Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Membranes (Basel) ; 12(11)2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36422126

ABSTRACT

Cell membrane lipid composition, especially cholesterol, affects many functions of embedded enzymes, transporters and receptors in red blood cells (RBC). High membrane cholesterol content affects the RBCs' main vital function, O2 and CO2 transport and delivery, with consequences on peripheral tissue physiology and pathology. A high degree of deformability of RBCs is required to accommodate the size of micro-vessels with diameters significantly lower than RBCs. The potential therapeutic role of high-density lipoproteins (HDL) in the removal of cholesterol and its activity regarding maintenance of an optimal concentration of RBC membrane cholesterol have not been well investigated. On the contrary, the focus for HDL research has mainly been on the clearance of cholesterol accumulated in atherosclerotic macrophages and plaques. Since all interventions aiming at decreasing cardiovascular diseases by increasing the plasma level of HDL cholesterol have failed so far in large outcome studies, we reviewed the potential role of HDL to remove excess membrane cholesterol from RBC, especially in sickle cell disease (SCD). Indeed, abundant literature supports a consistent decrease in cholesterol transported by all plasma lipoproteins in SCD, in addition to HDL, low- (LDL) and very low-density lipoproteins (VLDL). Unexpectedly, these decreases in plasma were associated with an increase in RBC membrane cholesterol. The concentration and activity of the main enzyme involved in the removal of cholesterol and generation of large HDL particles-lecithin cholesterol ester transferase (LCAT)-are also significantly decreased in SCD. These observations might partially explain the decrease in RBC deformability, diminished gas exchange and tendency of RBCs to aggregate in SCD. We showed that incubation of RBC from SCD patients with human HDL or the HDL-mimetic peptide Fx5A improves the impaired RBC deformability and decreases intracellular reactive oxygen species levels. We propose that the main physiological role of HDL is to regulate the cholesterol/phospholipid ratio (C/PL), which is fundamental to the transport of oxygen and its delivery to peripheral tissues.

2.
Clin Drug Investig ; 37(5): 483-491, 2017 May.
Article in English | MEDLINE | ID: mdl-28213743

ABSTRACT

BACKGROUND: CER-001 comprises recombinant human apolipoprotein A-I complexed with phospholipids that mimics natural, nascent, pre-ß high-density lipoprotein (HDL). We present animal model data showing dose-dependent increases in cholesterol efflux with CER-001 and its subsequent elimination by reverse lipid transport, together with inhibition of atherosclerotic plaque progression. We report the first phase I study results with CER-001 in humans, starting at 0.25 mg/kg, which is 1/80th of the safe dose (20 mg/kg) established in 4-week multiple-dose animal studies dosed every second day. METHODS: Healthy volunteers, 18-55 years old with a low-density lipoprotein-cholesterol:HDL-cholesterol ratio greater than 3.0, received single intravenous escalating doses of CER-001 (0.25-45.0 mg/kg) and placebo in a double-blind randomised cross-over fashion. Subjects were followed up for 3 weeks post-dose. Assessments included adverse event monitoring, blood sampling, and clinical laboratory measurements. RESULTS: Thirty-two subjects were enrolled. All CER-001 doses (0.25-45 mg/kg) were safe and well tolerated, with an adverse event profile similar to placebo. Effects on clinical chemistry, haematology and coagulation parameters were comparable to placebo. No adverse effects of CER-001 on electrocardiograms were observed. No antibodies to apolipoprotein A-I were detected following single-dose administration of CER-001. Plasma apolipoprotein A-I levels increased in a dose-related manner and returned to baseline by 24 h post-dose for doses up to 10 mg/kg but remained in circulation for >72 h post-dose for doses >10 mg/kg. CER-001 caused elevations in plasma cholesterol and total and unesterified cholesterol in the HDL fraction. Mobilisation of unesterified cholesterol in the HDL fraction was seen with CER-001 at doses as low as 2 mg/kg. CONCLUSION: CER-001 is well tolerated when administered to humans as single doses up to 45 mg/kg and mobilises and eliminates cholesterol via reverse lipid transport.


