Design and Baseline Characteristics of STEP-HFpEF Program Evaluating Semaglutide in Patients With Obesity HFpEF Phenotype.

BACKGROUND: The majority of patients with heart failure with preserved ejection fraction (HFpEF) have the obesity phenotype, but no therapies specifically targeting obesity in HFpEF exist. OBJECTIVES: The aim of this study was to describe the design and baseline characteristics of 2 trials of semaglutide, a glucagon-like peptide-1 receptor agonist, in patients with the obesity HFpEF phenotype: STEP-HFpEF (Semaglutide Treatment Effect in People with obesity and HFpEF; NCT04788511) and STEP-HFpEF DM (Semaglutide Treatment Effect in People with obesity and HFpEF and type 2 diabetes; NCT04916470). METHODS: Both STEP-HFpEF and STEP-HFpEF DM are international multicenter, double-blind, placebo-controlled trials that randomized adults with HFpEF and a body mass index ≥30 kg/m2 to once-weekly semaglutide at a dose of 2.4 mg or placebo. Participants were eligible if they had a left ventricular ejection fraction (LVEF) ≥45%; NYHA functional class II to IV; a Kansas City Cardiomyopathy Questionnaire (KCCQ)-Clinical Summary Score (CSS) <90 points; and ≥1 of the following: elevated filling pressures, elevated natriuretic peptides plus structural echocardiographic abnormalities, recent heart failure hospitalization plus ongoing diuretic use, and/or structural abnormalities. The dual primary endpoints are the 52-week change in the KCCQ-CSS and body weight. RESULTS: In STEP-HFpEF and STEP-HFpEF DM (N = 529 and N = 617, respectively), nearly half were women, and most had severe obesity (median body mass index of 37 kg/m2) with typical features of HFpEF (median LVEF of 57%, frequent comorbidities, and elevated natriuretic peptides). Most participants received diuretic agents and renin-angiotensin blockers at baseline, and approximately one-third were on mineralocorticoid receptor antagonists. Sodium-glucose cotransporter-2 inhibitor use was rare in STEP-HFpEF but not in STEP HFpEF DM (32%). Patients in both trials had marked symptomatic and functional impairments (KCCQ-CSS ∼59 points, 6-minute walking distance ∼300 m). CONCLUSIONS: In total, STEP-HFpEF program randomized 1,146 participants with the obesity phenotype of HFpEF and will determine whether semaglutide improves symptoms, physical limitations, and exercise function in addition to weight loss in this vulnerable group.

Correction to: Recognition and Treatment of Homozygous Familial Hypercholesterolemia by Primary Care Physicians: a Survey from the National Lipid Association.

The funding information in this paper was presented incorrectly.

Sudden cardiac death in families with premature cardiovascular disease.

OBJECTIVE: Sudden cardiac death (SCD) in families with premature atherosclerosis (PAS) is generally attributed to lethal arrhythmias during myocardial infarction. Yet, such arrhythmias may also arise from non-ischaemic inherited susceptibility. We aimed to test the hypothesis that Brugada syndrome is prevalent among families with PAS in which SCD occurred. METHODS: We investigated all patients who underwent Ajmaline testing to screen them for Brugada syndrome because of unexplained familial SCD in the Amsterdam University Medical Centers between 2004 and 2017. We divided the cohort into two groups based on a positive family history for PAS. All individuals with a positive Ajmaline test were screened for SCN5A-mutation. RESULTS: In families with SCD and PAS, the prevalence of positive Ajmaline test was similar to families with SCD alone (22% vs 19%). The number of SCD cases in families with SCD and PAS was higher (2.34 vs 1.63, p<0.001) and SCD occurred at older age in families with SCD and PAS (42 years vs 36 years, p<0.001), while the prevalence of SCN5A mutations was lower (3% vs 18%, p<0.05). CONCLUSIONS: Brugada syndrome has a similar prevalence in families with SCD and PAS as in families with SCD alone, although SCD in families with SCD and PAS occurs in more family members and at older age, while SCN5A mutations in these families are rare. This suggests that the SCD occurring in families with PAS could be related to an underlying genetic predisposition of arrhythmias, with a different genetic origin. It could be considered to screen families with SCD and PAS for Brugada syndrome.

