Atherogenic Low-density Lipoprotein Research Articles

Atherogenic low-density lipoprotein and cardiovascular risk.

Despite reductions in low-density lipoprotein (LDL) cholesterol (LDLc), residual cardiovascular risk remains due to factors beyond lipoprotein levels, such as LDL particle count, size, electronegativity and modifications. Technological advances allow detailed profiling of LDL particles, offering potential biomarkers for diagnosis, prognosis, and treatment of cardiovascular disease (CVD). The aim of this review is to provide an updated overview of the state of knowledge in the field of LDL atherosclerotic role, which is evolving rapidly due to technological advances in biomarker measurement and applications. While small dense LDL has been linked to increased CVD risk, current approaches favor a comprehensive evaluation of all lipoprotein subtypes, as this is a more feasible and standardized method. The atherogenic potential of circulating oxidized LDL (oxLDL) may be the key factor in the onset and progression of atherosclerosis. Thus, elevated oxLDL levels are recognized as a marker of increased CVD risk in both general and high-risk populations, although further research is needed to clarify some conflicting findings. The oxidized LDL receptor 1 (LOX-1) has emerged as a promising target for immunotherapy and innovative drug delivery strategies to modulate atherosclerosis. A panel of biomarkers related to LDL atherogenicity may help predict future ischemic events. An atheroprotective diet and increased physical activity could improve LDL oxidation. OxLDL has become a target for immunomodulatory antiatherosclerosis therapy and delivering LDL-based nanocarriers holds promise for both imaging and therapeutics.

Combination therapy with GalNAc-siRNA drugs targeting both PCSK9 and APOC3 resulted in enhanced lipid lowering in mice

Abstract Introduction Aggressive lowering of both atherogenic low-density lipoprotein cholesterol (LDL-C) and triglyceride-rich lipoproteins (TRLs) could reduce residual atherosclerotic cardiovascular disease (ASCVD) risk. Drugs targeting PCSK9 or APOC3 have shown good lipid-lowering effects in clinic. Here, we have developed GalNAc-conjugated siRNAs, RBD7022 targeting PCSK9 and RBD5044 targeting APOC3, as novel therapeutic agents to lower LDL-C and triglyceride (TG) plasma levels respectively. Each drug shows potent and durable effect in silencing its own target. However, it is unknown whether the combined therapy with siRNA drugs targeting both PCSK9 and APOC3 will generate enhanced effects in lipid lowering. Purpose To investigate the effects of fixed-dose combination of RBD7022 and RBD5044 on LDL-C, TG and total cholesterol (TC). Methods RBD7022 and RBD5044 completely match the human PCSK9 and APOC3 transcripts respectively. RBD7022 has 2 nucleotide mismatches with mouse pcsk9, but still shows silencing activity in mice, while RBD5044 has no activity due to 5 mismatches with mouse apoc3. Therefore, humanized APOC3 transgenic mice were used in this study, which had serious hypertriglyceridemia with relatively high cholesterol and TG levels. They were randomized into 8 groups with treatment of RBD7022 (1 mg/kg or 3 mg/kg), RBD5044 (3 mg/kg or 6 mg/kg), or 3 different dose combinations of RBD7022 and RBD5044, as well as PBS control. All animals were administrated once on Day 1. Plasma was collected to quantify lipid biomarkers. Results RBD7022 showed a robust effect on LDL-C reduction, with inhibition rates of 45% in 3 mg/kg and 43% in 6 mg/kg, indicating 3 mg/kg was a saturated dose for RBD7022 in LDL-C lowering. RBD5044 showed a dose-dependent effect on LDL-C reduction, with inhibition rate of 52% at 1 mg/kg and 59% at 3 mg/kg. Interestingly, significantly enhanced LDL-C reduction was observed in the combination groups, with 67% reduction in LDL-C at RBD5044 1 mg/kg plus RBD7022 3 mg/kg, 73% reduction in LDL-C at RBD5044 3 mg/kg plus RBD7022 3 mg/kg and 78% reduction in LDL-C at RBD5044 3 mg/kg plus RBD7022 6 mg/kg, showing dose-dependent effects (Figure 1A). Enhanced TC reduction was also found in combination at RBD5044 3 mg/kg plus RBD7022 6 mg/kg compared with RBD5044 or RBD7022 alone. RBD5044 showed a dose dependent effect on TG reduction with inhibition rates of 56% at 1 mg/kg and 83% at 3 mg/kg. RBD7022 treatment alone did not show significant effect on TG reduction. No added effects of RBD7022 on TG levels was found in the combination with RBD5044, indicating the TG lowering was induced by RBD5044. Conclusions The combination of RBD7022 targeting PCSK9 and RBD5044 targeting APOC3 simultaneously reduce LDL-C and TC levels. The combination of RBD7022 and RBD5044 could be a better therapeutic option to further reduce LDL-C, particularly for mixed hyperlipidemia patients and other high-risk individuals with both high LDL-C and high TG levels.Figure 1

