“谱效关系与代谢组学联用技术”在铁苋菜抑菌物质的辨识及其作用机制研究中的应用

Aeromonas hydrophila and Aeromonas sobria, which spread widely and caused serious harm in China, are opportunistic pathogens among human beings, animals and aquatilia. The prevention and treatment of these two bacterias were heavily dependent on quinolone antibiotics. However, antibiotic abuse is such a severe social problem that some substitutes of antibiotics are in urgent need. As a kind of Traditional Chinese Medicine (TCM), Acalypha australis Linn. showed obvious antibacterial effect on Aeromonas hydrophila and Aeromonas sobria. In the previous study of our laboratory, some antibacterial constituents of this herb medicine were predicted based on differences of chemical components and pharmacodynamic results from different samples. In this project, “a combined technique of spectrum-effect relationship and metabolomics” was first adopted to define the lead compound of Acalypha australis Linn. We would establish the spectrum-effect relationship through chemometrics and multivariate statistics methods and the results would based on the chemical information by UPLC-MS and UPLC/Q-TOF-MS/MS analysis and the pharmacodynamic results. Briefly speaking, the spectrum-effect relationship was applied to figure out and identify the antibacterial constituents from Acalypha australis Linn. efficiently and then the pharmacological mechanism of these antibacterial constituents were shed light on using the technique of metabolomics. The research approach not only can solve the problem of time-comsuming and low efficiency in recognizing effective constituent from TCM, but also avoid the blindness of probing into pharmacological mechanism of lead compounds. The study will provide theoretical basis for defining a effective lead compound and for their structural modification in TCM.

嗜水气单胞菌和温和气单胞菌是我国流传广泛且危害严重的人、畜和水生动物共患的条件致病菌，目前依赖喹诺酮类抗生素防治的方法易造成抗生素滥用的问题，亟需通过寻找有效替代品来解决。在前期研究中发现，传统中药铁苋菜对嗜水气单胞菌和温和气单胞菌具有明显的抑制作用，我们根据不同来源样品化学成分及药效的差异初步推测出铁苋菜的多个抑菌相关成分。本课题首次采用“谱效关系与代谢组学联用技术”，将UPLC-MS和UPLC/Q-TOF-MS/MS获得的指纹图谱与抑菌效果结合，通过化学计量学和多元统计学方法建立谱效关系，确定铁苋菜的抑菌物质并鉴定化学结构，同时引入代谢组学方法探讨其抑菌机制。该研究思路不仅解决了传统方法寻找中药有效成分周期长、效率低的难题，也避免了常规模式对先导化合物作用机制研究的盲目性，为寻找到一个有效的先导化合物并指导其结构改造提供理论依据。

嗜水气单胞菌在我国流传广泛且危害严重，农业生产上对喹诺酮类抗生素的过分依赖使得我们急需寻找到防治该致病菌的有效替代品。在前期研究中我们发现铁苋菜水提物对嗜水气单胞菌抑制作用非常明显，极具开发前景。本项目采用“谱效关系与代谢组学联用技术”寻找铁苋菜抑菌成分及其作用机制。首先通过建立铁苋菜UPLC/MS指纹图谱分析了14批不同来源样品的化学成分差异，同时评价它们的药效差异，运用4种不同原理的统计方法建立“谱效关系”，找到铁苋菜中9个抑菌成分分别为尼古丁酸、没食子酸、原儿茶酸、对羟基苯甲酸、槲皮素、铁苋菜素以及3个首次从铁苋菜中发现的成分C13H8O8、C22H12O13、C27H22O18；接着选择4类不同抑菌机制的抗菌药红霉素、利福平、万古霉素、诺氟沙星分别与嗜水气单胞菌共培养，提取胞内代谢物后采用UPLC-Q-TOF技术分析代谢谱，运用化学计量学对不同药物处理的细菌代谢谱进行主成分分析，建立与抑菌机制相关联的代谢组学模型，再将铁苋菜作用后的细菌代谢谱代入模型当中，揭示了铁苋菜的多成分多靶点协同作用抑菌机制。该项目提供了一种高效、准确、针对性强的探索中药有效成分和作用机制的研究方法。