Blood chemistry of rats pretreated with Mucuna pruriens seed aqueous extract MP101UJ after Echis carinatus venom challenge

Histological, molecular and biochemical detection of renal injury after Echis pyramidum snake envenomation in rats

Nephrotoxicity is a common sign of snake envenomation. The present work aimed to clarify the effect of intraperitoneal injection of 1/8 LD50 and 1/4 LD50 doses of Echis pyramidum snake venom on the renal tissue of rats after 2, 4 and 6 h from envenomation. Histopathological examination showed intense dose and time dependent abnormalities, including swelling glomerulus and tubular necrosis and damage as well as signs of intertubular medullary hemorrhage at early stages of envenomation. However, at late stages of envenomation by any of the doses under investigation, no intact renal corpuscles were recorded and complete lysis in renal corpuscles with ruptured Bowman's capsules was observed. Immunohistochemistry by immunohistochemical staining was used to test the protein expression of Bax in renal tissue of rats. The result showed that the expression of Bax in renal tissue sections of envenomated rats was increased according to dose and time-dependant manner. The isolation of DNA from the renal cells of envenomed rats pointed out to the occurrence of DNA fragmentation, which is another indicator for renal tissue injury especially after 6 h of 1/4 LD50 of E. pyramidum envenomation. Oxidative stress biomarkers malondialdehyde and nitrite/nitrate levels, antioxidant parameters; glutathione, total antioxidant capacity and catalase were assayed in renal tissue homogenates. The venom induced significant increase in the levels of malondialdehyde and nitrite/nitrate while the levels of glutathione, total antioxidant capacity and catalase were significantly decreased, especially after 6 h of envenomation. The results revealed that the E. pyramidum induced dose and time-dependant significant disturbances in the physiological parameters in the kidney. We conclude that the use of the immunohistochemical techniques, the detection of DNA integrity and oxidative stress marker estimations are more specific tools that can clarify cellular injury and could point out to the defense activity of the renal tissue at envenomation.

A randomized ethnomedicinal survey of snakebite treatment in southwestern parts of Bangladesh

Snakebite is the single most important toxin-related injury, causing substantial mortality in many parts of the Africa, Asia and the Americas. Incidence of snakebite is usually recorded in young people engaged in active physical work in rural areas. The various plant parts used to treat snakebite included whole plant, leaves, barks, roots and seeds. Most bites in Bangladesh are recorded between May and October with highest number in June. Lower and upper limbs are most common sites of snakebite, but it may happen in other sites as well. Snake venom (蛇毒 shé dú) has been the cause of innumerable deaths worldwide. However, antiserum does not provide enough protection against venom induced hemorrhage, necrosis, nephrotoxicity and hypersensitivity reactions. Informed consent was obtained from the practitioners prior to interviews. After the survey, it is concluded that the medicinal plants used by tribal medicinal practitioners in Bangladesh for treatment against snakebite are Acyranthes aspera L. (土牛膝 tǔ niú xī), Amaranthus Viridis L. (野莧菜 yě xiàng cài), Asparagus racemosus Willd (總序天冬 zǒng xù tiān dōng) and Emblica officinalis Gaertn (油柑 yóu gān), while the non-tribal communities used 35 plant species among them, most of the plants reported as new species used against snakebite in the belonging family. The plants present a considerable potential for discovery of novel compounds with fewer side effects for treatment of antisnake venom and can, at least in Bangladesh, become a source of affordable and more easily available drugs.

Detoxification of Echis ocellatus venom-induced toxicity by Annona senegalensis Pers

Different fractions (I-V) of the methanolic leaf extracts of Annona senegalensis were assessed for their anti-snake venom activities. Fractions III neutralized lethal toxicity induced by Echis ocellatus venom and manifested the same potency as the crude extracts against the venom. The anti-snake venom activity of fraction III was clearly shown by the complete abrogation of venom-induced haemorrhage and the 75% record of surviving mice which were injected with a pre-incubate of venom and extract in the ratio 1:30 w/w after a 24 h. Also, fraction III exhibited a weak inhibitory effect on fibrinogen clotting activity of this venom. The key phytochemicals mediating the activity of this fraction are flavonoids and tannins. The detoxification of this venom by fraction III and the possible mode of action in the pathology of snake envenoming is discussed in this report.

