黑柄炭角菌抗抑郁活性成分研究及其生物合成潜力挖掘

At present, hundreds of millions of people are suffering from depression worldwide. Moreover, the number of depressed patients is increasing every year, which are threatening physical and mental health of human being. Therefore, the development of new antidepressants has become a hot spot. Xylaria nigripes is a traditional medicinal fungus with antidepressant effects. However, the effective material basis of X. nigripes is not clear yet. Our initiative studies have found that the extracts of two strains of X. nigripes (strains A and B) from different origins have antidepressant activity, which can improve the depression-like behavior of mice, as well as the expression level of brain-derived neurotrophic factor (BDNF). Studies have shown that the main components of the active portion of the two strains are novel structural alkaloids derived from PKS/NRPS biosynthetic pathway. In particular, whole-genome sequencing of strain A revealed a group of unknown PKS/NRPS biosynthetic gene clusters, indicating that it has greater biosynthesis potential. Based on the preliminary work, this project plans to study the active secondary metabolites of X. nigripes by UPLC-HRMS/MS and active-directed separation technology. Chemical epigenetic modification method and OSMAC strategy will be utilized to activate silent gene cluster, in order to deeply explore the biosynthesis potential and obtain new natural products. The antidepressant effects of those secondary metabolites will be evaluated on cell levels and animal models. The active components of X. nigripes will be researched in this project, which will probably promote the research and discovery of lead compound for antidepressants.

抑郁症患病人数高达数亿，且逐年上升，严重危害人类健康，因而新型抗抑郁药的开发已成为当今的研究热点。黑柄炭角菌作为具有抗抑郁作用的传统药用真菌，其药效物质基础尚不明确。前期研究发现两株不同产地来源的黑柄炭角菌（菌种A和B）的提取物均有抗抑郁活性，能改善小鼠抑郁样行为，提高BDNF表达水平。初步研究显示两株菌的活性部位主要成分为PKS/NRPS来源的新颖结构生物碱，菌种A的全基因组测序发现多种未知PKS/NRPS生物合成基因簇，表明其具有较大的生物合成潜力。本项目拟在前期工作基础上，基于UPLC-HRMS/MS和活性导向，采用表观遗传修饰法及OSMAC策略，激活沉默基因，挖掘目标菌的生物合成潜力，获得新型天然产物；在细胞水平和动物模型上初步评价化合物抗抑郁作用，探明黑柄炭角菌抗抑郁活性物质基础，发现新型抗抑郁先导化合物。

抑郁症患病人数高达数亿，且逐年上升，严重危害人类健康，因而新型抗抑郁药的开发已成为当今的研究热点。本项目前期研究发现两株不同产地来源的传统药用真菌黑柄炭角菌（菌种A和B）的提取物均有抗抑郁活性，能改善小鼠抑郁样行为，提高BDNF表达水平，但其药效物质基础尚不明确。菌种A全基因组测序发现多种未知PKS/NRPS生物合成基因簇，表明其具有较大的生物合成潜力。随后基于UPLC-HRMS/MS和活性导向，采用表观遗传修饰法及OSMAC策略，系统研究了目标菌的合成次生代谢产物的潜力，分离鉴定了50余个包括萘酮衍生物二聚体、苯二酚类化合物、倍半萜、氨基酸衍生物在内的代谢产物，进一步丰富其药效成分，为其临床应用提供了药效物质基础。单体化合物的活性测试发现多个化合物能显著提高OGD诱导的PC12细胞的细胞活力和抑制细胞凋亡进而发挥神经保护活性，部分化合物能提高C6星型胶质瘤细胞中BDNF水平，为新型抗抑郁先导化合物的发现提供了研究基础。此外，项目基于“细分原子类型的训练集”开发了一种GIAO 13C化学位移计算新方法，为天然产物结构研究提供了便利。基于本项目目前已经发表了SCI论文6篇，申请国家发明专利1项，参与培养硕士研究生3名，另有3篇SCI论文待投稿。