Department of Anatomy and Cell Biology, Technion-Israel Institute of Technology, Haifa, Israel.
Adv Exp Med Biol. 2013;756:99-104. doi: 10.1007/978-94-007-4549-0_13.
Oral peroxidases (OPO) consist mainly of salivary peroxidase and myeloperoxidase and are involved in oral defense mechanisms. Salivary peroxidase is synthesized and secreted by salivary glands, whereas myeloperoxidase is found in polymorphonuclear leukocytes, which migrate into the oral cavity at gingival crevices. Green tea is the world's second most popular drink after water. Polyphenols are the most biologically active group of tea components. The purpose of our study was to elucidate the interaction between green tea & EGCG (Epigallocatechin 3-gallate), its main polyphenol and OPO. In previous studies we have shown that elderly trained people who drink green tea for 3 months, have a higher level of OPO activity compared to non-drinkers. Thus, we decided to extend our project in order to understand the above observations by studying the interaction of green tea and OPO both in vitro and in vivo. Addition of green tea and black tea infusions (50 μl/ml) and EGCG (50 μM) to saliva, resulted in a sharp rise of OPO activity +280% (p = 0.009), 54% (p = 0.04) and 42% (p = 0.009), respectively. The elevation of OPO activity due to addition of green tea and EGCG was in a dose dependent manner: r = 0.91 (p = 0.001) and r = 0.637 (p = 0.019), respectively. Also, following green tea infusion mouth rinsing, a rise of OPO activity was observed: +268% (p = 0.159). These results may be of great clinical importance, as tea consumer's oral epithelium may have better protection against the deleterious effects of hydroxyl radicals, produced by not removed hydrogen peroxides in the presence of metal ions. Higher OPO activity upon green tea drinking may provide an extra protection against oxidative stress in the oral cavity.
口腔过氧化物酶（OPO）主要由唾液过氧化物酶和髓过氧化物酶组成，参与口腔防御机制。唾液过氧化物酶由唾液腺合成和分泌，而髓过氧化物酶存在于多形核白细胞中，这些白细胞迁移到牙龈沟中的口腔。绿茶是继水之后世界上第二大受欢迎的饮料。多酚是茶中最具生物活性的一组成分。我们研究的目的是阐明绿茶和 EGCG（表没食子儿茶素没食子酸酯）与其 OPO 之间的相互作用，EGCG 是其主要的多酚。在之前的研究中，我们已经表明，连续 3 个月饮用绿茶的老年训练者的 OPO 活性水平高于不饮用者。因此，我们决定扩展我们的项目，以通过研究绿茶和 OPO 在体外和体内的相互作用来理解上述观察结果。将绿茶和红茶浸液（50μl/ml）和 EGCG（50μM）添加到唾液中，导致 OPO 活性升高 280%（p=0.009）、54%（p=0.04）和 42%（p=0.009）。由于添加绿茶和 EGCG 导致 OPO 活性升高呈剂量依赖性：r=0.91（p=0.001）和 r=0.637（p=0.019）。此外，在绿茶浸液漱口后，观察到 OPO 活性升高：+268%（p=0.159）。这些结果可能具有重要的临床意义，因为茶消费者的口腔上皮可能具有更好的保护作用，防止在存在金属离子时未去除的过氧化氢产生的羟基自由基的有害影响。饮用绿茶后 OPO 活性的升高可能为口腔氧化应激提供额外的保护。
