促进神经干细胞生长的蕊木属活性成分及作用机制研究

The hippocampus of adult neural stem cells (NSCs) is an important part of plasticity of central nervous system, and the compounds promoted the growth of it, provide new scientific basis for neurodegenerative diseases along with the decline of study and memory abilities. The indole alkaloids is not only an important species in natural drugs, but also the important molecular template for the synthesis drugs containing N atomic, because of diversity and novelty structures. The indole alkaloids promoting neural stem cell to growth have further potential applications value..Our group has long been carrying out the plants alkaloids, bioactivity research and New drug research, and reported the isolation and structure identification, cytotoxic activities and activating NSCs of novel skeletal alkaloids, such as alstoscholarisines A−E, psychotripine, melohenines A–B, melotenine A, (19,20) E/Z alstoscholarine, scholarisine A, and so on. Besides, the applicants has reported cytotoxic activities of novel alkaloids, including 8 bisindole alkaloids--melosuavines A−H, and 9 indole alkaloids--melodinines M−U. Moreover, Previous study found that total alkaloids from Kopsia plants have significant to promote the growth of neural stem cells, And the chemical investigation on leaves of K. officinalis led to the isolation of 29 indole alkaloids, including 15 new ones and 2 very large amounts (methyl chanofruticosinatemethyl and methyl N1-decarbomethoxy-chanofruticosinate), most of them are methyl chanofruticosinate-type alkaloids. This provides the foundation guarantee for further screening and mechanism researchs..The project will study two Kopsia plants. The Kopsia plants have been proven to be good resources of indole alkaloids and the crudes have significant to promote the growth of neural stem cells. Firstly, indole alkaloids of the Kopsia plants are systemic studied by chemical methods, and then the purified alkaloids are evaluated the bioactive for neural stem cells. According to significant bioactivity, choosing the bioactive alkaloids are studied the mechanism by the mammalian neural stem cells. It is expected to provide lead compounds and the scientific basis for neurodegenerative diseases.

海马区成体神经干细胞是中枢神经系统可塑性的重要组成部分，促进其生长的化合物，将对伴有学习记忆能力下降的神经退行性疾病的治疗提供了新的科学依据。吲哚生物碱因其结构多样性与新颖性不仅是天然药物中的重要类群，同时也为合成含N药物提供了重要分子模板。促进神经干细胞生长的吲哚生物碱的发现具有进一步的应用潜力。.申请人近年积累了生物碱识别、分离、纯化和结构鉴定的经验，并发现一系列结构新颖或具有药理活性的生物碱。前期研究发现蕊木属植物中总生物碱具有显著的促进神经干细胞生长的活性，获得了多个蕊木碱甲类型的生物碱，包括15个新颖结构和2个含量极高的生物碱（wko-1和wko-3），为进一步的活性筛选和机制研究提供了基础保障。.本项目选择前期筛选具有促进神经干细胞生长活性的2种蕊木属植物，通过系统生物碱化学，体外活性筛选、作用机制研究，有望为神经退行性疾病的药物研发提供先导化合物和科学依据。

项目共完成云南蕊木(Kopsia officinalis)叶、茎 和钩藤(Uncaria rhynchophylla)生物碱成分研究，共获得不重复生物碱单体95个，其中新颖结构生物碱27个，其中Kopofficines A-H 属于蕊木素类型的新颖结构，kopofficines I-N属于蕊木碱甲类型的新颖结构，kopsiofficines O-U 属于蕊木碱甲类型的新颖衍生物，其中5个被丙酮基取代的衍生物，kopsiofficines V-X属于长春蔓定胺型的新颖结构，另外还有3个四环育亨宾类新化合物，geissoschizic acid, geissoschizic acid N4-oxide和 3β-sitsirikine N4-oxide。利用UPLC-MS/MS对获得的65个蕊木生物碱单体进行二级质谱的数据采集分析，为后续结构的推测鉴定提供依据。完成云南蕊木叶和钩藤中生物碱对神经干细胞增殖的影响，发现2个生物碱对神经干细胞增殖有促进作用，但是作用都不是很明显；11个生物碱对神经干细胞增殖有中等抑制作用，试验结果未发现具有较强促进神经干细胞增殖活性的生物碱。另外还对蕊木碱开展了抗炎活性，抗肿瘤细胞株、抗胶质瘤干细胞的活性筛选，尤其在抗炎活性中C-5位连接丙酮基的生物碱，其抗炎活性与原型化合物有较好活性，为构效关系研究提供基础。在此项目的资助下，发表相关研究论文5篇，其中SCI研究论文4篇；人才培养方面，项目负责人职称晋升，被评为副研究员，协助培养毕业硕博士研究生各1名。