HDL Subfractions Research Articles

Perturbations in plasma amino acid and lipoprotein subfraction profiles in anorexia nervosa before and after refeeding: A metabolomic cross-sectional and longitudinal analysis.

Anorexia nervosa (AN) is a life-threatening eating disorder, which is increasingly being considered a metabo-psychiatric condition. We aimed to assess how the lipoprotein subfraction and plasma metabolome are altered in acutely underweight patients with AN (AcAN), if they change with short-term weight-restoration, and whether these changes point towards altered cardiometabolic risk. Using nuclear magnetic resonance spectroscopy, we measured and compared the plasma concentrations of 132 metabolites, aminoacids and lipoprotein subfractions in young female patients with AcAN before (n=72) versus after (n=46) a short-term inpatient refeeding program resulting in weight-restoration (longitudinal analysis), as well as versus female healthy control (HC) participants of similar age (n=74) (cross-sectional analysis). Patients with AcAN showed elevated plasma cholesterol levels due to higher concentrations of small and dense Low Density Lipoprotein (LDL-6) and of large and less dense High Density Lipoprotein (HDL-1) subfractions compared to HC. Additionally, they had lower plasma concentrations of branched chain amino acids and glucose and higher concentrations of the gluconeogenic amino acids glutamine, alanine and methionine. Refeeding elevated the plasma cholesterol levels further, but with a different pattern compared to AcAN, by increasing the concentrations of the larger and less dense LDL (LDL-1, LDL-2, LDL-3) particles and of smaller and more dense HDL (HDL-2, HDL-3) subfractions. However, refeeding only partially restored the amino acid concentrations. Lipoprotein profiles in AcAN point towards a potentially elevated risk for atherosclerosis; an altered lipoprotein profile was also detected after refeeding. Metabolite profiles in AcAN indicate an advanced catabolic state with only partial restoration after refeeding.

Inflammatory Biomarkers and Lipid Parameters May Predict an Increased Risk for Atrial Arrhythmias in Patients with Systemic Sclerosis.

Autoimmune inflammation enhances the electrical instability of the atrial myocardium in patients with systemic sclerosis (SSc); thus, atrial arrhythmia risk is increased, which might be predicted by evaluating the P wave interval and dispersion of a 12-lead surface electrocardiogram (ECG). We examined 26 SSc patients and 36 healthy controls and measured the P wave interval and P wave dispersion of the 12-lead surface ECG in each patient. Furthermore, echocardiography and 24-h Holter ECG were performed and levels of inflammatory laboratory parameters, including serum progranulin (PGRN), sVCAM-1, sICAM-1, leptin and C-reactive protein (CRP), were determined. Lipid parameters, such as Apo A-I, LDL-cholesterol (LDL-C), oxidized LDL (oxLDL) and the LDL and HDL subfractions were also evaluated. The P wave interval showed a significant positive correlation with the levels of Apo A-I, LDL-C, CRP, sVCAM-1, sICAM-1 and leptin. The oxLDL level correlated positively with P wave dispersion. Of note, significant positive correlation was also found between the large HDL percentage and the P wave interval. Our results suggest that PGRN, sVCAM-1, sICAM-1, leptin, CRP, LDL-C and oxLDL, along with LDL and HDL subfractions, might have a role in atrial arrhythmogenesis in patients with SSc.

Electronegative ApoCIII-Rich HDL promotes cellular damage and vascular aging

Abstract Background Experimental studies attributing HDL a cardioprotective effect are challenged by well-designed randomized controlled trials showing largely neutral results, which might be related to more recent observations that certain HDL particles exert detrimental effects. This study explores the effects of electronegative HDL on cellular damage and vascular aging. Using anion-exchange chromatography, HDL was divided into five subclasses (H1 to H5) based on increasing electronegativity. Compared to the health-promoting H1, the most electronegative subclass, H5 contains significantly higher levels of ApoCIII and triglycerides (TG). Purpose Herein, we aim to explore the cellular and molecular mechanisms underpinning H5-induced pathology in human umbilical vein vascular endothelial cells (HUVECs), which may accelerate vascular aging preceding the development of atherosclerotic cardiovascular disease (ASCVD). Methods H1 and H5 were isolated from patients with metabolic syndrome (MetS). To gauge the impact of H5 on vascular integrity, HUVECs were treated with solvent, H1, or H5 at concentrations of 25, 50, or 100 µg/mL. Cell viability and apoptosis were evaluated using the MTT assay and PI/Calcein fluorescent staining, respectively. Immunofluorescence staining and immunoblotting, focusing on 8-oxodG, P53, and β-gal, proxies of DNA damage and cellular senescence, were performed. Senescence-associated secretory phenotype (SASP) analysis was done to elucidate the senescent mechanism. By harnessing Mitosox imaging reactive oxygen species (ROS) synthesis was monitored. Finally, unbiased lipid- and transcriptomics were used to identify lipid components potentially involved in H5 signaling. Results As compared to controls, MetS patients exhibited more electronegative HDL particles, as indicated by increased H5 (1.604±0.410% vs 4.598±4.712%, P=0.0016). Remarkable elevations were noted in individuals with severe clinical complications, as shown in the representative patient with left ventricular hypertrophy, chronic coronary syndrome, and heart failure (Fig. 1). In HUVECs, H5 but not H1 reduced cell viability and increased apoptosis in a concentration-dependent manner. In parallel, H5 but not H1 induced cell aging, ROS production, and DNA damage, with SASP cytokines including IL-1β, IL-6, CCL2, TNF-α, and γH2AX (Fig. 1). Notably, compared to H1, H5 exhibited high contents of various TG species, impairing H5’s anti-inflammatory and antioxidant capacities, along with reductions in several phosphatidylcholines that may constitute essential cell membrane structural components, as evidenced by lipidomic studies (Fig. 2). Conclusion H5, the most electronegative and dysfunctional HDL subfraction, is capable of inducing DNA damage, oxidative stress, and senescence in vascular ECs. Its notable elevation in patients with MetS highlights a previously unrecognized etiology, shedding light on how electronegative HDL may contribute to and expedite ASCVD.Fig 1Fig 2

