Biochemical characterization of the venom of the Bolivian endemic pit viper Bothrops sanctaecrucis

Abstract

Ophidic accidents are an important public health problem in South America, specifically those related to the Bothrops genus, due to their high incidence, complexity and severity of envenomation symptoms. The species B. sanctaecrucis, the only one from this genus endemic to Bolivia, is the most frequently found and involved in snakebites in the Chapare region of Cochabamba; however, its toxicological implications on human health are poorly known. Herein we conducted the first biochemical characterization of its venom. Its electrophoretic profile showed components mainly ranging from ~10 to 37 kDa, resembling other Bothrops venoms. The venom exhibited high activity on azocasein (47.65 U/mg) and the thrombin specific substrate S-2238 (625.55 μmol/min/mg), and noticeably hydrolyzed gelatin and human fibrin(ogen). The venom also degraded lecithin and hyaluronic acid, but both at low levels. These in vitro results point out a toxic mechanism of action fundamentally at a local level, with tissue damage likely caused (although not exclusively) by SVMPs. Immunochemical reactivity was evaluated against Bothrops antivenoms produced in Argentina, which not only exhibited cross-reaction by Western Blotting but also neutralized the procoagulant activity of the venom. This study offers first insights into the venom components of B. sanctaecrucis, and provides preliminary and important information about the pathophysiological mechanisms involved in the envenomation by this species, paving the way for treatment strategies in such accidents.