VLDL Cholesterol Accounts for One-Half of the Risk of Myocardial Infarction Associated With apoB-Containing Lipoproteins.J Am Coll Cardiol. 2020;76:2725-2735. [PMID: 33272366 DOI: 10.1016/j.jacc.2020.09.610]

Excess Apolipoprotein B and Cardiovascular Risk in Women and Men

BACKGROUND

Low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (apoB) are highly correlated measures of atherogenic lipoproteins.

OBJECTIVES

The study investigators hypothesized that excess apoB is associated with an increased risk of myocardial infarction (MI), atherosclerotic cardiovascular disease (ASCVD), and all-cause mortality.

METHODS

The study included 53,484 women and 41,624 men not taking statins from the Copenhagen General Population Study. Associations of excess apoB with the risk of MI, ASCVD, and all-cause mortality were estimated by Cox proportional hazards regressions with 95% CIs. Excess apoB was defined as measured levels of apoB minus expected levels of apoB from LDL-C alone; expected levels were defined by linear regressions of LDL-C levels vs apoB levels in individuals with triglycerides ≤1 mmol/L (89 mg/dL).

RESULTS

During a median follow-up of 9.6 years, 2,048 MIs, 4,282 ASCVD events, and 8,873 deaths occurred. There was a dose-dependent association between excess apoB and the risk of MI and ASCVD in both women and men, as well as an association with the risk of all-cause mortality in women. For ASCVD in women compared with those with excess apoB <11 mg/dL, the multivariable adjusted HR was 1.08 (95% CI: 0.97-1.21) for excess apoB 11 to 25 mg/dL, 1.30 (95% CI: 1.14-1.48) for 26 to 45 mg/dL, 1.34 (95% CI: 1.14-1.58) for 46 to 100 mg/dL, and 1.75 (95% CI: 1.08-2.83) for excess apoB >100 mg/dL. Corresponding HRs in men were 1.14 (95% CI: 1.02-1.26), 1.41 (95% CI: 1.26-1.57), 1.41 (95% CI: 1.25-1.60), and 1.52 (95% CI: 1.13-2.05), respectively. Results were robust across the entire LDL-C spectrum.

CONCLUSIONS

Excess apoB (ie, the value of apoB above that contributed by LDL-C levels alone) is associated dose-dependently with an increased risk of MI and ASCVD in women and men. This finding demonstrates that apoB provides important predictive value beyond LDL-C across the entire LDL-C spectrum.

Blood Lipids, Lipoproteins, and Apolipoproteins With Risk of Coronary Heart Disease: A Prospective Study Among Racially Diverse Populations

BACKGROUND

Comprehensive blood lipoprotein profiles and their association with incident coronary heart disease (CHD) among racially and geographically diverse populations remain understudied.

METHODS AND RESULTS

We conducted nested case-control studies of CHD among 3438 individuals (1719 pairs), including 1084 White Americans (542 pairs), 1244 Black Americans (622 pairs), and 1110 Chinese adults (555 pairs). We examined 36 plasma lipids, lipoproteins, and apolipoproteins, measured by nuclear magnetic resonance spectroscopy, with incident CHD among all participants and subgroups by demographics, lifestyle, and metabolic health status using conditional or unconditional logistic regression adjusted for potential confounders. Conventionally measured blood lipids, that is, total cholesterol, triglycerides, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol, were each associated with incident CHD, with odds ratios (ORs) being 1.33, 1.32, 1.24, and 0.79 per 1-SD increase among all participants. Seventeen lipoprotein biomarkers showed numerically stronger associations than conventional lipids, with ORs per 1-SD among all participants ranging from 1.35 to 1.57 and a negative OR of 0.78 (all false discovery rate <0.05), including apolipoprotein B100 to apolipoprotein A1 ratio (OR, 1.57 [95% CI, 1.45-1.7]), low-density lipoprotein-triglycerides (OR, 1.55 [95% CI, 1.43-1.69]), and apolipoprotein B (OR, 1.49 [95% CI, 1.37-1.62]). All these associations were significant and consistent across racial groups and other subgroups defined by age, sex, smoking, obesity, and metabolic health status, including individuals with normal levels of conventionally measured lipids.

CONCLUSIONS

Our study highlighted several lipoprotein biomarkers, including apolipoprotein B/ apolipoprotein A1 ratio, apolipoprotein B, and low-density lipoprotein-triglycerides, strongly and consistently associated with incident CHD. Our results suggest that comprehensive lipoprotein measures may complement the standard lipid panel to inform CHD risk among diverse populations.

Serum Levels of Adiponectin Are Strongly Associated with Lipoprotein Subclasses in Healthy Volunteers but Not in Patients with Metabolic Syndrome

Metabolic syndrome (MS) is a widespread disease in developed countries, accompanied, among others, by decreased adiponectin serum levels and perturbed lipoprotein metabolism. The associations between the serum levels of adiponectin and lipoproteins have been extensively studied in the past under healthy conditions, yet it remains unexplored whether the observed associations also exist in patients with MS. Therefore, in the present study, we analyzed the serum levels of lipoprotein subclasses using nuclear magnetic resonance spectroscopy and examined their associations with the serum levels of adiponectin in patients with MS in comparison with healthy volunteers (HVs). In the HVs, the serum levels of adiponectin were significantly negatively correlated with the serum levels of large buoyant-, very-low-density lipoprotein, and intermediate-density lipoprotein, as well as small dense low-density lipoprotein (LDL) and significantly positively correlated with large buoyant high-density lipoprotein (HDL). In patients with MS, however, adiponectin was only significantly correlated with the serum levels of phospholipids in total HDL and large buoyant LDL. As revealed through logistic regression and orthogonal partial least-squares discriminant analyses, high adiponectin serum levels were associated with low levels of small dense LDL and high levels of large buoyant HDL in the HVs as well as high levels of large buoyant LDL and total HDL in patients with MS. We conclude that the presence of MS weakens or abolishes the strong associations between adiponectin and the lipoprotein parameters observed in HVs and disturbs the complex interplay between adiponectin and lipoprotein metabolism.

Remnant Cholesterol, Not LDL Cholesterol, Explains Peripheral Artery Disease Risk Conferred by apoB: A Cohort Study

BACKGROUND

Elevated apoB-containing lipoproteins (=remnants+LDLs [low-density lipoproteins]) are a major risk factor for atherosclerotic cardiovascular disease, including peripheral artery disease (PAD) and myocardial infarction. We tested the hypothesis that remnants and LDL both explain part of the increased risk of PAD conferred by elevated apoB-containing lipoproteins. For comparison, we also studied the risk of chronic limb-threatening ischemia and myocardial infarction.

METHODS

apoB, remnant cholesterol, and LDL cholesterol were measured in 93 461 individuals without statin use at baseline from the Copenhagen General Population Study (2003-2015). During up to 15 years of follow-up, 1207 had PAD, 552 had chronic limb-threatening ischemia, and 2022 had myocardial infarction in the Danish National Patient Registry. Remnant and LDL cholesterol were calculated from a standard lipid profile. Remnant and LDL particle counts were additionally measured with nuclear magnetic resonance spectroscopy in 25 347 of the individuals. Results were replicated in 302 167 individuals without statin use from the UK Biobank (2004-2010).

RESULTS

In the Copenhagen General Population Study, multivariable adjusted hazard ratios for risk of PAD per 1 mmol/L (39 mg/dL) increment in remnant and LDL cholesterol were 1.9 (95% CI, 1.5-2.4) and 1.1 (95% CI, 1.0-1.2), respectively; corresponding results in the UK Biobank were 1.7 (95% CI, 1.4-2.1) and 0.9 (95% CI, 0.9-1.0), respectively. In the association from elevated apoB to increased risk of PAD, remnant and LDL cholesterol explained 73% (32%-100%) and 8% (0%-46%), respectively; corresponding results were 63% (30%-100%) and 0% (0%-33%) for risk of chronic limb-threatening ischemia and 41% (27%-55%) and 54% (38%-70%) for risk of myocardial infarction; results for remnant and LDL particle counts corroborated these findings.

CONCLUSIONS

PAD risk conferred by elevated apoB-containing lipoproteins was explained mainly by elevated remnants, while myocardial infarction risk was explained by both elevated remnants and LDL.

ANGPTL3 inhibition, dyslipidemia, and cardiovascular diseases

Optimal management of low-density lipoprotein cholesterol (LDL-C) is a central tenet in the primary and secondary prevention of atherosclerotic cardiovascular disease (ASCVD). However, significant residual cardiovascular risk remains despite achieving guideline-directed LDL-C levels, in part due to mixed hyperlipidemia with elevated fasting and non-fasting triglyceride-rich lipoprotein levels. Advances in human genetics have identified angiopoietin-like 3 (ANGPTL3) as a promising therapeutic target to lower cardiovascular risk. Evidence accrued from genetic epidemiological studies demonstrate that ANGPTL3 loss of function is strongly associated with lowering of circulating LDL-C, triglyceride-rich lipoproteins and concurrent risk reduction in development of coronary artery disease. Pharmacological inhibition of ANGPTL3 with monoclonal antibodies, antisense oligonucleotides and gene editing are in development with early studies showing their safety and efficacy in lowering in both, LDL-C and TGs, circumventing a key limitation of previous therapies. Monoclonal antibodies targeting ANGPTL3 are approved for clinical use in homozygous familial hypercholesteremia in USA and Europe. Although promising, future studies focusing on long-term beneficial effect in reducing cardiovascular events with inhibition of ANGPTL3 are warranted.

The Nutri-Score nutrition label: Associations between the underlying nutritional profile of foods and lipoprotein particle subclass profiles in adults

BACKGROUND AND AIMS

Lipoprotein particle concentrations and size are associated with increased risk for atherosclerosis and premature cardiovascular disease. Certain dietary behaviours may be cardioprotective and public health strategies are needed to guide consumers' dietary choices and help prevent diet-related disease. The Food Standards Agency nutrient profiling system (FSAm-NPS) constitutes the basis of the five-colour front-of-pack Nutri-Score labelling system. No study has examined FSAm-NPS index associations with a wide range of lipoprotein particle subclasses.

METHODS

This was a cross-sectional study of 2006 middle-to older-aged men and women randomly selected from a large primary care centre. Individual participant FSAm-NPS dietary scores were derived from validated food frequency questionnaires. Lipoprotein particle subclass concentrations and size were determined using nuclear magnetic resonance spectroscopy. Multivariate-adjusted linear regression analyses were performed to examine FSAm-NPS relationships with lipoprotein particle subclasses.

