Changes in lipoproteins associated with lipid-lowering and antiplatelet strategies in patients with acute myocardial infarction.

BACKGROUND: Despite lipid-lowering and antiplatelet therapy, the pattern of residual lipoproteins seems relevant to long-term cardiovascular outcomes. This study aims to evaluate the effects of combined therapies, commonly used in subjects with acute myocardial infarction, in the quality of low-density lipoprotein (LDL) particles. METHODS: Prospective, open-label trial, included patients with acute myocardial infarction. Patients were randomized to antiplatelet treatment (ticagrelor or clopidogrel) and subsequently to lipid-lowering therapy (rosuvastatin or simvastatin/ezetimibe) and were followed up for six months. Nonlinear optical properties of LDL samples were examined by Gaussian laser beam (Z-scan) to verify the oxidative state of these lipoproteins, small angle X-ray scattering (SAXS) to analyze structural changes on these particles, dynamic light scattering (DLS) to estimate the particle size distribution, ultra violet (UV)-visible spectroscopy to evaluate the absorbance at wavelength 484 nm (typical from carotenoids), and polyacrylamide gel electrophoresis (Lipoprint) to analyze the LDL subfractions. RESULTS: Simvastatin/ezetimibe with either clopidogrel or ticagrelor was associated with less oxidized LDL, and simvastatin/ezetimibe with ticagrelor to lower cholesterol content in the atherogenic subfractions of LDL, while rosuvastatin with ticagrelor was the only combination associated with increase in LDL size. CONCLUSIONS: The quality of LDL particles was influenced by the antiplatelet/lipid-lowering strategy, with ticagrelor being associated with the best performance with both lipid-lowering therapies. Trial registration: NCT02428374.

Role of Inflammation in Cardiac Remodeling After Acute Myocardial Infarction.

Atherosclerosis is defined as an inflammatory disease. Low-grade inflammation is present in all phases of the cardiovascular continuum, since the establishment of cardiovascular risk factors and ischemic heart disease until cardiovascular events, such as myocardial infarction, heart failure and death. Not all inflammatory pathways are linked to cardiovascular outcomes, and thus, not all anti-inflammatory approaches decrease cardiovascular events. The most common cause of ventricular remodeling and heart failure is ischemic heart disease. Biomarkers such as high-sensitivity C-reactive protein can identify individuals at risk of major cardiovascular complications, but this biomarker has no causal effect on cardiovascular disease. On the other hand, interleukin 6 appears to be causally associated with cardiovascular disease. CANTOS was the first proof of concept study showing that anti-inflammatory therapy reduces major cardiovascular outcomes. Based on many anti-inflammatory trials, only therapies acting on the NLRP3 inflammasome, or interleukin 1beta, showed benefits on cardiovascular disease. Ventricular remodeling, particularly after myocardial infarction seems also influenced by the intensity of inflammatory responses, suggesting that anti-inflammatory therapies may reduce the residual cardiovascular risk. Inflammasome (NLRP3) activation, subtypes of lymphocytes, interleukin 6, and some inflammatory biomarkers, are associated with larger infarct size and impaired ventricular function after myocardial infarction. Cardiovascular risk factors commonly present in patients with myocardial infarction, and advanced age are associated with higher inflammatory activity.

Atherosclerosis severity in patients with familial hypercholesterolemia: The role of T and B lymphocytes.

