Apolipoprotein B: Bridging the Gap Between Evidence and Clinical Practice.

Despite data suggesting that apolipoprotein B (apoB) measurement outperforms low-density lipoprotein cholesterol level measurement in predicting atherosclerotic cardiovascular disease risk, apoB measurement has not become widely adopted into routine clinical practice. One barrier for use of apoB measurement is lack of consistent guidance for clinicians on how to interpret and apply apoB results in clinical context. Whereas guidelines have often provided clear low-density lipoprotein cholesterol targets or triggers to initiate treatment change, consistent targets for apoB are lacking. In this review, we synthesize existing data regarding the epidemiology of apoB by comparing guideline recommendations regarding use of apoB measurement, describing population percentiles of apoB relative to low-density lipoprotein cholesterol levels, summarizing studies of discordance between low-density lipoprotein cholesterol and apoB levels, and evaluating apoB levels in clinical trials of lipid-lowering therapy to guide potential treatment targets. We propose evidence-guided apoB thresholds for use in cholesterol management and clinical care.

Association Between Patient Sex and Familial Hypercholesterolemia and Long-Term Cardiovascular Risk Factor Management 5 Years After Acute Coronary Syndrome.

BACKGROUND: Long-term control of cardiovascular risk factors after acute coronary syndrome (ACS) is the cornerstone for preventing recurrence. We investigated the extent of cardiovascular risk factor management in males and females with and without familial hypercholesterolemia (FH) 5 years after ACS. METHODS: We studied patients hospitalized for ACS between 2009 and 2017 in a Swiss multicenter prospective cohort study. FH was defined based on clinical criteria from the Dutch Lipid Clinic Network and Simon Broome definitions. Five years post-ACS, we assessed low-density lipoprotein-cholesterol (LDL-c) levels, lipid-lowering therapy (LLT), and other cardiovascular risk factors, comparing males to females with and without FH using generalized estimating equations. RESULTS: A total of 3139 patients were included; mean age was 61.4 years (SD, 12.1), 620 (19.8%) were female, and 747 (23.5%) had possible FH. Compared with males at 5-years post-ACS, females were more likely to not use statins (odds ratio, 1.61 [95% CI, 1.28-2.03]) and less likely to have combination LLT (odds ratio, 0.72 [95% CI, 0.55-0.93]), without difference between patients with FH and without FH. Females in both FH and non-FH groups less frequently reached LDL-c values ≤1.8 mmol/L (odds ratio, 0.78 [95% CI, 0.78-0.93]). Overall, patients with FH were more frequently on high-dose statins compared with patients without FH (51.0% versus 42.9%; P=0.001) and presented more frequently with a combination of 2 or more LLT compared with patients without FH (33.8% versus 17.7%; P<0.001), but less frequently reached LDL-c targets of ≤1.8 mmol/L (33.5% versus 44.3%; P<0.001) or ≤2.6 mmol/L (70.2% versus 78.1%; P=0.001). CONCLUSIONS: Five years after ACS, females had less intensive LLT and were less likely to reach target LDL-c levels than males, regardless of FH status. Males and females with FH had less optimal control of LDL-c despite more frequently taking high-dose statins or combination LLT compared with patients without FH. Long-term management of patients with ACS and FH, especially females, warrants optimization.

Identifying People at High Risk for Severe Aortic Stenosis: Aortic Valve Calcium Versus Lipoprotein(a) and Low-Density Lipoprotein Cholesterol.

