Potential of a Herbal Preparation Used in Indigenous Medicine to Neutralize Nba nojo Venom: Example from Wet Zone, Sri Lanka

Abstract

The venom neutralizing ability of a herbal preparation used in traditional medicine was characterized. The preparation is known for successful treatment of Naj a naj a and Daboia russelii envenomation, particularly in the wet zone of the country, according to indigenous knowledge. The venom toxicity of Naja naja was evaluated using a 5-day-old chicken embryo model (n=3). Preliminary venom neutralizing ability of the herbal preparation was investigated with application of Naja naja venom preincubated with the herbal preparation on the vitellinevein of the chick, for a period of 6 hours. Pre-incubation of venom with the herbal preparation prevented the appearance of pathophysiological symptoms in the embryo and the death within the 6 hours as compared to the control, where the venom was pre-incubated with saline water. The results indicated the ability of the herbal preparation to neutralize Naja naja venom toxin. The venom Phospholipase Az (PLA2) activity, a common toxin known to exist in snake venoms, was also evaluated by measuring the amount of sodium hydroxide required to neutralize fatty acids liberated from egg yolk lecithin within 30 min. In the presence of the herbal preparation, PLAz activity of Naja naja venom was significantly reduced from 0.029mMmin ' to 0.018mMmin '. The herbal preparation was also shown to facilitate the blood coagulating toxicity of Naja naja venom. In the SDS gel electrophoresis analysis of the Naja naja venom, the herbal preparation and the mixture indicated proteolysis of some venom proteins by the herbal preparation. This appeared to be specific for venom proteins in the molecular weight range 28kD-98kD, which is possibly representing Phosphodiesterase, Acetylcholinesterase and Metalloproteases in the venom. The Naja naj a venom neutralizing property of the herbal preparation is therefore suggestive to be caused through PLAz inhibition and /or through the digestion of certoin protein families in the venoms