Association of postalimentary lipemia with atherosclerotic manifestations

We identified different lipemic and metabolic responses after the ingestion of a standardized meal by healthy adults and related them to atherosclerotic markers. Samples from 60 normolipidemic adults were collected before and after a liquid meal (40 g fat/m² body surface) at 0, 2, 4, 6, and 8 h for measurements of lipids, free fatty acids (FFA), insulin, cholesteryl ester transfer protein (CETP), autoantibodies to epitopes of oxidized LDL (oxLDL Ab), lipolytic activities, and apolipoprotein E polymorphism. Mean carotid intima-media thickness (cIMT) was determined by Doppler ultrasound. The volunteers were classified into early (N = 39) and late (N = 31) triacylglycerol (TAG) responders to the test meal. Late responders showed lower HDL cholesterol concentration at fasting and in the TAG peak, lower insulin and higher FFA concentrations compared to early responders. Multivariate regression analyses showed that mean cIMT was associated with gender (male) and age in early responders and by cholesterol levels at the 6th hour in late responders. oxLDL Ab were explained by lipoprotein lipase and negatively by hepatic lipase and oxLDL Ab (fasting period) by CETP (negative) and FFA (positive). This study is the first to identify a postalimentary insulin resistance state, combined with a reduced CETP response exclusively among late responders, and the identification of the regulators of postalimentary atherogenicity. Further research is required to determine the metabolic mechanisms described in the different postalimentary phenotypes observed in this study, as well as in different pathological states, as currently investigated in our laboratory

Influence of alpha-tocopherol on the levels of serum anti-oxLDL antibodies

Purpose - This paper aims to evaluate the association between the a-tocopherol with the levels of serum anti-oxLDL autoantibodies and the risk markers for cardiovascular disease. Design/methodology/approach - A normolipidemic control group (n=30) and a hypercholesterolemic group (n=33) were used. Plasma lipid profile (colorimetric method), anti-oxLDL autoantibodies (ELISA) and a-tocopherol (HPLC) were analysed. Findings - The a-tocopherol (ß=-0.714; p=0.001) is negatively associated with anti-oxLDL autoantibodies in serum and with other risk markers for cardiovascular disease (BMI, WC, total cholesterol, LDL-c) and positively associated with HDL-c. Originality/value - Oxidized low density lipoprotein (oxLDL) and their autoantibodies are increased in subjects with hypercholesterolemia. The a-tocopherol can influence the levels of serum anti-oxLDL autoantibodiesFAPESPCNPqPRONU

Antibodies Against Oxldl and Acute Coronary Syndrome

Abstract Background: The oxidation of low-density lipoprotein (oxLDL) induces the formation of immunogenic epitopes in molecules. The presence of autoantibodies against oxLDL has been demonstrated in the serum of patients with coronary artery disease (CAD). However, the role of these autoantibodies in the pathophysiology of acute coronary syndromes (ACS) and their clinical significance remain undefined

