Semba R D, Dagnelie G
Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Med Hypotheses. 2003 Oct;61(4):465-72. doi: 10.1016/s0306-9877(03)00198-1.
The carotenoids lutein and zeaxanthin are found in the macula in high concentrations and may play a role in the pathogenesis of age-related macular degeneration (ARMD). Lutein and zeaxanthin may protect the macula and photoreceptor outer segments throughout the retina from oxidative stress and play a role in an antioxidant cascade that safely disarms the energy of reactive oxygen species. Although lutein and zeaxanthin are not essential nutrients, studies are beginning to suggest that they fit the criteria for conditionally essential nutrients. Low plasma lutein and zeaxanthin concentrations or dietary intake are associated with low macular pigment density and increased risk of ARMD. Dietary deprivation of lutein and zeaxanthin in primates causes pathological changes in the macula. Should controlled clinical trials show lutein and/or zeaxanthin supplementation protects against the development or progression of ARMD and other eye diseases, then lutein and zeaxanthin could be considered as conditionally essential nutrients for humans.
类胡萝卜素叶黄素和玉米黄质在黄斑中大量存在，可能在年龄相关性黄斑变性（ARMD）的发病机制中发挥作用。叶黄素和玉米黄质可保护整个视网膜中的黄斑和光感受器外段免受氧化应激，并在安全消除活性氧能量的抗氧化级联反应中发挥作用。尽管叶黄素和玉米黄质并非必需营养素，但研究开始表明它们符合条件必需营养素的标准。血浆中叶黄素和玉米黄质浓度低或饮食摄入量低与黄斑色素密度低及ARMD风险增加有关。灵长类动物饮食中缺乏叶黄素和玉米黄质会导致黄斑出现病理变化。如果对照临床试验表明补充叶黄素和/或玉米黄质可预防ARMD和其他眼部疾病的发生或进展，那么叶黄素和玉米黄质可被视为人类的条件必需营养素。