Phenome-wide association analysis of LDL-cholesterol lowering genetic variants in PCSK9.

BACKGROUND: We characterised the phenotypic consequence of genetic variation at the PCSK9 locus and compared findings with recent trials of pharmacological inhibitors of PCSK9. METHODS: Published and individual participant level data (300,000+ participants) were combined to construct a weighted PCSK9 gene-centric score (GS). Seventeen randomized placebo controlled PCSK9 inhibitor trials were included, providing data on 79,578 participants. Results were scaled to a one mmol/L lower LDL-C concentration. RESULTS: The PCSK9 GS (comprising 4 SNPs) associations with plasma lipid and apolipoprotein levels were consistent in direction with treatment effects. The GS odds ratio (OR) for myocardial infarction (MI) was 0.53 (95% CI 0.42; 0.68), compared to a PCSK9 inhibitor effect of 0.90 (95% CI 0.86; 0.93). For ischemic stroke ORs were 0.84 (95% CI 0.57; 1.22) for the GS, compared to 0.85 (95% CI 0.78; 0.93) in the drug trials. ORs with type 2 diabetes mellitus (T2DM) were 1.29 (95% CI 1.11; 1.50) for the GS, as compared to 1.00 (95% CI 0.96; 1.04) for incident T2DM in PCSK9 inhibitor trials. No genetic associations were observed for cancer, heart failure, atrial fibrillation, chronic obstructive pulmonary disease, or Alzheimer's disease - outcomes for which large-scale trial data were unavailable. CONCLUSIONS: Genetic variation at the PCSK9 locus recapitulates the effects of therapeutic inhibition of PCSK9 on major blood lipid fractions and MI. While indicating an increased risk of T2DM, no other possible safety concerns were shown; although precision was moderate.

Naturally Occurring Variants in LRP1 (Low-Density Lipoprotein Receptor-Related Protein 1) Affect HDL (High-Density Lipoprotein) Metabolism Through ABCA1 (ATP-Binding Cassette A1) and SR-B1 (Scavenger Receptor Class B Type 1) in Humans.

OBJECTIVE: Studies into the role of LRP1 (low-density lipoprotein receptor-related protein 1) in human lipid metabolism are scarce. Although it is known that a common variant in LRP1 (rs116133520) is significantly associated with HDL-C (high-density lipoprotein cholesterol), the mechanism underlying this observation is unclear. In this study, we set out to study the functional effects of 2 rare LRP1 variants identified in subjects with extremely low HDL-C levels. APPROACH AND RESULTS: In 2 subjects with HDL-C below the first percentile for age and sex and moderately elevated triglycerides, we identified 2 rare variants in LRP1: p.Val3244Ile and p.Glu3983Asp. Both variants decrease LRP1 expression and stability. We show in a series of translational experiments that these variants culminate in reduced trafficking of ABCA1 (ATP-binding cassette A1) to the cell membrane. This is accompanied by an increase in cell surface expression of SR-B1 (scavenger receptor class B type 1). Combined these effects may contribute to low HDL-C levels in our study subjects. Supporting these findings, we provide epidemiological evidence that rs116133520 is associated with apo (apolipoprotein) A1 but not with apoB levels. CONCLUSIONS: This study provides the first evidence that rare variants in LRP1 are associated with changes in human lipid metabolism. Specifically, this study shows that LRP1 may affect HDL metabolism by virtue of its effect on both ABCA1 and SR-B1.

Lysosomal Cholesterol Hydrolysis Couples Efferocytosis to Anti-Inflammatory Oxysterol Production.

