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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Aterosclerose na artrite reumatóide e sua associação com auto-imunidade humoral / Atherosclerosis in rheumatoid arthritis and its relationship with humoral autoimmunity

Pereira, Ivânio Alves 28 February 2007 (has links)
Objetivos: Muitas questões permanecem sobre as causas da aterosclerose acelerada nos pacientes com doenças inflamatórias sistêmicas como a artrite reumatóide (AR). Estudos na população geral sugeriram que além da inflamação existe uma participação patogênica da auto-imunidade na aterosclerose e discutem a possível associação dos anticorpos contra fosfolípides e proteínas de choque térmico (Hsp). O objetivo deste estudo foi investigar a presença de anticorpos contra fosfolípides, beta2-glicoproteína 1 (beta2-gp1), lipoproteína lipase (LPL) e Hsp em pacientes com AR e avaliar a associação entre estes anticorpos com a presença de aterosclerose subclínica de carótidas. Métodos: Anticorpos contra cardiolipina (aCL) IgG e IgM, beta2-gp1 IgG, IgM e IgA , Hsp 60 e Hsp 65 foram testados por ELISA em um grupo de 71 pacientes com AR comparado com 53 indívíduos controles não portadores de AR, de idade e sexo similar. Foram excluídos os pacientes com HAS, diabetes melitos e os fumantes em ambos os grupos. Níveis de lipoproteínas, parâmetros clínicos da AR, questionário de avaliação de saúde (HAQ), escore de atividade da doença (DAS) 28, velocidade de hemossedimentação (VHS) e proteína C reativa (PCR) foram avaliadas. A associação entre a presença dos anticorpos aCL, beta2-gp1, Hsp 60 e Hsp 65 com os parâmetros clínicos de atividade da doença, com a presença das placas de aterosclerose e com a medida da espessura íntimomedial (IMT) da carótida comum, usando ultra-som (US) modo B de alta resolução foram pesquisadas. Resultados: A idade média no grupo com AR foi 48,93 ± 12,31 vs. 45,37 ± 9,37 no grupo controle saudável (p = 0,20); 90,1% no grupo com AR eram do sexo feminino vs. 86,8% no grupo controle (p = 0,56); índice de massa corporal (IMC) foi 25,72 ± 4,57kg/m² no grupo com AR vs. 26,40 ± 4,52kg/m² no grupo controle (p = 0, 69); Os níveis de colesterol, LDL, triglicerídeos e a relação CT/HDL não foram diferentes quando comparamos os 2 grupos (p > 0,05). O nível de HDL foi maior no grupo com AR vs. grupo controle com 60,56 ± 14,40mg/dl e 54,52 ± 11,55 respectivamente (p = 0,05). A média da medida da IMT foi 0,721 ± 0,16 mm na AR e 0,667 ± 0,14mm no grupo controle, e a IMT dos pacientes com AR foi maior naqueles com idade acima dos 50 anos (P < 0,001). No grupo com AR, 14,1% dos pacientes tinham placas nas carótidas vs. 1,9% dos indivíduos saudáveis (p = 0,02) e no grupo com AR, as placas foram mais frequentes nos pacientes acima dos 50 anos (p = 0,004). No grupo AR, 5,6% tinham anticorpos aCL IgG vs. 3,8% no grupo controle (p > 0,05); 14,1% apresentavam aCL IgM vs. 7,5% (p > 0,05); 43,7% tinham anti-beta2-gp1 IgA vs. 40,8% no grupo controle (p > 0,05). A prevalência de anti-beta2-gp1 IgG e IgM e anti-LPL não foi diferente entre os pacientes com AR e o grupo controle ( p > 0,05). A presença dos anticorpos anti-Hsp 60 e 65 na AR e no grupo controle não foram diferentes (p > 0,05), mas os títulos de anticorpos contra Hsp 65 e beta2-gp1 IgM foram maiores no grupo com AR ( p = 0,007 e p = 0,03 respectivamente). Nós não encontramos associação entre a presença e os títulos dos anticorpos aCL IgG e IgM, beta2-gp1 IgG, IgM e IgA, LPL e Hsp 60 e 65 com a presença de placas nas carótidas ou com a medida da IMT (p > 0,05). Discussão: Este estudo confirma achados anteriores da maior prevalência de aterosclerose carotídea nos pacientes com AR e sua correlação com idade, colesterol e LDL. Embora tenha se encontrado uma tendência a maior presença de anticorpos nos pacientes com AR, não houve relação entre a presença da aterosclerose mais prevalente nos pacientes com AR, com a auto-imunidade dirigida contra cardiolipina, beta2-gp1 ou Hsp. / Purpose: Many questions remain unanswered about the causes of accelerated atherosclerosis in patients with inflammatory systemic diseases such as rheumatoid arthritis (RA). Some studies have suggested the role of autoimmunity besides inflammation in the pathogenesis of atherosclerosis in general population and have also discussed the possible association with antibodies directed to phospholipids and heat shock proteins (Hsp). The aim of this study was to investigate the presence of antibodies against phospholipids, beta2-glycoprotein1 (beta2-gp1), lipoprotein lipase (LPL) and Hsp in RA subjects and evaluate the association between these antibodies with the presence of subclinical carotid atherosclerosis. Methods: Tests to antibodies against cardiolipin (aCL) IgG and IgM, beta2-gp1 IgG, IgM and IgA ,Hsp 60 and Hsp 65 were done by ELISA test in a group of 71 RA subjects compared with 53 age and sex-matched non-RA subjects. Smoking, diabetic and hypertensive patients were excluded in both groups. The lipoprotein levels, clinical parameters of RA, Health Assessment Questionnaire (HAQ), Disease Activity Score (DAS) 28, Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) were evaluated. The association between the presence of antibodies against cardiolipin, beta2-gp1 and Hsp 60 and 65 with the clinical parameters of disease activity in RA, and with the presence of plaques and mean intimo-medial thickness (IMT) of common carotid using high-resolution B-mode ultrasound were assessed. Results: Mean age in RA group was 48.93 ± 12.31 vs. 45.37 ± 9.37 in healthy control group (p = 0.20); 90.1% were women in RA group vs. 86.8% in healthy control (p = 0.56); body mass index (BMI) were 25.72 ± 4.57 in RA group vs. 26.40 ± 4.52 in healthy control (p = 0.69). The levels of cholesterol, LDL, triglycerides, CT/HDL didn t have difference between the two groups (p > 0.05). The HDL was higher in RA group vs. control group with 60.56 ± 14.40mg/dl and 54.52 ± 11.55 respectively (p = 0.05). The mean IMT was 0.721 ± 0.16mm in RA and 0.667 ± 0.14mm in control group, and the IMT was higher in patients older than 50 years among RA subjects (p < 0.001). In RA subjects, 14.1% had carotid plaques vs. 1.9% in healthy controls (p = 0.02). In RA group, the carotid plaques were more frequent in patients older than 50 years (p = 0.004). In RA group, 5.6% had antibodies against cardiolipin IgG vs. 3.8% in control group (p > 0.05); 14.1% in RA group had anti-cardiolipin IgM vs. 7.5% (p > 0.05); 43.7% had anti-beta2-gp1 IgA vs 40.8% in control group (p > 0.05). The presence of anti-beta2-gp1 IgG and IgM, and anti-LPL didn t have significant difference between the groups (p > 0.05). The prevalence of antibodies to Hsp 60 and Hsp 65 were similar in RA and in control group (p > 0.05), but the titers of antibodies against Hsp 65 and beta2-gp1 IgM were higher in RA group (p = 0.007 and p = 0.03 respectively). We didn t find relationship between antibodies against cardiolipin IgG and IgM, or beta2-gp1 IgG, IgM and IgA, LPL, Hsp 60 and 65 with mean IMT or plaque carotid (p > 0.05). Discussion: This study confirms the great prevalence of carotid atherosclerosis in RA subjects and its correlation with age, cholesterol and LDL. Although it was found a tendency to have more autoantibodies in RA subjects, there weren t any link between atherosclerosis in RA with autoimmunity against cardiolipin, beta2-gp 1, LPL or Hsp.
352