Anticuerpos contra LDL-ox y síndrome coronario agudo

FUNDAMENTO: A oxidação da lipoproteína de baixa densidade (LDL-ox) induz à formação de epítopos imunogênicos na molécula. A presença de autoanticorpos contra a LDL-ox tem sido demonstrada no soro de pacientes com doença arterial coronariana (DAC). Contudo, o papel desses autoanticorpos na fisiopatologia das síndromes coronarianas agudas (SCA) e o seu significado clínico permanecem indefinidos. OBJETIVO: Avaliar a associação entre autoanticorpos contra a LDL-ox e SCA. MÉTODOS: Os títulos de imunoglobulina G autoanticorpos contra a LDL-ox por cobre (antiLDL-ox) e contra o peptídeo sintético D derivado da apolipoproteína B (antipeptD) foram determinados por ensaio imunoenzimático (ELISA) em 90 pacientes, nas primeiras 12h de SCA (casos) e em 90 pacientes com DAC crônica (controles). RESULTADOS: Os resultados mostraram que os títulos de antiLDL-ox foram significativamente mais elevados (p = 0,017) nos casos (0,40 ± 0,22), do que nos controles (0,33 ± 0,23). Por outro lado, os títulos de antipeptD foram significativamente menores (p < 0,01) nos casos (0,28 ± 0,23) do que nos controles (0,45 ± 0,30). A diferença dos títulos de ambos anticorpos entre os dois grupos estudados foi independente de idade, sexo, hipertensão arterial, diabete melito, dislipidemia, índice de massa corporal, tabagismo, perfil lipídico, uso de estatinas e história familiar de DAC. CONCLUSÃO: Os resultados mostraram que os títulos de antiLDL-ox foram significativamente mais elevados nos pacientes com síndrome coronariana aguda quando comparados aos pacientes com doença arterial coronariana e podem estar associados à instabilidade da placa aterosclerótica.BACKGROUND: The oxidation of low-density lipoprotein (oxLDL) induces the formation of immunogenic epitopes in molecules. The presence of autoantibodies against oxLDL has been demonstrated in the serum of patients with coronary artery disease (CAD). However, the role of these autoantibodies in the pathophysiology of acute coronary syndromes (ACS) and their clinical significance remain undefined. OBJECTIVE: To evaluate the association between antibodies against oxLDL and ACS. METHODS: Titers of IgG autoantibodies against oxLDL by copper (anti-oxLDL) and anti-D synthetic peptide derived from apolipoprotein B (antipeptD) were determined by Enzyme-linked immunosorbent assay (ELISA) in 90 patients, in the first 12 hours of ACS (cases) and in 90 patients with chronic CAD (controls). RESULTS: The results showed that the titers of anti-oxLDL were significantly higher (p = 0.017) in cases (0.40 ± 0.22) than in controls (0.33 ± 0.23). On the other hand, the titers of antipeptD were significantly lower (p < 0.01) in cases (0.28 ± 0.23) than in controls (0.45 ± 0.30). The difference in the titers of both antibodies between the two groups was independent of age, sex, hypertension, diabetes mellitus, dyslipidemia, body mass index, smoking, lipid profile, statin use and family history of CAD. CONCLUSION: The results showed that the titers of anti-oxLDL were significantly higher in patients with acute coronary syndrome as compared to patients with coronary artery disease and may be associated with atherosclerotic plaque instability.FUNDAMENTO: La oxidación de la lipoproteína de baja densidad (LDL-ox) induce a la formación de epítopos inmunogénicos en la molécula. La presencia de autoanticuerpos contra la LDL-ox ha sido demostrada en el suero de pacientes con enfermedad arterial coronaria (EAC). No obstante eso, el papel de esos autoanticuerpos en la fisiopatología de los síndromes coronarios agudos (SCA) y su significado clínico permanecen indefinidos. OBJETIVO: Evaluar la asociación entre autoanticuerpos contra la LDL-ox y SCA. MÉTODOS: Los títulos de inmunoglobulina G autoanticuerpos contra la LDL-ox por cobre (antiLDL-ox) y contra el péptido sintético D derivado de la apolipoproteína B (antipeptD) fueron determinados por ensayo inmunoenzimático (ELISA) en 90 pacientes, en las primeras 12h de SCA (casos) y en 90 pacientes con EAC crónica (controles). RESULTADOS: Los resultados mostraron que los títulos de antiLDL-ox fueron significativamente más elevados (p =0,017) en los casos (0,40 ± 0,22), que en los controles (0,33 ± 0,23). Por otro lado, los títulos de antipeptD fueron significativamente menores (p < 0,01) en los casos (0,28 ± 0,23) que en los controles (0,45 ± 0,30). La diferencia de los títulos de ambos anticuerpos entre los dos grupos estudiados fue independiente de edad, sexo, hipertensión arterial, diabetes mellitus, dislipidemia, índice de masa corporal, tabaquismo, perfil lipídico, uso de estatinas e historia familiar de EAC. CONCLUSIÓN: Los resultados mostraron que los títulos de antiLDL-ox fueron significativamente más elevados en los pacientes con síndrome coronario agudo cuando fueron comparados a los pacientes con enfermedad arterial coronaria y pueden estar asociados a inestabilidad de la placa aterosclerótica

Anticorpos contra LDL-ox e síndrome coronariana aguda Anticuerpos contra LDL-ox y síndrome coronario agudo Antibodies against OxLDL and acute coronary syndrome