RATIONALE: Macrophages face a substantial amount of cholesterol after the ingestion of apoptotic cells, and the LIPA (lysosomal acid lipase) has a major role in hydrolyzing cholesteryl esters in the endocytic compartment. OBJECTIVE: Here, we directly investigated the role of LIPA-mediated clearance of apoptotic cells both in vitro and in vivo. METHODS AND RESULTS: We show that LIPA inhibition causes a defective efferocytic response because of impaired generation of 25-hydroxycholesterol and 27-hydroxycholesterol. Reduced synthesis of 25-hydroxycholesterol after LIPA inhibition contributed to defective mitochondria-associated membrane leading to mitochondrial oxidative stress-induced NLRP3 (NOD-like receptor family, pyrin domain containing) inflammasome activation and caspase-1-dependent Rac1 (Ras-related C3 botulinum toxin substrate 1) degradation. A secondary event consisting of failure to appropriately activate liver X receptor-mediated pathways led to mitigation of cholesterol efflux and apoptotic cell clearance. In mice, LIPA inhibition caused defective clearance of apoptotic lymphocytes and stressed erythrocytes by hepatic and splenic macrophages, culminating in splenomegaly and splenic iron accumulation under hypercholesterolemia. CONCLUSIONS: Our findings position lysosomal cholesterol hydrolysis as a critical process that prevents metabolic inflammation by enabling efficient macrophage apoptotic cell clearance.

The effect of lomitapide on cardiovascular outcome measures in homozygous familial hypercholesterolemia: A modelling analysis.

Background Patients with homozygous familial hypercholesterolemia are at high risk of cardiovascular disease due to high low-density lipoprotein (LDL)-cholesterol levels. Cardiovascular disease outcome studies are impossible to conduct, due to the rarity of homozygous familial hypercholesterolemia. We modelled the potential efficacy of lomitapide, a microsomal transfer protein inhibitor, on major adverse cardiovascular events (MACEs) and survival. Design We calculated the effect on cardiovascular outcomes of a 38% plasma LDL-cholesterol reduction induced by lomitapide. Methods Age-dependent hazards and treatment-dependent hazard ratios for mortality and time to first MACE were calculated from an observational study of 149 South African homozygous familial hypercholesterolemia patients. Cardiovascular-related mortality hazards were derived by adjusting for general population non-cardiovascular-related mortality. For every mmol/L LDL-cholesterol reduction, a relative risk reductions of 23% (mortality) and 15% (major adverse cardiovascular events) were observed. Results For the most robust model, baseline median survival with current treatments (LDL-cholesterol 8.7 mmol/L) was 48 years. In the survival benefit analysis, starting lomitapide at age 18 years and reducing LDL-cholesterol by 3.3 mmol/L from baseline would increase life expectancy by 11.2 years and delay the time to first MACE by 5.7 years. Analysis suggested lifetime lomitapide treatment could increase median life expectancy by 11.7 years and time to first MACE by 6.7 years. Conclusion Our modelling analyses show that additional LDL-cholesterol lowering by lomitapide may increase life expectancy in patients with homozygous familial hypercholesterolemia. Further clinical studies are warranted to determine the cardiovascular morbidity and mortality benefits of lomitapide.

Proprotein Convertase Subtilisin Kexin Type 9 Inhibition for Autosomal Recessive Hypercholesterolemia-Brief Report.

OBJECTIVE: Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors lower low-density lipoprotein (LDL) cholesterol in the vast majority of patients with autosomal dominant familial hypercholesterolemia. Will PCSK9 inhibition with monoclonal antibodies, in particular alirocumab, be of therapeutic value for patients with autosomal recessive hypercholesterolemia (ARH)? APPROACH AND RESULTS: Primary lymphocytes were obtained from 28 genetically characterized ARH patients and 11 controls. ARH lymphocytes treated with mevastatin were incubated with increasing doses of recombinant PCSK9 with or without saturating concentrations of alirocumab. Cell surface LDL receptor expression measured by flow cytometry and confocal microscopy was higher in ARH than in control lymphocytes. PCSK9 significantly reduced LDL receptor expression in ARH lymphocytes albeit to a lower extent than in control lymphocytes (25% versus 76%, respectively), an effect reversed by alirocumab. Fluorescent LDL cellular uptake, also measured by flow cytometry, was reduced in ARH lymphocytes compared with control lymphocytes. PCSK9 significantly lowered LDL cellular uptake in ARH lymphocytes, on average by 18%, compared with a 46% reduction observed in control lymphocytes, an effect also reversed by alirocumab. Overall, the effects of recombinant PCSK9, and hence of alirocumab, on LDL receptor expression and function were significantly less pronounced in ARH than in control cells. CONCLUSIONS: PCSK9 inhibition with alirocumab on top of statin treatment has the potential to lower LDL cholesterol in some autosomal recessive hypercholesterolemia patients.

