Yamashita Kanae, Yamada Yasushi, Kitou Shiho, Ikeda Saiko, Abe Chisato, Saarinen Niina M, Santti Risto
Department of Food and Nutrition, Sugiyama Jogakuen University, Nagoya, Japan.
J Nutr Sci Vitaminol (Tokyo). 2007 Oct;53(5):393-9. doi: 10.3177/jnsv.53.393.
We have previously reported that sesame seed with the tetrahydrofurofuran type lignans sesamin and sesaminol (SeOH) produced higher tocopherol concentrations, while flaxseed with the dibenzylbutyrolactone type lignans did not cause higher tocopherol concentrations in rats. Sesame seeds also contain the dibenzylbutyrolactone type lignan 7-hydroxymatairesinol (HMR). To clarify whether or not the tocopherol elevating effect is affected by the chemical structure of lignans, the effect of HMR isolated from Norway spruce, was compared with SeOH, isolated from sesame seed. The lignans were added to a low alpha-tocopherol (10 mg/kg) diet, and rats were maintained on these diets for 8 wk. The experimental diet containing 0.2% SeOH elevated alpha-tocopherol content in the plasma liver, kidney, and brain, but HMR (0.2% or 0.5%) had no effects. Dietary HMR and SeOH (both in concentrations of 0.2%) were further compared in rats fed on a gamma-tocopherol (50 mg/kg) containing diet. SeOH produced significantly higher g-tocopherol content in the plasma and tissues, and significantly lower 2,7,8-trimethyl-2(2'-carboxyethyl)-6-hydroxychroman (gamma-CEHC, a gamma-tocopherol metabolite) content in the urine. However, HMR did not show such effects. These results suggest that the sesame lignan SeOH increases tocopherol concentrations in animals by suppressing the conversion of gamma-tocopherol to gamma-CEHC. HMR, a structurally different plant lignan, does not have such properties. Further studies are needed to show the potential health effects associated with an increased tocopherol concentration in the body.
我们之前曾报道，含有四氢呋喃型木脂素芝麻素和芝麻素醇（SeOH）的芝麻能产生更高的生育酚浓度，而含有二苄基丁内酯型木脂素的亚麻籽在大鼠体内并未导致更高的生育酚浓度。芝麻还含有二苄基丁内酯型木脂素7-羟基罗汉松脂素（HMR）。为了阐明生育酚升高效应是否受木脂素化学结构的影响，将从挪威云杉中分离得到的HMR与从芝麻中分离得到的SeOH的效应进行了比较。将这些木脂素添加到低α-生育酚（10毫克/千克）的饮食中，大鼠在这些饮食上维持8周。含有0.2% SeOH的实验饮食提高了血浆、肝脏、肾脏和大脑中的α-生育酚含量，但HMR（0.2%或0.5%）没有效果。在以含γ-生育酚（50毫克/千克）的饮食喂养的大鼠中，进一步比较了饮食中的HMR和SeOH（浓度均为0.2%）。SeOH使血浆和组织中的γ-生育酚含量显著升高，尿液中的2,7,8-三甲基-2(2'-羧乙基)-6-羟基色满（γ-CEHC，γ-生育酚的一种代谢产物）含量显著降低。然而，HMR没有显示出这样的效果。这些结果表明，芝麻木脂素SeOH通过抑制γ-生育酚向γ-CEHC的转化来提高动物体内的生育酚浓度。HMR，一种结构不同的植物木脂素，不具有这样的特性。需要进一步的研究来表明体内生育酚浓度升高所带来的潜在健康影响。
