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• 88 children without FH were followed-up for 20 years. • Lp(a) and cIMT were measured at baseline and after 10- and 20 years. • At baseline, Lp(a) was elevated in 11.1% of the children. • Lp(a) did not contribute significantly to arterial wall thickening (measured by cIMT). Elevated lipoprotein(a) [Lp(a)] is independently associated with cardiovascular disease (CVD). In a recent long-term follow-up study involving children with familial hypercholesterolemia (FH), Lp(a) levels contributed significantly to early atherosclerosis, as measured by carotid intima-media thickness (cIMT). To determine if this holds true for children without FH, we conducted a 20-year follow-up study, examining 88 unaffected siblings (mean age: 12.9 years) of children with FH. No significant association was found between Lp(a) and cIMT during follow-up (ß-adjusted [95% confidence interval] = 0.0001 [-0.008 to 0.008] mm per 50 nmol/L increase Lp(a), p = 0.97). In conclusion, our findings suggest that elevated levels of Lp(a) do not play a significant role in arterial wall thickening among children without FH during the 20-year follow-up period. This leads us to consider the possibility that cIMT may not be a suitable marker for detecting potential subtle changes in the arterial wall mediated by Lp(a) in the young, general population. However, it could also be that elevated Lp(a) is only a significant risk factor for atherosclerosis in the presence of other risk factors such as FH. [ABSTRACT FROM AUTHOR]

Abstract Background and aims Heterozygous familial hypercholesterolemia (HeFH) is a common genetic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) and increased cardiovascular disease risk. Despite multiple LDL-C–lowering therapies, many HeFH patients do not reach LDL-C targets. Mipomersen, an antisense oligonucleotide against apolipoprotein B (apoB), might further lower LDL-C in HeFH patients. We assessed the efficacy and safety of two mipomersen dosing regimens in HeFH patients and explored whether thrice-weekly dosing improves the benefit-risk profile. Methods In this double-blind trial, HeFH patients (LDL-C >160 mg/dL) on maximal tolerated LDL-lowering therapy were randomized to mipomersen 200 mg once weekly (n = 104), mipomersen 70 mg thrice weekly (n = 102), or placebo in matching frequency (n = 103) for 60 weeks. Main outcomes were LDL-C, apoB, and lipoprotein(a) levels after 60 weeks of treatment. Results Mipomersen 200 mg once weekly and mipomersen 70 mg thrice weekly significantly lowered LDL-C compared with placebo by 21.0% and 18.8%, respectively, and apoB by 22.1% and 21.7% (all p < 0.001). Lipoprotein(a) was significantly lowered by 27.7% (p < 0.001) with thrice-weekly dosing. Injection-site reactions and flu-like symptoms led to discontinuation in 21.2% (200 mg), 17.6% (70 mg), and 5.8% (placebo) of participants. Alanine transaminase was elevated (≥3× upper limit of normal at least once) in 21.2%, 21.6%, and 1.0% of subjects, respectively. Conclusions Mipomersen 200 mg once weekly and 70 mg thrice weekly are effective in lowering apoB-containing lipoproteins in HeFH patients. This is counterbalanced by limited tolerability and increased hepatic transaminase levels in about 21% of patients. The thrice-weekly dosing regimen was associated with lower frequency of flu-like symptoms, which might help avert discontinuation in some patients, but otherwise had no major benefits. Graphical abstract Image 1 Highlights • Mipomersen 200 mg once weekly and 70 mg thrice weekly are effective in lowering apoB-containing lipoproteins in patients with heterozygous FH. • This effectiveness is counterbalanced by limited tolerability and increased hepatic transaminase levels in about 21% of patients. • Thrice-weekly dosing is associated with less flu-like symptoms and lower discontinuation rates, but otherwise had no major benefits. [ABSTRACT FROM AUTHOR]