Lipoprotein profiles in human heterozygote carriers of a functional mutation P297S in scavenger receptor class B1.

The scavenger receptor class B type 1 (SR-B1) is an important HDL receptor involved in cholesterol uptake and efflux, but its physiological role in human lipoprotein metabolism is not fully understood. Heterozygous carriers of the SR-B1(P297S) mutation are characterized by increased HDL cholesterol levels, impaired cholesterol efflux from macrophages and attenuated adrenal function. Here, the composition and function of lipoproteins were studied in SR-B1(P297S) heterozygotes.Lipoproteins from six SR-B1(P297S) carriers and six family controls were investigated. HDL and LDL/VLDL were isolated by ultracentrifugation and proteins were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. HDL antioxidant properties, paraoxonase 1 activities, apoA-I methionine oxidations and HDL cholesterol efflux capacity were assessed.Multivariate modeling separated carriers from controls based on lipoprotein composition. Protein analyses showed a significant enrichment of apoE in LDL/VLDL and of apoL-1 in HDL from heterozygotes compared to controls. The relative distribution of plasma apoE was increased in LDL and in lipid-free form. There were no significant differences in paraoxonase 1 activities, HDL antioxidant properties or HDL cholesterol efflux capacity but heterozygotes showed a significant increase of oxidized methionines in apoA-I.The SR-B1(P297S) mutation affects both HDL and LDL/VLDL protein compositions. The increase of apoE in carriers suggests a compensatory mechanism for attenuated SR-B1 mediated cholesterol uptake by HDL. Increased methionine oxidation may affect HDL function by reducing apoA-I binding to its targets. The results illustrate the complexity of lipoprotein metabolism that has to be taken into account in future therapeutic strategies aiming at targeting SR-B1.

Association of exome sequences with plasma C-reactive protein levels in >9000 participants.

C-reactive protein (CRP) concentration is a heritable systemic marker of inflammation that is associated with cardiovascular disease risk. Genome-wide association studies have identified CRP-associated common variants associated in ∼25 genes. Our aims were to apply exome sequencing to (1) assess whether the candidate loci contain rare coding variants associated with CRP levels and (2) perform an exome-wide search for rare variants in novel genes associated with CRP levels. We exome-sequenced 6050 European-Americans (EAs) and 3109 African-Americans (AAs) from the NHLBI-ESP and the CHARGE consortia, and performed association tests of sequence data with measured CRP levels. In single-variant tests across candidate loci, a novel rare (minor allele frequency = 0.16%) CRP-coding variant (rs77832441-A; p.Thr59Met) was associated with 53% lower mean CRP levels (P = 2.9 × 10(-6)). We replicated the association of rs77832441 in an exome array analysis of 11 414 EAs (P = 3.0 × 10(-15)). Despite a strong effect on CRP levels, rs77832441 was not associated with inflammation-related phenotypes including coronary heart disease. We also found evidence for an AA-specific association of APOE-ε2 rs7214 with higher CRP levels. At the exome-wide significance level (P < 5.0 × 10(-8)), we confirmed associations for reported common variants of HNF1A, CRP, IL6R and TOMM40-APOE. In gene-based tests, a burden of rare/lower frequency variation in CRP in EAs (P ≤ 6.8 × 10(-4)) and in retinoic acid receptor-related orphan receptor α (RORA) in AAs (P = 1.7 × 10(-3)) were associated with CRP levels at the candidate gene level (P < 2.0 × 10(-3)). This inquiry did not elucidate novel genes, but instead demonstrated that variants distributed across the allele frequency spectrum within candidate genes contribute to CRP levels.

Lysosomal acid lipase deficiency--an under-recognized cause of dyslipidaemia and liver dysfunction.

