholesterol efflux to plasma HDL and ASCVD. However, other studies have cast doubt on the underlying reverse cholesterol transport mechanism: in mice and humans, the FCh contained in HDL is rapidly cleared from the plasma (within minutes), independently of esterification and HDL holoparticle uptake by the liver. Moreover, the reversibility of FCh transfer between macrophages and HDL has implicated the reverse process - that is, the transfer of FCh from HDL to macrophages - in the aetiology of increased ASCVD under conditions of very high plasma HDL-FCh concentrations.

High Free Cholesterol Bioavailability Drives the Tissue Pathologies in Scarb1-/- Mice

Objective: Overall and atherosclerosis-associated mortality is elevated in humans with very high HDL (high-density lipoprotein) cholesterol concentrations. Mice with a deficiency of the HDL receptor, Scarb1 (scavenger receptor class B type 1), are a robust model of this phenotype and exhibit several additional pathologies. We hypothesized that the previously reported high plasma concentration of free cholesterol (FC)-rich HDL in Scarb1-/- mice produces a state of high HDL-FC bioavailability that increases whole-body FC and dysfunction in multiple tissue sites. Approach and Results: The higher mol% FC in Scarb1-/- versus WT (wild type) HDL (41.1 versus 16.0 mol%) affords greater FC bioavailability for transfer to multiple sites. Plasma clearance of autologous HDL-FC mass was faster in WT versus Scarb1-/- mice. FC influx from Scarb1-/- HDL to LDL (low-density lipoprotein) and J774 macrophages was greater ([almost equal to]4x) than that from WT HDL, whereas FC efflux capacity was similar. The higher mol% FC of ovaries, erythrocytes, heart, and macrophages of Scarb1-/- versus WT mice is associated with previously reported female infertility, impaired cell maturation, cardiac dysfunction, and atherosclerosis. The FC contents of other tissues were similar in the two genotypes, and these tissues were not associated with any overt pathology. In addition to the differences between WT versus Scarb1-/- mice, there were many sex-dependent differences in tissue-lipid composition and plasma FC clearance rates. Conclusions: Higher HDL-FC bioavailability among Scarb1-/- versus WT mice drives increased FC content of multiple cell sites and is a potential biomarker that is mechanistically linked to multiple pathologies.

Analysis of Serum Interleukin-37 Level and Prognosis in Patients with ACS

Objective

To explore the level of serum interleukin-37 in patients with acute coronary syndrome (ACS) and its prognostic value.

Methods

Altogether, 121 continuous ACS cases from September 2017 to June 2020 were selected as the research group (RG), and 107 healthy individuals during the same period were obtained as the control group (CG). ELISA was applied to test IL-37 in the serum of the CG and the RG. Chemiluminescence immunoassay was applied to test NT-pro BNP and hs-cTnI in each group and immune scattering turbidimetry to test hs-CRP. The correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP was analyzed, and the value of IL-37 in diagnosis and prognosis prediction of patients with ACS was tested. Logistic regression was applied to test the independent risk factors affecting poor prognosis of patients with ACS.

Results

IL-37 was poorly expressed in patients with ACS, which had a high diagnostic value for ACS (sensitivity: 94.39%, specificity: 74.38%, and area under curve: 0.945). There was a negative correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP. IL-37 in patients with poor prognosis was markedly declined compared with that of patients with good prognosis, and the predicted AUC was 0.965. Logistic regression revealed that low IL-37, diabetes, high CRP, NT-pro BNP, and hs-cTnI in the blood were independent risk factors for poor prognosis in patients with ACS.

Conclusion

IL-37 is low expressed in patients with ACS, which has a good diagnostic and prognostic value for ACS, and may be applied as an important marker for the prediction of patients with ACS.

Serum Sphingosine-1-Phosphate Levels Are Associated With Severity and Outcome in Patients With Cerebral Ischemia

BACKGROUND AND PURPOSE

The aim of this study was to examine whether sphingosine-1-phosphate (S1P) levels in patients with acute stroke are associated with stroke severity and outcome.