Advanced lipid testing in children: a call for pediatric reference intervals

Abstract Introduction Abnormal serum lipid levels in childhood are associated with dyslipidemia and increased risk of cardiovascular disease in adulthood. High prevalence of childhood obesity in the US has increased concerns about the adverse effects of abnormal lipids in children, prompting recommendations for universal lipid screening in adolescents. While specialized analysis of lipoproteins by nuclear magnetic resonance (NMR) has been predominately used in adults with risk factors for CVD, our laboratory also receives pediatric samples for NMR testing, most commonly associated with diagnostic codes for hyperlipidemia and/or abnormal weight gain. Currently adult-based reference ranges for the NMR lipoprotein measurements are used in children. The objective of this pilot study was to compare lipoprotein profiles of healthy adults and children and to assess the impact of reference intervals for children on clinical interpretation of pediatric results. Methods Serum samples were collected from 60 healthy children, ages 1 – 17 years, and 148 healthy adults, ages 19 – 64 years old. NMR lipoprotein analysis was performed using the Axinon lipoFIT by NMR assay on a 600 MHz NMR (Bruker). Statistical analysis was conducted in Excel and GraphPad Prism. Reference intervals (RIs) were determined in EP Evaluator as the central 95% interval. Results The levels of atherogenic low-density lipoprotein particle number (LDL-P) and small LDL-P (sLDL-P) were significantly lower in children compared to adults: 783±222 vs 1212±412 nmol/L and 302±142 vs 498±306 nmol/L, respectively (p<0.00001). Additionally, LDL size (LDL-s) was significantly larger in children than adults (21.23±0.29 vs 21.06±0.44 nm, p=0.006), reflecting prevalence of less dense LDL-P in the former group. Pediatric samples also had lower number of anti-atherogenic high-density lipoprotein particles (HDL-P) compared to adults: 29.4±4.6 vs 33.5±4.6 µmol/L, p<0.00001. The significant differences in the number and size of lipoprotein particles between adults and children implies that currently used adult reference intervals might not be appropriate for evaluating pediatric NMR samples. Therefore, we estimated RIs for our heathy pediatric and adult cohorts and applied these RIs to our retrospective data of 618 samples from children 1-17 years old, which were submitted for NMR lipoprotein testing in recent years. The analysis showed that using the adult RIs, 37% and 27% of pediatric samples would not flag for abnormally elevated LDL-P and sLDL-P, respectively; but they would be flagged based on the RI derived from our pediatric cohort. Moreover, 12% pediatric samples flagged for low HDL-P would have normal HDL-P levels if pediatric RIs are used instead of adult RIs. Conclusions Use of adult reference intervals in children may result in misclassification of lipid status and underestimation or overestimation of dyslipidemia and CVD risk in children. This pilot study highlights the need for pediatric reference intervals to guide interpretation of advanced lipid testing in children.

