Hyperlipidemias: Auteri A

Puccetti L, Acampa M, Auteri A. · Department of Clinical Medicine and Immunological Sciences, Section of Internal Medicine, University of Siena, Siena, Italy. · Recent Pat Cardiovasc Drug Discov. · Pubmed #18221122 No free full text.

Abstract: Cardiovascular disease has become the global leading cause of death worldwide, representing the most frequent cause of morbidity and mortality in the developed world. Statins, the most widely prescribed cholesterol-lowering drugs, are considered to be first-line therapeutics for the prevention of coronary heart disease and atherosclerosis. Meta-analyses from several primary and secondary intervention studies have clearly shown that cholesterol-lowering medication, significantly reduces cardiovascular events, mortality, and morbidity, but considerable interindividual variation exists in response to statin therapy. Pharmacogenomics can provide important insights into statins therapy through elucidation of the genetic (or genomic) contribution to variable response for these drugs. The search for genetic polymorphisms may enable us to identify novel determinants of drug responsiveness by means of the study of three candidate genes groups: (1) genes encoding proteins involved in metabolism or drug transport, or both, that influence drug pharmacokinetics; (2) genes encoding proteins involved in mechanism of action and/or metabolic pathways on which drugs operate (that influence pharmacodynamics); (3) genes encoding proteins involved in the underlying disease condition or intermediate phenotype. This review briefly summarizes the recent pharmacogenomic and pharmacogenetic patents and the potential contributions of genetic variations in candidate genes related to lipid and lipoprotein metabolism and statins efficacy.

Puccetti L, Bruni F, Pasqui AL, Pastorelli M, Ciani F, Palazzuoli A, Acampa M, Auteri A. · Department of Clinical Medicine and Immunology, Internal Medicine Division, Centre for Atherosclerosis Research, University of Siena, Siena, Italy. · Eur J Clin Invest. · Pubmed #18173546 No free full text.

Abstract: BACKGROUND: Recent data indicate that statins could offer coronary artery disease (CAD) benefit even by mechanisms beyond lipid lowering. Genetic influence has been shown for some antithrombotic actions of statins via oxidized-low-density lipoprotein cholesterol (ox-LDL) receptors and nitric oxide synthase (NOS) activity modulation. The present study was designed to evaluate the influence of ox-LDL lectin-like receptor-1 (LOX-1) and NOS polymorphisms in the incidence of cardiovascular events in pure hypercholesterolaemic subjects during statin treatment. MATERIALS AND METHODS: A prospective 4-year study involving 1039 event-free subjects (643 males, 396 females) treated with atorvastatin (10-40 mg day(-1)) to reach the appropriate Adult Treatment Panel-III LDL target of 3.36 mmol L(-1). Enrolled subjects were evaluated every 6 months or at a clinical event. LOX-1 3'UTR/T-C and NOS G894T polymorphisms were detected by allelic discrimination assays (polymerase chain reaction), lipid profile by enzymatic-colorimetric method, ox-LDL by enzyme linked immunosorbent assay, platelet activation by P-selectin (P-sel) expression (FACScan), NOS activity (by intracellular citrullin recovery) and homocysteine (high performance liquid chromatography), C-reactive protein (CRP) by sensitive nephelometric technique. RESULTS: LOX-1 3'UTR/T showed the strongest association with events in the whole cohort with respect to each other variable including LDL reduction and NOS G894T (OR 4.90, 95% CI 3.19-6.98, P < 0.00001). Smoking influenced events in LDL-targeted subjects (P < 0.0001). Ox-LDL and P-sel were better indicators than LDL or other variables according to 3'UTR/C genotype regardless of the magnitude of LDL reduction (OR 4.21, 95% CI 2.29-6.70 P < 0.0001). CONCLUSIONS: LOX-1 polymorphisms could influence statin effectiveness in CAD prevention by induction of sensitivity to antithrombotic mechanisms such as antiplatelet activity.

Bruni F, Pasqui AL, Pastorelli M, Bova G, Cercignani M, Palazzuoli A, Sawamura T, Gioffre WR, Auteri A, Puccetti L. · Department of Clinical Medicine and Immunological Sciences, Internal Medicine Division, Center for Atherosclerosis Research, University of Siena, Siena, Italy. · Clin Appl Thromb Hemost. · Pubmed #16244767 No free full text.