RESULTS

In fully adjusted models which accounted for multiple testing, higher FSAm-NPS scores, indicating poorer dietary quality, were positively associated with intermediate-density lipoprotein (β = 0.096, p = 0.005) and small high-density lipoprotein (HDL) (β = 0.492, p = 0.006) concentrations, a lipoprotein insulin resistance score (β = 0.063, p = 0.02), reflecting greater lipoprotein-related insulin resistance, and inversely associated with HDL size (β = -0.030, p = 0.045).

CONCLUSIONS

A higher FSAm-NPS score is associated with a less favourable lipoprotein particle subclass profile in middle-to older-aged adults which may be a potential mechanism underlying reported health benefits of a healthy diet according to Nutri-Score rating.

Increasing the complexity of lipoprotein characterization for cardiovascular risk in type 2 diabetes

The burden of cardiovascular disease is particularly high among individuals with diabetes, even when LDL cholesterol is normal or within the therapeutic target. Despite this, cholesterol accumulates in their arteries, in part, due to persistent atherogenic dyslipidaemia characterized by elevated triglycerides, remnant cholesterol, smaller LDL particles and reduced HDL cholesterol. The causal link between dyslipidaemia and atherosclerosis in T2DM is complex, and our contention is that a deeper understanding of lipoprotein composition and functionality, the vehicle that delivers cholesterol to the artery, will provide insight for improving our understanding of the hidden cardiovascular risk of diabetes. This narrative review covers three levels of complexity in lipoprotein characterization: 1-the information provided by routine clinical biochemistry, 2-advanced nuclear magnetic resonance (NMR)-based lipoprotein profiling and 3-the identification of minor components or physical properties of lipoproteins that can help explain arterial accumulation in individuals with normal LDLc levels, which is typically the case in individuals with T2DM. This document highlights the importance of incorporating these three layers of lipoprotein-related information into population-based studies on ASCVD in T2DM. Such an attempt should inevitably run in parallel with biotechnological solutions that allow large-scale determination of these sets of methodologically diverse parameters.

Hegemony of inflammation in atherosclerosis and coronary artery disease

Inflammation drives coronary artery disease and atherosclerosis implications. Lipoprotein entry, retention, and oxidative modification cause endothelial damage, triggering innate and adaptive immune responses. Recruited immune cells orchestrate the early atherosclerotic lesions by releasing proinflammatory cytokines, expediting the foam cell formation, intraplaque haemorrhage, secretion of matrix-degrading enzymes, and lesion progression, eventually promoting coronary artery syndrome via various inflammatory cascades. In addition, soluble mediators disrupt the dynamic anti- and prothrombotic balance maintained by endothelial cells and pave the way for coronary artery disease such as angina pectoris. Recent studies have established a relationship between elevated levels of inflammatory markers, including C-reactive protein (CRP), interleukins (IL-6, IL-1β), and tumour necrosis factor-alpha (TNF-α) with the severity of CAD and the possibility of future cardiovascular events. High-sensitivity C-reactive protein (hs-CRP) is a marker for assessing systemic inflammation and predicting the risk of developing CAD based on its peak plasma levels. Hence, understanding cross-talk interactions of inflammation, atherogenesis, and CAD is highly warranted to recalculate the risk factors that activate and propagate arterial lesions and devise therapeutic strategies accordingly. Cholesterol-inflammation lowering agents (statins), monoclonal antibodies targeting IL-1 and IL-6 (canakinumab and tocilizumab), disease-modifying antirheumatic drugs (methotrexate), sodium-glucose transport protein-2 (SGLT2) inhibitors, colchicine and xanthene oxidase inhibitor (allopurinol) have shown promising results in reducing inflammation, regressing atherogenic plaque and modifying the course of CAD. Here, we review the complex interplay between inflammatory, endothelial, smooth muscle and foam cells. Moreover, the putative role of inflammation in atherosclerotic CAD, underlying mechanisms and potential therapeutic implications are also discussed herein.

Lipidomics of triglyceride-rich lipoproteins derived from hyperlipidemic patients on inflammation

BACKGROUND AND AIM

Triglyceride-rich lipoproteins (TRLs) can have an important role in atherosclerosis development due to their size and ability to penetrate the endothelium. While high plasma triglyceride (TG) levels and chronic inflammation are relevant in metabolic diseases, it remains unclear whether TGs are atherogenic or which TRL-TG-derived metabolites are responsible for inflammation. Here, we aimed to study the lipidome modifications of TRL particles enriched in TG in patients with hyperlipidemia and their associations with a proinflammatory status both in vivo and in vitro.

METHODS

Using proton nuclear magnetic resonance (1 H-NMR), we analysed the plasma levels of glycoprotein acetyls and the TRL lipidomic profile of 307 patients with dyslipidemia. THP-1-derived macrophages were used as an in vitro model to explore the molecular inflammatory effects mediated by TRL.

RESULTS

In vivo, higher TRL-TG levels were associated with higher circulating levels of NMR-measured glycoproteins (Glyc-A, Glyc-B and Glyc-F; p < .001). Lipidomic analysis showed that TRL-TG enrichment led to decreased cholesterol and phospholipid content (p < .01), an increase in omega-9, and a decrease in saturated fatty acids (p < .001). THP-1 macrophages exposed to increasing TRL particle concentrations augmented the secretion of IL-1β and TNF-α, which varied based on particle composition. Particles with higher cholesterol and phospholipid contents exerted higher cytokine secretion. The activation of MAPK, Akt/NFκB, and caspase-1 was concurrent with this proinflammatory response.

CONCLUSIONS

High TRL-TG levels are associated with a higher systemic inflammatory status and increased particle concentrations. In vitro, higher particle numbers increase proinflammatory cytokine secretion, with cholesterol and phospholipid-rich TRL being more proinflammatory.

Dietary management of dyslipidemia

The rising burden of cardiovascular disease (CVD) has made the achievement of optimal lipoprotein levels a major public health priority. As nearly a fifth of global mortality is associated with dietary factors, and recommendations have been mired in controversy, a fresh look on the available data is attempted. Well established concepts regarding nutrition and cardiometabolic health, role of macronutrients, calories, and controversial foods are discussed followed by recommendations in the Indian context. A healthy dietary pattern rather than individual foods or nutrients is emphasized, and this is generally plant based with optional consumption of dairy, eggs, and meats within the suggested limits. Suggestions/recommendations are given for consumption of individual foods, remembering that choosing appropriate replacement foods is as important as restricting unhealthy foods.

The association of appendicular lean mass and grip strength with low-density lipoprotein, very low-density lipoprotein, and high-density lipoprotein particle diameter: a Mendelian randomization study of the UK Biobank cohort

Aims

Reduced muscle mass and reduced strength are frequently associated with both alterations in blood lipids and poorer cardiometabolic outcomes in epidemiological studies; however, a causal association cannot be determined from such observations. Two-sample Mendelian randomization (MR) was applied to assess the association of genetically determined appendicular lean mass (ALM) and handgrip strength (HGS) with serum lipid particle diameter.

Methods and results

Mendelian randomization was implemented using summary-level data from the largest genome-wide association studies on ALM (n = 450 243), HGS (n = 223 315), and lipoprotein [low-density lipoprotein (LDL), very LDL (VLDL), and high-density lipoprotein (HDL)] particle diameters (n = 115 078). Inverse variance-weighted (IVW) method was used to calculate the causal estimates. Weighted median-based method, MR-Egger, and leave-one-out method were applied as sensitivity analysis. Greater ALM had a statistically significant positive effect on HDL particle diameter (MR-Egger: β = 0.055, SE = 0.031, P = 0.081; IVW: β = 0.068, SE = 0.014, P < 0.001) and a statistically significant negative effect on VLDL particle diameter (MR-Egger: β = -0.114, SE = 0.039, P = 0.003; IVW: β = -0.081, SE = 0.017, P < 0.001). Similarly, greater HGS had a statistically significant positive effect on HDL particle diameter (MR-Egger: β = 0.433, SE = 0.184, P = 0.019; IVW: β = 0.121, SE = 0.052, P = 0.021) and a statistically significant negative effect on VLDL particle diameter (MR-Egger: β = -0.416, SE = 0.163, P = 0.011; IVW: β = -0.122, SE = 0.046, P = 0.009). There was no statistically significant effect of either ALM or HGS on LDL particle diameter.

Conclusion

There were potentially causal associations between both increasing ALM and HGS and increasing HDL particle size and decreasing VLDL particle size. These causal associations may offer possibilities for interventions aimed at improving cardiovascular disease risk profile.

Association between remnant cholesterol and insulin resistance levels in patients with metabolic-associated fatty liver disease

The relationship between remnant cholesterol (RC) and homeostasis model assessment-insulin resistance (HOMA-IR) in the context of metabolic-associated fatty liver disease (MAFLD) remains an area of ambiguity. This investigation was designed to elucidate the potential association between RC and HOMA-IR in a cohort of American adults diagnosed with MAFLD. Data from 5533 participants were procured from the 2017-2018 US National Health and Nutrition Examination (NHANES) databases. A weighted linear regression model was employed to analyze the association between RC and HOMA-IR in the context of MAFLD. Preliminary analysis revealed that 44.67% of the participants were diagnosed with MAFLD, with a higher prevalence observed in individuals aged 50-64 years (31.84%, p < 0.0001) and in males compared to females (53.48% vs. 46.52%, p < 0.0001). A positive correlation was identified between RC and HOMA-IR in MAFLD patients. The threshold effect analysis model indicated a breakpoint at RC = 30 mg/dl, with a more pronounced positive correlation when RC < 30 mg/dl (β = 0.17, p < 0.001). Receiver operating characteristic analysis further demonstrated that among all lipid parameters, RC exhibited the largest area under the curve. The study findings suggest a positive correlation between RC and HOMA-IR in MAFLD patients, indicating that elevated RC may serve as an independent risk factor for MAFLD.

Causal association between lipoproteins and risk of coronary artery disease-a systematic review and meta-analysis of Mendelian randomization studies

OBJECTIVE

To systematically evaluate the causal effect of lipoproteins to the risk of coronary artery disease (CAD) by systematic review and meta-analysis of the associated Mendelian randomization (MR) studies.

METHODS

This systematic review was registered in PROSPERO (ID CRD42023465430). Searches from the databases (e.g., PubMed, Embase, Cochrane, Web of Science) and non-database sources to collect MR studies. The search time frame was from the database inception to August 2023. After data extraction, quality evaluation was performed, and the meta-analysis with bias evaluation was carried out with RevMan software.

