两种紫珠属药用植物新型COX-2抑制剂的发现与研究

The discovery and research on COX-2 inhibitors is one of hot spots for the drug development. Natural products, characteristic of chemistry structure and biological activity diversity, are important sources of new type of COX-2 inhibitors with high efficiency and low toxicity. Calliicarpa kwangtungtungensis and Calliicarpa macrophylla, as two characteristic medicinal plants from the Calliicarpa genus and both included in "China Phamcopoeia", are widely used in the treatment of inflammation, however, their anti-inflammatory active constituents and action mechanism are not yet clear. Our preliminary study showed that the middle polar fractions from the two medicinal plants have anti-inflammatory activity, which may be related to the COX-2 inhibitory activity. Moreover, 24 compounds were separated and indentified from the active fraction of Calliicarpa kwangtungtungensis，and the COX-2 inhibitory activity of flavone C-glycosides were reported for the first time. The project would use biological activity as a guide and LC-ESI/MSn technical analysis as a supplement, to fast track, separate and identify the potential active constituents from the two active fractions, evaluate their COX-2 inhibitory activity, focus on the clarification of the action mechanism from the point of NF-κB and MAPKs signal pathways, and make a preliminary study on the structure-activity. The study will lay a solid foundation for the development of novel COX-2 inhibitors, and be of significance for the clarification of anti-inflammatory pharmacodynamic material basis and action mechanism of Calliicarpa kwangtungtungensis and Calliicarpa macrophylla.

COX-2抑制剂的发现是当今新药研发的热点之一。天然产物具有化学结构和生物活性多样性，是发现新型高效低毒COX-2抑制剂的重要来源。紫珠属两种代表性药用植物广东紫珠和大叶紫珠均为《中国药典》收录的常用中药，抗炎活性明确，临床应用广泛，但其抗炎活性成分和机理尚不明确。我们前期发现两者的中等极性部位均具有显著抗炎活性，且与COX-2抑制活性有关；从广东紫珠活性部位分离鉴定了24个单体化合物，并首次发现黄酮碳苷类化合物的COX-2抑制活性。在此基础上，本项目以生物活性为指导、LC-MSn技术为辅助，对两者抗炎活性部位中潜在目标活性成分进行快速有效分离富集和结构鉴定，开展COX-2抑制活性筛选，着重考察其对NF-κB和MAPKs两个信号通路影响，初步阐明其作用机制，并对构效关系进行初步探讨。这将为新型COX-2抑制剂的研发奠定基础，对广东紫珠和大叶紫珠抗炎药效物质基础与作用机制的阐明具有重要意义。

紫珠属两种代表性药用植物广东紫珠和大叶紫珠均为《中国药典》收录的常用中药，抗炎活性明确，临床应用广泛。前期我们发现两者的中等极性部位具有显著的抗炎活性，且与COX-2抑制活性有关，本课题以上述两种紫珠属药用植物为研究对象，开展活性部位化学成分分离鉴定，以及COX-2抑制活性研究。从广东紫珠中共分离得到单体化合物21个单体化合物，其中13个为属首分，主要为黄酮葡萄糖醛酸苷和苯乙醇苷类成分。活性筛选结果显示苯乙醇苷类化合物具有显著COX-2抑制活性，是广东紫珠主要抗炎活性成分；并首次发现黄酮葡萄糖醛酸苷的COX-2抑制活性，且对这类成分的COX-2抑制活性构效关系进行初步探讨。从大叶紫珠活性部位中共分离得到单体化合物30个，其中7个新化合物，12个为属首分，主要为松香烷型二萜和多甲氧基取代的黄酮，活性结果显示，松香烷型二萜类具有一定抑制PGE2生成活性。开展广东紫珠苯乙醇苷类成分提取富集工艺研究，建立了AB-8大孔吸附树脂富集工艺，该工艺简单易行；开展基于苯乙醇苷类成分的不同紫珠属药用植物HPLC指纹图谱研究，利用相似度分析、聚类分析和主成分分析等化学计量方法，对紫珠属药用植物进行快速分析和鉴别。综合以上研究结果，本研究极大丰富了紫珠属药用植物化合物库，基本明确了苯乙醇苷了成分为主要抗炎活性成分，并发现了黄酮葡萄糖醛酸苷类新型COX-2抑制剂，为紫珠属药用植物药效基础的明确奠定了坚实基础。同时，为该属药用植物的进一步开发利用及质量控制提供了有益依据。项目资助发表论文4篇，其中SCI论文1篇，培养硕士研究生3名，其中2名已获得硕士学位，1名在读。 项目投入经费23万，支出22.9698万，各项支出基本与预算相符。