Efficacy and Safety of Low-Dose Colchicine after Myocardial Infarction.

BACKGROUND: Experimental and clinical evidence supports the role of inflammation in atherosclerosis and its complications. Colchicine is an orally administered, potent antiinflammatory medication that is indicated for the treatment of gout and pericarditis. METHODS: We performed a randomized, double-blind trial involving patients recruited within 30 days after a myocardial infarction. The patients were randomly assigned to receive either low-dose colchicine (0.5 mg once daily) or placebo. The primary efficacy end point was a composite of death from cardiovascular causes, resuscitated cardiac arrest, myocardial infarction, stroke, or urgent hospitalization for angina leading to coronary revascularization. The components of the primary end point and safety were also assessed. RESULTS: A total of 4745 patients were enrolled; 2366 patients were assigned to the colchicine group, and 2379 to the placebo group. Patients were followed for a median of 22.6 months. The primary end point occurred in 5.5% of the patients in the colchicine group, as compared with 7.1% of those in the placebo group (hazard ratio, 0.77; 95% confidence interval [CI], 0.61 to 0.96; P = 0.02). The hazard ratios were 0.84 (95% CI, 0.46 to 1.52) for death from cardiovascular causes, 0.83 (95% CI, 0.25 to 2.73) for resuscitated cardiac arrest, 0.91 (95% CI, 0.68 to 1.21) for myocardial infarction, 0.26 (95% CI, 0.10 to 0.70) for stroke, and 0.50 (95% CI, 0.31 to 0.81) for urgent hospitalization for angina leading to coronary revascularization. Diarrhea was reported in 9.7% of the patients in the colchicine group and in 8.9% of those in the placebo group (P = 0.35). Pneumonia was reported as a serious adverse event in 0.9% of the patients in the colchicine group and in 0.4% of those in the placebo group (P = 0.03). CONCLUSIONS: Among patients with a recent myocardial infarction, colchicine at a dose of 0.5 mg daily led to a significantly lower risk of ischemic cardiovascular events than placebo. (Funded by the Government of Quebec and others; COLCOT ClinicalTrials.gov number, NCT02551094.).

VAP: a versatile aggregate profiler for efficient genome-wide data representation and discovery.

The analysis of genomic data such as ChIP-Seq usually involves representing the signal intensity level over genes or other genetic features. This is often illustrated as a curve (representing the aggregate profile of a group of genes) or as a heatmap (representing individual genes). However, no specific resource dedicated to easily generating such profiles is currently available. We therefore built the versatile aggregate profiler (VAP), designed to be used by experimental and computational biologists to generate profiles of genomic datasets over groups of regions of interest, using either an absolute or a relative method. Graphical representation of the results is automatically generated, and subgrouping can be performed easily, based on the orientation of the flanking annotations. The outputs include statistical measures to facilitate comparisons between groups or datasets. We show that, through its intuitive design and flexibility, VAP can help avoid misinterpretations of genomics data. VAP is highly efficient and designed to run on laptop computers by using a memory footprint control, but can also be easily compiled and run on servers. VAP is accessible at http://lab-jacques.recherche.usherbrooke.ca/vap/.

Effects of reconstituted high-density lipoprotein infusions on coronary atherosclerosis: a randomized controlled trial.

