Venom

This investigation understands the interaction between lyophilized crude Viper snake venom () and Silver nanoparticles (SNPs) using biophysical and biochemical approaches. SNPs were synthesized by chemical reduction method and characterized using UV-Visible spectroscopy, Dynamic Light Scattering (DLS) and Transmission electron microscope (TEM). The average hydrodynamic size of SNPs was found to be 52 nm with 0.261 PDI. TEM image revealed the spherical shape of SNP. Interaction of SNPs and viper venom was resulted in the formation of complex which was confirmed by using DLS technique. Spectroscopic results showed an increase in absorbance intensity of venom upon interaction with SNPs which indicated interaction with venom proteins. Fluorescence spectroscopic data revealed the quenching in the fluorescence intensity of viper venom upon incubation with varying concentration of SNPs. The results obtained by biochemical assays (Protease and whole blood clotting test) revealed the inhibit...

BACKGROUND: Serpente das Montanhas da Etiópia (Bitis parviocula) é um viperídeo conhecido somente em poucas localizações do sudoeste da Etiópia. MÉTODOS: Um total de 30 µg de veneno de B. arietans e B. parviocula foram corridos em gel de 10 a 20% de tricina. Para se estabelecer a quinquagésima dose de letalidade (LD50) foram usados cinco grupos de oito camundongos para cada veneno. A atividade hemorrágica para o veneno cru foi testada. A atividade fibrogenolítica do veneno cru foi medida usando 2,5 mg/mL de solução de fibrinogênio e 0,03 mg/mL de veneno cru. A atividade de gelatinase do veneno foi testada em um filme KODAK X-OMATTM. Venenos crus de B. parviocula e B. arietans foram testados no que diz respeito à sua capacidade de afetar o tempo de coagulação, a velocidade de coagulação e a função plaquetogênica em sangue humano total. RESULTADO: o antiveneno SAIMR foi confirmado neste estudo no que diz respeito à neutralização da atividade letal do veneno de Bitis parviocula. ED50s do antiveneno SAIMR sobre a B. parviocula e B. arietans neutralizou metade de 18,2 e 66,7 mg respectivamente do veneno. As atividades hemorrágicas (MHDs) de B. parviocula e B. arietans foram respectivamente 0,88 e 1,7 µg. Os venenos de B. arietans e B. parviocula degradaram cadeias α e β em tempos diferentes. A cadeia Γ permaneceu não afetada. O veneno da B. parviocula não mostrou atividade de gelatinase, enquanto o de B. arietans teve um MGD de 6,9 µg. A nível de 3 mg/mL os venenos crus de B. parviocula e B. arietans não afetaram significantemente o tempo e a velocidade de coagulação. CONCLUSÕES: O antiveneno SAIMR é bastante efetivo para neutralizar o veneno da B. parviocula e deveria ser considerado para o tratamento de envenenamentos por estas serpentes.

In South Asia, the "Big-4" venomous snakes Naja naja, Bungarus caeruleus, Daboia russelii, and Echis carinatus are so-called because they are the most medically important snakes in the region. Antivenom is the only effective treatment option for snakebite envenoming but antivenom is not produced domestically in Pakistan making the country reliant on polyvalent products imported from India and Saudi Arabia. The present study investigated the toxin composition and activity of the venoms of Pakistani specimens by means of proteomic and physio/phar-macological experiments. To evaluate the composition of venoms, 1D/2D-PAGE of crude venoms and RP-HPLC followed by SDS-PAGE were performed. Enzymatic, hemolytic, coagulant and platelet aggregating activities of crude venoms were assayed and were concordant with expectations based on the abundance of protein species in each. Neutralization assays were performed using Bharat polyvalent antivenom (BPAV), a product raised against venoms from Big-4 specimens from southern India. BPAV exhibited cross-reactivity against the Pakistani venoms, however, neutralization of clinically relevant activities was variable and rarely complete. Cumulatively, the presented data not only highlight geographical variations present in the venoms of the Big-4 snakes of South Asia, but also demonstrate the neutralization potential of Indian polyvalent against the venom of Pakistani specimens. Given the partial neutralization observed, it is clear that whilst BPAV is a life-saving product in Pakistan, in future it is hoped that a region-specific product might be manufactured domestically, using venoms of local snakes in the immunising mixture.

