Protective effect of Dracontium dubium against Bothrops asper venom.

In Colombia, Bothrops asper is responsible for 70-90% of ophidians accidents reported annually. Envenoming occurs mainly in rural areas where both antivenom and health centers are scarce. Thus, patients are frequently treated by local healers that employ medicinal herbs; including several species belonging to Dracontium genus. In this work, we evaluated the neutralizing activity of Dracontium dubium Kunth against the lethal, inflammatory, coagulant and hemolytic effects produced by B. asper venom. Mice treated with D. dubium extract (500 and 1000μg/g, ip), survived to the administration of lethal doses of venom, with remarkable recovery of macroscopic and histology damage. Furthermore, D. dubium exerted a significant inhibition of inflammatory damage promoted by paw injection of B. asper venom. Such activity might be related to the inhibition of macrophage activation and NO production, as demonstrated using LPS-stimulated RAW 264.7 cells. Moreover, the extract of D. dubium remarkably diminished the indirect hemolytic effect of snake venom. On the other hand, no substantial differences were observed in clotting time of plasma incubated with venom when compared to extract treated plasma. Noteworthy, D. dubium extract did not alter the electrophoretic pattern of venom before the assays. Phytochemistry screening revealed the presence of phenolic compounds, flavonoids, tannins and steroids/triterpenoids, which might explain the bioactivity of the extract. Our results, provides strong evidence that support the employment of D. dubium in folk medicine. Further studies are needed to isolate and identify the metabolites responsible for the activity, in order to provide a useful and accessible treatment for snakebite envenoming in low-income rural areas.