BACKGROUND: Aortic valve calcification (AVC), Lp(a) [lipoprotein(a)], and low-density lipoprotein cholesterol (LDL-C) are associated with severe aortic stenosis (AS). We aimed to determine which of these risk factors were most strongly associated with the risk of incident severe AS. METHODS: A total of 6792 participants from the MESA study (Multi-Ethnic Study of Atherosclerosis) had computed tomography-quantified AVC, Lp(a), and LDL-C values at MESA visit 1 (2000-2002). We calculated the absolute event rate of incident adjudicated severe AS per 1000 person-years and performed multivariable adjusted Cox proportional hazards regression. RESULTS: The mean age was 62 years old, and 47% were women. Over a median 16.7-year follow-up, the rate of incident severe AS increased exponentially with higher AVC, regardless of Lp(a) or LDL-C values. Participants with AVC=0 had a very low rate of severe AS even with elevated Lp(a) ≥50 mg/dL (<0.1/1000 person-years) or LDL-C ≥130 mg/dL (0.1/1000 person-years). AVC >0 was strongly associated with severe AS when Lp(a) <50 mg/dL hazard ratio (HR) of 33.8 (95% CI, 16.4-70.0) or ≥50 mg/dL HR of 61.5 (95% CI, 7.7-494.2) and when LDL-C <130 mg/dL HR of 31.1 (95% CI, 14.4-67.1) or ≥130 mg/dL HR of 50.2 (95% CI, 13.2-191.9). CONCLUSIONS: AVC better identifies people at high risk for severe AS compared with Lp(a) or LDL-C, and people with AVC=0 have a very low long-term rate of severe AS regardless of Lp(a) or LDL-C level. These results suggest AVC should be the preferred prognostic risk marker to identify patients at high risk for severe AS, which may help inform participant selection for future trials testing novel strategies to prevent severe AS.

Connecting impaired fibrinolysis and dyslipidemia.

A State of the Art lecture entitled "Connecting Fibrinolysis and Dyslipidemia" was presented at the International Society on Thrombosis and Haemostasis Congress 2023. Hemostasis balances the consequences of blood clotting and bleeding. This balance relies on the proper formation of blood clots, as well as the breakdown of blood clots. The primary mechanism that breaks down blood clots is fibrinolysis, where the fibrin net becomes lysed and the blood clot dissolves. Dyslipidemia is a condition where blood lipid and lipoprotein levels are abnormal. Here, we review studies that observed connections between impaired fibrinolysis and dyslipidemia. We also summarize the different correlations between thrombosis and dyslipidemia in different racial and ethnic groups. Finally, we summarize relevant and new findings on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress. More studies are needed to investigate the mechanistic connections between impaired fibrinolysis and dyslipidemia and whether these mechanisms differ in racially and ethnically diverse populations.

Evolocumab Treatment in Pediatric Patients With Homozygous Familial Hypercholesterolemia: Pooled Data From Three Open-Label Studies.

BACKGROUND: Pediatric patients with homozygous familial hypercholesterolemia (HoFH) have an increased risk of atherosclerotic cardiovascular disease and difficulty meeting low-density lipoprotein cholesterol (LDL-C) goals. In this post hoc analysis, we evaluated pooled safety and efficacy data from 3 studies in pediatric patients with HoFH treated with the PCSK9 (proprotein convertase subtilisin/kexin type 9) monoclonal antibody inhibitor evolocumab. METHODS: Patients with HoFH aged 10 to 17 years received treatment with open-label evolocumab 420 mg subcutaneously monthly or biweekly in the TAUSSIG, RAMAN, or HAUSER-OLE clinical studies. All patients received background statins with or without ezetimibe. Study duration ranged from 12 to 260 weeks. The primary end point was treatment-emergent adverse events per 100 patient-years. Efficacy end points were changes from baseline to week 12 in lipids and PCSK9. RESULTS: Of the 39 patients in the pooled analysis, 69.2% were males, median age was 13.0 years, and 79.5% (31/39) had genotyped HoFH with LDLR pathogenic variants. Overall, median exposure to evolocumab was 18.2 (Q1, Q3: 3.0, 18.5) months. Treatment-emergent adverse events with an exposure-adjusted patient incidence rate of ≥5% were upper respiratory tract infection (6.6%), influenza (5.2%), and acne (5.0%) per 100 patient-years. Exposure-adjusted patient incidence of serious treatment-emergent adverse events was 13.3% per 100 patient-years. Excluding 4 patients receiving lipoprotein apheresis, week 12 median percentage change from baseline in LDL-C was -2.9% (Q1, Q3: -21.7, 1.5); however, 42.9% (15/35) of patients achieved ≥15% reduction in LDL-C from baseline. Residual LDLR (LDL receptor) activity was not associated with a reduction in LDL-C. CONCLUSIONS: In this pooled data analysis from 3 studies in pediatric patients with HoFH, evolocumab was well tolerated, with no new safety signals reported. These safety findings are consistent with findings from previous studies of evolocumab. Patients showed marked variability in LDL-C reduction. Results from this pooled analysis support guidelines suggesting a trial of PCSK9 inhibitor therapy regardless of estimated residual LDLR function. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01624142, NCT03403374, and NCT02624869.

