High Cholesteryl Ester Transfer Protein Research Articles

Synthesis and Molecular Modeling of Novel 3,5-Bis(trifluoromethyl) benzylamino Benzamides as Potential CETP Inhibitors.

There is an alarming spread of cases of lipid disorders in the world that occur due to harmful lifestyle habits, hereditary risk influences, or as a result of other illnesses or medicines. Cholesteryl Ester Transfer Protein (CETP) is a 476-residue lipophilic glycoprotein that helps in the transport of cholesteryl ester and phospholipids from the atheroprotective HDL to the proatherogenic LDL and VLDL. Inhibition of CETP leads to elevation of HDL cholesterol and reduction of LDL cholesterol and triglycerides; therefore, it is considered a good target for the treatment of hyperlipidemia and its comorbidities. In this research, synthesis, characterization, molecular modeling, and biological evaluation of eight 3,5-bis(trifluoromethyl)benzylamino benzamides 9a-d and 10a-d were carried out. The synthesized molecules were characterized using 1H-NMR, 13C-NMR, IR, and HR-MS. They were biologically tested in vitro to estimate their CETP inhibitory activity. These compounds offered inhibitory effectiveness ranging from 42.2% to 100% at a concentration of 10 μM. Compounds bearing unsubstituted three aromatic rings (9a) or ortho-CF3 substituted (9b) were the most effective compounds among their analogs and showed IC50 values of 1.36 and 0.69 μM, respectively. The high docking scores of 9a-d and 10a-d against 4EWS imply that they might be possible CETP inhibitors. Pharmacophore mapping results demonstrate that the series approves the fingerprint of CETP active inhibitors and therefore explains their high binding affinity against CETP binding site. This work concludes that 3,5-bis(trifluoromethyl)benzylamino benzamides can serve as a promising CETP inhibitor lead compound.

Hibernating brown bears are protected against atherogenic dyslipidemia

To investigate mechanisms by which hibernators avoid atherogenic hyperlipidemia during hibernation, we assessed lipoprotein and cholesterol metabolisms of free-ranging Scandinavian brown bears (Ursus arctos). In winter- and summer-captured bears, we measured lipoprotein sizes and sub-classes, triglyceride-related plasma-enzyme activities, and muscle lipid composition along with plasma-levels of antioxidant capacities and inflammatory markers. Although hibernating bears increased nearly all lipid levels, a 36%-higher cholesteryl-ester transfer-protein activity allowed to stabilize lipid composition of high-density lipoproteins (HDL). Levels of inflammatory metabolites, i.e., 7-ketocholesterol and 11ß-prostaglandin F2α, declined in winter and correlated inversely with cardioprotective HDL2b-proportions and HDL-sizes that increased during hibernation. Lower muscle-cholesterol concentrations and lecithin-cholesterol acyltransferase activity in winter suggest that hibernating bears tightly controlled peripheral-cholesterol synthesis and/or release. Finally, greater plasma-antioxidant capacities prevented excessive lipid-specific oxidative damages in plasma and muscles of hibernating bears. Hence, the brown bear manages large lipid fluxes during hibernation, without developing adverse atherogenic effects that occur in humans and non-hibernators.

Increased Cholesteryl Ester Transfer Protein and Lipoprotein-Associated Phospholipase A2 Activities in Children and Adolescents Presenting High Triglyceride/High-Density Lipoprotein Cholesterol (TG/HDL-C) Ratio.

To explore the association between Triglyceride/High-density lipoprotein cholesterol (TG/HDL-C) index and these enzymes and proteins in a pediatric population. Children and adolescents (7-14 y old) were recruited (n = 150) and anthropometric data were registered. Glucose, TG, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), HDL-C plus cholesteryl ester transfer protein (CETP), lipoprotein-associated phospholipase A2 (Lp-PLA2) and paraoxonase 1 (PON1) activities were determined. Twenty-five individuals presented TG/HDL-C ratio ≥ 3.0. These individuals exhibited higher TG [164 (126-186) vs. 65 (48-72) mg/dL; p < 0.01] CETP [250 (232-263) vs. 223 (193-237)% mL/min; p < 0.01] and Lp-PLA2 (4.5 ± 1.9 vs. 3.5 ± 1.3; p < 0.05) plus lower HDL-C [41 (37-49) vs. 52 (48-62) mg/dL; p < 0.01] compared to an age-matched group with TG/HDL-C < 3.0. TG/HDL-C ratio was associated to CETP (p < 0.01) and Lp-PLA2 (p < 0.05). Multiple lineal regression analyses showed TG/HDL-C index as an independent predictor of CETP (r2 = 0.29; beta = 0.49; p < 0.01) and Lp-PLA2 (r2 = 0.21; beta = 0.32; p < 0.05) activities. Children and adolescents with TG/HDL-C ≥ 3.0 presented a more atherogenic lipid profile and higher CETP and Lp-PLA2 activities, which would indicate alterations in lipoprotein metabolism and quality.