METHODS

In a prospective stroke cohort (MARK-STROKE), 374 patients with acute ischemic stroke or transient ischemic attack were enrolled (mean age: 67.9±13.0 years, sex: 64.7% male), and serum-S1P at admission was analyzed with tandem mass spectrometry. In addition to cross-sectional analyses, 79 adverse events (death, stroke, myocardial infarction, rehospitalization) were recorded in 270 patients during follow-up. Regression analyses were adjusted for age, sex, low-density lipoprotein cholesterol, and vascular risk factors. Results were validated in an independent stroke cohort with 219 patients with acute ischemic stroke (CIRCULAS).

RESULTS

Low serum-S1P was associated with higher National Institutes of Health Stroke Scale score at admission and with anterior circulation nonlacunar infarcts determined by multivariate regression analyses. During a follow-up of 294±170 days, patients with S1P in the lowest tertile (<1.33 µmol/L) had more adverse events (Kaplan-Meier analysis, P=0.048 for trend). In adjusted Cox regression analysis, the lowest S1P tertile was associated with a worse outcome after stroke (hazard ratio, HR 0.51 [95% confidence interval 0.28-0.92]). Results were confirmed in an independent cohort, ie, low S1P levels were associated with higher National Institutes of Health Stroke Scale, larger infarct volumes and worse outcome after 90 days (β-coefficient: -0.03, P=0.026; β-coefficient: -0.099, P=0.009 and odds ratio 0.52 [0.28-0.96], respectively).

CONCLUSIONS

Our findings imply a detrimental role of low S1P levels in acute stroke and therefore underpin the therapeutic potential of S1P-mimics.

Is a High HDL-Cholesterol Level Always Beneficial?

The specific interest concerning HDL cholesterol (HDL-C) is related to its ability to uptake and return surplus cholesterol from peripheral tissues back to the liver and, therefore, to its role in the prevention of cardiovascular diseases, such as atherosclerosis and myocardial infarction, but also transient ischemic attack and stroke. Previous epidemiological studies have indicated that HDL-C concentration is inversely associated with the risk of cardiovascular disease and that it can be used for risk prediction. Some genetic disorders are characterized by markedly elevated levels of HDL-C; however, they do not translate into diminished cardiovascular risk. The search of the potential causative relationship between HDL-C and adverse events has shifted the attention of researchers towards the composition and function of the HDL molecule/subfractions. HDL possesses various cardioprotective properties. However, currently, it appears that higher HDL-C is not necessarily protective against cardiovascular disease, but it can even be harmful in extremely high quantities.

Dysfunctional High-Density Lipoproteins in Type 2 Diabetes Mellitus: Molecular Mechanisms and Therapeutic Implications

High density lipoproteins (HDLs) are commonly known for their anti-atherogenic properties that include functions such as the promotion of cholesterol efflux and reverse cholesterol transport, as well as antioxidant and anti-inflammatory activities. However, because of some chronic inflammatory diseases, such as type 2 diabetes mellitus (T2DM), significant changes occur in HDLs in terms of both structure and composition. These alterations lead to the loss of HDLs’ physiological functions, to transformation into dysfunctional lipoproteins, and to increased risk of cardiovascular disease (CVD). In this review, we describe the main HDL structural/functional alterations observed in T2DM and the molecular mechanisms involved in these T2DM-derived modifications. Finally, the main available therapeutic interventions targeting HDL in diabetes are discussed.

HDL-C/apoA-I Ratio Is Associated with the Severity of Coronary Artery Stenosis in Diabetic Patients with Acute Coronary Syndrome

Background

Emerging evidence demonstrates that the lipid metabolism in acute coronary syndrome (ACS) patients with type 2 diabetes mellitus (T2DM) differs from nondiabetic patients. However, the distinct lipid profiles and their relationships with the severity of coronary artery stenosis and prognosis in patients with T2DM remain elusive.

Method and Result

This single-center, prospective cohort study enrolled 468 patients diagnosed with ACS undergoing coronary angiography, consisting of 314 non-DM and 154 DM patients. The HDL-C/apoA-I ratio was significantly higher in DM patients with a multivessel (≥3 affected vessels) lesion than a single-vessel (1-2 affected vessels) lesion. Regression analyses showed that the HDL-C/apoA-I ratio was positively correlated to the number of stenotic coronary arteries in DM patients but not non-DM patients. However, Kaplan-Meier survival analysis revealed no significant difference in the major adverse cardiovascular event rate regarding different HDL-C/apoA-I levels in DM or non-DM ACS patients at the end of the 2-year follow-up.

