Institute of Chinese Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
J Ethnopharmacol. 2011 Oct 11;137(3):1323-7. doi: 10.1016/j.jep.2011.07.060. Epub 2011 Aug 5.
The root of Rehmannia glutinosa (RR) is commonly used as a wound-healing agent in various traditional Chinese herbal formulae; while angiogenesis is one of the crucial aspects in wound-healing.
The objective of the present study was to investigate the angiogenesis effects of RR aqueous crude extract and its active component(s) using zebrafish model.
The in vivo angiogenesis effect was studied using transgenic TG(fli1:EGFP)(y1)/+(AB) zebrafish embryos by observing the capillary sprouts formation in sub-intestinal vessel (SIV) of zebrafish embryos after 72 h post-fertilization under fluorescence microscopy.
Our results indicated that RR aqueous crude extract (250 μg/ml) exhibited significant angiogenesis effect, with an increase in capillary sprouts formation in SIV. Following sequential solvent partition of the RR aqueous crude extract with dichloromethane, ethyl acetate and n-butanol successively, the dichloromethane fraction (DCM) was found to have the most sprouts formation in the SIV region. Subjected to column chromatography, DCM fraction was further fractionated into six sub-fractions and among these tested, the sub-fraction C2 exhibited the most potent angiogenesis effect. The major component, C2A, was isolated and identified as norviburtinal using nuclear magnetic resonance (NMR) and mass spectrometry (MS). The compound norviburtinal (at 50 μg/ml) was shown to possess significant angiogenesis effect in zebrafish model (p < 0.001).
Norviburtinal was, for the first time, found in the extract of RR and possessed novel angiogenesis effect. Bioassay-guided fractionation suggested that norviburtinal was not the only active component responsible for the angiogenesis effect of RR.
地黄的根通常被用作各种中草药配方中的伤口愈合剂；而血管生成是伤口愈合的关键方面之一。
本研究的目的是使用斑马鱼模型研究地黄水提粗提物及其活性成分的血管生成作用。
通过观察受精后 72 小时斑马鱼胚胎的亚肠血管（SIV）中毛细血管芽的形成，在活体中研究血管生成作用。转基因 TG(fli1:EGFP)(y1)/+(AB)斑马鱼胚胎。
我们的结果表明，地黄水提粗提物（250μg/ml）表现出显著的血管生成作用，可增加 SIV 中的毛细血管芽形成。继用二氯甲烷、乙酸乙酯和正丁醇依次对地黄水提粗提物进行顺序溶剂萃取后，发现二氯甲烷部分（DCM）在 SIV 区域具有最多的芽形成。经柱层析进一步分离，DCM 部分进一步分为六个亚部分，其中亚部分 C2 表现出最强的血管生成作用。主要成分 C2A 被分离并使用核磁共振（NMR）和质谱（MS）鉴定为北美黄连碱。化合物北美黄连碱（50μg/ml）在斑马鱼模型中表现出显著的血管生成作用（p<0.001）。
北美黄连碱首次在地黄提取物中被发现，并具有新的血管生成作用。基于生物测定的分离表明，北美黄连碱不是地黄血管生成作用的唯一活性成分。