Abstract: Hydroxymethyl-glutaryl-CoA-reductase inhibitors (statins) reduce cardiovascular mortality by decreasing cholesterol as well as by non-lipid-related actions. Oxidized low-density lipoproteins (ox-LDL) are pro-atherogenic molecules and potent platelet agonists. CD36 and lectin-like ox-LDL receptor-1 (LOX-1) are specific ox-LDL receptors also expressed in platelets. This study was planned to address whether treatment with atorvastatin 10 mg/day, pravastatin 40 mg/day or simvastatin 20 mg/day could affect platelet CD36 and LOX-1 expression. Twenty-four patients for each treatment were evaluated after 3, 6, and 9 days and at 6 weeks for complete lipid profile (chromogenic), ox-LDL (ELISA), platelet P-selectin (P-sel), CD36, LOX-1 (FACS), and intracellular citrullin recovery (iCit) (HPLC). Data show hyperactivated platelets (P-sel absolute values, percent variation in activated cells, all p < 0.001), and CD36 and LOX-1 overexpression (all p < 0.001) in patients at baseline. P-sel, CD36, and LOX-1 were significantly decreased by atorvastatin and simvastatin (all p < 0.01) and related with iCit increase (r = 0.58, p < 0.001) and platelet-associated ox-LDL (r = 0.51, p < 0.01) at 9 days. Pravastatin reduced LOX-1 and P-sel (p < 0.05) at 6 weeks in relation with decreased LDL and ox-LDL (r = 0.39, p < 0.01 and r = 0.37, p < 0.01, respectively). These data suggest that atorvastatin and simvastatin reduce platelet activity by exposure of CD36 and LOX-1 before significant LDL reduction, whereas pravastatin action is detected later and in relation with LDL and ox-LDL lowering. Rapid and consistent reduction of CD36 and LOX-1 could be considered a direct anti-atherothrombotic mechanism related to the role of ox-LDL in platelet activation, platelet-endothelium interactions, and NO synthase activity.

Bruni F, Pasqui AL, Pastorelli M, Bova G, Di Renzo M, Cercigani M, Leo A, Auteri A, Puccetti L. · Department of Clinical Medicine and Immunological Sciences, Internal Medicine Division, Center for Metabolic Diseases and Atherosclerosis, University of Siena, Policlinico Le Scotte, V.le Bracci, 53100 Siena, Italy. · Int J Cardiol. · Pubmed #15193831 No free full text.

Abstract: BACKGROUND: Hydroxymethyl-glutaryl-CoA-reductase inhibitors (statins) reduce cardiovascular events by cholesterol lowering as well as non-lipid related actions. Among them, the modulation of fibrinolysis could play a relevant role in vascular protection. Atorvastatin is able of reducing platelet activity and thrombin generation before low-density lipoprotein cholesterol (LDL-C) decrease in hypercholesterolemic subjects in which coagulation and fibrinolysis are linked by the activation of thrombin activable fibrinolysis inhibitor (TAFI). The aim of our study was to evaluate whether atorvastatin could modulate fibrinolysis by interactions with endothelial mechanisms and thrombin generation. METHODS: Forty-four pure hypercholesterolemic subjects (26 M, 18 F, mean age 52.7+/-13.7, LDL-C 194.8+/-9.3t mg/dl) were evaluated for plasmin-antiplasmin complexes (PAP), tissue-plasminogen acivator (t-PA) and its inhibitor (PAI-1) (ELISA), TAFI activity (HPLC), platelet P-selectin (P-sel) (cytofluorymetric detection), platelet-dependent thrombin generation (PDTG, coagulative-chromogenic method) and lipid profile at baseline and after 7, 14, 28 and 90 days of atorvastatin (10 mg/die) treatment. RESULTS: PAP were significantly reduced at baseline in hypercholesterolemic versus control subjects (P<0.05) and were related to P-sel (P<0.01), PDTG (P<0.01) and its inhibitor (PAI-1) after venous occlusion (VO) (P<0.05). Atorvastatin induced a significant increase of PAP at T(2) related to modifications of P-sel (P<0.01) and PDTG (P<0.01) before significant LDL-C reduction (P=0.132). PAI-1 was significantly changed at T(3) with relation to LDL-C (P<0.01), Von Willebrand factor (VWF) (P<0.01) and sE-sel (P<0.05). CONCLUSIONS: The profibrinolytic activity of atorvastatin in hypercholesterolemic subjects is related, initially, to the positive effects exerted on platelet function and thrombin generation which can modulate fibrinolysis by TAFI activity.