Biomarcadores de risco cardiovascular em pacientes HIV positivos tratados e não tratados com terapia antirretroviral / Biomarkers of cardiovascular risk in HIV-positive patients treated and untreated with antiretroviral therapy.

Cicarelli, Luciane Marzzullo 30 September 2016 (has links)
No advento dos antirretrovirais potentes, os indivíduos infectados pelo vírus da imunodeficiência humana (HIV) começaram a apresentar risco maior para o desenvolvimento de doença cardiovascular (DCV). Este aumento do risco cardiovascular pode ser associado tanto à infecção viral quanto ao tratamento antirretroviral (TARV), que provocam mudanças pró-aterogênicas como o aumento do colesterol total e da lipoproteína de baixa densidade (LDL), além da diminuição da lipoproteína de alta densidade (HDL). A ativação imune e as alterações lipídicas são mecanismos associados com a infecção pelo HIV e com o risco de DCV. Este trabalho utilizou ensaios imunoenzimáticos para a determinação plasmática de biomarcadores emergentes de risco cardiovascular relacionados com modificações da lipoproteína de baixa densidade, a saber: LDL eletronegativa [LDL(-)] e formas oxidadas da LDL, ou seja, LDL-oxi (resíduos lisina da apolipoproteína B100 modificados com malondialdeído), LDL-HNE (resíduos lisina da ApoB100 modificados com 4-hidroxinonenal) e LDL-CML (resíduos lisina da ApoB100 modificados por carboximetila), além de biomarcadores relacionados com a resposta imune-inflamatória, ou seja, autoanticorpos IgG e IgM anti-LDL(-), imunocomplexo de LDL(-) [IC-LDL(-)], proteína amiloide sérica A (SAA) e mieloperoxidase (MPO). Também foram determinadas as concentrações séricas dos biomarcadores de risco relacionados às apolipoproteínas: apolipoproteína A-I (ApoA-I), apolipoproteína B (ApoB) e apolipoproteína E (ApoE). A população estudada incluiu indivíduos com infecção pelo HIV, tratados (HIV-TARV) e não tratados (HIV-NT) com terapia antirretroviral e indivíduos sem infecção pelo HIV (controle). Não foram identificadas diferenças para as concentrações de LDL(-), IC-LDL(-), anti- LDL(-)-IgM, SAA, ApoA-I, ApoB e ApoE entre os grupos estudados (HIV-TARV, HIV-NT e controle). A ApoA-I correlacionou-se positivamente com ApoB e ApoE (rs= 0,418 e rs= 0,347, Spearman, p<0,01) e a ApoB com a ApoE (rs= 0,286, Spearman, p<0,01). Verificou-se correlação inversa entre as concentrações de LDL(-) e IC-LDL(-) (rs= -0,214, Spearman, p<0,05). Os níveis de anti-LDL(-)-IgG correlacionaram-se positivamente com IC-LDL(-) e anti-LDL(-)-IgM (rs= 0,240, Spearman, p<0,05 e rs= 0,348, Spearman, p<0,01). As concentrações de LDL-CML correlacionaram-se positivamente com LDL(-), LDL-oxi, LDL-HNE e IC-LDL(-) (rs= 0,212, Spearman, p<0,05; rs= 0,214, Spearman, p<0,05; rs= 0,573, Spearman, p<0,01 e rs= 0,219, Spearman, p<0,05). O grupo HIV-NT apresentou níveis mais elevados de anticorpos anti-LDL(-)-IgG comparado ao grupo controle (Kruskal-Wallis, p<0,01). Em contraste, observou-se no grupo HIV-NT diminuição das concentrações de MPO, LDL-HNE e LDL-CML em relação ao grupo controle (Kruskal-Wallis, p<0,01). A comparação dos grupos HIV-NT e HIV-TARV demonstrou que o TARV promoveu diminuição das concentrações dos anticorpos anti-LDL(-)-IgG e aumentou os níveis de LDL-oxi (Kruskal-Wallis, p<0,01). O grupo HIV-TARV apresentou aumento das concentrações de LDL-oxi e diminuição dos níveis de MPO, LDL-HNE e LDL-CML em relação ao controle (Kruskal-Wallis, p<0,01). Em conclusão, a infecção pelo HIV modificou o biomarcador de inflamação MPO e o perfil de biomarcadores relacionados às modificações da LDL (menor formação de LDL-HNE e LDL-CML), além aumentar a resposta imune-humoral à LDL eletronegativa [anti-LDL(-)-IgG], enquanto o