Background Proprotein subtilisin kexin type 9 (PCSK9) and lipoprotein (a) [Lp(a)] levels are causative risk factors for coronary heart disease. Objectives The objective of the study was to determine the impact of lipid-lowering treatments on circulating PCSK9 and Lp(a). Methods We measured PCSK9 and Lp(a) levels in plasma samples from Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events trial patients with coronary heart disease and/or type II diabetes (T2D) mellitus. Patients received atorvastatin, which was titrated (10, 20, 40, or 80 mg/d) to achieve low-density lipoprotein cholesterol levels <100 mg/dL (baseline) and were subsequently randomized either to atorvastatin + torcetrapib, a cholesterol ester transfer protein inhibitor, or to atorvastatin + placebo. Results At baseline, both plasma PCSK9 and Lp(a) were dose-dependently increased with increasing atorvastatin doses. Compared with patients without T2D, those with T2D had higher PCSK9 (357 ± 123 vs 338 ± 115 ng/mL, P = .0012) and lower Lp(a) levels (28 ± 32 vs 32 ± 33 mg/dL, P = .0005). Plasma PCSK9 levels significantly increased in patients treated with torcetrapib (+13.1 ± 125.3 ng/mL [+3.7%], P = .005), but not in patients treated with placebo (+2.6 ± 127.9 ng/mL [+0.7%], P = .39). Plasma Lp(a) levels significantly decreased in patients treated with torcetrapib (−3.4 ± 10.7 mg/dL [−11.1%], P < .0001), but not in patients treated with placebo (+0.3 ± 9.4 mg/dL [+0.1%], P = .92). Conclusion In patients at high cardiovascular disease risk, PCSK9 and Lp(a) are positively and dose-dependently correlated with atorvastatin dosage, whereas the presence of T2D is associated with higher PCSK9 but lower Lp(a) levels. Cholesterol ester transfer protein inhibition with torcetrapib slightly increases PCSK9 levels and decreases Lp(a) levels. [ABSTRACT FROM AUTHOR]

Background Patients with autosomal dominant hypercholesterolemia (ADH), caused by mutations in either low-density lipoprotein receptor ( LDLR ), apolipoprotein B ( APOB ), or proprotein convertase subtilisin-kexin type 9 ( PCSK9 ) are characterized by high low-density lipoprotein cholesterol levels and in some studies also high lipoprotein(a) (Lp(a)) levels were observed. The question remains whether this effect on Lp(a) levels is gene-dose–dependent in individuals with either 0, 1, or 2 LDLR or APOB mutations. Objective We set out to study whether Lp(a) levels differ among bi-allelic ADH mutation carriers, and their relatives, in the Netherlands. Methods Bi-allelic ADH mutation carriers were identified in the database of the national referral laboratory for DNA diagnostics of inherited dyslipidemias. Family members were invited by the index cases to participate. Clinical parameters and Lp(a) levels were measured in bi-allelic ADH mutation carriers and their heterozygous and unaffected relatives. Results We included a total of 119 individuals; 34 bi-allelic ADH mutation carriers (20 homozygous/compound heterozygous LDLR mutation carriers (HoFH), 2 homozygous APOB mutation carriers (HoFDB), and 12 double heterozygotes for an LDLR and APOB mutation), 63 mono-allelic ADH mutation carriers (50 heterozygous LDLR [HeFH], 13 heterozygous APOB [HeFDB] mutation carriers), and 22 unaffected family members. Median Lp(a) levels in unaffected relatives, HeFH, and HoFH patients were 19.9 (11.1–41.5), 24.4 (5.9–70.6), and 47.3 (14.9–111.7) mg/dL, respectively ( P = .150 for gene-dose dependency). Median Lp(a) levels in HeFDB and HoFDB patients were 50.3 (18.7–120.9) and 205.5 (no interquartile range calculated), respectively ( P = .012 for gene-dose-dependency). Double heterozygous carriers of LDLR and APOB mutations had median Lp(a) levels of 27.0 (23.5–45.0), which did not significantly differ from HoFH and HoFDB patients ( P = .730 and .340, respectively). Conclusion A (trend toward) increased plasma Lp(a) levels in homozygous ADH patients compared with both heterozygous ADH and unaffected relatives was observed. Whether increased Lp(a) levels in homozygous ADH patients add to the increased cardiovascular disease risk and whether this risk can be reduced by therapies that lower both low-density lipoprotein cholesterol and Lp(a) levels remains to be elucidated. [ABSTRACT FROM AUTHOR]

Aims Low HDL-C is a potent risk factor for cardiovascular disease (CVD). Yet, mutations in ABCA1, a major determinant of circulating HDL-C levels, were previously not associated with CVD risk in cohort studies. To study the consequences of low plasma levels of high-density lipoprotein cholesterol (HDL-C) due to ATP-binding cassette transporter A1 (ABCA1) dysfunction for atherosclerotic vascular disease in the carotid arteries. Methods and results We performed 3.0 Tesla magnetic resonance imaging (MRI) measurements of the carotid arteries in 36 carriers of high impact functional ABCA1 mutations and 36 normolipidemic controls. Carriers presented with 42% lower HDL-C levels (P < 0.001), a larger mean wall area (18.6 ± 6.0 vs. 15.8 ± 4.3 mm2; P = 0.02), a larger mean wall thickness (0.82 ± 0.21 vs. 0.70 ± 0.14 mm; P = 0.005), and a higher normalized wall index (0.37 ± 0.06 vs. 0.33 ± 0.04; P = 0.005) compared with controls, retaining significance after adjustment for smoking, alcohol consumption, systolic blood pressure, diabetes, body mass index, history of CVD, LDL-C, and statin use (P = 0.002). Conclusion Carriers of loss of function ABCA1 mutations display a larger atherosclerotic burden compared with age and sex-matched controls, implying a higher risk for CVD. Further studies are needed to elucidate the full function of ABCA1 in the protection against atherosclerosis. These data support the development of strategies to up-regulate ABCA1 in patients with established CVD. [ABSTRACT FROM PUBLISHER]