RESULTS

A total of 5,828,409 participants from 21 records were included. Quality and bias assessment was performed by evaluating the internal three assumptions of MR studies. Meta-analysis for the causal association between non-HDL lipoproteins and CAD showed a significantly positive association between LDL and CAD (OR 1.37, 95% CI 1.26-1.49; P < 0.001, I2 = 95%), apoB and CAD (OR 1.38, 95% CI 1.11-1.71; P = 0.003, I2 = 98%), and Lp(a) and CAD (OR 1.21, 95% CI 1.12-1.31; P < 0.001, I2 = 99%). Interestingly, although there was no statistical significance in the association between VLDL/apoA1 and CAD (both P > 0.05), the pooled non-HDL lipoproteins showed a significantly positive association with CAD (OR 1.28, 95% CI 1.22-1.34; P < 0.001, I2 = 99%). For the HDL lipoproteins, the pooled OR showed a significantly negative association with CAD (OR 0.84, 95% CI 0.72-0.98; P = 0.002, I2 = 72%). However, the protective effect of HDL on CAD diminished when analyzed together with apoA1 and/or apoB (both P > 0.05). The funnel plot did not show serious publication bias, and sensitivity analysis performed relatively well robustness of the causal association of LDL, apoB, Lp(a), and total cholesterol with CAD.

CONCLUSION

The present meta-analysis suggests an overall effect of causal association between lipoproteins and CAD. Most of the non-HDL lipoproteins (LDL, apoB, Lp(a)) promote CAD, while the protective effect of HDL in CAD still needs to be verified in the future.

Effects of physical activity on the levels of remnant cholesterol: A population-based study

Physical activity (PA) has the potential to bring about favourable changes in plasma lipid profile. However, the relationship between PA and remnant cholesterol (RC) remains unclear. We aimed to study the link between PA and RC using the database of the 2007-2020 National Health and Nutrition Examination Survey (NHANES). PA was categorized based on Physical Activity Guidelines for Americans. A multivariate linear regression model was used to determine the correlations between PA and RC. The study involved a total of 18,396 participants and revealed that individuals whose PA met the guidelines by engaging in moderate-intensity PA at least 150 min per week had lower body mass index and showed decreased levels of triglyceride, TC, and haemoglobin A1c compared to those who were physically inactive, exercising <150 min per week. Participants whose intensity of PA meets PA guidelines had a lower level of RC than those who did not met PA guidelines (β = -1.3, 95% confidence interval [CI]: -1.9 to -0.7, p < 0.001), even after adjusting for confounders. During subgroup analysis, we observed that race (pinteraction  = 0.0089) emerged as a significant factor of interaction.

Unlocking the mysteries of VLDL: exploring its production, intracellular trafficking, and metabolism as therapeutic targets

Reducing circulating lipid levels is the centerpiece of strategies for preventing and treating atherosclerotic cardiovascular disease (ASCVD). Despite many available lipid-lowering medications, a substantial residual cardiovascular risk remains. Current clinical guidelines focus on plasma levels of low-density lipoprotein (LDL). Recent attention has been given to very low-density lipoprotein (VLDL), the precursor to LDL, and its role in the development of coronary atherosclerosis. Preclinical investigations have revealed that interventions targeting VLDL production or promoting VLDL metabolism, independent of the LDL receptor, can potentially decrease cholesterol levels and provide therapeutic benefits. Currently, methods, such as mipomersen, lomitapide, and ANGPTL3 inhibitors, are used to reduce plasma cholesterol and triglyceride levels by regulating the lipidation, secretion, and metabolism of VLDL. Targeting VLDL represents an avenue for new lipid-lowering strategies. Interventions aimed at reducing VLDL production or enhancing VLDL metabolism, independent of the LDL receptor, hold promise for lowering cholesterol levels and providing therapeutic benefits beyond LDL in the management of ASCVD.

Predictive value of ApoB/ApoA-I for recurrence within 1 year after first incident stroke

Background

ApoB/ApoA-I ratio is a reliable indicator of cholesterol balance, particularly in the prediction of ischemic events risk. The aim of this study was to investigate the prognostic value of ApoB/ApoA-I for stroke recurrence within 1 year after the first incident.

Methods

We retrospectively included patients who were first diagnosed with acute (<7 days after onset) ischemic stroke. Blood samples were collected on admission, and serum ApoB and ApoA-I concentrations were measured. We analyzed the relationship between ApoB/ApoA-I ratio and ischemic stroke recurrence within 1 year.

Results

A total of 722 patients with acute ischemic stroke were included, of whom 102 experienced stroke recurrence within 1 year, with a recurrence rate of 14.1%. Serum ApoB/ApoA-I concentrations on admission were higher in patients with stroke recurrence at 1 year compared with those with a good prognosis (P < 0.001). The Kaplan-Meier survival curve revealed a significant difference in cumulative stroke recurrence rates across ApoB/ApoA-I tertiles (log-rank P-value < 0.001). A positive correlation between the ApoB/ApoA-I ratio and the risk of stroke recurrence within 1 year was demonstrated using Cox regression analysis, which remained significant after adjusting for traditional risk factors [hazard ratio (HR) 4.007, 95% confidence interval (CI) 1.661-9.666]. This relationship was particularly strong in patients with LAA stroke (HR 4.955, 95% CI 1.591-15.434). Subgroup analysis further revealed that a high ApoB/ApoA-I ratio was strongly associated with stroke recurrence regardless of whether patients had high or low LDL-C levels.

Discussion

ApoB/ApoA-I ratio, measured during the acute phase of the first stroke, was positively correlated with the risk of stroke recurrence within 1 year.

Association of remnant cholesterol with decreased kidney function or albuminuria: a population-based study in the U.S

BACKGROUND

Dyslipidemia is frequently exhibited in individuals with chronic kidney disease (CKD). Remnant cholesterol (RC), an emerging novel lipid marker, plays an elusive role in CKD progression. This study sought to investigate the association of RC with decreased kidney function or albuminuria in the general population of U.S.

METHOD

Data were retrieved from the continuous 2001 to 2018 cycle of the National Health and Nutrition Examination Survey (NHANES). Individuals aged between 18 and 70 years were included. RC was divided into quartiles. Albuminuria was defined by albumin-to-creatinine ratio (ACR) ≥30 mg/g, while reduced kidney function was described as an estimated glomerular filtration rate (eGFR) below 60 ml/min/1.73 m2. Using a multivariable regression model, the association of RC with decreased eGFR or albuminuria was examined. The dose‒response relationship between RC and eGFR or ACR was also investigated using a restricted cubic spline (RCS) model.

RESULTS

A total of 1551 (10.98%) participants with impaired renal function or albuminuria were identified. After multivariate adjustment, RC was not significantly associated with kidney function decline or albuminuria (odds ratio (OR) 1.24, 95% confidence interval (95% CI): 0.95, 1.61). However, a significantly inverse correlation was observed between RC and eGFR in a dose‒response manner (β -2.12, 95% CI: -3.04, -1.21). This association remained consistent when stratifying data by gender, age, race, hypertension, diabetes and body mass index (BMI).

CONCLUSION

A higher RC was significantly correlated with a lower eGFR in the general population. The role of RC in predicting kidney outcomes needed further investigation in prospective studies.

Performance of the enhanced Sampson-NIH equation for VLDL-C and LDL-C in a population with familial combined hyperlipidemia

INTRODUCTION

Low-density cholesterol (LDL-C) has long been estimated by the Friedewald formula (F-LDL-C); however, this method underestimates LDL-C in patients with hypertriglyceridemia (HTG) or low LDL-C levels. The Martin (M-LDL-C) and Sampson (S-LDL-C) formulas partially resolve these limitations. Recently, Sampson et al. developed a new equation (eS-VLDL-C) that includes ApoB. This new equation could be particularly useful in FCHL, which is characterized by the predominance of triglyceride-rich VLDL and a discordance between LDL-C and ApoB.

METHODS

Very low-density lipoproteins (VLDL-C) was measured in 336 patients with FCHL by sequential ultracentrifugation. LDL-C was estimated by subtracting VLDL-C, estimated by the different equations, from non-HDL cholesterol. Spearman correlations, R2, mean squared error (RMSE), and bias were used to compare the accuracy of the different equations. Concordance of the estimated LDL-C values with LDL-C thresholds and ApoB was also assessed by their kappa coefficients and ROC analysis.

RESULTS

Overall population had a mean age of 47 years, and 61.5% were women. 19.5% had type 2 diabetes, hypertension was present in 20.8%, and only 12.2% were on statin treatment. Both S-LDL-C and eS-LDL-C performed similarly, and better than M-LDL-C and F-LDL-C. In Bland-Altman analysis, eS-LDL-C showed the lowest bias, better performance in HTG, and better concordance with LDL-C treatment goals compared to other formulas (e.g. ρ: 0.87, 95% CI 0.84-0.89).

CONCLUSIONS

LDL-S and LDL-eS equations estimate the concentration of LDL-C with greater accuracy than other formulas. The LDL-eS has best performance in estimating LDL-C with lower RMSE than other formulas.

Cumulative remnant cholesterol predicts cardiovascular outcomes in elderly patients with atherosclerotic cardiovascular disease

AIMS

Remnant cholesterol (RC) reportedly mediates residual cardiovascular risk in atherosclerotic cardiovascular diseases (ASCVD). However, few studies have characterized long-term cumulative RC exposure among elderly people. The study aimed to evaluate the association between cumulative exposure to RC and incident major adverse cardiovascular events (MACE) by analysing a cohort of elderly patients with ASCVD.

METHODS AND RESULTS

This retrospective multicentre cohort study enrolled ASCVD participants aged ≥75 years with baseline visits occurring from 2006 to 2012 followed by four in-person visits. Cumulative RC was estimated as the area under the curve using measurements from the first to fourth visits by using 9-year data. The time-weighted average (TWA) RC was expressed as cumulative exposure to RC averaged by years. All outcomes were follow-up from the fourth visit to the year 2021. Outcomes included a composite of MACE (stroke, unstable angina pectoris, myocardial infarction, and cardiac death). We included 4,680 participants (73.1% male, mean age 79.3 ± 2.5 years). The median follow-up duration was 6.1 years (interquartile range: 3.4-6.6 years). In the multivariable model adjusted for traditional cardiovascular risk factors, low-density lipoprotein cholesterol level, and most recent RC level, the hazard ratios for MACE that compared the high and low tertiles of the RC variables were 1.30 [95% confidence interval (CI), 1.16-1.44] for cumulative RC and 1.36 (95% CI, 1.23-1.52) for TWA RC. Consistent significant associations were observed among most propensity score analyses.

