Bhosale Prakash, Serban Bogdan, Zhao Da You, Bernstein Paul S
Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Medical Drive, Salt Lake City, Utah 84132, USA.
Biochemistry. 2007 Aug 7;46(31):9050-7. doi: 10.1021/bi700558f. Epub 2007 Jul 14.
As in humans and monkeys, lutein [(3R,3'R,6'R)-beta,epsilon-carotene-3,3'-diol] and zeaxanthin [a mixture of (3R,3'R)-beta,beta-carotene-3,3'diol and (3R,3'S-meso)-beta,beta-carotene-3,3'-diol] are found in substantial amounts in the retina of the Japanese quail Coturnix japonica. This makes the quail retina an excellent nonprimate small animal model for studying the metabolic transformations of these important macular carotenoids that are thought to play an integral role in protection against light-induced oxidative damage such as that found in age-related macular degeneration (AMD). In this study, we first identified the array of carotenoids present in the quail retina using C30 HPLC coupled with in-line mass spectral and photodiode array detectors. In addition to dietary lutein (2.1%) and zeaxanthin (11.8%), we identified adonirubin (5.4%), 3'-oxolutein (3.8%), meso-zeaxanthin (3.0%), astaxanthin (28.2%), galloxanthin (12.2%), epsilon,epsilon-carotene (18.5%), and beta-apo-2'-carotenol (9.5%) as major ocular carotenoids. We next used deuterium-labeled lutein and zeaxanthin as dietary supplements to study the pharmacokinetics and metabolic transformations of these two ocular pigments in serum and ocular tissues. We then detected and quantitated labeled carotenoids in ocular tissue using both HPLC-coupled mass spectrometry and noninvasive resonance Raman spectroscopy. Results indicated that dietary zeaxanthin is the precursor of 3'-oxolutein, beta-apo-2'-carotenol, adonirubin, astaxanthin, galloxanthin, and epsilon,epsilon-carotene, whereas dietary lutein is the precursor for meso-zeaxanthin. Studies also revealed that the pharmacokinetic patterns of uptake, carotenoid absorption, and transport from serum into ocular tissues were similar to results observed in most human clinical studies.
与人类和猴子一样，叶黄素[（3R，3′R，6′R）-β，ε-胡萝卜素-3，3′-二醇]和玉米黄质[（3R，3′R）-β，β-胡萝卜素-3，3′-二醇与（3R，3′S-内消旋）-β，β-胡萝卜素-3，3′-二醇的混合物]在日本鹌鹑（Coturnix japonica）的视网膜中大量存在。这使得鹌鹑视网膜成为一种出色的非灵长类小动物模型，用于研究这些重要的黄斑类胡萝卜素的代谢转化，这些类胡萝卜素被认为在预防光诱导的氧化损伤（如年龄相关性黄斑变性（AMD）中发现的损伤）方面起着不可或缺的作用。在本研究中，我们首先使用C30高效液相色谱（HPLC）结合在线质谱和光电二极管阵列检测器，鉴定了鹌鹑视网膜中存在的类胡萝卜素种类。除了膳食中的叶黄素（2.1%）和玉米黄质（11.8%），我们还鉴定出adonirubin（5.4%）、3′-氧代叶黄素（3.8%）、内消旋玉米黄质（3.0%）、虾青素（28.2%）、鸡油菌黄质（12.2%）、ε，ε-胡萝卜素（18.5%）和β-阿朴-2′-胡萝卜醇（9.5%）为主要的眼部类胡萝卜素。接下来，我们使用氘标记的叶黄素和玉米黄质作为膳食补充剂，研究这两种眼部色素在血清和眼部组织中的药代动力学和代谢转化。然后，我们使用HPLC联用质谱和非侵入性共振拉曼光谱法检测并定量眼部组织中的标记类胡萝卜素。结果表明，膳食中的玉米黄质是3′-氧代叶黄素、β-阿朴-2′-胡萝卜醇、adonirubin、虾青素、鸡油菌黄质和ε，ε-胡萝卜素的前体，而膳食中的叶黄素是内消旋玉米黄质的前体。研究还表明，从血清摄取、类胡萝卜素吸收以及转运到眼部组织的药代动力学模式与大多数人类临床研究中观察到的结果相似。