The Significance of Lipoproteins in the Development of Obesity.

Disruption of lipoprotein metabolism plays an important role in the development of several cardiovascular, inflammatory, and metabolic diseases. This review examines the importance of different types of lipoproteins and the role they play in the development of dyslipidemia in obesity. The causes and consequences associated with the disruption of lipid metabolism and its significance in the pathogenesis of obesity are considered. The relationship between such pathological processes, which occur alongside obesity as dyslipidemia and inflammation, is determined. In view of the current efficacy and toxicity limitations of currently approved drugs, natural compounds as potential therapeutic agents in the treatment of obesity are considered in the review. The complex mechanisms of lipid metabolism normalization in obesity found for these compounds can serve as one of the confirmations of their potential efficacy in treating obesity. Nanoparticles can serve as carriers for the considered drugs, which can improve their pharmacokinetic properties.

Risk of Cardiovascular Disease according to Baseline Low-Density Lipoprotein Cholesterol Level in Different Age Groups in Korean Diabetes Population: A Cohort Study.

BACKGRUOUND: The association between low-density lipoprotein (LDL-C) levels and cardiovascular disease (CVD) risk in different age groups within the diabetes mellitus (DM) population remains unclear. The cohort study was conducted to investigate this relationship. METHODS: We assessed the 2009 to 2012 Korean National Health Screening and National Health Insurance Service records, with follow-up to the primary outcome (myocardial infarction [MI] or stroke) or December 2018. After excluding the participants with a history of MI or stroke, 2,227,394 participants with DM were included and categorized according to baseline LDL-C levels and age. Cox proportional hazards modeling was conducted. The CVD risk of age <40 years and LDL-C <70 mg/dL was set as the reference. In each age group, LDL-C <70 mg/dL was used as a reference for the subgroup analysis. RESULTS: The cut-off LDL-C value for increased MI risk in each age group varied (<40 years old, LDL-C ≥160 mg/dL: hazard ratios [HR], 2.03; 95% confidence interval [CI], 1.644 to 2.506) (40-49-year-old, LDL-C <115 mg/dL: HR, 1.245; 95% CI, 1.04 to 1.489) (50-59-year-old, LDL-C <115 mg/dL: HR, 1.21; 95% CI, 1.014 to 1.445) (60-69-year-old, LDL-C <145 mg/dL: HR, 1.229; 95% CI, 1.022 to 1.479) (≥70 years old group, LDL-C <100 mg/dL: HR, 1.238; 95% CI, 1.018 to 1.504). The cut-off LDL-C values for increased stroke risk varied in each age subgroup (<40 years old, LDL-C ≥160 mg/dL: HR, 1.395; 95% CI, 1.094 to 1.779) (40-49-year-old, LDL-C <145 mg/dL: HR, 1.13; 95% CI, 1.019 to 1.253) (50-59-year-old, LDL-C <160 mg/dL: HR, 1.079; 95% CI, 1.008 to 1.154) (60-69-year-old, LDL-C <130 mg/dL: HR, 1.07; 95% CI, 1.022 to 1.119) (≥70 years old, LDL-C <115 mg/dL: HR, 1.064; 95% CI, 1.019 to 1.112). CONCLUSION: The effect of LDL-C on the risk of CVD differs depending on the age of the population with DM.

EXPRESS: Effectiveness of HMG-CoA reductase inhibitors on inflammation and metabolic markers in the US-Mexico border Hispanic population.

