Department of Biophysics, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland.
Department of Nutritional Sciences, The University of Arizona, 1657 East Helen Street, Tucson, AZ 85721, USA.
Nutrients. 2020 May 7;12(5):1333. doi: 10.3390/nu12051333.
Diet-based xanthophylls (zeaxanthin and lutein) are conditionally essential polar carotenoids preferentially accreted in high concentrations (1 mM) to the central retina, where they have the capacity to impart unique physiologically significant biophysical biochemical properties implicated in cell function, rescue, and survival. Macular xanthophylls interact with membrane-bound proteins and lipids to absorb/attenuate light energy, modulate oxidative stress and redox balance, and influence signal transduction cascades implicated in the pathophysiology of age-related macular degeneration. There is exclusive transport, sequestration, and appreciable bioamplification of macular xanthophylls from the circulating carotenoid pool to the retina and within the retina to regions required for high-resolution sensory processing. The distribution of diet-based macular xanthophylls and the lutein metabolite meso-zeaxanthin varies considerably by retinal eccentricity. Zeaxanthin concentrations are 2.5-fold higher than lutein in the cone-dense central fovea. This is an ~20-fold increase in the molar ratio relative to eccentric retinal regions with biochemically detectable macular xanthophylls. In this review, we discuss how the differences in the specific properties of lutein and zeaxanthin could help explain the preferential accumulation of zeaxanthin in the most vulnerable region of the macula.
基于饮食的类胡萝卜素（玉米黄质和叶黄素）是条件必需的极性类胡萝卜素，优先在高浓度（1mM）下积聚在中央视网膜，在那里它们具有赋予独特的生理意义的生物物理生化特性的能力，这些特性与细胞功能、恢复和存活有关。黄斑类胡萝卜素与膜结合蛋白和脂质相互作用，以吸收/衰减光能，调节氧化应激和氧化还原平衡，并影响信号转导级联，这些级联与年龄相关性黄斑变性的病理生理学有关。从循环类胡萝卜素库到视网膜，以及在视网膜内到需要高分辨率感觉处理的区域，黄斑类胡萝卜素具有独特的转运、隔离和可观的生物放大作用。基于饮食的黄斑类胡萝卜素和叶黄素代谢物中-玉米黄质的分布在视网膜的偏心度上有很大的差异。在圆锥密集的中央凹中，玉米黄质的浓度比叶黄素高 2.5 倍。这相对于具有生物化学可检测的黄斑类胡萝卜素的偏心视网膜区域，摩尔比增加了约 20 倍。在这篇综述中，我们讨论了叶黄素和玉米黄质的特定性质的差异如何有助于解释玉米黄质在黄斑最脆弱区域的优先积累。
