Neutralising ability of Terminalia fagifolia extract (Combretaceae) against the in vitro neuromuscular effects of Bothrops jararacussu venom

Abstract

The ability of Terminalia fagifolia hydroalcoholic extract (Tf-HE) to neutralise the paralysis and myotoxicity induced by Bothrops jararacussu venom was assayed using mouse phrenic nerve-diaphragm (PND) preparation and two varieties of chick biventer cervicis (BC) preparations. Tf-HE 100 μg/mL and 500 μg/mL were tested against 40 and 200 μg of venom/mL in PND and BC preparations, respectively, using pre- and post-venom incubation treatments. The effects of Tf-HE against the myotoxicity caused by venom were evaluated via histological analysis (PND) and creatine kinase (CK) release (BC). Tf-HE was able to reverse the venom paralysis in both preparation types. The contractures to exogenous ACh in BC preparations showed that Tf-HE may act on extrinsic, preserving those intrinsic postsynaptic receptors. There was a positive correlation between CK and morphological changes. The high non-hemolytic saponin content can explain the Tf-HE efficacy against the toxic effects of B. jararacussu venom in vertebrate neuromuscular preparations.

The Influence of Silver Nanoparticles Against Toxic Effects of Philodryas olfersii Venom

“…It also can be interpreted that the venom had minor access to both intrinsic/junctional (elicited by indirect stimulation) and extrinsic/extra junctional (elicited in absence of electrical stimulation face to exogenous ACh addition) postsynaptic nicotine receptors. 35 , 36 , 45 , 46 The addition of KCl, which directly depolarizes the tissue resulting in muscle contracture, is widely used in Biventer cervicis preparation to evidence the presence of compounds that affects the muscle membrane potential; 47 a reduction of KCl-induced contracture is indicative of myotoxic damage to tissue. 48 The results in the present study are consistent with the findings of myotoxins in the Philodryas olfersii Duvernoy’s gland secretion, 49 and myotoxic effects seen in experimental models, 21 , 23 , 25 , 50 including in human accidents (edema, erythema, ecchymosis, regional lymphadenopathy, neurotoxic and myotoxic effects, but without coagulative disorders).…”

“…Chicks were euthanized via inhalation overdose of isoflurane (BioChimico ® , Rio de Janeiro, RJ, Brazil) and the biventer cervicis muscles were removed according to Ginsborg & Warriner 34 as described elsewhere. 35 Briefly, the preparation was mounted under a tension of 1 g per 0.5 cm in a 5 mL organ bath (Panlab ® Four Chamber Organ Bath) maintained at 37°C, aerated with carbogen (95% O 2 and 5% CO 2 ), and kept in a Krebs solution with the following composition (mM, pH 7.5): NaCl, 118.1; KCl, 4.8; CaCl 2 , 2.5; MgSO 4 , 1.2; NaHCO 3 , 25; and glucose 11.1. A bipolar platinum ring electrode was inserted around the tendon within which the nerve trunk supplying the muscle runs.…”