HMG-CoA reductase inhibitors (statins) are commonly used for dyslipidemia management to reduce the risk of cardiovascular disease (CVD). High-sensitivity C-reactive protein (hs-CRP) is an emerging systematic low-grade inflammatory marker associated with atherosclerotic CVD development. Despite racial/ethnic disparities in the use and response of statins and the anti-inflammatory effects of statins, the effectiveness of statins on inflammation and metabolic markers is unknown among Hispanics. We performed a retrospective cohort study using 150 adult patients scheduled for an annual physical exam at a family medicine clinic between January 1, 2021, and December 31, 2021. Effect size with a 95% confidence interval (CI) was estimated using adjusted regression analyses. Among 150 patients, 52 (34.67%) received statins. Patients who received statins had significantly reduced median hs-CRP (1.9 vs. 3.2, p=0.007), mean low-density lipoprotein (LDL-C) (101.18 vs. 124.6, p<0.001), and total cholesterol (172.6 vs. 194.5, p<0.001) concentrations compared to those who did not receive statins. In the propensity-scores matched analysis, lower concentrations of log-transformed hs-CRP (regression coefficient [RC], -0.48; 95%CI: -0.89, -0.07), LDL-C (RC, -19.57; 95%CI: -33.04, -6.1), and total cholesterol (RC, -23.47; 95%CI: -38.96, -7.98) were associated with statin use. In addition, hepatic steatosis (adjusted relative risk [aRR]=0.25; 95%CI: 0.08, 0.78, p= 0.017) was significantly lower among patients with the use of statins. Our study suggests that HMG-CoA reductase inhibitors may help reduce inflammation among Hispanic patients with dyslipidemia and hypertension. These findings have useful implications for preventing risk and disparities associated with cardiovascular and other inflammatory-induced diseases among the fastest-growing US Hispanic minorities.

Efficacy, Safety, and Tolerability of Inclisiran in Patients With Homozygous Familial Hypercholesterolemia: Results From the ORION-5 Randomized Clinical Trial.

BACKGROUND: Homozygous familial hypercholesterolemia is a genetic disease characterized by extremely high levels of low-density lipoprotein cholesterol (LDL-C) and a high risk of premature cardiovascular events. The proof-of-concept study ORION-2 (A Study of Inclisiran in Participants With Homozygous Familial Hypercholesterolemia) showed that inclisiran, a small interfering RNA that prevents production of the hepatic PCSK9 protein (proprotein convertase subtilisin/kexin type 9), could lead to durable reductions in LDL-C levels when added to statins and ezetimibe in patients with homozygous familial hypercholesterolemia. METHODS: ORION-5 was a phase 3, 2-part, multicenter study in 56 patients with homozygous familial hypercholesterolemia and elevated LDL-C levels despite maximum tolerated doses of LDL-C-lowering therapies with or without lipoprotein apheresis. Patients eligible for part 1 (double-blind, 6 months) were randomized 2:1 to receive either 300 mg of inclisiran sodium (equivalent to 284 mg of inclisiran) or placebo. Placebo-treated patients from part 1 were transitioned to inclisiran in part 2 (open-label, 18 months). The primary end point was the percentage change in LDL-C levels from baseline to day 150. RESULTS: The mean age of the patients was 42.7 years, and 60.7% were women. The mean baseline LDL-C levels were 294.0 mg/dL and 356.7 mg/dL in the inclisiran and placebo groups, respectively. The placebo-corrected percentage change in LDL-C level from baseline to day 150 was -1.68% (95% CI, -29.19% to 25.83%; P=0.90), and the difference was not statistically significant between the inclisiran and placebo groups. The placebo-corrected percentage change in PCSK9 levels from baseline to day 150 was -60.6% with inclisiran treatment (P<0.0001); this was sustained throughout the study, confirming the effect of inclisiran on its biological target of PCSK9. No statistically significant differences between the inclisiran and placebo groups were observed in the levels of other lipids and lipoproteins (apolipoprotein B, total cholesterol, and non-high-density lipoprotein cholesterol). Adverse events and serious adverse events did not differ between the inclisiran and placebo groups throughout the study. CONCLUSIONS: Inclisiran treatment did not reduce LDL-C levels in patients with homozygous familial hypercholesterolemia despite substantial lowering of PCSK9 levels. Inclisiran was well-tolerated, and the safety findings were consistent with previously reported studies and the overall safety profile. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03851705.

