RESUMO
BACKGROUND: Oxidative modification of low-density lipoproteins (LDL) is an essential step in atherogenesis, generating minimally oxidized LDL, also called electronegative LDL [LDL(-)], which has chemotactic, cytotoxic and immunogenic properties. METHODS AND RESULTS: Serum LDL(-) and anti-LDL(-) auto-antibodies (IgG) were evaluated in 28 children and adolescents with familial hypercholesterolemia (FH) antecedents, with or without early coronary artery disease in first-degree relatives (eCAD), hypercholesterolemic (hc) or normocholesterolemic (nc) versus a control group of normocholesterolemic children without pathologic antecedents (C). ELISA method was used for detection of LDL(-) and anti-LDL(-) IgG. LDL(-) serum levels did not differ among the four groups (FH-eCAD-hc 41.4 +/- 24.9 microg/dl; FH-hc 38.3 +/- 11.2 microg/dl; FH-nc 47.3 +/- 17.0 microg/dl and C 44.2 +/- 28.8 microg/dl, p = 0.659). However, IgG anti-LDL(-) auto-antibodies were significantly higher in the control group in comparison to the FH groups with or without eCAD, independent of hypercholesterolemia or normocholesterolemia (FH-eCAD-hc 0.825 +/- 0.289 microg/dl; FH-hc 0.667 +/- 0.307 microg/dl; FH-nc 0.763 +/- 0.204 microg/dl and C 1.105 +/- 0.233 microg/dl, p = 0.006). When the auto-antibodies of groups with FH, with or without eCAD and with or without hypercholesterolemia were compared, no differences were found (p = 0.509). CONCLUSION: These results showed that FH and/or eCAD children and adolescents have lower titers of auto-antibodies anti-LDL(-) than children from normal families, independent of serum LDL-cholesterol or serum LDL(-).
Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Predisposição Genética para Doença , Hiperlipoproteinemia Tipo II/sangue , Imunoglobulina G/imunologia , Lipoproteínas LDL , Adolescente , Adulto , Biomarcadores/sangue , Criança , Pré-Escolar , Colorimetria , Feminino , Humanos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/imunologia , Lipoproteínas LDL/sangue , Lipoproteínas LDL/imunologia , Masculino , Oxirredução , Estudos Retrospectivos , Fatores de RiscoRESUMO
A modificação das lipoproteínas de baixa densidade (LDL) é considerada etapa essencial no processo aterosclerótico, gerando partículas LDL minimamente oxidadas, também chamadas LDL eletronegativas (LDL- ), com propriedades quimiotáticas, citotóxicas e imunogênicas. Estudamos as concentrações séricas de LDL- e de autoanticorpos IgG anti-LDL- mensuradas por ELISA em crianças e adolescentes com antecedentes de Hipercolesterolemia Familiar (AHF), com ou sem Doença Arterial Coronariana precoce em parentes de primeiro grau (ADAC) / Oxidative modification of low-density lipoproteins (LDL) is an essential step in atherogenesis, generating mildly oxidized LDL, also called eletronegative LDL (LDL-), which have chemotactic, cytotoxic and immunogenic properties. We studied plasma concentrations of LDL- and anti-LDL- autoantibodies (IgG) in children and adolescents with Familial Hypercholesterolemia antecedents (FHA), with or without Coronary Artery Disease in first-degree relatives (CADA), hypercholesterolemic (hc) or normocholesterolemic (nc) versus a control group of normocholesterolemic children without pathologic antecedents (C). ELISA method was used. LDL- serum levels were not different in the four groups (FHA-CADA-hc 41,4 ± 24,9; FHA -hc 38,3 ± 11,2; FHA -nc 47,3 ± 17,0 and C 44,2 ± 28,8...