CONTEXT: High-density lipoprotein (HDL) cholesterol is an inverse predictor of coronary atherosclerotic disease. Preliminary data have suggested that HDL infusions can induce atherosclerosis regression. OBJECTIVE: To investigate the effects of reconstituted HDL on plaque burden as assessed by intravascular ultrasound (IVUS). DESIGN AND SETTING: A randomized placebo-controlled trial was conducted at 17 centers in Canada. Intravascular ultrasound was performed to assess coronary atheroma at baseline and 2 to 3 weeks after the last study infusion. PATIENTS: Between July 2005 and October 2006, 183 patients had a baseline IVUS examination and of those, 145 had evaluable serial IVUS examinations after 6 weeks. INTERVENTION: Sixty patients were randomly assigned to receive 4 weekly infusions of placebo (saline), 111 to receive 40 mg/kg of reconstituted HDL (CSL-111); and 12 to receive 80 mg/kg of CSL-111. MAIN OUTCOME MEASURES: The primary efficacy parameter was the percentage change in atheroma volume. Nominal changes in plaque volume and plaque characterization index on IVUS and coronary score on quantitative coronary angiography were also prespecified end points. RESULTS: The higher-dosage CSL-111 treatment group was discontinued early because of liver function test abnormalities. The percentage change in atheroma volume was -3.4% with CSL-111 and -1.6% for placebo (P = .48 between groups, P<.001 vs baseline for CSL-111). The nominal change in plaque volume was -5.3 mm3 with CSL-111 and -2.3 mm3 with placebo (P = .39 between groups, P<.001 vs baseline for CSL-111). The mean changes in plaque characterization index on IVUS (-0.0097 for CSL-111 and 0.0128 with placebo) and mean changes in coronary score (-0.039 mm for CSL-111 and -0.071 mm with placebo) on quantitative coronary angiography were significantly different between groups (P = .01 and P =.03, respectively). Administration of CSL-111 40 mg/kg was associated with mild, self-limiting transaminase elevation but was clinically well tolerated. CONCLUSIONS: Short-term infusions of reconstituted HDL resulted in no significant reductions in percentage change in atheroma volume or nominal change in plaque volume compared with placebo but did result in statistically significant improvement in the plaque characterization index and coronary score on quantitative coronary angiography. Elevation of HDL remains a valid target in vascular disease and further studies of HDL infusions, including trials with clinical end points, appear warranted. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00225719

[Teasing out the various factors associated with the digestive and absorptive phases of intestinal transport]. / Avancées dans la dissection fonctionnelle du transport intestinal des lipides.

The small bowel has traditionally been considered a simple organ for the transport of food-stuffs. Although the function of nutrient delivery is vital, the digestive and absorptive phases of fat were poorly understood until the past two decades. Moreover, the small bowel was not thought to have any modulating transport properties nor a role in the genesis of chronic diseases such as atherosclerosis. Given its enormous capacity to transform nutrients and to synthesize atherogenic proteins and gastro-intestinal peptides, the intestinal epithelium plays a key role in a number of metabolic pathways. The aim of the brief review is to provide an update on recent advances in our understanding of the absorption of dietary lipids with emphasis on the role and contribution of key proteins to malabsorptive syndromes as well as hyperlipidemic syndromes and eventually to atherosclerosis.

Beneficial Effects of Reconstituted High-Density Lipoprotein (rHDL) on Circulating CD34+ Cells in Patients after an Acute Coronary Syndrome.

BACKGROUND: High-density lipoproteins (HDL) favorably affect endothelial progenitor cells (EPC). Circulating progenitor cell level and function are impaired in patients with acute coronary syndrome (ACS). This study investigates the short-term effects of reconstituted HDL (rHDL) on circulating progenitor cells in patients with ACS. METHODS AND FINDINGS: The study population consisted of 33 patients with recent ACS: 20 patients from the ERASE trial (randomized to receive 4 weekly intravenous infusions of CSL-111 40 mg/kg or placebo) and 13 additional patients recruited as controls using the same enrolment criteria. Blood was collected from 16 rHDL (CSL-111)-treated patients and 17 controls at baseline and at 6-7 weeks (i.e. 2-3 weeks after the fourth infusion of CSL-111 in ERASE). CD34+ and CD34+/kinase insert domain receptor (KDR+) progenitor cell counts were analyzed by flow cytometry. We found preserved CD34+ cell counts in CSL-111-treated subjects at follow-up (change of 1.6%), while the number of CD34+ cells was reduced (-32.9%) in controls (p = 0.017 between groups). The level of circulating SDF-1 (stromal cell-derived factor-1), a chemokine involved in progenitor cell recruitment, increased significantly (change of 21.5%) in controls, while it remained unchanged in CSL-111-treated patients (p = 0.031 between groups). In vitro exposure to CSL-111 of early EPC isolated from healthy volunteers significantly increased CD34+ cells, reduced early EPC apoptosis and enhanced their migration capacity towards SDF-1. CONCLUSIONS: The relative increase in circulating CD34+ cells and the low SDF-1 levels observed following rHDL infusions in ACS patients point towards a role of rHDL in cardiovascular repair mechanisms.