Conclusion

A higher HDL-C/apoA-I ratio is associated with increased severity of coronary artery stenosis in DM patients with ACS but not with the rate of major adverse cardiovascular events at the end of the 2-year follow-up.

High Fruit and Vegetable Consumption and Moderate Fat Intake Are Associated with Higher Carotenoid Concentration in Human Plasma

Carotenoids are pigments contained mainly in fruit and vegetables (F&V) that have beneficial effects on cardiometabolic health. Due to their lipophilic nature, co-ingestion of fat appears to increase their bioavailability via facilitating transfer to the aqueous micellar phase during digestion. However, the extent to which high fat intake may contribute to increased carotenoid plasma concentrations is still unclear. The objective was to examine the degree to which the consumption of different amounts of both carotenoid-rich foods and fats is associated with plasma carotenoid concentrations within a Mediterranean lifestyle context (subsample from the PREDIMED-Plus study baseline) where consumption of F&V and fat is high. The study population was categorized into four groups according to their self-reported consumption of F&V and fat. Carotenoids were extracted from plasma samples and analyzed by HPLC-UV-VIS-QqQ-MS/MS. Carotenoid systemic concentrations were greater in high consumers of F&V than in low consumers of these foods (+3.04 μmol/L (95% CI: 0.90, 5.17), p-value = 0.005), but circulating concentrations seemed to decrease when total fat intake was very high (−2.69 μmol/L (−5.54; 0.16), p-value = 0.064). High consumption of F&V is associated with greater systemic levels of total carotenoids, in particular when fat intake is low-to-moderate rather than very high.

High-Density Lipoproteins and Mediterranean Diet: A Systematic Review

Cardiovascular disease (CVD) is the leading cause of global mortality and the study of high-density lipoproteins (HDL) particle composition and functionality has become a matter of high interest, particularly in light to the disappointing clinical data for HDL-cholesterol (HDL-C) raising therapies in CVD secondary prevention and the lack of association between HDL-C and the risk of CVD. Recent evidences suggest that HDL composition and functionality could be modulated by diet. The purpose of this systematic review was to investigate the effect of Mediterranean diet (MD) on changes in HDL structure and functionality in humans. A comprehensive search was conducted in four databases (PubMed, Scopus, Cochrane library and Web of Science) and 13 records were chosen. MD showed favorable effects on HDL functionality, particularly by improving HDL cholesterol efflux capacity and decreasing HDL oxidation. In addition, HDL composition and size were influenced by MD. Thus, MD is a protective factor against CVD associated with the improvement of HDL quality and the prevention of HDL dysfunctionality.

High Density Lipoprotein Cholesterol Efflux Capacity and Atherosclerosis in Cardiovascular Disease: Pathophysiological Aspects and Pharmacological Perspectives

Over the years, the relationship between high-density lipoprotein (HDL) and atherosclerosis, initially highlighted by the Framingham study, has been revealed to be extremely complex, due to the multiple HDL functions involved in atheroprotection. Among them, HDL cholesterol efflux capacity (CEC), the ability of HDL to promote cell cholesterol efflux from cells, has emerged as a better predictor of cardiovascular (CV) risk compared to merely plasma HDL-cholesterol (HDL-C) levels. HDL CEC is impaired in many genetic and pathological conditions associated to high CV risk such as dyslipidemia, chronic kidney disease, diabetes, inflammatory and autoimmune diseases, endocrine disorders, etc. The present review describes the current knowledge on HDL CEC modifications in these conditions, focusing on the most recent human studies and on genetic and pathophysiologic aspects. In addition, the most relevant strategies possibly modulating HDL CEC, including lifestyle modifications, as well as nutraceutical and pharmacological interventions, will be discussed. The objective of this review is to help understanding whether, from the current evidence, HDL CEC may be considered as a valid biomarker of CV risk and a potential pharmacological target for novel therapeutic approaches.