Lysosomal acid lipase deficiency (LAL-D) is a rare autosomal recessive lysosomal storage disease caused by deleterious mutations in the LIPA gene. The age at onset and rate of progression vary greatly and this may relate to the nature of the underlying mutations. Patients presenting in infancy have the most rapidly progressive disease, developing signs and symptoms in the first weeks of life and rarely surviving beyond 6 months of age. Children and adults typically present with some combination of dyslipidaemia, hepatomegaly, elevated transaminases, and microvesicular hepatosteatosis on biopsy. Liver damage with progression to fibrosis, cirrhosis and liver failure occurs in a large proportion of patients. Elevated low-density lipoprotein cholesterol levels and decreased high-density lipoprotein cholesterol levels are common features, and cardiovascular disease may manifest as early as childhood. Given that these clinical manifestations are shared with other cardiovascular, liver and metabolic diseases, it is not surprising that LAL-D is under-recognized in clinical practice. This article provides practical guidance to lipidologists, endocrinologists, cardiologists and hepatologists on how to recognize individuals with this life-limiting disease. A diagnostic algorithm is proposed with a view to achieving definitive diagnosis using a recently developed blood test for lysosomal acid lipase. Finally, current management options are reviewed in light of the ongoing development of enzyme replacement therapy with sebelipase alfa (Synageva BioPharma Corp., Lexington, MA, USA), a recombinant human lysosomal acid lipase enzyme.

ApoA-I mutations, L202P and K131del, in HDL from heterozygotes with low HDL-C.

PURPOSE: Mutations in apolipoprotein A-I (apoA-I) may affect plasma high-density lipoprotein (HDL) cholesterol levels and the risk for cardiovascular disease but little is known about the presence and effects of circulating apoA-I variants. This study investigates whether the apoA-I mutations, apoA-I(L202P) and apoA-I(K131del) , are present on plasma HDL particles derived from heterozygote carriers and whether this is associated to changes in HDL protein composition. EXPERIMENTAL DESIGN: Plasma HDL of heterozygotes for either apoA-I(L202P) or apoA-I(K131del) and family controls was isolated using ultracentrifugation. HDL proteins were separated by 2DE and analyzed by MS. RESULTS: ApoA-I peptides containing apoA-I(L202P) or apoA-I(K131del) were identified in HDL from heterozygotes. The apoA-I(L202P) mutant peptide was less abundant than wild-type peptide while the apoA-I(K131del) mutant peptide was more abundant than wild-type peptide in the heterozygotes. Two-dimensional gel electrophoresis analyses indicated that, compared to controls, HDL in apoA-I(L202P) carriers contained less apoE and more zinc-α-2-glycoprotein while HDL from the apoA-I(K131del) heterozygotes contained more alpha-1-antitrypsin and transthyretin. CONCLUSIONS AND CLINICAL RELEVANCE: Both apoA-I(L202P) and apoA-I(K131del) were identified in HDL. In heterozygotes, these mutations have markedly differential effects on the concentration of wild-type apoA-I in the circulation, as well as the HDL proteome, both of which might affect the clinical phenotype encountered in the heterozygous carriers.

Efficacy and safety of mipomersen sodium (Kynamro).

INTRODUCTION: Mipomersen is a first-in-class drug indicated as an adjunct to lipid-lowering medications and diet to reduce low-density lipoprotein-cholesterol (LDL-C), apolipoprotein B (apoB), total cholesterol (TC) and non-high density lipoprotein-cholesterol (non-HDL-C) in patients with homozygous familial hypercholesterolemia (HoFH). AREAS COVERED: This article summarizes the efficacy and safety profile of mipomersen based on literature, public materials available from the Endocrinologic and Metabolic Drugs Advisory Committee meeting (FDA) in review of the New Drug Application (NDA 203568) and the recent product label. EXPERT OPINION: Patients suffering from HoFH are characterized by elevated levels of LDL-C and are, therefore, at severely increased risk for cardiovascular disease (CVD). Currently available lipid-lowering therapies (LLT), such as statins, have been shown to lower LDL-C levels and CVD risk. However, in patients suffering from HoFH, additional therapy is urgently needed to further decrease LDL-C levels and CVD risk. Mipomersen (Kynamro) has recently been approved by the FDA as a novel LLT modality in patients with HoFH. Mipomersen has been show to result in highly relevant absolute LDL-C reductions in HoFH patients, and given the undisputed causal relationship between LDL-C levels and CVD risk, this additional LDL-C lowering is expected to result in a robust CVD risk reduction.

The impact of partial and complete loss-of-function mutations in endothelial lipase on high-density lipoprotein levels and functionality in humans.

