Evaluation of Moquiniastrum floribundum extracts on the total venom action of Crotalus durissus terrificus B D Ortolan, C. F. B. Rodrigues, H. H. Gaeta, M. M.H. Toyama

Abstract

Snakebites are currently classified as a new class of neglected tropical disease, representing a serious public health problem in Brazil. The clinical complications caused by poisoning result from the ineffectiveness of commercial antivenoms in neutralizing local effects, such as hemorrhage and necrosis that can lead, in more serious cases, to amputations of the affected limbs. Seeking to reduce these effects, alternative methods such as the use of plant extracts that can act as antivenom enhancers, increasing its effectiveness and neutralizing factors that traditional serotherapy is not effective. In Brazil, the use of plant extracts to treat diseases is very common, however there is still a very wide range of vegetables with possible therapeutic potential, but which have not yet been studied. The Asteraceae family includes Moquiniastrum floribundum , a species from the savannah that is little described and still lacks morphological, phytochemical and pharmacological properties of its extracts, such as potential snake antivenin action. This study evaluated the enzymatic activity of M. floribundum extracts on the total venom of Crotalus durissus terrificus , popularly known as rattlesnake, in order to prove the plant's efficiency as a therapeutic agent. From seven extracts obtained: hexonic phase (E1), dichloromethane phase (E2), ethyl acetate phase (E3), n-butanolic phase (E4), hydroalcoholic phase (E5), hexonic extract phase (E6), methanolic extract (E7), the enzyme inhibition test was carried out by incubating them with total venom. Three tests were carried out covering the 3 main actions of the total poison. In order to verify the anti-coagulant activity of the extracts, the substrate Thrombin Chromogenic substrate was used and extracts E1, E3, E5 and E7 showed greater inhibition of thrombin-like proteins in the venom. The second in order to investigate the anti-phospholipatic activity (anti PLA2) with the substrate 4N3OBA, and the extracts E1, E2, E3 and E6 were the most efficient in inhibiting PLA2 from the venom. And the last one to investigate the inhibitory activity of serine proteases with the substrate BAPNA and the extracts E1, E3, E4, E5 and E7 were able to inhibit the action of proteases. In this way, we were able to investigate a possible antivenom or complementary therapy action of extracts E1, E3, E4, E5 from M. floribundum .