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ObjectiveLipoprotein(a) (Lp(a)) is an important genetically determined risk factor for atherosclerotic vascular disease (ASCVD). With the development of Lp(a)-lowering therapies, this study sought to characterise patterns of Lp(a) levels in a global ASCVD population and identify racial, ethnic, regional and gender differences.MethodsA multicentre cross-sectional epidemiological study to estimate the prevalence of elevated Lp(a) in patients with a history of myocardial infarction, ischaemic stroke or peripheral artery disease conducted at 949 sites in 48 countries in North America, Europe, Asia, South America, South Africa and Australia between April 2019 and July 2021. Low-density lipoprotein cholesterol (LDL-C) and Lp(a) levels were measured either as mass (mg/dL) or molar concentration (nmol/L).ResultsOf 48 135 enrolled patients, 13.9% had prior measurements of Lp(a). Mean age was 62.6 (SD 10.1) years and 25.9% were female. Median Lp(a) was 18.0 mg/dL (IQR 7.9–57.1) or 42.0 nmol/L (IQR 15.0–155.4). Median LDL-C was 77 mg/dL (IQR 58.4–101.0). Lp(a) in women was higher, 22.8 (IQR 9.0–73.0) mg/dL, than in men, 17.0 (IQR 7.1–52.2) mg/dL, p50 mg/dL, 20.7% had levels >70 mg/dL, 12.9% were >90 mg/dL and 26.0% of patients exceeded 150 nmol/L.ConclusionsGlobally, Lp(a) is measured in a small minority of patients with ASCVD and is highest in black, younger and female patients. More than 25% of patients had levels exceeding the established threshold for increased cardiovascular risk, approximately 50 mg/dL or 125 nmol/L.Trial registration number

Background and aims Infusion of high-density lipoprotein (HDL) mimetics failed to induce regression of atherosclerosis in recent randomized clinical trials. However, patients in these previous trials had normal levels of HDL-cholesterol, which potentially limited efficacy. Patients with very low levels of HDL-cholesterol and impaired cholesterol efflux capacity can be expected to derive the most potential benefit from infusion of HDL mimetics. This randomized clinical trial evaluated the efficacy of infusions of the HDL mimetic CER-001 in patients with genetically determined very low levels of HDL cholesterol. Methods In this multicenter, randomized clinical trial, we recruited patients with familial hypoalphalipoproteinemia (due to ABCA1 and/or APOA1 loss-of-function variants). Participants were randomized to intravenous infusions of 8 mg/kg CER-001 or placebo (2:1 ratio), comprising 9 weekly infusions followed by infusions every two weeks. Patients underwent repeated 3T-MRI to assess mean vessel wall area and 18F-FDG PET/CT to quantify arterial wall inflammation. Results A total of 30 patients with a mean age of 52.7 ± 7.4 years and HDL-cholesterol of 0.35 ± 0.25 mmol/L were recruited. After 24 weeks, the absolute change in mean vessel wall area was not significantly different in the CER-001 group compared with placebo (n = 27; treatment difference: 0.77 mm2, p = 0.21). Furthermore, there was no significant difference in carotid arterial wall inflammation (n = 24, treatment difference: 0.10 target-to-background ratio of the most diseased segment, p = 0.33) after 24 weeks. Conclusion In patients with genetically determined very low HDL-cholesterol, 24 weeks of treatment with HDL mimetic CER-001 did not reduce carotid vessel wall dimensions or arterial wall inflammation, compared with placebo.

Background High-density lipoprotein cholesterol (HDL-C) concentration is inversely related to risk of major adverse cardiovascular events (MACE) in epidemiologic studies but is a poorer predictor of MACE in patients with established coronary heart disease. HDL particle concentration (HDLP) has been proposed as a better predictor of risk. We investigated whether HDLP is associated with risk of MACE after acute coronary syndrome (ACS). Methods The dal-Outcomes trial compared the CETP inhibitor dalcetrapib with placebo in patients with recent ACS. In a nested case-cohort analysis, total, large, medium, and small HDLPs were measured by nuclear magnetic resonance spectroscopy at baseline (4-12 weeks after ACS) in 476 cases with MACE and 902 controls. Hazard ratios (HRs; case-control) for 1-SD increment of HDLP or HDL-C at baseline were calculated with and without adjustment for demographic, clinical, laboratory, and treatment variables. Similarly, HRs for MACE were calculated for changes in HDLP or HDL-C from baseline to month 3 of assigned treatment. Results Over median follow-up of 28 months, the risk of MACE was not associated with baseline HDLP (adjusted HR = 0.98, 95% CI = 0.84-1.15, P = .81), any HDLP subclass, or HDL-C. Dalcetrapib increased HDL-C and total, medium, and large HDLP and decreased small HDLP but had no effect on MACE compared with placebo. There were no association of risk of MACE with change in HDLP or HDL-C and no interaction with assigned study treatment. Conclusions Neither baseline HDLP nor the change in HDLP on treatment with dalcetrapib or placebo was associated with risk of MACE after ACS.

[Background]: Homozygous familial hypercholesterolaemia (HoFH) is a rare inherited disorder resulting in extremely elevated low-density lipoprotein cholesterol levels and premature atherosclerotic cardiovascular disease (ASCVD). Current guidance about its management and prognosis stems from small studies, mostly from high-income countries. The objective of this study was to assess the clinical and genetic characteristics, as well as the impact, of current practice on health outcomes of HoFH patients globally., [Methods]: The HoFH International Clinical Collaborators registry collected data on patients with a clinical, or genetic, or both, diagnosis of HoFH using a retrospective cohort study design. This trial is registered with ClinicalTrials.gov, NCT04815005., [Findings]: Overall, 751 patients from 38 countries were included, with 565 (75%) reporting biallelic pathogenic variants. The median age of diagnosis was 12∙0 years (IQR 5∙5–27∙0) years. Of the 751 patients, 389 (52%) were female and 362 (48%) were male. Race was reported for 527 patients; 338 (64%) patients were White, 121 (23%) were Asian, and 68 (13%) were Black or mixed race. The major manifestations of ASCVD or aortic stenosis were already present in 65 (9%) of patients at diagnosis of HoFH. Globally, pretreatment LDL cholesterol levels were 14∙7 mmol/L (IQR 11∙6–18∙4). Among patients with detailed therapeutic information, 491 (92%) of 534 received statins, 342 (64%) of 534 received ezetimibe, and 243 (39%) of 621 received lipoprotein apheresis. On-treatment LDL cholesterol levels were lower in high-income countries (3∙93 mmol/L, IQR 2∙6–5∙8) versus non-highincome countries (9∙3 mmol/L, 6∙7–12∙7), with greater use of three or more lipid-lowering therapies (LLT; highincome 66% vs non-high-income 24%) and consequently more patients attaining guideline-recommended LDL cholesterol goals (high-income 21% vs non-high-income 3%). A first major adverse cardiovascular event occurred a decade earlier in non-high-income countries, at a median age of 24∙5 years (IQR 17∙0–34∙5) versus 37∙0 years (29∙0–49∙0) in high-income countries (adjusted hazard ratio 1∙64, 95% CI 1∙13–2∙38)., [Interpretation]: Worldwide, patients with HoFH are diagnosed too late, undertreated, and at high premature ASCVD risk. Greater use of multi-LLT regimens is associated with lower LDL cholesterol levels and better outcomes. Significant global disparities exist in treatment regimens, control of LDL cholesterol levels, and cardiovascular event-free survival, which demands a critical re-evaluation of global health policy to reduce inequalities and improve outcomes for all patients with HoFH., Amsterdam University Medical Centers, Location Academic Medical Center; Perelman School of Medicine at the University of Pennsylvania; and European Atherosclerosis Society

