Graduate School of Agriculture, Tokai University, Japan.
Department of Bioscience, School of Agriculture, Tokai University, Japan.
Arch Biochem Biophys. 2020 Oct 30;693:108586. doi: 10.1016/j.abb.2020.108586. Epub 2020 Sep 15.
The accumulation of advanced glycation end-products (AGEs) correlates with aging and accompanies the onset of age-related diseases, such as diabetes and arteriosclerosis. Therefore, a daily intake of natural compounds that inhibit the production of AGEs may be beneficial in preventing these diseases. In this study, we evaluated the inhibitory effects of 14 natural crude extracts, including those of Drosera species, which possess anti-inflammatory activity, on the formation of AGEs, such as N-(carboxymethyl)arginine (CMA) and N-(carboxymethyl)lysine (CML). Crude extracts of Drosera inhibited the formation of CMA and CML by incubation on gelatin with ribose more effectively than with other extracts, so active compounds that prevent AGE formation were purified from Drosera tokaiensis, which is endemic to Japan. Several compounds were purified from D. tokaiensis extracts using HPLC and identified by NMR analysis. These compounds included ellagic acid, 3,3'-di-O-methylellagic acid 4'-glucoside, myricitrine, and quercimelin. Furthermore, all compounds showed a significantly higher inhibitory effect on CMA and CML formations than aminoguanidine. Specifically, ellagic acid and myricitrine had the highest inhibitory effects of the compounds tested. However, not all compounds showed inhibition of CMA formation in a mixture of gelatin and glyoxal (GO). These results suggest that the compounds in D. tokaiensis inhibit CMA and CML formations via the antioxidative activity of phenolic compounds, rather than GO trapping action. This study provides the first evidence that D. tokaiensis inhibits CMA and CML formations and that phenolic compounds such as ellagic acid and myricitrine play an important role as active components of D. tokaiensis extracts.
糖基化终产物（AGEs）的积累与衰老有关，并伴随着与年龄相关的疾病的发生，如糖尿病和动脉硬化。因此，每天摄入能抑制 AGEs 生成的天然化合物可能有助于预防这些疾病。在这项研究中，我们评估了 14 种天然粗提取物对 AGEs（如 N-（羧甲基）精氨酸（CMA）和 N-（羧甲基）赖氨酸（CML））形成的抑制作用，这些提取物包括具有抗炎活性的茅膏菜属植物。与其他提取物相比，茅膏菜属植物的粗提取物在与核糖孵育时更有效地抑制 CMA 和 CML 的形成，因此从日本特有的东亚茅膏菜中纯化出了能防止 AGE 形成的活性化合物。使用 HPLC 从 D. tokaiensis 提取物中分离出几种化合物，并通过 NMR 分析鉴定。这些化合物包括鞣花酸、3,3'-二-O-甲基鞣花酸 4'-葡萄糖苷、杨梅素和 quercimelin。此外，所有化合物对 CMA 和 CML 形成的抑制作用均明显高于氨基胍。具体而言，鞣花酸和杨梅素是测试化合物中抑制作用最强的两种化合物。然而，并非所有化合物在明胶和乙二醛（GO）的混合物中均能抑制 CMA 的形成。这些结果表明，D. tokaiensis 中的化合物通过酚类化合物的抗氧化活性抑制 CMA 和 CML 的形成，而不是通过 GO 捕获作用。本研究首次证明，东亚茅膏菜抑制 CMA 和 CML 的形成，并且鞣花酸和杨梅素等酚类化合物是东亚茅膏菜提取物的重要活性成分。