Aims A randomized, double-blind, placebo-controlled study was conducted to investigate the safety and efficacy of mipomersen, an apolipoprotein B-100 (apoB) synthesis inhibitor, in patients who are statin intolerant and at high risk for cardiovascular disease (CVD). Methods and results Thirty-three subjects, not receiving statin therapy because of statin intolerance, received a weekly subcutaneous dose of 200 mg mipomersen or placebo (2:1 randomization) for 26 weeks. The primary endpoint was per cent change in LDL cholesterol (LDL-c) from the baseline to Week 28. The other efficacy endpoints were per cent change in apoB and lipoprotein a [Lp(a)]. Safety was determined using the incidence of treatment-emergent adverse events (AEs) and clinical laboratory evaluations. After 26 weeks of mipomersen administration, LDL-c was reduced by 47 ± 18% (P < 0.001 vs. placebo). apoB and Lp(a) were also significantly reduced by 46 and 27%, respectively (P < 0.001 vs. placebo). Four mipomersen (19%) and two placebo subjects (17%) discontinued dosing prematurely due to AEs. Persistent liver transaminase increases ≥3× the upper limit of normal were observed in seven (33%) subjects assigned to mipomersen. In selected subjects, liver fat content was assessed, during and after treatment, using magnetic resonance spectroscopy. Liver fat content in these patients ranged from 0.8 to 47.3%. Liver needle biopsy was performed in two of these subjects, confirming hepatic steatosis with minimal inflammation or fibrosis. Conclusion The present data suggest that mipomersen is a potential therapeutic option in statin-intolerant patients at high risk for CVD. The long-term follow-up of liver safety is required. [ABSTRACT FROM PUBLISHER]

Aims Mipomersen, an apolipoprotein (apo) B synthesis inhibitor, has been shown to produce potent reductions in apoB and LDL-cholesterol levels in animal models as well as healthy human volunteers. A randomized, double-blind, placebo-controlled, dose-escalation study was designed to evaluate the efficacy and safety of mipomersen monotherapy with or without dose loading in subjects with mild-to-moderate hyperlipidaemia. Methods and results Fifty subjects with LDL-cholesterol levels between 119 and 266 mg/dL were enrolled into five cohorts at a 4:1 randomization ratio of active to placebo. Two 13-week dose regimens were evaluated at doses ranging from 50 to 400 mg/week. Mipomersen produced dose-dependent reductions in all apoB containing lipoproteins. In the 200 and 300 mg/week dose cohorts, mean reductions from baseline in LDL cholesterol were −45 ± 10% (P= 0.000) and −61 ± 8% (P= 0.000), corresponding to a −46 ± 11% (P= 0.000) and −61 ± 7% (P= 0.000) decrease in apoB levels. Triglyceride levels were also lowered with median reductions up to 53% (P= 0.021). The most common adverse events were injection site reactions. Seven of 40 subjects (18%) showed consecutive trans-aminase elevations >3× upper limit of normal. Five of these subjects received 400 mg/week, four of whom had apoB levels below the limit of detection. As a consequence, the 400 mg/week cohort was discontinued. Conclusions Mipomersen administered as monotherapy in subjects with mild-to-moderate hyperlipidaemia produced potent reductions in all apoB-containing lipoproteins. Higher doses were associated with hepatic trans-aminase increases. [ABSTRACT FROM PUBLISHER]

Background: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an independent risk factor of cardiovascular disease and a target of treatment. Lp-PLA2 levels in children have not been previously reported. The effect of statin therapy on Lp-PLA2 mass and activity in children with familial hypercholesterolemia (FH) is also not known. Methods: Lp-PLA2 mass and activity levels were measured at baseline and after 2 years in 178 children with FH randomized to pravastatin or placebo and in 78 unaffected and untreated siblings. At the end of the randomized period, all FH children were then placed on pravastatin for an additional 2 years, and Lp-PLA2 mass and activity levels were correlated with changes in carotid intima-media thickness during 4 years of follow-up. Results: Baseline levels of Lp-PLA2 mass and activity were significantly greater in children with FH compared with unaffected siblings (mass: 240.3 ± 41.6 vs 222.1 ± 36.5 ng/mL, P = .002; activity: 205.7 ± 41.6 vs 124.3±23.0 nmol/min/mL, P < .0001). In the randomized FH cohort, after 2 years treatment, Lp-PLA2 mass (217.8 ± 35.0 vs 231.5 ± 34.8 ng/mL, P = .001) and activity (178.8 ± 37.3 vs 206.2 ± 33.5 nmol/min/mL, P < .0001) were significantly reduced by pravastatin compared with placebo. Change in Lp-PLA2 activity was related to change in low-density lipoprotein cholesterol (pravastatin: r = 0.53, P < .0001, placebo: r = 0.23, P < .001) but change in Lp-PLA2 mass was not related to change in low-density lipoprotein cholesterol. Baseline levels of Lp-PLA2 mass and activity were not significantly associated with carotid intima-media thickness at baseline or at 4 years. Conclusion: Lp-PLA2 mass and activity are significantly elevated in children with heterozygous FH compared with unaffected siblings and are significantly reduced by pravastatin therapy. [Copyright &y& Elsevier]