Background The European Atherosclerosis Society Familial Hypercholesterolaemia Studies Collaboration (FHSC) global registry provides a platform for the global surveillance of familial hypercholesterolaemia through harmonisation and pooling of multinational data. In this study, we aimed to characterise the adult population with heterozygous familial hypercholesterolaemia and described how it is detected and managed globally. Methods Using FHSC global registry data, we did a cross-sectional assessment of adults (aged 18 years or older) with a clinical or genetic diagnosis of probable or definite heterozygous familial hypercholesterolaemia at the time they were entered into the registries. Data were assessed overall and by WHO regions, sex, and index versus non-index cases. Findings Of the 61 612 individuals in the registry, 42 167 adults (21 999 [53.6%] women) from 56 countries were included in the study. Of these, 31 798 (75.4%) were diagnosed with the Dutch Lipid Clinic Network criteria, and 35 490 (84.2%) were from the WHO region of Europe. Median age of participants at entry in the registry was 46.2 years (IQR 34.3-58.0); median age at diagnosis of familial hypercholesterolaemia was 44.4 years (32.5-56.5), with 40.2% of participants younger than 40 years when diagnosed. Prevalence of cardiovascular risk factors increased progressively with age and varied by WHO region. Prevalence of coronary disease was 17.4% (2.1% for stroke and 5.2% for peripheral artery disease), increasing with concentrations of untreated LDL cholesterol, and was about two times lower in women than in men. Among patients receiving lipid-lowering medications, 16 803 (81.1%) were receiving statins and 3691 (21.2%) were on combination therapy, with greater use of more potent lipid-lowering medication in men than in women. Median LDL cholesterol was 5.43 mmol/L (IQR 4.32-6.72) among patients not taking lipid-lowering medications and 4.23 mmol/L (3.20-5.66) among those taking them. Among patients taking lipid-lowering medications, 2.7% had LDL cholesterol lower than 1.8 mmol/L; the use of combination therapy, particularly with three drugs and with proprotein convertase subtilisin-kexin type 9 inhibitors, was associated with a higher proportion and greater odds of having LDL cholesterol lower than 1.8 mmol/L. Compared with index cases, patients who were non-index cases were younger, with lower LDL cholesterol and lower prevalence of cardiovascular risk factors and cardiovascular diseases (all p, Pfizer Independent Grant for Learning Change [16157823]; Amgen; Merck Sharp Dohme; Sanofi-Aventis; Daiichi Sankyo; Regeneron; National Institute for Health Research (NIHR) Imperial Biomedical Research Centre, UK; NIHR; Czech Ministry of Health [NU20-02-00261]; Canadian Institutes of Health Research; Austrian Heart Foundation; Tyrolean Regional Government; Gulf Heart Association, The EAS FHSC is an academic initiative that has received funding from a Pfizer Independent Grant for Learning & Change 2014 (16157823) and from investigator-initiated research grants to the European Atherosclerosis Society-Imperial College London from Amgen, Merck Sharp & Dohme, Sanofi-Aventis, Daiichi Sankyo, and Regeneron. KKR acknowledges support from the National Institute for Health Research (NIHR) Imperial Biomedical Research Centre, UK. KID acknowledges support from a PhD Studentship from NIHR under the Applied Health Research programme for Northwest London, UK (the views expressed in this publication are those of the authors and not necessarily those of the National Health Service, the NIHR, or the Department of Health). TF was supported by a grant from the Czech Ministry of Health (NU20-02-00261). JG receives support from the Canadian Institutes of Health Research. The Austrian Familial Hypercholesterolaemia registry has been supported by funds from the Austrian Heart Foundation and the Tyrolean Regional Government. The Gulf Familial Hypercholesterolaemia registry was done under the auspices of the Gulf Heart Association.

Patients with familial hyperparathyroidism and low urinary calcium excretion may have familial hypocalciuric hypercalcemia (FHH) with mutations in one of three genes: the calcium-sensing receptor (CaSR) defining FHH-type 1, the adaptor-related protein complex 2 (AP2S1) related to FHH-type 3 or the G-protein subunit alpha11 (GNA11) associated with FHH-type 2. We aimed to evaluate the presence of mutations in these genes and to identify phenotypic specificities and differences in these patients. Selected patients were recruited for genetic evaluation. After informed consent was signed, blood for DNA extraction was obtained and genetic sequencing of CaSR was done. In negative cases, we further performed sequencing of AP2S1 and GNA11. A total of 10 index cases were recruited. CaSR sequencing yielded three missense heterozygous mutations (30%): c.554G > A (p.I32V) previously characterized by our team, c.1394 G > A (p.R465Q) and a novel expected disease-causing mutation c.2479 A > C (p.S827R). We identified 2 additional patients (20%) carrying the deleterious recurrent mutation c.44G > T (p.R15L) in the AP2S1 gene. No GNA11 mutation was found. Clinically, patients with AP2S1 mutations had significant cognitive and behavioral disorders, and higher blood calcium and magnesium levels than patients with FHH1. CaSR and AP2S1 sequencing is worthwhile in patients with familial hyperparathyroidism and phenotype suggesting FHH as it can diagnose up to 50% of cases. GNA11 mutations seem much rarer. Learning disabilities in these patients, associated with higher serum calcium and magnesium levels may suggest the presence of AP2S1 rather than CaSR mutation and may guide the first step in the genetic evaluation.

Ismail et al. show that 27-hydroxycholesterol, a peripheral cholesterol metabolite capable of passing the blood–brain barrier, reduces brain glucose uptake by upregulating the renin-angiotensin system and inhibiting GLUT4. This alteration affects memory processes and is likely to have implications on neurodegenerative diseases., Hypercholesterolemia is associated with cognitively deteriorated states. Here, we show that excess 27-hydroxycholesterol (27-OH), a cholesterol metabolite passing from the circulation into the brain, reduced in vivo brain glucose uptake, GLUT4 expression, and spatial memory. Furthermore, patients exhibiting higher 27-OH levels had reduced 18F-fluorodeoxyglucose uptake. This interplay between 27-OH and glucose uptake revealed the engagement of the insulin-regulated aminopeptidase (IRAP). 27-OH increased the levels and activity of IRAP, countered the IRAP antagonist angiotensin IV (AngIV)–mediated glucose uptake, and enhanced the levels of the AngIV-degrading enzyme aminopeptidase N (AP-N). These effects were mediated by liver X receptors. Our results reveal a molecular link between cholesterol, brain glucose, and the brain renin-angiotensin system, all of which are affected in some neurodegenerative diseases. Thus, reducing 27-OH levels or inhibiting AP-N maybe a useful strategy in the prevention of the altered glucose metabolism and memory decline in these disorders.

