Neutralization of the edema-forming, defibrinating and coagulant effects of Bothrops asper venom by extracts of plants used by healers in Colombia

Abstract

We determined the neutralizing activity of 12 ethanolic extracts of plants against the edema-forming, defibrinating and coagulant effects of Bothrops asper venom in Swiss Webster mice. The material used consisted of the leaves and branches of Bixa orellana (Bixaceae), Ficus nymphaeifolia (Moraceae), Struthanthus orbicularis (Loranthaceae) and Gonzalagunia panamensis (Rubiaceae); the stem barks of Brownea rosademonte (Caesalpiniaceae) and Tabebuia rosea (Bignoniaceae); the whole plant of Pleopeltis percussa (Polypodiaceae) and Trichomanes elegans (Hymenophyllaceae); rhizomes of Renealmia alpinia (Zingiberaceae), Heliconia curtispatha (Heliconiaceae) and Dracontium croatii (Araceae), and the ripe fruit of Citrus limon (Rutaceae). After preincubation of varying amounts of each extract with either 1.0 µg venom for the edema-forming effect or 2.0 µg venom for the defibrinating effect, the mixture was injected subcutaneously (sc) into the right foot pad or intravenously into the tail, respectively, to groups of four mice (18-20 g). All extracts (6.2-200 µg/mouse) partially neutralized the edema-forming activity of venom in a dose-dependent manner (58-76% inhibition), with B. orellana, S. orbicularis, G. panamensis, B. rosademonte, and D. croatii showing the highest effect. Ten extracts (3.9-2000 µg/mouse) also showed 100% neutralizing ability against the defibrinating effect of venom, and nine prolonged the coagulation time induced by the venom. When the extracts were administered either before or after venom injection, the neutralization of the edema-forming effect was lower than 40% for all extracts, and none of them neutralized the defibrinating effect of venom. When they were administered in situ (sc at the same site 5 min after venom injection), the neutralization of edema increased for six extracts, reaching levels up to 64% for C. limon.

Ethnobotanic study of Randia aculeata (Rubiaceae) in Jamapa, Veracruz, Mexico, and its anti-snake venom effects on mouse tissue

“…On the other hand, only B. asper venom significantly diminished the number of platelets, reported in mice and in other human case reports (19). The current contribution shows that Randia aculeata protects against this event, which is why we infer that one of the plant's effects could be avoiding hemorrhages otherwise caused by snake venom, as has been demonstrated by employing other vegetal species (20)(21)(22)(23). It is also possible that this plant can partially neutralize myotoxic effects caused by some snake venoms, which are caused by phospholipase A 2 , metalloproteases and crotoxins (18,24).…”

Anatomia foliar de Tabebuia serratifolia (Vahl) Nich. (Bignoniaceae) propagadas in vitro, in vivo e durante a aclimatização

“…Várias espécies do gênero Tabebuia contêm na casca e no cerne do caule quantidades variáveis do lapachol e outras substâncias similares, dotadas de forte atividade bactericida (PARK et al, 2005), fungicida (PORTILLO et al, 2001), antiofídica (NÚÑEZ et al, 2004) e antitumoral (CHENNA et al, 2001).…”

Evaluation of anti-Bothrops asper venom activity of ethanolic extract of Brownea rosademonte leaves

“…Because of great similarity between B. asper and B. atrox venoms, the minimum inhibitory doses [minimum hemorrhagic dose (MHD), minimum coagulant dose (MCD), minimum indirect hemolytic dose (MIHD) and minimum proteolytic dose (MPD)] for each evaluated effect were determined based on the data previously reported for B. atrox venom (12)(13)(14)(15). For the experiments, we used the respective reported minimum inhibitory doses plus two high and two low levels of venom (3, 2, 1, 0.5 and 0.3 MIHD).…”

“…To evalu ate the neutralizing capacity of the plant extract against the coagulant effect of venom, one MCD (1.7 µg mL -1 ) of B. asper venom was dissolved in 50 µL PBS, pH 7.2, and preincubated at 37 °C for 30 min with the plant extract (100 or 200 µg) and then, the mixture was added to human plasma (0.3 mL) and preincubated at 37 °C. The time required for plasma coagulation was determined (15).…”