Nutritional effect on lipoproteins and their subfractions in patients with Psoriatic Arthritis: a 12-week randomized trial—the DIETA trial

IntroductionPatients with psoriatic arthritis have some lipid metabolism changes and higher risk of metabolic syndrome (MetS) and cardiovascular diseases, regardless of traditional risk factors, suggesting that chronic inflammation itself plays a central role concerning the atherosclerosis. However, there is a lack of information regarding atherogenic pattern and lipoprotein subfractions burden in these individuals.AimTo evaluate the HDL and LDL-cholesterol plasmatic levels and their subfractions after a nutritional intervention in patients with psoriatic arthritis (PsA).MethodsThis was a randomized, placebo-controlled clinical trial of a 12-week nutritional intervention. PsA patients were randomly assigned to 1-Placebo: 1 g of soybean oil daily, no dietetic intervention; 2-Diet + Supplementation: an individualized diet, supplemented with 604 mg of omega-3 fatty acids, three times a day; and 3-Diet + Placebo: individualized diet + 1 g of soybean oil. The LDL subfractions were classified as non-atherogenic (NAth), atherogenic (Ath) or highly atherogenic (HAth), whereas the HDL subfractions were classified as small, medium, or large particles, according to the current recommendation based on lipoproteins electrophoresis.ResultsA total of 91 patients were included in the study. About 62% of patients (n = 56) had an Ath or HAth profile and the main risk factors associated were male gender, longer skin disease duration and higher BMI. Thirty-two patients (35%) had a high-risk lipoprotein profile despite having LDL plasmatic levels below 100 mg/dL. The 12-week nutritional intervention did not alter the LDL subfractions. However, there were significant improvement of HDL subfractions.ConclusionRecognizing the pro-atherogenic subfractions LDL pattern could be a relevant strategy for identifying PsA patients with higher cardiovascular risk, regardless total LDL plasmatic levels and disease activity. In addition, a short-term nutritional intervention based on supervised and individualized diet added to omega-3 fatty acids changed positively the HDLLARGE subfractions, while LDLLARGE subfraction was improved in hypercholesterolemic individuals.ClinicalTrials.gov identifier: NCT03142503 (http://www.clinicaltrials.gov/).

#1672 High level of HDL-C is associated with a higher risk of ESRD and all-cause mortality in patients with DM and CKD

Abstract Background and Aims Previous studies have regarded high-density lipoprotein cholesterol (HDL-C) as ‘good cholesterol’; however, recent research has unveiled a higher incidence of adverse events among individuals with extremely elevated HDL-C levels. Method Two cohorts of subjects were analyzed in this study. In the first cohort, a total of 375 participants with DKD who underwent renal-biopsy between January 2008 and September 2020, from West China Hospital T2DM-DKD cohort, were enrolled for the longitudinal observational study. Additionally, 3,262 participants with DM and chronic kidney disease (CKD) from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 were included. Kaplan-Meier curves and Cox proportional hazard models were used to analyze the association between HDL-C concentration and the incidence of end-stage renal disease (ESRD) as well as all-cause mortality. Results Patients were divided into three groups based on HDL-C levels. After a median follow-up of 36 months, 44% of the patients developed ESRD in T2DM-DKD cohort. Patients in Group 3 (HDL-C ≥1.55 mmol/L) exhibited a higher risk of ESRD compared to Group 1 (HDL-C <1.03 mmol/L). After adjusting for confounders, Group 3 patients still had a significantly higher risk of ESRD (adjusted HR: 1.68, 95% CI: 1.03, 2.71). Analysis of HDL subfractions revealed that a higher HDL3/HDL2 ratio was associated with a lower risk of ESRD. Furthermore, in the NHANES cohort, higher HDL-C levels were linked to a higher risk of all-cause mortality during a median follow-up of 75 months as the result of the weighted Kaplan-Meier curves (p = 0.02). Notably, in patients with CKD stages 1-2, Group 3 participants had a significantly higher hazard ratio (HR: 1.61, 95% CI: 1.19, 2.19) after adjusting for confounders. Conclusion This study challenges the notion of HDL-C as ‘good cholesterol’ in patients with DKD, as higher HDL-C levels were associated with increased risks of ESRD and all-cause mortality. Additionally, the study highlights the potential protective effect of a higher HDL3/HDL2 ratio against ESRD. These findings contribute to reevaluating the role of HDL-C and its subfractions in DKD patients.