A-227 One Step Toward Implementation of Advanced Lipoprotien Testing in Children: A Pilot Study on Pediatric Reference Ranges

Abstract Background Abnormal serum lipid levels in childhood are associated with dyslipidemia and increased risk of cardiovascular disease in adulthood. High prevalence of childhood obesity in the US has increased concerns about the adverse effects of abnormal lipids in children, prompting recommendations for universal lipid screening in adolescents. While specialized analysis of lipoproteins by nuclear magnetic resonance (NMR) has been predominately used in adults with risk factors for CVD, our laboratory also receives pediatric samples for NMR testing, most commonly associated with diagnostic codes for hyperlipidemia and/or abnormal weight gain. Currently adult-based reference ranges for the NMR lipoprotein measurements are used in children. The objective of this pilot study was to compare lipoprotein profiles of healthy adults and children and to assess the impact of reference intervals for children on clinical interpretation of pediatric results. Methods Serum samples were collected from 60 healthy children, ages 1 - 17 years, and 148 self-identified healthy adults, ages 19 - 64 years old. NMR lipoprotein analysis was performed using the Axinon lipoFIT by NMR assay on a 600 MHz NMR (Bruker). Statistical analysis was conducted in Excel and Graph Pad Prism. Reference intervals (RIs) were determined in EP Evaluator as the central 95% interval. Results The levels of atherogenic low-density lipoprotein particle number (LDL-P) and small LDL-P (sLDL-P) were significantly lower in children compared to adults: 783±222 vs 1212±412 nmol/L and 302±142 vs 498±306 nmol/L, respectively (p<0.00001). Additionally, LDL size (LDL-s) was significantly larger in children than adults (21.23±0.29 vs 21.06±0.44 nm, p=0.006), reflecting prevalence of less dense LDL-P in the former group. Pediatric samples also had lower number of anti-atherogenic high-density lipoprotein particles (HDL-P) compared to adults: 29.4±4.6 vs 33.5±4.6 µmol/L, p<0.00001. The significant differences in the number and size of lipoprotein particles between adults and children implies that currently used adult reference intervals might not be appropriate for evaluating pediatric NMR samples. Therefore, we estimated RIs for our heathy pediatric and adult cohorts and applied these RIs to our retrospective data of 618 samples from children 1-17 years old, which were submitted for NMR lipoprotein testing in recent years. The analysis showed that using the adult RIs, 37% and 27% of pediatric samples would not flag for abnormally elevated LDL-P and sLDL-P, respectively; but they would be flagged based on the RI derived from our pediatric cohort. Moreover, 12% pediatric samples flagged for low HDL-P would have normal HDL-P levels if pediatric RIs are used instead of adult RIs. Conclusions Use of adult reference intervals in children may result in misclassification of lipid status and underestimation or overestimation of dyslipidemia and CVD risk in children. This pilot study highlights the need for pediatric reference intervals to guide interpretation of advanced lipid testing in children.

Elderly patients with very high plasma lipoprotein(a) concentrations and few cardiovascular consequences: a case series.

Lipoprotein(a) (Lp(a)) is an atherogenic low-density lipoprotein (LDL)-like particle that is currently regarded as a non-modifiable risk factor for atherosclerotic cardiovascular disease. The number of patients detected with elevated Lp(a) concentrations has been increasing in recent years, although the implication of this finding is unclear for patients and physicians. We screened our lipid clinic database for patients aged >65 years with very high Lp(a) concentrations, which were defined as >230 nmol/L, and cardiovascular outcomes were assessed. The patients' (n = 16) mean (±standard deviation) age was 72.2 ± 7.1 years and the mean Lp(a) concentration was 313 ± 68 nmol/L. After a cumulative 129.0 patient-year follow-up (mean: 8.1 ± 4.2 years), the mean age was 80.3 ± 7.0 years. We observed a low baseline prevalence of cardiovascular events, with only two patients having a history of cardiovascular events. Furthermore, zero incident adverse cardiovascular events were recorded over the follow-up. Therefore, very high Lp(a) concentrations and disease-free old age are not mutually exclusive. Our aggregated clinical experience is that there is only a modest association between elevated Lp(a) concentrations and adverse outcomes. Nonetheless, we still advise treating modifiable risk factors in these patients.