Subject(s)
Apolipoprotein A-I/blood , Apolipoprotein A-I/therapeutic use , Cholesterol/blood , Phospholipids/therapeutic use , Recombinant Proteins/therapeutic use , Adult , Animals , Apolipoprotein A-I/pharmacology , Cholesterol, HDL/antagonists & inhibitors , Cholesterol, HDL/blood , Cholesterol, LDL/antagonists & inhibitors , Cholesterol, LDL/blood , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Drug Evaluation, Preclinical/methods , Female , Humans , Male , Mice , Mice, Knockout , Middle Aged , Phospholipids/pharmacology , Rabbits , Recombinant Proteins/pharmacology
3.
Cardiovasc Drugs Ther ; 29(6): 563-572, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26619842

ABSTRACT

Adenylyl cyclase 9 (ADCY9) mediates ß2-adrenoceptor (ß2-AR) signalling. Both proteins are associated with caveolae, specialized cholesterol-rich membrane substructures. Apolipoprotein A1 (ApoA1), the major protein component of high-density lipoprotein (HDL), removes cholesterol from cell membrane and caveolae and may thereby influence ß2-AR signalling, shown in vitro to be modulated by cholesterol. Patients with Sickle Cell Disease (SCD) typically have low HDL and ApoA1 levels. In patients, mainly of African origin, with SCD, ß2-AR activation may trigger adhesion of red blood cells to endothelial cells, leading to vascular occlusive events. Moreover, ADCY9 polymorphism is associated with risk of stroke in SCD. In recent clinical trials, ADCY9 polymorphism was found to be a discriminant factor associated with the risk of cardiovascular (CV) events in Caucasian patients treated with the HDL-raising compound dalcetrapib. We hypothesize that these seemingly disparate observations share a common mechanism related to interaction of HDL/ApoA1 and ADCY9 on ß2-AR signalling. This review also raises the importance of characterizing polymorphisms that determine the response to HDL-raising and -mimicking agents in the non-Caucasian population at high risk of CV diseases and suffering from SCD. This may facilitate personalized CV treatments.

4.
J Clin Lipidol ; 9(4): 568-75, 2015.
Article in English | MEDLINE | ID: mdl-26228675

ABSTRACT

BACKGROUND: The condensation of palmitoyl-CoA and L-Serine is the first step in the de novo formation of sphingolipids and catalyzed by the serine-palmitoyltransferase (SPT). Besides other acyl-CoAs the SPT can also metabolize L-alanine and glycine, which forms an atypical category of neurotoxic 1-deoxy-sphingolipids (1-deoxySL). Several mutations in SPT are associated with pathologically increased 1-deoxySL levels, which cause the inherited sensory neuropathy HSAN1. 1-DeoxySL levels are also elevated in individuals with the metabolic syndrome and diabetes mellitus type II and seem to be involved in the pathology of the diabetic neuropathy. OBJECTIVE: In previous studies, we observed a strong correlation between plasma 1-deoxySLs and triglycerides (TGs). We were therefore interested whether lowering plasma TG levels also affects plasma sphingolipid and in particular, 1-deoxySL levels. METHODS: Sixty-six patients with dyslipidemia were treated for 6 wk with the TG-lowering drug fenofibrate (160 mg/d) or extended-release niacin (0.5 g/d for 3 wk, then 1 g/d) with 4 wk of washout between treatments. The sphingoid base profile was analyzed by liquid chromatography-mass spectrometry (LC-MS) before and after each treatment block. RESULTS: Fenofibrate significantly lowered 1-deoxySLs and other atypical sphingoid bases (P < .001) but had no effect on the typical sphingolipids. In contrast, extended-release niacin had no effect on 1-deoxySL levels although both treatments lowered plasma TG levels. CONCLUSIONS: The lowering of plasma 1-deoxySL levels by fenofibrate in dyslipidemic patients might be a novel therapeutic approach in the prevention and treatment of diabetic neuropathy.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetic Neuropathies/drug therapy , Fenofibrate/administration & dosage , Hereditary Sensory and Autonomic Neuropathies/drug therapy , Sphingolipids/blood , Aged , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetic Neuropathies/blood , Diabetic Neuropathies/pathology , Female , Hereditary Sensory and Autonomic Neuropathies/blood , Hereditary Sensory and Autonomic Neuropathies/pathology , Humans , Male , Middle Aged , Mutation , Niacin/administration & dosage , Triglycerides/blood
5.
Vascul Pharmacol ; 74: 80-86, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26133666

