title: Simultaneous screening and analysis of antiplatelet aggregation active alkaloids from Rhizoma Corydalis.
abstract: BACKGROUND
  The rising problem of atherosclerosis and ischemic heart disease emphasizes the need to look for new antithrombotic components with effective modes of action. Corydalis yanhusuo (Y.H. Chou & Chun C. Hsu) W.T. Wang ex Z.Y. Su & C.Y. Wu (Papaveraceae) (Rhizoma Corydalis) has been used in the traditional medicines for the treatment of cardiovascular disease.
  
  
  OBJECTIVE
  The antiplatelet aggregation compounds in Rhizoma Corydalis were screened to validate its traditional medicinal use.
  
  
  METHODS
  Total alkaloid extract (TAE) of Rhizoma Corydalis was obtained by refluxing 100 g Rhizoma Corydalis powder with 600 mL 70% ethanol, and purified by acidification (20% HCl) and alkalization (5 M NaOH) process. Potential antiplatelet aggregation compounds in TAE were screened by a method involving platelet bio-specific extraction and HPLC-DAD/LC-MS analysis. Further in vitro antiplatelet aggregation activity confirmation of TAE and seven main alkaloids were achieved by turbidimetry method within 3 h after blood collection from rabbit carotid artery, and all the test drugs were at the concentration range of 25-350 μg/mL. Finally, HPLC-DAD was employed for the quantitative determination of seven main components in TAE.
  
  
  RESULTS
  Five alkaloids, identified as glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline, can be specifically extracted with platelets. The results indicated that all these five alkaloids can inhibit thrombin-induced platelet aggregation in a low dose (IC50of glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline were 49.057, 34.914, 33.547, 84.261 and 54.164 μg/mL, respectively) as compared to TAE (IC50=175.426 μg/mL) and aspirin (IC50=300.340 μg/mL), while the unbound compounds (palmatine and tetrahydropalmatine) had a very weak antiplatelet effect (IC50>200 μg/mL).
  
  
  CONCLUSIONS
  This study is the first reported work for antiplatelet components screening in Rhizoma Corydalis. Seven compounds were detected and identified by HPLC-DAD/LC-MS, of which five platelet-targeted compounds were discovered.
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Qian
authors: Q
authors: Zhang
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Cen
authors: C
authors: Chen
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Feng-Qin
authors: FQ
authors: Wang
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Chun-Hong
authors: CH
authors: Li
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Qi-Hui
authors: QH
authors: Zhang
authors: b State Key Laboratory of Quality Research in Chinese Medicine , Institute of Chinese Medical Sciences, University of Macau , Macao , P.R. China.
authors: Yuan-Jia
authors: YJ
authors: Hu
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Zhi-Ning
authors: ZN
authors: Xia
authors: a School of Chemistry and Chemical Engineering , Chongqing University , Chongqing , P.R. China.
authors: Feng-Qing
authors: FQ
authors: Yang
mesh_terms: D000470:Alkaloids / Q000032:analysis* / Q000494:pharmacology; D000818:Animals; D031311:Corydalis; D010936:Plant Extracts / Q000032:analysis* / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects* / Q000502:physiology; D010975:Platelet Aggregation Inhibitors / Q000032:analysis* / Q000494:pharmacology; D011817:Rabbits; D027343:Rhizome
chemical_list: D000470:Alkaloids; D010936:Plant Extracts; D010975:Platelet Aggregation Inhibitors
keywords: HPLC/LC–MS; Thromboembolic disease; platelet bio-specific extraction; traditional Chinese medicines