Mitochondrial Genome Editing: Exploring the Possible Relationship of the Atherosclerosis-Associated Mutation m.15059G>A With Defective Mitophagy.

The aim of this study was to evaluate the effect of the m.15059G>A mitochondrial nonsense mutation on cellular functions related to atherosclerosis, such as lipidosis, pro-inflammatory response, and mitophagy. Heteroplasmic mutations have been proposed as a potential cause of mitochondrial dysfunction, potentially disrupting the innate immune response and contributing to the chronic inflammation associated with atherosclerosis. The human monocytic cell line THP-1 and cytoplasmic hybrid cell line TC-HSMAM1 were used. An original approach based on the CRISPR/Cas9 system was developed and used to eliminate mitochondrial DNA (mtDNA) copies carrying the m.15059G>A mutation in the MT-CYB gene. The expression levels of genes encoding enzymes related to cholesterol metabolism were analyzed using quantitative polymerase chain reaction. Pro-inflammatory cytokine secretion was assessed using enzyme-linked immunosorbent assays. Mitophagy in cells was detected using confocal microscopy. In contrast to intact TC-HSMAM1 cybrids, Cas9-TC-HSMAM1 cells exhibited a decrease in fatty acid synthase (FASN) gene expression following incubation with atherogenic low-density lipoprotein. TC-HSMAM1 cybrids were found to have defective mitophagy and an inability to downregulate the production of pro-inflammatory cytokines (to establish immune tolerance) upon repeated lipopolysaccharide stimulation. Removal of mtDNA harboring the m.15059G>A mutation resulted in the re-establishment of immune tolerance and the activation of mitophagy in the cells under investigation. The m.15059G>A mutation was found to be associated with defective mitophagy, immune tolerance, and impaired metabolism of intracellular lipids due to upregulation of FASN in monocytes and macrophages.

Effects of fabomatisol under lead intoxication in rat experiment

The conducted study indicates the priority use of the drug fabomatizole to protect living systems from the negative effects of lead acetate.Aim: To study the mechanisms of fabomatizole effect on the nature of changes in redox reactions, NO-forming function of the endothelium, cholesterol metabolism and functional parameters in rats with lead intoxication.Material and Methods. The study was carried out on 60 Wistar rats. Lead intoxication was induced by intramuscular administration of lead acetate at a dose of 5 mg/kg of animal weight for a month. At the end of the intoxication period, Fabomatizol was administered at a dose of 10 mg/kg for a month. Next, blood and tissue samples were taken from rats to determine the activity of oxidative, antioxidant, enzymatic systems, nitric oxide metabolism, and blood lipid spectrum.Results. The data obtained showed that intramuscular administration of fabomatisol in case of lead intoxication has an antioxidant effect and inhibits lipid peroxidation (LPO) activity. Under the influence of fabomatizol, nitric oxide metabolism andtotal nitric oxide metabolites (NOx) content significantly increased, and a negative correlation was found between the malondialdehyde level, superoxide dismutase activity and NOx. At the same time, the study found a decrease in the expression level of eNOS as the cause of a reduced concentration of NOx in the blood. L-arginine availability for eNOS was disturbed by atherogenic low density lipoprotein (LDL). Treatment with fabomatizol against the background of lead intoxication caused a decrease in total cholesterol, LDL cholesterol and an increase inhigh density lipoprotein cholesterol. By inhibiting lipid peroxidation in the cells of the renal and hepatic tissues, fabomatizol contributed to the restoration of lipid-protein interactions and the functional activity of Na and K-activated ATPase in the renal interstitium. Simultaneously, there is an activation of Na,K-ATP-ase in the hepatocyte and a decrease in the level of organ-specific enzymes in the blood plasma.Conclusion. The results obtained are evidence of the antioxidant properties of fabomatisol in lead intoxication, its ability to induce the activity of antioxidant system (AOS enzymes, stimulate the NO-forming function of the endothelium, NOx production and the activity of the membrane enzyme – Na,K-ATP-ase in the renal and hepatic tissues and reduce the level of organ-specific enzymes in blood plasma.