tratamento com antirretrovirais inibiu esta resposta. Os outros biomarcadores estudados não foram modificados pela infecção viral ou pelo tratamento antirretroviral. / In the advent of potent antiretroviral therapy, individuals infected with human immunodeficiency virus (HIV) have showed an increased risk for developing cardiovascular disease (DCV). Studies have discussed that the increased risk may be related to both the disease and antiretroviral treatment (TARV), that produced pro-atherogenic changes such as increased of total cholesterol and low density lipoprotein (LDL) and decreased high density lipoprotein. The immune activation and the lipid modifications are well known mechanisms related to HIV infection and the risk of DCV. This study used immunoassays for plasma quantification for emerging biomarkers of cardiovascular risk related to modification of low density lipoprotein: electronegative LDL [LDL(-)] and oxidized forms of LDL, LDL-oxi (lysine residues of apolipoprotein B100 modified by malondialdehyde), LDL-HNE (lysine residues of ApoB100 modified by 4-hydroxynonenal) and LDL-CML (lysine residues of ApoB100 modified by carboxymethyl) and biomarkers associated to immune and inflammatory responses, IgG and IgM autoantibodies anti-LDL(-) and immunecomplexe of LDL(-) [IC-LDL(-)], serum amyloid A protein (SAA) and myeloperoxidase (MPO). Also, were determined serum concentrations of risk biomarkers related to apolipoproteins: apolipoprotein A-I (ApoA-I), apolipoprotein B (ApoB) and apolipoprotein E (ApoE). The studied population included patients with HIV infection, treated (HIV-TARV) and untreated (HIV-NT) with antiretroviral therapy and individuals without HIV infection (controle). No differences were identified for concentrations of LDL(-), ICLDL(-), anti-LDL(-)-IgM, SAA, ApoA-I, ApoB and ApoE between studied groups (HIV-TARV, HIV-NT and controle). The ApoA-I was positively correlated to ApoB and ApoE (rs= 0,418 e rs= 0,347, Spearman, p<0,01) and ApoB to ApoE (rs= 0,286, Spearman, p<0,01). There was an inverted correlation between LDL(-) and IC-LDL(-) (rs= -0.214, Spearman, p<0,05). The levels of anti-LDL(-)-IgG were positively correlated to IC-LDL(-) and antibodies anti-LDL(-)-IgM (rs= 0.240; Spearman; p <0.05 and rs= 0.348; Spearman; p <0.01). The concentrations of LDL-CML were positively correlated to LDL(-), LDL-oxi, LDL-HNE e IC-LDL(-) (rs= 0,212, Spearman, p<0,05; rs= 0,214, Spearman, p<0,05; rs= 0,573, Spearman, p<0,01 e rs= 0,219, Spearman, p<0,05). The HIV-NT group showed higher levels of anti-LDL(-)-IgG compared to Control group (Kruskal-Wallis, p<0,01). In contrast, was observed lower levels for HIV-NT group to MPO, LDL-HNE and LDL-CML when compared to Control group (Kruskal-Wallis, p<0,01). The comparison of HIV-NT and HIV-TARV groups demonstrated that TARV caused a decrease of concentrations of anti-LDL(-)-IgG antibodies and an increased of LDL-oxi levels (Kruskal-Wallis, p <0.01). The HIV-TARV group showed increased LDL-oxi concentrations and decreased at levels of MPO, LDL-HNE e LDL-CML when compared to Control (Kruskal-Wallis, p<0,01). In conclusion, the HIV infection changed the biomarker of inflammation MPO and the profile of biomarkers related to modifications of LDL (lower concentrations of LDL-HNE and LDL-CML), as well as increased the humoral-immune response to electronegative LDL [anti-LDL(-)-IgG], while treatment with antiretroviral therapy inhibited this response. The other studied biomarkers were not modified either by viral infection or antiretroviral treatment.
353

Efeitos do LDL oxidado em macrófagos M2. Implicações na aterosclerose. / Effects of oxidized LDL in M2 macrophages. Implications in atherosclerosis

