Vishwanathan Rohini, Schalch Wolfgang, Johnson Elizabeth J
a Antioxidants Research Lab , Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University , Boston , MA , USA.
b DSM Nutritional Products Ltd , Kaiseraugst , Switzerland.
Nutr Neurosci. 2016;19(3):95-101. doi: 10.1179/1476830514Y.0000000141. Epub 2015 Mar 9.
Lutein and zeaxanthin are dietary carotenoids that preferentially accumulate in the macular region of the retina. Together with meso-zeaxanthin, a conversion product of lutein in the macula, they form the macular pigment. Lutein is also the predominant carotenoid in human brain tissue and lutein status is associated with cognitive function in adults. The study objective was to evaluate the relationship between retinal and brain lutein and zeaxanthin in humans.
Donated brain tissue (occipital cortex and hippocampus) and matched retina were obtained from the National Disease Research Interchange, a national human tissue resource center which adheres to strict consent and confidentiality procedures. Decedents were men and women aged >50 years who either had normal cognitive function or Alzheimer's disease. Tissues were analyzed using standard lipid extractions followed by analysis on reverse-phase high performance liquid chromatography (HPLC) and normal-phase HPLC (for meso-zeaxanthin).
Macular pigment carotenoids (lutein, meso-zeaxanthin, and zeaxanthin combined) in the retina were significantly related to the combined concentrations of lutein and zeaxanthin in the occipital cortex. When analyzed separately, only retinal lutein (plus meso-zeaxanthin), not zeaxanthin, was significantly related to lutein in the occipital cortex. No correlations were observed with lutein and zeaxanthin in the hippocampus.
Total macular pigment density measured via non-invasive, psychophysical techniques can be used as a biomarker to ascertain brain lutein and zeaxanthin status in clinical studies.
叶黄素和玉米黄质是膳食类胡萝卜素，它们优先在视网膜黄斑区域积聚。与黄斑中叶黄素的转化产物内消旋玉米黄质一起，它们形成黄斑色素。叶黄素也是人类脑组织中的主要类胡萝卜素，并且叶黄素水平与成年人的认知功能相关。本研究的目的是评估人体视网膜和脑中叶黄素与玉米黄质之间的关系。
从国家疾病研究交流中心获取捐赠的脑组织（枕叶皮质和海马体）及匹配的视网膜，该中心是一个全国性的人体组织资源中心，遵循严格的知情同意和保密程序。死者为年龄大于50岁的男性和女性，他们要么具有正常认知功能，要么患有阿尔茨海默病。组织采用标准脂质提取法进行分析，随后通过反相高效液相色谱（HPLC）和正相HPLC（用于内消旋玉米黄质）进行分析。
视网膜中的黄斑色素类胡萝卜素（叶黄素、内消旋玉米黄质和玉米黄质的总和）与枕叶皮质中叶黄素和玉米黄质的总浓度显著相关。单独分析时，只有视网膜叶黄素（加内消旋玉米黄质），而非玉米黄质，与枕叶皮质中的叶黄素显著相关。未观察到与海马体中的叶黄素和玉米黄质存在相关性。
通过非侵入性心理物理学技术测量的总黄斑色素密度可作为一种生物标志物，用于在临床研究中确定脑中叶黄素和玉米黄质的状态。