Background and aims: Familial hypercholesterolemia (FH) is characterized by lifelong exposure to high LDL-c concentrations and premature atherosclerotic cardiovascular disease; nevertheless, disease severity can be heterogeneous.We aimed at evaluating if the immune-inflammatory system could modulate atherosclerosis burden in FH. Methods: From a cohort of subjects with confirmed FH (Dutch Lipid Clinic Network and genotype), 92 patients receiving high-intensity lipid-lowering therapy (statin ± ezetimibe) were included. The extension and severity of coronary atherosclerosis was assessed by standardized reporting systems (CAD-RADS) for coronary computed tomography angiography (CCTA) and coronary artery calcium (CAC) scores. Lipids, apolipoproteins, anti-oxLDL and anti-apolipoprotein B-D peptide (anti-ApoB-D) autoantibodies (IgM and IgG), lymphocytes subtypes, platelet, monocyte and endothelial microparticles (MP), IgM levels (circulating or produced by B1 cells) and cytokines in the supernatant of cultured cells were determined. Multiple linear regression models evaluated associations of these biomarkers with CAC and CAD-RADS scores. Results: In univariate analysis CAC correlated with age, systolic blood pressure, TCD4+ cells, and titers of IgM anti-ApoB-D. In multiple linear regression [ANOVA F = 2.976; p = 0.024; R2 = 0.082), CD4+T lymphocytes (B = 35.289; beta = 0.277; p = 0.010; 95%CI for B 8.727 to 61.851), was independently associated with CAC. CAD-RADS correlated with age, systolic blood pressure, titers of IgM anti-ApoB-D, and endothelial MP in univariate analysis. In multiple linear regression, [ANOVA F = 2.790; p = 0.032; R2 = 0.119), only age (B = 0.027; beta = 0.234; p = 0.049; 95% CI for B 0.000 to 0.053) was independent predictor. Conclusions: In subjects with FH, under high-intensity lipid-lowering therapy, age and CD4+T cells were associated to atherosclerosis burden.

Main differences between two highly effective lipid-lowering therapies in subclasses of lipoproteins in patients with acute myocardial infarction.

BACKGROUND: Large observational studies have shown that small, dense LDL subfractions are related to atherosclerotic cardiovascular disease. This study assessed the effects of two highly effective lipid-lowering therapies in the atherogenic subclasses of lipoproteins in subjects with ST-segment elevation myocardial infarction (STEMI). METHODS: Patients of both sexes admitted with their first myocardial infarction and submitted to pharmacoinvasive strategy (N = 101) were included and randomized using a central computerized system to receive a daily dose of simvastatin 40 mg plus ezetimibe 10 mg or rosuvastatin 20 mg for 30 days. Intermediate-density lipoprotein (IDL) and low-density lipoprotein (LDL) subfractions were analysed by polyacrylamide gel electrophoresis (Lipoprint System) on the first (D1) and 30th days (D30) of lipid-lowering therapy. Changes in LDL and IDL subfractions between D1 and D30 were compared between the lipid-lowering therapies (Mann-Whitney U test). RESULTS: The classic lipid profile was similar in both therapy arms at D1 and D30. At D30, the achievement of lipid goals was comparable between lipid-lowering therapies. Cholesterol content in atherogenic subclasses of LDL (p = 0.043) and IDL (p = 0.047) decreased more efficiently with simvastatin plus ezetimibe than with rosuvastatin. CONCLUSIONS: Lipid-lowering therapy with simvastatin plus ezetimibe was associated with a better pattern of lipoprotein subfractions than rosuvastatin monotherapy. This finding was noted despite similar effects in the classic lipid profile and may contribute to residual cardiovascular risk. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02428374, registered on 28/09/2014.

Role of B lymphocytes in the infarcted mass in patients with acute myocardial infarction