ABSTRACT

BACKGROUND: Fibrates and niacin are at present the most effective therapies to increase plasma levels of high density lipoprotein-cholesterol (HDL-C); to date, limited data are available on their effects on HDL protective functions. METHODS AND RESULTS: Within a multicenter, randomized, open-label, cross-over study, 37 patients with metabolic syndrome received 6weeks' treatment with fenofibrate or extended-release niacin (ER niacin), with a 4weeks' wash-out period. HDL ability to preserve endothelial cell homeostasis was assessed by incubating cultured endothelial cells with HDL isolated from patients at baseline and after each treatment. HDL isolated from patients at baseline were as effective as control HDL in inhibiting vascular cell adhesion molecule-1 (VCAM-1) expression, but less efficient in promoting endothelial cell nitric oxide (NO) release. Both fenofibrate and ER niacin increased HDL ability to inhibit TNFα-induced VCAM-1 expression (+7% and +11%, respectively). Fenofibrate and ER niacin also improved the impaired HDL ability to induce the expression of endothelial nitric oxide synthase and NO production (+10% and +8%, respectively). Interestingly, HDL isolated after treatment showed an ability to promote endothelial NO release similar to HDL isolated from controls. No differences were observed between the two drugs. With both drugs, HDL function was improved irrespective of baseline HDL-C levels. CONCLUSION: Treatment with fenofibrate or ER niacin in patients with metabolic syndrome not only increased HDL-C levels but also improved the endothelial protective effects of HDL.


Subject(s)
Cholesterol, HDL/blood , Delayed-Action Preparations/therapeutic use , Endothelial Cells/drug effects , Fenofibrate/therapeutic use , Metabolic Syndrome/drug therapy , Niacin/therapeutic use , Protective Agents/therapeutic use , Cells, Cultured , Cross-Over Studies , Endothelial Cells/metabolism , Female , Humans , Hypolipidemic Agents/therapeutic use , Male , Metabolic Syndrome/blood , Metabolic Syndrome/metabolism , Middle Aged , Nitric Oxide Synthase Type III/metabolism , Vascular Cell Adhesion Molecule-1/metabolism
6.
Arch Med Res ; 46(5): 361-71, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26009249

ABSTRACT

The main atheroprotective mechanism of high-density lipoprotein (HDL) has been regarded as reverse cholesterol transport, whereby cholesterol from peripheral tissues is removed and transported to the liver for elimination. Although numerous additional atheroprotective mechanisms have been suggested, the role of HDL in modulating signal transduction of cell membrane-bound receptors has received little attention to date. This potential was recently highlighted following the identification of a polymorphism in the adenylyl cyclase 9 gene (ADCY9) that was shown to be a determining factor in the risk of cardiovascular (CV) events in patients treated with the HDL-raising compound dalcetrapib. Indeed, ADCY9 is part of the signaling pathway of the ß2-adrenergic receptor (ß2-AR) and both are membrane-bound proteins affected by changes in membrane-rich cholesterol plasma membrane domains (caveolae). Numerous G-protein-coupled receptors (GPCRs) and ion channels are affected by caveolae, with caveolae composition acting as a 'signalosome'. Polymorphisms in the genes encoding ADCY9 and ß2-AR are associated with response to ß2-agonist drugs in patients with asthma, malaria and with sickle cell disease. Crystallization of the ß2-AR has found cholesterol tightly bound to transmembrane structures of the receptor. Cholesterol has also been shown to modulate the activity of this receptor. Apolipoprotein A1 (ApoA1), the major protein component of HDL, destabilizes and removes cholesterol from caveolae with high affinity through interaction with ATP-binding cassette transporter. Furthermore, ß2-AR activity may be affected by ApoA1/HDL-targeted therapies. Taken together, these observations suggest a common pathway that potentially links a primary HDL function to the regulation of signal transduction.