Preoperative plasma biomarkers associated with atrial fibrillation after coronary artery bypass surgery

ObjectivesPostoperative atrial fibrillation (POAF) is a common complication in coronary artery bypass grafting (CABG) procedures. This prospective study aimed to investigate predisposition of proteins and metabolites correlated to POAF after CABG and related cellular pathways. MethodsPreoperative plasma samples from patients undergoing CABG procedures were prospectively collected. After CABG, the patients were grouped to POAF or sinus rhythm (N = 170; n = 90 in the discovery set and n = 80 in the validation set). The plasma samples were analyzed using proteomics, metabolomics, and bioinformatics to identify the differential proteins and differential metabolites. The correlation between differential proteins and POAF was also investigated by multivariable regression analysis and receiver operator characteristic analysis. ResultsIn the POAF(+) group, 29 differential proteins and 61 differential metabolites were identified compared with the POAF(−) group. The analysis of integrated omics revealed that preoperative alteration of peroxisome proliferators-activated receptor α and glutathione metabolism pathways increased the susceptibility of POAF after CABG. There was a correlation between plasma levels of apolipoprotein-C3, phospholipid transfer protein, glutathione peroxidase 3, cholesteryl ester transfer protein, and POAF. ConclusionsThe present study for first time at multi-omics levels explored the mechanism of POAF and validated the results in a new cohort of patients, suggesting preexisting differential proteins and differential metabolites in the plasma of patients prone to POAF after CABG. Dysregulation of peroxisome proliferators-activated receptor α and glutathione metabolism pathways related to metabolic remodeling and redox imbalance-associated electrical remodeling may play a key role in the pathogenesis of POAF. Lower plasma phospholipid transfer protein, apolipoprotein-C3, higher cholesteryl ester transfer protein and glutathione peroxidase 3 levels are linked with POAF. These proteins/metabolites may be developed as biomarkers to predict POAF.

Influence of CETP on High-Density Lipoprotein Subclasses in Patients with Coronary Heart Disease.

Inhibition of plasma cholesteryl ester transfer protein (CETP) can effectively reduce the risk of ath-erosclerotic cardiovascular disease by increasing high-density lipoprotein cholesterol (HDL-C) levels, but the effect of CETP on the distributions of HDL subclasses in patients with coronary heart disease (CHD) is still elusive. To investigate the correlation between the level of CETP and the distributions of HDL subclasses, 121 healthy controls and 139 patients with CHD were selected as study subjects. The plasma levels of CETP and each HDL subclass were respectively determined by enzyme-linked immunosorbent assay and two-dimensional gel electrophoresis associated with the immunodetection method. At the same time, blood biochemical data from all subjects were collected, including the levels of triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), HDL-C, apoA1, and apoB100. Correlation analysis and multiple regression analysis among the plasma HDL subclass values and biochemical parameters in subjects with CHD were conducted. As the plasma level of CETP increases, the contents of TC, TG, and apoB100/A1 were obviously elevated, while the levels of HDL-C and apoA1 decreased significantly. For distributions of HDL subclasses, large-sized HDL2a and HDL2b were markedly decreased in the middle CETP group (p < 0.05) and the high CETP group (p < 0.001) compared to the low CETP group, while the small-sized preβ1-HDL was obviously increased. Intriguingly, when the plasma concentration of TC or TG in patients with CHD was higher, the elevated preβ1-HDL and reduced HDL2a were more dependent on the increase in CETP. Furthermore, correlation analysis and multiple regression analysis also confirmed that plasma CETP was positively correlated with preβ1-HDL levels and negatively correlated with HDL2b levels. The distributions of HDL subclasses were associated with CETP in patients with CHD, especially in those with high levels of TC and TG. CETP levels were associated with an increase in small-sized preβ1-HDL and a decrease in large-sized HDL subclasses, which indicated that CETP might be a limiter of reverse cholesterol transport and HDL maturation.