Introduction: Almost 20% of patients with acute myocardial infarction (MI) develop heart failure, even when early reperfused [1]. Left ventricular remodeling seems related to the size of myocardial infarction and timely reperfusion, as well as to the inflammatory responses and residual ischemia [2]. Experimental studies suggested that B lymphocytes may influence the myocardial infarcted mass [3], although there are few data about the role of these cells in humans. Furthermore, a possible atheroprotective role for B1 lymphocytes has been proposed based on the production of interleukin 10 (IL-10) and natural antibodies, which may switch the proinflammatory response to more appropriate healing, promoting cell recovery and the clearance of apoptotic cellular debris [4]. On the other hand, classic B lymphocytes or B2 cells are linked to progression of atherosclerosis, possibly by their interaction with CD4+ T lymphocytes [4]. In 2011, Griffin and colleagues proposed CD19+CD20+CD43+CD70- lymphocyte cells as the human B1 phenotype, and these cells spontaneously produced IgM and IL-10 [5]. However, according to the presence or absence of the CD11b on the surface of these cells, the capacity of IgM production and activation Stem cells in blood marrow differentiate in T or B lymphocyte, according to the presence of CD3 or CD19, respectively. Lymphocyte final maturation takes place in thymus for T cells; or in spleen and lymphatic tissue for classic B cells. B1 lymphocytes are well described in experimental studies. These cells are notorious for their capacity of spontaneous production of IgM and according to the presence of the CD11b, two distinct subtypes are recognized: CD11b- B1 lymphocytes, producing IgM, and CD11b+ B1 lymphocytes, related to the expansion of CD4+ T lymphocytes.

Role of B lymphocytes in the infarcted mass in patients with acute myocardial infarction.

Despite early reperfusion, patients with ST segment elevation myocardial infarction (STEMI) may present large myocardial necrosis and significant impairment of ventricular function. The present study aimed to evaluate the role of subtypes of B lymphocytes and related cytokines in the infarcted mass and left ventricular ejection fraction obtained by cardiac magnetic resonance imaging performed after 30 days of STEMI. This prospective study included 120 subjects with STEMI submitted to pharmacoinvasive strategy. Blood samples were collected in subjects in the first (D1) and 30th (D30) days post STEMI. The amount of CD11b+ B1 lymphocytes (cells/ml) at D1 were related to the infarcted mass (rho = 0.43; P=0.033), measured by cardiac MRI at D30. These B1 cells were associated with CD4+ T lymphocytes at D1 and D30, while B2 classic lymphocytes at day 30 were related to left ventricular ejection fraction (LVEF). Higher titers of circulating IL-4 and IL-10 were observed at D30 versus D1 (P=0.013 and P<0.001, respectively). Titers of IL-6 at D1 were associated with infarcted mass (rho = 0.41, P<0.001) and inversely related to LVEF (rho = -0.38, P<0.001). After multiple linear regression analysis, high-sensitivity troponin T and IL-6 collected at day 1 were independent predictors of infarcted mass and, at day 30, only HDL-C. Regarding LVEF, high-sensitivity troponin T and high-sensitivity C-reactive protein were independent predictors at day 1, and B2 classic lymphocytes, at day 30. In subjects with STEMI, despite early reperfusion, the amount of infarcted mass and ventricular performance were related to inflammatory responses triggered by circulating B lymphocytes.

Reducing the Clinical and Public Health Burden of Familial Hypercholesterolemia: A Global Call to Action.

Importance: Familial hypercholesterolemia (FH) is an underdiagnosed and undertreated genetic disorder that leads to premature morbidity and mortality due to atherosclerotic cardiovascular disease. Familial hypercholesterolemia affects 1 in 200 to 250 people around the world of every race and ethnicity. The lack of general awareness of FH among the public and medical community has resulted in only 10% of the FH population being diagnosed and adequately treated. The World Health Organization recognized FH as a public health priority in 1998 during a consultation meeting in Geneva, Switzerland. The World Health Organization report highlighted 11 recommendations to address FH worldwide, from diagnosis and treatment to family screening and education. Research since the 1998 report has increased understanding and awareness of FH, particularly in specialty areas, such as cardiology and lipidology. However, in the past 20 years, there has been little progress in implementing the 11 recommendations to prevent premature atherosclerotic cardiovascular disease in an entire generation of families with FH. Observations: In 2018, the Familial Hypercholesterolemia Foundation and the World Heart Federation convened the international FH community to update the 11 recommendations. Two meetings were held: one at the 2018 FH Foundation Global Summit and the other during the 2018 World Congress of Cardiology and Cardiovascular Health. Each meeting served as a platform for the FH community to examine the original recommendations, assess the gaps, and provide commentary on the revised recommendations. The Global Call to Action on Familial Hypercholesterolemia thus represents individuals with FH, advocacy leaders, scientific experts, policy makers, and the original authors of the 1998 World Health Organization report. Attendees from 40 countries brought perspectives on FH from low-, middle-, and high-income regions. Tables listing country-specific government support for FH care, existing country-specific and international FH scientific statements and guidelines, country-specific and international FH registries, and known FH advocacy organizations around the world were created. Conclusions and Relevance: By adopting the 9 updated public policy recommendations created for this document, covering awareness; advocacy; screening, testing, and diagnosis; treatment; family-based care; registries; research; and cost and value, individual countries have the opportunity to prevent atherosclerotic heart disease in their citizens carrying a gene associated with FH and, likely, all those with severe hypercholesterolemia as well.