Fernanda Magalhães Gonçalves 12 September 2017 (has links)
A aterosclerose é uma doença crônica onde duas características marcantes são observadas: retenção de lipídios e inflamação. Compreender as interações entre as células do sistema imunológico e as lipoproteínas envolvidas na aterogênese são desafios urgentes, uma vez que as doenças cardiovasculares são a principal causa de morte no mundo. Os macrófagos são cruciais para o desenvolvimento de placas ateroscleróticas e para a perpetuação da inflamação em tais lesões; estas células também estão diretamente envolvidas na ruptura de placa instável. Recentemente diferentes populações de macrófagos estão sendo identificadas nas lesões ateroscleróticas. Embora macrófagos M2 tenham sido identificados, a função destas células na aterosclerose ainda não está definida. Neste projeto, avaliamos se a adição de LDLox altera a função de macrófagos M2. Resultados: 1- Foi possível observar que os M2 se mantem viáveis após o estímulo com as lipoproteínas. 2- Quando avaliamos a expressão de moléculas co-estimulatórias, receptores Scavenger, lectinas e integrinas na superfície das células, observamos que a adição de LDLn ou LDLox em 2 concentrações diferentes (5 e 50ug/ml), por diferentes períodos de tempo não alterou a expressão de nenhum dos marcadores avaliados. A presença de LDL também não alterou outra função primordial dos M2, a capacidade de fagocitose. 3- Quando investigamos a presença de citocinas no sobrenadante das culturas estimuladas ou não com as lipoproteínas, identificamos um aumento na secreção de IL-8, uma citocina pró-inflamatória, na presença de LDLox, semelhante ao observado com a população de macrófagos M1. 4- Avaliamos se os macrófagos M2 estimulados ou não com LDL mantem sua capacidade de favorecer a angiogênese. Observamos que nas culturas estimuladas com o sobrenadante das culturas dos M2 mantidos na presença de LDLox houve uma inibição significativa da formação de túbulos pelas HUVECs. 5- Observamos que na presença do meio condicionado dos M2 estimulados com LDLox ocorreu uma intensa degradação dos filamentos de matriz extracelular produzida por MEFs. 6- Avaliamos a expressão gênica de componentes de matriz, membrana basal, moléculas de adesão, proteases e também inibidores de protease nestas células. Dos 96 genes avaliados, observamos que a adição de LDLox reduziu a expressão de 10 genes de maneira significativa, entre eles: beta-Actina (ACTB), Colágeno 6A2 (Col6A2), Integrina alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), molécula de adesão celular endotelial plaquetária (PECAM) e Inibidor de metalopeptidase 2 (TIMP2). A adição de LDLox aumentou significativamente somente a expressão de trombospondina (TSP1). A adição de LDLn não alterou a expressão de nenhum gene de forma significativa. 7- A adição de LDLox induziu aumento da expressão da TSP1 e redução da expressão de colágeno 6, quando comparadas aos macrófagos M2 sem estímulo. Nossos resultados indicam que a adição de LDLox altera diversas funções dos macrófagos M2 in vitro. Em especial detectamos uma inibição significativa na angiogênese e também a secreção de mediadores que induzem a degradação da matriz extracelular. A adição de LDLox também inibiu a expressão de genes envolvidos com a estabilização da matriz extracelular. Nossos resultados sugerem que esta população de células pode contribuir para a perpetuação do processo inflamatório e degradação tecidual observados na lesão dos pacientes. Assim, acreditamos que este projeto contribuiu para o esclarecimento da participação dos M2 na patologia da aterosclerose / Atherosclerosis is a chronic disease where two key characteristics are observed: lipid retention and inflammation. Understanding the interactions between the cells of the immune system and the lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death in the world. Macrophages are crucial for the development of atherosclerotic plaques and for the inflammation in such lesions; These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although M2 macrophages has been identified, the function of these cells in atherosclerosis has not yet been defined. This project, we evaluated whether the addition of OxLDL alters the function of M2 macrophages. Results: 1- M2 macrophages remain viable after stimulation with the lipoproteins. 2- When evaluated the expression of co-stimulatory molecules, Scavenger receptors, lectins and integrins on the surface of the cells. We observed that the addition of LDLn or OxLDL at 2 different concentrations (5 and 50 ?g / ml) for different time periods did not alter the expression of any of the evaluated markers. 3- The presence of LDL also did not alter other primordial function of M2 cells, phagocytosis. 4- Was observed that cultures stimulated with conditioned medium of OxLDL-stimulated M2 there was a significant inhibition of tubule formation by HUVECs. 5- We observed that in the presence of OxLDL-stimulated M2 cells conditioned médium an intense degradation of the matrix filaments occurred. 6- We evaluated the gene expression of matrix components, basement membrane, adhesion molecules, proteases and also protease inhibitors in these cells. Of the 96 evaluated genes, we observed that the addition of OxLDL significantly reduced the expression of 10 genes, among them: Actin-beta (ACTB), Collagen 6A2 (Col6A2), Integrin alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), Platelet endothelial cell adhesion molecule (PECAM) and metallopeptidase 2 inhibitor (TIMP2). The addition of OxLDL significantly increased only the expression, thrombospondin-1 (TSP1). Addition of LDLn did not significantly alter the expression of any gene. 7- That OxLDL addition induced increased TSP1 expression and reduced collagen 6 expression, when compared to M2 macrophages without stimulation. Our results indicate that the addition of OxLDL alters several M2 macrophages functions in vitro. In particular we detected a significant inhibition in angiogenesis and also the secretion of mediators that induce the degradation of the extracellular matrix. The addition of OxLDL also inhibited the expression of genes involved in extracellular matrix stabilization. Our results suggest that this cell population may contribute to the perpetuation of the inflammatory process and tissue degradation observed in the lesion of the patients. Thus, we believe that this project contributed to better understand the participation of M2 in the pathology of atherosclerosis
354

Aterosclerose na artrite reumatóide e sua associação com auto-imunidade humoral / Atherosclerosis in rheumatoid arthritis and its relationship with humoral autoimmunity