Background Plasma apolipoprotein C-III (apoC-III) levels are associated with coronary artery disease (CAD) risk. Objective To assess whether lipoprotein-associated apoC-III levels predict risk of CAD events. Methods apoC-III associated with apoB, apoAI, and Lp(a) (apoCIII-apoB, apoCIII-apoAI, and apoCIII-Lp(a), respectively) were measured using high-throughput chemiluminescent enzyme-linked immunoassays in 2711 subjects (1879 controls and 832 cases with CAD) in the European Prospective Investigation into Cancer and Nutrition-Norfolk prospective population study with 7.4 years of follow-up. These measures were correlated with a variety of lipid measurements and the presence of CAD. The indices of "total apoCIII-apoB" and "total apoCIII-apoAI" were derived by multiplying plasma apoB and apoAI, respectively. Results apoCIII-apoB (P =.001), apoCIII-Lp(a) (P <.001), apoCIII-apoAI (P =.005) were higher in cases vs controls; tended to correlate positively with body mass index, hsCRP, apoC-III, low-density lipoprotein (LDL) cholesterol, triglycerides, remnant cholesterol, very low density lipoprotein, LDL and high-density lipoprotein particle number and very low density lipoprotein size; but negatively with LDL and high-density lipoprotein particle size (P <.001 for all). apoCIII-apoB, apoCIII-apoAI, apoCIII-Lp(a), total apoCIII-Lp(a), and total apoCIII-apoB were predictors of CAD after adjustment of age, sex, body mass index, smoking, diabetes, hypertensive and lipid-lowering drug use, but they lost their significance after further adjustment of lipid and lipoprotein variables. Conclusions This study suggests that enzyme-linked immunoassay–measured lipoprotein-associated apoC-III markers reflect atherogenic lipid particles but do not independently predict risk of CAD events. Highlights • High-throughput enzyme-linked immunoassays were developed to measure lipoprotein-associated apolipoprotein C-III (apoC-III) levels. • apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoAI were measured in EPIC-Norfolk. • apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoAI reflect atherogenic lipid particles. • apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoAI do not independently predict risk of coronary artery disease events. • Their role in patients with prior history of coronary artery disease needs to be evaluated. [ABSTRACT FROM AUTHOR]