CONCLUSIONS

Long-term cumulative RC was independently associated with incident MACE in elderly participants with ASCVD, suggesting that achieving and maintaining optimal RC levels later in life may still improve cardiovascular outcomes.

Updates in Small Interfering RNA for the Treatment of Dyslipidemias

PURPOSE OF REVIEW

Atherosclerotic cardiovascular disease (ASCVD) is still the leading cause of death worldwide. Despite excellent pharmacological approaches, clinical registries consistently show that many people with dyslipidemia do not achieve optimal management, and many of them are treated with low-intensity lipid-lowering therapies. Beyond the well-known association between low-density lipoprotein cholesterol (LDL-C) and cardiovascular prevention, the atherogenicity of lipoprotein(a) and the impact of triglyceride (TG)-rich lipoproteins cannot be overlooked. Within this landscape, the use of RNA-based therapies can help the treatment of difficult to target lipid disorders.

RECENT FINDINGS

The safety and efficacy of LDL-C lowering with the siRNA inclisiran has been documented in the open-label ORION-3 trial, with a follow-up of 4 years. While the outcome trial is pending, a pooled analysis of ORION-9, ORION-10, and ORION-11 has shown the potential of inclisiran to reduce composite major adverse cardiovascular events. Concerning lipoprotein(a), data of OCEAN(a)-DOSE trial with olpasiran show a dose-dependent drop in lipoprotein(a) levels with an optimal pharmacodynamic profile when administered every 12 weeks. Concerning TG lowering, although ARO-APOC3 and ARO-ANG3 are effective to lower apolipoprotein(apo)C-III and angiopoietin-like 3 (ANGPTL3) levels, these drugs are still in their infancy. In the era moving toward a personalized risk management, the use of siRNA represents a blossoming armamentarium to tackle dyslipidaemias for ASCVD risk reduction.

The Role of Remnant Cholesterol Beyond Low-Density Lipoprotein Cholesterol in Arterial Stiffness: A Cross-Sectional Study

Background: Previous evidence has demonstrated that elevated low-density lipoprotein cholesterol (LDL-C) was associated with atherosclerosis. However, there is scarce population-based evidence for the role of remnant cholesterol (remnant-C) in arterial stiffness, an imaging marker for subclinical atherosclerosis. Herein, we aimed to evaluate the correlation of remnant-C with arterial stiffness beyond LDL-C in a check-up population. Methods: The study included consecutive subjects who visited the Murakami Memorial Hospital for health check-ups between 2004 and 2012. The calculation of remnant-C occurred as total cholesterol minus high-density lipoprotein cholesterol (HDL-C) minus LDL-C. The brachial-ankle pulse wave velocity (baPWV) >1400 cm/sec was defined as arterial stiffness or baPWV abnormality. The independent correlation of remnant-C level to arterial stiffness was evaluated using adjusted regression models. Results: A total of 909 participants were included (mean age 51.1 ± 9.6 years, male sex 64.9%). In multivariate linear regression analyses, remnant-C remained an independent predictor of the baPWV predictor [β: 94.76, 95% confidence interval (CI) 42.19-147.33, P < 0.001] after adjusting for confounders. After multivariable adjustment, including LDL-C, the highest remnant-C quartile odd ratio (OR) (95% CI) was 2.79 (1.27-6.09) for baPWV abnormality compared to the lowest quartile. Furthermore, each 10-mg/dL increase in remnant-C correlated with a 28% increased risk for baPWV abnormality (OR: 1.28, 95% CI: 1.04-1.57). Moreover, the correlation between remnant-C and baPWV abnormality was still significant in the participant subgroup with optimal levels of LDL-C. Conclusions: Our findings demonstrated that remnant-C levels correlated to arterial stiffness with the dependence of LDL-C and other cardiovascular risk factors in a check-up population.

Remnant cholesterol in atherosclerotic cardiovascular disease: A systematic review and meta-analysis

BACKGROUND

Accumulating evidence suggests a substantial contribution of remnant cholesterol (RC) to residual risk for the development or relapse of atherosclerotic cardiovascular disease (ASCVD). We aimed to evaluate the association of RC levels with ASCVD risk by different risk categories and methods of RC assessment. We also assessed available evidence of the effects of lipid-lowering therapies (LLTs) on RC levels.

METHODS

English-language searches of Medline, PubMed, and Embase (inception to 31 January 2023); ClinicalTrials.gov (October 2022); and reference lists of studies and reviews. Studies reporting on the risk of the composite endpoint [all-cause mortality, cardiovascular mortality, and major adverse cardiac events (MACE)] by RC levels were included. Moreover, we searched for studies reporting differences in RC levels after the administration of LLT(s).

RESULTS

Among n = 29 studies with 257,387 participants, we found a pooled linear (pooled HR: 1.27 per 1-SD increase, 95% CI: 1.12-1.43, P < 0.001, I2 = 95%, n = 15 studies) and non-linear association (pooled HR: 1.59 per quartile increase, 95% CI: 1.35-1.85, P < 0.001, I2 = 87.9%, n = 15 studies) of RC levels and the risk of M ACE both in patients with and without established ASCVD. Interestingly, the risk of MACE was higher in studies with directly measured vs. calculated RC levels. In a limited number of studies and participants, LLTs reduced RC levels.

CONCLUSION

RC levels are associated with ASCVD risk both in primary and secondary prevention. Directly measured RC levels are associated with ASCVD risk more evidently. Available LLTs tend to decrease RC levels, although the clinical relevance of RC decrease merits further investigation.

PROSPERO REGISTRATION

CRD42022371346.

Remnant cholesterol, but not low-density lipoprotein cholesterol, is associated with intra-pancreatic fat deposition

AIM

To investigate the associations of components of the lipid panel (and its derivatives) with intra-pancreatic fat deposition (IPFD).

METHODS

All participants underwent abdominal magnetic resonance imaging on the same 3.0-Tesla scanner and IPFD was quantified. Blood samples were collected in the fasted state for analysis of lipid panel components. A series of linear regression analyses was conducted, adjusting for age, sex, ethnicity, body mass index, fasting plasma glucose, homeostatic model assessment of insulin resistance, and liver fat deposition.

RESULTS

A total of 348 participants were included. Remnant cholesterol (P = 0.010) and triglyceride levels (P = 0.008) were positively, and high-density lipoprotein cholesterol level (P = 0.001) was negatively, associated with total IPFD in the most adjusted model. Low-density lipoprotein cholesterol and total cholesterol were not significantly associated with total IPFD. Of the lipid panel components investigated, remnant cholesterol explained the greatest proportion (9.9%) of the variance in total IPFD.

CONCLUSION

Components of the lipid panel have different associations with IPFD. This may open up new opportunities for improving outcomes in people at high risk for cardiovascular diseases (who have normal low-density lipoprotein cholesterol) by reducing IPFD.

Do Triglyceride-Rich Lipoproteins Equal Low-Density Lipoproteins in Risk of ASCVD?

PURPOSE OF REVIEW

Recent large clinical trials have failed to show that triglyceride-rich lipoprotein-lowering therapies decrease the risk of atherosclerotic cardiovascular disease (ASCVD). In this review, we reconcile these findings with evidence showing that elevated levels of triglyceride-rich lipoproteins and the cholesterol they contain, remnant cholesterol, cause ASCVD alongside low-density lipoprotein (LDL) cholesterol.

RECENT FINDINGS

Results from observational epidemiology, genetic epidemiology, and randomized controlled trials indicate that lowering of remnant cholesterol and LDL cholesterol decrease ASCVD risk by a similar magnitude per 1 mmol/L (39 mg/dL) lower non-high-density lipoprotein cholesterol (remnant cholesterol+LDL cholesterol). Indeed, recent guidelines for ASCVD prevention recommend the use of non-high-density lipoprotein cholesterol instead of LDL cholesterol. Current consensus is moving towards recognizing remnant cholesterol and LDL cholesterols as equals per 1 mmol/L (39 mg/dL) higher levels in the risk assessment of ASCVD; hence, triglyceride-rich lipoprotein-lowering therapies should also lower levels of non-HDL cholesterol to reduce ASCVD risk.

Association between Intermediate-Density Lipoprotein Particles and the Progression of Carotid Atherosclerosis: A Community-Based Cohort Study

AIM

Experimental studies report that intermediate-density lipoprotein (IDL), the precursor of low-density lipoprotein, promotes atherosclerotic plaque formation. However, whether IDL is involved in the development of atherosclerosis in humans is still unclear. The aim of this community-based study is to examine the association between IDL particle (IDL-P) concentrations and the 5-year progression of carotid atherosclerosis.

METHODS

Baseline IDL-P concentrations were measured using nuclear magnetic resonance spectroscopy in 927 participants aged 45-74 years with no history of cardiovascular disease (CVD) at baseline. To estimate the association between baseline IDL-P concentrations and 5-year progression of carotid atherosclerosis, indicated by atherosclerotic plaque progression and changes in total plaque area (TPA), multivariable-adjusted regression was employed.

RESULTS

During the 5-year follow-up period, 45.8% of participants developed new plaques. Baseline IDL-P concentrations were significantly associated with the progression of carotid atherosclerosis. Participants in the highest quartile of IDL-P concentrations exhibited 1.36-fold (95% confidence interval [CI]: 1.09-1.68) increased progression of carotid plaque and 1.67-fold (95% CI: 1.04-2.69) higher TPA than those in the lowest quartile. These relationships were independent of baseline concentrations of low-density lipoprotein particles and very-low-density lipoprotein particles and their subclasses.

CONCLUSIONS

Elevated IDL-P concentrations were independently associated with the progression of carotid atherosclerosis, suggesting that IDL-P is a novel risk factor for the development of atherosclerosis.

Triglyceride content increases while cholesterol content decreases in HDL and LDL+IDL fractions following normal meals: The Copenhagen General Population Study of 25,656 individuals

BACKGROUND AND AIMS

During fat tolerance tests, plasma triglycerides increase while high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and intermediate-density lipoprotein (IDL) cholesterol decrease. However, it is unknown whether triglyceride content increases and cholesterol content decreases in HDL and LDL + IDL fractions following normal meals in the general population. Therefore, we tested the hypothesis that triglyceride content increases while cholesterol content decreases in HDL and LDL + IDL fractions following normal meals.

METHODS

In this cross-sectional study, we included 25,656 individuals aged 20-100 years, all without lipid-lowering therapy at examination and selected for metabolomic profiling from the Copenhagen General Population Study. Triglyceride and cholesterol content of 14 lipoprotein fractions weas measured using nuclear magnetic resonance (NMR) spectroscopy. Time since last meal was recorded by the examiner immediately before blood sampling.

