Local and systemic toxicity of Echis carinatus venom: neutralization by Cassia auriculata L. leaf methanol extract.

Viper bites cause high morbidity and mortality especially in tropical and subtropical regions, affecting a large number of the rural population in these areas. Even though anti-venoms are available, in most cases they fail to tackle viper venom-induced local manifestations that persist even after anti-venom administration. Several studies have been reported the use of plant products and approved drugs along side anti-venom therapy for efficient management of local tissue damage. In this regard, the present study focuses on the protective efficacy of Cassia auriculata L. (Leguminosae) against Echis carinatus venom (ECV) induced toxicity. C. auriculata is a traditional medicinal plant, much valued in alternative medicine for its wide usage in ayurveda, naturopathy, and herbal therapy. Further, it has been used widely by traditional healers for treatment of snake and scorpion bites in the Western Ghats of Karnataka, India. In the present study, C. auriculata leaf methanol extract (CAME) significantly inhibited enzymatic activities of ECV proteases (96 ± 1 %; P = 0.001), PLA2 (45 ± 5 %; P = 0.01) and hyaluronidases (100 %; P = 0.0003) in vitro and hemorrhage, edema and myotoxicity in vivo. Further, CAME effectively reduced the lethal potency of ECV and increased the survival time of mice by ~6 times (17 vs 3 h). These inhibitory potentials of CAME towards hydrolytic enzymes, mortal and morbid symptoms of ECV toxins clearly substantiates the use by traditional healers of C. auriculata as a folk medicinal remedy for snakebite.