Yonekura Lina, Kobayashi Miyuki, Terasaki Masaru, Nagao Akihiko
National Food Research Institute, NARO, Tsukuba, Ibaraki 305-8642, Japan.
J Nutr. 2010 Oct;140(10):1824-31. doi: 10.3945/jn.110.126466. Epub 2010 Aug 25.
Fucoxanthin, a xanthophyll present in brown algae consumed in Eastern Asia, can suppress carcinogenesis and obesity in rodents. We investigated the metabolism, tissue distribution, and depletion of fucoxanthin in ICR mice by comparison with those of lutein. The experiments comprised 14-d dietary supplementation with lutein esters or fucoxanthin, followed by 41- or 28-d, respectively, depletion periods with carotenoid-free diets. After lutein ester supplementation, 3'-hydroxy-ε,ε-caroten-3-one and lutein were the predominant carotenoids in plasma and tissues, accompanied by ε,ε-carotene-3,3'-dione. The presence of these keto-carotenoids in mouse tissues is reported here for the first time, to our knowledge. Lutein and its metabolites accumulated most in the liver (7.51 μmol/kg), followed by plasma (2.11 μmol/L), adipose tissues (1.01-1.44 μmol/kg), and kidney (0.87 μmol/kg). The half-life of the depletion (t(1/2)) of lutein metabolites varied as follows: plasma (1.16 d) < liver (2.63 d) < kidney (4.44 d) < < < adipose tissues (>41 d). Fucoxanthinol and amarouciaxanthin A were the main metabolites in mice fed fucoxanthin and partitioned more into adipose tissues (3.13-3.64 μmol/kg) than into plasma, liver, and kidney (1.29-1.80 μmol/kg). Fucoxanthin metabolites had shorter t(1/2) in plasma, liver, and kidneys (0.92-1.23 d) compared with those of adipose tissues (2.76-4.81 d). The tissue distribution of lutein and fucoxanthin metabolites was not associated with their lipophilicity, but depletion seemed to be slower for more lipophilic compounds. We concluded that mice actively convert lutein and fucoxanthin to keto-carotenoids by oxidizing the secondary hydroxyl groups and accumulate them in tissues.
岩藻黄质是一种存在于东亚人食用的褐藻中的叶黄素，它可以抑制啮齿动物的癌症发生和肥胖。我们通过与叶黄素进行比较，研究了岩藻黄质在ICR小鼠体内的代谢、组织分布和消耗情况。实验包括用叶黄素酯或岩藻黄质进行14天的饮食补充，随后分别用不含类胡萝卜素的饮食进行41天或28天的消耗期。补充叶黄素酯后，3'-羟基-ε,ε-胡萝卜素-3-酮和叶黄素是血浆和组织中的主要类胡萝卜素，同时伴有ε,ε-胡萝卜素-3,3'-二酮。据我们所知，这些酮类胡萝卜素在小鼠组织中的存在在此首次被报道。叶黄素及其代谢产物在肝脏中积累最多（7.51 μmol/kg），其次是血浆（2.11 μmol/L）、脂肪组织（1.01 - 1.44 μmol/kg）和肾脏（0.87 μmol/kg）。叶黄素代谢产物消耗的半衰期（t(1/2)）变化如下：血浆（1.16天）<肝脏（2.63天）<肾脏（4.44天）<<<脂肪组织（>41天）。岩藻黄质醇和阿玛鲁西亚黄质A是喂食岩藻黄质的小鼠中的主要代谢产物，且在脂肪组织中的分配量（3.13 - 3.64 μmol/kg）比在血浆、肝脏和肾脏中（1.29 - 1.80 μmol/kg）更多。与脂肪组织（2.76 - 4.81天）相比，岩藻黄质代谢产物在血浆、肝脏和肾脏中的t(1/2)较短（0.92 - 1.23天）。叶黄素和岩藻黄质代谢产物的组织分布与其亲脂性无关，但亲脂性更强的化合物消耗似乎更慢。我们得出结论，小鼠通过氧化仲羟基将叶黄素和岩藻黄质积极转化为酮类胡萝卜素并将它们积累在组织中。