Objective Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by mutations in the genes for LDL receptor (LDLR), apolipoprotein B (APOB) and Proprotein convertase subtilisin/kexin type9 (PCSK9). The purpose of the current investigation was to define the current spectrum of mutations causing FH in Israel. Methods New families were collected through the MEDPED (Make Early Diagnosis Prevent Early Death) FH program. Molecular analysis of the LDLR, PCSK9 and APOB genes were done using High Resolution Melt and direct sequencing in 67 index cases. A 6-SNP LDL-C gene score calculation for polygenic hypercholesterolaemia was done using TaqMan genotyping. Results Mean serum cholesterol was 7.48±1.89mmol/L and the mean serum LDL-C was 5.99±1.89mmol/L. Mutations in the LDLR and APOB gene were found in 24 cases (35.8%), with 16 in LDLR, none in PCSK9 and one, p.(R3527Q) in the APOB gene, which is the first APOB mutation carrier identified in the Israeli population. Of the LDLR mutations, two were novel; p.(E140A) and a promoter variant, c.-191C>A. The c.2479G>A p.(V827I) in exon 17 of the LDLR gene was found in 8 patients (33.3% of the mutations) with modestly elevated LDL-C but also in a compound heterozygous patient with a clinical homozygous FH phenotype, consistent with this being a “mild” FH-causing variant. A significantly higher 6-SNP LDL-C score was found in mutation-negative cases compared with a normal Caucasian cohort (p=0.03), confirming that polygenic inheritance of common LDL-C raising SNPs can produce an FH phenocopy. Conclusions The results indicate a different spectrum of genetic causes of FH from that found previously, in concordance with the heterogeneous and changing origins of the Israeli population, and confirm that a polygenic cause is also contributing to the FH phenotype in Israel.

Background Among patients with acute coronary syndrome (ACS) who do not have diabetes, incident diabetes is common and associated with an adverse prognosis. Some data suggest that high density lipoprotein (HDL) has favourable effects on beta cell function and that cholesteryl ester transfer protein (CETP) inhibitors reduce incident type 2 diabetes in conjunction with increased HDL cholesterol (HDL-C) concentration. Dalcetrapib is a CETP inhibitor under ongoing evaluation as a potential cardiovascular therapy. Purpose We compared the effect of treatment with dalcetrapib or placebo on incident diabetes in patients with recent acute coronary syndrome (ACS). Methods In the dal-OUTCOMES trial, 15,871 patients were randomly assigned to treatment with dalcetrapib 600 mg or placebo daily, beginning 4–12 weeks after ACS. Absence of diabetes at baseline was based upon medical history, no use of diabetes medication, haemoglobin A1c Results At baseline, 10621 patients (67% of the trial cohort) did not have diabetes and formed the analysis cohort. Over median follow-up of 31 months, incident diabetes was identified in 392 of 5314 patients (7.4%) assigned to dalcetrapib and 505 of 5307 (9.5%) assigned to placebo (odds ratio [OR] 0.76; 95% confidence interval [CI] 0.66–0.87; P Conclusions In patients with recent ACS who do not have diabetes at baseline, incident diabetes is common. Dalcetrapib treatment reduced the relative risk of incident diabetes by 24% and the absolute risk by 2.1% over a median of 31 months. The reduction in incident diabetes with dalcetrapib was associated with increased HDL-C on treatment. Acknowledgement/Funding The dal-OUTCOMES trial was funded by F. Hoffmann LaRoche

We previously identified a highly consanguineous familial hypercholesterolemia (FH) family demonstrating segregation of the JD Bari mutation in the LDL receptor as well as a putative cholesterol-lowering trait. We aimed to identify genes related to the latter effect. LDL cholesterol (LDLc) values were normalized for FH affectation status, age, and gender. Using genome-wide SNP data, we examined whether known SNPs gleaned from a genome-wide association study could explain the variation observed in LDLc. Four individuals with markedly reduced LDL levels underwent whole exome sequencing. After prioritizing all potential mutations, we identified the most promising candidate genes and tested them for segregation with the lowering trait. We transfected a plasmid carrying the top candidate mutation, microsomal triglyceride transfer protein (MTTP) R634C, into COS-7 cells to test enzymatic activity. The SNP score explained 3% of the observed variability. MTTP R634C showed reduced activity (49.1 nmol/ml) compared with the WT allele (185.8 nmol/ml) (P = 0.0012) and was marginally associated with reduced LDLc in FH patients (P = 0.05). Phenotypic variability in a FH pedigree can only partially be explained by a combination of common SNPs and a rare mutation and a rare variant in the MTTP gene. LDLc variability in FH patients may have nongenetic causes.

STEMI is thought to occur as a result of a vulnerable coronary plaque rupture. Statins possess hypolipidemic and pleotropic effects that stabilize coronary plaque. We sought to determine the association between LDL-C levels, statin use prior to the index event on the type of acute coronary syndrome (ACS) presentation: STEMI vs. non-STEMI/unstable angina.Data was drawn from the ACS Israeli Survey (ACSIS), a biennial prospective survey of ACS patients hospitalized in all CCU/Cardiology departments during 2002-2010.Among 6790 patients, 2760 (41%) reported statin use prior to the index ACS event. The proportion of STEMI was significantly lower among statin treated vs. statin naive patients (36% vs. 57%, p0.0001). At each LDL-C level, the proportion of STEMI was significantly lower only among statin treated patients (p0.0001). LDL-C70 mg/dL was associated with a lower proportion of STEMI only among statin treated but not among statin naive patients (33% vs. 57%, p0.0001). Multivariate analysis revealed that statin use was independently associated with a lower probability of presenting with STEMI (ORadj=0.73, p=0.007), but not LDL-C70 mg/dL (ORadj=1.13, p=0.32). Patients on high-intensity statin therapy (HIST) were less likely to present with STEMI as compared with low-intensity statin therapy (LIST) or statin naive patients (27%, 38%, 56%, respectively, p for trend0.0001; HIST ORadj=0.28, p=0.01; LIST ORadj=0.48, p=0.026).Among patients admitted with ACS, statin use but not LDL-C level, was associated with a lower probability of presenting with STEMI. Patients on HIST had the lowest likelihood of presenting with STEMI.

Epidemiological data associate higher concentrations of high-density lipoprotein cholesterol (HDL-C) with lower cardiovascular risk. HDL-C isolated from healthy subjects exhibits potentially protective properties, including anti-inflammatory effects [(1)][1]. However, some evidence suggests that

Humanism in medicine is defined as health care providers' attitudes and actions that demonstrate respect for patients' values and concerns in relation to their social, psychological and spiritual life domains. Specifically, humanistic clinical medicine involves showing respect for the patient, building a personal connection, and eliciting and addressing a patient's emotional response to illness. Health information technology (IT) often interferes with humanistic clinical practice, potentially disabling these core aspects of the therapeutic patient-physician relationship. Health IT has evolved rapidly in recent years - and the imperative to maintain humanism in practice has never been greater. In this vision paper, we aim to discuss why preserving humanism is imperative in the design and implementation of health IT systems.

