RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE OF ANDROGRAPHIS PANICULATA: The whole plant (including leaves and roots) is used in traditional Ayurveda and Siddha medicine to treat various clinical conditions such as fever, respiratory tract infections, colic pain, liver disorders, diabetes, hypertension, and inflammation. It is also used as an antidote for snake-bite, poisonous bites of insects and recommended as a dietary supplement to boost immunity. AIM OF THE STUDY: In-vitro thromboelastographic evaluation of the efficacy of methanolic extract of Andrographis paniculata (MAP) and polyvalent anti-snake venom (ASV) in neutralizing the Naja naja (N.N) venom-induced changes in hemostatic parameters. MATERIALS AND METHODS: Thromboelastographic evaluation of hemostatic parameters was initiated by adding 3µg N.N venom to citrated whole blood from healthy volunteers. The effect of different concentrations of ASV and MAP in neutralizing the toxicity of N.N venom were studied in two groups. In group 1 experiments, citrated whole blood (340µl) was mixed with N.N venom (3µg), immediately followed by successive addition of ASV (5µl, 8µl and 15µl) or MAP (15µg, 30µg, 60µg and 120 µg) or combination of ASV and MAP (3µl ASV+30µg MAP and 3µl ASV+60µg MAP). In group 2 experiments, N.N venom was incubated with whole blood for 90 minutes at 37°C, followed by successive addition of ASV (5µl, 10µl, and 15µl) or MAP (30µg and 60µg) or combination of ASV and MAP (5µl ASV+30µg MAP and 5µl ASV+60µg MAP). RESULT: In Group 1 experiments, N.N venom caused significant (p<0.05) increase in R-time, K-time, LY30% and a decrease in angle and MA. Optimum effect on hemostatic parameters was observed at a concentration of 8µl ASV, where all the deleterious effects of the venom were completely reversed. Similarly, the addition of MAP to the assay system could reproduce results as ASV, in reversing the deleterious effects of the venom. This occurred in a concentration-dependent manner, from 15µg-60µg, with the optimum results at 60µg. When ASV concentration was reduced to 3µl and supplemented with MAP (30µg or 60µg), the positive supplementary effect of MAP was demonstrated. In Group 2 experiments, N.N venom caused significant (p<0.05) changes in all TEG parameters, with most deleterious changes observed in MA and LY30% compared to Group 1 experiments. ASV when added in increasing concentrations (5-15µl), had beneficial effects only on K-time, angle, and MA. When added together with ASV, MAP (30µg or 60µg) could significantly (p<0.05) supplement the effect of ASV (5µl) in improving R-time, K-time, and angle. CONCLUSION: This in-vitro study demonstrates the effectiveness of MAP as a supplement to ASV in combating the deleterious effects of N.N venom on hemostasis. However, further in-vivo experiments in animal models are required to substantiate these effects.