Lipid-lowering Eeficacy and Safety of High Doses of Atorvastatin and Rosuvastatin

Administration of high doses of atorvastatin 80 mg/day and rosuvastatin 40 mg/day is a part of a standard algorithm for the treatment of patients at high and very high cardiovascular risk. This treatment allows reducing atherogenic low-density lipoprotein cholesterol (LDL-C) by approximately 50 % and decreasing the risk of cardiovascular diseases. Results of prospective studies with atorvastatin and rosuvastatin demonstrated a significant (45-55 %) decrease in LDL-C and triglycerides (11-50 %). This article focuses on analysis of evidence-based retrospective database for atorvastatin and rosuvastatin in prospective studies; reviewing a retrospective database of the VOYAGER study, including subgroups of patents with type 2 diabetes mellitus or hypertriglyceridemia; evaluation of the variability of the hypolipidemic response; and analysis of the risk for development of cardiovascular diseases and their complications with the statin treatment. Rosuvastatin at the highest daily dose of 40 mg/day was superior to atorvastatin 80 mg/day by the capability for decreasing LDL-C. Both statins showed a great variability in the degree of reducing triglycerides and exerted a minimal effect on high-density lipoprotein cholesterol. According to results of completed studies, rosuvastatin 40 mg/day also was superior to high doses of atorvastatin by tolerability and safety.

Comparative Susceptibility to Oxidation of Different Classes of Blood Plasma Lipoproteins.

The kinetics of free radical peroxidation of different classes of blood plasma lipoproteins (nanoparticles involved in lipid transport in the body) was studied. The susceptibility of atherogenic low-density lipoproteins (LDLs) to the Cu2+-initiated free radical peroxidation in vitro was found to be more than ten times higher than that of antiatherogenic high density lipoproteins (HDLs). The baseline content of acyl hydroperoxy derivatives of phospholipids (primary products of free radical peroxidation) in the outer layer of LDL particles in vivo measured per particle exceeded the baseline content of these compounds in HDL particles by more than an order of magnitude. The susceptibility to oxidation of the HDL2 subfraction of HDLs was higher than the susceptibility of total HDL fraction and HDL3 subfraction. The data obtained confirm an important role of free radical peroxidation of LDLs in the molecular mechanisms of vascular wall damage in atherosclerosis.

Protein S on the surface of plasma lipoproteins: a potential mechanism for protein S delivery to the atherosclerotic plaques?

The anticoagulant protein S (PS) binds phospholipids with very high affinity, but PS interaction with lipoproteins and lipidrich atherosclerotic plaques remains still poorly defined. We investigated PS in plasma lipoproteins and in atherosclerotic plaques from ten patients undergoing endarterectomy. PS was detected by Western blotting after exposure of the necrotic core to liposomes and was found to maintain its ability to bind phosphatidylserine micelles. The amounts of PS bound to low/very low-density lipoproteins in patient’ plasmas were higher and more variable than those detected in healthy subjects. A direct correlation between bound PS and low-density lipoproteins (LDL), plasma levels was found only in patients (r=0.921, p<0.001), thereby leading to hypothesize that the PS-phospholipids binding may increase by oxidative processes of LDL in atherosclerotic patients. The presence of the PS into the necrotic core of atherosclerotic plaques and on the surface of lipoproteins, particularly the atherogenic LDL, suggests a LDL-based delivery of PS to the atherosclerotic plaques and emphasizes the deep link between plasma lipids and coagulation in cardiovascular diseases.

Statin therapy is not associated with insulin resistance in children and adolescents with familial hypercholesterolaemia

Background and Aims : Statins are first line therapy for lowering atherogenic low-density lipoprotein cholesterol (LDL-C) in patients with familial hypercholesterolaemia (FH). Statins were associated with an increased insulin resistance and the risk for type 2 diabetes. We aimed to assess the effect of statins on insulin resistance in children.