Production of high titre antibody response against Russell's viper venom in mice immunized with ethanolic extract of fruits of Piper longum L. (Piperaceae) and piperine

Piper longum L. fruits have been traditionally used against snakebites in north-eastern and southern region of India. The aim of the study was to assess the production of antibody response against Russell's viper venom in mice after prophylactic immunization with ethanolic extract of fruits of Piper longum L. and piperine. The mice sera were tested for the presence of antibodies against Russell's viper venom by in vitro lethality neutralization assay and in vivo lethality neutralization assay. Polyvalent anti-snake venom serum (antivenom) manufactured by Haffkine Bio-Pharmaceutical Corporation Ltd. was used as standard. Further confirmation of presence of antibodies against the venom in sera of mice immunized with PLE and piperine was done using indirect enzyme-linked immunosorbent assay (ELISA) and double immunodiffusion test. Treatment with PLE-treated mice serum and piperine-treated mice serum was found to inhibit the lethal action of venom both in the in vitro lethality neutralization assay and in vivo lethality neutralization assay. ELISA testing indicated that there were significantly high (p<0.01) levels of cross reactions between the PLE and piperine treated mice serum and the venom antigens. In double immunodiffusion test, a white band was observed between the two wells of antigen and antibodies for both the PLE-treated and piperine-treated mice serum. Thus it can be concluded that immunization with ethanolic extract of fruits of Piper longum and piperine produced a high titre antibody response against Russell's viper venom in mice. The antibodies against PLE and piperine could be useful in antivenom therapy of Russell's viper bites. PLE and piperine may also have a potential interest in view of the development of antivenom formulations used as antidote against snake bites.

In vitro antiophidian properties of Dipteryx alata Vogel bark extracts

Extracts from Dipteryx alata bark obtained with different solvents (hexane, dichloromethane, ethyl acetate and methanol) were mixed in vitro with Bothrops jararacussu (Bjssu, 40 μg/mL) and Crotalus durissus terrificus (Cdt, 15 μg/mL) snake venoms, and applied to a mouse phrenic nerve-diaphragm preparation to evaluate the possible neutralization of venom effects. Cdt venom neurotoxic effect was not inhibited by any of the extracts, while the neurotoxic and myotoxic actions of Bjssu venom were decreased by the methanolic extract. This inhibition appears to be augmented by tannins. Dichloromethane bark extract inhibited ~40% of Bjssu venom effects and delayed blockade induced by Cdt. The methodology used to determine which extract was active allows inferring that: (i) phenolic acids and flavonoids contained in the methanolic extract plus tannins were responsible mostly for neutralization of Bjssu effects; (ii) terpenoids from the dichloromethane extract may participate in the anti-Cdt and anti-Bjssu venom effects; (iii) a given extract could not inhibit venoms from different species even if those belong to the same family, so it is improper to generalize a certain plant as antiophidian; (iv) different polarity extracts do not present the same inhibitory capability, thus demonstrating the need for characterizing both venom pharmacology and the phytochemistry of medicinal plant compounds.

Neutralization of local and systemic toxicity of Daboia russelii venom by Morus alba plant leaf extract

Antivenom therapy is the current best therapy available for the treatment of fatal snake envenomation. However, the antivenom offers less or no protection against local effects such as extensive edema, hemorrhage, dermo-, myonecrosis and inflammation at the envenomed region. Viperidae snakes are highly known for their violent local effects and such effects have been commonly treated with plant extracts without any scientific validation in rural India. In this investigation Morus alba plant leaf extract has been studied against the Indian Vipera/Daboia russelii venom induced local and systemic effects. The extract completely abolished the in vitro proteolytic and hyaluronolytic activities of the venom. Edema, hemorrhage and myonecrotic activities were also neutralized efficiently. In addition, the extract partially inhibited the pro-coagulant activity and completely abolished the degradation of Aalpha chain of human fibrinogen. Thus, the extract processes potent antisnake venom property, especially against the local and systemic effects of Daboia russelii venom.