BACKGROUND Previous studies have established a correlation between coronary artery calcification (CAC) measured by ECG-gated chest computed tomography (CT) and cardiovascular disease. Recent reports which included asymptomatic patients suggest that CAC measured on non-ECG gated CT is similarly associated with cardiovascular risk. This study investigates the correlation between the Framingham Risk Score (FRS) and an incidental finding of CAC on a non-gated chest CT performed for non-cardiac indications in young and seemingly healthy adults. METHODS A cross-sectional study that included 162 CT scans performed in young patients aged 18-50 years old for non-cardiac indications in our institution was conducted. CAC score (CACS) was calculated using the Agatston method. FRS was calculated and compared to the CACS using three different approaches. The correlations between the CACS and several specific factors (i.e. age, body mass index, smoking, statins, etc.), were also evaluated. RESULTS Mean age of patients was 36.43 year old and 105 (64.8%) were male. We found a significant positive correlation between the CACS and the FRS in all three approaches (p

Little is known about whether cholesteryl ester transfer protein (CETP) genetic variation may modify the effect of weight-loss diets varying in fat content on changes in lipid levels. We analyzed the interaction between the CETP variant rs3764261 and dietary interventions on changes in lipid levels among 732 overweight/obese adults from a 2 year randomized weight-loss trial [Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST)], and replicated the findings in 171 overweight/obese adults from an independent 2 year weight-loss trial [Dietary Intervention Randomized Controlled Trial (DIRECT)]. In the POUNDS LOST, participants with the CETP rs3764261 CC genotype on the high-fat diet had larger increases in HDL cholesterol (P = 0.001) and decreases in triglycerides (P = 0.007) than those on the low-fat diet at 6 months, while no significant difference between these two diets was observed among participants carrying other genotypes. The gene-diet interactions on changes in HDL-cholesterol and tri­glyc­erides were replicated in the DIRECT (pooled P for interaction ≤ 0.01). Similar results on trajectory of changes in HDL cholesterol and triglycerides over the 2 year intervention were observed in both trials. Our study provides replicable evidence that individuals with the CETP rs3764261 CC genotype might derive greater effects on raising HDL cholesterol and lowering triglycerides by choosing a low-carbohydrate/high-fat weight-loss diet instead of a low-fat diet.

BACKGROUND Familial hypercholesterolemia (FH) is an autosomal-dominant disorder caused by mutations in 1 of 3 genes. In the 60% of patients who are mutation negative, we have recently shown that the clinical phenotype can be associated with an accumulation of common small-effect LDL cholesterol (LDL-C)-raising alleles by use of a 12–single nucleotide polymorphism (12-SNP) score. The aims of the study were to improve the selection of SNPs and replicate the results in additional samples. METHODS We used ROC curves to determine the optimum number of LDL-C SNPs. For replication analysis, we genotyped patients with a clinical diagnosis of FH from 6 countries for 6 LDL-C-associated alleles. We compared the weighted SNP score among patients with no confirmed mutation (FH/M–), those with a mutation (FH/M+), and controls from a UK population sample (WHII). RESULTS Increasing the number of SNPs to 33 did not improve the ability of the score to discriminate between FH/M– and controls, whereas sequential removal of SNPs with smaller effects/lower frequency showed that a weighted score of 6 SNPs performed as well as the 12-SNP score. Metaanalysis of the weighted 6-SNP score, on the basis of polymorphisms in CELSR2 (cadherin, EGF LAG 7-pass G-type receptor 2), APOB (apolipoprotein B), ABCG5/8 [ATP-binding cassette, sub-family G (WHITE), member 5/8], LDLR (low density lipoprotein receptor), and APOE (apolipoprotein E) loci, in the independent FH/M– cohorts showed a consistently higher score in comparison to the WHII population (P < 2.2 × 10−16). Modeling in individuals with a 6-SNP score in the top three-fourths of the score distribution indicated a >95% likelihood of a polygenic explanation of their increased LDL-C. CONCLUSIONS A 6-SNP LDL-C score consistently distinguishes FH/M– patients from healthy individuals. The hypercholesterolemia in 88% of mutation-negative patients is likely to have a polygenic basis.

Background Aldosterone may have adverse effects in the myocardium and vasculature. Treatment with an aldosterone antagonist reduces cardiovascular risk in patients with acute myocardial infarction complicated by heart failure (HF) and left ventricular systolic dysfunction. However, most patients with acute coronary syndrome do not have advanced HF. Among such patients, it is unknown whether aldosterone predicts cardiovascular risk. Methods and Results To address this question, we examined data from the dal‐OUTCOMES trial that compared the cholesteryl ester transfer protein inhibitor dalcetrapib with placebo, beginning 4 to 12 weeks after an index acute coronary syndrome. Patients with New York Heart Association class II (with LVEF III , or IV HF were excluded. Aldosterone was measured at randomization in 4073 patients. The primary outcome was a composite of coronary heart disease death, nonfatal myocardial infarction, stroke, hospitalization for unstable angina, or resuscitated cardiac arrest. Hospitalization for HF was a secondary endpoint. Over a median follow‐up of 37 months, the primary outcome occurred in 366 patients (9.0%), and hospitalization for HF occurred in 72 patients (1.8%). There was no association between aldosterone and either the time to first occurrence of a primary outcome (hazard ratio for doubling of aldosterone 0.92, 95% confidence interval 0.78‐1.09, P =0.34) or hospitalization for HF (hazard ratio 1.38, 95% CI 0.96‐1.99, P =0.08) in Cox regression models adjusted for covariates. Conclusions In patients with recent acute coronary syndrome but without advanced HF, aldosterone does not predict major cardiovascular events. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 00658515.

BACKGROUND: Familial hypercholesterolaemia (FH) is an autosomal dominant disease of lipid metabolism, which leads to early coronary heart disease. Mutations in LDLR, APOB and PCSK9 can be detected in 80% of definite FH (DFH) patients. This study aimed to identify novel FH-causing genetic variants in patients with no detectable mutation. METHODS AND RESULTS: Exomes of 125 unrelated DFH patients were sequenced, as part of the UK10K project. First, analysis of known FH genes identified 23 LDLR and two APOB mutations, and patients with explained causes of FH were excluded from further analysis. Second, common and rare variants in genes associated with low-density lipoprotein cholesterol (LDL-C) levels in genome-wide association study (GWAS) meta-analysis were examined. There was no clear rare variant association in LDL-C GWAS hits; however, there were 29 patients with a high LDL-C SNP score suggestive of polygenic hypercholesterolaemia. Finally, a gene-based burden test for an excess of rare (frequency

The two oxysterols, 27-hydroxycholesterol (27OH) and 24S-hydroxycholesterol (24OH), are both inhibitors of cholesterol synthesis and activators of the liver X receptor (LXR) in vitro. Their role as physiological regulators under in vivo conditions is controversial, however. In the present work, we utilized a previously described mouse model with overexpressed human sterol 27-hydroxylase (CYP27A1). The levels of 27OH were increased about 12-fold in the brain. The brain levels of HMG-CoA reductase mRNA and HMG-CoA synthase mRNA levels were increased. In accordance with increased cholesterol synthesis, most of the cholesterol precursors were also increased. The level of 24OH, the dominating oxysterol in the brain, was decreased by about 25%, most probably due to increased metabolism by CYP27A1. The LXR target genes were unaffected or slightly changed in a direction opposite to that expected for LXR activation. In the brain of Cyp27−/− mice, cholesterol synthesis was slightly increased, with increased levels of cholesterol precursors but normal mRNA levels of HMG-CoA reductase and HMG-CoA synthase. The mRNA levels corresponding to LXR target genes were not affected. The results are consistent with the possibility that both 24OH and 27OH are physiological suppressors of cholesterol synthesis in the brain. The results do not support the contention that 27OH is a general activator of LXR target genes in this organ.