FUNDAMENTO: A oxidação da lipoproteína de baixa densidade (LDL-ox) induz à formação de epítopos imunogênicos na molécula. A presença de autoanticorpos contra a LDL-ox tem sido demonstrada no soro de pacientes com doença arterial coronariana (DAC). Contudo, o papel desses autoanticorpos na fisiopatologia das síndromes coronarianas agudas (SCA) e o seu significado clínico permanecem indefinidos. OBJETIVO: Avaliar a associação entre autoanticorpos contra a LDL-ox e SCA. MÉTODOS: Os títulos de imunoglobulina G autoanticorpos contra a LDL-ox por cobre (antiLDL-ox) e contra o peptídeo sintético D derivado da apolipoproteína B (antipeptD) foram determinados por ensaio imunoenzimático (ELISA) em 90 pacientes, nas primeiras 12h de SCA (casos) e em 90 pacientes com DAC crônica (controles). RESULTADOS: Os resultados mostraram que os títulos de antiLDL-ox foram significativamente mais elevados (p = 0,017) nos casos (0,40 ± 0,22), do que nos controles (0,33 ± 0,23). Por outro lado, os títulos de antipeptD foram significativamente menores (p FUNDAMENTO: La oxidación de la lipoproteína de baja densidad (LDL-ox) induce a la formación de epítopos inmunogénicos en la molécula. La presencia de autoanticuerpos contra la LDL-ox ha sido demostrada en el suero de pacientes con enfermedad arterial coronaria (EAC). No obstante eso, el papel de esos autoanticuerpos en la fisiopatología de los síndromes coronarios agudos (SCA) y su significado clínico permanecen indefinidos. OBJETIVO: Evaluar la asociación entre autoanticuerpos contra la LDL-ox y SCA. MÉTODOS: Los títulos de inmunoglobulina G autoanticuerpos contra la LDL-ox por cobre (antiLDL-ox) y contra el péptido sintético D derivado de la apolipoproteína B (antipeptD) fueron determinados por ensayo inmunoenzimático (ELISA) en 90 pacientes, en las primeras 12h de SCA (casos) y en 90 pacientes con EAC crónica (controles). RESULTADOS: Los resultados mostraron que los títulos de antiLDL-ox fueron significativamente más elevados (p =0,017) en los casos (0,40 ± 0,22), que en los controles (0,33 ± 0,23). Por otro lado, los títulos de antipeptD fueron significativamente menores (p BACKGROUND: The oxidation of low-density lipoprotein (oxLDL) induces the formation of immunogenic epitopes in molecules. The presence of autoantibodies against oxLDL has been demonstrated in the serum of patients with coronary artery disease (CAD). However, the role of these autoantibodies in the pathophysiology of acute coronary syndromes (ACS) and their clinical significance remain undefined. OBJECTIVE: To evaluate the association between antibodies against oxLDL and ACS. METHODS: Titers of IgG autoantibodies against oxLDL by copper (anti-oxLDL) and anti-D synthetic peptide derived from apolipoprotein B (antipeptD) were determined by Enzyme-linked immunosorbent assay (ELISA) in 90 patients, in the first 12 hours of ACS (cases) and in 90 patients with chronic CAD (controls). RESULTS: The results showed that the titers of anti-oxLDL were significantly higher (p = 0.017) in cases (0.40 ± 0.22) than in controls (0.33 ± 0.23). On the other hand, the titers of antipeptD were significantly lower (p < 0.01) in cases (0.28 ± 0.23) than in controls (0.45 ± 0.30). The difference in the titers of both antibodies between the two groups was independent of age, sex, hypertension, diabetes mellitus, dyslipidemia, body mass index, smoking, lipid profile, statin use and family history of CAD. CONCLUSION: The results showed that the titers of anti-oxLDL were significantly higher in patients with acute coronary syndrome as compared to patients with coronary artery disease and may be associated with atherosclerotic plaque instability

Analytical quantification of low-density lipoprotein using europium tetracycline indicator

Low-density lipoprotein (LDL) is known as `bad` cholesterol. If too much LDL circulates in the blood it can be retained in the walls of the arteries, causing atherosclerosis. In this paper we showed an alternative method to quantify LDL using the europium tetracycline (EuTc) indicator. The optical properties of the EuTc complex were investigated in aqueous solutions containing LDL. An enhancement was observed of the europium luminescence in the solutions with LDL compared those without the lipoprotein. A method to quantify the amount of LDL in a sample, based on EuTc enhanced luminescence, is proposed. The enhancement mechanism is also discussed. Copyright (C) 2009 John Wiley & Sons, Ltd.FAPESPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPqConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)IMFCx (Instituto do Milenio de Fluidos Complexos)IMFCx (Instituto do Milenio de Fluidos Complexos

Enhancement on the Europium emission band of Europium chlortetracycline complex in the presence of LDL