Subject(s)
Cardiovascular Diseases/genetics , Cardiovascular Diseases/physiopathology , Lipoproteins, HDL/metabolism , Receptors, Adrenergic, beta-2/metabolism , Signal Transduction/physiology , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Adenylyl Cyclases/genetics , Apolipoprotein A-I/metabolism , Cardiovascular Diseases/metabolism , Carrier Proteins/metabolism , Caveolae/metabolism , Cholesterol/metabolism , Humans , Membrane Proteins/metabolism , Polymorphism, Genetic
7.
Clin Chim Acta ; 447: 16-22, 2015 Jul 20.
Article in English | MEDLINE | ID: mdl-25979692

ABSTRACT

BACKGROUND: Biomarkers are a promising tool for the management of patients with atherosclerosis, but their variation is largely unknown. We assessed within-subject and between-subject biological variation of biomarkers in peripheral artery disease (PAD) patients and healthy controls, and defined which biomarkers have a favorable variation profile for future studies. METHODS: Prospective, parallel-group cohort study, including 62 patients with stable PAD (79% men, 65±7years) and 18 healthy control subjects (44% men, 57±7years). Blood samples were taken at baseline, and after 3-, 6-, and 12-months. We calculated within-subject (CVI) and between-subject (CVG) coefficients of variation and intra-class correlation coefficient (ICC). RESULTS: Mean levels of D-dimer, hs-CRP, IL-6, IL-8, MMP-9, MMP-3, S100A8/A9, PAI-1, sICAM-1, and sP-selectin levels were higher in PAD patients than in healthy controls (P≤.05 for all). CVI and CVG of the different biomarkers varied considerably in both groups. An ICC≥0.5 (indicating moderate-to-good reliability) was found for hs-CRP, D-Dimer, E-selectin, IL-10, MCP-1, MMP-3, oxLDL, sICAM-1 and sP-selectin in both groups, for sVCAM in healthy controls and for MMP-9, PAI-1 and sCD40L in PAD patients. CONCLUSIONS: Single biomarker measurements are of limited utility due to large within-subject variation, both in PAD patients and healthy subjects. D-dimer, hs-CRP, MMP-9, MMP-3, PAI-1, sP-selectin and sICAM-1 are biomarkers with both higher mean levels in PAD patients and a favorable variation profile making them most suitable for future studies.


Subject(s)
Peripheral Arterial Disease/blood , Aged , Biomarkers/blood , Case-Control Studies , Cohort Studies , Female , Humans , Male , Middle Aged , Prospective Studies
8.
Heart ; 101(11): 847-53, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25872524

ABSTRACT

CONTEXT: Epidemiological evidence that the risk of coronary heart disease is inversely associated with the level of high-density lipoprotein cholesterol (HDL-C) has motivated several phase III programmes with cholesteryl ester transfer protein (CETP) inhibitors. OBJECTIVES: To assess alternative methods to predict clinical response of CETP inhibitors. METHODS: Meta-regression analysis on raising HDL-C drugs (statins, fibrates, niacin) in randomised controlled trials. RESULTS: 51 trials in secondary prevention with a total of 167,311 patients for a follow-up >1 year where HDL-C was measured at baseline and during treatment. The meta-regression analysis showed no significant association between change in HDL-C (treatment vs comparator) and log risk ratio (RR) of clinical endpoint (non-fatal myocardial infarction or cardiac death). CETP inhibitors data are consistent with this finding (RR: 1.03; P5-P95: 0.99-1.21). A prespecified sensitivity analysis by drug class suggested that the strength of relationship might differ between pharmacological groups. A significant association for both statins (p<0.02, log RR=-0.169-0.0499*HDL-C change, R(2)=0.21) and niacin (p=0.02, log RR=1.07-0.185*HDL-C change, R(2)=0.61) but not fibrates (p=0.18, log RR=-0.367+0.077*HDL-C change, R(2)=0.40) was shown. However, the association was no longer detectable after adjustment for low-density lipoprotein cholesterol for statins or exclusion of open trials for niacin. CONCLUSIONS: Meta-regression suggested that CETP inhibitors might not influence coronary risk. The relation between change in HDL-C level and clinical endpoint may be drug dependent, which limits the use of HDL-C as a surrogate marker of coronary events. Other markers of HDL function may be more relevant.