Background TA-8995 is a potent inhibitor of cholesteryl ester transfer protein (CETP) with beneficial effects on lipids and lipoproteins. The effect of TA-8995 on cholesterol efflux capacity (CEC), a measure of high-density lipoprotein (HDL) function, and HDL subparticle distribution is largely unknown. Objective To assess the effect of the CETP inhibitor TA-8995 on ABCA1- and non–ABCA1-driven CEC and on HDL particle distribution. Methods Total, non–ABCA1-, and ABCA1-specific CEC from J774 cells and HDL subclass distribution assessed by two-dimensional gel electrophoresis were measured at baseline and after 12-week treatment in 187 mild-dyslipidemic patients randomized to placebo, 1 mg, 5 mg, 10 mg TA-8995, or 10 mg TA-8995 combined with 10 mg rosuvastatin (NCT01970215). Results Compared with placebo, total, non–ABCA1-, and ABCA1-specific CEC were increased dose dependently by up to 38%, 72%, and 28%, respectively, in patients randomized to 10 mg of TA-8995. PreBeta-1 HDL, the primary acceptor for ABCA1-driven cholesterol efflux, was increased by 36%. This increase in preBeta-1 HDL correlated significantly with the total and the ABCA1-driven CEC increase, whereas the high-density lipoprotein cholesterol (HDL-C) increase did not. Conclusion TA-8995 dose dependently increased not only total and non–ABCA1-specific CEC but also ABCA1-specific CEC and preBeta-1 HDL particle levels. These findings suggest that TA-8995 not only increases HDL-C levels but also promotes functional properties of HDL particles. This CETP inhibitor–driven preBeta-1 HDL increase is an important predictor of both ABCA1 and total CEC increase, independent of HDL-C increase. Whether these changes in HDL particle composition and functionality have a beneficial effect on cardiovascular outcome requires formal testing in a cardiovascular outcome trial. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Secretory phospholipase A2 (sPLA2) enzymes are thought to contribute to atherosclerosis. In this study we assessed levels of sPLA2 mass and activity, and their relationship to baseline characteristics of children with familial hypercholesterolemia (FH). Furthermore, we evaluated the effect of two years of pravastatin therapy on sPLA2 levels. Methods and results: sPLA2-IIA mass and sPLA2 activity were measured at baseline and after two years in 187 children with FH (aged 8–18 years) randomized to pravastatin or placebo. At baseline, median [IQR] sPLA2-IIA mass and sPLA2 activity levels were 7.2 [5.8–13.2] ng/ml and 36.4 [29.8–47.1] U/ml, respectively. Both sPLA2-IIA mass and sPLA2 activity were significantly correlated with high-sensitivity C-reactive protein (r = 0.33, p < 0.001 and r = 0.386, p < 0 .001, respectively), but not with other cardiovascular risk factors. Baseline levels of sPLA2-IIA mass and sPLA2 activity were not significantly associated with carotid intima-media thickness (cIMT) at baseline or at the end of follow-up. After two years, sPLA2-IIA mass and sPLA2 activity levels were not significantly reduced in the pravastatin group (p = 0.20 and p = 0.63, respectively), nor in the placebo group (p = 0.17 and p = 0.11, respectively). Changes from baseline did not differ between the treatment groups for sPLA2-IIA mass (p = 0.48) and sPLA2 activity (p = 0.88). Conclusions: sPLA2-IIA mass and sPLA2 activity were not significantly associated with cIMT in our pediatric FH cohort. This could indicate that the potential predictive role of sPLA2 as a biomarker of cardiovascular disease in children with FH is limited. Treatment with pravastatin did not reduce sPLA2-IIA mass or sPLA2 activity levels, as compared to placebo. Further studies with larger samples are required to address these issues. [Copyright &y& Elsevier]

Objectives: The goal of this study was to determine whether residual risk after high-dose statin therapy for primary prevention individuals with reduced levels of low-density lipoprotein cholesterol (LDL-C) is related to on-treatment apolipoprotein B, non–high-density lipoprotein cholesterol (non–HDL-C), trigylcerides, or lipid ratios, and how they compare with on-treatment LDL-C. Background: Guidelines focus on LDL-C as the primary target of therapy, yet residual risk for cardiovascular disease (CVD) among statin-treated individuals remains high and not fully explained. Methods: Participants in the randomized placebo-controlled JUPITER (Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin) trial were adults without diabetes or CVD, with baseline LDL-C levels <130 mg/dl, high-sensitivity C-reactive protein levels ≥2 mg/l, and triglyceride concentrations <500 mg/dl. Individuals allocated to receive rosuvastatin 20 mg daily with baseline and on-treatment lipids and lipoproteins were examined in relation to the primary endpoint of incident CVD (nonfatal myocardial infarction or stroke, hospitalization for unstable angina, arterial revascularization, or cardiovascular death). Results: Using separate multivariate Cox models, statistically significant associations of a similar magnitude with residual risk of CVD were found for on-treatment LDL-C, non–HDL-C, apolipoprotein B, total cholesterol/HDL-C, LDL-C/HDL-C, and apolipoprotein B/A-I. The respective adjusted standardized hazard ratios (95% confidence intervals) for each of these measures were 1.31 (1.09 to 1.56), 1.25 (1.04 to 1.50), 1.27 (1.06 to 1.53), 1.22 (1.03 to 1.44), 1.29 (1.09 to 1.52), and 1.27 (1.09 to 1.49). The overall residual risk and the risk associated with these measures decreased among participants achieving on-treatment LDL-C ≤70 mg/dl, on-treatment non–HDL-C ≤100 mg/dl, or on-treatment apolipoprotein B ≤80 mg/dl. In contrast, on-treatment triglycerides showed no association with CVD. Conclusions: In this primary prevention trial of nondiabetic individuals with low LDL-C and elevated high-sensitivity C-reactive protein, on-treatment LDL-C was as valuable as non–HDL-C, apolipoprotein B, or ratios in predicting residual risk. (JUPITER—Crestor 20mg Versus Placebo in Prevention of Cardiovascular [CV] Events; NCT00239681) [Copyright &y& Elsevier]