Puccetti L, Pasqui AL, Pastorelli M, Bova G, Di Renzo M, Leo A, Cercignani M, Palazzuoli A, Auteri A, Bruni F. · Department of Clinical Medicine and Immunological Sciences, Internal Medicine Division, Policlinico Le Scotte, V. le Bracci, 53100, Siena, Italy. · Thromb Haemost. · Pubmed #12958617 No free full text.

Abstract: Hydroxymethyl-glutaryl-CoA-reductase inhibitors (statins) reduce cardiovascular events by cholesterol lowering as well as by non-lipid related actions. Among them, the modulation of platelet activity could play a relevant role in vascular protection. Furthermore withdrawal of statins has been associated with increased cardiovascular event rate. The aim of our study was to evaluate platelet activity after cerivastatin discontinuation in eighteen subjects that did not accept other drugs and in sixteen subjects continuing treatment with simvastatin. Fourteen subjects at the end of the discontinuation period decided to receive other drugs (simvastatin) and they were evaluted six weeks later. We measured complete lipid profile by the chromogenic method (LDL-C was calculated); oxidized-LDL (ox-LDL; ELISA), platelet P-selectin (P-sel) expression (flow cytometry detection), platelet aggregation (% change of transmitted light), intracellular citrullin production (iCit; HPLC) as an indicator of intracellular NO synthase activity at baseline and 7, 14, 28, 60 days after statin discontinuation. P-sel expression and platelet aggregation were increased at 14 days (p < 0.001 and p < 0.05) in association with raised ox-LDL (r = 0.30, p < 0.05) and decreased iCit (r = 0.53, p < 0.01). Increased LDL-C was related to P-sel and platelet aggregation at 28 days (r = 0.30, p < 0.05). Subjects continuing statin treatment had no significant changes of P-sel at 28 (p = 0.221) and 60 days (p = 0.238). Subjects treated with simvastatin after 60 days of diet showed a significant reduction of P-sel and platelet aggregation after six weeks of treatment (p < 0.01). Our data suggest a platelet hyperactivation state in the second week after statin discontinuation which is partially related to raised LDL-C. Such a finding could participate in the increased cardiovascular event rate after statin discontinuation.

Puccetti L, Pasqui AL, Pastorelli M, Bova G, Cercignani M, Palazzuoli A, Angori P, Auteri A, Bruni F. · Department of Clinical Medicine and Immunological Sciences, Center for Metabolic Diseases and Atherosclerosis, University of Siena, Siena, Italy. · Eur J Clin Invest. · Pubmed #12534449 No free full text.

Abstract: BACKGROUND: Reduction of platelet activity induced by statins has been described as a positive effect exerted by such molecules on vascular thrombotic events. However, the relations among cholesterol (LDL-C) reduction, the timing of the antiplatelet effect, the involved mechanisms and the doses of each statin able to reduce platelet function are not actually well known. The aim of our study was to evaluate the impact of simvastatin (20 mg day-1), atorvastatin (10 mg day-1), fluvastatin (40 mg day-1) and pravastatin (40 mg day-1) on platelet function in hypercholesterolaemic subjects with relation to (LDL-C), oxidized-LDL (ox-LDL) and antiport mechanism modifications. MATERIALS AND METHODS: Sixteen subjects were assigned to each treatment (40 males, 24 females, mean age 48.7 +/- 13.4, LDL-C 5.13 +/- 0,23 mmol L-1) and evaluated for platelet surface P-selectin (P-sel), lipid profile, ox-LDL, platelet-associated ox-LDL (Pox-LDL), platelet cholesterol content, antiport mechanisms, and intracellular and systemic NO synthase every 7 days for one month. RESULTS: Our data show a strong relation between enhanced P-sel and Pox-LDL (r = 0.68, P < 0.01). Simvastatin, atorvastatin, fluvastatin and pravastatin reduce platelet activity after 1, 2, 3 and 4 weeks of treatment, respectively (P < 0.001, P < 0.001, P < 0.01, P < 0.05). Pox-LDL are modulated early by simvastatin, atorvastatin and fluvastatin Pox-LDL (r = 0.66, 0.65 and 0.52; P < 0.001, 0.001 and 0.01, respectively) whereas LDL-C and ox-LDL reductions associated to modifications of antiport activity act later. Moreover, they are the most relevant finding in pravastatin-related subjects. CONCLUSIONS: Our data suggest a different impact of several statins on platelet function, which is initially related to interference with Pox-LDL rather than LDL-C reduction.