Subject(s)
Cholesterol Ester Transfer Proteins/antagonists & inhibitors , Cholesterol, HDL/drug effects , Coronary Disease/prevention & control , Fibric Acids/therapeutic use , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Niacin/therapeutic use , Randomized Controlled Trials as Topic , Regression Analysis , Secondary Prevention , Treatment Outcome
9.
Cardiovasc Drugs Ther ; 29(1): 7-14, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25749868

ABSTRACT

PURPOSE: Cholesterol efflux from macrophages to HDL, measured in vitro, is augmented by treatment with agents which raise HDL cholesterol. In vitro, cholesterol depletion by statins is known to trigger a positive feedback on the cholesterol synthetic pathway via sterol regulatory element-binding protein (SREBP) transcription and changes in expression of SREBP regulated genes including microRNA33 (miR33) which is co-transcribed with SREBP and down-regulates ABCA1 and ABCG1 expression. METHODS: We investigated whether miR33 up-regulation, associated with SREBP increased transcription by statins, reduces macrophage ATP-binding cassette (ABC) transporter expression, thereby decreasing HDL-mediated cholesterol efflux at the tissue level. RESULTS: In human macrophage THP-1 cells cholesterol-loaded with acetylated LDL, incubation with 1 µM atorvastatin increased miR33 by 33 % (P < 0.05), and decreased ABCA1 messenger RNA (mRNA) and ABCG1 mRNA by 47 % (P < 0.05) and 27 % (NS), respectively. In J774A.1 mouse macrophage, labelled with 3H-cholesterol, ABCA1 mRNA and ABCA1-mediated cholesterol efflux were decreased by 1 µM statin: simvastatin > pitavastatin > atorvastatin > rosuvastatin > pravastatin. HDL incubated with rhCETP and dalcetrapib increased ABCA1-mediated cholesterol efflux. However, incremental simvastatin concentrations decreased cholesterol efflux to HDL treated with rhCETP and dalcetrapib. When HDL was incubated with rhCETP, addition of dalcetrapib augmented ABCA1-mediated cholesterol efflux from J774A.1 macrophages. However, simvastatin ≥1 µM virtually eliminated any HDL-ABCA1-mediated cholesterol efflux and any augmentation of that process by dalcetrapib. CONCLUSIONS: In vitro, statins increase miR33 expression, and decrease ABCA1 expression and cholesterol efflux from peripheral tissues; this may counteract the potential benefit of agents that raise HDL and apolipoprotein A-I in statin-treated patients.


Subject(s)
ATP Binding Cassette Transporter 1/metabolism , Cholesterol/metabolism , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Lipoproteins, HDL/metabolism , MicroRNAs/metabolism , Simvastatin/pharmacology , ATP Binding Cassette Transporter 1/genetics , ATP Binding Cassette Transporter, Subfamily G, Member 1 , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Animals , Cell Line , Humans , Mice , RNA, Messenger/metabolism , Receptors, LDL/genetics
10.
J Cardiovasc Pharmacol ; 65(6): 611-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25714598