Reliable structural information for rational design of benzoxazole type potential cholesteryl ester transfer protein (CETP) inhibitors through multiple validated modeling techniques

The drug design and discovery of lipid modulators is very demanding as no new molecule has entered into the market in the last 35 years. Cholesteryl ester transfer protein (CETP) is a promising target as lipid modulators. Inhibition of the CETP enzyme reduces the risk of cardiovascular events. The first CETP inhibitor torcetrapib and related drug candidates failed in the clinical trial due to the off-target effects leading to high toxicity. Thus, newer CETP inhibitors have now paramount importance to accelerate the drug discovery efforts in the field of cardiovascular disease (CVD). In the present study, 140 benzoxazole compounds were studied by using different chemometric techniques, for example, pharmacophore mapping, molecular docking, three-dimensional quantitative structure–activity relationship comparative molecular field analysis (3D-QSAR CoMFA), topomer CoMFA and Bayesian classification, in order to generate complete and reliable information regarding the structural requirements for the CETP inhibition. The best pharmacophore hypothesis was statistically significant (regression coefficient of 0.957 and a lower root mean square of 0.890). Molecular docking study revealed that cyano-substituted compounds form hydrogen bond with targeted macromolecule. The 3D-QSAR CoMFA model also produced a leave-one-out (LOO) cross-validated Q2 of 0.527, an R2 of 0.853 and an R2Pred of 0.603. Similarly, two topomer CoMFA models were also statistically significant and reliable in terms of their Q2, R2 and R2Pred values. The Bayesian classification study also provided the excellent ROC values of 0.919 and 0.939 for training and test sets, respectively. Overall, this study may help in the rational design of newer benzoxazole type compounds with higher CETP inhibition.Communicated by Ramaswamy H. Sarma

HDL cholesterol efflux capacity and cholesteryl ester transfer are associated with body mass, but are not changed by diet-induced weight loss: A randomized trial in abdominally obese men

Background and aimsObesity is associated with a lower HDL-mediated cholesterol efflux from macrophages and a higher CETP (cholesteryl ester transfer protein) activity, but effects of weight loss are not clear. In addition, associations with visceral and subcutaneous adipose tissue are not known. We therefore investigated effects of diet-induced weight loss on HDL-mediated cholesterol efflux and cholesterol ester (CE) transfer in abdominally obese men. Differences between normal-weight and abdominally obese men were also examined. MethodsTwenty-five apparently healthy, normal-weight men (waist circumference: <94 cm) and 52 abdominally obese men (waist circumference: 102–110 cm) were included. Abdominally obese subjects were randomly allocated to a dietary weight-loss intervention group or a no–weight loss control group. Individuals from the intervention group followed a very-low-calorie diet for 6 weeks to obtain a waist circumference below 102 cm, followed by a 2-week weight-stable period. Cholesterol efflux was measured in BODIPY-labeled murine J774 macrophages. CE transfer was measured by quantifying the transfer of CE from radiolabeled exogenous HDL to apoB-containing lipoproteins. ResultsCholesterol efflux capacity was 9 percentage point (pp) lower in abdominally obese than in normal-weight men (p≤0.001), while CE transfer was 5 pp higher (p≤0.01). Diet-induced weight-loss of 10.3 kg did not change cholesterol efflux and CE transfer. In addition, stepwise regression analysis did not suggest that the different fat depots are differently related to efflux capacity and CE transfer. ConclusionsAfter a 2-week weight-stable period, dietary weight loss of 10 kg did not improve ABCA1-mediated cholesterol efflux and CE transfer in abdominally obese men.