Puccetti L, Bruni F, Bova G, Cercignani M, Palazzuoli A, Console E, Auteri A, Pasqui AL. · Institute of Medical Semeiotics, Centro per lo Studio delle Malattie Dismetaboliche e della Aterosclerosi, University of Siena, Siena, Italy. · Nutr Metab Cardiovasc Dis. · Pubmed #12055702 No free full text.

Abstract: BACKGROUND AND AIM: Platelets are strictly involved in arterial thrombosis and their hyperactivity has been shown in hypercholesterolemia. It has been reported that drugs affecting cholesterol metabolism (statins) decrease cardiovascular events by lowering lipid levels or by means of non-lipidic actions such as the direct inhibition of platelet function. The aim of this study was to detect the effect on platelet-dependent thrombin generation (PDTG) of a reduction in cholesterol obtained by means of a lipid-lowering diet or treatment with statins. METHODS AND RESULTS: We compared PDTG (T0) in 144 hypercholesterolemic subjects (94 males and 50 females of child-bearing age, mean age 48.2 +/- 13.8, plasma total cholesterol 6.93 +/- 0.64, high density lipoprotein cholesterol 1.25 +/- 0.14, triglycerides 1.15 +/- 0.19 mmol/L) and 70 normolipidemic controls (37 males and 33 females, mean age 43.1 +/- 12.6. After six weeks on an appropriate diet, the patients were randomised to receive different statin therapies if there was no reduction in their lipid profile and/or PDTG (T1). They were re-evaluated six weeks later, and the drug doses were maintained or increased on the basis of the variables (T2). A final evaluation was made after a further six weeks (T3). All of the data were evaluated using ANOVA and Spearman's correlation coefficent. The results showed increased PDTG in hypercholesterolemic subjects (418.2 +/- 29.2 mIU/mL, p < 0.001 vs controls). Diet alone did not reduce PDTG (380.2 +/- 28.5 mIU/mL, p = 0.226 vs controls). At T2, simvastatin and atorvastatin significantly decreased PDTG (P < 0.001 vs T0-1) and low-density lipoprotein cholesterol (LDL-C). No correlation was found between the two variables in the simvastatin group (r = 0.16). Cerivastatin reduced PDTG without significantly decreasing LDL-C (p < 0.001 and p = 0.476, r = 0.14). Pravastatin and fluvastatin significantly reduced thrombin generation only at T3 (40 mg/day); pravastatin was also associated with a decrease in LDL-C (p < 0.01, r = 0.66). CONCLUSIONS: Our results confirm an increased PDTG in patients with type IIa hyperlipoproteinemia, which is not reduced by diet. Statins at different doses significantly decrease PDTG but do not correlate with a reduction in LDL-C.

Puccetti L, Bruni F, Di Renzo M, Bova G, Cercignani M, Iadanza A, Auteri A, Pasqui AL. · Institute of Medical Semeiotics, Centro per lo Studio delle Malattie Dismetaboliche e della Aterosclerosi, University of Siena, Italy. · Eur Rev Med Pharmacol Sci. · Pubmed #11075617 No free full text.

Abstract: BACKGROUND: Hypercholesterolemia is an important risk factor to develop acute thrombotic complications of atherosclerosis like to myocardial infarction and ischemic stroke. Platelets and coagulation factors are strictly involved in the genesis of such thrombotic events and their hyperactivity in hypercholesterolemic patients has been previously reported. Moreover some cholesterol-lowering molecules (statins) seem to be able of reducing platelet activity. METHODS: We performed platelet-dependent thrombin generation (colorimetric method) to assess the coagulative potential of 40 caucasian hypercholesterolemic subjects with respect to normal controls and to the grade of hypercholesterolemia. Moreover we observed the effect of platelets from hypercholesterolemics on thrombin generation in plasma from normal subjects. The effect of Cerivastatin on thrombin generation was evaluated too. RESULTS: Our data show an increased thrombin generation both in mild and high hypercholesterolemic subjects with respect to controls (424.6+/-30.5 vs. 197.1+/-27.4 mIU/ml). No significant difference in the amount of thrombin generation was found between mild and high hypercholesterolemics (399.6+/-20.7 vs. 440.2+/-21.4 mIU/ml). Platelets directly influence thrombin generation and they present an intrinsic hyperactivity that can be modulated by Cerivastatin (223.6+/-24.8 vs. 424.6+/-30.5 mIU/ml). CONCLUSIONS: Mild hypercholesterolemia is associated with an increased thrombinic potential that may be considered an added risk factor to develop thrombotic events. Platelets directly influences this hypercoagulative state and Cerivastatin is able to reduce thrombin generation by way of a direct interaction with platelets.