HDL-Cholesterol Subfraction Dimensional Distribution Is Associated with Cardiovascular Disease Risk and Is Predicted by Visceral Adiposity and Dietary Lipid Intake in Women.

HDL-cholesterol quality, including cholesterol distribution in HDL subfractions, is emerging as a key discriminant in dictating the effects of these lipoproteins on cardiovascular health. This study aims at elucidating the relationship between cholesterol distribution in HDL subfractions and CVD risk factors as well as diet quality and energy density in a population of pre- and postmenopausal women. Seventy-two women aged 52 ± 6 years were characterized metabolically and anthropometrically. Serum HDL-C subfractions were quantified using the Lipoprint HDL System. Cholesterol distribution in large HDL subfractions was lower in overweight individuals and study participants with moderate to high estimated CVD risk, hypertension, or insulin resistance. Cholesterol distribution in large, as opposed to small, HDL subfractions correlated negatively with insulin resistance, circulating triglycerides, and visceral adipose tissue (VAT). VAT was an independent positive and negative predictor of cholesterol distribution in large and small HDL subfractions, respectively. Furthermore, an increase in energy intake could predict a decrease in cholesterol levels in large HDL subfractions while lipid intake positively predicted cholesterol levels in small HDL subfractions. Cholesterol distribution in HDL subfractions may represent an additional player in shaping CVD risk and a novel potential mediator of the effect of diet on cardiovascular health.

The Interplay of Dyslipidemia, Oxidative Stress, and Clinical Outcomes in Acute Ischemic Stroke Patients with and without Coronary Artery Disease.

We assessed lipid and lipoprotein profiles, along with oxidative stress (OS) parameters, in patients within the crucial 24 h period following an acute ischemic stroke (AIS), comparing those with and without coronary artery disease (CAD). We aimed to correlate these measures with clinical condition scales (NIHSS, mRS) post-AIS. This study included 27 AIS patients without CAD (AIS group) and 37 AIS patients with CAD (CAD-AIS group). Using polyacrylamide gel electrophoresis (Lipoprint system), we determined plasma LDL and HDL subfractions. Spectrophotometric methods were used to assess plasma antioxidant capacity, lipoperoxides, homocysteine (HC) levels, paraoxonase1, and catalase activities. We also measured urine isoprostanes and the activities of antioxidant enzymes (SOD, GPx) with commercial kits. CAD-AIS patients had notably higher HC levels, while there were no significant differences in lipoprotein subfractions and OS parameters between both groups. In the AIS group, mRS scores showed negative correlations with catalase, GPx activities, and total cholesterol. In the CAD-AIS group, atherogenic lipoproteins (IDLC, LDL2, LDL3-7) exhibited a significant positive correlation with mRS. This study underscores the role of dyslipidemia and OS in the development of AIS and CAD. It emphasizes the complex connections between specific biomarkers and post-stroke clinical outcomes. Our results suggest a significant impact of CAD treatment on lipid profile but not on homocysteine levels. The traditional narrative associating high cholesterol as the ultimate risk factor for cardiovascular diseases needs to be challenged, at least with respect to neurological outcomes. These insights may guide more targeted therapeutic approaches.

High-Density Lipoprotein Particles and Torque Teno Virus in Stable Outpatient Kidney Transplant Recipients.

