title: Hemostatic properties of Venezuelan Bothrops snake venoms with special reference to Bothrops isabelae venom.
abstract: In Venezuela, Bothrops snakes are responsible for more than 80% of all recorded snakebites. This study focuses on the biological and hemostatic characteristics of Bothrops isabelae venom along with its comparative characteristics with two other closely related Bothrops venoms, Bothrops atrox and Bothrops colombiensis. Electrophoretic profiles of crude B. isabelae venom showed protein bands between 14 and 100 kDa with the majority in the range of 14-31 kDa. The molecular exclusion chromatographic profile of this venom contains five fractions (F1-F5). Amidolytic activity evaluation evidenced strong thrombin-like followed by kallikrein-like activities in crude venom and in fractions F1 and F2. The fibrinogenolytic activity of B. isabelae venom at a ratio of 100:1 (fibrinogen/venom) induced a degradation of A alpha and B beta chains at 15 min and 2 h, respectively. At a ratio of 100:10, a total degradation of A alpha and B beta chains at 5 min and of gamma chains at 24 h was apparent. This current study evidences one of rarely reported for Bothrops venoms, which resembles the physiologic effect of plasmin. B. isabelae venom as well as F2 and F3 fractions, contain fibrinolytic activity on fibrin plate of 36, 23.5 and 9.45 mm(2)/microg, respectively using 25 microg of protein. Crude venom and F1 fraction showed gelatinolytic activity. Comparative analysis amongst Venezuelan bothropoid venoms, evidenced that the LD(50) of B. isabelae (5.9 mg/kg) was similar to B. atrox-Puerto Ayacucho 1 (6.1 mg/kg) and B. colombiensis-Caucagua (5.8 mg/kg). B. isabelae venom showed minor hemorrhagic activity, whereas B. atrox-Parguasa (Bolivar state) was the most hemorrhagic. In this study, a relative high thrombin-like activity was observed in B. colombiensis venoms (502-568 mUA/min/mg), and a relative high factor Xa-like activity was found in B. atrox venoms (126-294 mUA/min/mg). Fibrinolytic activity evaluated with 10 microg protein, showed that B. isabelae venom contained higher specific activity (50 mm(2)/microg) than B. colombiensis and B. atrox venoms, which should encourage the isolation of these fibrinolytic molecules to improve the quality of immunotherapy.
authors.affiliation: Sección de Inmunoquímica, Instituto de Medicina Tropical de la Universidad Central de Venezuela, Caracas, Venezuela.
authors.forename: Alexis
authors.initials: A
authors.lastname: Rodríguez-Acosta
authors.forename: Elda E
authors.initials: EE
authors.lastname: Sánchez
authors.forename: Adriana
authors.initials: A
authors.lastname: Márquez
authors.forename: Zoila
authors.initials: Z
authors.lastname: Carvajal
authors.forename: Ana M
authors.initials: AM
authors.lastname: Salazar
authors.forename: María E
authors.initials: ME
authors.lastname: Girón
authors.forename: Amalid
authors.initials: A
authors.lastname: Estrella
authors.forename: Amparo
authors.initials: A
authors.lastname: Gil
authors.forename: Belsy
authors.initials: B
authors.lastname: Guerrero
mesh_terms: D000581:Amidohydrolases / Q000097:blood; D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D017837:Bothrops / Q000502:physiology*; D003435:Crotalid Venoms / Q000737:chemistry / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D005337:Fibrin / Q000187:drug effects; D005342:Fibrinolysis / Q000187:drug effects*; D005343:Fibrinolytic Agents / Q000737:chemistry / Q000494:pharmacology*; D005780:Gelatin / Q000187:drug effects / Q000378:metabolism; D006470:Hemorrhage / Q000139:chemically induced / Q000473:pathology; D006487:Hemostasis / Q000187:drug effects*; D007928:Lethal Dose 50; D008297:Male; D051379:Mice; D013045:Species Specificity; D014687:Venezuela
chemical_list: D003435:Crotalid Venoms; D005343:Fibrinolytic Agents; D005780:Gelatin; D005337:Fibrin; D000581:Amidohydrolases