Differences in Structural Changes and Pathophysiological Effects of Low-Density Lipoprotein Particles upon Accumulation of Acylhydroperoxy Derivatives in Their Outer Phospholipid Monolayer or upon Modification of Apoprotein B-100 by Natural Dicarbonyls.

Nanoparticles of the lipid-transporting system of the organism, low-density lipoproteins (LDL) of blood plasma, are prone to free radical peroxidation with formation of their main modified forms - oxidized LDL itself (containing hydroperoxy-acyls in phospholipids of the outer layer of particles) and dicarbonyl-modified LDL (apoprotein B-100 in which chemically modified via the Maillard reaction). Based on the study of free radical oxidation kinetics of LDLs, it was found that the existing in the literature designation of "oxidized lipoproteins" is incorrect because it does not reveal the nature of oxidative modification of LDLs. It was shown in this study that the "atherogenic" LDLs (particles of which are actively captured by the cultured macrophages) are not the oxidized LDL (in which LOOH-derivatives of phospholipids are formed by enzymatic oxidation by C-15 lipoxygenase of rabbit reticulocytes), but dicarbonyl-modified LDLs. Important role of the dicarbonyl-modified LDLs in the molecular mechanisms of atherogenesis and endothelial dysfunction is discussed.

lipoproteínas y colesterol total en adultos con colesterolemia normal y elevada en un policlínico de Lima-Perú 2022: Un estudio correlacional / Lipoproteins and total cholesterol in adults with normal and elevated cholesterolemia in a clinic in Lima-Peru 2022: A correlational study

RESUMEN Objetivo: Evaluar el grado de correlación entre las lipoproteínas de alta densidad, baja densidad, muy baja densidad y el colesterol total en pacientes con colesterolemia normal y alta. Metodología: Estudio observacional, analítico y transversal realizado desde enero a setiembre de 2022 con 207 pacientes mayores de 18 años, divididos en un grupo de colesterol normal y otro con hipercolesterolemia. Se realizó la prueba de correlación de Spearman. Resultados: En normocolesterolémicos, hubo una correlación baja y negativa entre lipoproteínas de alta densidad y las lipoproteínas de baja densidad (-0.263) así como entre lipoproteínas de alta densidad y las de muy baja densidad (-0.220). En hipercolesterolémicos, hubo una correlación baja y positiva entre lipoproteínas de alta densidad con colesterol total (0.344). En ambos grupos, hubo una correlación alta entre colesterol y lipoproteínas de baja densidad y baja y positiva entre colesterol y lipoproteínas de muy baja densidad. Conclusiones: Las lipoproteínas se correlacionan en normocolesterolémicos y las lipoproteínas de alta densidad se correlacionan en hipercolesterolémicos.

ABSTRACT Objective: To evaluate the degree of correlation between high-density, low-density, and very low-density lipoproteins and total cholesterol in patients with normal and high cholesterolemia. Methodology: Observational, analytical and cross-sectional study carried out from January to September 2022 with 207 patients over 18 years of age divided into a group with normal cholesterol and another with hypercholesterolemia. The Spearman correlation test was performed. Results: In normocholesterolemic subjects there was a low and negative correlation between high-density lipoproteins and low-density lipoproteins (-0.263) as well as between high-density lipoproteins and very low-density lipoproteins (-0.220). In hypercholesterolemic patients there was a low and positive correlation between high-density lipoproteins and total cholesterol (0.344). In both groups there was a high correlation between cholesterol and low-density lipoproteins and a low and positive correlation between cholesterol and very low-density lipoproteins. Conclusions: Lipoproteins are correlated in normocholesterolemics and high-density lipoproteins are correlated in hypercholesterolemics.