Cord and maternal sera from small neonates share dysfunctional lipoproteins with proatherogenic properties: Evidence for Barker's hypothesis

Fetal growth restriction (GR) is associated with perinatal mortality and subsequent metabolic disorders in adulthood. Until now, there is little information regarding changes in the properties of lipoproteins from growth-restricted fetuses and their maternal sera. To identify unique lipoprotein biomarkers for fetal GR in maternal and cord sera from small neonates, we analyzed lipoprotein compositions and functions. Lipoprotein compositions and functions were compared between cord blood and maternal blood among small for gestational age neonates (SGA; n=15, 2589±50g) and appropriate for gestational age neonates (AGA; n=15) in Korea. Cord blood from the SGA group showed 2-fold higher triglyceride (TG) and TG/high-density lipoprotein cholesterol levels than the AGA group as well as significantly lower (up to 20%) paraoxonase activity and apolipoprotein (apo) A-I content. The SGA group showed the highest cholesteryl ester transfer protein activities in both cord and maternal sera. SGA neonates showed elevated apo-B content in very low-density lipoprotein, 52% reduction of apo A-I content in high-density lipoprotein, and 30% increased glycation (P<.001) compared with AGA neonates. Especially, low-density lipoprotein from the SGA group showed 1.9-fold higher sensitivity to oxidation as well as 3-fold greater uptake into macrophages, suggesting stronger proatherosclerotic properties. Lipoproteins from maternal serum of SGA neonates showed greater oxidation along with TG enrichment and loss of antioxidant ability. On microinjection of cord serum (50nL) into zebrafish embryos, the SGA group showed the most severe embryonic damage. Lipoproteins from cord and maternal sera of SGA neonates resulted in severe impairment of functional and structural correlations accompanied by greater pro-oxidant and proatherosclerotic properties.

Dalcetrapib and anacetrapib differently impact HDL structure and function in rabbits and monkeys

Inhibition of cholesteryl ester transfer protein (CETP) increases HDL cholesterol (HDL-C) levels. However, the circulating CETP level varies and the impact of its inhibition in species with high CETP levels on HDL structure and function remains poorly characterized. This study investigated the effects of dalcetrapib and anacetrapib, the two CETP inhibitors (CETPis) currently being tested in large clinical outcome trials, on HDL particle subclass distribution and cholesterol efflux capacity of serum in rabbits and monkeys. New Zealand White rabbits and vervet monkeys received dalcetrapib and anacetrapib. In rabbits, CETPis increased HDL-C, raised small and large α-migrating HDL, and increased ABCA1-induced cholesterol efflux. In vervet monkeys, although anacetrapib produced similar results, dalcetrapib caused opposite effects because the LDL-C level was increased by 42% and HDL-C decreased by 48% (P < 0.01). The levels of α- and preβ-HDL were reduced by 16% (P < 0.001) and 69% (P < 0.01), resulting in a decrease of the serum cholesterol efflux capacity. CETPis modulate the plasma levels of mature and small HDL in vivo and consequently the cholesterol efflux capacity. The opposite effects of dalcetrapib in different species indicate that its impact on HDL metabolism could vary greatly according to the metabolic environment.

The effect of cholesteryl ester transfer protein on pancreatic beta cell dysfunction in mice.

BackgroundCholesterol accumulation causes pancreatic beta cell lipotoxicity and dysfunction. Cholesteryl ester transfer protein (CETP) plays an important role in blood lipid homeostasis. However, its role in tissue lipid metabolism remains unclear. We hypothesized that plasma CETP impact cholesterol homeostasis in the beta cells, thus damaging their functions.MethodsThe adipose tissue-specific CETP expression transgenic (aP2-CETPTg) mice, characterized by high CETP levels in the circulation, were used in this study. Pancreatic islet cholesterol and beta cell function were assessed in mice. We further measured mRNA levels of the genes involved in beta cell proliferation and differentiation, inflammation and cholesterol metabolism. TUNEL assay was applied to investigate beta cell apoptosis in islets.ResultsThe aP2-CETPTg mice exhibited glucose intolerance, lower plasma insulin concentrations but increased insulin sensitivity compared with wild type mice. In addition, glucose-stimulated insulin secretion from isolated pancreatic islets significantly decreased, and free cholesterol significantly increased. Moreover, the number and size of islets from aP2-CETPTg mice were significantly decreased. Genes involved in beta cell proliferation, such as Pdx1 and BETA2, were down-regulated; genes involved in inflammation and ER stress, such as IL-1β, CHOP, and Xbp1 were up-regulated, in line with an increase of beta cell apoptosis.ConclusionsPlasma CETP causes free cholesterol accumulation in islets which could contribute to beta cell dysfunction. Thus, CETP inhibition could be a novel protective strategy for dyslipidemia related to diabetes and obese.