BACKGROUND: Endothelial lipase is a phospholipase with activity against high-density lipoprotein. Although a small number of mutations in LIPG have been described, the role of LIPG in protection against atherosclerosis is unclear. METHODS AND RESULTS: We identified 8 loss-of-function (LOF) mutations in LIPG in individuals with high-density lipoprotein cholesterol. Functional analysis confirmed that most rare mutations abolish lipase activity in vitro, indicating complete LOF, whereas 2 more common mutations N396S and R476W reduce activity by ≈50%, indicating partial LOF and implying ≈50% and ≈75% remaining endothelial lipase function in heterozygous complete LOF and partial LOF mutation carriers, respectively. complete LOF mutation carriers had significantly higher plasma high-density lipoprotein cholesterol levels compared with partial LOF mutation carriers. Apolipoprotein B-depleted serum from complete LOF carriers showed significantly enhanced cholesterol efflux acceptor capacity, whereas only trends were observed in partial LOF carriers. Carriers of LIPG mutations exhibited trends toward reduced coronary artery disease in 4 independent cohorts (meta-analysis odds ratio, 0.7; P=0.04). CONCLUSIONS: Our data suggest that the impact of LIPG mutations is directly related to their effect on endothelial lipase function and support that antagonism of endothelial lipase function improves cardioprotection.

Monocyte gene expression signature of patients with early onset coronary artery disease.

The burden of cardiovascular disease (CVD) cannot be fully addressed by therapy targeting known pathophysiological pathways. Even with stringent control of all risk factors CVD events are only diminished by half. A number of additional pathways probably play a role in the development of CVD and might serve as novel therapeutic targets. Genome wide expression studies represent a powerful tool to identify such novel pathways. We compared the expression profiles in monocytes from twenty two young male patients with premature familial CAD with those from controls matched for age, sex and smoking status, without a family history of CVD. Since all patients were on statins and aspirin treatment, potentially affecting the expression of genes in monocytes, twelve controls were subsequently treated with simvastatin and aspirin for 6 and 2 weeks, respectively. By whole genome expression arrays six genes were identified to have differential expression in the monocytes of patients versus controls; ABCA1, ABCG1 and RGS1 were downregulated in patients, whereas ADRB2, FOLR3 and GSTM1 were upregulated. Differential expression of all genes, apart from GSTM1, was confirmed by qPCR. Aspirin and statins altered gene expression of ABCG1 and ADBR2. All finding were validated in a second group of twenty four patients and controls. Differential expression of ABCA1, RSG1 and ADBR2 was replicated. In conclusion, we identified these 3 genes to be expressed differently in CAD cases which might play a role in the pathogenesis of atherosclerotic vascular disease.

Truncation mutations in ABCA1 suppress normal upregulation of full-length ABCA1 by 9-cis-retinoic acid and 22-R-hydroxycholesterol.

Mutations in ABCA1 uniformly decrease plasma HDL-cholesterol (HDL-C) and reduce cholesterol efflux, yet different mutations in ABCA1 result in different phenotypic effects in heterozygotes. For example, truncation mutations result in significantly lower HDL-C and apoliprotein A-I (apoA-I) levels in heterozygotes compared with nontruncation mutations, suggesting that truncation mutations may negatively affect the wild-type allele. To specifically test this hypothesis, we examined ABCA1 protein expression in response to 9-cis-retinoic acid (9-cis-RA) and 22-R-hydroxycholesterol (22-R-OH-Chol) in a collection of human fibroblasts representing eight different mutations and observed that truncation mutations blunted the response to oxysterol stimulation and dominantly suppressed induction of the remaining full-length allele to 5-10% of wild-type levels. mRNA levels between truncation and nontruncation mutations were comparable, suggesting that ABCA1 expression was suppressed at the protein level. Dominant negative activity of truncated ABCA1 was recapitulated in an in vitro model using transfected Cos-7 cells. Our results suggest that the severe reduction of HDL-C in patients with truncation mutations may be at least partly explained by dominant negative suppression of expression and activity of the remaining full-length ABCA1 allele. These data suggest that ABCA1 requires a physical association with itself or other molecules for normal function and has important pharmacogenetic implications for individuals with truncation mutations.