ABSTRACT

Inclacumab, a novel monoclonal antibody against P-selectin in development for the treatment and prevention of atherosclerotic cardiovascular diseases, was administered in an ascending single-dose study as intravenous infusion to evaluate safety, pharmacokinetics, and pharmacodynamics. Fifty-six healthy subjects were enrolled in this randomized, double-blind placebo-controlled study. Each dose level (0.03-20 mg/kg) was investigated in separate groups of 8 subjects (6 on inclacumab, 2 on placebo). Platelet-leukocyte aggregates, free/total soluble P-selectin concentration ratio, drug concentrations, bleeding time, platelet aggregation, antibody formation, and routine laboratory parameters were measured frequently until 32 weeks. Pharmacokinetic profiles were indicative of target-mediated drug disposition. Platelet-leukocyte aggregate inhibition and soluble P-selectin occupancy showed dose dependency and were strongly correlated to inclacumab plasma concentrations, with IC50 of 740 and 4600 ng/mL, respectively. Inclacumab was well tolerated by the majority of subjects and did neither affect bleeding time nor platelet aggregation. These findings allowed the investigation of the potential beneficial therapeutic use of inclacumab in patient study.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Cardiovascular Agents/administration & dosage , P-Selectin/antagonists & inhibitors , Adult , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/blood , Antibodies, Monoclonal/pharmacokinetics , Bleeding Time , Cardiovascular Agents/adverse effects , Cardiovascular Agents/blood , Cardiovascular Agents/pharmacokinetics , Double-Blind Method , England , Female , Healthy Volunteers , Hemorrhage/chemically induced , Humans , Infusions, Intravenous , Male , Middle Aged , P-Selectin/immunology , Platelet Aggregation/drug effects , Predictive Value of Tests , Risk Assessment , Young Adult
11.
Circ Cardiovasc Genet ; 8(2): 372-82, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25583994

ABSTRACT

BACKGROUND: Dalcetrapib did not improve clinical outcomes, despite increasing high-density lipoprotein cholesterol by 30%. These results differ from other evidence supporting high-density lipoprotein as a therapeutic target. Responses to dalcetrapib may vary according to patients' genetic profile. METHODS AND RESULTS: We conducted a pharmacogenomic evaluation using a genome-wide approach in the dal-OUTCOMES study (discovery cohort, n=5749) and a targeted genotyping panel in the dal-PLAQUE-2 imaging trial (support cohort, n=386). The primary endpoint for the discovery cohort was a composite of cardiovascular events. The change from baseline in carotid intima-media thickness on ultrasonography at 6 and 12 months was evaluated as supporting evidence. A single-nucleotide polymorphism was found to be associated with cardiovascular events in the dalcetrapib arm, identifying the ADCY9 gene on chromosome 16 (rs1967309; P=2.41×10(-8)), with 8 polymorphisms providing P<10(-6) in this gene. Considering patients with genotype AA at rs1967309, there was a 39% reduction in the composite cardiovascular endpoint with dalcetrapib compared with placebo (hazard ratio, 0.61; 95% confidence interval, 0.41-0.92). In patients with genotype GG, there was a 27% increase in events with dalcetrapib versus placebo. Ten single-nucleotide polymorphism in the ADCY9 gene, the majority in linkage disequilibrium with rs1967309, were associated with the effect of dalcetrapib on intima-media thickness (P<0.05). Marker rs2238448 in ADCY9, in linkage disequilibrium with rs1967309 (r(2)=0.8), was associated with both the effects of dalcetrapib on intima-media thickness in dal-PLAQUE-2 (P=0.009) and events in dal-OUTCOMES (P=8.88×10(-8); hazard ratio, 0.67; 95% confidence interval, 0.58-0.78). CONCLUSIONS: The effects of dalcetrapib on atherosclerotic outcomes are determined by correlated polymorphisms in the ADCY9 gene. CLINICAL TRIAL INFORMATION: URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00658515 and NCT01059682.


