Chen C-Y Oliver, Milbury Paul E, Collins F William, Blumberg Jeffrey B
Antioxidants Research Laboratory, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA.
J Nutr. 2007 Jun;137(6):1375-82. doi: 10.1093/jn/137.6.1375.
The consumption of polyphenols is associated with a decreased risk of cardiovascular disease. Avenanthramides (AV), alkaloids occurring only in oats, may have anti-atherosclerotic activity, but there is no information concerning their bioavailability and bioactivity in humans. We characterized the pharmacokinetics and antioxidant action of avenanthramide A, B, and C in healthy older adults in a randomized, placebo-controlled, 3-way crossover trial with 1-wk washout periods. Six free-living subjects (3 mol/L, 3 F; 60.8 +/- 3.6 y) consumed 360 mL skim milk alone (placebo) or containing 0.5 or 1 g avenanthramide-enriched mixture (AEM) extracted from oats. Plasma samples were collected over a 10-h period. Concentrations of AV-A, AV-B, and AV-C in the AEM were 154, 109, and 111 micromol/g, respectively. Maximum plasma concentrations of AV (free + conjugated) after consumption of 0.5 and 1 g AEM were 112.9 and 374.6 nmol/L for AV-A, 13.2 and 96.0 nmol/L for AV-B, and 41.4 and 89.0 nmol/L for AV-C, respectively. Times to reach the C(max) for both doses were 2.30, 1.75, and 2.15 h for AV-A, AV-B, and AV-C and half times for elimination were 1.75, 3.75, and 3.00 h, respectively. The elimination kinetics of plasma AV appeared to follow first-order kinetics. The bioavailability of AV-A was 4-fold larger than that of AV-B at the 0.5 g AEM dose. After consumption of 1 g AEM, plasma reduced glutathione was elevated by 21% at 15 min (P < or = 0.005) and by 14% at 10 h (P < or = 0.05). Thus, oat AV are bioavailable and increase antioxidant capacity in healthy older adults.
食用多酚类物质与心血管疾病风险降低有关。燕麦酰胺（AV）是仅存在于燕麦中的生物碱，可能具有抗动脉粥样硬化活性，但关于其在人体中的生物利用度和生物活性尚无相关信息。在一项随机、安慰剂对照、为期1周洗脱期的三交叉试验中，我们对健康老年人中燕麦酰胺A、B和C的药代动力学及抗氧化作用进行了表征。六名自由生活的受试者（3名男性/3名女性；60.8±3.6岁）分别单独饮用360毫升脱脂牛奶（安慰剂）或饮用含有0.5克或1克从燕麦中提取的富含燕麦酰胺混合物（AEM）的脱脂牛奶。在10小时内采集血浆样本。AEM中AV - A、AV - B和AV - C的浓度分别为154、109和111微摩尔/克。食用0.5克和1克AEM后，AV（游离+结合型）的最大血浆浓度，AV - A分别为112.9和374.6纳摩尔/升，AV - B分别为13.2和96.0纳摩尔/升，AV - C分别为41.4和89.0纳摩尔/升。两种剂量达到C(max)的时间，AV - A、AV - B和AV - C分别为2.30、1.75和2.15小时，消除半衰期分别为1.75、3.75和3.00小时。血浆AV的消除动力学似乎符合一级动力学。在0.5克AEM剂量下，AV - A的生物利用度比AV - B高4倍。食用1克AEM后，血浆还原型谷胱甘肽在15分钟时升高21%（P≤0.005）且在10小时时升高14%（P≤0.05）。因此，燕麦中的AV具有生物利用度，并能提高健康老年人的抗氧化能力。
