特色蒙药可吸收入血的防治代谢综合症靶向成分研究

Traditional Mongolian meals are rich in milk and meat, which contain high levels of lipids and calories, constituting a diet that can cause obesity, high blood pressure, high blood lipids, fatty liver, type II diabetes, and other diseases that form the metabolic syndrome (Reaven syndrome). Through many years of practice, Mongolians have developed a medicinal regimen of herbal drugs to maintain health, including the flower of Scabiosa atropurea and other S. species, the fruit of Choerospondias axillaries, the flower of Gossampinus malabarica, the Wood of Xanthoceras sorbifolia, which are used frequently in Mongolian medicine but rarely found in traditional Chinese medicine. The bioactive components of these medicines have not been determined. Because insulin resistance is a major underlying cause of metabolic syndrome and because oxidative stress is linked to insulin resistance, we select DPPH radical as a target molecule, as well as alpha-glucosidase and lipase, which are important targets of therapeutic drugs for type II diabetes and obesity. We will apply an ultrafiltration-LC/MS method to quickly identify the potential bioactive components. The procedure and principle can be briefly described as following: incubate herbal extracts with the target molecules, ultrafilter the complex of bioactive compounds and target molecules, and analyze the filtrate by UHPLC-MS. The bioactive components that bond to the enzymes or react with DPPH will disappear or decrease in the UHPLC-MS charts compared with extracts without target molecules. In addition, the extracts will be fed to rats to determine which components can be absorbed by blood analysis. Based on these data and guided by UHPLC-MS, we will separate and purify the compounds that can bond or react with the target molecules and be absorbed in vivo. On obtaining the pure compounds, we will calculate their EC50 or IC50 values and measure their ability to prevent OH- radical-induced DNA breakage. In addition, the most promising compounds will be prepared on a large scale to determine whether they can mitigate insulin resistance in animal models. We expect to identify new bioactive natural compounds, determine their chemical structures, determine their mechanisms of action, and examine the synergistic actions of the components with various chemical types and mechanisms of action. Through publication of this research, we will increase the publicity of Mongolian medicine, a major branch of traditional Chinese medicine, and provide data for the modernization of preparations of Mongolian medicines.

蒙族传统饮食材料富含高脂肪高热量的奶和肉类，易导致代谢综合症，包括肥胖、高血压、高血脂、脂肪肝和二型糖尿病等。为了防治这些疾病，蒙古民族发展了以降药为主的蒙药体系，常用兰盆花、广枣、木棉花、文冠木等中药很少用的特色药材。现代药理学认为胰岛素抵抗是代谢综合症的引发因素，而氧化应激与胰岛素抵抗密切相关，因此本项目将以DPPH游离基为检测氧化应激的靶分子之一，另外，以II型糖尿病药物靶点α-葡萄糖苷酶及抗肥胖症药物靶点脂肪酶为靶分子，对兰盆花、广枣、木棉花和文冠木的活性成分进行研究。用超滤-液质联用快速筛选提取物中可与靶分子反应或亲和的成分，并结合动物实验，测定入血成分。对既能与靶分子结合又能吸收入血的潜在有效成分，用液质联用指导分离纯化和结构测定。测定纯成分对羟基自由基引起的DNA断裂的保护作用，结合胰岛素抵抗动物实验等，发现新型的防治代谢综合症活性成分，揭示其作用机理。

蓝盆花、广枣、木棉花、文冠木为特色蒙药，临床常出现在防治心血管疾病、肝脏疾病或糖尿病等与代谢综合征相关的蒙药复方中。因此，研究这些药材的有效成分是寻找抗代谢综合征药物先导化合物的有效途径。本研究以抗氧化和抑制α-葡萄糖苷酶活性为指标，结合细胞水平和体内吸收实验，以这几种特色蒙药材为原料，通过超滤-液质联用技术结合传统植物化学方法对其进行提取分离，并对有效成分进行结构改造和新资源研究，寻找抗氧化缓解胰岛素抵抗的药物先导化合物。结果从蓝盆花中分离鉴定出19种成分，其中黄酮类（木犀草素糖苷等）和绿原酸类成分有较强的清除自由基活性，黄酮类成分较易吸收入血。从广枣中分离鉴定出柠檬酸、奎宁酸、没食子酸、原儿茶酸、鞣花酸等20多个成分，没食子酸和鞣花酸对DPPH有很强的清除能力同时也能吸收入血。从木棉花中分离鉴定出黄酮和酰胺类等化合物，其中7个酚类成分有清除DPPH自由基活性，槲皮素和芒果苷对麦芽糖酶有抑制作用，芒果苷也较易吸收入血，动物实验显示木棉花可明显改善STZ诱导的糖尿病大鼠症状和生化指标。从文冠木中分离鉴定出儿茶素类及其低聚物、二氢黄酮醇和黄酮醇类等10多种成分，儿茶素、表儿茶素、杨梅素和二氢杨梅素等具有清除DPPH自由基能力并可保护过氧自由基诱导的DNA链断裂也可吸收入血，表没食子儿茶素-(4 β→8, 2 β→O-7)-表儿茶素可抑制α-葡萄糖苷酶。为了进一步提高儿茶素类成分的细胞穿透力，对其进行了亲脂性衍生化，得到儿茶素和表儿茶素的乙酰化物与丙酮缩合物，细胞穿透力和活性显著增强；进而对亲脂性异戊烯基黄酮也进行了研究，得到的包括新结构在内的亲脂性异戊烯基黄酮及类似物对α-葡萄糖苷酶抑制活性增强。以上研究阐述了这四种特色蒙药的活性成分和作用，并为研发防治代谢综合症药物提供了先导化合物信息。