State Key Laboratory of Quality Research in Chinese Medicine, Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, China.
J Chromatogr A. 2013 Apr 19;1286:102-10. doi: 10.1016/j.chroma.2013.02.058. Epub 2013 Feb 24.
Methylglyoxal (MGO), a very reactive metabolite of glucose, plays a pivotal role in the pathogenesis of several chronic diseases associated with diabetes, and it has been validated as an attractive target for them. In the present study, a simple and effective method, namely pre-column incubation followed by fast high performance liquid chromatography based on superficially porous particles (shell), coupled with diode array detection and tandem mass spectrometry (UHPLC-DAD-MS(n)), was proposed for rapid and high-throughput screening of natural MGO scavengers directly from the crude extract of Polygonum cuspidatum Sieb. et Zucc, a well-known traditional Chinese medicine which was used for treatment of diabetic complications. The hypothesis is that upon reaction with MGO, the peak areas of components with MGO scavenging potency in the chromatogram will be significantly reduced or disappear, and the structural characterization could be achieved by UHPLC-DAD-MS(n) hyphenated technique. First of all, 12 compounds in P. cuspidatum were well separated within shorter time (~12 min) than previous methods and identified, and two of them, i.e. 3,5,4'-trihydroxystilbene-3-O-(6″-galloyl)-glucoside (3) and emodin-8-O-(6'-malonyl)-glucoside (8) were firstly reported ingredients. After incubation with MGO, four stilbene derivatives were demonstrated to possess potential MGO trapping activities. Furthermore, it was proved that both polydatin (piceid) and resveratrol exhibited effective MGO-trapping capacity by UHPLC analysis, and they could significantly inhibit the formation of advanced glycation end products (AGEs) in the human serum albumin (HSA)-MGO assay, indicating that they were potential candidate agents for delaying and preventing diabetic complications. Additionally, MGO trapping mechanism exploration by UHPLC-MS(n) showed that the positions 2 and 4 of the A ring of stilbene were major active sites for trapping MGO to form both mono- and di-MGO adducts, however, the glucosylation of the hydroxyl group would significantly decrease the trapping efficiency. Collectively, the current work provides a very promising method for rapid discovery of natural MGO scavengers directly from complex matrices such as herbal medicines with huge resources.
甲基乙二醛（MGO）是葡萄糖的一种非常活跃的代谢物，在与糖尿病相关的几种慢性疾病的发病机制中起着关键作用，它已被证实是这些疾病有吸引力的治疗靶点。在本研究中，提出了一种简单有效的方法，即在柱前孵育后，立即使用基于表面多孔颗粒（壳）的快速高效液相色谱法，结合二极管阵列检测和串联质谱法（UHPLC-DAD-MS(n)），从传统中药虎杖的粗提取物中直接快速筛选天然 MGO 清除剂。虎杖是一种用于治疗糖尿病并发症的中药。其假设是，与 MGO 反应后，色谱中具有 MGO 清除能力的成分的峰面积将显著降低或消失，并且可以通过 UHPLC-DAD-MS(n) 联用技术进行结构表征。首先，在比以前的方法更短的时间（约 12 分钟）内，将虎杖中的 12 种化合物分离，并鉴定出来，其中两种，即 3,5,4'-三羟基二苯乙烯-3-O-(6″-没食子酰基)-葡萄糖苷（3）和大黄素-8-O-(6'-丙二酰基)-葡萄糖苷（8），是首次报道的成分。与 MGO 孵育后，四种二苯乙烯衍生物被证明具有潜在的 MGO 捕获活性。此外，通过 UHPLC 分析证明，白藜芦醇和虎杖苷都具有有效的 MGO 捕获能力，它们可以显著抑制人血清白蛋白（HSA）-MGO 测定中晚期糖基化终产物（AGEs）的形成，表明它们是延缓和预防糖尿病并发症的潜在候选药物。此外，通过 UHPLC-MS(n)进行 MGO 捕获机制的探索表明，二苯乙烯 A 环的 2 位和 4 位是捕获 MGO 形成单-和二-MGO 加合物的主要活性位点，然而，羟基的葡萄糖化会显著降低捕获效率。总的来说，这项工作为从草药等复杂基质中直接快速筛选天然 MGO 清除剂提供了一种很有前景的方法，草药具有巨大的资源。