Monocyte subtypes and the CCR2 chemokine receptor in cardiovascular disease.

Monocytes circulate in the blood and migrate to inflammatory tissues, but their functions can be either detrimental or beneficial, depending on their phenotypes. In humans, classical monocytes are inflammatory cluster of differentiation (CD)14++CD16-CCR2++ cells originated from the bone marrow or spleen reservoirs and comprise ≥92% of monocytes. Intermediate monocytes (CD14++CD16+CCR2+) are involved in the production of anti-inflammatory cytokines [such as interleukin (IL)-10], reactive oxygen species (ROS), and proinflammatory mediators [such as tumor necrosis factor-α (TNF-α) and IL-1ß). Nonclassical monocytes (CD14+CD16++CCR2-) are patrolling cells involved in tissue repair and debris removal from the vasculature. Many studies in both humans and animals have shown the importance of monocyte chemoattractant protein-1 (MCP-1) and its receptor [chemokine receptor of MCP-1 (CCR2)] in pathologies, such as atherosclerosis and myocardial infarction (MI). This review presents the importance of these monocyte subsets in cardiovascular diseases (CVDs), and sheds light on new strategies for the blocking of the MCP-1/CCR2 axis as a therapeutic goal for treating vascular disorders.

Statin-associated muscle symptoms: position paper from the Luso-Latin American Consortium.

In the last two decades, statin therapy has proved to be the most potent isolated therapy for attenuation of cardiovascular risk. Its frequent use has been seen as one of the most important elements for the reduction of cardiovascular mortality in developed countries. However, the recurrent incidence of muscle symptoms in statin users raised the possibility of causal association, leading to a disease entity known as statin associated muscle symptoms (SAMS). Mechanistic studies and clinical trials, specifically designed for the study of SAMS have allowed a deeper understanding of the natural history and accurate incidence. This set of information becomes essential to avoid an unnecessary risk of severe forms of SAMS. At the same time, this concrete understanding of SAMS prevents overdiagnosis and an inadequate suspension of one of the most powerful prevention strategies of our times. In this context, the Luso-Latin American Consortium gathered all available information on the subject and presents them in detail in this document as the basis for the identification and management of SAMS.

Challenges Facing the Use of Endothelial Progenitor Cells in Stem Cell Therapies.

The paper summarizes the difficulties to study the rare population of endothelial progenitor cells in clinical trials, based on the experience of our group in many publications in this area.

Antihypertensive therapy increases natural immunity response in hypertensive patients.

