基于孤儿受体BRS-3配体的中药活性成分研究

Discovery of exogenous ligands for orphan receptor BRS-3 from Chinese herbs

BRS-3受体为蛙皮素样受体家族中的孤儿受体,其信号转导机制以及生物学功能备受关注,寻找BRS-3的配体对于研究受体功能有重要意义。该研究基于激活BRS-3受体可以引起细胞内Ca^(2+)浓度变化这一生物学特征,利用FLIPR Tetra系统进行细胞水平的配体筛选。该实验从400余种中药单体化合物中首次发现从延胡索中分离的单体yuanhunine、从甘草中分离的单体sophoraisoflavanone A和licoriphenone对BRS-3受体有不同程度的拮抗作用。基于HEK293-BRS-3模式细胞的研究结果显示,yuanhunine、sophoraisoflavanone A和licoriphenone浓度依赖性地抑制[D-Phe^(6),β-Ala^(11),Phe^(13),Nle^(14)]bombesin-(6-14)激活BRS-3受体所引起的钙流响应,IC;依次为8.58、4.10、2.04μmol·L^(-1)。进一步研究表明,yuanhunine和sophoraisoflavanone A对BRS-3具有较好的受体选择性。该研究首次发现来源于中药的单体成分具有孤儿受体BRS-3的拮抗活性,为BRS-3受体的深入研究提供了工具药,为新药发现提供了可能的先导化合物,同时为基于中药活性成分的创新药物研发提供了参考。

Bombesin receptor subtype-3(BRS-3)is an orphan receptor in the bombesin receptor family.Its signal transduction mechanism and biological function have attracted much attention.Seeking the ligand for BRS-3 is of great significance for exploring its function.Considering the fact that the activation of BRS-3 receptor can induce the change in intracellular Ca^(2+)concentration,the fluo-rometric imaging plate reader(FLIPR)was utilized for ligand screening at the cellular level.Among more than 400 monomeric compounds isolated from Chinese herbs,yuanhunine from Corydalis Rhizoma and sophoraisoflavanone A and licoriphenone from Glycyrrhizae Radix et Rhizoma antagonized BRS-3 to varying degrees.It was confirmed in HEK293 cells expressing BRS-3 that yuanhunine,sophoraisoflavanone A,and licoriphenone inhibited the calcium current response after the activation of BRS-3 by[D-Phe^(6),β-Ala^(11),Phe^(13),Nle^(14)]bombesin-(6-14)in a dose-dependent manner with the IC;values being 8.58,4.10,and 2.04μmol·L^(-1),respectively.Further study indicated that yuanhunine and sophoraisoflavanone A exhibited good selectivity for BRS-3.In this study,it was found for the first time that monomers derived from Chinese herbs had antagonistic activity against orphan receptor BRS-3,which has provided a tool for further study of BRS-3 and also the potential lead compounds for new drug discovery.At the same time,it provides reference for the research and development of innovative drugs based on the active ingredients of Chinese herbs.