Ivânio Alves Pereira 28 February 2007 (has links)
Objetivos: Muitas questões permanecem sobre as causas da aterosclerose acelerada nos pacientes com doenças inflamatórias sistêmicas como a artrite reumatóide (AR). Estudos na população geral sugeriram que além da inflamação existe uma participação patogênica da auto-imunidade na aterosclerose e discutem a possível associação dos anticorpos contra fosfolípides e proteínas de choque térmico (Hsp). O objetivo deste estudo foi investigar a presença de anticorpos contra fosfolípides, beta2-glicoproteína 1 (beta2-gp1), lipoproteína lipase (LPL) e Hsp em pacientes com AR e avaliar a associação entre estes anticorpos com a presença de aterosclerose subclínica de carótidas. Métodos: Anticorpos contra cardiolipina (aCL) IgG e IgM, beta2-gp1 IgG, IgM e IgA , Hsp 60 e Hsp 65 foram testados por ELISA em um grupo de 71 pacientes com AR comparado com 53 indívíduos controles não portadores de AR, de idade e sexo similar. Foram excluídos os pacientes com HAS, diabetes melitos e os fumantes em ambos os grupos. Níveis de lipoproteínas, parâmetros clínicos da AR, questionário de avaliação de saúde (HAQ), escore de atividade da doença (DAS) 28, velocidade de hemossedimentação (VHS) e proteína C reativa (PCR) foram avaliadas. A associação entre a presença dos anticorpos aCL, beta2-gp1, Hsp 60 e Hsp 65 com os parâmetros clínicos de atividade da doença, com a presença das placas de aterosclerose e com a medida da espessura íntimomedial (IMT) da carótida comum, usando ultra-som (US) modo B de alta resolução foram pesquisadas. Resultados: A idade média no grupo com AR foi 48,93 ± 12,31 vs. 45,37 ± 9,37 no grupo controle saudável (p = 0,20); 90,1% no grupo com AR eram do sexo feminino vs. 86,8% no grupo controle (p = 0,56); índice de massa corporal (IMC) foi 25,72 ± 4,57kg/m² no grupo com AR vs. 26,40 ± 4,52kg/m² no grupo controle (p = 0, 69); Os níveis de colesterol, LDL, triglicerídeos e a relação CT/HDL não foram diferentes quando comparamos os 2 grupos (p > 0,05). O nível de HDL foi maior no grupo com AR vs. grupo controle com 60,56 ± 14,40mg/dl e 54,52 ± 11,55 respectivamente (p = 0,05). A média da medida da IMT foi 0,721 ± 0,16 mm na AR e 0,667 ± 0,14mm no grupo controle, e a IMT dos pacientes com AR foi maior naqueles com idade acima dos 50 anos (P < 0,001). No grupo com AR, 14,1% dos pacientes tinham placas nas carótidas vs. 1,9% dos indivíduos saudáveis (p = 0,02) e no grupo com AR, as placas foram mais frequentes nos pacientes acima dos 50 anos (p = 0,004). No grupo AR, 5,6% tinham anticorpos aCL IgG vs. 3,8% no grupo controle (p > 0,05); 14,1% apresentavam aCL IgM vs. 7,5% (p > 0,05); 43,7% tinham anti-beta2-gp1 IgA vs. 40,8% no grupo controle (p > 0,05). A prevalência de anti-beta2-gp1 IgG e IgM e anti-LPL não foi diferente entre os pacientes com AR e o grupo controle ( p > 0,05). A presença dos anticorpos anti-Hsp 60 e 65 na AR e no grupo controle não foram diferentes (p > 0,05), mas os títulos de anticorpos contra Hsp 65 e beta2-gp1 IgM foram maiores no grupo com AR ( p = 0,007 e p = 0,03 respectivamente). Nós não encontramos associação entre a presença e os títulos dos anticorpos aCL IgG e IgM, beta2-gp1 IgG, IgM e IgA, LPL e Hsp 60 e 65 com a presença de placas nas carótidas ou com a medida da IMT (p > 0,05). Discussão: Este estudo confirma achados anteriores da maior prevalência de aterosclerose carotídea nos pacientes com AR e sua correlação com idade, colesterol e LDL. Embora tenha se encontrado uma tendência a maior presença de anticorpos nos pacientes com AR, não houve relação entre a presença da aterosclerose mais prevalente nos pacientes com AR, com a auto-imunidade dirigida contra cardiolipina, beta2-gp1 ou Hsp. / Purpose: Many questions remain unanswered about the causes of accelerated atherosclerosis in patients with inflammatory systemic diseases such as rheumatoid arthritis (RA). Some studies have suggested the role of autoimmunity besides inflammation in the pathogenesis of atherosclerosis in general population and have also discussed the possible association with antibodies directed to phospholipids and heat shock proteins (Hsp). The aim of this study was to investigate the presence of antibodies against phospholipids, beta2-glycoprotein1 (beta2-gp1), lipoprotein lipase (LPL) and Hsp in RA subjects and evaluate the association between these antibodies with the presence of subclinical carotid atherosclerosis. Methods: Tests to antibodies against cardiolipin (aCL) IgG and IgM, beta2-gp1 IgG, IgM and IgA ,Hsp 60 and Hsp 65 were done by ELISA test in a group of 71 RA subjects compared with 53 age and sex-matched non-RA subjects. Smoking, diabetic and hypertensive patients were excluded in both groups. The lipoprotein levels, clinical parameters of RA, Health Assessment Questionnaire (HAQ), Disease Activity Score (DAS) 28, Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) were evaluated. The association between the presence of antibodies against cardiolipin, beta2-gp1 and Hsp 60 and 65 with the clinical parameters of disease activity in RA, and with the presence of plaques and mean intimo-medial thickness (IMT) of common carotid using high-resolution B-mode ultrasound were assessed. Results: Mean age in RA group was 48.93 ± 12.31 vs. 45.37 ± 9.37 in healthy control group (p = 0.20); 90.1% were women in RA group vs. 86.8% in healthy control (p = 0.56); body mass index (BMI) were 25.72 ± 4.57 in RA group vs. 26.40 ± 4.52 in healthy control (p = 0.69). The levels of cholesterol, LDL, triglycerides, CT/HDL didn t have difference between the two groups (p > 0.05). The HDL was higher in RA group vs. control group with 60.56 ± 14.40mg/dl and 54.52 ± 11.55 respectively (p = 0.05). The mean IMT was 0.721 ± 0.16mm in RA and 0.667 ± 0.14mm in control group, and the IMT was higher in patients older than 50 years among RA subjects (p < 0.001). In RA subjects, 14.1% had carotid plaques vs. 1.9% in healthy controls (p = 0.02). In RA group, the carotid plaques were more frequent in patients older than 50 years (p = 0.004). In RA group, 5.6% had antibodies against cardiolipin IgG vs. 3.8% in control group (p > 0.05); 14.1% in RA group had anti-cardiolipin IgM vs. 7.5% (p > 0.05); 43.7% had anti-beta2-gp1 IgA vs 40.8% in control group (p > 0.05). The presence of anti-beta2-gp1 IgG and IgM, and anti-LPL didn t have significant difference between the groups (p > 0.05). The prevalence of antibodies to Hsp 60 and Hsp 65 were similar in RA and in control group (p > 0.05), but the titers of antibodies against Hsp 65 and beta2-gp1 IgM were higher in RA group (p = 0.007 and p = 0.03 respectively). We didn t find relationship between antibodies against cardiolipin IgG and IgM, or beta2-gp1 IgG, IgM and IgA, LPL, Hsp 60 and 65 with mean IMT or plaque carotid (p > 0.05). Discussion: This study confirms the great prevalence of carotid atherosclerosis in RA subjects and its correlation with age, cholesterol and LDL. Although it was found a tendency to have more autoantibodies in RA subjects, there weren t any link between atherosclerosis in RA with autoimmunity against cardiolipin, beta2-gp 1, LPL or Hsp.
355

