植物中具有多巴胺能神经元保护活性的、稀有Bakkenolide类化合物的定向快速发现及构效关系研究

To search for the bioactive substances with the protective effects of dopaminergic neuron from medicinal plants is an effective method for the research and development of new drugs to treat Parkinson's disease (PD). Our previous research revealed that the extract of Petasites japonicus showed the protective effects of dopaminergic neuron through SH-SY5Y cell screening model, and 13 rare bakkenolides had been isolated and identified from Petasites japonicus, 6 compounds of which were new bakkenolide-type sesquiterpenoids. The biological evaluation exhibited that 10 bakkenolides had the protective effects of dopaminergic neuron. According to these research results, we will analyze and summarize the NMR rules of characteristic bakkenolides. Based on the summarized NMR rules of the characteristic bakkenolides, the bakkenolides in other plants will be tracked and found quickly with the help of the sensitive NMR instrument. Following the fast discovery of characteristic bakkenolides, the isolation and structure elucidation will be performed through the modern chromatography methods and NMR techniques, and the protective effects of dopaminergic neuron and the cytotoxicity of identified compounds will also be evaluated. Then, the structure-activity relationship and the structure modification of the bakkenolides will be carried out, which leads to the discovery of the compounds with high efficiency and low toxicity. Further, some active compounds with high efficiency and low toxicity will be selected and be studied for the permeability of blood-brain barrier and neuron protective mechanism. This project, including our previous results and the coming research work, will not only lead to the NMR-directed fast discovery of natural compounds with high efficiency and low toxicity from plants, but also lay a foundation for the research and development of new drug for treatment of PD.

从植物中寻找具有多巴胺能神经元保护活性的化合物是研究开发新的治疗Parkinson's disease (PD)药物的有效途径之一。经前期研究，利用建立的筛选平台，发现蜂斗菜提取物具有多巴胺能神经元保护活性，并从中分离鉴定13个稀有的bakkenolide型倍半萜(6个为新化合物)，10个显示较强多巴胺能神经元保护活性；在此基础上，总结已鉴定的bakkenolide型倍半萜的NMR规律，结合规律，以NMR导向快速发现、并利用现代色谱手段、继续分离鉴定植物中的bakkenolide型倍半萜，检测其多巴胺能神经元保护活性，并结合结构修饰、构效关系、毒理学研究，发现更高多巴胺能神经元保护活性的bakkenolide型倍半萜，进而研究血脑屏障透过率及初步作用机制，为建立以NMR导向从植物中快速发现高效低毒活性先导化合物提供新的思路、方法与依据，为植物药的研究开发以及防治PD的创新药物研究奠定基础。

帕金森病(Parkinson's disease, PD)的医学研究显示，具有多巴胺能神经元保护活性的化合物，有望研究开发成为治疗PD的药物。利用建立的SH-SY5Y体外细胞筛选平台，结合前期研究工作基础：蜂斗菜提取物以及从中分离到的bakkenolide 型倍半萜类化合物，具有较强的多巴胺能神经元保护活性，以及基于对bakkenolide 型倍半萜类化合物的NMR 特征规律总结建立起来的高效快速发现方法，我们对富含bakkenolide 型倍半萜类的植物蜂斗菜（Petasites japonicus）、掌叶蜂斗菜（P. tatewakianus）等植物中的bakkenolide 型倍半萜类化合物进行了研究，从其活性萃取层中共分离鉴定81个bakkenolide 型倍半萜类化合物。在鉴定的化合物中，新化合物26个。对鉴定的化合物的多巴胺能神经元保护活性进行了研究，显示多数bakkenolide 型倍半萜类化合物具有很好的多巴胺能神经元保护活性，并对化合物的构效关系、部分活性化合物的初步作用机制进行了研究。同时，利用实验室现有条件，结合神经退行性疾病的病理特征，对鉴定化合物的抗神经炎症活性进行了研究，显示多数化合物同时具有神经保护与抗炎活性，为活性化合物的开发利用奠定了基础。通过此项目的研究，建立起一种基于超灵敏NMR高效快速从植物中发现某一类型的活性天然产物的方法，并验证了方法的可行性；新天然产物的发现以及首次分离的化合物进一步揭示了相关药用植物的化学物质基础；具有神经保护与抗炎活性bakkenolide 型倍半萜类化合物，为抗PD的新药研发提供了可能的先导化合物。