Effect of atherosclerotic regression on total luminal size of coronary arteries as determined by intravascular ultrasound.

We assessed vascular changes during atherosclerosis regression. Compensatory enlargement of coronary arteries accommodates plaque burden during atherosclerosis development. Lipid-lowering therapy has altered the natural history of coronary atherosclerosis, but the arterial changes that occur during disease regression need to be clarified. Intravascular ultrasound was performed at baseline and after approximately 18 months in 432 patients with coronary disease. Mean plaque, lumen, and total vessel area were computed in a 30-mm coronary segment of interest. Mean low-density lipoprotein cholesterol level was 2.4 mmol/L, and 88% of patients received statins. Overall, changes in plaque and total vessel areas were highly correlated (r = 0.82, p <0.0001). Among the 227 patients with plaque regression, the plaque area decrease was -0.58 +/- 0.54 mm(2), and changes in total vessel and lumen areas were -1.02 +/- 1.10 and -0.44 +/- 0.86 mm(2), respectively. The decrease in plaque area correlated better with the change in total vessel area (r = 0.64, p <0.0001) than with the change in lumen area (r = 0.20, p = 0.003). The relation between plaque regression and decrease in total vessel area was significantly better (p = 0.019) for patients with a >40% atheroma area (r = 0.72; p <0.0001) than for those with

Statin therapy in Canadian patients with hypercholesterolemia: the Canadian Lipid Study -- Observational (CALIPSO).

BACKGROUND: Although statins are widely used to reduce low density lipoprotein cholesterol (LDL-C), there is little information about patient profiles, treatment patterns and goal achievement among statin-treated patients in Canada. OBJECTIVES: To assess the profile of statin-treated patients and to determine whether they are achieving recommended targets for LDL-C. METHODS: The Canadian Lipid Study -- Observational (CALIPSO) was a cross-sectional study involving Canadian physicians who were among the top statin prescribers. Each physician enrolled up to 15 patients who were at least 18 years of age with a diagnosis of hyper-cholesterolemia and who had been using a statin for at least eight weeks. Sociodemographics, coronary artery disease (CAD) risk factors, pretreatment and current lipid levels, and history of lipid-lowering therapy were reported for 3721 patients. RESULTS: Sixty-eight per cent of statin-treated patients were at high CAD risk according to the 2003 Canadian guidelines, 46.4% had established cardiovascular disease, 33.9% had diabetes and 59.5% had hypertension. Average LDL-C reductions of 32% (37% for high-risk patients) were initially required to reach goal. At the study visit, patients had been treated for an average of 4.3 years and 24.2% were using a high statin dose. Despite statin therapy, 27.2% of all patients and 36.4% of those at high CAD risk had not achieved LDL-C targets. For 67.4% of these patients, the current therapy was not modified at the study visit. CONCLUSIONS: Despite effective therapies, many treated patients are not achieving recommended LDL-C targets. Strategies should be implemented to promote achievement of lipid treatment goals for high-risk patients, thereby reducing the risk of cardiovascular events and their associated clinical and economic burdens.

Vascular protectants for the treatment of atherosclerosis.

AGI-1067, the monosuccinic acid ester of probucol, is a phenolic antioxidant member of a novel class of agents termed vascular protectants. It has strong antioxidant properties, equipotent to those of probucol, and anti-inflammatory properties. It inhibits gene expression of vascular cell adhesion molecule-1 and monocyte chemotactic protein-1 and has been effective at preventing atherosclerosis in all tested animal models. It also improved luminal dimensions of reference segments in the percutaneous coronary intervention (PCI) vessels in the CART-1 clinical trial, which suggests a direct anti-atherosclerosis effect. Two important trials that test the antioxidant/anti-inflammatory hypothesis are ongoing with AGI-1067: the Canadian Atherosclerosis and Restenosis Trial, which assesses its value for the reduction of both atherosclerosis progression in non-PCI vessels and post-PCI restenosis, and the Aggressive Reduction of Inflammation Stops Events trial, which is evaluating the effects of AGI-1067 on hard cardiovascular outcomes.