Objectives: The aim of this study was to investigate the role of reduced lecithin: cholesterol acyltransferase (LCAT) function on atherogenesis using 3.0-T carotid magnetic resonance imaging (MRI) and B-mode ultrasound. Background: The role of low high-density lipoprotein cholesterol as a causal factor in atherogenesis has recently been questioned. LCAT plays a key role in high-density lipoprotein cholesterol metabolism. Methods: Carotid 3.0-T MRI and B-mode ultrasound measurements were performed in 40 carriers of LCAT gene mutations and 40 controls, matched for age. Patients with cardiovascular disease were excluded. Results: Carriers had 31% lower LCAT activity levels and 38% decreased high-density lipoprotein cholesterol levels (both p < 0.001 vs. controls). Carriers presented with a 10% higher normalized wall index (0.34 ± 0.07 vs. 0.31 ± 0.04, p = 0.002), a 22% higher mean wall area (17.3 ± 8.5 mm2 vs. 14.2 ± 4.1 mm2, p = 0.01), and a 22% higher total wall volume (1,039 ± 508 mm3 vs. 851 ± 247 mm3, p = 0.01 vs. controls) as measured by MRI. The prevalence (20 vs. 5, p = 0.002) and the total volume (102 mm3 vs. 3 mm3) of atherosclerotic plaque components on MRI relating to lipid-rich tissue or calcification were also higher in carriers than in controls. All differences retained significance after adjustment for age, sex, blood pressure, low-density lipoprotein cholesterol, body mass index, smoking, and family history of cardiovascular disease. Common carotid intima-media thickness measured with ultrasound was increased in carriers by 12.5% (0.72 ± 0.33 mm vs. 0.64 ± 0.15 mm, p = 0.14). Conclusions: Carriers of LCAT gene mutations exhibit increased carotid atherosclerosis, indicating an increased risk of cardiovascular disease. The present findings imply that increasing LCAT activity may be an attractive target in cardiovascular prevention strategies. [Copyright &y& Elsevier]

Abstract: Objectives: We prospectively investigated the effects of ATP-binding cassette protein-1 (ABCA1) variants on long-term clinical outcome in patients with coronary artery disease (CAD). Background: ABCA1 is implicated in the etiology of atherothrombosis and may offer a target to reduce cardiovascular risk. However, the impact of ABCA1 on recurrent cardiovascular disease in a secondary prevention setting is as of yet unknown. Methods: We studied cause-specific 10-year mortality and quantitative coronary angiography data from the Regression GRowth Evaluation Statin Study (REGRESS), comprising 884 male CAD patients genotyped for promoter variants encompassing a proximal regulatory region (rs2422493, rs1800976, rs2740483 and rs1800977). Kaplan–Meier, proportional hazards and haplotype analyses were used to ascertain single-variant and multi-marker effects on absolute risk and extent of CAD. Results: Protection from 10-year vascular death could be attributed to the rs2422493 genotype (available in 639 patients) T allele with absolute risk decreasing stepwise from 12.2% to 8.6% to 4.7% per each added allele copy, HR 0.64, p =0.03 and HR 0.53, p =0.04 in the TGCC haplotype context. The TGCC (p =0.04) and TCCT (p =0.003) haplotypes exhibited less extensive CAD. Conclusions: On a background of contemporary secondary prevention, variation in the ABCA1 promoter influences 10-year risk of vascular death and angiographic extent of CAD in men. These insights contribute to identification of patients sharing a specific prognosis, understanding of its etiological basis and development of strategies of risk reduction in CAD. [Copyright &y& Elsevier]

Objectives: This study sought to assess whether oxidation-specific biomarkers are associated with an increased risk of coronary artery disease (CAD) events. Background: The relationship of a panel of oxidative biomarkers and lipoprotein(a) [Lp(a)] to CAD risk is not fully determined. Methods: A prospective case-control study nested in the EPIC (European Prospective Investigation of Cancer)-Norfolk cohort of 45- to 79-year-old apparently healthy men and women followed for ∼6 years was designed. Cases consisted of participants in whom fatal or nonfatal CAD developed, matched by sex, age, and enrollment time with controls without CAD. Baseline levels of oxidized phospholipids on apolipoprotein B-100 particles and Lp(a) were measured in 763 cases and 1,397 controls. Their relationship to secretory phospholipase A2 type IIA mass and activity, myeloperoxidase mass, and lipoprotein-associated phospholipase A2 activity and association with CAD events were determined. Results: After adjusting for age, smoking, diabetes, low- and high-density lipoprotein cholesterol, and systolic blood pressure, the highest tertiles of oxidized phospholipids on apolipoprotein B-100 particles and Lp(a) were associated with a significantly higher risk of CAD events (odds ratios: 1.67 and 1.64, respectively; p < 0.001) compared with the lowest tertiles. The odds ratio of CAD events associated with the highest tertiles of oxidized phospholipids on apolipoprotein B-100 particles or Lp(a) was significantly potentiated (approximately doubled) by the highest tertiles of secretory phospholipase A2 activity and mass but less so for myeloperoxidase and lipoprotein-associated phospholipase A2 activity. The odds ratios for fatal CAD were higher than for the combined end point. After taking into account the Framingham Risk Score, c-index values progressively increased when oxidative biomarkers were added to the model. Conclusions: This EPIC-Norfolk study links pathophysiologically related oxidation-specific biomarkers and Lp(a) with CAD events. Oxidation-specific biomarkers provide cumulative predictive value when added to traditional cardiovascular risk factors. [Copyright &y& Elsevier]