The main side effects of statins in clinical practice

Statins have long occupied a central place in cardiovascular medicine, being an integral component of the prevention and treatment of atherosclerotic cardiovascular diseases (coronary heart disease and its main clinical forms, angina pectoris and myocardial infarction; transient ischemic attacks, ischemic strokes, etc.). By blocking a key enzyme of cholesterol biosynthesis, 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA-reductase), statins normalize the parameters of the lipid spectrum, primarily, the serum levels of atherogenic low-density lipoprotein cholesterol. However, in addition to the beneficial effects of statins, side effects are also characteristic, which are a significant problem in modern clinical practice due to the fact that they can cause dangerous disorders, forcing physicians to reduce dosages or completely cancel these drugs. Understanding the side effects and the mechanisms underlying their formation is important for improving the measures for the early detection, prevention and treatment of those disorders. This article discusses such side effects of statins as myotoxicity, hepatotoxicity, nephrotoxicity. The pathogenetic mechanisms underlying these toxic effects of statins are discussed. A particular attention is paid to the effect of statins on the oxidative stress, the mechanisms of oxidative damage to cellular macromolecules (lipids, proteins and DNA) and their potential role in the development of myotoxicity, hepatotoxicity and nephrotoxicity.

Статины и окислительный стресс при сердечно-сосудистой патологии

Statins are a highly effective class of lipid-lowering drugs for the prevention of the risk of developing cardiovascular pathology. The main mechanism of action of statins is based on the inhibition of cholesterol formation, which leads to a decrease in serum levels of total cholesterol and atherogenic low-density lipoproteins. However, in addition to the main hypolipidemic effect, statins also have a significant effect on oxidative stress. This article discusses in detail the effect of statins on oxidative stress and its significance for cardiovascular pathology.

Atherogenicity of low-density lipoproteins after switching from a protease inhibitor to dolutegravir: a substudy of the NEAT022 study.

The aim of this study was to investigate whether switching from a ritonavir-boosted PI-based regimen to a dolutegravir-based regimen improved the atherogenic properties of LDL particles in patients with HIV. This was a substudy of the NEAT022 study (ClinicalTrials.gov NCT02098837). Adults with HIV with a Framingham score >10% or aged >50 years and being treated with a stable boosted PI-based regimen were randomized to either switch to dolutegravir or continue with boosted PI. At baseline and Week 48, we assessed atherogenic LDL properties: LDL particle size and phenotype (A, intermediate, B), oxidized LDL (ox-LDL) and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Eighty-six participants (dolutegravir 44; PI 42) were included. Participants had a median (IQR) age of 54 (51-57) years and 79.1% were male. In the dolutegravir arm, after 48 weeks, we observed: (1) an increase in LDL size [median 1.65 Å (IQR -0.60 to 4.20); P = 0.007], correlated with the decrease in triglyceride concentration [Spearman correlation = -0.352 (P = 0.001)], with a corresponding decrease of subjects with atherogenic LDL phenotype B (36.4% to 20.5%; P = 0.039); (2) a decrease in Lp-PLA2 activity [median 1.39 μmol/min/mL (IQR -2.3 to 0.54); P = 0.002]; and (3) a decrease in ox-LDL [median 14 U/L (IQR -102 to 13); P = 0.006]. In the PI arm, none of these favourable lipid modifications was observed. Forty-eight weeks after switching from a PI-based to a dolutegravir-based regimen, patients with Framingham score >10% or aged >50 years showed improvement of several atherogenic lipid features, including LDL particle phenotype, ox-LDL and Lp-PLA2.