Ezetimibe and cholesterol absorption.

Cholesterol, an important biological lipid and excessive dietary intake, is associated with hypercholesterolemia, a prevalent cardiovascular risk factor. Because cholesterol is essentially a water insoluble molecule, its transport within and absorption from the aqueous medium of the intestine is rather complex. This takes place in a series of orderly and interrelated steps, including emulsification, hydrolysis by specific pancreatic esterases, micellar transport, mucosal absorption, resynthesis in enterocytes and assembly with apolipoproteins to form chylomicrons. Many of these processes are not well characterized at the molecular level. Besides being generally inefficient, cholesterol absorption is highly variable with a between-subject variability that depends in part on genetic factors and an intraindividual variability, which may be modulated by physiological and dietary conditions. All of the sequential steps in intestinal cholesterol absorption can be interfered with by dietary components or drugs and therefore are potential therapeutic targets for rendering cholesterol absorption even more inefficient in an attempt to lower cholesterol levels.

Treatment with 5-lipoxygenase inhibitor VIA-2291 (Atreleuton) in patients with recent acute coronary syndrome.

BACKGROUND: Production of leukotrienes by 5-lipoxygenase (5-LO) has been linked to unstable atherosclerotic plaques and cardiovascular events. VIA-2291 is a potent 5-LO inhibitor. METHODS AND RESULTS: In a double-blinded study, 191 patients were randomly assigned 3 weeks after an acute coronary syndrome to receive 25, 50, or 100 mg VIA-2291 or placebo daily for 12 weeks. The primary study end point, whole blood stimulated leukotriene LTB4 at trough drug level, was reduced in all VIA-2291 groups (P<0.0001) in a dose-dependent fashion, with approximately 80% inhibition in >90% of patients in the 100-mg group. A significant reduction of urine leukotriene LTE4 was obtained in all dose groups. No serious adverse events were considered related to study drug. A subset of 93 patients who had undergone a 64-slice coronary CT examination at baseline continued on study medication for a total of 24 weeks and underwent a repeat scan. Five of these patients withdrew or were noncompliant and 28 had nonevaluable scans. Among the 60 remaining patients, new coronary plaques were observed in 5 of 18 (27.8%) placebo-treated patients and in 2 of 42 (4.8%) VIA-2291-treated patients (P=0.01). A reduction in noncalcified plaque volume at 24 weeks versus placebo was observed in VIA-2291-treated groups in the 34 of these 60 patients in whom this end point was analyzable (P<0.01). CONCLUSIONS: VIA-2291 reduces leukotriene production at 12 weeks after an acute coronary syndrome. Preliminary data from the CT substudy suggest that such a reduction in leukotriene production may influence atherosclerosis; however, this requires confirmation in a larger study. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00358826.

Limitations of statin monotherapy for the treatment of dyslipidemia: a projection based on the Canadian lipid study--observational.

OBJECTIVE: Several randomized controlled trials indicate that a low density lipoprotein cholesterol (LDL-C) target <2.0 mmol/L is appropriate for individuals at high risk of coronary artery disease (CAD). Recently released Canadian lipid management guidelines (2006) have incorporated this evidence into their recommendations. A cross-sectional study of patients treated with statins for at least 8 weeks (CALIPSO) was used as a basis to project the ability of statin monotherapy in getting high CAD-risk patients to an LDL-C level <2.0 mmol/L. RESEARCH DESIGN AND METHODS: The analysis was restricted to CALIPSO patients on statin monotherapy who were at high CAD-risk (including patients with established CAD). Assuming all patients could have their statin titrated up to the maximum dose, the proportion of patients that would reach an LDL-C level of <2.0 mmol/L was projected. To do this, the additional LDL-C reduction patients would achieve with maximal titration of their statin was estimated based on a meta-analysis of clinical trials evaluating LDL-C responses to various statin regimens, and applied to patients' current LDL-C level. RESULTS: A total of 1795 high CAD-risk patients treated with statin monotherapy were included in the analysis, of whom 69.8% had an LDL-C > or =2.0 mmol/L. Depending on the statin that was used, it was projected that between 28.2% and 62.7% of high CAD-risk patients would not attain an LDL-C of <2.0 mmol/L following statin titration to maximum dose. CONCLUSIONS: Although the accuracy of our projections may be limited by the application of clinical trials data to an external sample of patients, our results suggest that for 38% of patients at high CAD-risk, titration of statin monotherapy will not be sufficient to achieve an LDL-C target of <2.0 mmol/L. For these patients, additional treatment approaches may be needed to further reduce the risk of coronary events.