The benefits of measuring the size and number of lipoprotein particles for cardiovascular risk prediction: A systematic review and meta-analysis / Los beneficios de medir el tamaño y el número de partículas de lipoproteínas para la predicción del riesgo cardiovascular: una revisión sistemática y un metaanálisis

Objective: Cardiovascular risk (CVR) is conventionally calculated by measuring the total cholesterol content of high-density lipoproteins (HDL) and low-density lipoproteins (LDL). The purpose of this systematic review was to assess the CVR associated with LDL and HDL particle size and number as determined by nuclear magnetic resonance (NMR) spectroscopy. Material and methods: A literature search was performed using the electronic databases MEDLINE and Scopus. All cohort and case–control studies published before January 1, 2019 that met the following inclusion criteria were included: HDL-P, LDL-P, HDL-Z and/or LDL-Z measured by NMR spectroscopy; cardiovascular event as an outcome variable; risk of cardiovascular events expressed as odds ratios or hazard ratios; only adult patients. A meta-analysis was performed for each exposure variable (4 for LDL and 5 for HDL) and for each exposure measure (highest versus lowest quartile and 1-standard deviation increment). Results: This review included 24 studies. Number of LDL particles was directly associated with CVR: risk increased by 28% with each standard deviation increment. LDL particle size was inversely and significantly associated with CVR: each standard deviation increment corresponded to an 8% risk reduction. CVR increased by 12% with each standard deviation increase in number of small LDL particles. HD, particle number and size were inversely associated with CVR. Conclusion: Larger particle size provided greater protection, although this relationship was inconsistent between studies. Larger number of LDL particles and smaller LDL particle size are associated with increased CVR. Risk decreases with increasing number and size of HDL particles.(AU)

Objetivo: El riesgo cardiovascular (RCV) se calcula convencionalmente midiendo el contenido de colesterol total de las lipoproteínas de alta densidad (HDL) y las lipoproteínas de baja densidad (LDL). El propósito de esta revisión sistemática fue evaluar el RCV asociado con el tamaño y el número de partículas de LDL y HDL, según lo determinado por espectroscopia de resonancia magnética nuclear (RMN). Material y métodos: Se realizó una búsqueda bibliográfica utilizando las bases de datos electrónicas Medline y Scopus. Se incluyeron todos los estudios de cohortes y de casos y controles publicados antes del 1 de enero de 2019, que cumplieron con los siguientes criterios de inclusión: HDL-P, LDL-P, HDL-Z y/o LDL-Z medidos por espectroscopia de RMN; evento cardiovascular como variable de resultado; riesgo de eventos cardiovasculares expresado como cociente de posibilidades o cociente de riesgos instantáneos; solo pacientes adultos. Se realizó un metaanálisis para cada variable de exposición (cuatro para LDL y cinco para HDL) y para cada medida de exposición (cuartil más alto vs. más bajo e incremento de 1 desviación estándar [DE]). Resultados: Esta revisión incluyó 24 estudios. El número de partículas LDL se asoció directamente con el RCV: el riesgo aumentó 28% con cada incremento de la DE. El tamaño de las partículas de LDL se asoció inversa y significativamente con el RCV: cada incremento de la DE correspondió a una reducción del riesgo de 8%. El RCV aumentó 12% con cada aumento de la DE en el número de partículas pequeñas de LDL. HDL, número y tamaño de partículas se asociaron inversamente con CVR. Conclusión: El tamaño de partícula más grande proporcionó una mayor protección, aunque esta relación fue inconsistente entre los estudios. Un mayor número de partículas de LDL y un tamaño de partícula de LDL más pequeño se asocian con un aumento de la RCV. El riesgo disminuye con el aumento del número y tamaño de las partículas de HDL.(AU)

Adsorption of Acylhydroperoxy-Derivatives of Phospholipids from Biomembranes by Blood Plasma Lipoproteins.