Well-posedness of a mathematical model of diabetic atherosclerosis with advanced glycation end-products

Atherosclerosis is a leading cause of death worldwide; it emerges as a result of multiple dynamical cell processes, including hemodynamics, endothelial damage, innate immunity and sterol biochemistry. Making matters worse, nearly 463 million people have diabetes, which increases atherosclerosis-related inflammation, diabetic patients are twice as likely to have a heart attack or stroke. The pathophysiology of diabetic vascular disease is generally understood. Dyslipidemia with increased levels of atherogenic low-density lipoprotein, hyperglycemia, oxidative stress and increased inflammation are factors that increase the risk and accelerate development of atherosclerosis. In a recent paper, Xie [Well-posedness of a mathematical model of diabetic atherosclerosis. J Math Anal Appl. 2022;505(2):125606], we have developed a mathematical model that includes the effect of hyperglycemia and insulin resistance on plaque growth. In this paper, we propose a more comprehensive mathematical model for diabetic atherosclerosis which include more variables; in particular, it includes the variable for Advanced Glycation End-Products (AGEs) concentration. Hyperglycemia trigger vascular damage by forming AGEs, which are not easily metabolized and may accelerate the progression of vascular disease in diabetic patients. The model is given by a system of partial differential equations (PDEs) with a free boundary. We also establish the local existence and uniqueness of solution to the model. The methodology is to reduce the free boundary to a fixed boundary and the system of PDEs to an abstract evolution equation in Banach spaces, and apply the theory of analytic semigroup.

Postprandial plasma glucose excursion is associated with an atherogenic lipid profile in individuals with type 2 diabetes mellitus: A cross-sectional study.

Coronary heart disease (CHD) is a prevalent complication of type 2 diabetes mellitus (T2DM). The atherogenic low-density lipoprotein (LDL) cholesterol is an established risk factor of cardiovascular disease, and evidence also suggests that postprandial plasma glucose (PPG) levels closely delineate CHD mortality in diabetes. The investigators hypothesized that postprandial plasma glucose excursion (PPGE), defined as the difference between 2-hour PPG and fasting plasma glucose (FPG), may be associated with plasma LDL cholesterol levels in patients with T2DM. This study enrolled diabetic participants for whom FPG and lipid profile were sampled after a 12-hour fast, followed by PPG sampling two hours after consuming a standard meal with 75 grams of carbohydrates. The study enrolled 379 participants who were divided into PPGE tertiles according to the difference between their 2-hour PPG and FPG. Participants in the highest PPGE tertile had considerably greater plasma LDL cholesterol levels than patients in the lowest tertile (126.7 mg/dL vs. 99.5 mg/dL, P <0.001). Linear regression analysis also demonstrated that the PPGE was positively correlated with plasma LDL cholesterol levels (β coefficient: 0.165, P < 0.001). Postprandial glucose excursion positively correlated with plasma LDL cholesterol levels in individuals with T2DM. Participants with raised PPGE harbored greater LDL cholesterol levels than those with lower postprandial glucose fluctuations. Therefore, postprandial glucose excursion is associated with an atherogenic lipid profile and may be a modifiable risk factor of diabetic CHD.

Children with familial hypercholesterolemia display changes in LDL and HDL function: A cross-sectional study.

The functional status of lipoprotein particles contributes to atherogenesis. The tendency of plasma low-density lipoprotein (LDL) particles to aggregate and the ability of igh-density lipoprotein (HDL) particles to induce and mediate reverse cholesterol transport associate with high and low risk for cardiovascular disease in adult patients, respectively. However, it is unknown whether children with familial hypercholesterolemia (FH) display lipoprotein function alterations. We hypothesized that FH children had disrupted lipoprotein functions. We analyzed LDL aggregation susceptibility and HDL-apoA-I exchange (HAE), and activity of four proteins that regulate lipoprotein metabolism (cholesteryl ester transfer protein, lecithin-cholesterol acyltransferase, phospholipid transfer protein, and paraoxonase-1) in plasma samples derived from children with FH (n = 47) and from normocholesterolemic children (n = 56). Variation in lipoprotein functions was further explored using an nuclear magnetic resonance-based metabolomics profiling approach. LDL aggregation was higher, and HAE was lower in FH children than in normocholesterolemic children. LDL aggregation associated positively with LDL cholesterol (LDL-C) and negatively with triglycerides, and HAE/apoA-I associated negatively with LDL-C. Generally, the metabolomic profile for LDL aggregation was opposite of that of HAE/apoA-I. FH children displayed increased atherogenicity of LDL and disrupted HDL function. These newly observed functional alterations in LDL and HDL add further understanding of the risk for atherosclerotic cardiovascular disease in FH children.