Torque teno virus (TTV) is emerging as a potential marker for monitoring immune status. In transplant recipients who are immunosuppressed, higher TTV DNA loads are observed than in healthy individuals. TTV load measurement may aid in optimizing immunosuppressive medication dosing in solid organ transplant recipients. Additionally, there is a growing interest in the role of HDL particles in immune function; therefore, assessment of both HDL concentrations and TTV load may be of interest in transplant recipients. The objective of this study was to analyze TTV loads and HDL parameters in serum samples collected at least one year post-transplantation from 656 stable outpatient kidney transplant recipients (KTRs), enrolled in the TransplantLines Food and Nutrition Cohort (Groningen, the Netherlands). Plasma HDL particles and subfractions were measured using nuclear magnetic resonance spectroscopy. Serum TTV load was measured using a quantitative real-time polymerase chain reaction. Associations between HDL parameters and TTV load were examined using univariable and multivariable linear regression. The median age was 54.6 [IQR: 44.6 to 63.1] years, 43.3% were female, the mean eGFR was 52.5 (±20.6) mL/min/1.73 m2 and the median allograft vintage was 5.4 [IQR: 2.0 to 12.0] years. A total of 539 participants (82.2%) had a detectable TTV load with a mean TTV load of 3.04 (±1.53) log10 copies/mL, the mean total HDL particle concentration was 19.7 (±3.4) μmol/L, and the mean HDL size was 9.1 (±0.5) nm. The univariable linear regression revealed a negative association between total HDL particle concentration and TTV load (st.β = -0.17, 95% CI st.β: -0.26 to -0.09, p < 0.001). An effect modification of smoking behavior influencing the association between HDL particle concentration and TTV load was observed (Pinteraction = 0.024). After adjustment for age, sex, alcohol intake, hemoglobin, eGFR, donor age, allograft vintage and the use of calcineurin inhibitors, the negative association between HDL particle concentration and TTV load remained statistically significant in the non-smoking population (st.β = -0.14, 95% CI st.β: -0.23 to -0.04, p = 0.006). Furthermore, an association between small HDL particle concentration and TTV load was found (st.β = -0.12, 95% CI st.β: -0.22 to -0.02, p = 0.017). Higher HDL particle concentrations were associated with a lower TTV load in kidney transplant recipients, potentially indicative of a higher immune function. Interventional studies are needed to provide causal evidence on the effects of HDL on the immune system.

High-density lipoprotein cholesterol subfraction HDL2 is associated with improved endothelial function in systemic lupus erythematosus

ObjectivePatients with systemic lupus erythematosus (SLE) have increased risk of premature atherosclerosis but the exact mechanisms remains unclear. Flow-mediated dilatation (FMD) is an established non-invasive assessment of vascular endothelial function....

HDL subfractions determined by microfluidic chip electrophoresis predict the vulnerability of intracranial plaque: A HRMRI study

AimHigh-density lipoprotein (HDL) can be divided into several subfractions based on density, size and composition. Accumulative evidence strongly suggests that the subfractions of HDL have very different roles in the pathogenesis of atherosclerosis. The purpose of this study was to further delineate the relationship between HDL subfractions extracted by microfluidic chip electrophoresis and the vulnerability of plaques in patients with intracranial atherosclerosis with a high-resolution magnetic resonance imaging (HRMRI) study. MethodsWe prospectively enrolled patients with single atherosclerotic plaque in the middle cerebral artery (MCA) or basilar artery (BA) between July 2020 and Dec 2022 and performed 3-tesla HRMRI on the relevant artery. The HDL cholesterol concentration and HDL subfractions (HDL-2a, HDL-2b and HDL-3) percentage were analyzed in serum samples from the same patients by electrophoresis on a microfluidics system. ResultsA total of 81 MCA or BA plaques [38 (46.9%) symptomatic and 43 (53.1%) asymptomatic] in 81 patients were identified on HRMRI. Patients with symptomatic plaques had a significantly lower HDL-2b level than asymptomatic plaques [symptomatic vs. asymptomatic: 0.16 (0.10–0.18) vs. 0.27(0.21–0.34), p = 0.001]. After adjusting for demographics and vascular risk factors, logistic regression showed that HDL-2b was inversely associated with asymptomatic plaques (B = −0.04, P = 0.017). According to receiver operating characteristic (ROC) curve model analysis, the cutoff point of HDL-2b in predicting asymptomatic plaques was 0.21 mmol/L (Area under curve: 0.719, specificity: 73.7%, sensitivity: 72.1%). Furthermore, plaque enhancement on HRMRI (P < 0.001), positive remodeling (P < 0.001), plaque load (P < 0.001) and luminal stenosis (P < 0.001) were superior among patients with HDL-2b < 0.21 mmol/L. ConclusionsOur data showed that serum HDL-2b levels may serve as a biomarker for predicting vulnerability in intracranial atherosclerotic plaques.