Effects of lipoproteins on endothelial cells and macrophages function and its possible implications on fetal adverse outcomes associated to maternal hypercholesterolemia during pregnancy

Hypercholesterolemia is one of the main risk factors associated with atherosclerosis and cardiovascular disease, the leading cause of death worldwide. During pregnancy, maternal hypercholesterolemia develops, and it can occur in a physiological (MPH) or supraphysiological (MSPH) manner, where MSPH is associated with endothelial dysfunction and early atherosclerotic lesions in the fetoplacental vasculature. In the pathogenesis of atherosclerosis, endothelial activation and endothelial dysfunction, characterized by an imbalance in the bioavailability of nitric oxide, contribute to the early stages of this disease. Macrophages conversion to foam cells, cholesterol efflux from these cells and its differentiation into a pro- or anti-inflammatory phenotype are also important processes that contribute to atherosclerosis. In adults it has been reported that native and modified HDL and LDL play an important role in endothelial and macrophage function. In this review it is proposed that fetal lipoproteins could be also relevant factors involved in the detrimental vascular effects described in MSPH. Changes in the composition and function of neonatal lipoproteins compared to adults has been reported and, although in MSPH pregnancies the fetal lipid profile does not differ from MPH, differences in the lipidomic profiles of umbilical venous blood have been reported, which could have implications in the vascular function. In this review we summarize the available information regarding the effects of lipoproteins on endothelial and macrophage function, emphasizing its possible implications on fetal adverse outcomes associated to maternal hypercholesterolemia during pregnancy.

Plasma concentrations of lipoproteins and risk of lower-limb peripheral artery disease in people with type 2 diabetes: the SURDIAGENE study

AIMS/HYPOTHESIS

The lipid profile has not been fully investigated in individuals with peripheral artery disease (PAD). We aimed to evaluate the relationship between plasma concentrations of lipoproteins and the prevalence of lower-limb PAD at baseline and its incidence during follow-up in people with type 2 diabetes.

METHODS

Plasma concentrations of total cholesterol, HDL-cholesterol, triacylglycerol and apolipoprotein (Apo) A-I, ApoA-II, ApoB-100 and Apo(a) were measured at baseline using colorimetric or MS methods in the SURDIAGENE cohort. Total cholesterol/HDL-cholesterol ratio, non-HDL-cholesterol and LDL-cholesterol were estimated using computation formulas. Logistic and Cox proportional hazard regression models were fitted to estimate OR or HR, with related 95% CI, for baseline prevalence or incidence of major PAD (lower-limb amputation or requirement of revascularisation) during follow-up by increasing lipoprotein tertiles, after adjustment for key confounders.

RESULTS

Among 1468 participants (women 42%, mean ± SD age 65 ± 11 years, duration of diabetes 14 ± 10 years at baseline), 129 (8.8%) had a baseline history of major PAD. Major PAD was less prevalent at baseline in the highest (vs lowest) tertile of HDL-cholesterol (OR 0.42 [95% CI 0.26, 0.71], p = 0.001) and ApoA-I (OR 0.39 [95% CI 0.23, 0.67], p = 0.0007), and more frequent in the highest tertile of total cholesterol/HDL-cholesterol ratio (OR 1.95 [95% CI 1.18, 3.24], p = 0.01). Among 1339 participants without a history of PAD at baseline, incident PAD occurred in 97 (7.2%) during a median (25th-75th percentile) duration of follow-up of 7.1 (4.4-10.7) years, corresponding to 9685 person-years and an incidence rate of 9.8 (95% CI 8.0, 12.0) per 1000 person-years. The risk of incident PAD was lower in the top (vs bottom) tertile of HDL-cholesterol (HR 0.54 [95% CI 0.30, 0.95], p = 0.03) or ApoA-I (HR 0.50 [95% CI 0.28, 0.86], p = 0.01) and higher in the top tertile of total cholesterol/HDL-cholesterol ratio (HR 2.81 [95% CI 1.61, 5.04], p = 0.0002) and non-HDL-cholesterol (HR 1.80 [95% CI 1.06, 3.12], p = 0.03).

CONCLUSIONS/INTERPRETATION

We reported independent associations between HDL-cholesterol, ApoA-I, total cholesterol/HDL-cholesterol ratio or non-HDL-cholesterol and the prevalence or the incidence of major PAD in people with type 2 diabetes. Our findings provide a picture of lipoprotein profile in people with type 2 diabetes. Graphical abstract.