2D and 3D QSAR models for identifying diphenylpyridylethanamine based inhibitors against cholesteryl ester transfer protein.

Cholesteryl ester transfer protein (CETP) inhibitors hold promise as new agents against coronary heart disease. Molecular modeling techniques such as 2D-QSAR and 3D-QSAR analysis were applied to establish models to distinguish potent and weak CETP inhibitors. 2D and 3D QSAR models-based a series of diphenylpyridylethanamine (DPPE) derivatives (newly identified as CETP inhibitors) were then performed to elucidate structural and physicochemical requirements for higher CETP inhibitory activity. The linear and spline 2D-QSAR models were developed through multiple linear regression (MLR) and support vector machine (SVM) methods. The best 2D-QSAR model obtained by SVM gave a high predictive ability (R(2)train=0.929, R(2)test=0.826, Q(2)LOO=0.780). Also, the 2D-QSAR models uncovered that SlogP_VSA0, E_sol and Vsurf_DW23 were important features in defining activity. In addition, the best 3D-QSAR model presented higher predictive ability (R(2)train=0.958, R(2)test=0.852, Q(2)LOO=0.734) based on comparative molecular field analysis (CoMFA). Meanwhile, the derived contour maps from 3D-QSAR model revealed the significant structural features (steric and electronic effects) required for improving CETP inhibitory activity. Consequently, twelve newly designed DPPE derivatives were proposed to be robust and potent CETP inhibitors. Overall, these derived models may help to design novel DPPE derivatives with better CETP inhibitory activity.

Elevated CETP activity during acute phase of myocardial infarction is independently associated with endothelial dysfunction and adverse clinical outcome

Objective: Recent data suggests that cholesteryl ester transfer protein (CETP) activity may interact with acute stress conditions via inflammatory-oxidative response and thrombogenesis. We investigated this assumption in patients with ST-elevation myocardial infarction (STEMI). Methods: Consecutive patients with STEMI (n = 116) were enrolled <24-h of symptoms onset and were followed for 180 days. Plasma levels of C-reactive protein (CRP), interleukin-2 (IL-2), tumor necrosis factor (TNFα), 8-isoprostane, nitric oxide (NOx) and CETP activity were measured at enrollment (D1) and at fifth day (D5). Flow-mediated dilation (FMD) was assessed by ultrasound and coronary thrombus burden (CTB) was evaluated by angiography. Results: Neither baseline nor the change of CETP activity from D1 to D5 was associated with CRP, IL-2, TNFα, 8-isoprostane levels or CTB. The rise in NOx from D1 to D5 was inferior [3.5(−1; 10) vs. 5.5(−1; 12); p < 0.001] and FMD was lower [5.9(5.5) vs. 9.6(6.6); p = 0.047] in patients with baseline CETP activity above the median value than in their counterparts. Oxidized HDL was measured by thiobarbituric acid reactive substances (TBARS) in isolated HDL particles and increased from D1 to D5, and remaining elevated at D30. The change in TBARS content in HDL was associated with CETP activity (r = 0.72; p = 0.014) and FMD (r = −0.61; p = 0.046). High CETP activity at admission was associated with the incidence of sudden death and recurrent MI at 30 days (OR 12.8; 95% CI 1.25–132; p = 0.032) and 180 days (OR 3.3; 95% CI 1.03–10.7; p = 0.044). Conclusions: An enhanced CETP activity during acute phase of STEMI is independently associated with endothelial dysfunction and adverse clinical outcome.