RESULTS

Following normal meals in age and sex-adjusted analyses and when compared with fasting levels, plasma triglycerides were higher for up to 5-6 h, and triglyceride content was higher for up to 6-7 h in HDL fractions, for up to 6-7 h in LDL + IDL fractions, and for up to 5-6 h in very-low-density lipoprotein (VLDL) fractions. Further, plasma cholesterol was lower for up to 2-3 h, and cholesterol content was lower for up to 0-1 h in HDL fractions and for up to 4-5 h in LDL + IDL fractions, while cholesterol content was higher for up to 4-5 h in VLDL fractions.

CONCLUSIONS

Following normal meals, triglyceride content increases while cholesterol content decreases in HDL and LDL + IDL fractions.

Triglyceride-Rich Lipoproteins and Remnant Cholesterol in Cardiovascular Disease

Despite the well-established benefits of statin treatments in lowering low-density lipoprotein cholesterol (LDL-C), a significant residual risk for atherosclerotic cardiovascular disease (ASCVD) remains. Triglycerides (TGs) have long been recognized as potential residual risk factors in this context, but recent studies now disclose the substantial role of TG-rich lipoproteins (TRLs) and cholesterol components of metabolized TRLs (commonly referred to as remnant cholesterol) in atherogenesis, not just TGs alone. Evidence derived through diverse sources, including preclinical studies of pathogenic mechanisms, epidemiologic investigations, and genetic research, has consistently supported the considerable contribution of TRLs and remnant cholesterol in predicting occurrences of ASCVD. As emerging biomarkers for predicting atherosclerosis, they have thus become prioritized therapeutic targets, meant to augment LDL-C lowering efforts in individuals at high risk of ASCVD. However, routine clinical testing for remnant cholesterol and TRLs is still in question, necessitating further research into appropriate treatment plans if levels are elevated. New therapies targeting proteins in TG metabolic pathways, particularly angiopoietin-like protein 3 and apolipoprotein C-III, have shown potential advantages in patients with mild-to-moderate hypertriglyceridemia by reducing blood levels of TGs and remnant cholesterol. The aim of this review is to summarize existing evidence linking elevated TRLs and remnant cholesterol with development of ASCVD and to explore additional guidance for clinical therapy.

bubbleHeatmap: an R package for visualization of nightingale health metabolomics datasets

Summary

We present bubbleHeatmap, an R plotting package which combines elements of a bubble plot and heatmap to conveniently display two numerical variables for each data point across a categorical two dimensional grid. This has particular advantages for visualizing the 251 metabolomic measures produced by the automated, high-throughput, 1H-NMR-based platform provided by Nightingale Health, which includes 12 measures repeated across each of 14 lipoprotein subclasses. As these metabolomic profiles are currently available for large biobanks, we provide a figure template to aid the use of bubbleHeatmap in displaying results from analyses using these data.

Availability and implementation

https://cran.r-project.org/web/packages/bubbleHeatmap.

Plasma lipoprotein subclass variation in middle-aged and older adults: Sex-stratified distributions and associations with health status and cardiometabolic risk factors

BACKGROUND

Circulating lipids and lipoproteins mediate cardiovascular risk, however routine plasma lipid biochemistry provides limited information on pro-atherogenic remnant particles.

OBJECTIVE

We analysed plasma lipoprotein subclasses including very low-density and intermediate-density lipoprotein (VLDL and IDL); and assessed their associations with health and cardiometabolic risk.

METHODS

From 1,976 community-dwelling adults aged 45-67 years, 114/1071 women (10.6%) and 153/905 men (16.9%) were categorised as very healthy. Fasting plasma lipoprotein profiles comprising 112 parameters were measured using 1H nuclear magnetic resonance (NMR) spectroscopy, and associations with health status and cardiometabolic risk factors examined.

RESULTS

HDL cholesterol was higher, and IDL and VLDL cholesterol and triglycerides lower, in very healthy women compared to other women, and women compared to men. IDL and VLDL cholesterol and triglyceride were lower in very healthy men compared to other men. HDL cholesterol and apolipoprotein (apo) A-I were inversely, and IDL and VLDL cholesterol, apoB-100, and apoB-100/apoA-I ratio directly associated with body mass index (BMI) in women and men. In women, LDL, IDL and VLDL cholesterol increased with age. Women with diabetes and cardiovascular disease had higher cholesterol, triglycerides, phospholipids and free cholesterol across IDL and VLDL fractions, with similar trends for men with diabetes.

CONCLUSION

Lipoprotein subclasses and density fractions, and their lipid and apolipoprotein constituents, are differentially distributed by sex, health status and BMI. Very healthy women and men are distinguished by favorable lipoprotein profiles, particularly lower concentrations of VLDL and IDL, providing reference intervals for comparison with general populations and adults with cardiometabolic risk factors.

Lipid Metabolism Traits Mediate the Effect of Psoriasis on Myocardial Infarction Risk: A Two-Step Mendelian Randomization Study

Mendelian randomization (MR) analysis was performed to explore the effect of psoriasis on lipid metabolism traits and myocardial infarction (MI) risk and to analyze the proportion of the mediatory effect of lipid metabolism traits. Publicly accessible summary-level data for psoriasis, lipid metabolism traits, and MI were provided by the genome-wide association studies (GWASs) of the FinnGen Biobank, UK Biobank, and CARDIoGRAMplusC4D, respectively. A two-sample MR was carried out to evaluate the association of psoriasis with lipid metabolism traits and MI. Furthermore, the current research focused on determining if the impact of psoriasis on MI is mediated by lipid metabolism traits. The outcomes of the random effect inverse-variance-weighted (IVW) technique indicated a substantial link between genetically predicted psoriasis and a higher risk of low-density lipoprotein (LDL) cholesterol (OR: 1.006, 95% CI: 1.005-1.007, p = 0.024), apolipoprotein B (OR: 1.018, 95% CI: 1.010-1.026, p = 0.015), lipoprotein A (OR: 1.006, 95% CI: 1.002-1.010, p = 0.039), and MI (OR: 1.066, 95% CI: 1.014-1.121, p = 0.012). The percentages of the mediatory effect of LDL cholesterol, apolipoprotein B, and lipoprotein A under psoriasis conditions on MI risk was 7.4%, 10.2%, and 4.1%, respectively. Psoriasis was causally linked to an elevated risk of lipid metabolism levels and MI. This study further demonstrated that LDL cholesterol, apolipoprotein B, and lipoprotein A mediated the effect of psoriasis on MI risk. And timely lipid-lowering treatment should be given to MI patients.

Remnant cholesterol, low-density lipoprotein cholesterol, and incident cardiovascular disease among Koreans: a national population-based study

AIMS

The synergistic association of remnant cholesterol (remnant-C) and low-density lipoprotein cholesterol (LDL-C) levels with incident cardiovascular disease (CVD) in various subgroups of Koreans was investigated.

METHODS AND RESULTS

Using the national health insurance data, we included subjects aged between 40 and 70 years without a history of CVD and at least two health screenings between 2009 and 2011. The subjects were divided into four groups by LDL-C and remnant-C levels. The primary outcome was CVD, which occurred between 2014 and 2017. Among 3 686 034 (45.6% women) subjects, 144 004 cardiovascular events occurred. Individuals in both high LDL-C and high remnant-C [hazard ratio (HR) 1.266, 95% confidence interval (CI) 1.243-1.289; 7.9%], high LDL-C only (HR 1.098, 95% CI 1.083-1.113; 21.2%), and high remnant-C only groups (HR 1.102, 95% CI 1.087-1.118; 19.1%) had higher risks of CVD than those in the reference group (LDL-C < 3.4 mmol/L and remnant-C < 0.8 mmol/L; 51.8%). A continuous and linear increase in CVD risk was found in those with higher remnant-C levels after adjustment for several confounders, including LDL-C levels. The association of remnant-C ≥ 0.8 mmol/L with an increased CVD risk was consistent across various strata.

CONCLUSIONS

Combined high remnant-C and LDL-C levels confer a higher CVD risk than that individually. Elevated remnant-C values independent of LDL-C levels were associated with a risk of incident CVD. Remnant cholesterol levels in addition to LDL-C levels are important considerations in risk stratification for the primary prevention of CVD.

Effect of the Dual Glucose‐Dependent Insulinotropic Peptide/Gulcagon‐like Peptide 1 Receptor Agonist Tirzepatide on Lipid Profile and Waist Circumference: A Systematic Review and Meta‐analysis

PURPOSE

Tirzepatide, a dual glucose-dependent insulinotropic peptide and glucagon-like peptide 1 receptor agonist, has been approved by the US Food and Drug Administration for the treatment of type 2 diabetes. The purpose of this meta-analysis is to evaluate the impact of tirzepatide on lipid profile and waist circumference (WC), both of which are risk factors of cardiovascular diseases.

METHODS

The PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov databases were systematically searched for articles published from database inception to July 31, 2022. This meta-analysis included 7 randomized controlled trials with a minimum duration of 12 weeks that compared tirzepatide with placebo or other antidiabetic medications. The random-effects model was used to estimate mean differences in lipid profile and WC from baseline. The Cochrane risk-of-bias tool for randomized trials, version 2 was used to assess the outcome's risk of bias. We evaluated the evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

FINDINGS

A total of 8 articles from 7 trials with 7151 participants were included. All 3 eligible maintenance doses of tirzepatide (5, 10, and 15 mg once a week) were effective in increasing total cholesterol (TC) (P < 0.05), HDL-C (P < 0.05), VLDL-C (P < 0.01), triglyceride (TG) (P < 0.01), and WC (P < 0.01) changes from baseline compared with control agents including placebo, semaglutide, dulaglutide, and degludec. Although the evidence for VLDL-C and TGs by GRADE were high or moderate, the evidences for TC, HDL-C, and WC were low or moderate. Only 5mg once-weekly tirzepatide (P < 0.05), not 10 or 15 mg, could induce significant alteration in LDL-C before sensitivity analysis. The evidence by GRADE was moderate.

IMPLICATIONS

Tirzepatide had superiority over placebo or other antidiabetic agents in controlling lipid and WC levels. However, the levels of evidence by GRADE varied greatly across different outcome indicators. Limitations of the study include evaluating secondary outcomes of original trials for the meta-analyses, not assessing the effect of baseline lipid-lowering therapy on lipid levels, and not exploring the bias induced by glycemic improvement and weight loss.