Subject(s)
Adenylyl Cyclases/genetics , Atherosclerosis , Chromosomes, Human, Pair 16/genetics , Linkage Disequilibrium , Pharmacogenetics , Polymorphism, Genetic , Sulfhydryl Compounds/administration & dosage , Aged , Amides , Atherosclerosis/diagnostic imaging , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Carotid Intima-Media Thickness , Esters , Female , Humans , Male , Middle Aged
12.
J Clin Lipidol ; 7(5): 414-22, 2013.
Article in English | MEDLINE | ID: mdl-24079282

ABSTRACT

BACKGROUND: The effectiveness of therapies that raise high-density lipoprotein cholesterol (HDL-C) to lower cardiovascular disease risk is currently under debate, and further research into the relationship between HDL-C and function is required. OBJECTIVE: o investigate whether 2 established HDL-C-raising therapies had differential effects on parameters of high-density lipoprotein (HDL) quality and function, such as HDL particle profile and cholesterol efflux capacity (CEC), in patients with dyslipidemia. METHODS AND RESULTS: Sixty-six patients with dyslipidemia, 24 with low HDL-C levels (<40 mg/dL) and 42 with normal HDL-C levels (40-59 mg/dL), were treated for 6 weeks with fenofibrate (160 mg/d) or extended-release (ER) niacin (0.5 g/d for 3 weeks, then 1 g/d) with 4 weeks of washout between treatments. Lipoprotein particle size distribution was determined using nuclear magnetic resonance, and pathway-specific serum CECs were assessed in J774 macrophages, hepatoma, and Chinese hamster ovary-human adenosine triphosphate-binding cassette transporter G1 cells. Comparable increases in HDL-C and apolipoprotein A-I levels were seen with fenofibrate and ER niacin. There was a shift toward larger HDL, predominantly to medium-size HDL particles for fenofibrate (+209%) and to large HDL particles for ER niacin (+221%). Minor changes in serum CECs were observed with fenofibrate and ER niacin for all the efflux pathways measured. Small increases in plasma cholesteryl ester transfer protein and lecithin: cholesterol acyltransferase concentrations, and decreases in cholesteryl ester transfer protein activity were seen with both drugs. CONCLUSIONS: Fenofibrate and ER niacin increased plasma HDL-C level similarly, but modulated HDL particle size distribution differently; however, these changes did not result in differential effects on serum CECs.


Subject(s)
Cholesterol, HDL/chemistry , Cholesterol, HDL/metabolism , Dyslipidemias/drug therapy , Dyslipidemias/metabolism , Fenofibrate/pharmacology , Niacin/administration & dosage , Niacin/pharmacology , Particle Size , Adolescent , Adult , Aged , Animals , Biological Transport/drug effects , CHO Cells , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cholesterol, LDL/chemistry , Cholesterol, LDL/metabolism , Cricetinae , Cricetulus , Dyslipidemias/blood , Dyslipidemias/enzymology , Female , Fenofibrate/adverse effects , Fenofibrate/therapeutic use , Humans , Hypolipidemic Agents/adverse effects , Hypolipidemic Agents/pharmacology , Hypolipidemic Agents/therapeutic use , Male , Middle Aged , Niacin/adverse effects , Niacin/therapeutic use , Phosphatidylcholine-Sterol O-Acyltransferase/blood , Safety , Triglycerides/blood , Young Adult
13.
Lipids ; 48(12): 1185-96, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24068631