CETP inhibitors and cardiovascular disease: Time to think again

Inhibition of cholesteryl ester transfer protein (CETP) lowers plasma low-density lipoprotein cholesterol concentration and raises high-density lipoprotein (HDL) cholesterol, suggesting it might prevent cardiovascular disease (CVD). From the outset, however, the concept has been controversial owing to uncertainty about its effects on HDL function and reverse cholesterol transport (RCT). Although there has long been good evidence that CETP inhibition reduces atherosclerosis in rabbits, the first information on CETP as a CVD risk factor in a prospectively followed cohort was not published until after the first Phase 3 trial of a CETP inhibitor had begun. The worrying finding that CVD incidence was related inversely to plasma CETP has since been reproduced in each of five further prospective cohort studies. Similar results were obtained in subjects on or off statin therapy, for first and second CVD events, and for mortality as well as CVD morbidity. Additionally, two recent studies have found alleles of the CETP gene that lower hepatic CETP secretion to be associated with an increased risk of myocardial infarction. Meanwhile, CETP gene transfer in mice was found to increase RCT from peripheral macrophages in vivo, and human plasma with high CETP activity was shown to have a greater capacity to remove cholesterol from cultured cells than plasma with low activity. This mounting evidence for a protective function of CETP has been given remarkably little attention, and indeed was not mentioned in several recent reviews. It appears to show that CETP inhibition does not test the HDL hypothesis as originally hoped, and raises a pressing ethical issue regarding two Phase 3 trials of inhibitors, involving more than forty thousand subjects, which are currently in progress. As the weight of evidence now clearly supports an adverse effect of CETP inhibition on CVD, an urgent review is needed to determine if these trials should be discontinued.

CETP inhibitors and cardiovascular disease: Time to think again

Inhibition of cholesteryl ester transfer protein (CETP) lowers plasma low-density lipoprotein cholesterol concentration and raises high-density lipoprotein (HDL) cholesterol, suggesting it might prevent cardiovascular disease (CVD). From the outset, however, the concept has been controversial owing to uncertainty about its effects on HDL function and reverse cholesterol transport (RCT). Although there has long been good evidence that CETP inhibition reduces atherosclerosis in rabbits, the first information on CETP as a CVD risk factor in a prospectively followed cohort was not published until after the first Phase 3 trial of a CETP inhibitor had begun. The worrying finding that CVD incidence was related inversely to plasma CETP has since been reproduced in each of five further prospective cohort studies. Similar results were obtained in subjects on or off statin therapy, for first and second CVD events, and for mortality as well as CVD morbidity. Additionally, two recent studies have found alleles of the CETP gene that lower hepatic CETP secretion to be associated with an increased risk of myocardial infarction. Meanwhile, CETP gene transfer in mice was found to increase RCT from peripheral macrophages in vivo , and human plasma with high CETP activity was shown to have a greater capacity to remove cholesterol from cultured cells than plasma with low activity. This mounting evidence for a protective function of CETP has been given remarkably little attention, and indeed was not mentioned in several recent reviews. &nbsp;It appears to show that CETP inhibition does not test the HDL hypothesis as originally hoped, and raises a pressing ethical issue regarding two Phase 3 trials of inhibitors, involving more than forty thousand subjects, which are currently in progress. As the weight of evidence now clearly supports an adverse effect of CETP inhibition on CVD, an urgent review is needed to determine if these trials should be discontinued.

CETP inhibitors and cardiovascular disease: Time to think again.

Inhibition of cholesteryl ester transfer protein (CETP) lowers plasma low-density lipoprotein cholesterol concentration and raises high-density lipoprotein (HDL) cholesterol, suggesting it might prevent cardiovascular disease (CVD). From the outset, however, the concept has been controversial owing to uncertainty about its effects on HDL function and reverse cholesterol transport (RCT). Although there has long been good evidence that CETP inhibition reduces atherosclerosis in rabbits, the first information on CETP as a CVD risk factor in a prospectively followed cohort was not published until after the first Phase 3 trial of a CETP inhibitor had begun. The worrying finding that CVD incidence was related inversely to plasma CETP has since been reproduced in each of five further prospective cohort studies. Similar results were obtained in subjects on or off statin therapy, for first and second CVD events, and for mortality as well as CVD morbidity. Additionally, two recent studies have found alleles of the CETP gene that lower hepatic CETP secretion to be associated with an increased risk of myocardial infarction. Meanwhile, CETP gene transfer in mice was found to increase RCT from peripheral macrophages in vivo, and human plasma with high CETP activity was shown to have a greater capacity to remove cholesterol from cultured cells than plasma with low activity. This mounting evidence for a protective function of CETP has been given remarkably little attention, and indeed was not mentioned in several recent reviews. It appears to show that CETP inhibition does not test the HDL hypothesis as originally hoped, and raises a pressing ethical issue regarding two Phase 3 trials of inhibitors, involving more than forty thousand subjects, which are currently in progress. As the weight of evidence now clearly supports an adverse effect of CETP inhibition on CVD, an urgent review is needed to determine if these trials should be discontinued.