Association of Fish Oil Supplementation with Risk of Coronary Heart Disease in Individuals with Diabetes and Prediabetes: A Prospective Study in the UK Biobank

This study aimed to explore the association between habitual intake of fish oil supplementation and the risk of developing CHD in patients with prediabetes and diabetes. Habitual use of fish oil was assessed by repeated questionnaires. Cox proportional hazard models were applied to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). Over a median follow-up of 11.6 years, 4304 and 3294 CHD cases were documented among 47,663 individuals with prediabetes and 22,146 patients with diabetes in the UK Biobank, respectively. After multivariable adjustment, the HRs (95% CI) of CHD were 0.91 (0.85-0.98) and 0.87 (0.80-0.95) for individuals utilizing fish oil supplementation compared with non-users among the participants with prediabetes and diabetes, respectively. Furthermore, we identified an inverse relationship between fish oil use and CHD incidence, which was significantly mediated by serum C-reactive protein (CRP) levels in individuals with prediabetes and by very-low-density lipoprotein cholesterol (VLDL-C) in patients with diabetes at baseline. The inverse associations were consistent in the analyses stratified by potential confounders. In conclusion, the consumption of fish oil supplements was linked to decreased serum CRP and VLDL-C levels and subsequent CHD risk among adults with prediabetes and diabetes. Our findings highlight the important role of the habitual intake of fish oil supplements in preventing CHD in individuals with impaired glucose metabolism.

Triglyceride-rich lipoproteins, remnant-cholesterol, and atherosclerotic cardiovascular disease

PURPOSE OF REVIEW

Despite indisputable role of LDL-C lowering, a considerable residual risk for atherosclerotic cardiovascular disease (ASCVD) persists. The precise mechanism(s) underlying this phenomenon remain unclear. Triglyceride-rich lipoproteins (TRL) appear to be one of the main mediators, based on the genetic and epidemiologic data. However, whether this is caused by direct effects of Triglycerides or other components of TRL remains uncertain. The cholesterol component of TRL remnants (Rem-C) has been proposed as a more pertinent mediator of the increased risk associated with high triglycerides.

RECENT FINDINGS

Several long-term observational studies have shown a significant relationship between Rem-C and ASCVD events, compared with other triglyceride-related parameters. Recent trials have shown that lowering of triglyceride levels by various agents, including fibrates and omega-3 fatty acids, in statin-treated subjects, did not explain the reduction in ASCVD events. In a large clinical trial with pemafibrate, a highly selective PPAR-α agonist, in type 2 diabetes and elevated triglycerides, the reduction in triglycerides was accompanied by a significant increase in LDL-C and Apo-B levels, despite a reduction in Rem-C, and no effect on ASCVD events.

SUMMARY

Elevated Rem-C as a risk determinant, with LDL-C at goal, requires additional studies in clinical trials. Standardization and accuracy of Rem-C assays (calculated versus direct method) is also needed.

Remnant cholesterol and risk of myocardial infarction in patients with coronary artery disease undergoing revascularization

BACKGROUND

Despite substantial reduction in low-density lipoprotein cholesterol (LDL-C), patients develop recurrent cardiovascular events. Remnant cholesterol (RC), the cholesterol content of triglyceride-rich lipoproteins, is a potential contributor to this residual risk.

OBJECTIVES

To investigate the association between RC and risk for myocardial infarction (MI) in patients with coronary artery disease, and examine whether the predictive value of RC is retained beyond non-high-density lipoprotein cholesterol (non-HDL-C).

METHODS

Data on 9451 patients undergoing coronary revascularization in a single center. RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus LDL-C (estimated using Martin-Hopkins equation). Cox-regression models were used to estimate the association between RC and risk for MI. Discordance analyses were performed to examine the correlation between RC and non-HDL-C (or LDL-C) in relation to MI risk.

RESULTS

Mean age was 65±11 years; 67% presented with acute coronary syndrome. During median follow-up of 9.6 years, 1690 patients developed MI. After multivariable adjustment including lipid-lowering therapies and non-HDL-C, RC was associated with higher MI risk: hazard ratio (95% confidence interval): 1.36 (1.20-1.56) and 1.58 (1.35-1.85) in those with RC levels ≥75th (32.6 mg/dL) and ≥90th (41.8 mg/dL) percentile, compared to RC <50th percentile (25.5 mg/dL). When RC and non-HDL-C (or LDL-C) levels were discordant, the level of RC better reflected the risk for MI.

CONCLUSIONS

Elevated RC is a risk factor for MI independent of lipid-lowering therapies and non-HDL-C, providing further support that RC may serve as a residual cardiovascular risk marker and potential treatment target in patients with coronary artery disease.

Glutaminase 1 isoform up-regulation associated with lipid metabolism disorder induced by methyl tertiary-butyl ether in male rats

Methyl tertiary-butyl ether (MTBE) is a new unleaded gasoline additive, which is considered to be associated with abnormal lipid metabolism in many studies, but the metabolic characteristics and mechanism are still unclear. To observe the characteristics of lipid metabolism induced by MTBE and possible pathways, 21 male Wistar rats got intragastric administration for 24 weeks. The serum lipid metabolism indexes and metabolites were analyzed separately by a biochemical analyzer and untargeted metabolomics. And found that serum high-density lipoprotein cholesterol (HDL-C) levels in the exposure group were significantly reduced, and serum very low-density lipoprotein (VLDL) levels were significantly increased. In untargeted metabolomics, 190 differential metabolites were obtained. Among them, 23 metabolites were found to show the same trend in MTBE exposure groups, which might play a key role in systemic energy metabolism. Further metabolic pathways analysis showed that D-Glutamine, D-glutamate metabolism, and the other three pathways were affected by MTBE significantly. Therefore, we evaluated serum glutamine and glutamate levels and found that MTBE exposure significantly reduced glutamine levels and increased glutamate levels in rat serum and L-02 cells. Further, the key regulatory gene of glutamine metabolism, glutaminase 1 isoform (GLS1), was significantly up-regulated in rat liver and L-02 cells exposed to MTBE. While the effect of glutamine and glutamate metabolism induced by MTBE could be weakened by BPTES, an antagonist of GLS1. In conclusion, our results indicated that MTBE exposure could change the level of glutamine metabolism by promoting GLS1 expression and ultimately lead to abnormal lipid metabolism.

Associations between types and sources of dietary carbohydrates and cardiovascular disease risk: a prospective cohort study of UK Biobank participants

BACKGROUND

Recent studies have reported that the associations between dietary carbohydrates and cardiovascular disease (CVD) may depend on the quality, rather than the quantity, of carbohydrates consumed. This study aimed to assess the associations between types and sources of dietary carbohydrates and CVD incidence. A secondary aim was to examine the associations of carbohydrate intakes with triglycerides within lipoprotein subclasses.

METHODS

A total of 110,497 UK Biobank participants with ≥ two (maximum five) 24-h dietary assessments who were free from CVD and diabetes at baseline were included. Multivariable-adjusted Cox regressions were used to estimate risks of incident total CVD (4188 cases), ischaemic heart disease (IHD; 3138) and stroke (1124) by carbohydrate intakes over a median follow-up time of 9.4 years, and the effect of modelled dietary substitutions. The associations of carbohydrate intakes with plasma triglycerides within lipoprotein subclasses as measured by nuclear magnetic resonance (NMR) spectroscopy were examined in 26,095 participants with baseline NMR spectroscopy measurements.

RESULTS

Total carbohydrate intake was not associated with CVD outcomes. Free sugar intake was positively associated with total CVD (HR; 95% CI per 5% of energy, 1.07;1.03-1.10), IHD (1.06;1.02-1.10), and stroke (1.10;1.04-1.17). Fibre intake was inversely associated with total CVD (HR; 95% CI per 5 g/d, 0.96;0.93-0.99). Modelled isoenergetic substitution of 5% of energy from refined grain starch with wholegrain starch was inversely associated with total CVD (0.94;0.91-0.98) and IHD (0.94;0.90-0.98), and substitution of free sugars with non-free sugars was inversely associated with total CVD (0.95;0.92-0.98) and stroke (0.91;0.86-0.97). Free sugar intake was positively associated with triglycerides within all lipoproteins.

CONCLUSIONS

Higher free sugar intake was associated with higher CVD incidence and higher triglyceride concentrations within all lipoproteins. Higher fibre intake and replacement of refined grain starch and free sugars with wholegrain starch and non-free sugars, respectively, may be protective for incident CVD.

Omega-3 Fatty Acids in Cardiovascular Disease and Diabetes: a Review of Recent Evidence

PURPOSE OF REVIEW

Omega-3 fatty acids (n-3 FA) lower triglycerides, have anti-inflammatory properties, and improve metabolism. Clinical evidence of cardiovascular benefit with omega-3 fatty acids is mixed. We discuss mechanisms providing biological plausibility of benefit of omega-3 fatty acids in cardiovascular risk reduction and review clinical trials investigating the benefits of prescription omega-3 fatty acids in dyslipidemia, atherosclerotic cardiovascular disease (ASCVD), and diabetes.

RECENT FINDINGS

Although early trials showed no benefit of omega-3 fatty acids in ASCVD, the REDUCE-IT trial noted significant risk reduction in ASCVD events with highly purified EPA (icosapent ethyl) use which has changed the landscape for currently available therapeutic options. However, other large trials like STRENGTH and VITAL, which used different formulations of prescription omega-3 fatty acids, did not note significant cardiovascular risk reduction. Thus the effectiveness of omega-3 fatty acids for cardiovascular disease prevention is an ongoing topic of debate. A relative paucity of studies examining benefits for glycemic outcomes in persons with diabetes exists; however, few studies have suggested lack of benefit to date. Significant residual cardiovascular risk exists for individuals with hypertriglyceridemia. Prescription omega-3 fatty acids are more commonly used for CV risk reduction in these patients. Clinical guideline statements now recommend icosapent ethyl use for selected individuals with hypertriglyceridemia to reduce cardiovascular events given recent evidence from the REDUCE-IT trial. Nonetheless, data from other large scale trials has been mixed, and future research is needed to better understand how different preparations of omega-3 may differ in their cardiovascular and metabolic effects, and the mechanisms for their benefit.

