Antiprotease activity of indigenous medicinal plants against Pakistani Echis carinatus venom

Background: Snakebite is a commonly neglected tropical disease globally. According to the World Health Organization, tens of thousands of deaths have been reported due to the venomous snakes previously. Among such snakes, vipers of the genus Echis are extremely important clinically. In folk medicine, plants are commonly used for the treatment of snakebites even though snake venom antiserum is the only efficacious treatment currently known. Objectives: This study was conducted to investigate the inhibitory potential of extracts from Pakistani medicinal plants against protease enzyme abundant in Echis carinatus venom. Materials and Methods: Organic extracts from different indigenous plant species and parts were used for in vitro determination of their inhibition against protease activity in snake venom. Active methanolic extracts were further fractioned using different solvents, and these fractions were also tested for antiprotease activity. Results: Results of this study show that Calotropis procera (Wild.) R. Br., Matthiola incana (L.) R. Br., and Terminalia arjuna Wight and Arn were able to neutralize the protease enzyme by 63%, 71%, and 66%, respectively. Trichodesma indicum (L.) R. Br. showed 51% inhibition of protease activity. Conclusion: The present study indicated about C. procera (Wild.) R. Br., M. incana (L.) R. Br., and T. arjuna Wight and Arn possessed inhibitor (s) against protease enzyme present in E. carinatus venom and would be worthwhile for development as treatment against envenomation in future.