Connection between the Altered HDL Antioxidant and Anti-Inflammatory Properties and the Risk to Develop Alzheimer's Disease: A Narrative Review

The protein composition of high-density lipoprotein (HDL) is extremely fluid. The quantity and quality of protein constituents drive the multiple biological functions of these lipoproteins, which include the ability to contrast atherogenesis, sustained inflammation, and toxic effects of reactive species. Several diseases where inflammation and oxidative stress participate in the pathogenetic process are characterized by perturbation in the HDL proteome. This change inevitably affects the functionality of the lipoprotein. An enlightening example in this frame comes from the literature on Alzheimer's disease (AD). Growing lines of epidemiological evidence suggest that loss of HDL-associated proteins, such as lipoprotein phospholipase A2 (Lp-PLA2), glutathione peroxidase-3 (GPx-3), and paraoxonase-1 and paraoxonase-3 (PON1, PON3), may be a feature of AD, even at the early stage. Moreover, the decrease in these enzymes with antioxidant/defensive action appears to be accompanied by a parallel increase of prooxidant and proinflammatory mediators, in particular myeloperoxidase (MPO) and serum amyloid A (SAA). This type of derangement of balance between two opposite forces makes HDL dysfunctional, i.e., unable to exert its “natural” vasculoprotective property. In this review, we summarized and critically analyzed the most significant findings linking HDL accessory proteins and AD. We also discuss the most convincing hypothesis explaining the mechanism by which an observed systemic occurrence may have repercussions in the brain.

[The Current Significance of Measuring HDL-Cholesterol in Cardiovascular Risk Assessment]

The Current Significance of Measuring HDL-Cholesterol in Cardiovascular Risk Assessment Abstract. In clinical practice, high-density lipoprotein cholesterol (HDL-C) levels are frequently used for cardiovascular risk prediction. HDL particles perform numerous functions that theoretically protect against atherosclerosis. Accordingly, extensive studies have clearly demonstrated that low HDL-C is an important independent risk factor for cardiovascular diseases. However, it is now considered questionable whether very high HDL-C levels are always cardioprotective. This may be explained by the structural heterogeneity of HDL particles and the loss of HDL protective functions in the context of disease, which cannot be detected by the simple measurement of HDL-C. In the future new markers of the functional capacity of HDL particles may replace HDL-C as a traditional parameter for cardiovascular risk assessment.

Mediterranean Diet Decreases the Initiation of Use of Vitamin K Epoxide Reductase Inhibitors and Their Associated Cardiovascular Risk: A Randomized Controlled Trial

Our aim is to assess whether following a Mediterranean Diet (MedDiet) decreases the risk of initiating antithrombotic therapies and the cardiovascular risk associated with its use in older individuals at high cardiovascular risk. We evaluate whether participants of the PREvención con DIeta MEDiterránea (PREDIMED) study allocated to a MedDiet enriched in extra-virgin olive oil or nuts (versus a low-fat control intervention) disclose differences in the risk of initiation of: (1) vitamin K epoxide reductase inhibitors (acenocumarol/warfarin; n = 6772); (2) acetylsalicylic acid as antiplatelet agent (n = 5662); and (3) other antiplatelet drugs (cilostazol/clopidogrel/dipyridamole/ditazol/ticlopidine/triflusal; n = 6768). We also assess whether MedDiet modifies the association between the antithrombotic drug baseline use and incident cardiovascular events. The MedDiet intervention enriched with extra-virgin olive oil decreased the risk of initiating the use of vitamin K epoxide reductase inhibitors relative to control diet (HR: 0.68 [0.46-0.998]). Their use was also more strongly associated with an increased risk of cardiovascular disease in participants not allocated to MedDiet interventions (HRcontrol diet: 4.22 [1.92-9.30], HRMedDiets: 1.71 [0.83-3.52], p-interaction = 0.052). In conclusion, in an older population at high cardiovascular risk, following a MedDiet decreases the initiation of antithrombotic therapies and the risk of suffering major cardiovascular events among users of vitamin K epoxide reductase inhibitors.

Serum amyloid A1 can be a novel biomarker for evaluating the presence and severity of acute coronary syndrome

BACKGROUND

Serum amyloid A (SAA) is an acute phase protein and a novel inflammatory biomarker of cardiovascular diseases. Of the four subtypes, SAA1 is the most representative biomarker. In this study, we aimed to assess the value of SAA1 as a novel biomarker for evaluating the presence and severity of acute coronary syndrome (ACS) in Chinese patients.