"Antilipoproteína lipase (LPL): um novo componente no complexo processo aterosclerótico do lúpus eritematoso sistêmico?" / Antilipoprotein lipase antibodies (aLPL): a new player in the complex atherosclerotic process in systemic lupus erythematosus?

Jozélio Freire de Carvalho 15 August 2005 (has links)
Dislipidemia é implicada no processo aterosclerótico do LES. A descrição de aLPL no LES associado a hipertrigliceridemia levou-nos a analisar esse anticorpo no contexto da inflamação envolvida na aterogênese. aLPL foi encontrado em 38% dos pacientes com LES com altos níveis de triglicérides. Correlação positiva significante foi observada entre aLPL e PCR, VHS, SLEDAI, anti-DNA, anti-cardiolipina e CH100 baixo. Análise de regressão múltipla confirmou a forte associação entre aLPL e PCR. Esses dados dão suporte à associação entre inflamação, resposta imune e dislipidemia, introduzindo o aLPL como um novo componente nos complexos eventos da aterogênese do LES / Dyslipidemia is implicated in the atherosclerosis process of SLE. The description of aLPL in SLE associated with hypertrigliceridemia prompted us to analyze this antibody in the context of the inflammation involved in the atherogenesis. aLPL was found in 38 por cento of SLE patients with high levels of triglycerides. Significant positive correlation was observed between aLPL and CRP, ESR, SLEDAI, anti-DNA, anti-cardiolipin and low CH100. Multiple regression analysis confirmed the strong association between aLPL and CRP. These data support the link between inflammation, immune response and dyslipidemia, introducing anti-LPL as new player in the complex events of atherogenesis in SLE
356

Role of PFOA and PFOS on Serum Apolipoprotein B, NHANES, 2005-2006

Maisonet, Mildred, Yadav, Ruby, Leinaar, Edward 01 September 2015 (has links)
Background: Exposure to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) have been associated with higher circulating concentrations of total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). ApoB is the primary apolipoprotein component of LDL-C, and acts as a ligand for LDL-C receptors in various cells throughout the body. Circulating concentrations of ApoB are considered to be a better indicator of heart disease risk than TC or LDL-C. Objectives: Explore associations of concentrations of PFOA and PFOS with serum ApoB in adults. Methods: We analyzed data from 2744, 20-80 years old participants in the 2005–2006 National Health and Nutrition Examination Survey (NHANES). Linear regression models were used to estimate adjusted predicted means of serum ApoB (in g/L) for quartiles of PFOA and PFOS (in ng/mL) to describe patterns of associations. Results: Adjusted predicted mean concentrations of serum ApoB did not appear to vary meaningfully with increasing concentrations of PFOA (Q1 1.11, Q2 1.02, Q3 1.01, Q4 1.02) or increasing concentrations of PFOS (Q1 1.06, Q2 1.05, Q3 1.07, Q4 0.99) in study participants. Conclusions: Exposure to PFOA or PFOS does not appear to alter Apo B concentrations in adults.
357

Lipids and Endothelium-Dependent Vasodilation / Lipider och endotelberoende vasodilatation