Novel derivatives of monascus pigment having a high CETP inhibitory activity

The cholesteryl ester transfer protein (CETP), inhibition of which assists in maintaining a high level of high-density lipoprotein cholesterol in the blood, is a target for anti-atherosclerosis treatments. Orange monascus pigment was produced by a Monascus species in a 5 L jar fermenter and various derivative compounds were synthesised by incorporating 19 different l-amino acids into the orange pigment. Among them, the l-Thr and l-Tyr derivatives exhibited high inhibitory activities against the CETP reaction. The inhibitory activities of the l-Thr and l-Tyr derivatives increased in a dose-dependent manner, resulting in IC50 values of 1.0 and 2.3 μM, respectively. When CETP reactions in the presence of the derivatives were performed, the inhibition modes of the l-Thr and l-Tyr derivatives were non-competitive with inhibition constant (Ki) values of 2.7 and 4.3 μM, respectively.

Decreased cholesterol efflux capacity in patients with low cholesteryl ester transfer protein plasma levels

Cholesteryl ester transfer protein (CETP) has been considered as a possible target for treatment of cardiovascular disease. However, first clinical studies employing CETP inhibitors have failed to demonstrate clinical benefit. Additionally, we have previously shown that low endogenous plasma levels of CETP are associated with increased mortality in coronary artery disease (CAD) patients. We hypothesized that low CETP plasma levels are associated with decreased high-density lipoprotein (HDL) function. Serum HDL efflux capacity was measured in 154 patients of the Ludwigshafen Risk and Cardiovascular Health (LURIC) study displaying extremely low (< 0·68 μg/mL, n = 77) or high (> 2·13 μg/mL, n = 77) CETP concentrations in their plasma, respectively. The LURIC study is a prospective observational study of patients referred to coronary angiography at baseline with a median follow-up time of 7·75 years. Primary and secondary endpoints were cardiovascular and all-cause mortality, respectively. High CETP patients showed a significant increase in the capacity of their plasma to mediate cholesterol efflux from cholesterol laden macrophages when compared to the efflux capacity observed in low CETP patients (+ 5·4%, P = 0·015). As shown by multiregression analysis, the impact of CETP on cholesterol efflux capacity was independent from classical risk and lifestyle factors, as well as from lipid parameters including HDL cholesterol, LDL cholesterol and triglycerides. Our findings indicate that low plasma concentrations of CETP might indeed lead to impaired HDL function within the reverse cholesterol transport pointing towards an atheroprotective role of CETP at least in patients with high risk of CAD.

PS13 - 7. Plasma cholesteryl ester transfer protein: a biomarker for hepatic macrophages

Cholesteryl ester transfer protein (CETP) transfers cholesteryl esters from HDL to LDL and high CETP activity results in an atherogenic lipid phenotype. Thus, inhibiting CETP is a target for dyslipidemia treatment. However, the true origin of CETP in humans is uncertain. We aimed to elucidate the cellular origin of CETP and the relative contribution of adipose tissue and liver to plasma CETP levels.

