Neutralization of the neuromuscular activity of bothropstoxin-i, a myotoxin from Bothrops jararacussu snake venom, by a hydroalcoholic extract of Casearia sylvestris Sw. (guaçatonga)

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: Y. Oshima-Franco, C. M. V. Alves, N. Andréo Filho, M. Gerenutti, A. C. O. Cintra, G. B. Leite, L. Rodrigues-Simioni, M. G. Silva
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2005
• Subjects: alternative medicine; phytotherapy; plant extracts; snakebite; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1590/S1678-91992005000400007; https://doaj.org/article/9b5c19c2cde44efda676f81d741220b2

Numerous plants are used as snakebite antidotes in Brazilian folk medicine, including Casearia sylvestris Swartz, popularly known as guaçatonga. In this study, we examined the action of a hydroalcoholic extract from C. sylvestris on the neuromuscular blockade caused by bothropstoxin-I (BthTX-I), a myotoxin from Bothrops jararacussu venom, in mouse isolated phrenic nerve-diaphragm (PND) preparations. Aqueous (8 and 12 mg/ml, n=4 and 5, respectively) and hydroalcoholic (12 mg/ml, n=12) extracts of the leaves of C. sylvestris caused facilitation in PND preparations followed by partial neuromuscular blockade. BthTX-I (20 µg/ml, n=4) caused 50% paralysis after 65±15 min (mean ± S.E.M). Preincubation (30 min at 37° C) of BthTX-I (20 µg/ml, n=4) with a concentration of the hydroalcoholic extract (4 mg/ml) that had no neuromuscular activity, such as the control (n=5), prevented the neuromuscular blockade caused by the toxin. This protection may be mediated by compounds such as flavonoids and phenols identified by thin-layer chromatography and colorimetric assays.