Puccetti L, Pasqui AL, Bruni F, Pastorelli M, Ciani F, Palazzuoli A, Pontani A, Ghezzi A, Auteri A. · Department of Clinical Medicine and Immunology, Internal Medicine Division, Center for Atherosclerosis Research, Policlinico Le Scotte, University of Siena, V.le Bracci, 53100, Siena, Italy. · Int J Cardiol. · Pubmed #17050011 No free full text.

Abstract: BACKGROUND: Oxidized-LDL (ox-LDL) are involved in atherothrombosis by induction of endothelial dysfunction and thrombosis. The specific receptor lectin-like oxidized-LDL receptor-1 (LOX-1) is expressed in endothelial cells, monocytes and platelets. LOX-1 gene allelic variants (3'UTR/T) have been related with cardiovascular events and reduced anti-platelet activity induced by statins. OBJECTIVES: To detect whether LOX-1 polymorphisms could affect statins effectiveness in cardiovascular prevention. PATIENTS/METHODS: The present was a retrospective study performed in 751 white hypercholesterolemic subjects treated with increasing doses of atorvastatin (n=382, 247 male, 135 female) or simvastatin (n=369, 244 male, 125 female) up to 4 years, whose LDL target was 3.36 mmol/L according to the National Cholesterol Education Program, Adult Treatment Panel III (NCEP-ATPIII). Single nucleotide polymorphism were evaluated by allelic discrimination assays (PCR), lipid profile by enzymatic-colorimetric methods and C-reactive protein (CRP) by a nephelometric technique. RESULTS: Twenty-three non-ST elevation (NSTEMI) and eleven ST-elevation myocardial infarction (STEMI) were encountered in the observational period without differences between treatments (p=0.175) and sex (p=0.139). Each symptomatic subject (10 reaching the appropriate LDL target and 24 with still undesirable LDL) had the 3'UTR/T allelic variant (adjusted O.R. 4.63, 95% C.I. 3.46-6.70, p<0.0001). Among patients not reaching LDL target the C allele resulted protective with respect to T carriers (p<0.00001). Also, similar changes of CRP resulted in different event rate between T and C carriers (p<0.001) in the whole cohort. CONCLUSIONS: In the studied population LOX-1 genetic variants influence cardiovascular risk reduction induced by statins also in patients not reaching the LDL target. The previously described LOX-1-related antithrombotic actions of both statins employed could have a specific role in what observed, suggesting a genetic influence in statins LDL-lowering partially related actions.

Puccetti L, Pasqui AL, Pastorelli M, Ciani F, Palazzuoli A, Gioffrè W, Auteri A, Bruni F. · Department of Clinical Medicine and Immunological Sciences, Internal Medicine Division, Center for Atherosclerosis Research, University of Siena, Siena, Italy. · Atherosclerosis. · Pubmed #16285995 No free full text.

Abstract: Oxidized-low density lipoproteins (ox-LDL) and the specific receptor LOX-1 are involved in atherogenesis and atherothrombosis. LOX-1 downregulation is associated with the anti-platelet action of atorvastatin. 3'UTR/T LOX-1 polymorphism has been associated with increased risk of coronary artery disease. This study was planned to determine whether LOX-1 genetic variations could affect anti-platelet action of atorvastatin. We studied by platelet P-selectin (P-sel), CD36 and LOX-1 expression (cytofluorimetric detection) whether differences in cellular activation could be suitable in 109 3'UTR/T carriers out of 201 hypercholesterolemic subjects treated with atorvastatin 20mg/day. Hyperactivated platelets (P-sel in resting cells and % variation upon thrombin activation, p<0.001) were detected at baseline in patients without significant differences between T or C carriers. P-sel and platelet-associated ox-LDL, were significantly decreased (all p<0.001) in C carriers after one week of treatment before LDL reduction. In 3'UTR/T carriers P-sel was reduced (p<0.01) after 6 weeks of treatment according to LDL and ox-LDL reduction. In 3'UTR/T carriers atorvastatin reduced platelet activity by LDL and ox-LDL lowering and not by rapid CD36 and LOX-1 downregulation as in C carriers. Such data suggest that in T carriers LDL lowering is needed to achieve anti-platelet action.

