畜産食品タンパク質をモデルとした合成ペプチドによる生体調節機能の解明

氧化应激与胃肠道粘膜炎症有关。一些研究已经描述了几种动物和植物来源的蛋白质的抗氧化活性。各种蛋白质如蛋清蛋白、蛋黄蛋白、大豆蛋白和牛奶酪蛋白水解后产生的肽具有抗氧化活性。近年来对蛋黄蛋白磷维素和磷维素磷酸肽（PPP）的抗氧化活性进行了研究。一种炎症趋化因子，白细胞介素-8 (IL-8)，是由氧化应激诱导的，抗氧化剂已被证明可以抑制IL-8的表达。过氧化氢可以增加人上皮细胞系中IL-8的产生。我们研究了化学合成的多磷酸丝氨酸作为PPP模型对过氧化氢诱导的肠上皮Caco-2细胞产生IL-8的影响。采用酶联免疫吸附法（ELISA）检测趋化因子的产生。我们发现合成的多磷酸丝氨酸显著抑制过氧化氢诱导的Caco-2细胞IL-8的产生。此外，抑制作用是剂量依赖性的。结果提示，该磷脂肽具有减轻氧化应激引起的肠道炎症的潜力。

Oxidative stress has been implicated in the mucosal inflammation of the gastrointestinal tract. Several studies have described the antioxidant activity of proteins from several animal and plant sources. The antioxidant activity of peptides generated from the hydrolysis of various proteins, such as egg white protein, egg yolk protein, soy protein, and milk casein has been reported. Recent studies have described the antioxidant activity of egg yolk protein phosvitin and phosvitin phosphopeptides (PPP). An inflammatory chemokine, interleukin-8 (IL-8), is induced by oxidative stress, and the antioxidants have been shown to inhibit IL-8 expression. Hydrogen peroxide is known to increase IL-8 production in human epithelial cell lines. We investigated the effect a chemically synthesized poly-phosphoserine as a moldel of PPP on the production of IL-8 induced by hydrogen peroxide in intestinal epithelial Caco-2 cells. The chemokine production was measured by enzyme-linked immunosorbent assay (ELISA). We found that the synthesized poly-phosphoserine significantly inhibited the hydrogen peroxide-induced IL-8 production in Caco-2 cells. Moreover, the inhibition was dose-dependent. The results suggested that the phosphopeptides have the potential to attenuate intestinal inflammation by oxidative stress.