It has been established that acylhydroperoxy derivatives of phospholipids from oxidized rat liver mitochondria are captured predominantly by LDL particles but not by HDL during co-incubation with blood plasma lipoproteins, which refutes the previously suggested hypothesis about the involvement of HDL in the reverse transport of oxidized phospholipids and confirms the possibility of different mechanisms of lipohydroperoxide accumulation in LDL during oxidative stress.

Effect of Total SMS Activity on LDL Catabolism in Mice.

BACKGROUND: Sphingomyelin (SM) and cholesterol are 2 key lipid partners on cell membranes and on lipoproteins. Many studies have indicated the influence of cholesterol on SM metabolism. This study examined the influence of SM biosynthesis on cholesterol metabolism. METHODS: Inducible global Sms1 KO (knockout)/global Sms2 KO mice were prepared to evaluate the effect of whole-body SM biosynthesis deficiency on lipoprotein metabolism. Tissue cholesterol, SM, ceramide, and glucosylceramide levels were measured. Triglyceride production rate and LDL (low-density lipoprotein) catabolism were measured. Lipid rafts were isolated and LDL receptor mass and function were evaluated. Also, the effects of exogenous sphingolipids on hepatocytes were investigated. RESULTS: We found that total SMS (SM synthase) depletion significantly reduced plasma SM levels. Also, the total deficiency significantly induced plasma cholesterol, apoB (apolipoprotein B), and apoE (apolipoprotein E) levels. Importantly, total SMS deficiency, but not SMS2 deficiency, dramatically decreased LDL receptors in the liver and attenuated LDL uptake through the receptor. Further, we found that total SMS deficiency greatly reduced LDL receptors in the lipid rafts, which contained significantly lower SM and significantly higher glucosylceramide, as well as cholesterol. Furthermore, we treated primary hepatocytes and Huh7 cells (a human hepatoma cell line) with SM, ceramide, or glucosylceramide, and we found that only SM could upregulate LDL receptor levels in a dose-dependent fashion. CONCLUSIONS: Whole-body SM biosynthesis plays an important role in LDL cholesterol catabolism. The total SMS deficiency, but not SMS2 deficiency, reduces LDL uptake and causes LDL cholesterol accumulation in the circulation. Given the fact that serum SM level is a risk factor for cardiovascular diseases, inhibiting SMS2 but not SMS1 should be the desirable approach.

New Loss-of-Function Mutations in PCSK9 Reduce Plasma LDL Cholesterol.

BACKGROUND: Lower plasma levels of LDL (low-density lipoprotein) cholesterol (LDL-C) can reduce the risk of atherosclerotic cardiovascular disease. The loss-of-function mutations in PCSK9 (proprotein convertase subtilisin/kexin type 9) have been known to associate with low LDL-C in many human populations. PCSK9 genetic variants in Chinese Uyghurs who are at high risk of atherosclerotic cardiovascular disease due to their dietary habits have not been reported. METHODS: The study involved the whole-exome and target sequencing of college students from Uyghur and other ethnic groups in Xinjiang, China, for the association of PCSK9 loss-of-function mutations with low plasma levels of LDL-C. The mechanisms by which the identified mutations affect the function of PCSK9 were investigated in cultured cells using biochemical and cell assays. The causal effects of the identified PCSK9 mutations on LDL-C levels were verified in mice injected with adeno-associated virus expressing different forms of PCSK9 and fed a high-cholesterol diet. RESULTS: We identified 2 PCSK9 mutations-E144K and C378W-in Chinese Uyghurs with low plasma levels of LDL-C. The E144K and C378W mutations impaired the maturation and secretion of the PCSK9 protein, respectively. Adeno-associated virus-mediated expression of E144K and C378W mutants in Pcsk9 KO (knockout) mice fed a high-cholesterol diet also hampered PCSK9 secretion into the serum, resulting in elevated levels of LDL receptor in the liver and reduced levels of LDL-C in the serum. CONCLUSIONS: Our study shows that E144K and C378W are PCSK9 loss-of-function mutations causing low LDL-C levels in mice and probably in humans as well.