Background & Aims Non-alcoholic steatohepatitis is characterized by hepatic steatosis with inflammation. Although steatosis is benign and reversible, inflammation can increase liver damage. Hepatic inflammation has been associated with accumulation of cholesterol in lysosomes of Kupffer cells. 27-Hydroxycholesterol (27HC), a derivative of cholesterol formed by CYP27A1, can mobilize cholesterol from the lysosomes to the cytoplasm. We investigated whether 27HC can change the intracellular distribution cholesterol and reduce hepatic inflammation in mice. Methods We transplanted bone marrow from irradiated wild-type or Cyp27a1 −/− mice to mice that do not express the low density lipoprotein receptor ( Ldlr −/− ), which are hyperlipidemic; 9 weeks later, mice were fed either regular chow or a high-fat, high-cholesterol (HFC) diet for 3 months. In a separate experiment, Ldlr −/− mice were given subcutaneous injections of 27HC and placed on regular chow or HFC diets for 3 weeks. Blood and liver tissues samples were collected and analyzed for intracellular cholesterol distribution and inflammation. Results In Ldlr −/− mice that received bone marrow transplants from Cyp27a1 −/− mice, lysosomes of Kupfer cells had a greater accumulation of cholesterol than those of mice that received bone marrow from wild-type mice, after the HFC diet. Liver histology and gene expression analyses showed increased inflammation and liver damage in mice given bone marrow transplants from Cyp27a1 −/− mice and placed on the HFC diet. Administration of 27HC to Ldlr −/− mice, following the HFC diet, reduced the accumulation of lysosomal cholesterol and hepatic inflammation, compared with mice that were not given 27HC. Conclusions Accumulation of cholesterol in lysosomes of Kupfer cells promotes hepatic inflammation in mice. The cholesterol derivative 27HC reduces accumulation of cholesterol in lysosomes and might be used to treat non-alcoholic steatohepatitis.

Glucose-control has a modest beneficial effect on cardiovascular outcomes in patients with type 2 diabetes mellitus. Thus, managing other atherogenic risk factors including hypertriglyceridemia, low HDL-cholesterol and moderately elevated LDL-cholesterol levels with increased small dense LDL-cholesterol fraction, is crucial. Insulin resistance is a key pathophysiologic factor in this population. Treatment starts with lifestyle modifications, but current best programmes have not translated into positive cardiovascular outcomes. Lowering LDL-cholesterol with statins is currently the main treatment strategy, but significant residual risk remains. Attempts to elevate HDL-cholesterol and to reduce triglycerides levels, with niacin or fibrates have not improved cardiovascular prognosis, but addition of ezetimibe, or fibrates in specific patients subgroups, have shown modest benefit. Some glucose-lowering medications and bariatric surgery may also improve diabetic dyslipidemia. Results of three major cardiovascular outcome trials evaluating the effect of lowering LDL-cholesterol with PCSK9 inhibitors in large cohorts that include thousands of diabetic patients are pending.

Drugs to raise HDL cholesterol (HDL-C) have generally failed to decrease major adverse cardiovascular events (MACE). HDL particle concentration (HDLP) has been proposed as a better predictor of MACE than HDL-C. We determined whether HDLP is associated with risk of MACE after acute coronary syndrome

Importance It is uncertain whether lipoprotein(a) [Lp(a)], which is associated with incident cardiovascular disease, is an independent risk factor for recurrent cardiovascular events after acute coronary syndrome (ACS). Objective To determine the association of Lp(a) concentration measured after ACS with the subsequent risk of ischemic cardiovascular events. Design, Setting, and Participants This nested case-cohort analysis was performed as an ad hoc analysis of the dal-Outcomes randomized clinical trial. This trial compared dalcetrapib, the cholesteryl ester transfer protein inhibitor, with placebo in patients with recent ACS and was performed between April 2008 and September 2012 at 935 sites in 27 countries. There were 969 case patients who experienced a primary cardiovascular outcome, and there were 3170 control patients who were event free at the time of a case event and had the same type of index ACS (unstable angina or myocardial infarction) as that of the respective case patients. Concentration of Lp(a) was measured by immunoturbidimetric assay. Data analysis for this present study was conducted from June 8, 2016, to April 21, 2017. Interventions Patients were randomly assigned to receive treatment with dalcetrapib, 600 mg daily, or matching placebo, beginning 4 to 12 weeks after ACS. Main Outcomes and Measures Death due to coronary heart disease, a major nonfatal coronary event (myocardial infarction, hospitalization for unstable angina, or resuscitated cardiac arrest), or fatal or nonfatal ischemic stroke. Results The mean (SD) age was 63 (10) years for the 969 case patients and 60 (9) years for the 3170 control patients, and both cohorts were composed of predominantly male (770 case patients [79%] and 2558 control patients [81%];P = .40) and white patients (858 case patients [89%] and 2825 control patients [89%];P = .62). At baseline, the median (interquartile range) Lp(a) level was 12.3 (4.7-50.9) mg/dL. There was broad application of evidence-based secondary prevention strategies after ACS, including use of statins in 4030 patients (97%). The cumulative distribution of baseline Lp(a) levels did not differ between cases and controls atP = .16. Case-cohort regression analysis showed no association of baseline Lp(a) level with risk of cardiovascular events. For a doubling of Lp(a) concentration, the hazard ratio (case to control) was 1.01 (95% CI, 0.96-1.06;P = .66) after adjustment for 16 baseline variables, including assigned study treatment. Conclusions and Relevance For patients with recent ACS who are treated with statins, Lp(a) concentration was not associated with adverse cardiovascular outcomes. These findings call into question whether treatment specifically targeted to reduce Lp(a) levels would thereby lower the risk for ischemic cardiovascular events after ACS. Trial Registration clinicaltrials.gov Identifier:NCT00658515