Local tissue destruction and procoagulation properties of Echis carinatus venom: inhibition by Vitis vinifera seed methanol extract

Plant extracts are extensively used against snakebites in Indian folk medicine. In this study, one such traditionally used plant, Vitis vinifera L. (Vitaceae) seed methanol extract has been studied for its ability to neutralize Indian Echis carinatus (saw-scaled viper) venom. The extract effectively inhibited toxic effects, such as oedema, haemorrhage, myonecrosis and coagulation of citrated human plasma. Further, the extract inhibited the caseinolytic, hyaluronolytic and fibrinogenolytic activities of the venom. The extract caused dose dependent inhibition of the toxic activities studied, suggesting venom inhibition. Thus, the anti-snake venom property of the extract appears to be highly promising for further investigation in order to achieve better neutralization of Indian E. carinatus venom poisoning.

Proteomic analysis of the pathophysiological process involved in the antisnake venom effect of Mucuna pruriens extract

Previously, we reported the antisnake venom properties of a Mucuna pruriens seed extract (MPE) and tested its in vivo efficacy against Echis carinatus venom (EV) in short- (1 injection) and long-term (three weekly injections) treatments. The aim of the present study was to investigate plasma proteome changes associated with MPE treatments and identify proteins responsible for survival of envenomated mice (CHALLENGED mice). Six treatment groups were studied. Three control groups: one saline, one short-term and one long-term MPE treatment. One group received EV alone. Two test groups received EV with either a short-term or long-term MPE treatment (CHALLENGED mice). The plasma from each group was analysed by 2-DE/MALDI-TOF MS. The most significant changes with treatment were: albumin, haptoglobin, fibrinogen, serum amyloid A and serum amyloid P. Most of these changes were explained by EV effects on coagulation, inflammation and haemolysis. However, MPE treatments prevented the EV-induced elevation in HPT. Consequently, HPT levels were similar to controls in the plasma of CHALLENGED mice. The plasma of CHALLENGED mice showed substantial proteomic modifications. This suggests the mechanism of MPE protection involves the activation of counterbalancing processes to compensate for the imbalances caused by EV.

Screening of plants containing Naja naja siamensis cobra venom inhibitory activity using modified ELISA technique

Enzyme-linked immunosorbent assay (ELISA) has been modified for screening plants with antagonistic activity to Naja naja siamensis cobra venom. Aqueous extracts from plants were investigated for their inhibitory effects on the binding of anti-cobra venom antibody to antigen, cobra venom, fixed onto 96-well microtiter plates. Ingredients in extracts were allowed to react with immobilized venom before the subsequent addition of antivenom antibody. Venom components affected by exposure to the extracts, unable to interact with their specific antibody, were predicted to be unable to bind to their native destinations or natural receptors. Curcuma cf. zedoaria, an old Thai medicinal plant, showed clear inhibitory activity in the ELISA test. Neurotoxin and protein degradative enzymes, major components in venom, were identified as targets of this extract in Western immunoblotting analysis. Ingredients in the extract showed high affinity to the toxin in competition assay by immunoprecipitation. The extract attenuated toxin activity by extending contraction time of diaphragm muscle after envenomation and had a potency to protect cellular proteins from venom degradative enzymes. Curcuma parviflora, with less activity in ELISA, exhibited acceptable results in two experiments but negative results in two experiments, whereas Curcuma longa, having low activity in the ELISA test, never showed any favorable results. Screening of 36 samples could classify plants into an inhibition range of 0 to 86%. This modified ELISA is recommended as a preliminary screening method for inhibitors with a large number of samples.

Protection of Mucuna pruriens seeds against Echis carinatus venom is exerted through a multiform glycoprotein whose oligosaccharide chains are functional in this role

In a previous paper we demonstrated that extracts of Mucuna pruriens seeds (MPE) protect mice against Echis carinatus venom (EV) by an immunological mechanism. In this paper we demonstrate that the MPE immunogen generating the antibody that cross-reacts with the venom proteins is a multiform glycoprotein (gpMuc) whose immunogenic properties mainly reside in its glycan-chains. The glycoprotein was purified from the protein extract of M. pruriens seeds using Concanavalin A affinity chromatography. Using 2-D gel electrophoresis it separated into seven isoforms having MWs in the range from 20.3 to 28.7 kDa and pIs from 4.8 to 6.5. N-terminal sequencing of these spots revealed close similarity since all of them contained the consensus sequence DDREPV-DT found in soybean Kunitz-type trypsin inhibitor. We suggest that gpMuc contains both N- and O-glycans. Mild alkaline treatment but not PNGase F led to loss of reactivity, indicating that O-glycans are probably involved in the antigenicity of gpMuc.