【关键词】  Apolipoprotein

    the Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal, Madrid, Spain (HO, PC, DG-C, and MAL)
    the Departamento de Bioquímica y Biología Molecular, Universidad de Alcalá, Alcalá de Henares, Spain (MAL)
    Unidad de Lípidos, Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spain (CG, MB, and MdO)
    the Departamento de Medicina Preventiva y Salud Pública, Universidad Autónoma de Madrid, Spain (FR-A)

    ABSTRACT

    Background:Apolipoprotein (apo) E is a major determinant of plasma lipid concentrations, which in turn influence the plasma concentrations of various fat-soluble vitamins.

    Objective:We aimed to analyze the effect of APOE genotype on fat-soluble antioxidant concentrations in children.

    Design:A total of 926 healthy boys and girls aged 68 y were selected from 4 cities in Spain. APOE genotyping was carried out, and plasma concentrations of lipids, apolipoproteins, and lipid-soluble antioxidants were measured.

    Results:Plasma lipid concentrations were strongly influenced by APOE genotype. The mean plasma concentration of -tocopherol was 21.3 μmol/L, which is one of the highest values ever reported for a population of children. Although plasma concentrations of -tocopherol, -tocopherol, lycopene, and -carotene varied significantly between subjects with different APOE genotypes, most of these differences disappeared after adjustment for lipoprotein-related covariates. Nevertheless, tocopherol concentrations remained elevated in inpiduals with the E2/2 genotype. Multivariate regression analysis showed interactions of APOE genotype with triacylglycerol and apo B in determining -tocopherol concentrations. When subjects were stratified according to major apo E groups, apo B appeared to be the most important predictor of -tocopherol concentrations in all groups, whereas triacylglycerol was identified only in carriers of the E2 allele.

    Conclusions:The association between APOE genotype and lipophilic antioxidant concentrations is dependent mainly on the effect of the polymorphism on lipoprotein concentrations. However, triacylglycerol plays a role in determining the variability of -tocopherol concentrations in E2 carriers only. This suggests that the -tocopherol content in each lipoprotein class varies according to APOE genotype.

    Key Words: Apolipoprotein E  tocopherols  carotenoids  antioxidants  lipoproteins  children

    INTRODUCTION

    Oxidative stress is believed to underlie most prevalent chronic diseases in industrialized countries, such as cancer, atherosclerosis, and neurodegenerative diseases (13). Although morbidity occurs mainly at advanced ages, nutritional factors operating in childhood, which possibly interact with genetic factors, may also contribute to the development of such diseases.

    In plasma, lipoprotein-bound tocopherols and carotenoids protect fatty acids from peroxidation, thereby preserving their function and the normal fate of lipoprotein particles. Plasma concentrations of vitamin E and