PCSK9 Inhibitors Have Apolipoprotein C-III-Related Anti-Inflammatory Activity, Assessed by 1H-NMR Glycoprotein Profile in Subjects at High or very High Cardiovascular Risk

Atherosclerosis is a chronic inflammatory disease caused by the accumulation of cholesterol in the intima. Proprotein convertase subtilisin/kexin type 9 inhibitors (iPCSK9) can reduce low-density lipoprotein (LDL) cholesterol levels by 60%, but there is still no evidence that they can lower markers of systemic inflammation such as high-sensitivity C-reactive protein (hsCRP). Acute-phase serum glycoproteins are upregulated in the liver during systemic inflammation, and their role as inflammatory biomarkers is under clinical evaluation. In this observational study, we evaluate the effects of iPCSK9 on glycoproteins (Glyc) A, B and F. Thirty-nine patients eligible for iPCSK9 therapy were enrolled. One sample before and after one to six months of iPCSK9 therapy with alirocumab was obtained from each patient. Lipids, apolipoproteins, hsCRP and PCSK9 levels were measured by biochemical analyses, and the lipoprotein and glycoprotein profiles were measured by 1H nuclear magnetic resonance (1H-NMR). The PCSK9 inhibitor reduced total (36.27%, p < 0.001), LDL (55.05%, p < 0.001) and non-high-density lipoprotein (HDL) (45.11%, p < 0.001) cholesterol, apolipoprotein (apo) C-III (10%, p < 0.001), triglycerides (9.92%, p < 0.001) and glycoprotein signals GlycA (11.97%, p < 0.001), GlycB (3.83%, p = 0.017) and GlycF (7.26%, p < 0.001). It also increased apoA-I (2.05%, p = 0.043) and HDL cholesterol levels (11.58%, p < 0.001). Circulating PCSK9 levels increased six-fold (626.28%, p < 0.001). The decrease in Glyc signals positively correlated with the decrease in triglycerides and apoC-III. In conclusion, in addition to LDL cholesterol, iPCSK9 therapy also induces a reduction in systemic inflammation measured by 1H-NMR glycoprotein signals, which correlates with a decrease in triglycerides and apoC-III.

Elevated remnant cholesterol, plasma triglycerides, and cardiovascular and non-cardiovascular mortality

AIMS

Cholesterol carried in triglyceride-rich lipoproteins, also called remnant cholesterol, is being increasingly acknowledged as an important causal risk factor for atherosclerosis. Elevated remnant cholesterol, marked by elevated plasma triglycerides, is associated causally with an increased risk of atherosclerotic cardiovascular disease. The association with cause-specific mortality is, however, unclear. The aim of this study was to test the hypothesis that elevated remnant cholesterol and plasma triglycerides are associated with increased mortality from cardiovascular disease, cancer, and other causes.

METHODS AND RESULTS

Using a contemporary population-based cohort, 87 192 individuals from the Copenhagen General Population Study aged 20-69 years at baseline in 2003-2015 were included. During up to 13 years of follow-up, 687 individuals died from cardiovascular disease, 1594 from cancer, and 856 from other causes, according to the National Danish Causes of Death Registry. In individuals with remnant cholesterol ≥1.0 mmol/L (≥39 mg/dL; 22% of the population) compared with those with levels <0.5 mmol/L (<19 mg/dL), multivariable-adjusted mortality hazard ratios were 2.2 (95% confidence interval 1.3-3.5) for cardiovascular disease, 1.0 (0.7-1.3) for cancer, and 2.1 (1.4-3.3) for other causes. Exploratory analysis of the cause of death subcategories showed corresponding hazard ratios of 4.4 (1.6-11) for ischemic heart disease, 8.4 (2.0-34) for infectious diseases, and 9.1 (1.9-43) for endocrinological diseases. Results for plasma triglycerides >2 vs. <1 mmol/L (>177 vs. <89 mg/dL) were similar.

CONCLUSION

Remnant cholesterol of ≥1 mmol/L (39 mg/dL), present in 22% of the population, and plasma triglycerides of ≥2 mmol/L (177 mg/dL), present in 28% of the population, were associated with two-fold mortality from cardiovascular and other causes, but not from cancer. This novel finding should be confirmed in other cohorts.

Interplay of Atherogenic Particle Number and Particle Size and the Risk of Coronary Heart Disease

BACKGROUND

We examined the interplay of apolipoprotein B (apoB) and LDL particle size, approximated by the LDL-cholesterol (LDL-C)/apoB ratio, on the risk of new-onset coronary heart disease (CHD).

METHODS

Participants without cardiovascular disease from the UK Biobank (UKB; n = 308 182), the Women's Health Study (WHS; n = 26 204), and the Framingham Heart Study (FHS; n = 2839) were included. Multivariable Cox models were used to assess the relationship between apoB and LDL-C/apoB ratio and incidence of CHD (14 994 events). Our analyses were adjusted for age, sex (except WHS), HDL-cholesterol (HDL-C), systolic blood pressure, antihypertensive treatment, diabetes, and smoking.

RESULTS

In all 3 studies, there was a strong positive correlation between apoB and LDL-C (correlation coefficients r = 0.80 or higher) and a weak inverse correlation of apoB with LDL-C/apoB ratio (-0.28 ≤ r ≤ -0.14). For all 3 cohorts, CHD risk was higher for higher levels of apoB. Upon multivariable adjustment, the association between apoB and new-onset CHD remained robust and statistically significant in all 3 cohorts with hazard ratios per 1 SD (95% CI): 1.24 (1.22-1.27), 1.33 (1.20-1.47), and 1.24 (1.09-1.42) for UKB, WHS, and FHS, respectively. However, the association between LDL-C/apoB and CHD was statistically significant only in the FHS cohort: 0.78 (0.64-0.94).

CONCLUSIONS

Our analysis confirms that apoB is a strong risk factor for CHD. However, given the null association in 2 of the 3 studies, we cannot confirm that cholesterol-depleted LDL particles are substantially more atherogenic than cholesterol-replete particles. These results lend further support to routine measurement of apoB in clinical care.

Plant-Based Diets and Lipid, Lipoprotein, and Inflammatory Biomarkers of Cardiovascular Disease: A Review of Observational and Interventional Studies

Plant-based diets (PBDs) are becoming increasingly popular. Thus far, the literature has focused on their association with lipid profiles, with less investigation of lipoprotein and inflammatory profiles. Because pro-atherogenic lipid, lipoprotein, and inflammatory processes may facilitate the development of atherosclerosis, understanding the relation between PBDs and these processes is important to inform risk mitigation strategies. Therefore, the objective of this paper was to review the literature on PBDs and lipid, lipoprotein, and inflammatory biomarkers of cardiovascular disease (CVD). A structured literature search was performed, retrieving 752 records, of which 43 articles were included. Plant-based diets generally associated with favourable lipid and lipoprotein profiles, characterised by decreased total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B concentrations, and less low-grade inflammation, characterised by decreased C-reactive protein concentrations. Effect sizes from PBD interventions were greatest compared to habitual dietary patterns, and for non-low-fat vegan and tightly controlled dietary interventions. Associations between PBD indices and the reviewed biomarkers were less consistent. Findings are discussed with reference to the literature on PBDs and PBD indices and CVD risk, the associations between specific plant food groups and CVD outcomes and the reviewed biomarker outcomes, and the potential mechanisms underpinning associations between PBDs and reduced CVD risk.

Cholesterol Content of Very-Low-Density Lipoproteins Is Associated with 1-Year Mortality in Acute Heart Failure Patients

Considering the relationship between the extent of metabolic derangement and the disease severity in heart failure, we hypothesized that the lipid content of very-low-density lipoprotein (VLDL) may have prognostic value for 1 year mortality in acute heart failure (AHF). Baseline serum levels of VLDL cholesterol (VLDL-C), VLDL triglycerides (VLDL-TG), VLDL phospholipids (VLDL-PL), and VLDL apolipoprotein B (VLDL-apoB) were measured using NMR spectroscopy. We calculated the ratios of the respective VLDL lipids and VLDL apoB (VLDL-C/VLDL-apoB, VLDL-TG/VLDL-apoB, and VLDL-PL/VLDL-apoB), as estimators of the cholesterol, triglyceride, and phospholipid content of VLDL particles and tested their association with mortality. Out of 315 AHF patients, 118 (37.5%) patients died within 1 year after hospitalization for AHF. Univariable Cox regression analyses revealed a significant inverse association of VLDL-C/VLDL-apoB (hazard ratio (HR) 0.43, 95% confidence interval (CI) 0.29−0.64, p < 0.001), VLDL-TG/VLDL-apoB (HR 0.79, 95% CI 0.71−0.88, p < 0.001), and VLDL-PL/VLDL-apoB (HR 0.37, 95% CI 0.25−0.56, p < 0.001) with 1 year mortality. Of the tested parameters, only VLDL-C/VLDL-apoB remained significant after adjustment for age and sex, as well as other clinical and laboratory parameters that showed a significant association with 1 year mortality in the univariable analyses. We conclude that cholesterol content of circulating VLDL (VLDL-C/VLDL-apoB) might be of prognostic value in AHF.

Effects of general and central adiposity on circulating lipoprotein, lipid, and metabolite levels in UK Biobank: A multivariable Mendelian randomization study

Background

The direct effects of general adiposity (body mass index (BMI)) and central adiposity (waist-to-hip-ratio (WHR)) on circulating lipoproteins, lipids, and metabolites are unknown.

Methods

We used new metabolic data from UK Biobank (N=109,532, a five-fold higher N over previous studies). EDTA-plasma was used to quantify 249 traits with nuclear-magnetic-resonance spectroscopy including subclass-specific lipoprotein concentrations and lipid content, plus pre-glycemic and inflammatory metabolites. We used univariable and multivariable two-stage least-squares regression models with genetic risk scores for BMI and WHR as instruments to estimate total (unadjusted) and direct (mutually-adjusted) effects of BMI and WHR on metabolic traits; plus effects on statin use and interaction by sex, statin use, and age (proxy for medication use).

Findings

Higher BMI decreased apolipoprotein B and low-density lipoprotein cholesterol (LDL-C) before and after WHR-adjustment, whilst BMI increased triglycerides only before WHR-adjustment. These effects of WHR were larger and BMI-independent. Direct effects differed markedly by sex, e.g., triglycerides increased only with BMI among men, and only with WHR among women. Adiposity measures increased statin use and showed metabolic effects which differed by statin use and age. Among the youngest (38-53y, statins-5%), BMI and WHR (per-SD) increased LDL-C (total effects: 0.04-SD, 95%CI=-0.01,0.08 and 0.10-SD, 95%CI=0.02,0.17 respectively), but only WHR directly. Among the oldest (63-73y, statins-29%), BMI and WHR directly lowered LDL-C (-0.19-SD, 95%CI=-0.27,-0.11 and -0.05-SD, 95%CI=-0.16,0.06 respectively).

Interpretation

Excess adiposity likely raises atherogenic lipid and metabolite levels exclusively via adiposity stored centrally, particularly among women. Apparent effects of adiposity on lowering LDL-C are likely explained by an effect of adiposity on statin use.

