title: Antithrombotic effects of a newly purified fibrinolytic protease from Urechis unicinctus.
abstract: BACKGROUND
  The prevalence of thromboembolic disease, one of the top 3 leading causes of mortality worldwide, is being reported continually. More effective and safer antithrombotic drugs may overcome the underlying problems in antithrombotic therapy. In the present work, antithrombotic effects of UFEIII, a newly purified fibrinolytic protease from Urechis unicinctus were evaluated.
  
  
  METHODS
  UFEIII was purified from the marine invertebrate, Urechis unicinctus, using anion exchange and gel filtration chromatography. Molecular weight, fibrinolytic activity and fibrinogenolysis pattern of UFEIII were determined. Furthermore, antithrombotic effects of UFEIII in vivo were investigated through electrical induced carotid arterial thrombosis in rats, FeCl3 induced carotid arterial thrombus model in rabbits and stasis induced vena caval thrombus model in rats.
  
  
  RESULTS
  SDS-PAGE of the purified enzyme showed a single polypeptide chain with molecular weight of 20.8kDa. In fibrin plate assays, UFEIII could not only directly degrade fibrin but also activate plasminogen. The fibrinogenolysis pattern of UFEIII was Aα-chains>Bβ-chains>γ-chain. Moreover, UFEIII could effectively prolong the time to occlusion in electrical induced carotid arterial thrombosis. Besides, both in rabbits and rats, the administration of UFEIII not only prolonged the activated partial thromboplastin time (APTT) and thrombin time (TT) also decreased the fibrinogen (FIB) content. Further, the thrombus lysis was observed after administration of UFEIII both in rabbits and rats.
  
  
  CONCLUSIONS
  UFEIII can possibly be a new potential source of fibrinolytic agent.
authors.affiliation: College of Marine Life Science, Ocean University of China, Qingdao, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Bi
authors.forename: Baoqin
authors.initials: B
authors.lastname: Han
authors.forename: Yilin
authors.initials: Y
authors.lastname: Feng
authors.forename: Zhongqing
authors.initials: Z
authors.lastname: Jiang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Wanshun
authors.initials: W
authors.lastname: Liu
mesh_terms: D000818:Animals; D002852:Chromatography, Ion Exchange; D005260:Female; D005343:Fibrinolytic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D015801:Helminth Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D008297:Male; D051379:Mice; D010447:Peptide Hydrolases / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D011077:Polychaeta / Q000737:chemistry / Q000201:enzymology*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D013927:Thrombosis / Q000188:drug therapy*
chemical_list: D005343:Fibrinolytic Agents; D015801:Helminth Proteins; D010447:Peptide Hydrolases
keywords: Antithrombotic; Fibrinolytic protease; Thrombogenesis; Urechis unicinctus