Beneficial Effect of Cuban Policosanol on Blood Pressure and Serum Lipoproteins Accompanied with Lowered Glycated Hemoglobin and Enhanced High-Density Lipoprotein Functionalities in a Randomized, Placebo-Controlled, and Double-Blinded Trial with Healthy Japanese.

This study evaluated the efficacy and safety of 20 mg of Cuban policosanol in blood pressure (BP) and lipid/lipoprotein parameters of healthy Japanese subjects via a placebo-controlled, randomized, and double-blinded human trial. After 12 weeks of consumption, the policosanol group showed significantly lower BP, glycated hemoglobin (HbA1c), and blood urea nitrogen (BUN) levels. The policosanol group also showed lower aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl transferase (γ-GTP) levels at week 12 than those at week 0: A decrease of up to 9% (p < 0.05), 17% (p < 0.05), and 15% (p < 0.05) was observed, respectively. The policosanol group showed significantly higher HDL-C level and HDL-C/TC (%), approximately 9.5% (p < 0.001) and 7.2% (p = 0.003), respectively, than the placebo group and a difference in the point of time and group interaction (p < 0.001). In lipoprotein analysis, the policosanol group showed a decrease in oxidation and glycation extent in VLDL and LDL with an improvement of particle shape and morphology after 12 weeks. HDL from the policosanol group showed in vitro stronger antioxidant and in vivo anti-inflammatory abilities. In conclusion, 12 weeks of Cuban policosanolconsumption in Japanese subjects showed significant improvement in blood pressure, lipid profiles, hepatic functions, and HbA1c with enhancement of HDL functionalities.

Association Between Achieved Low-Density Lipoprotein Cholesterol Levels and Long-Term Cardiovascular and Safety Outcomes: An Analysis of FOURIER-OLE.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is a well-established risk factor for atherosclerotic cardiovascular disease. However, the optimal achieved LDL-C level with regard to efficacy and safety in the long term remains unknown. METHODS: In FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk), 27 564 patients with stable atherosclerotic cardiovascular disease were randomized to evolocumab versus placebo, with a median follow-up of 2.2 years. In the open-label extension (FOURIER-OLE), 6635 of these patients were transitioned to open-label evolocumab regardless of initial treatment allocation in the parent trial and were followed for an additional median of 5 years. In this prespecified analysis, we examined the relationship between achieved LDL-C levels (an average of the first 2 LDL-C levels measured) in FOURIER-OLE (available in 6559 patients) and the incidence of subsequent cardiovascular and safety outcomes. We also performed sensitivity analyses evaluating cardiovascular and safety outcomes in the entire FOURIER and FOURIER-OLE patient population. Multivariable modeling was used to adjust for baseline factors associated with achieved LDL-C levels. RESULTS: In FOURIER-OLE, 1604 (24%), 2627 (40%), 1031 (16%), 486 (7%), and 811 (12%) patients achieved LDL-C levels of <20, 20 to <40, 40 to <55, 55 to <70, and ≥70 mg/dL, respectively. There was a monotonic relationship between lower achieved LDL-C levels-down to very low levels <20 mg/dL-and a lower risk of the primary efficacy end point (composite of cardiovascular death, myocardial infarction, stroke, hospital admission for unstable angina or coronary revascularization) and the key secondary efficacy end point (composite of cardiovascular death, myocardial infarction, or stroke) that persisted after multivariable adjustment (adjusted Ptrend<0.0001 for each end points). No statistically significant associations existed in the primary analyses between lower achieved LDL-C levels and increased risk of the safety outcomes (serious adverse events, new or recurrent cancer, cataract-related adverse events, hemorrhagic stroke, new-onset diabetes, neurocognitive adverse events, muscle-related events, or noncardiovascular death). Similar findings were noted in the entire FOURIER and FOURIER-OLE cohort up to a maximum follow-up of 8.6 years. CONCLUSIONS: In patients with atherosclerotic cardiovascular disease, long-term achievement of lower LDL-C levels, down to <20 mg/dL (<0.5 mmol/L), was associated with a lower risk of cardiovascular outcomes with no significant safety concerns. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01764633.