Abstract: Peripheral lipoprotein lipase (LPL)-mediated lipolysis of triglycerides is the first step in chylomicron/VLDL clearance involving heparan sulfate proteoglycans (HSPGs) displayed at the cell surface of the capillaries in adipose tissue, heart and skeletal muscle. The newly generated chylomicron remnant particles are then cleared by the liver, whereas VLDL remnant particles are either further modified, through the action of hepatic lipase (HL) and cholesteryl ester transfer protein (CETP), into LDL particles or alternatively directly cleared by the liver. Two proteins, lipase maturation factor 1 (LMF1) and glycosylphosphatidylinositol-anchored high density lipoprotein binding protein 1 (GPIHBP1), have been recently identified and have revised our current understanding of LPL maturation and LPL-mediated lipolysis. Moreover, new insights have been gained with respect to hepatic remnant clearance using genetically modified mice targeting the sulfation of HSPGs and even deletion of the most abundant heparan sulfate proteoglycan: syndecan1. In this review, we will provide an overview of novel data on both peripheral TG hydrolysis and hepatic remnant clearance that will improve our knowledge of plasma triglyceride metabolism. [Copyright &y& Elsevier]

Abstract: Background: Very few, if any, studies have assessed the ability of apolipoproteins to predict new-onset of congestive heart failure (HF) in statin-treated patients with coronary heart disease (CHD). Aims: To employ the Incremental Decrease in End points Through Aggressive Lipid Lowering Trial (IDEAL) study database to assess the association of on-treatment lipoprotein components with prediction of HF events and to compare their predictive value with that of established risk factors such as hypertension and diabetes. Methods: We used Cox regression models to study the relationships between on-treatment levels of apolipoproteins A1 and B to subsequent HF. Chi square information value from the log likelihood was used to compare the predictive value of lipoprotein components with established risk factors of HF. Findings: In the IDEAL study, on-treatment apolipoproteins proved to be associated with the occurrence of new-onset HF. Variables related to low-density lipoprotein cholesterol (LDL-C) carried less predictive information than those related to high-density lipoprotein cholesterol (HDL-C), and apoA-1 was the single variable most strongly associated with HF. LDL-C was less predictive than both non-HDL-C (total cholesterol minus HDL-C) and apoB. The ratio of apoB to apoA-1 was most strongly related to HF after adjustment for potential confounders, among which diabetes had a stronger correlation with HF than did hypertension. ApoB/apoA-1 carried approximately 2.2 times more of the statistical information value than that of diabetes. Calculation of the net reclassification improvement index revealed that about 3.7% of the patients had to be reclassified into more correct categories of risk once apoB/apoA-1 was added to the adjustment factors. The reduction in risk by intensive lipid-lowering treatment as compared to usual-dose simvastatin was well predicted by the difference in apoB/apoA-1 on-treatment levels. Interpretation: The on-treatment ratio of apoB/apoA-1 was the strongest predictor of HF in CHD patients of both IDEAL treatment arms combined, mostly driven by the strong association with apoA-1, whereas LDL-C and non-HDL-C were less able to predict HF outcome. The predictive information value contained within apoB/apoA-1 was about 2.2 times more than that of diabetes. Between-treatment group differences in HF were to a significant extent explained by on-treatment differences in apoB/apoA-1, mostly through the changes in apoB. We argue therefore, on-treatment lipoprotein components contribute to the overall future risk of HF in statin-treated patients with CHD. [Copyright &y& Elsevier]

Abstract: Rationale: Lipoprotein lipase (LPL) X447 homozygotes are characterized by enhanced conversion of TRL apoB100. Here, we set out to investigate whether this LPL variant is also associated with enhanced apoB48 clearance. Therefore, we evaluated apoB48 kinetics in X447 homozygotes in the fed state by infusion of isotope l-[1-13C]-valine and subsequent compartmental modeling. Methods and results: ApoB48 metabolism was assessed in five X447 homozygotes (X/X genotype) and five S447 homozygotes (S/S genotype). Subjects were continuously fed and received infusion of stable isotope l-[1-13C]-valine. Results were analyzed by SAAM II modeling. Fasting (2.4-fold, p =0.02) as well as non-fasting (1.6-fold, p =0.09) apoB48 concentration was increased in the X447 homozygotes compared to S447 homozygotes. In addition, the X447 homozygotes exhibited a 1.7-fold higher apoB48 poolsize (p =0.04). Interestingly, apoB48 fractional catabolic rate (FCR) was 1.9-fold higher (p =0.007) and apoB48 synthesis was more than two-fold higher (p =0.006) in the X447 homozygotes compared to S447 homozygotes. Conclusion: In the present study, we show that X447 homozygotes exhibit enhanced apoB48 clearance. Previously, these homozygotes were shown to present with enhanced apoB100 TRL conversion. Combined, this LPLS447X gain of function variant affects apoB48 as well as apoB100 TRL metabolism. [Copyright &y& Elsevier]

