ABSTRACT
INTRODUÇÃO: A aterosclerose acelerada foi demonstrada em algumas doenças autoimunes, principalmente lúpus eritematoso sistêmico e artrite reumatóide. Embora a alta prevalência do uso de corticosteróides possa ser um fator complicador, por causa de seus efeitos prejudiciais em diversos fatores de risco, acredita-se que, nesses pacientes, a inflamação sistêmica per se desempenhe papel importante na aterogênese. MÉTODOS: Avaliamos a aterosclerose subclínica e os níveis plasmáticos de LDL eletronegativa circulante em pacientes com espondilite anquilosante (EA). Catorze pacientes que atendiam aos critérios de Nova York modificados para EA foram comparados com 13 controles equiparados. Avaliamos a espessura da íntima-média (EIM) na carótida por ultrassonografia bilateral da artéria carótida comum, artéria carótida interna e na bifurcação. Os grupos foram homogêneos, no que tange a fatores de risco cardiovasculares. Apenas um paciente no grupo de EA estava sendo medicado com corticosteróide. RESULTADOS: A presença de inflamação ativa foi demonstrada por BASDAI elevado e níveis mais elevados de PCR em pacientes versus controles (12,36 vs. 3,45 mg/dl, P=0,002). Não observamos diferença na EIM da carótida entre os dois grupos, em qualquer local da artéria. A média de EIM (6 mensurações em 3 locais pré-especificados, bilateralmente) foi 0,72 ± 0,28 no grupo de EA e 0,70 ± 0,45 mm nos controles (P=0,91). Também não observamos diferença significativa na LDL minimamente modificada entre pacientes e controles (14,03 ± 17,40 vs. 13,21 ± 10,21; P=0,88). CONCLUSÕES: Pacientes com EA não demonstraram aumento na EIM da carótida, em comparação com controles. Do mesmo modo, os níveis plasmáticos circulantes de LDL(-) não diferiram significativamente nos dois grupos.
INTRODUCTION: Accelerated atherosclerosis has been shown in some autoimmune diseases, mainly in Systemic Lupus Erythematosus and Rheumatoid Arthritis. Although high prevalence of corticosteroids use may be a confounding factor due to their detrimental effects on several risk factors, systemic inflammation per se is supposed to play an important role in atherogenesis in these patients. METHODS: We have evaluated sub-clinical atherosclerosis and plasma levels of circulating electronegative LDL, which represents the fraction of LDL that is minimally modified, in patients with ankylosing spondylitis (AS). Fourteen patients who fulfilled the modified New York criteria for AS were compared with 13 paired controls. Carotid intimal-media thickness (IMT) was assessed by ultrasonography bilaterally in common carotid artery, internal carotid artery and in the bifurcation. Groups were homogeneous regarding cardiovascular risk factors. Only a single patient in AS group was in use of corticosteroid. RESULTS: The presence of active inflammation was demonstrated by elevated BASDAI and higher CRP levels and in patients versus controls (12.36 vs. 3.45 mg/dl, P = 0.002). No difference was found in carotid IMT between both groups, in any site of artery. Averaged IMT (6 measurements, at 3 pre-specified sites bilaterally) was 0.72 ± 0.28 in AS group and 0.70 ± 0.45 mm in controls (P = 0.91). Minimally modified LDL did not differ significantly either between patients and controls (14.03 ± 17.40 vs. 13.21 ± 10.21; P = 0.88). CONCLUSIONS: Patients with AS did not show increased carotid IMT in comparison to controls. In the same way, circulating plasma levels of LDL (-), did not differ significantly in both groups.
Subject(s)
Female , Humans , Male , Middle Aged , Atherosclerosis/blood , Atherosclerosis/etiology , Lipoproteins, LDL/blood , Spondylitis, Ankylosing/blood , Spondylitis, Ankylosing/complications , Atherosclerosis/diagnosis , Cross-Sectional Studies , Risk FactorsABSTRACT
In order to determine the effect of antibodies against electronegative low-density lipoprotein LDL(-) on atherogenesis, five groups of LDL low receptor-deficient (LDLr-/-) mice (6 per group) were immunized with the following antibodies (100 µg each): mouse anti-LDL(-) monoclonal IgG2b, rabbit anti-LDL(-) polyclonal IgG or its Fab fragments and mouse irrelevant monoclonal IgG and non-immunized controls. Antibodies were administered intravenously one week before starting the hypercholesterolemic diet (1.25 percent cholesterol) and then every week for 21 days. The passive immunization with anti-LDL(-) monoclonal IgG2b, polyclonal antibody and its derived Fab significantly reduced the cross-sectional area of atherosclerotic lesions at the aortic root of LDLr-/- mice (28.8 ± 9.7, 67.3 ± 17.02, 56.9 ± 8.02 µm² (mean ± SD), respectively) compared to control (124.9 ± 13.2 µm²). Vascular cell adhesion molecule-1 protein expression, quantified by the KS300 image-analyzing software, on endothelium and the number of macrophages in the intima was also decreased in aortas of mice treated with anti-LDL(-) monoclonal antibody (3.5 ± 0.70 per field x 10) compared to controls (21.5 ± 3.5 per field x 10). Furthermore, immunization with the monoclonal antibody decreased the concentration of LDL(-) in blood plasma (immunized: 1.0 ± 1.4; control: 20.5 ± 3.5 RLU), the amount of cholesterol oxides in plasma (immunized: 4.7 ± 2.7; control: 15.0 ± 2.0 pg COx/mg cholesterol) and liver (immunized: 2.3 ± 1.5; control: 30.0 ± 26.0 pg COx/mg cholesterol), and the hepatic content of lipid hydroperoxides (immunized: 0.30 ± 0.020; control: 0.38 ± 0.15 ng/mg protein). In conclusion, antibodies against electronegative LDL administered intravenously may play a protective role in atherosclerosis.