ABSTRACT
Abstract Snake envenomation is a public health problem, and while serum therapy prevents death, the local effects of venoms can lead to amputations or morbidities. Thus, alternative treatments deserve attention. In this study, we tested eight derivatives of 1,2,3-triazole against some toxic activities of Bothrops jararaca venom. The derivatives were synthesized, and their structures analyzed by infrared and nuclear magnetic resonance. After that, the ability of compounds to inhibit hemolysis, coagulation, proteolysis, hemorrhaging, edema, and lethal activities of B. jararaca venom was investigated. The derivatives were incubated with B. jararaca venom (incubation protocol), administered before (prevention protocol) or after (treatment protocol) injecting venom into the mice. Then, hemorrhaging assay occurred. As a result, most of the derivatives inhibited the activities, even if they were incubated, injected before or after B. jararaca venom. However, the derivatives TRI 07 and TRI 18 seemed to be the most efficient in impairing hemorrhaging. The derivatives showed a low drug score of toxicity based on an in silico technique. Therefore, the derivatives fulfilled physicochemical and biological requirements to become drugs, and they may be a brand new initiative for designing antivenom molecules to complement antivenom therapy to efficiently block tissue necrosis or any other local effects.
ABSTRACT
Abstract Background The five-paced pit viper (Deinagkistrodon acutus), endemic to China and northern Vietnam, is responsible for most snakebites in the Chinese territory. Antivenom produced from horses is the main treatment for snakebites, but it may cause numerous clinical side effects and have other disadvantages involved in their production such as the welfare of animals. The present study was conducted aiming to develop an alternative antibody (IgY) from the egg yolk of leghorn chickens immunized with snake venom. Methods IgY from the egg yolk of white leghorn chickens previously immunized intramuscularly with D. acutus venom was extracted by water, precipitated by ammonium sulfate and purified by affinity chromatographic system. IgY was identified by SDS-PAGE, ELISA and Western blot. Finally, IgY neutralization assays to test its efficacy against hemorrhagic, edema-forming and myotoxic activities of D. acutus venom were conducted on mice. Results For the first time, IgY antibodies against D. acutus venom were raised successfully in egg yolk of chickens injected with D. acutus venom multiple times. By three steps, including caprylic acid extraction, ammonium sulfate precipitation and affinity chromatography, IgY antibodies were isolated and purified from egg yolk, which exhibited a single protein band on SDS-PAGE and two bands (about 65 kDa and 35 kDa, respectively) under reducing conditions, and presented a high titer (1:40,000) tested by ELISA. Immunoblot analysis confirmed that these IgY were polyclonal antibodies since they bound to components of D. acutus venom. Furthermore, immunodiffusion assay showed that anti-D. acutus venom IgY cross-reacted with the venoms of Trimeresurus albolabris and D. saxatilis Emelianov, but did not react to the venoms of Bungarus multicinctus and Naja atra. In the neutralizing lethal assay, the median effective dose of anti-D. acutus venom IgY was 14.14 mg/kg of mouse body weight under the challenge dose (3 LD50 of D. acutus venom). In neutralizing the hemorrhagic, edema-forming and myotoxic activities of D. acutus venom, IgY showed the characteristic dose-dependent neutralization effects against all these toxic activities of D. acutus venom. Conclusion Anti-D. acutus venom IgY antibodies with high purity and titer were for the first time raised successfully in egg yolk of chickens immunized with D. acutus venom. They were effective in neutralizing the lethal effects, and the hemorrhagic, edema-forming and myotoxic acitivities of D. acutus venom. IgY could be an effective source to develop a treatment against snake bites in humans or animals in the future.
ABSTRACT
Background The five-paced pit viper (Deinagkistrodon acutus), endemic to China and northern Vietnam, is responsible for most snakebites in the Chinese territory. Antivenom produced from horses is the main treatment for snakebites, but it may cause numerous clinical side effects and have other disadvantages involved in their production such as the welfare of animals. The present study was conducted aiming to develop an alternative antibody (IgY) from the egg yolk of leghorn chickens immunized with snake venom. Methods IgY from the egg yolk of white leghorn chickens previously immunized intramuscularly with D. acutus venom was extracted by water, precipitated by ammonium sulfate and purified by affinity chromatographic system. IgY was identified by SDS-PAGE, ELISA and Western blot. Finally, IgY neutralization assays to test its efficacy against hemorrhagic, edema-forming and myotoxic activities of D. acutus venom were conducted on mice. Results For the first time, IgY antibodies against D. acutus venom were raised successfully in egg yolk of chickens injected with D. acutus venom multiple times. By three steps, including caprylic acid extraction, ammonium sulfate precipitation and affinity chromatography, IgY antibodies were isolated and purified from egg yolk, which exhibited a single protein band on SDS-PAGE and two bands (about 65 kDa and 35 kDa, respectively) under reducing conditions, and presented a high titer (1:40,000) tested by ELISA. Immunoblot analysis confirmed that these IgY were polyclonal antibodies since they bound to components of D. acutus venom. Furthermore, immunodiffusion assay showed that anti-D. acutus venom IgY cross-reacted with the venoms of Trimeresurus albolabris and D. saxatilis Emelianov, but did not react to the venoms of Bungarus multicinctus and Naja atra. In the neutralizing lethal assay, the median effective dose of anti-D. acutus venom IgY was 14.14 mg/kg of mouse body weight under the challenge dose (3 LD50 of D. acutus venom). In neutralizing the hemorrhagic, edema-forming and myotoxic activities of D. acutus venom, IgY showed the characteristic dose-dependent neutralization effects against all these toxic activities of D. acutus venom. Conclusion Anti-D. acutus venom IgY antibodies with high purity and titer were for the first time raised successfully in egg yolk of chickens immunized with D. acutus venom. They were effective in neutralizing the lethal effects, and the hemorrhagic, edema-forming and myotoxic acitivities of D. acutus venom. IgY could be an effective source to develop a treatment against snake bites in humans or animals in the future.(AU)
Subject(s)
Animals , Snake Venoms , Antivenins , Immunodiffusion , Crotalinae , Naja naja , AntibodiesABSTRACT
Several plant extracts rich in pharmacologically active compounds have shown to antagonize venom of several species. Mangifera indica has been used against snakebite by the traditional healers, However, there is paucity of scientific data in support. In this study, we evaluated the antivenom potential of aqueous extract of stem bark of M. indica against D. russellii venom-induced pharmacological effects such as life myotoxicity, edema, LD50 etc. The extract inhibited the phospholipase, protease, hyaluronidase, 5`nucleotidase, ATPase and alkaline phosphomonoesterase activities with varying IC50 values. It significantly inhibited both metalloproteases and serine proteases activities. Further, the extract significantly reduced the myotoxicity of the venom, as evident by the reduction of serum creatin kinase and lactate dehydrogenase activities. Though the extract completely inhibited in vitro PLA2 activity, it was unable to completely inhibit in situ hemolytic and in vivo edema-inducing activities, usually brought about by PLA2s. In lethality studies, co-injection of the venom preincubated with the extract showed higher protection than the independent injection of venom, followed by the extract in the mice. However, in both the cases the extract -a cocktail of inhibitors significantly increased the survival time, when compared to that of mice injected (i.p) with the venom alone. These results encourage further studies on the potential use of cocktail of inhibitors in improving the treatment of snake envenomation. Further, this study substantiates the use of M. indica as an antidote against snakebite by the traditional healers.