基于生物碱及肽类成分研究益母草缩宫止血的药效物质基础

Postpartum hemorrhage (PPH) is a serious obstetric complication which can be life threatening for puerperae during childbirth, and the most common cause of PPH is uterine atony. At present, PPH remains prevalent worldwide not only because the number of valuable drugs is relatively small, but also because the use of the chemical drugs is restricted in some cases. Based on the theories of Traditional Chinese Medicine, we chose motherwort (Leonurus japonicus Houtt.) to study. Conventional wisdom considered that the abundant stachydrine is the main effective substance, however, few related studies have been reported. Thus, the conventional view is difficult to fully elucidate the pharmacodynamic material basis of motherwort. Base on the previous activity research of kinds of compounds in motherwort and the structural features of the common medicine "oxytocin", we put forward the assumption that "alkaloids and peptides are active ingredients for uterine contraction and hemostasis of motherwort, among them, peptides might be the major effective components." Consequently, the active fraction found in previous study is the pointcut in the project. Guided by the uterine contraction activity in vitro, we will isolate and identify the active components by various chromatographic techniques and analytical methods. Then, the uterine contraction and hemostasis effect of the active components will be verified by animal models in vivo. This research will not only explain actual effective substances for uterine contraction and hemostasis of motherwort, but also provide the scientific basis for quality control, and lay the foundation for safe promotion of motherwort and its preparations in the obstetrics department.

产后出血是分娩期危及产妇生命的严重并发症，而子宫收缩乏力是产后出血的主要原因。针对目前临床缩宫止血药物较少及使用存在局限的现象，申请者基于中医药理论的指导，选择妇产科常用的益母草为研究对象。传统观点认为含量较大的水苏碱为益母草主要药效物质，但一直未见深入的研究和报道，难以全面地真实地阐明缩宫止血的物质基础。申请者基于前期对益母草各类成分的活性研究以及常用药物缩宫素的结构特点，提出"益母草生物碱和肽类为缩宫止血有效成分群，其中肽类化合物可能是发挥药效的主体"的假设。在此基础上，本项目以前期发现的益母草有效部位为切入点，以离体子宫收缩活性为导向，利用各种现代色谱技术和分析手段分离鉴定活性成分，以整体动物模型验证其作用。研究工作不仅可阐明益母草缩宫止血的真实药效物质，还可为质量控制提供科学依据，为该中药及其制剂在产科的安全推广奠定基础。

子宫收缩乏力是产后出血的主要原因，严重危及产妇生命。项目承担者基于中医药理论及临床指导，选择经产要药“益母草”为研究对象，并基于前期基础，提出“益母草生物碱和肽类为缩宫止血有效成分群，其中肽类化合物可能是发挥药效的主体”的学术假说。. 在此项目开展过程中，采用现代化学和药理学研究方法，确证了以上学术观点，基本阐明了益母草缩宫止血的物质基础，主要包括：（1）通过动物离体子宫实验，明确了益母草生物碱是益母草缩宫的活性成分群，且水溶性生物碱强于总碱。（2）通过在体子宫实验，验证了益母草生物碱具有显著的缩宫作用，且子宫颈注射效果优于普通肌肉注射，可使豚鼠在体子宫收缩活力、收缩频率、收缩平均值、收缩最大值均显著增加。（3）利用现代色谱技术，获得化合物48个，其中新化合物12个，新颖骨架1个，目标化合物环肽等生物碱28个。（4）发现益母草环肽C和D、益母草碱、西贝素苷、N-异丁基缬氨酸、3-羟基吡啶等生物碱具有明显缩宫活性，推断为主要活性成分。（5）益母草非生物碱类成分均未表现出缩宫作用，进一步表明益母草缩宫的活性成分群为生物碱。（6）益母草中存在辅助成分，可通过配伍达到增效的整体作用。（7）通过药物流产所致豚鼠子宫模型，说明益母草生物碱确有缩宫止血作用，且与降低NO（一氧化氮）含量、增加ET-1（内皮素）含量、升高Ca2+（钙）含量、降低P（孕酮）含量有关。. 本项目利用“动物离体子宫模型—在体子宫模型—流产动物模型”的系统评价手段，证实益母草生物碱显著的缩宫止血作用，达到预期研究目的，取得预期研究成果，对促进益母草及其制剂的临床推广和进一步研究开发具有重要意义。