T-Cadherin and the Ratio of Its Ligands as Predictors of Carotid Atherosclerosis: A Pilot Study.

In the cardiovascular system, atherogenic low-density lipoproteins (LDL) and the protective hormone adiponectin bind to the same receptor, T-cadherin. In this study, we tested the hypothesis that the ratio of circulating LDL to high-molecular weight (HMW) adiponectin could predict the development of atherosclerosis. Using enzyme-linked immunosorbent assay, we measured the level of circulating HMW adiponectin in the blood of donors together with ultrasound measuring of intima-media thickness (IMT) of carotid arteries. Single-nucleotide polymorphisms in the T-cadherin gene were identified using polymerase chain reaction. We found that carotid artery IMT is inversely correlated with the level of HMW in male subjects. We also found that the G allele of rs12444338 SNP in the T-cadherin gene correlates with a lower level of circulating T-cadherin and thinner IMT and therefore could be considered as an atheroprotective genotype. Despite our data, we could not provide direct evidence for the initial study hypothesis. However, we did uncover an important correlation between circulating T-cadherin and thinner carotid IMT.

The interplay between ER stress, inflammation, and lipid metabolism

Background and Aims: The endoplasmic reticulum (ER) stress is an important event in the pathogenesis of human diseases, including atherosclerosis. ER stress may lead to foam cell formation and pro-inflammatory cytokines production in macrophages. In atherosclerosis, several cell types can be affected by ER stress, including endothelial cells, macrophages, and smooth muscle cells. Atherogenic low-density lipoproteins and/or inflammatory cytokines can induce ER stress, which can promote lipid accumulation and cytokine production in macrophages.

Dietary Interventions Reduce Traditional and Novel Cardiovascular Risk Markers by Altering the Gut Microbiome and Their Metabolites.

Aims: The current study investigates the role of diet in mediating the gut microbiome-cardiovascular association which has not yet been explored in humans.Methods and Results: Using a two-arm dietary intervention study in healthy participants (N = 70), we assessed the effects of omega-3 and fibre supplementation on gut microbiome composition and short-chain fatty acid (SCFA) production. We then investigated how changes in gut microbiome composition correlated with changes in traditional cardiovascular risk factors (cholesterol, triglycerides, blood pressure), cytokines, and novel validated markers such as GlycA and ceramides, previously linked to CVD incidence and mortality. Both interventions resulted in significant drops in blood pressure, cholesterol, proinflammatory cytokines, GlycA and ceramides (all P < 0.05). Decreases in the atherogenic low-density lipoprotein triglyceride fraction, in total serum cholesterol were correlated with increases in butyric acid-production [β(SE) = −0.58 (0.06), P < 0.001; −0.53 (0.04), P < 0.001] and nominally associated with increases in some butyrogenic bacteria. Drops in GlycA were linked to increases in Bifidobacterium [β(SE) = −0.32 (0.04), P = 0.02] and other SCFAs including acetic acid [β(SE) = −0.28 (0.04), P = 0.02] and propionic acid [β(SE) = −0.3 (0.04), P = 0.02]. Additionally, we report for the first-time reductions in specific ceramide ratios that have been shown to predict CVD mortality and major adverse cardiovascular events such as d18:1/16:0, d18:0/24:0, and d18:1/24:1 which were associated with the reduction in the abundance in Colinsella and increases in Bifidobacteriuim and Coprococcus 3 and SCFAs (all P < 0.05).Conclusion: Overall, these findings support the potential of using simple dietary interventions to alter validated biomarkers linked to cardiovascular risk via the gut microbiome composition and its metabolic functions.