title: Browplasminin, a condensed tannin with anti-plasmin activity isolated from an aqueous extract of Brownea grandiceps Jacq. flowers.
abstract: BACKGROUND
  Following Venezuelan traditional medicine, females with heavy menstrual blood loss (menorrhagia) drink Brownea grandiceps Jacq. flowers (BG) decoctions to reduce the bleeding. In a previous study, we demonstrated that BG aqueous extract (E) possesses a potent anti-fibrinolytic activity capable of inhibiting plasmin, the main serine-protease that degrades fibrin. It is widely known that plasmin inhibitors are often used as anti-fibrinolytics to reduce bleeding during surgeries with high risk of blood loss such as cardiac, liver, vascular, tooth extraction and large orthopedic procedures, as well as for menorrhagia treatments. The aim of this work was to isolate and characterize from BGE the compound responsible for the reported anti-fibrinolytic activity.
  
  
  METHODS
  A decoction of BG was prepared; then it was homogenized, centrifuged and lyophilized to obtain BGE. Subsequently the extract was fractionated by gel filtration and reverse phase using HPLC and the active compound was characterized by MALDI-ToF MS. The kinetic parameters of anti-plasmin activity were evaluated by an amidolytic assay using a chromogenic substrate; also the anti-plasmin activity was estimated by fibrin plate method. Data were analyzed by nonparametric statistics.
  
  
  RESULTS
  The active compound was a condensed tannin denominated Browplasminin, which is capable of inhibiting the plasmin activity in a dose-dependent manner when measured in fibrin plates or by the amidolytic activity method; it also has a minor effect on the FXa activity. However, it does not affect the activity of other serine-proteases such as trypsin, t-PA or u-PA. Browplasminin consists predominately of heteroflavan-3-ols of catechin with B-type linkages, and extents up to heptadecamers (~ 5000Da), with hexose residues attached to the polymer that presents a high degree of galloylation. Its IC50for plasmin was 47.80μg/mL and for FXa was 237.08μg/mL, while the Ki were 0.76 and 61.61μg/mL for plasmin and FXa, respectively.
  
  
  CONCLUSIONS
  The overall outcome of this study suggests that Browplasminin could be responsible for reducing heavy menstrual bleeding in women because its kinetic parameters showed that is a good plasmin inhibitor.
authors.affiliation: Laboratorio de Neurofarmacología Celular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela.
authors.forename: Betzabeth
authors.initials: B
authors.lastname: Pereira
authors.affiliation: Laboratorio de Neurofarmacología Celular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela. Electronic address: jbrazon@ivic.gob.ve.
authors.forename: Josmary
authors.initials: J
authors.lastname: Brazón
authors.affiliation: Unidad de Proteómica, Centro de Biología Estructural, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela.
authors.forename: Mónica
authors.initials: M
authors.lastname: Rincón
authors.affiliation: Unidad de Proteómica, Centro de Biología Estructural, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela.
authors.forename: Eva
authors.initials: E
authors.lastname: Vonasek
mesh_terms: D000933:Antifibrinolytic Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae / Q000737:chemistry*; D005341:Fibrinolysin / Q000037:antagonists & inhibitors*; D035264:Flowers; D047348:Hydrolyzable Tannins; D020128:Inhibitory Concentration 50; D008519:Medicine, Traditional; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014687:Venezuela
chemical_list: D000933:Antifibrinolytic Agents; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; C000620990:browplasminin; D005341:Fibrinolysin
keywords: Acetonitrile (PubChem CID: 6342); Ammonium acetate (PubChem CID: 517165); Aprotinin (PubChem CID: 22833874); Benzamidine (PubChem CID: 80289); Brownea; Calcium chloride (PubChem CID: 5284359); Cesium chloride (PubChem CID: 24293); Coagulation; Fibrinolysis; Galloylation; Hydrochloride acid (PubChem CID: 313); Imidazole (PubChem CID: 795); Proanthocyanidins; Sodium chloride (PubChem CID: 5234); Tannin; Tranexamic acid (PubChem CID: 5526); Trifluoroacetic acid (PubChem CID: 6422); Trizma base (PubChem CID: 6503); ε-aminocaproic acid (PubChem CID: 564)