Macrophage scavenger receptor 1 (MSR1) mediates the uptake of modified low density lipoprotein (LDL)-cholesterol. The significance of MSR1 in atherosclerosis development in animal models is uncertain. In this study we sought to determine the significance of MSR1 polymorphisms in its encoding gene in susceptibility to atherosclerosis.We genotyped three polymorphic sites in the MSR1 gene including a 3-bp "TTA" insertion-deletion in intron 7 (rs3036811, Indel 7), an intron 5 SNP (rs33959637, IVS5-59), and a missense coding single nucleotide polymorphism (SNP) in exon 6 (rs3747531, P275A) in 136 nondiabetic Ashkenazi men under age 55 years (mean = 47.3 +/- 4.8 years) undergoing coronary angiography. Assessment of coronary disease was done by the number of segments with stenosis greater than 20% (coronary artery narrowing greater than 20% [CAGE20%]), greater than 50% (CAGE50%), and total number of diseased vessels. Linear regression modeling was used to define associations between atherosclerotic burden and MSR1 SNPs and haplotypes.Significant associations were noted between IVS5-59 and number of diseased vessels (p = 0.009) and CAGE20% (p = 0.017), which remained significant upon controlling for age, cholesterol level, hypertension, and smoking.This study demonstrates an association between MSR1 polymorphisms and atherosclerosis, suggesting that atherosclerotic risk associated with classic risk factors may be modified by MSR1 polymorphisms. These findings point to a significant role of MSR1 in atherosclerosis.

Hypertriglyceridemia (hyperTG) is a common form of dyslipidemia and is frequently associated with premature coronary disease, and when severe, recurrent events of pancreatitis may occur. The management of hyperTG is generally medical (life style modification, medications). Plasma exchange (PE) has been reported to be useful in emergency situations particularly when acute pancreatitis results from extreme hyperTG. To our knowledge, there is only one report on long-term use of PE for hyperTG. We here report our results of long-term treatment of hyperTG in 6 patients with Frederickson Type V hyperlipidemia who had recurrent attacks of pancreatitis due to hyperTG refractory to medical therapy. PE was performed from one to eight times a month, mostly using a Cobe Spectra apparatus. In total, our center has performed a total of 1,593 PE sessions for hyperTG. There were no safety issues associated with PE for hyperTG other than occasional access problems (clotted fistula, IV access problems). Determination of plasma TG levels before and after PE demonstrated high efficiency of TG removal (42% to 58% reduction). There was marked clinical improvement in recurrent pancreatitis; patients had a major decrease in episodes (39% to 100%) while on regular PE, as long as they adhered to the treatment schedule. We conclude that long-term PE for hyperTG, while costly, is feasible and safe and may reduce recurrent attacks of pancreatitis.

Background Cholesterol metabolism is mediated, in part, by the sterol-regulatory element binding proteins (SREBPs) that are activated by a SREBP cleavage-activating protein (SCAP). We examined whether coding variations in the interacting domains of both genes, are related to early-onset MI risk in a population-based case-control study from western Washington State. Methods Cases were 257 women, aged 18–59 years, and 320 men, aged 18–49 years, with first acute non-fatal MI; controls were 353 women and 311 men, similar in age, identified from the community who had no history of clinical CHD or stroke. Genotyping of the SREBF -2 G1784C polymorphism (SREBP-2-595A/G isoforms), and the SCAP A2386G polymorphism (SCAP-796I/V isoforms), were performed. Results After adjustment for age and race, the SREBP-2-595A isoform was associated with increased MI risk among men (OR=1.63, 95% CI=1.26–2.12). In contrast, there was little evidence for an association among women in a multiplicative model. However, compared to SREBP-2-595G homozygotes, homozygote women for the SREBP-2-595A isoform were at nearly two-fold increased risk (OR=1.95, 95% CI=1.07–3.54). Overall, SCAP genotypes were neither associated with MI in men nor in women. However, in men, SCAP genotypes were found to modify the association between SREBF- 2 and MI ( p -value for interaction=0.01). Conclusion The SREBP-2-595A isoform was associated with an increased risk of early-onset MI in U.S. men. The SCAP polymorphism appeared to modify the associations of SREBF -2 genotype with MI risk among men. These novel findings require confirmation in other populations.

27-Hydroxycholesterol (27OH) is a strong suppressor of cholesterol synthesis and a weak activator of LXR in vitro. The regulatory importance of 27OH in vivo is controversial. Here we utilized male mice with increased levels of 27OH either due to increased production (CYP27A1 transgenic mice) or reduced metabolism (Cyp7b1-/- mice). We also used mice lacking 27OH due to a knockout of Cyp27a1. The latter mice were treated with cholic acid to compensate for reduced bile acid synthesis. The effects of the different levels of 27OH on Srebp- and other LXR-regulated genes in the liver were investigated. In the liver of CYP27tg mice we found a modest increase of the mRNA levels corresponding to the LXR target genes Cyp7b1 and Abca1. A number of other LXR-regulated genes were not affected. The effect on Abca1 mRNA was not seen in the liver of Cyp7b1-/- mice. There were little or no effects on cholesterol synthesis. In the liver of the Cyp27-/- mice treated with 0.025% cholic acid there was no significant effect of the knockout on the LXR target genes. In a previous work triple-knockout mice deficient in the biosynthesis of 24S-hydroxycholesterol, 25-hydroxycholesterol and 27OH were shown to have impaired response to dietary cholesterol, suggesting side-chain oxidized oxysterols to be mediators in cholesterol-induced effects on LXR target genes at a transcriptional level (Chen W. et al., Cell Metab. 5 (2007) 73-79). The hydroxylated oxysterol responsible for the effect was not defined. We show here that treatment of wildtype mice with dietary cholesterol under the same conditions as in the above study induced the LXR target genes Lpl, Abcg8 and Srebp1c in wild type mice but failed to activate the same genes in mice lacking 27-hydroxycholesterol due to a knockout of Cyp27. We failed to demonstrate the above effects at the protein level (Abcg8) or at the activity level (Lpl). The results suggest that 27OH is not an important regulator of Srebp- or LXR regulated genes under basal conditions in mouse liver. On the other hand 27OH appears to mediate cholesterol-induced effects on some LXR target genes at a transcriptional level under some in vivo conditions.