AIMS: The aim of this work was to evaluate the effects of treatment of hypertension on the autoantibodies to apolipoprotein B-derived peptides (anti-ApoB-D peptide Abs) response, inflammation markers and vascular function. MAIN METHODS: Eighty-eight patients with hypertension (stage 1 or 2) were recruited and advised to receive perindopril (4mg), hydrochlorothiazide (25mg), or indapamide (1.5mg) for 12weeks in a blinded fashion. Office and 24-h ambulatory blood pressure monitoring (24h ABPM), flow-mediated dilatation (FMD), nitrate-induced dilatation (NID), titers of IgG and IgM anti-ApoB-D peptide Abs, hsCRP, and interleukins (IL-8 and IL-10) were evaluated at baseline and 12weeks after therapies. KEY FINDINGS: All treatments reduced office BP, and improved FMD (P<0.05 vs. baseline). The NID was improved only in the perindopril arm (P<0.05 vs. baseline). The 24h-ABPM was reduced with perindopril and hydrochlorothiazide therapies (P<0.05 vs. baseline), but not with indapamide, and this effect was followed by increase in titers of IgM Anti-ApoB-D peptide Abs (P<0.05 vs. baseline), without modifications in titers IgG Anti-ApoB-D peptide Abs and interleukins. Multivariable regression analysis has shown that change in the titers of IgM anti-ApoB-D peptide was associated with the changes in FMD (ß -0.347; P<0.05). SIGNIFICANCE: These findings shed light to a possible modulator effect of the antihypertensive therapy on the natural immunity responses and vascular function.

Additive effects of plant sterols supplementation in addition to different lipid-lowering regimens.

OBJECTIVE: Plant sterol (PS) supplementation has been widely used alone or combined with lipid-lowering therapies (LLTs) to reduce low-density lipoprotein (LDL) cholesterol. The effects of PS added to high-intensity LLT are less reported, especially regarding the effects on cholesterol synthesis and absorption. METHODS: A prospective, randomized, open-label study, with parallel arms and blinded end points was designed to evaluate the effects of addition of PS to LLT on LDL cholesterol, markers of cholesterol synthesis, and absorption. Eighty-six patients of both genders were submitted to a 4-wk run-in period with atorvastatin 10 mg (baseline). Following, subjects received atorvastatin 40 mg, ezetimibe 10 mg, or combination of both drugs for another 4-wk period (phase I). In phase II, capsules containing 2.0 g of PSs were added to previous assigned treatments for 4 wk. Lipids, apolipoproteins, plasma campesterol, ß-sitosterol, and desmosterol levels were assayed at all time points. Within and between-group analyses were performed. RESULTS: Compared with baseline, atorvastatin 40 mg reduced total and LDL cholesterol (3% and 22%, respectively, P < .05), increased ß-sitosterol, campesterol/cholesterol, and ß-sitosterol/cholesterol ratios (39%, 47%, and 32%, respectively, P < .05); ezetimibe 10 mg reduced campesterol and campesterol/cholesterol ratio (67% and 70%, respectively, P < .05), and the combined therapy decreased total and LDL cholesterol (22% and 38%, respectively, P < .05), campesterol, ß-sitosterol, and campesterol/cholesterol ratio (54%, 40%, and 27%, P < .05). Addition of PS further reduced total and LDL cholesterol by ∼ 7.7 and 6.5%, respectively, in the atorvastatin therapy group and 5.0 and 4.0% in the combined therapy group (P < .05, for all), with no further effects in absorption or synthesis markers. CONCLUSIONS: PS added to LLT can further improve lipid profile, without additional effects on intestinal sterol absorption or synthesis.

Obesity modulates the immune response to oxidized LDL in hypertensive patients.

Obesity and hypertension have been recognized as inflammatory diseases capable of activating the immune system, thus contributing to an increased cardiovascular risk. However, the link between adaptive immunity, obesity, and hypertension is poorly understood. We investigated the relationship of the body mass index (BMI) on the inflammatory, vascular, and immune responses in patients with hypertension naïve of anti-hypertensive treatment. Hypertensive patients (N = 88) were divided into three groups: normal weight (NW), overweight (OW), and obese (OB) subjects. Anti-oxidized LDL autoantibodies (anti-oxLDL Abs), anti-ApoB-D peptide (anti-ApoB-D) Abs, interleukin (IL)-8 and IL-10, flow-mediated dilation (FMD) of the brachial artery, and 24-h ambulatory blood pressure monitoring (ABPM) were assessed. OB patients presented lower levels of anti-oxLDL Abs and IL-10, higher levels of IL-8, and impaired FMD, when compared to NW and OW (P < 0.05), without differences between groups regarding anti-ApoB-D Abs. After adjusting for age, systolic and diastolic blood pressure, anti-oxLDL Abs were inversely correlated with BMI and waist circumference (r = -0.24, P = 0.02 and r = -0.25, P = 0.02, respectively), whereas ApoB-D correlated with 24-h ABPM (r = 0.22, P = 0.05 for systolic, and r = 0.29, P = 0.01 for diastolic blood pressure). Regression analyses showed inverse associations of anti-oxLDL Abs with BMI (ß = -0.05, P = 0.01) and waist circumference (ß = -0.01, P = 0.02); anti-ApoB-D Abs were associated with systolic and diastolic 24-h ABPM (ß = 0.96, P = 0.04; ß = 1.02, P = 0.005, for systolic and diastolic 24-h ABPM, respectively). Among hypertensive patients, obesity modulates the immune and inflammatory milieu, determining an unfavorable balance of cytokines and reduction in titers of anti-oxLDL Abs. Twenty-four hour ABPM is associated with titers of anti-ApoB-D Abs.

Effects of ezetimibe on markers of synthesis and absorption of cholesterol in high-risk patients with elevated C-reactive protein.

AIMS: High-risk subjects with elevated C-reactive protein (CRP) are at high risk for cardiovascular events and frequently require potent statins or combined lipid-lowering therapy to achieve lipid targets and decrease inflammation. Our study aimed at evaluating the effects of three lipid-modifying therapies on LDL-cholesterol, CRP levels and markers of cholesterol absorption and synthesis. MAIN METHODS: A prospective intervention study was performed in high cardiovascular risk individuals receiving atorvastatin 10mg daily for four weeks. Those with CRP≥2.0mg/L were randomized to another four-week treatment period with atorvastatin 40mg, ezetimibe 10mg or the combination of atorvastatin 40mg / ezetimibe 10mg. Lipids, markers of cholesterol absorption (campesterol and ß-sitosterol), and synthesis (desmosterol), as well as CRP were quantified at baseline and end of study. KEY FINDINGS: One hundred and twenty two individuals were included. Atorvastatin alone or combined with ezetimibe reduced both LDL-cholesterol and CRP (P<0.002 vs. baseline; Wilcoxon); ezetimibe did not modify CRP. Ezetimibe-based therapies reduced absorption markers and their ratios to cholesterol (P<0.0001 vs. baseline, for all; Wilcoxon), whereas atorvastatin alone increased campesterol/cholesterol and ß-sitosterol/cholesterol ratios (P<0.05 vs. baseline; Wilcoxon). In addition, ezetimibe also increased desmosterol and desmosterol/cholesterol ratio (P<0.0001 vs. baseline; Wilcoxon). SIGNIFICANCE: These results contribute to understanding the link between cellular cholesterol homeostasis, inflammation and lipid-modifying therapies. Our findings highlight the broader benefit of combined therapy with a potent statin and ezetimibe decreasing inflammation, and preventing increase in cholesterol biosynthesis, an effect not observed with ezetimibe alone.

Adaptive immunity is related to coronary artery disease severity after acute coronary syndrome in subjects with metabolic syndrome.

Metabolic syndrome (MetS) is an inflammatory state associated with high coronary disease risk. Inflammation and adaptive immunity modulate atherosclerosis and plaque instability. We examined early changes in anti-oxidized low-density lipoprotein (LDL) (anti-oxLDL) autoantibodies (Abs) in patients with MetS after an acute coronary syndrome (ACS). Patients of both genders (n=116) with MetS were prospectively included after an acute myocardial infarction (MI) or hospitalization due to unstable angina. Anti-oxLDL Abs (IgG class) were assayed at baseline, three and six weeks after ACS. The severity of coronary disease was evaluated by the Gensini score. We observed a decrease in anti-oxLDL Abs titers (p<0.002 vs. baseline), mainly in males (p=0.01), in those under 65 y (p=0.03), and in subjects with Gensini score above median (p=0.04). In conclusion, early decrease in circulating anti-oxLDL Abs is associated with coronary disease severity among subjects with MetS.