High cholesteryl ester transfer protein (CETP) activity in acute phase of myocardial infarction predicts short-term mortality by inducing endothelial dysfunction and reduced microvascular perfusion

Background: Recently, much effort has been centered on the development of cholesteryl ester transfer protein (CETP) inhibitors, based on CETP proatherogenic role. However, some evidence indicates exacerbated CETP activity (CETPa) may also favor arterial thrombogenicity and impair endothelial function. In this context, we investigated the relation between CETPa and: 1) endothelial dysfunction; 2) coronary blood flow/myocardial perfusion after reperfusion therapy in patients with ST-elevation myocardial infarction (STEMI). Methods: Consecutive thrombolytic-treated STEMI patients (n=116) were followed prospectively. Plasma C-reactive protein (CRP), IL-2, TNFα, 8-isoprostane, nitric oxide (NOx) levels and CETPa (%) were measured in the first 24 hours (D1) and at 5th day (D5) after MI onset. Culprit artery percutaneous coronary angioplasty (PCA) was performed at a mean 6 days after MI, when pre- and post-procedure myocardial blush grade (MBG) and TIMI flow were measured. At D30 we measured brachial artery flow-mediated dilation (FMD) by ultrasonography. In addition, all patients were genotyped for eNOS polymorphism rs1799983 (G/T). Results: Although admission CETPa had no relation with the change between D1 and D5 in CRP, IL-2, TNFα or 8-isoprostane plasma levels, patients with higher CETPa presented both poor coronary flow (TIMI flow<3, adjusted OR of 22.1 95% CI 2.7–180; p=0.004) and myocardial perfusion (MBG<3, OR 20.4 CI 1.8–101; p=0.001), compared to those with lower CETP activity. Logistic regressions showed admission plasma CETPa higher than median as an independent predictor of cardiac death and new MI in 30 days (OR=12.8, CI 1.25–132, p=0.032), as well as endothelial dysfunction (OR=3.08, CI 1.01–9.37,p=0.048). Consistently, the rise in NOx levels between D1 and D5 was less intense in patients with exacerbated CETPa (5.5 (-1; 12) vs 3.5 (-1; 10); p<0.001). In addition, in order to evaluate if eNOS activity would be critical for the association between CETP and endothelial dysfunction, we observed that only in the presence of the functional eNOS T allele polymorphism the correlation between CETP and FMD was maintained (R2=-0.4, p=0.002). T allele patients with admission CETPa lower than median also presented FMD of 12.2±4 vs 6.0±3mm in those with high CETPa (p=0.040). Conclusions: This is the first study to suggest a relation between high plasma CETP activity in acute STEMI and increased clinical outcomes at 30 days. Our study also indicates a positive association between exacerbated CETP activity in MI and both endothelial dysfunction and poor reperfusion quality post-angioplasty.

Low normal thyroid function enhances plasma cholesteryl ester transfer in Type 2 diabetes mellitus

BackgroundPlasma cholesteryl ester transfer (CET), reflecting endogenous transfer of cholesteryl esters from HDL to very low and low density lipoproteins, is elevated in Type 2 diabetes mellitus (T2DM), and may predict (subclinical) cardiovascular disease. Low normal thyroid function may adversely affect lipoprotein metabolism and atherosclerosis development. We tested whether plasma CET is related to thyroid function in euthyroid T2DM and non-diabetic subjects. Subjects and methodsPlasma CET was measured in 74 T2DM and 82 non-diabetic subjects with thyroid-stimulating hormone (TSH) and free thyroxine levels within the reference range. ResultsPlasma CET was 20% higher in T2DM (P = 0.003) coinciding higher cholesteryl ester transfer protein (CETP) mass (P = 0.009) and triglycerides (P = 0.02). In univariate analysis, plasma CET was correlated positively with TSH in T2DM only (r = 0.330, P = 0.004). Multiple linear regression analysis revealed a positive interaction between the presence of T2DM and TSH on plasma CET after controlling for age, sex, body mass index, non-HDL cholesterol, triglycerides and CETP mass (β = 0.167, P = 0.030). The relationship of plasma CET with TSH was also positively modified by plasma glucose and HbA1c (interaction terms: β = 0.119, P = 0.036, β = 0.170, P = 0.001, respectively). Additionally, plasma triglycerides interacted positively with TSH on plasma CET in T2DM (β = 0.198, P = 0.011). ConclusionsLow normal thyroid function, as inferred from higher TSH, confers increased plasma CET in the context of chronic hyperglycemia. Effects of thyroid function on plasma CET may be particularly relevant in hypertriglyceridemic T2DM. Low normal thyroid function could influence atherosclerosis susceptibility in T2DM by affecting the plasma cholesteryl ester transfer process.