Abstract: Background: Overexpression of lipoprotein lipase (LPL) protects against atherosclerosis in genetically engineered mice. We tested whether a gene therapy vector that delivers human (h) LPLS447X cDNA to skeletal muscle could induce similar effects. Methods: LDL receptor knockout (LDLr−/−) mice were injected intramuscular (IM) with adeno-associated virus serotype 1 (AAV1) LPLS447X or PBS. Four weeks later they were started on an atherogenic diet for 12 weeks. After termination, atherosclerosis was assessed and homogenates of muscle and liver tissue were analyzed. Results: AAV1-treated mice showed hLPL concentrations of 768±293ng/mL in post-heparin plasma associated with 48% reductions of fasting triglycerides (TG) levels (p <0.0001). In the absence of an effect on total cholesterol (TC) levels, no effects on atherosclerosis were found. An increase in lipid content of injected muscles was accompanied by a significant decrease of TG (−20%, p <0.0001) and free cholesterol (FC) content (−24%, p <0.0001) in liver homogenates. Conclusions: The data show that transgenic hLPLS447X on top of endogenous murine LPL reduces fasting TG levels in plasma but has no effect on atherosclerosis in LDLr−/− mice. While lipid accumulation in the injected muscle was anticipated, this coincided with an interesting decrease of both TG and FC in liver homogenates. [Copyright &y& Elsevier]

Abstract: Studies on the clinical consequences of different low-density lipoprotein (LDL) receptor genotypes in adult patients have yielded conflicting results. We hypothesized that children with familial hypercholesterolemia (FH) provide a better model to perform genotype–phenotype analyses than adults. We tested this hypothesis and assessed the effect of LDL receptor genotypes on lipoprotein levels and on parental risk of cardiovascular disease (CVD) in a pediatric FH cohort. We identified 75 different LDL receptor mutations in 645 children with heterozygous FH; in these children, null alleles were clearly associated with more elevated LDL cholesterol levels compared to receptor-defective mutations. Familial factors explained 50.4% of the variation in LDL cholesterol levels of this pediatric cohort compared to only 9.5% in adults. Parental CVD risk was not significantly different between carriers of null alleles and receptor-defective mutations (RR, 1.22; 95% CI, 0.76–1.95; p =0.4). The N543H/2393del9 mutation was associated with a less deteriorated lipid profile and the parents had less often CVD relative to parents with other mutations (RR, 0.39; 95% CI, 0.20–0.78; p =0.008). We could confirm that children with FH provide a better model to perform genotype–phenotype analyses. In particular, children with null alleles had significantly more elevated LDL cholesterol levels than carriers of other alleles but this was not associated with higher risk of CVD in the parents. Nonetheless, a specific LDL receptor mutation was associated with less deteriorated lipoprotein levels and a milder CVD risk. [Copyright &y& Elsevier]

Abstract: Objectives:: Paraoxonase (PON1) is a potent enzyme, physically associated with the high-density lipoprotein particle. PON1 may protect against cardiovascular disease (CVD), since it is capable of hydrolyzing oxidized LDL-cholesterol, thereby negating the detrimental effects of this lipoprotein on the arterial wall. Design and methods:: In 187 patients with familial hypercholesterolemia, we studied the seven most common single nucleotide polymorphisms (SNPs) in both the coding and promoter sequences of PON1 (L55M, Q192R, T-107C, C-126G, G-162A, G-824A, and C-907G) in terms of PON1 activity and intima media thickness (IMT) of the carotid arterial wall, a validated surrogate marker for CVD. Results:: In concordance with several previous studies, we observed that the L55M, T-107C, G-162A, G-824A, and C-907G SNPs conferred PON1 activity towards phenylacetate, while this was not the case for the Q192R and C-126G SNPs. Importantly, in a multivariate regression analysis, G-824A proved to be an independent predictor of carotid IMT. Additionally, the two fully discordant homozygous haplotypes, C-907/G-824/G-162/C-126/T-107/55M versus -907G/-824A/-162A/-126G/-107C/L55, differed by 22% in carotid IMT (P = 0.007). Conclusions:: Genetic variation at the PON1 locus has a strong influence on PON1 activity as well as on carotid IMT. These data indicate that PON1 is indeed involved in the pathogenesis of atherosclerosis. Whether this also translates into a role for PON1 in the occurrence of CVD events needs to be confirmed by large prospective studies in the general population. [Copyright &y& Elsevier]