Low-density lipoprotein (LDL) particles are the major cholesterol-carrying lipoprotein in the human circulation from the liver to peripheral tissues. High levels of LDL-Cholesterol (LDL-C) are known risk factor for the development of coronary artery disease (CAD). The most common approach to determine the LDLC in the clinical laboratory involves the Friedewald formula. However, in certain situations, this approach is inadequate. In this paper we report on the enhancement on the Europium emission band of Europium chlortetracycline complex (CTEu) in the presence of LDL. The emission intensity at 615 nm of the CTEu increases with increasing amounts of LDL. This phenomenon allowed us to propose a method to determine the LDL concentration in a sample composed by an aqueous solution of LDL. With this result we obtained LDL calibration curve, LOD (limit of detection) of 0.49 mg/mL and SD (standard deviation) of 0.003. We observed that CTEu complex provides a wider dynamic concentration-range for LDL determination than that from Eu-tetracycline previously. The averaged emission lifetimes of the CTEu and CTEu with LDL (1.5 mg/mL) complexes were measured as 15 and 46 Its, respectively. Study with some metallic interferents is presented. (C) 2010 Elsevier Inc. All rights reserved.State of Sao Paulo Research Foundation (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)National institute of Science and Technology of Complex Fluids (INCT-FCx)National institute of Science and Technology of Complex Fluids (INCT-FCx)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)National Counsel of Technological and Scientific Development (CNPq

Investigation of the Europium Emission Spectra of the Europium-Oxytetracycline Complex in the Presence of Human Low-Density Lipoproteins

Low-Density Lipoprotein (LDL), often known as ""bad cholesterol"" is one of the responsible to increase the risk of coronary arterial diseases. For this reason, the cholesterol present in the LDL particle has become one of the main parameters to be quantified in routine clinical diagnosis. A number of tools are available to assess LDL particles and estimate the cholesterol concentration in the blood. The most common methods to quantify the LDL in the plasma are the density gradient ultracentrifugation and nuclear magnetic resonance (NMR). However, these techniques require special equipments and can take a long time to provide the results. In this paper, we report on the increase of the Europium emission in Europium-oxytetracycline complex aqueous solutions in the presence of LDL. This increase is proportional to the LDL concentration in the solution. This phenomenum can be used to develop a method to quantify the number of LDL particles in a sample. A comparison between the performances of the oxytetracycline and the tetracycline in the complexes is also made.CNPqConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESPINCT-FCx (Instituto Nacional de Ciencias e Tecnologia de Fluidos Complexos)INCT-FCx (Instituto Nacional de Ciencias e Tecnologia de Fluidos Complexos

Early Increase in Autoantibodies Against Human Oxidized Low-Density Lipoprotein in Hypertensive Patients After Blood Pressure Control

BACKGROUND Oxidized lipoproteins and antioxidized low-density lipoprotein (anti-oxLDL) antibodies (Abs) have been detected in plasma in response to blood pressure (BP) elevation, suggesting the participation of the adaptive immune system. Therefore, treatment of hypertension may act on the immune response by decreasing oxidation stimuli. However, this issue has not been addressed. Thus, we have here analyzed anti-oxLDL Abs in untreated (naive) hypertensive patients shortly after initiation of anti hypertensive therapeutic regimens. METHODS Titers of anti-oxLDL Abs were measured in subjects with recently diagnosed hypertension on stage 1 (n = 94), in primary prevention of coronary disease, with no other risk factors, and naive of anti hypertensive medication at entry. Subjects were randomly assigned to receive perindopril, hydrochlorothiazide (HCTZ), or indapamide (INDA) for 12 weeks, with additional perindopril if necessary to achieve BP control. Abs against copper-oxidized LDL were measured by enzyme-linked immunosorbent assay. RESULTS Twelve-week antihypertensive treatment reduced both office-based and 24-h ambulatory BP measurements (P < 0.0005). The decrease in BP was accompanied by reduction in thiobarbituric acid-reactive substances (TBARS) (P < 0.05), increase in anti-oxLDL Ab titers (P < 0.005), and improvement in flow-mediated dilation (FMD) (P < 0.0005), independently of treatment. Although BP was reduced, we observed favorable changes in anti-oxLDL titers and FMD. CONCLUSIONS We observed that anti-oxLDL Ab titers increase after antihypertensive therapy in primary prevention when achieving BP targets. Our results are in agreement with the concept that propensity to oxidation is increased by essential hypertension and anti-oxLDL Abs may be protective and potential biomarkers for the follow-up of hypertension treatment.FAPESP (The State of Sao Paulo Research Foundation)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The National Institute of Science and Technology of Complex Fluids (INCT-FCx)The National Institute of Science and Technology of Complex Fluids (INCT-FCx)The National Institute of Science and Technology-Nanomaterials for Integrated Markers (INCT-IINAMI)The National Institute of Science and Technology-Nanomaterials for Integrated Markers (INCT-IINAMI)CAPES (National Counsel of Technological and Scientific Development)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES