Department of Chemical and Life Sciences, Waterford Institute of Technology, Waterford, Ireland.
Invest Ophthalmol Vis Sci. 2010 May;51(5):2636-43. doi: 10.1167/iovs.09-4397. Epub 2010 Jan 27.
Age-related macular degeneration (AMD) is the most common cause of blindness in older people in developed countries, and risk factors for this condition may be classified as genetic and environmental. Apolipoprotein E is putatively involved in the transport of the macular pigment (MP) carotenoids lutein (L) and zeaxanthin (Z) in serum and may also influence retinal capture of these compounds. This study was designed to investigate the relationship between macular pigment optical density (MPOD) and ApoE genotype.
This was a cross-sectional study of 302 healthy adult subjects. Dietary intake of L and Z was assessed by food frequency questionnaire, and MPOD was measured by customized heterochromatic flicker photometry. Serum L and Z were measured by HPLC. ApoE genotyping was performed by direct polymerase chain reaction amplification and DNA nucleotide sequencing from peripheral blood.
Genotype data were available on 300 of the 302 (99.3%) subjects. The mean (+/- SD) age of the subjects in this study was 47.89 +/- 11.05 (range, 21-66) years. Subjects were classed into one of three ApoE genotype groups, as follows: group 1, epsilon2epsilon2 or epsilon2epsilon3; group 2, epsilon3epsilon3; group 3, epsilon2epsilon4 or epsilon3epsilon4 or epsilon4epsilon4. All three groups were statistically comparable in terms of age, sex, body mass index, cigarette smoking, and dietary and serum levels of L and Z. There was a statistically significant association between ApoE genotype and MPOD. Subjects who had at least one epsilon4 allele had a higher MPOD across the macula than subjects without this allele (group 1 MPOD area, 0.70 +/- 0.40; group 2 MPOD area, 0.67 +/- 0.42; group 3 MPOD area, 0.85 +/- 0.46; one-way ANOVA, P = 0.014.
These results suggest that ApoE genotype status is associated with MPOD. This association may explain, at least in part, the putative protective effect of the epsilon4 allele for AMD and is consistent with the view that apolipoprotein profile influences the transport and/or retinal capture of circulating L and/or Z.
年龄相关性黄斑变性（AMD）是发达国家老年人失明的最常见原因，这种疾病的危险因素可分为遗传和环境因素。载脂蛋白 E 据称参与了黄斑色素（MP）类胡萝卜素叶黄素（L）和玉米黄质（Z）在血清中的转运，并且可能还会影响这些化合物在视网膜上的捕获。本研究旨在研究 MPOD 与 ApoE 基因型之间的关系。
这是一项对 302 名健康成年受试者的横断面研究。通过食物频率问卷评估 L 和 Z 的饮食摄入量，并用定制的双色闪烁光度法测量 MPOD。通过 HPLC 测量血清 L 和 Z。通过外周血直接聚合酶链反应扩增和 DNA 核苷酸测序进行 ApoE 基因分型。
本研究中 302 名（99.3%）受试者的基因型数据可用。该研究中受试者的平均（+/- SD）年龄为 47.89 +/- 11.05（范围，21-66）岁。受试者分为以下三种 ApoE 基因型组之一：组 1，epsilon2epsilon2 或 epsilon2epsilon3；组 2，epsilon3epsilon3；组 3，epsilon2epsilon4 或 epsilon3epsilon4 或 epsilon4epsilon4。在年龄、性别、体重指数、吸烟、饮食和血清中 L 和 Z 水平方面，这三组在统计学上无差异。ApoE 基因型与 MPOD 之间存在统计学显著关联。至少携带一个 epsilon4 等位基因的受试者的黄斑区 MPOD 高于不携带该等位基因的受试者（组 1 MPOD 面积，0.70 +/- 0.40；组 2 MPOD 面积，0.67 +/- 0.42；组 3 MPOD 面积，0.85 +/- 0.46；单因素方差分析，P = 0.014）。
这些结果表明 ApoE 基因型与 MPOD 相关。这种关联至少可以部分解释 epsilon4 等位基因对 AMD 的保护作用，并且与载脂蛋白谱影响循环 L 和/或 Z 的转运和/或视网膜捕获的观点一致。