Steer, Peter January 2003 (has links)
<p>Impaired endothelium-dependent vasodilation (EDV) is associated with atherosclerotic cardiovascular disease as well as several of its risk factors.</p><p>The aim of the present thesis was to investigate how lipids influence EDV in the vascular bed of the human forearm.</p><p>Apolipoprotein B was inversely associated with both EDV and endothelium-independent vasodilation (EIDV) in healthy subjects aged 20-69 years. HDL cholesterol was associated with the EDV to EIDV ratio (EFI). Small LDL particles and antibodies against oxidized LDL were not associated with endothelial vasodilatory function.</p><p>The EFI in young, healthy subjects was positively associated with alpha-linolenic acid proportion, but inversely associated with myristic acid in men only. Eicosapentaenoic acid was positively associated with EDV, whereas dihomo-gamma-linolenic acid was inversely associated with both EDV and EIDV in men. </p><p>Acute elevation of long-chain fatty acids with Intralipid<sup>®</sup>/heparin infusion in young, healthy subjects impaired EDV after 2 h. This impairment could be prevented by co-infusing vitamin C, diclophenac or L-arginine. Acute elevation of both medium-chain and long-chain fatty acids during Structolipid<sup>®</sup>/heparin infusion did not impair EDV.</p><p>An ordinary meal (34 E% fat) transiently attenuated EDV at 1 hour. No attenuation in EDV was observed after meals containing 20 and 3 E% fat. </p><p>These findings show that the endothelial vasodilatory function is associated with fatty acid profile in serum in the fasting state and during acute fatty acid elevation, as well as with apolipoprotein B and HDL cholesterol. Furthermore, lowering dietary fat content to 20 E% or less preserves endothelial vasodilatory function and might therefore protect against atherosclerosis.</p>
358

Glucose and lipid metabolism in insulin resistance : an experimental study in fat cells

Burén, Jonas January 2003 (has links)
Type 2 diabetes is usually caused by a combination of pancreatic β-cell failure and insulin resistance in target tissues like liver, muscle and fat. Insulin resistance is characterised by an impaired effect of insulin to reduce hepatic glucose production and to promote glucose uptake in peripheral tissues. The focus of this study was to further elucidate cellular mechanisms for insulin resistance that may be of relevance for type 2 diabetes in humans. We used rat and human adipocytes as an established model of insulin’s target cells. Glucocorticoids, e.g. cortisol, can induce insulin resistance in vivo. In the present study, pretreatment of rat adipocytes in vitro for 24 h with the cortisol analogue dexamethasone produced a downregulation of glucose uptake capacity as well as a marked depletion of cellular insulin receptor substrate 1 (IRS-1) and protein kinase B (PKB), two proteins suggested to play a critical role in the intracellular signal transduction pathway of insulin. The amount of phosphorylated PKB in response to acute insulin treatment was decreased in parallel to total PKB content. The basal rate of lipolysis was enhanced, but insulin’s antilipolytic effect was not consistently altered following dexamethasone pretreatment. Alterations in blood glucose as well as insulin levels may be of great importance for cellular as well as whole-body insulin resistance. High glucose (≥15 mM) for 24 h induced a decrease in glucose uptake capacity in rat adipocytes and IRS-1 content was reduced whereas IRS-2 was increased. Long-term pretreatment with a high insulin concentration downregulated insulin binding capacity and when combined with high glucose, it produced a pronounced reduction of cellular IRS-1 and 2 content together with insensitivity to insulin’s effect to activate PKB and a decrease in glucose uptake capacity. A common denominator for a decrease in glucose uptake capacity in our rat adipocyte studies seems to be a decrease in IRS-1 content. Adipocytes from type 2 diabetes patients are insulin-resistant, but in our work the insulin resistance could be reversed by incubation of the cells at a physiological glucose level for 24 h. Insulin resistance in fresh adipocytes from type 2 diabetes patients was associated with in vivo insulin resistance and glycemic level and with adipocyte cell size and waist-hip ratio (WHR). As a potential mechanism for postprandial dyslipidemia in type 2 diabetes, we examined the nutritional regulation of subcutaneous adipose tissue lipoprotein lipase (LPL) activity. It was upregulated by ~40-50 % after a standardised lipid-enriched meal and this was very similar in type 2 diabetes patients and control subjects, suggesting that the postprandial hypertriglyceridemia found in type 2 diabetes is not explained by an altered nutritional regulation of LPL in subcutaneous fat. In conclusion, the present work provides evidence for novel interactions between glucocorticoids and insulin in the regulation of glucose metabolism that may potentially contribute to the development of insulin resistance. High levels of glucose and insulin produce perturbations in the insulin signalling pathway that may be of relevance for human type 2 diabetes. Cellular insulin resistance may be secondary to the diabetic state in vivo, e.g. via glucotoxicity. This is supported by our finding that insulin resistance in adipocytes from type 2 diabetes patients can be reversed after incubation at a physiological glucose level. Key words: adipocyte, insulin resistance, type 2 diabetes, insulin signalling, glucose uptake, insulin, glucose, dexamethasone, insulin receptor substrate, protein kinase B, GLUT4, lipoprotein lipase.
359

Lipids and Endothelium-Dependent Vasodilation / Lipider och endotelberoende vasodilatation