The concentration of small-diameter HDL particles (HDLp1) predicts the incidence of coronary calcium score in diabetic subjects without established cardiovascular disease

Abstract Introduction Type 2 diabetes (DM2) decisively influences the evolution of coronary atherosclerosis. However, this is a heterogeneous and poorly understood process. While in 50% of diabetics the chance of incident Coronary Calcium Score (CAC) in 5 years exceeds 40%, in 10% of diabetics the chance of incident CAC is less than 10%. To better understand the progression of coronary atherosclerosis measured by CAC in diabetics without cardiovascular disease, we studied the impact of the concentration of the small-diameter subfraction of HDL (HDLp1, 7 to 8nm). HDLp1 has been implicated as a central mediator of the anti-inflammatory effect of the HDL pool and could play a specific role in CAC incidence among diabetics. Methods From 2370 individual with two CAC evaluations and hydrogen spectroscopy/magnetic resonance (H1-NMR) plasma profile available, we found 461 diabetic individuals, non-users of statins, without previous cardiovascular disease, with CAC=0 in the first measurement and a second CAC measurement after an average period of 5 years. [HDLp1] concentration was measured by H1-NMR and divided into tertiles. The incidence of CAC was defined as an initial CAC of 0 followed by CAC&amp;gt;0 in the second measurement. Stepwise forward logistic regressions were used to identify risk factors for CAC incidence. Discrimination analysis was performed by calculating the area under the ROC curve (AUROC). Results A total of 143 (31.0%) patients had incident CAC. In stepwise logistic regression, alongside factors such as age, gender, systolic blood pressure, smoking, LDL-C, C-reactive protein and HbA1c, the 3rd tertile of [HDLp1] was associated with 55.2% (95% CI 15-110%, p =0.0039) and 140% (95% CI 32-341%, p&amp;lt;0.001) higher risk of CAC incidence compared to the 2nd tertile and 1st tertile, respectively. When compared to a model composed of 10 confounding variables (age, gender, systolic blood pressure, BMI, smoking, Lp(a), LDL-C,triglycerides, C-reactive protein and HbA1c) for predicting the incidence of CAC, the diameter of HDLp1 substantially increased the AUROC from 0.651 (95% CI 0.597-0.705) to 0.684 (95% CI 0.631–0.736), p=0.027 for the DeLong test comparing AUROCs. A restricted cubic spline demonstrated a strong association between [HDLp1] and CAC incidence. Conclusion The concentration of HDLp1 improves the predictive capacity for the incidence of CAC in diabetic individuals, non-users of statins, without cardiovascular disease.Spline HDLp1 concentration vs CAC incideROC for incident CAC

Causal relationship between sleep apnea and non-alcoholic fatty liver disease: A Mendelian randomization study.

Observational studies indicate that sleep apnea is associated with non-alcoholic fatty liver disease (NAFLD) and its related metabolic features, independent of confounding factors including obesity. However, the causal relationships remain to be determined. Univariable and multivariable Mendelian randomization (MR) analyses were performed to investigate the causal relationship between sleep apnea and NAFLD, along with its typical features including liver function, glycemic traits and lipid profiles. Summary-level data for sleep apnea were obtained from the Finngen consortium (33,423 cases and 307,648 controls). Summary-level data for NAFLD were available from a GWAS meta-analysis (8434 cases and 770,180 controls), and data for 12 NAFLD-related features from corresponding published GWASs. The inverse variance weighted (IVW) analysis was employed as the primary statistical method. Bidirectional MR and CAUSE analysis were conducted to avoid reverse causality and false positive findings. In univariable MR analyses, we found evidence to support a causal effect of genetically predicted sleep apnea on NAFLD (OR = 1.50, 95% CI = 1.18-1.91) and HDL-C (β = -0.045, 95% CI = -0.090 to -0.001). In reverse MR, genetically predicted serum TG was associated with an increased risk of sleep apnea (OR = 1.07, 95% CI = 1.02-1.12), while genetically predicted HDL-C was associated with a decreased risk of sleep apnea (OR = 0.93, 95% CI = 0.89-0.98). After adjusting body mass index or educational attainment, none of these causal associations were retained. However, CAUSE method and MR analyses focusing on lipoprotein subfractions supported a causal effect of sleep apnea on HDL-C and HDL subfractions. This MR study indicated that sleep apnea has no direct causal association with NAFLD, elevated liver enzymes and insulin resistance. Our results showed suggestive inverse associations of genetically predicted sleep apnea on HDL-C and HDL subfractions, indicating that both HDL-C levels and HDL function may be causally implicated in sleep apnea.

Postprandial glycemic and lipidemic effects of black rice anthocyanin extract fortification in foods of varying macronutrient compositions and matrices

Anthocyanin (ACN) fortification of commonly consumed foods is significant as a dietary strategy against the development of metabolic complications by delivering ACNs at high doses. However, its bioactivity and translated metabolic effects in the presence of varying food matrices and macro-constituents is particularly unclear. This end-to-end study investigates the metabolic effects of black rice ACN extract (BRAE) fortification—from in-vitro enzyme inhibitory activities and digestibility, to downstream in vivo impacts on GI, postprandial glycemia and lipidemia. The in vivo effects were investigated in two separate crossover randomised controlled trials (RCT) of 24 healthy participants each—the first RCT determined the postprandial blood glucose, insulin, and ACN bioavailability to a starch-rich single food over 2 h, while the second RCT determined the postprandial blood glucose, insulin, lipid panel, and lipoprotein particles and subfractions to a starch- and fat-rich composite meal over 4 h. In-vitro findings confirmed the inhibitory activities of major black rice ACNs on carbohydrases (p = 0.0004), lipases (p = 0.0002), and starch digestibility (p < 0.0001). in vivo, a 27-point mean GI reduction of wheat bread was observed with BRAE fortification, despite a non-significant attenuation in postprandial glycemia. Conversely, there were no differences in postprandial glycemia when fortified bread was consumed as a composite meal, but acute lipid profiles were altered: (1) improved plasma HDL-c, ([0.0140 mmol/L, 95% CI: (0.00639, 0.0216)], p = 0.0028), Apo-A1 ([0.0296 mmol/L, 95% CI: (0.00757, 0.0515)], p = 0.0203), and Apo-B ([0.00880 mmol/L, 95% CI: (0.00243, 0.0152)], p = 0.0185), (2) modified LDL and HDL subfractions (p < 0.05), and (3) remodelled lipid distributions in HDL and LDL particles. This end-to-end study indicates the potential of ACN fortification in GI reduction and modulating postprandial lipoprotein profiles to starch- and fat-rich composite meals.

Association of HDL subfraction profile with the progression of insulin resistance

Abstract Background Type 2 diabetes mellitus (T2D) is a major global public health problem, as it is associated with increased morbidity, mortality, and healthcare costs. Insulin resistance (IR) is considered to be a condition characterized by disturbances in carbohydrate and lipid metabolisms that precede T2D. The correlation between IR and high-density lipoprotein cholesterol (HDL-C) levels is known, but the underlying mechanisms are not fully understood. The present study aimed to investigate the association between HDL subfraction profile and the development of IR. Methods The progression of IR was assessed using the Homeostatic Model Assessment for IR index (HOMA-IR), and IR was defined as those with a HOMA-IR greater than 3.63. The HDL-C was separated using the Lipoprint system, which identifies ten subfractions (HDL-1-10) and three classes: large- (HDL-L), intermediate- (HDL-I), and small-HDL (HDL-S). All analyses were performed on samples of 240 control subjects and 137 individuals with IR from the Hungarian general and Roma populations. Results The HDL-1 to -6 and the HDL-L and -I showed a significant negative association with elevated HOMA-IR and the presence of IR. Among them, HDL-2 (β = 42.2, p = 4.1 × 10-12) and HDL-L (β = 15.5, p = 2.2 × 10-10) showed the strongest correlation with the IR progression. The optimal cut-off value was found to be 0.264 mmol/L for HDL-L and 0.102 mmol/L and above for HDL-2. The risk of IR is 5.1 times higher for HDL-L levels below the cut-off (p = 2.2 × 10-7), and 4.2 times higher for HDL-2 (p = 3.0 × 10-6). Furthermore, the risk of early manifestation of IR are significantly higher in individuals with both HDL-L (HR = 3.5, p = 3.2 × 10-7) and HDL-2 (HR = 3.19, p = 2.0 × 10-6) levels below the cut-off. Key messages • HDL-2 and -L levels are strongly associated with the development of insulin resistance. • Elevated risk of early onset of insulin resistance is associated with HDL subfraction profile.

Decreased Serum Stromal Cell-Derived Factor-1 in Patients with Familial Hypercholesterolemia and Its Strong Correlation with Lipoprotein Subfractions.

Stromal cell-derived factor-1 (SDF-1) is a chemokine that exerts multifaceted roles in atherosclerosis. However, its association with hyperlipidemia is contradictory. To date, serum SDF-1 and its correlations with lipid fractions and subfractions in heterozygous familial hypercholesterolemia (HeFH) have not been investigated. Eighty-one untreated patients with HeFH and 32 healthy control subjects were enrolled in the study. Serum SDF-1, oxidized LDL (oxLDL) and myeloperoxidase (MPO) were determined by ELISA. Lipoprotein subfractions were detected by Lipoprint. We diagnosed FH using the Dutch Lipid Clinic Network criteria. Significantly lower serum SDF-1 was found in HeFH patients compared to healthy controls. Significant negative correlations were detected between serum total cholesterol, triglycerides, LDL-cholesterol (LDL-C), apolipoprotein B100 (ApoB100) and SDF-1. Furthermore, serum SDF-1 negatively correlated with VLDL and IDL, as well as large LDL and large and intermediate HDL subfractions, while there was a positive correlation between mean LDL-size, small HDL and SDF-1. SDF-1 negatively correlated with oxLDL and MPO. A backward stepwise multiple regression analysis showed that the best predictors of serum SDF-1 were VLDL and oxLDL. The strong correlation of SDF-1 with lipid fractions and subfractions highlights the potential common pathways of SDF-1 and lipoprotein metabolism, which supports the role of SDF-1 in atherogenesis.

An Automatic Fast High Resolution HDL Subfractioning Assay Using Microfluidic Electrophoretic System

Objectives: Studies in recent decade demonstrated the importance of HDL subfractionation in precision medicine. It is notable that not all HDL subfractions are “good” lipoprotein. The lack of a reliable technique that can precisely identify each particle of HDL subfractions remains the major obstacle in clinical application. Based on the principle of microfluidic electrophoresis, we have developed an automatic system (MFE) that meets the need of clinical applications. The objectives of this paper is to test the system for its application, precision, and also the normal range in healthy population using one of major subfraction, HDL-2b, as a target. Methods: The MFE was compared with traditional non-denaturing polyacrylamide gradient gel electrophoresis (GGE). Intra-chip, inter-chip, inter-instrument, inter-lab, and inter-operator precisions were all tested by using the sample in various conditions. An instruction was provided with the instrument and HDL subfractioning kit. Data were analyzed with SPSS for correlation of variation, regressions, etc. Results: The new system exhibited a linear correlation with the traditional GGE system. The intra-chip %CVs, inter-chip %CVs, inter-instrument %CVs of HDL-2b were less than 10%, which was the set acceptance criteria. With 243 samples from healthy individuals demonstrated that the mean value of HDL-2b% is about 25% in both male and female. Conclusions: Our data demonstrated that the MFE system is a fast, automatic, and reliable system that can obtain the percentage of HDL-2b with high precision

B-251 Nmr Lipoproteins Help to Reveal Subphenotypes of Phenoreversion from sars-cov-2 Infection

Abstract Background It is estimated that 10% of patients that suffered from severe acute SARS-CoV-2 infection experience symptoms beyond 3 months post-disease onset. Long COVID is a multisystemic condition that comprises more than 200 symptoms. Common new-onset medical conditions include cardiovascular, type-2 diabetes and chronic fatigue syndrome. Whilst progress has been made in characterising the mechanisms underlying long COVID, supported by similarities with other viral infections, available diagnostics are still insufficient. Molecular phenotyping is an established systems medicine tool that provides an integrative profile of an individual’s biological status that results from the cooperative genomic, transcriptomic and proteomic response to environmental stimuli. It exploits spectroscopic platforms based on nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) to generate precise information on a plethora of molecules that can be modelled to explain specific physiological and pathological conditions. Methods A well characterised longitudinal cohort with &amp;gt;200 SARS-CoV-2 positive individuals was collected in Cambridge Hospitals (2020, Wuhan strain). Each individual was classified according to the severity of its respiratory symptoms ranging from A (asymptomatic) to E (external ventilation). For each sample, cellular and immunological parameters, NMR lipoproteins, amino acid, tryptophan and lipidomics assays were measured. Functional PCA models captured latent dynamics in individual trajectories for C-reactive protein, an established marker of inflammation, and metabolic parameters found to be associated with it. Based on these trends, patient heterogeneity was explored using Gaussian mixture modelling and the resulting stratification was used to train personalised predictors of disease outcome using the first time point after onset as input. The addition of a penalty function during training ensured a parsimonious selection of parameters. Patients were asked to complete surveys months (2–6) after infection. Abundance and co-occurrence of symptoms was assessed using latent factor analysis. Results Linear mixed model regression revealed strong associations between C-reactive protein abundance and molecular parameters. Quinolinic acid, VLDL triglycerides and phospholipids, VLDL and IDL cholesterol and glycoprotein related GlycA are positively correlated, while tryptophan, taurine, indole-3-acetic acid, HDL cholesterol, and phospholipids and the supramolecular phospholipid composite (SPC) peak are strongly anti-correlated. Those findings are congruent with prior work on cohorts from Western Australia and Spain. In both cases, strong lipoprotein signatures were observed; GlycA is increased during acute phase, while SPC and HDL subfraction 4 are strongly depleted. The analysis of individual trajectories measured by CRP and associated parameters revealed 3 groups, mildly affected, good recovery and poor prospect. Patients from the last category showed profoundly altered metabolic profiles even weeks after onset, and a higher co-occurrence of neurological related symptoms. Furthermore, disease outcome scores were predicted for each patient in the early stage of infection. The training of these predictors also distilled a panel of most relevant parameters for that purpose. NMR lipoproteins featured excellent predictive capabilities. Conclusion Broad phenotyping, combined with multi-view multivariate analysis, allowed for robust stratification of COVID-19 patients and accurate personalised prediction of disease outcome. It also confirms the critical role played by lipoprotein metabolism in the immune response that is successfully captured by NMR-base lipoprotein parameters.