Intestinal cholesterol transport proteins: an update and beyond.

PURPOSE OF REVIEW: Various studies have delineated the causal role of dietary cholesterol in atherogenesis. Strategies have thus been developed to minimize cholesterol absorption, and cholesterol transport proteins found at the apical membrane of enterocytes have been extensively investigated. This review focuses on recent progress related to various brush-border proteins that are potentially involved in alimentary cholesterol transport. RECENT FINDINGS: Molecular mechanisms responsible for dietary cholesterol and plant sterol uptake have not been completely defined. Growing evidence, however, supports the concept that several proteins are involved in mediating intestinal cholesterol transport, including SR-BI, NPC1L1, CD36, aminopeptidase N, P-glycoprotein, and the caveolin-1/annexin-2 heterocomplex. Other ABC family members (ABCA1 and ABCG5/ABCG8) act as efflux pumps favoring cholesterol export out of absorptive cells into the lumen or basolateral compartment. Several of these cholesterol carriers influence intracellular cholesterol homeostasis and are controlled by transcription factors, including RXR, LXR, SREBP-2 and PPARalpha. The lack of responsiveness of NPC1L1-deficient mice to ezetimibe suggests that NPC1L1 is likely to be the principal target of this cholesterol-lowering drug. SUMMARY: The understanding of the role, genetic regulation and coordinated function of proteins mediating intestinal cholesterol transport may lead to novel ways of treating cardiovascular disease.

Pharmacologic prevention of both restenosis and atherosclerosis progression: AGI-1067, probucol, statins, folic acid and other therapies.

PURPOSE OF REVIEW: In this article, the authors intend to provide an update on clinical trials of pharmacologic prevention of restenosis after percutaneous coronary interventions, placed in the perspective of the use of orally administered therapy for the prevention of atherosclerosis progression and clinical events. RECENT FINDINGS: AGI-1067, the mono-succinic acid ester of probucol, is a phenolic antioxidant member of a novel class of agents termed v-protectants. It has strong antioxidant properties equipotent to those of probucol and antiinflammatory properties. It inhibits gene expression of VCAM-1 and MCP-1 and has been effective at preventing atherosclerosis in all tested animal models including the non-human primate. In the Canadian Antioxidant Restenosis Trial (CART) 1, AGI-1067 and probucol improved lumen dimensions at the site of percutaneous coronary intervention. AGI-1067 also improved luminal dimensions of non-intervened coronary reference segments in the Canadian Antioxidant Restenosis Trial, which suggests a direct antiatherosclerosis effect. Probucol reduced post-percutaneous coronary intervention restenosis and progression of carotid atherosclerosis in other clinical trials. Although statins reduce atherosclerotic events, they do not appear to have a significant effect on restenosis. The failure of folate therapy to protect against restenosis in the Folate After Coronary Intervention Trial (FACIT) occurred despite significant reductions in homocysteine levels. SUMMARY: Prevention of both post-percutaneous coronary intervention restenosis and atherosclerosis progression with a pharmacologic agent such as AGI-1067 may be an attractive treatment paradigm. Two important trials that test the antioxidant/antiinflammatory hypothesis are ongoing with AGI-1067: the Canadian Atherosclerosis and Restenosis Trial 2, which assesses its value for the reduction of both atherosclerosis progression and post-percutaneous coronary interventions restenosis, and the Aggressive Reduction of Inflammation Stops Events (ARISE) trial which is evaluating its effects on cardiovascular events.