Steer, Peter January 2003 (has links)
Impaired endothelium-dependent vasodilation (EDV) is associated with atherosclerotic cardiovascular disease as well as several of its risk factors. The aim of the present thesis was to investigate how lipids influence EDV in the vascular bed of the human forearm. Apolipoprotein B was inversely associated with both EDV and endothelium-independent vasodilation (EIDV) in healthy subjects aged 20-69 years. HDL cholesterol was associated with the EDV to EIDV ratio (EFI). Small LDL particles and antibodies against oxidized LDL were not associated with endothelial vasodilatory function. The EFI in young, healthy subjects was positively associated with alpha-linolenic acid proportion, but inversely associated with myristic acid in men only. Eicosapentaenoic acid was positively associated with EDV, whereas dihomo-gamma-linolenic acid was inversely associated with both EDV and EIDV in men. Acute elevation of long-chain fatty acids with Intralipid®/heparin infusion in young, healthy subjects impaired EDV after 2 h. This impairment could be prevented by co-infusing vitamin C, diclophenac or L-arginine. Acute elevation of both medium-chain and long-chain fatty acids during Structolipid®/heparin infusion did not impair EDV. An ordinary meal (34 E% fat) transiently attenuated EDV at 1 hour. No attenuation in EDV was observed after meals containing 20 and 3 E% fat. These findings show that the endothelial vasodilatory function is associated with fatty acid profile in serum in the fasting state and during acute fatty acid elevation, as well as with apolipoprotein B and HDL cholesterol. Furthermore, lowering dietary fat content to 20 E% or less preserves endothelial vasodilatory function and might therefore protect against atherosclerosis.
360

Proprotein convertase subtilisin/kexin type 9 in human disease

Awan, Zuhier 02 1900 (has links)
Les maladies cardiovasculaires (MCV) demeurent au tournant de ce siècle la principale cause de mortalité dans le monde. Parmi les facteurs de risque, l’hypercholestérolémie et l’obésité abdominale sont directement liées au développement précoce de l’athérosclérose. L’hypercholestérolémie familiale, communément associée à une déficience des récepteurs des lipoprotéines de basse densité (LDLR), est connue comme cause de maladie précoce d’athérosclérose et de calcification aortique chez l’humain. La subtilisine convertase proprotéine/kexine du type 9 (PCSK9), membre de la famille des proprotéines convertases, est trouvée indirectement associée aux MCV par son implication dans la dégradation du LDLR. Chez l'humain, des mutations du gène PCSK9 conduisent soit à une hypercholestérolémie familiale, soit à une hypocholestérolémie, selon que la mutation entraîne un gain ou une perte de fonction, respectivement. Il demeure incertain si les individus porteurs de mutations causant un gain de fonction de la PCSK9 développeront une calcification aortique ou si des mutations entraînant une perte de fonction provoqueront une obésité abdominale. Dans cette étude, nous avons examiné : 1) l’effet d’une surexpression de PCSK9 dans le foie de souris sur la calcification aortique ; 2) les conséquences d’une déficience en PCSK9 (Pcsk9 KO), mimant une inhibition pharmacologique, sur le tissu graisseux. Nous avons utilisé un modèle de souris transgénique (Tg) surexprimant le cDNA de PCSK9 de souris dans les hépatocytes de souris et démontrons par tomographie calculée qu’une calcification survient de façon moins étendue chez les souris PCSK9 Tg que chez les souris déficientes en LDLR. Alors que le PCSK9 Tg et la déficience en LDLR causaient tous deux une hypercholestérolémie familiale, les niveaux seuls de cholestérol circulant ne parvenaient pas à prédire le degré de calcification aortique. Dans une seconde étude, nous utilisions des souris génétiquement manipulées dépourvues de PSCK9 et démontrons que l’accumulation de graisses viscérales (adipogenèse) apparaît régulée par la PCSK9 circulante. Ainsi, en l’absence de PCSK9, l’adipogenèse viscérale augmente vraisemblablement par régulation post-traductionnelle des récepteurs à lipoprotéines de très basse densité (VLDLR) dans le tissu adipeux. Ces deux modèles mettent en évidence un équilibre dynamique de la PCSK9 dans des voies métaboliques différentes, réalisant un élément clé dans la santé cardiovasculaire. Par conséquent, les essais d’investigations et d’altérations biologiques de la PCSK9 devraient être pris en compte dans un modèle animal valide utilisant une méthode sensible et en portant une attention prudente aux effets secondaires de toute intervention. / Cardiovascular disease (CVD) is the leading cause of death in the 21st century. Among risk factors, hypercholesterolemia and abdominal obesity are directly linked to premature development of atherosclerosis. Familial hypercholesterolemia, commonly due to low-density lipoprotein receptor (LDLR) deficiency, is known to cause premature atherosclerosis and aortic calcification in humans. Proprotein convertase subtilisin/kexin 9 (PCSK9), a member of the proprotein convertase family, is indirectly associated with CVD through enhanced LDLR degradation. Mutations in the human PCSK9 gene lead to either familial hypercholesterolemia or hypocholesterolemia, depending on whether the mutation causes a gain or a loss of function, respectively. It is uncertain if individuals carrying mutations causing a gain-of-function of PCSK9 will develop aortic calcification or whether loss-of-function mutations will lead to abdominal obesity. In this thesis, we investigated: 1) the effect of PCSK9 overexpression on aortic calcification; 2) the consequences of PSCK9 deficiency, mimicking pharmacological inhibition of PCSK9 on fat tissue. We employed a transgenic (Tg) mouse model overexpressing mouse PCSK9 and illustrated by micro-computerized tomography that calcification occurs to a lesser extent in PCSK9 Tg mice than in LDLR-deficient mice. While both PCSK9 Tg and LDLR deficiency caused familial hypercholesterolemia, circulating cholesterol levels alone could not dictate the degree of aortic calcification. In another study, we used genetically modified mice lacking PCSK9 and demonstrated that visceral fat accumulation (adipogenesis) is regulated by circulating PCSK9. Thus in the absence of PCSK9, visceral adipogenesis increases likely via post-translational regulation of very-low-density lipoproteins receptors (VLDLR) in the adipose tissue. In conclusion, these two studies highlight the dynamic balance of PCSK9 in different metabolic pathways, making it a key element in cardiovascular health. Consequently, attempts to survey and/or alter PCSK9 biology should be performed in a valid animal model using sensitive methods and with careful attention to side effects of any given intervention.

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