Funding

UK Medical Research Council; British Heart Foundation; Novo Nordisk; National Institute for Health Research; Wellcome Trust; Cancer Research UK.

Xin-Ji-Er-Kang protects heart from ischemia-reperfusion injury by rebalancing lipid metabolism

Background and Purpose: We have previously reported a cardioprotective effect with Xin-Ji-Er-Kang (XJEK) treatment in mice with myocardial infarction (MI)-induced heart failure, but no report about its potential functions in myocardial ischemia-reperfusion (MIR) injury. Here we studied the therapeutic effects of XJEK on MIR injury and investigated the mechanisms involved.

Experimental Approach: MIR model of Balb/c mice induced by left anterior descending coronary artery ligation for half an hour, followed by reperfusion, was utilized to study the potential therapeutic effects of XJEK on MIR-induced cardiac injury. Ultra-performance liquid chromatography tandem Orbitrap mass spectrometry platform was used for studying serum lipid metabolic signatures.

Key Results: MIR caused cardiac dysfunctions, cardiac injury, myocardial fibrosis, and increased inflammation, and all the observed abnormalities caused by MIR were largely corrected by XJEK treatment. Mechanistically, XJEK exerts its cardioprotective effect in the context of MIR injury by suppressing MIR-induced inflammation and dysregulation of serum lipid metabolism.

Conclusion and Implications: We have demonstrated for the first time that XJEK protects heart from MIR injury by restoring dysregulated lipidomics. Our data provide new evidence to support a therapeutic effect for XIEK on MIR-induced cardiac injury, and pave the way for exploring the therapeutic potential of XJEK in large animal study and early clinical trial.

Association of lipid profile with obesity among breast cancer survivors: a cross-sectional study

Background

The role of lipid metabolism in obesity and cancer manifestations cannot be underestimated, but whether alterations in lipid metabolism can manipulate the vasculature to promote obesity among breast cancer (BC) survivors is yet to be clearly understood. This study quantified plasma lipid and particle sizes using high-throughput proton (¹H) nuclear magnetic resonance (NMR) and tested their associations with obesity among breast cancer (BC) survivors.

Methods

A total of 348 (225 premenopausal and 123 postmenopausal) BC survivors enrolled from five hospitals in Korea were included. We assessed thirty-four plasma lipid biomarkers using ¹H NMR, and obesity status was defined as a body mass index (BMI) of 25 kg/m² or greater. Generalized linear and logistic regression models were applied to estimate the least-square means of BMI (kg/m²) and odds ratio (OR)s of obesity, respectively, and the corresponding 95% confidence interval (CI)s across plasma lipid levels.

Results

Mean (SD) values of BMI was 23.3 (3.2) kg/m² and 90 (25.9%) had BMI of ≥ 25 kg/m². BMI levels increased with increasing total triglycerides (TG), TG in lipoproteins and very-low-density lipoprotein (VLDL) subfractions. However, BMI levels decreased with increasing tertiles of high-density lipoprotein (HDL)-cholesterol (C) and HDL particle size (HDL-p). Similar associations were observed in the logistic regression models. The increasing and decreasing BMI trends with TG and HDL profiles respectively were predominantly limited to premenopausal BC survivors.

Conclusions

Increasing levels of plasma total TG and TG in lipoproteins were associated with increasing levels of BMI among premenopausal BC survivors. High HDL-C levels and large HDL-p were inversely associated with obesity among premenopausal BC survivors. Due to the cross-sectional design of this study, longitudinal studies are necessary to examine the association between obesity and lipid profile among BC survivors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01674-2.

Comprehensive proteomic analysis to elucidate the anti-heat stress effects of nano-selenium in rainbow trout (Oncorhynchus mykiss)

Because of the continuous intensification of global warming, extreme climate fluctuations, and high-density farming, cold-water rainbow trout (Oncorhynchus mykiss) are exposed to conditions of heat stress, which has severely impacted their survival and yield. Nano-selenium (nano-Se) shows higher biological activity and lower toxicity and has emerged as an ideal and ecological Se formulation. Herein rainbow trout were fed either a basal diet (control group) or basal diet plus 5 mg/kg nano-Se (treatment group). Samples were collected before (18 °C for 9 days; CG18, Se18) and after (24 °C for 8 h; CG24, Se24) heat stress. The DIA/SWATH approach was then applied to compare changes at the proteome level. We found 223 and 269 differentially abundant proteins in the CG18-CG24 and Se18-Se24 groups, respectively, which mainly included apoptosis-, heat stress-, and lipid-related proteins. In comparison with the CG18-CG24 group, the Se18-Se24 group showed higher abundance of molecular chaperone, such as Hsp70, Hsp90a.1, Hspa8, Hsp30, DNAJA4, Dnajb1, Bag2 and Ahsa1; on nano-Se supplementation, the heat stress-induced decline in the abundance of the selenoprotein MsrB2 was partially restored. Furthermore, nano-Se supplementation downregulated the abundance of lipid-related (CYP51, EBP, DHCR7, DHCR24, and APOB) and pro-apoptotic (caspase-8 and Bad) proteins. Protein-protein interaction analyses suggested that nano-Se inhibits apoptosis by upregulating the expression of Hsp70, Hsp90a.1, Hspa8, and Dnajb1; further, Hsp70/Hspa8 and MsrB2 appear to play a synergistic role in antioxidant defense under heat stress. Overall, our findings provide novel insights into nano-Se-mediated tolerance of heat stress, demonstrating that nano-Se exerts its anti-heat stress effects in rainbow trout by promoting protein repair, enhancing recovery of antioxidant enzyme activity, and alleviating lipid metabolism and apoptosis.

Diagnosis of remnant hyperlipidaemia

PURPOSE OF REVIEW

In recent years, there has been interest for the development of simplified diagnosis algorithms of dysbetalipoproteinemia (DBL) in order to avoid the complex testing associated with the Fredrickson criteria (reference method). The purpose of this review is to present recent advances in the field of DBL with a focus on screening and diagnosis.

RECENT FINDINGS

Recently, two different multi-step algorithms for the diagnosis of DBL have been published and their performance has been compared to the Fredrickson criteria. Furthermore, a recent large study demonstrated that only a minority (38%) of DBL patients are carriers of the E2/E2 genotype and that these individuals presented a more severe phenotype.

SUMMARY

The current literature supports the fact that the DBL phenotype is more heterogeneous and complex than previously thought. Indeed, DBL patients can present with either mild or more severe phenotypes that can be distinguished as multifactorial remnant cholesterol disease and genetic apolipoprotein B deficiency. Measurement of apolipoprotein B as well as APOE gene testing are both essential elements in the diagnosis of DBL.

Bmal1 regulates production of larger lipoproteins by modulating cAMP-responsive element-binding protein H and apolipoprotein AIV

BACKGROUND AND AIMS

High plasma lipid/lipoprotein levels are risk factors for various metabolic diseases. We previously showed that circadian rhythms regulate plasma lipids and deregulation of these rhythms causes hyperlipidemia and atherosclerosis in mice. Here, we show that global and liver-specific brain and muscle aryl hydrocarbon receptor nuclear translocator-like 1 (Bmal1)-deficient mice maintained on a chow or Western diet developed hyperlipidemia, denoted by the presence of higher amounts of triglyceride-rich and apolipoprotein AIV (ApoAIV)-rich larger chylomicron and VLDL due to overproduction.

APPROACH AND RESULTS

Bmal1 deficiency decreased small heterodimer partner (Shp) and increased microsomal triglyceride transfer protein (MTP), a key protein that facilitates primordial lipoprotein assembly and secretion. Moreover, we show that Bmal1 regulates cAMP-responsive element-binding protein H (Crebh) to modulate ApoAIV expression and the assembly of larger lipoproteins. This is supported by the observation that Crebh-deficient and ApoAIV-deficient mice, along with Bmal1-deficient mice with knockdown of Crebh, had smaller lipoproteins. Further, overexpression of Bmal1 in Crebh-deficient mice had no effect on ApoAIV expression and lipoprotein size.

CONCLUSIONS

These studies indicate that regulation of ApoAIV and assembly of larger lipoproteins by Bmal1 requires Crebh. Mechanistic studies showed that Bmal1 regulates Crebh expression by two mechanisms. First, Bmal1 interacts with the Crebh promoter to control circadian regulation. Second, Bmal1 increases Rev-erbα expression, and nuclear receptor subfamily 1 group D member 1 (Nr1D1, Rev-erbα) interacts with the Crebh promoter to repress expression. In short, Bmal1 modulates both the synthesis of primordial lipoproteins and their subsequent expansion into larger lipoproteins by regulating two different proteins, MTP and ApoAIV, through two different transcription factors, Shp and Crebh. It is likely that disruptions in circadian mechanisms contribute to hyperlipidemia and that avoiding disruptions in circadian rhythms may limit/prevent hyperlipidemia and atherosclerosis.

ANGPTL3 Is Involved in the Post-prandial Response in Triglyceride-Rich Lipoproteins and HDL Components in Patients With Coronary Artery Disease

It is well-established that there exists an inverse relationship between high-density lipoprotein (HDL) cholesterol and triglyceride (TG) levels in the plasma. However, information is lacking on the impact of post-prandial triglyceride-rich lipoproteins (TRLs) on the structure of HDL subclasses in patients with coronary artery disease (CAD). In this study, the data of 49 patients with CAD were analyzed to evaluate dynamic alterations in post-prandial lipid profiles using nuclear magnetic resonance-based methods. An enzyme-linked immunosorbent assay was used to quantify the serum angiopoietin-like protein 3 (ANGPTL3). After glucose supplementation, the expression of hepatic ANGPTL3 was evaluated both in vitro and in vivo. Compared to fasting levels, the post-prandial serum TG level of all participants was considerably increased. Although post-prandial total cholesterol in HDL (HDL-C) remained unchanged, free cholesterol in HDL particles (HDL-FC) was significantly reduced after a meal. Furthermore, the post-prandial decrease in the HDL-FC level corresponded to the increase in remnant cholesterol (RC), indicating the possible exchange of free cholesterol between HDL and TRLs after a meal. Moreover, CAD patients with exaggerated TG response to diet, defined as TG increase >30%, tend to have a greater post-prandial increase of RC and decrease of HDL-FC compared to those with TG increase ≤30%. Mechanistically, the fasting and post-prandial serum ANGPTL3 levels were significantly lower in those with TG increase ≤30% than those with TG increase >30%, suggesting that ANGPTL3, the key lipolysis regulator, may be responsible for the different post-prandial responses of TG, RC, and HDL-FC.