Puccetti L, Sawamura T, Pasqui AL, Pastorelli M, Auteri A, Bruni F. · University of Siena, Siena, Italy. · Eur J Clin Invest. · Pubmed #15638819 No free full text.

Abstract: BACKGROUND: Oxidized-LDL (ox-LDL) are proatherogenic and platelet-activating molecules. Atorvastatin reduces platelet activity before cholesterol-lowering action. CD36 and lectin-like oxidized-LDL receptor-1 (LOX-1) are specific ox-LDL receptors expressed also in platelets. This study was planned to address whether the possible rapid effect of atorvastatin on platelets could be related to modulation of ox-LDL receptors. MATERIALS AND METHODS: Forty-eight hypercholesterolaemic subjects requiring statin treatment (atorvastatin 20 mg day(-1)) after an ineffective diet regimen were evaluated for complete lipid-profile (chromogenic); P-selectin (P-sel), CD36 and LOX-1 expression (cytofluorimetric detection); circulating and platelet-associated ox-LDL (ox- and Pox-LDL, ELISA); and intracellular citrullin recovery (iCit, HPLC) at baseline and 3, 6 and 9 days after inclusion in the study. Moreover, we studied 48 normal controls matched for sex and age. RESULTS: Platelet activity expressed by P-sel (in resting and thrombin-activated cells), CD36 and LOX-1 were increased in hypercholesterolaemic subjects (all P < 0.01). Atorvastatin induced a reduction of CD36 at 6 days (P < 0.05); and P-sel in resting (P < 0.001) and activated cells (P < 0.001) and LOX-1 were reduced at 9 days (all P < 0.001) in association with decreased Pox-LDL (P < 0.001) and increased iCit (P < 0.01). All data were obtained before a significant reduction of LDL and ox-LDL was achieved (P = 0.109 and 0.113). DISCUSSION: Present data suggest that platelet deactivation by atorvastatin is related to CD36 and LOX-1 expression reduction before significant LDL changes. Moreover, the modulation of LOX-1 can be considered a self-relevant antiatherothrombotic action of atoravastin owing to the important role of this receptor in the ox-LDL-mediated vascular damage.

Puccetti L, Bruni F, Pasqui AL, Pastorelli M, Bova G, Cercignani M, Palazzuoli A, Auteri A. · Department of Clinical Medicine and Immunological Sciences, Section of Medical Semeiotics, Center for Metabolic Diseases and Atherosclerosis, University of Siena, Siena, Italy. · Ital Heart J. · Pubmed #12478815 No free full text.

Abstract: BACKGROUND: The relation between fibrinolysis and cardiovascular disease is an open debate. Fibrinolysis is related to endothelial function and presents many molecular links with platelet and coagulation activity. Furthermore, reduced fibrinolysis has been reported in several dysmetabolic conditions. METHODS: To detect mechanisms linking dyslipidemias and fibrinolysis we evaluated 75 subjects (42 males, 33 females, 20 hypercholesterolemic, 20 hypertriglyceridemic or 20 with mixed hyperlipoproteinemia, 15 with isolated low HDL-cholesterol). Plasminogen activator inhibitor (PAI)-1, tissue-type plasminogen activator activity and plasmin-antiplasmin complexes (PAP) were determined at baseline and after the venous occlusion test. We also measured D-dimer, lipid pattern, soluble E-selectin, platelet surface P-selectin, prothrombin fragments 1 + 2 (F1 + 2), lipoprotein(a), factor VII, von Willebrand factor, plasma insulin, fibrinogen, homocysteine, thrombin activable fibrinolysis inhibitor (TAFI) activity, thrombomodulin, factor XIII, urokinase-type plasminogen activator. RESULTS: Hypertriglyceridemic patients were found to have lower PAP and D-dimer and higher PAI-1 serum levels (baseline and venous occlusion test, p < 0.001 and p < 0.01) compared to hypercholesterolemic and control subjects (p < 0.01, p < 0.001). P-selectin, F1 + 2 and TAFI were significantly increased only in hypercholesterolemic subjects (p < 0.001) and associated with reduced PAP and D-dimer, showing a linear relation with LDL-cholesterol levels (p < 0.01, r = -0.62 and p < 0.01, r = -0.59). PAI-1 activity was not different with respect to controls (baseline p = 0.59, venous occlusion test p = 0.42). Serum levels of von Willebrand factor were significantly increased in hypertriglyceridemic/low HDL subjects compared to hypercholesterolemics (p < 0.01). CONCLUSIONS: Impaired fibrinolysis in subjects with hypertriglyceridemia/low HDL-cholesterol is associated with increased serum levels of PAI-1 whereas enhanced thrombin generation and TAFI hyperactivity are the main findings in hypercholesterolemia. Such data may suggest the opportunity of evaluating several fibrinolytic factors when studied as prognostic factors in diverse dyslipidemias.

