Fibrinogenolytic potential of venoms of medically important Brazilian snakes

Abstract

One of the main clinical manifestations presented by victims of snake bite envenoming are coagulation disorders. Considering that fibrinogen is a key molecule for crosslinked fibrin clot formation, the objective of this work was the quantitative analysis of the fibrinogenolytic activity of snakes of medical importance in Brazil and neutralization by specific antivenom. For this, pools of three genera of medical importance (Bothrops, Crotalus and Lachesis) that are used for the production of antivenom were used, and three pools of species of the genus Bothrops that are not part of the pool for the production of antivenom. The Lachesis pool had the highest fibrinogenolytic activity, even demonstrating partial cleavage (42.9 % consumption) of the fibrinogen gamma chain. The Bothrops genus venom pools have shown subtle variations between them. The Crotalus pool, despite not showing total cleavage of any fibrinogen chain, began cleavage of fibrinogen by the beta chain. The specific antivenoms used were able to delay the cleavage of fibrinogen in all the venoms used, which could be the first step towards implementing previous in vitro tests to analyze the quality of the batches of antivenoms produced, thus potentially reducing the use of animals used in this process.

Keywords: Neutralization by antivenom; Three R's principles; γ-Fibrinogenase.