ABSTRACT

Fenofibrate and extended-release (ER) niacin similarly raise high-density lipoprotein cholesterol (HDL-C) concentration but their effects on levels of potent plasma antioxidant xanthophylls (lutein and zeaxanthin) and phytosterols obtained from dietary sources, and any relationship with plasma lipoproteins and pre-ß1-HDL levels, have not been investigated. We studied these parameters in 66 dyslipidemic patients treated for 6 week with fenofibrate (160 mg/day) or ER-niacin (0.5 g/day for 3 week, then 1 g/day) in a cross-over study. Both treatments increased HDL-C (16 %) and apolipoprotein (apo) A-I (7 %) but only fenofibrate increased apoA-II (28 %). Lutein and zeaxanthin levels were unaffected by fenofibrate but inversely correlated with percentage change in apoB and low-density lipoprotein cholesterol and positively correlated with end of treatment apoA-II. ApoA-II in isolated HDL in vitro bound more lutein than apoA-I. Xanthophylls were increased by ER-niacin (each ~30 %) without any correlation to lipoprotein or apo levels. Only fenofibrate markedly decreased plasma markers of cholesterol absorption; pre-ß1-HDL was significantly decreased by fenofibrate (-19 %, p < 0.0001), with little change (3.4 %) for ER-niacin. Although fenofibrate and ER-niacin similarly increased plasma HDL-C and apoA-I, effects on plasma xanthophylls, phytosterols and pre-ß1-HDL differed markedly, suggesting differences in intestinal lipidation of HDL. In addition, the in vitro investigations suggest an important role of plasma apoA-II in xanthophyll metabolism.


Subject(s)
Fenofibrate/therapeutic use , High-Density Lipoproteins, Pre-beta/blood , Niacin/therapeutic use , Phytosterols/blood , Xanthophylls/blood , Apolipoprotein A-II/blood , Cross-Over Studies , Dyslipidemias/drug therapy , Dyslipidemias/metabolism , Female , Humans , Hypolipidemic Agents/therapeutic use , Lutein/blood , Male , Middle Aged , Zeaxanthins
14.
Pharmacol Ther ; 138(3): 470-84, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23507039

ABSTRACT

Cardiovascular toxicity remains a major cause of concern during preclinical and clinical development as well as contributing to post-approval withdrawal of medicines. This issue is particularly relevant for anticancer drugs where, the significant improvement in the life expectancies of patients has dramatically extended the use and duration of drug therapies. Nevertheless, cardiotoxicity is also observed with other classes of drugs, including antibiotics, antidepressants, and antipsychotics. This article summarizes the clinical manifestations of drug-induced cardiotoxicity by various cancer chemotherapies and novel drugs for the treatment of other diseases. Furthermore, it presents on overview of biomarker and imaging techniques for the detection of drug-induced cardiotoxicity. Guidelines for the management of patients exposed to drugs with cardiotoxic potential are presented as well as a checklist for collecting information when a safety signal is observed in clinical trials to more effectively assess the risk of cardiotoxicity and manage patient safety.


Subject(s)
Cardiovascular Diseases/chemically induced , Animals , Cardiotoxins/adverse effects , Drug Evaluation, Preclinical , Drug-Related Side Effects and Adverse Reactions , Humans
16.
Int J Cardiovasc Intervent ; 4(4): 165-172, 2001 Dec.
Article in English | MEDLINE | ID: mdl-12036459

ABSTRACT

BACKGROUND: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) inhibit atherosclerosis and reduce both morbidity and mortality in patients with coronary heart disease. No randomised prospective study, however, has investigated the long-term effect of statins on clinical outcomes in patients who have undergone first successful transcatheter therapy. METHODS: The Lescol((R)) Intervention Prevention Study (LIPS) is a double-blind randomized trial designed to compare the effect of fluvastatin (Lescol) with that of placebo on the time which patients with serum cholesterol >/= 3.5 mmol/l and < 7.0 mmol/l (135-270 mg/dl) remain free of major adverse cardiac events (MACE) after successful first transcatheter therapy (TCT). Patients, aged 18-80 years inclusive, will be randomized in a 1 : 1 ratio to receive fluvastatin, 40 mg, or placebo, twice daily for three to five years. The primary endpoint is the survival time during which patients remain MACE free after first TCT. Secondary endpoints are the incidence of MACE, noncardiac death, hospitalization for other atherosclerotic diseases, changes in serum lipid concentrations and anginal status. SUMMARY: LIPS is unique because it is the first study that will investigate whether MACE can be prevented or reduced by fluvastatin in patients who have undergone successful first transcatheter therapy for coronary heart disease.

SELECTION OF CITATIONS
SEARCH DETAIL
...