Puccetti L, Pasqui AL, Pastorelli M, Bova G, Cercignani M, Palazzuoli A, Auteri A, Bruni F. · Institute of Medical Semeiotics, Center for Metabolic Diseases and Atherosclerosis, University of Siena, Italy. · Int J Clin Pharmacol Res. · Pubmed #12067144 No free full text.

Abstract: To determine whether there is a correlation between fibrinolytic activity and dyslipidemia, we performed a study of 72 subjects (20 patients with hypercholesterolemia, 20 with hypertriglyceridemia, 12 with isolated low high-density lipoprotein (HDL)-cholesterol (mean age 47.7 +/- 6.3, body mass index 24.7 +/- 0.4) and 20 healthy controls. Plasminogen activator inhibitor-1 (PAI-1), tissue-plasminogen activator activity and plasmin-antiplasmin complexes (PAP) were detected at baseline and after venous occlusion test. We also measured at baseline lipidic pattern, soluble E and P selectins (sE-sel, sP-sel), prothrombin factor 1+2 (F1+2), lipoprotein(a), factor VII, plasma insulin, fibrinogen, homocysteine, and thrombin activable fibrinolysis inhibitor (TAFI) activity. Fibrinolysis was significantly reduced in hypertriglyceridemic patients compared with hypercholesterolemic patients and control subjects (PAP, p < 0.01 and p < 0.001) and was associated with increased PAI-1 (at baseline and after venous occlusion test, p < 0.001). sP-sel, F1 +2 and TAFI were not significantly different compared with controls, while hypercholesterolemic subjects showed a significant increase in these parameters (p < 0.001), which were related to decreased PAP only at the upper low-density lipoprotein (LDL)-cholesterol levels (>160 mg/dl) (p < 0.001, r = -0.76). Moreover, there was no significant difference in PAI-1 activity (at baseline and after venous occlusion test) compared with controls. In conclusion, endothelial dysfunction was the main mechanism of decreased fibrinolysis in subjects with hypertriglyceridemia and low HDL-cholesterol, while enhanced thrombin generation and TAFI activity were the main determinants in hypercholesterolemia.

Pasqui AL, Puccetti L, Bova G, Di Renzo M, Bruni F, Pastorelli M, Palazzuoli A, Auteri A. · Istituto di Semeiotica Medica, Università degli Studi di Siena, Policlinico Le Scotte, Italy. · Clin Exp Med. · Pubmed #12049187 No free full text.

Abstract: Inflammatory and lipid factors share an important role in atherosclerosis. Recent studies showed the concomitant presence and increase of complement components and lipids both in the atherosclerotic plaque and the circulating blood. The aim of this study was to examine the relationship between the complement system and lipid disorders. We evaluated the circulating complement terminal complex C5b-9, a clear sign of complement activation, in three groups of 30 patients the first with hypercholesterolemia, the second with hypertriglyceridemia (associated with low values of HDL-cholesterol), the third with low levels of HDL-cholesterol compared with an equivalent group of matched normolipemic subjects. We found a significant increase of sC5b-9 in each group of patients compared with controls. The mean sC5b-9 level in the hypercholesterolemic population was 366.2 +/- 141.2 ng/ml (P<0.01), 395.4 +/- 118.2 ng/ml in the hypertrygliceridemic group (P<0.01), 414.8 +/- 126.4 ng/ml in the low HDL-chol subjects (P<0.01), and 182.0 +/- 40.8. ng/ml in the control group. Regression analysis showed a significant direct correlation between sC5b-9 and triglycerides (r=0.64), and a significant inverse correlation between sC5b-9, HDL-chol (r=-0.74), and apo-A1 (r=-0.68); no significant relationship was found between sC5b-9 and cholesterol. We suggest that complement activation is associated with the various lipid disorders and is more important in those dyslipidemic conditions in which other factors may be involved. In particular, hypertriglyceridemia may be associated with endothelial and fibrinolytic disturbances, and the decrease of HDL may induce the failure of the regulatory proteins transported by the same HDL.