METHODS AND RESULTS

A total of 140 ACS patients and 88 non-ACS patients (including 36 stable coronary artery disease (SCAD) patients and 52 healthy controls) who underwent coronary angiography were enrolled. The SAA1 level was significantly higher in ACS patients compared with the SCAD and healthy control subgroups (P < 0.001, respectively), and was significantly higher in the high SYNTAX Score II (SS II) group compared with the medium SS II group and low SS II group (P < 0.001, respectively) in ACS patients. The cutoff level of SAA1 for indicating the presence of ACS was 324.65 ng/mL (sensitivity of 77.9%, specificity of 60.2% and an area under the curve of 0.717). The increased SAA1 levels were positively associated with the presence (OR = 1.013, P < 0.001) and severity (OR = 1.023, P < 0.001) of ACS. Furthermore, there was a positive correlation between SAA1 levels and SS II (r = 0.467, P < 0.001).

CONCLUSIONS

Our results suggest that elevated SAA1 levels may be a novel biomarker for evaluating the presence of ACS and the severity of CAD in ACS patients. Measuring SAA1 levels makes it possible to evaluate the presence of ACS and severity of CAD in ACS patients.

The Alcohol-High-Density Lipoprotein Athero-Protective Axis

Ingestion of alcohol is associated with numerous changes in human energy metabolism, especially that of plasma lipids and lipoproteins. Regular moderate alcohol consumption is associated with reduced atherosclerotic cardiovascular disease (ASCVD), an effect that has been attributed to the concurrent elevations of plasma high-density lipoprotein-cholesterol (HDL-C) concentrations. More recent evidence has accrued against the hypothesis that raising plasma HDL concentrations prevents ASCVD so that other metabolic processes associated with alcohol consumption have been considered. This review explored the roles of other metabolites induced by alcohol consumption-triglyceride-rich lipoproteins, non-esterified free fatty acids, and acetate, the terminal alcohol metabolite in athero-protection: Current evidence suggests that acetate has a key role in athero-protection but additional studies are needed.

High Density Lipoproteins: Metabolism, Function, and Therapeutic Potential

High Density Lipoproteins (HDLs) have long been considered as “good cholesterol,” beneficial to the whole body and, in particular, to cardio-vascular health. However, HDLs are complex particles that undergoes dynamic remodeling through interactions with various enzymes and tissues throughout their life cycle, making the complete understanding of its functions and roles more complicated than initially expected. In this review, we explore the novel understanding of HDLs' behavior in health and disease as a multifaceted class of lipoprotein, with different size subclasses, molecular composition, receptor interactions, and functionality. Further, we report on emergent HDL-based therapeutics tested in small and larger scale clinical trials and their mixed successes.

Effects of Virgin Olive Oil and Phenol-Enriched Virgin Olive Oils on Lipoprotein Atherogenicity

The atherogenicity of low-density lipoprotein (LDL) and triglyceride-rich lipoproteins (TRLs) may be more significant than LDL cholesterol levels. Clinical trials which have led to increased high-density lipoprotein (HDL) cholesterol have not always seen reductions in cardiovascular disease (CVD). Furthermore, genetic variants predisposing individuals to high HDL cholesterol are not associated with a lower risk of suffering a coronary event, and therefore HDL functionality is considered to be the most relevant aspect. Virgin olive oil (VOO) is thought to play a protective role against CVD. This review describes the effects of VOO and phenol-enriched VOOs on lipoprotein atherogenicity and HDL atheroprotective properties. The studies have demonstrated a decrease in LDL atherogenicity and an increase in the HDL-mediated macrophage cholesterol efflux capacity, HDL antioxidant activity, and HDL anti-inflammatory characteristics after various VOO interventions. Moreover, the expression of cholesterol efflux-related genes was enhanced after exposure to phenol-enriched VOOs in both post-prandial and sustained trials. Improvements in HDL antioxidant properties were also observed after VOO and phenol-enriched VOO interventions. Furthermore, some studies have demonstrated improved characteristics of TRL atherogenicity under postprandial conditions after VOO intake. Large-scale, long-term randomized clinical trials, and Mendelian analyses which assess the lipoprotein state and properties, are required to confirm these results.