BACKGROUND Recommendations for moderate alcohol consumption remain controversial, particularly in type 2 diabetes mellitus (T2DM). Long-term randomized, controlled trials (RCTs) are lacking. OBJECTIVE To assess cardiometabolic effects of initiating moderate alcohol intake in persons with T2DM and whether the type of wine matters. DESIGN 2-year RCT (CASCADE [CArdiovaSCulAr Diabetes & Ethanol] trial). (ClinicalTrials.gov: NCT00784433). SETTING Ben-Gurion University of the Negev-Soroka Medical Center and Nuclear Research Center Negev, Israel. PATIENTS Alcohol-abstaining adults with well-controlled T2DM. INTERVENTION Patients were randomly assigned to 150 mL of mineral water, white wine, or red wine with dinner for 2 years. Wines and mineral water were provided. All groups followed a Mediterranean diet without caloric restriction. MEASUREMENTS Primary outcomes were lipid and glycemic control profiles. Genetic measurements were done, and patients were followed for blood pressure, liver biomarkers, medication use, symptoms, and quality of life. RESULTS Of the 224 patients who were randomly assigned, 94% had follow-up data at 1 year and 87% at 2 years. In addition to the changes in the water group (Mediterranean diet only), red wine significantly increased high-density lipoprotein cholesterol (HDL-C) level by 0.05 mmol/L (2.0 mg/dL) (95% CI, 0.04 to 0.06 mmol/L [1.6 to 2.2 mg/dL]; P < 0.001) and apolipoprotein(a)1 level by 0.03 g/L (CI, 0.01 to 0.06 g/L; P = 0.05) and decreased the total cholesterol-HDL-C ratio by 0.27 (CI, -0.52 to -0.01; P = 0.039). Only slow ethanol metabolizers (alcohol dehydrogenase alleles [ADH1B*1] carriers) significantly benefited from the effect of both wines on glycemic control (fasting plasma glucose, homeostatic model assessment of insulin resistance, and hemoglobin A1c) compared with fast ethanol metabolizers (persons homozygous for ADH1B*2). Across the 3 groups, no material differences were identified in blood pressure, adiposity, liver function, drug therapy, symptoms, or quality of life, except that sleep quality improved in both wine groups compared with the water group (P = 0.040). Overall, compared with the changes in the water group, red wine further reduced the number of components of the metabolic syndrome by 0.34 (CI, -0.68 to -0.001; P = 0.049). LIMITATION Participants were not blinded to treatment allocation. CONCLUSION This long-term RCT suggests that initiating moderate wine intake, especially red wine, among well-controlled diabetics as part of a healthy diet is apparently safe and modestly decreases cardiometabolic risk. The genetic interactions suggest that ethanol plays an important role in glucose metabolism, and red wine's effects also involve nonalcoholic constituents. PRIMARY FUNDING SOURCE European Foundation for the Study of Diabetes.

Background and aims Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by mutations in the genes for LDL receptor ( LDLR ), apolipoprotein B ( APOB ) and proprotein convertase subtilisin/kexin type9 ( PCSK9). The purpose of the current investigation was to define the current spectrum of mutations causing FH in Israel. Methods New families were collected through the MEDPED (Make Early Diagnosis Prevent Early Death) FH program. Molecular analysis of the LDLR , PCSK9 and APOB genes was done using High Resolution Melt and direct sequencing in 67 index cases. A 6-SNP LDL-C gene score calculation for polygenic hypercholesterolaemia was done using TaqMan genotyping. Results Mean serum cholesterol was 7.48 ± 1.89 mmol/L and the mean serum LDL-C was 5.99 ± 1.89 mmol/L. Mutations in the LDLR and APOB gene were found in 24 cases (35.8%), with 16 in LDLR, none in PCSK9 and one, p.(R3527Q), in the APOB gene, which is the first APOB mutation carrier identified in the Israeli population. Of the LDLR mutations, two were novel; p.(E140A) and a promoter variant, c.-191C > A. The c.2479G > A p.(V827I) in exon 17 of the LDLR gene was found in 8 patients (33.3% of the mutations) with modestly elevated LDL-C, but also in a compound heterozygous patient with a clinical homozygous FH phenotype, consistent with this being a "mild" FH-causing variant. A significantly higher 6-SNP LDL-C score was found in mutation-negative cases compared with a normal Caucasian cohort ( p = 0.03), confirming that polygenic inheritance of common LDL-C raising SNPs can produce an FH phenocopy. Conclusions The results indicate a different spectrum of genetic causes of FH from that found previously, in concordance with the heterogeneous and changing origins of the Israeli population, and confirm that a polygenic cause is also contributing to the FH phenotype in Israel.

Importance We describe a deep intronic mutation in adult polyglucosan body disease. Similar mechanisms can also explain manifesting heterozygous cases in other inborn metabolic diseases. Objective To explain the genetic change consistently associated with manifesting heterozygous patients with adult polyglucosan body disease. Design, Setting, and Participants This retrospective study took place from November 8, 2012, to November 7, 2014. We studied 35 typical patients with adult polyglucosan body disease, of whom 16 were heterozygous for the well-known c.986A>C mutation in the glycogen branching enzyme gene (GBE1) but harbored no other known mutation in 16 exons. Main Outcomes and Measures All 16 manifesting heterozygous patients had lower glycogen branching activity compared with homozygous patients, which showed inactivation of the apparently normal allele. We studied the messenger ribonucleic acid (mRNA) structure and the genetic change due to the elusive second mutation. Results When we reverse transcribed and sequenced the mRNA ofGBE1, we found that all manifesting heterozygous patients had the c.986A>C mutant mRNA and complete lack of mRNA encoded by the second allele. We identified a deep intronic mutation in this allele,GBE1-IVS15 + 5289_5297delGTGTGGTGGinsTGTTTTTTACATGACAGGT, which acts as a gene trap, creating an ectopic last exon. The mRNA transcript from this allele missed the exon 16 and 3′UTR and encoded abnormal GBE causing further decrease of enzyme activity from 18% to 8%. Conclusions and Relevance We identified the deep intronic mutation, which acts as a gene trap. This second-most common adult polyglucosan body disease mutation explains another founder effect in all Ashkenazi-Jewish cases.

The prevalence of Crohn's disease depends on geographic location and racial background. Arg702Trp, Gly908Arg, and Leu1007fsinsC mutations in the NOD2/CARD15 gene are associated with Crohn's disease in Caucasians. The mutation rate among Israeli Jewish patients is 27%-41%. The prevalence of Crohn's disease is much lower in the Israeli Arab compared to the Israeli Jewish population. We studied the NOD2/CARD15 mutation rate and disease phenotype (according to the Vienna classification) among the Israeli Arabs and compared them with those in an Israeli Jewish cohort. We recruited 66 Israeli Arab patients and 122 ethnically matched controls. Five patients (8.2%) and three controls (2.3%) carried one NOD2/CARD15 mutation. The phenotypic characteristics of the Arab and Jewish patients were very similar. We conclude that NOD2/CARD15 mutations do not contribute to Crohn's susceptibility in the Israeli Arab population and suggest that NOD2/CARD15 mutations have an important effect on Crohn's prevalence within a specific population but not on the phenotype.

Background: Genetic variation in the alcohol dehydrogenase (ADH) enzyme is associated with an aversion to alcohol and a lower risk of alcoholism among Asians. There is growing evidence of a functional role of the ADH2*2 allele in alcohol-drinking patterns among Jews, who have traditionally exhibited low rates of alcoholism and alcohol-related problems. The mechanism by which this allelic effect is mediated is not yet clearly understood. This study examined the effect of ADH2*2 on alcohol-elimination rates (AER) under experimental conditions. Methods: Young adult male Jews (N= 109) received an intravenous alcohol infusion; metabolism was measured by using standard breath alcohol concentration tests. A clamping technique was used to achieve and maintain a target breath alcohol concentration of 50 mg/100 ml for a defined time period. The AER at steady state was calculated. The alcohol disappearance rate was also calculated from the descending limb slope. Polymerase chain reaction was used for allelic determination of the ADH2 and ADH3 loci. Results: The mean AER among ADH2*2 carriers was significantly higher (8.09 ± 1.4 g/hr) than among ADH2*1 homozygotes (7.14 ± 1.5 g/hr; p= 0.003). Significance was retained on adjustment for potential confounding covariates. The ADH2 allele explains 8.5% of the AER variance in this population. Little AER difference was observed across ADH3 genotype groups. The slope of the descending limb increased with increasing copies of the ADH2*2 allele. Conclusions: The rate of alcohol elimination is significantly associated with the ADH2 genotype of Jewish males. Evidence for variation in alcohol metabolism across ADH genotypic groups provides support for the role of physiologic protective factors in alcohol drinking and suggests that reduced drinking among Jews may be genetically as well as environmentally determined. We believe that application of the novel “Indiana clamp” enhances AER measurement accuracy, allowing for detection of hitherto undetectable differences.