Puccetti L, Bruni F, Bova G, Cercignani M, Pompella G, Auteri A, Pasqui AL. · Institute of Medical Semeiotics, Centro per lo Studio delle Malattie Dismetaboliche e della Aterosclerosi, University of Siena, Italy. · Int J Clin Lab Res. · Pubmed #11196073 No free full text.

Abstract: Thrombosis is a complication of atherosclerosis and monocytes play a determinant role either in the progression of atherosclerotic plaque or in blood coagulation by way of tissue factor expression. Platelets play a direct role in thrombosis and a hyperfunctional state has been described in hypercholesterolemic subjects. Moreover, platelets seem to be able to enhance monocyte activity. Cholesterol-lowering molecules (statins) are reported to reduce cardiovascular risk, either by decreasing the circulating level of cholesterol or by non-lipidic actions such as the reduction of monocyte and platelet activity. The aim of our study was to investigate the influence of platelets on the expression of tissue factor by monocytes and the effect induced by cerivastatin. We measured tissue factor levels by ELISA and the procoagulant activity of stimulated monocytes by a clotting assay on cellular preparations and whole blood in 40 hypercholesterolemic subjects (22 male, 18 female, mean age 52.7 +/- 12 years, total cholesterol 251.6 +/- 19.9 mg/dl) before and after cerivastatin addition. Tissue factor expression was enhanced in hypercholesterolemic subjects compared with normal subjects (31.6 +/- 7.6 vs. 23 +/- 5.8 pg/cells, P < 0.01). The presence of platelets increased the amount of tissue factor (55.3 +/- 7.3 pg/cells, P < 0.001) and cerivastatin reduced the expression of tissue factor in isolated monocytes, in the mixed cellular system, and in whole blood (19.6 +/- 4.1 pg/cells, P < 0.001). In conclusion, tissue factor expression by monocytes is enhanced in hypercholesterolemic subjects compared with normal controls. Platelets enhance monocyte production of tissue factor, and cerivastatin is able to counteract this prothrombotic mechanism.

Pasqui AL, Bova G, Puccetti L, Bruni F, Pompella G, Auteri A. · Department of Internal Medicine and Immunology, University of Siena, Italy. · Nutr Metab Cardiovasc Dis. · Pubmed #11006922 No free full text.

Abstract: BACKGROUND AND AIM: Inflammatory and lipid factors share an important role in atherosclerosis. This study evaluates their relations in dyslipidemic subjects. METHODS AND RESULTS: We compared the complement system (serum hemolytic activity CH50, C3 and C4 fractions and terminal complex sC5b-9) in 30 hypercholesterolemic patients with elevated cholesterol and decreased HDL-cholesterol levels, 30 normolipemic patients with clinical atherosclerosis and 30 matched normal subjects. In addition we evaluated the circulating immune complexes containing cholesterol (chol-CIC) on the assumption that they might be important in complement activation, and the circulating levels of the adhesion molecule ICAM-1 (sICAM-1) as a sign of endhotelial dysfunction. We found a significant increase of sC5b-9 (but not of CH50 and C3, C4) in the hypercholesterolemics compared with the other groups. The plasma sC5b-9 level was inversely and significantly related to HDL-chol (regression analysis), whereas no direct significant relation was found between sC5b-9 and cholesterol. Chol-CIC were also significantly increased in this group. The atherosclerosis patients also presented a significant increase of sC5b-9. Lastly, both patient groups displayed a significant increase of sICAM-1. CONCLUSIONS: We suggest that complement activation in dyslipidemics may be induced by their increased immune complexes. However, the decrease of complement regulatory proteins carried by HDL is another important factor, while complement changes may be related to variations of other humoral and cell systems (endothelium, coagulative/fibrinolytic system), whose involvement is suggested in our study by the changes of sICAM-1.