火殃簕及其近缘植物抗HIV活性二萜的药物资源研究

The multidrug resistance and side effect are the most serious problem for the treatment of HIV infection. It is essential to continue to develop new antiretroviral drugs with potency against an ever-wider range of viral mutants including those which engender resistance to multidrug classes, and natural products from medicinal plant and fungi are important sources of new drugs. As part of a search for anti-HIV agents of natural origin, a bioactive investigation of 23 medicinal plants and 347 pure compounds were studied to ascertain their potential anti-HIV activity. As a result, three crude extracts of Euphorbia antiquorum and E. royleana were found to significantly inhibit HIV-1. Bioassay-guided phytochemical investigation resulted in the isolation of one bioactive extract and four atisen-type diterpenoids with anti-HIV activities. Based on our preliminary research, the current project will include: (1) The phytochemical investigation of the chemical constituents of E. antiquorum, E. neriifolia and E. royleana in order to isolate more diterpenoids as anti-HIV leading compounds. We will use an X4 virus NL4-3 and an R5 virus HIV-1 BaL for initial evaluation of the anti-HIV activity of the proposed plant extracts and pure compounds in CEM-CCR5 cells. (2) The analysis of the content and distribution of these active compounds in the above 3 plants, and the search for abailable resources containing these anti-HIV diterpenoids from the other related plants of the genus Euphorbia. (3) The structural modification study on biactive compound which has large quantity and was identified as an main anti-HIV principle of E. antiquorum. (4) The anti-HIV bioactive evaluation of the corresponding atisane derivatives and the summarization of their structure-activity relationship. Based on the above work, the initial determination of mechanisms of action of the most active compound will be conducted. This study will provide solid scientific evidence for the exploitation of E. antiquorum and its related plants, as well as the development of new anti-AIDS drugs.

耐药性和毒副作用是目前治疗艾滋病临床用药最为严重的问题。从传统中药、植物和真菌资源中寻找新的抗HIV药物或先导化合物，是国内外新药研制中非常活跃的领域。申请者发现大戟属植物火殃簕和金刚纂3个极性部位具有显著的抗HIV活性，活性导向分离获得活性部位和4个活性程度不等的阿替生烷型二萜。本项目将: (1) 选择3种大戟属植物（火殃簕、金刚篆和霸王鞭）进行系统的化学成分研究，评价分离得到化合物的抗HIV活性；(2) 分析活性化合物在3种植物中的含量和分布特点，从大戟属近缘植物中深入挖掘含有抗艾滋病毒活性的二萜药物新资源；(3) 对前期工作中发现的量大的活性化合物进行结构修饰研究。(4) 在活性化合物分离和结构修饰的研究基础上，探讨阿替生烷型二萜抗HIV的构效关系，并对高活性化合物的抗HIV作用机理进行研究，为火殃簕及其近缘植物的开发利用与抗HIV活性先导化合物的发现奠定基础

耐药性和毒副作用是目前治疗艾滋病临床用药最为严重的问题，需要不断地创制出新的高效、低毒、价廉的抗HIV药物和寻找抗HIV作用的新靶标。从传统中药、植物和真菌资源中寻找新的抗HIV药物或先导化合物的研究，是国内外新药研制中非常活跃的领域。本项目对火殃勒及其四种近缘植物，即金刚纂、霸王鞭、千金子和甘遂，进行了系统的化学成分研究，重点关注其中的二萜类成分和抗HIV活性。此外，还对分离得到的单体化合物进行了逆转肿瘤多药耐药、选择性抑制胶质瘤干细胞、抗肿瘤、NO生成抑制和抗流感病毒活性的筛选和评价。.目前，已完成对上述5种大戟属有毒药用植物的化学成分研究，从中共分离鉴定了246个化合物，包括178个二萜类化合物和67个新化合物。发现了18个具有显著抗HIV活性的化合物，其中从金刚纂中得到的二萜化合物64和从甘遂中得到的二萜化合物188的活性最为显著，IC50值分别为0.0028和0.0035μg/ml。可通过启动PKC依赖的NF-κB来刺激病患体内的两个主要的HIV隐匿区，将HIV“赶出”储存库。对64和188进行结构修饰得到18个衍生物，其中254和255活性最强，可激活潜伏期的HIV病毒从而达到抗病毒作用，可作为抗HIV的活性先导化合物进行深入研究。从大戟属植物中分离得到的千金子烷型和假白榄烷型二萜可显著逆转肿瘤多药耐药，活性最为显著的是从千金子中得到的化合物167，在20μM浓度下的逆转倍数为448.39，为P-糖蛋白上与阿霉素竞争性结合的底物；还发现了系列二萜具有NO生成抑制作用，具有潜在的抗炎活性；发现二萜化合物34和214具有显著的抗流感病毒活性。此外，还对甘遂半夏汤的抗肝癌及抑制癌性腹水的活性进行了体内和体外评价，对其抗肝癌的作用机制进行了初步研究，并基于ATP1A1靶点探讨了甘遂化学物质基础的抗肿瘤作用机制。本项目为火殃勒及其近缘植物的开发利用，以及抗HIV和抗肿瘤活性先导化合物的发现提供了药效物质基础和理论依据。