Association of HDL Subfraction Profile with the Progression of Insulin Resistance.

Type 2 diabetes mellitus (T2DM) is a major global public health problem, as it is associated with increased morbidity, mortality, and healthcare costs. Insulin resistance (IR) is a condition characterized by disturbances in carbohydrate and lipid metabolism that precedes T2DM. The aim of the present study was to investigate the association between HDL and its subfraction profile and the progression of IR, as assessed by the Homeostatic Model Assessment for IR (HOMA-IR) index, and to define cut-off values to identify an increased risk of IR. Individuals with a HOMA-IR greater than 3.63 were considered to have IR. The HDL subfractions were separated using the Lipoprint system, which identifies ten subfractions (HDL-1-10) in three subclasses as large (HDL-L), intermediate (HDL-I) and small (HDL-S). Analyses were performed on samples from 240 individuals without IR and 137 with IR from the Hungarian general and Roma populations. The HDL-1 to -6 subfractions and the HDL-L and -I classes showed a significant negative association with the progression and existence of IR. Among them, HDL-2 (B = -40.37, p = 2.08 × 10-11) and HDL-L (B = -14.85, p = 9.52 × 10-10) showed the strongest correlation. The optimal threshold was found to be 0.264 mmol/L for HDL-L and 0.102 mmol/L and above for HDL-2. Individuals with HDL-L levels below the reference value had a 5.1-fold higher risk of IR (p = 2.2 × 10-7), while those with HDL-2 levels had a 4.2-fold higher risk (p = 3.0 × 10-6). This study demonstrates that the HDL subfraction profile (especially the decrease in HDL-2 and -L) may be a useful marker for the early detection and intervention of atherogenic dyslipidemia in subjects with impaired glucose and insulin metabolism.

1219-P: HDL Particle Concentration (HDL-P) and Cholesterol Efflux Capacity (CEC) Trajectories Relative to Age at Menopause in Women with Type 1 Diabetes

A previous study in the general population reported adverse changes in the concentration of HDL-P and CEC during the menopausal transition. Similar data do not exist in women with T1D. Moreover, whether changes in HDL metrics over time at a similar age also occur among men, reflecting aging processes, is not well established. We thus quantified HDL-P (calibrated differential ion mobility analysis), total and ABCA1-specific CEC in individuals with T1D and samples available at baseline (or earliest available) and the 25-year follow-up visit of the EDC study (n=155; mean baseline age 27; T1D duration 19 years). Each female participant was age and duration matched (at the time of menopause) to a male participant. Mixed models were constructed to assess the longitudinal trends in HDL-C, HDL subfractions and CEC. Plots were created depicting trajectories of HDL metrics relative to the time of the final menstrual period in women. As shown in the Figure, HDL-C and HDL-P concentrations increased significantly over time in both sexes. In addition, both CEC measures as well as CEC per HDL-P decreased over time in both men and women. Our findings in T1D point to similar trajectories of HDL metrics in men and women (increasing HDL-C and HDL-P but decreasing CEC per HDL-P) suggesting that these changes partially relate to aging and not exclusively to menopause. Disclosure J.Ju: None. R.G.Miller: None. T.J.Orchard: None. T.Costacou: None. Funding National Institutes of Health (R01HL130153, R01DK034818)

Association of CETP Gene Polymorphisms and Haplotypes with Cardiovascular Risk.

Cholesteryl ester transfer protein (CETP) is known to influence HDL-C levels, potentially altering the profile of HDL subfractions and consequently cardiovascular risk (CVR). This study aimed to investigate the effect of five single-nucleotide polymorphisms (SNPs; rs1532624, rs5882, rs708272, rs7499892, and rs9989419) and their haplotypes (H) in the CETP gene on 10-year CVR estimated by the Systematic Coronary Risk Evaluation (SCORE), the Framingham Risk Score for Coronary Heart Disease (FRSCHD) and Cardiovascular Disease (FRSCVD) algorithms. Adjusted linear and logistic regression analyses were used to investigate the association of SNPs and 10 haplotypes (H1-H10) on 368 samples from the Hungarian general and Roma populations. The T allele of rs7499892 showed a significant association with increased CVR estimated by FRS. H5, H7, and H8 showed a significant association with increased CVR based on at least one of the algorithms. The impact of H5 was due to its effect on TG and HDL-C levels, while H7 showed a significant association with FRSCHD and H8 with FRSCVD mediated by a mechanism affecting neither TG nor HDL-C levels. Our results suggest that polymorphisms in the CETP gene may have a significant effect on CVR and that this is not mediated exclusively by their effect on TG and HDL-C levels but also by presently unknown mechanisms.