The efficacy and safety of lipid-lowering agents in elderly individuals have not been extensively assessed. This population generally takes more drugs concurrently than middle-aged patients, and are therefore at higher risk of drug-drug interactions. This large-scale, randomized, double-blind, placebo-controlled study investigated the efficacy and safety of extended-release (XL) fluvastatin 80 mg once daily for up to 1 year in elderly patients with primary hypercholesterolemia. A total of 1229 patients (mean age, 75.5 years) were randomized. After 2 months of treatment, fluvastatin XL 80 mg significantly decreased plasma lipid levels from baseline compared with placebo; fluvastatin reduced total cholesterol by 25% compared with a decrease of 2.5% in the placebo group, low-density lipoprotein cholesterol was -33% vs. -2.5%, respectively, and triglycerides were -13.3% vs. 2.9%, respectively (p

Sterol 27-hydroxylase (CYP27A1) is required for bile acid synthesis by both the classical and alternate pathways. Cyp27a1 −/− mice exhibit a dramatic increase in the activity of cytochrome P450 3A (CYP3A), which catalyzes side-chain hydroxylations of bile acid intermediates, thereby facilitating their excretion in the bile and urine. We examine the role of the nuclear xenobiotic receptor PXR (pregnane X receptor) in this process. We demonstrate that expression of Cyp3a11 and other established PXR target genes is increased in the Cyp27a1 −/− mice. When Cyp27a1 −/− mice are fed a diet containing either cholic acid or chenodeoxycholic acid, expression of CYP7A1, which catalyzes the rate-limiting step in bile acid biosynthesis, is strongly suppressed. In parallel, the induction of Cyp3a11 observed in these mice is reversed, suggesting that bile acid intermediates serve as PXR activators. In support of this hypothesis, three potentially toxic sterols (7α-hydroxy-4-cholesten-3-one, 5β-cholestan-3α,7α,12α-triol, and 4-cholesten-3-one), including two that are known to accumulate in Cyp27a1 −/− mice, are efficacious activators of mouse PXR. All three compounds are more potent activators of mouse PXR than of human PXR, which may explain in part why humans who lack functional CYP27A1 do not display a corresponding increase in CYP3A activity and are stricken with the disease cerebrotendinous xanthomatosis. Taken together, these results reveal the existence of a feedforward regulatory loop by which potentially toxic bile acid intermediates activate PXR and induce their own metabolism. In addition, this study demonstrates that animal models with alterations in gene expression can be used to identify endogenous ligands for orphan nuclear receptors.

Sterol-regulatory element-binding protein (SREBP)-2 is a key regulator of cholesterol. When cells are deprived of cholesterol, proteolytic cleavage releases the NH 2 -terminal domain of SREBP-2 that binds and activates the promoters of SREBP-2-regulated genes including the genes encoding the low-density lipoprotein (LDL) receptor, 3-hydroxymethyl-3-glutaryl-(HMG-)CoA-synthase, and HMG-CoA-reductase. Thus, SREPB-2 gene activation leads to enhanced cholesterol uptake and biosynthesis. A novel protein polymorphism (SREBP-2-595A/G) discovered in the regulatory domain of human SREBP-2 was investigated regarding its impact on cholesterol homeostasis. In human embryonic kidney (HEK)-293-cells, the cleavage-rate of the SREBP-2-595A-isoform was slightly decreased compared to that of the SREBP-2-595G-isoform. Since cleavage of SREBP-2 activates the LDL receptor-mediated uptake of plasma cholesterol, we hypothesized the LDL receptor-mediated uptake to be decreased in homozygous SREBP-2-595A-carriers and thus, plasma total cholesterol (TC) to be higher than in SREBP-2-595G-carriers. Multiple linear regression analysis of population samples from Switzerland ( N =1334) and Israel ( N =923) demonstrated a significant positive, gene dose-dependent association of the SREBP-2-595A-isoform with higher plasma TC ( P =0.001). This cholesterol-modulating effect was present in hypercholesterolaemic (ΔTC=1.05 mmol/l, 14.4%; P =0.002; N =477), but absent in normocholesterolaemic subjects (ΔTC=0.06 mmol/l, 1.4%; P =0.334; N =1780). In summary, a slightly but constantly decreased cleavage-rate of the SREBP-2-595A-isoform compared to that of the SREBP-2-595G-isoform may lead to a reduced transcriptional activation of the LDL receptor-gene weakening the SREBP-mediated compensation mechanisms, and may, therefore, be a critical factor in the development of polygenic hypercholesterolaemia.

Background: In 1996, the first summary of molecular genetics of familial hypercholesterolemia (FH) in Israel was published (Reshef A, Hum Gen, 1996). Since then, new technology for mutation screening became available making genetic diagnosis easier more accurate, and more comprehensive. We performed systematic mutation screening of index cases of 68 pedigrees to reanalyze the profile of mutations among Israeli FH patients. Methods and results: In 68 individuals the entire coding region, promoter and intron-exon junctions of the LDLR and part of exon 26 of the APOB gene were screened for variants using High Resolution Melting, with Sanger sequencing of any identified melt shifts. Mutations of the LDLR gene were found in twenty-three patients (34% of the total) with seventeen different mutations . The most common mutation was p.(V827I) (47% of the detected mutations), not previously reported in Refech et al but reported to occur in patients from Russia. Three variants, two in exon 4 and one in the promoter region were not reported before; p.(C121S), p.(E140A) and c.-191 C>A. One patient carried the common APOB p.(R3527Q) mutation. 70% of the cohort were negative for an LDLR or APOB mutation. It was hypothesized that FH can be caused by an accumulation of LDL-C raising alleles each having a small contributive effect (Talmud et al., 2013). Using this published gene score method derived from twelve common LDL-C raising SNPs in eleven genes, the mean polygene score was significantly higher (p=0.03) among mutation negative Israeli FH patients compared with a European control population. Conclusion: We identified mutations in 30% of a new Israeli FH cohort. In these we found 3 novel LDLR mutations. The high prevalence of p.(V827I) likely reflects the change in demographics of the Israeli population since 1996 . In the remaining mutation free cohort, there is likely to be a polygenic cause of their elevated LDL-C and FH diagnosis. These data can help design a future strategy for early screening for FH in our population.