Endothelial progenitor cell mobilization and platelet microparticle release are influenced by clopidogrel plasma levels in stable coronary artery disease.

BACKGROUND: Increased numbers of endothelial (EMP) and platelet (PMP) microparticles have been related to cardiovascular risk factors and coronary artery disease. Little is known about the early effects of statins and clopidogrel on these new biomarkers of vascular homeostasis. The aim of the present study was to evaluate pharmacokinetic interactions between atorvastatin and clopidogrel and their effects, alone or combined, on EMP, PMP, and endothelial progenitor cells (EPC). METHODS AND RESULTS: A prospective open-label study enrolled subjects with stable coronary disease (n=26). Drugs were given daily for 3 weeks (atorvastatin 80 mg, visits 1-3; clopidogrel 75 mg, visits 2-4). Counts of EPC (CD34+/CD133+/KDR+), EMP (CD51+) and PMP (CD42+/CD31+), and pharmacokinetic parameters over 24h were assessed at each visit. Atorvastatin plasma concentrations were increased by concomitant therapy with clopidogrel (maximum serum concentration [C(max)], P=0.002; area under the clopidogrel or atorvastatin plasma concentration vs. time curve from 0 to the last detectable concentration [AUC(last)], P=0.03). After atorvastatin withdrawal there was an increase in clopidogrel plasma concentrations (C(max), P=0.009; AUC(last), P=0.039). PMP were inversely correlated with clopidogrel C(max) on visit 3 (rho=-0.57, P=0.006) and on visit 4 (rho=-0.54, P=0.01), and with clopidogrel AUC(last) on visit 3 (rho=-0.44, P=0.04), and on visit 4 (rho=-0.57, P=0.005). In addition, clopidogrel C(max) was correlated with EPC (CD133+/KDR+) on visit 4 (rho=0.48, P=0.025). No correlations of atorvastatin and MP or EPC were found. CONCLUSIONS: The balance between platelet MP release and EPC mobilization seems influenced by clopidogrel plasma levels, suggesting a protective mechanism on coronary artery disease.

Euterpe oleracea (açai) modifies sterol metabolism and attenuates experimentally-induced atherosclerosis.

AIM: Euterpe Oleracea (açai) is a fruit from the Amazon region whose chemical composition may be beneficial for individuals with atherosclerosis. We hypothesized that consumption of Euterpe Oleracea would reduce atherosclerosis development by decreasing cholesterol absorption and synthesis. METHODS: Male New Zealand rabbits were fed a cholesterol-enriched diet (0.5%) for 12 weeks, when they were randomized to receive Euterpe Oleracea extract (n = 15) or water (n = 12) plus a 0.05% cholesterol-enriched diet for an additional 12 weeks. Plasma phytosterols and desmosterol were determined by ultra-performance liquid chromatography and mass spectrometry. Atherosclerotic lesions were estimated by computerized planimetry and histomorphometry. RESULTS: At sacrifice, animals treated with Euterpe Oleracea had lower levels of total cholesterol (p =0.03), non-HDL-cholesterol (p = 0.03) and triglycerides (p = 0.02) than controls. These animals had smaller atherosclerotic plaque area in their aortas (p = 0.001) and a smaller intima/media ratio (p = 0.002) than controls, without differences in plaque composition. At the end of the study, campesterol, ß-sitosterol, and desmosterol plasma levels did not differ between groups; however, animals treated with Euterpe Oleracea showed lower desmosterol/campesterol (p = 0.026) and desmosterol/ ß-sitosterol (p =0.006) ratios than controls. CONCLUSIONS: Consumption of Euterpe Oleracea extract markedly improved the lipid profile and attenuated atherosclerosis. These effects were related in part to a better balance in the synthesis and absorption of sterols.