Search of foods inhibiting 12/15-lipoxygenase for prevention of atherosclerosis.

LDL的氧化修饰是动脉粥样硬化发展的关键步骤之一。 以往的研究表明，巨噬细胞中高表达的12/15-脂氧合酶实质上参与了细胞外LDL的氧化过程。我们评估了12种中国茶对12/15-脂氧合酶活性的抑制作用。 已知茶儿茶素如表没食子儿茶素没食子酸酯表现出12/15-脂氧合酶抑制。 青山露水，其中含有较低的儿茶素水平比其他测试的茶，抑制12/15-脂氧合酶的活性。 为了鉴定抑制12/15-脂氧合酶的组分，我们通过反相HPLC分离提取物，并发现含有有效抑制活性的级分。采用电喷雾质谱、1H-NMR和13 C-NMR等方法对各组分进行了分离和分析。 结果表明，这些化合物均为新的单萜苷类化合物。

Oxidative modification of LDL is one of the critical steps for the development of atherosclerosis. Previous study demonstrated that 12/15-lipoxygenase highly expressed in macrophages is essentially in the process of extracellular LDL oxidation. We evaluated the inhibitory effect of 12 Chinese teas on 12/15-lipoxygenase activity. Tea catechins such as epigallocatechin gallate have been known to exhibit 12/15-lipoxygenase inhibition. Qing Shan Lu Shui, which contains lower catechin levels than the other tested teas, suppressed 12/15-lipoxygenase activity. To identify component(s) that inhibited 12/15-lipoxygenase, we fractionated the extract by reverse-phase HPLC and found fractions containing a potent inhibitory activity. The components in the fractions were isolated and analyzed by electro spray-ionization mass spectrometry, 1H-NMR and 13C-NMR. The results suggested that these compounds were novel monoterpenoid glycosides.