The piercing-sucking mouthparts of the true bugs (Insecta: Hemiptera: Heteroptera) have allowed diversification from a plant-feeding ancestor into a wide range of trophic strategies that include predation and blood-feeding. Crucial to the success of each of these strategies is the injection of venom. Here we review the current state of knowledge with regard to heteropteran venoms. Predaceous species produce venoms that induce rapid paralysis and liquefaction. These venoms are powerfully insecticidal, and may cause paralysis or death when injected into vertebrates. Disulfide-rich peptides, bioactive phospholipids, small molecules such as N,N-dimethylaniline and 1,2,5-trithiepane, and toxic enzymes such as phospholipase A 2 , have been reported in predatory venoms. However, the detailed composition and molecular targets of predatory venoms are largely unknown. In contrast, recent research into blood-feeding heteropterans has revealed the structure and function of many protein and non-protein components that facilitate acquisition of blood meals. Blood-feeding venoms lack paralytic or liquefying activity but instead are cocktails of pharmacological modulators that disable the host haemostatic systems simultaneously at multiple points. The multiple ways venom is used by heteropterans suggests that further study will reveal heteropteran venom components with a wide range of bioactivities that may be recruited for use as bioinsecticides, human therapeutics, and pharmacological tools.

Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an 'antivenomics' approach, the ability of a polyspecifi c (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are not included in the immunization mixture. In addition, the neutralization of lethal, hemorrhagic, myotoxic, coagulant, proteinase and phospholipase A 2 (PLA 2 ) activities of these venoms by the antivenom was assessed. The antivenom was highlyeffective in immunodepleting many venom components, particularly high molecular mass P-III metalloproteinases (SVMPs), L-amino acid oxidases, and some serine proteinases and P-I SVMPs. In contrast, PLA 2 s, certain serine proteinases and P-I SVMPs, and a C type lectin-like protein were only partially immunodepleted, and two PLA 2 molecules were not depleted at all. The antivenom was able to neutralize all toxic and enzymatic activities tested, although neutralization of lethality by A. nummifer venom was achieved when a challenge dose of 3 LD 50 s of venom was used, but was iffective when 4 LD 50 s were used. These results, and previously obtained evidence on the immunoreactivity of this antivenom towards homologous and heterologous venoms, revealed the low immunogenicity of a number of venom components (PLA 2 s, CRISPs, P-I SVMPs, and some serine proteinases), underscoring the need to search for innovative immunization protocols to improve the immune response to these antigens.

The venom proteomes of Toxicocalamus longissimus and Hydrophis cyanocinctus, a fossorial and a marine species, respectively, of the Hydrophiinae genus of Elapidae, were investigated by Edman degradation of RP-HPLC isolated proteins, and de novo MS/MS sequencing of in-gel derived tryptic peptide ions. The toxin arsenal of T. longissimus is made up of 1-2 type-I PLA 2 molecules, which account for 6.5% of the venom proteins, a minor PIII-SVMP (1.4% of the venom toxins), and~20 members of the 3FTx family comprising 92% of the venom proteome.

Heparin, in some regions of Brazil has been used in the treatment of bothropic accidents, but the data found in the literature are inconclusive about its effectiveness. The venoms of Bothrops atrox and of B. erythromelas were characterized according to their biological activities. The capacity of heparin in neutralizing these activities was tested with doses of 3 and 6 IU in isolated form and associated to Antibothropic Serum (ABS). It was verified that heparin, in doses of 3 and 6 IU, was not effective in neutralizing the desfibrinating and edema-forming activities of B. atrox venom and the hemorrhagic and coagulant actions of both venoms. Heparin diminished the effectiveness of the ABS in the neutralization of the hemorrhagic and edema-forming activities of the B. atrox venom. However, heparin in the 6 IU dose was capable of neutralize the edema-forming of the B. erythromelas and increase the effectiveness of the ABS. Heparin also neutralized the phospholipasic A2 activity of B. a...

Hymenoptera stings are a health concern. Apidae (bees), Vespidae (hornets, yellow jackets and wasps) and Formicidae (ants) are medically-important stinging insects under the order Hymenoptera. Clinical features from simple skin manifestations to severe and fatal organ injury are due to the hypersensitivity reactions and/ or the toxic effects of the venom inoculated. Here we discuss on Hymenoptera stings involving apids (honey bees) and vespids (wasps, hornets and yellow jackets) and their effect on renal function and associated morphological changes in the kidney. Despite the differences in venom composition and quantity released per sting in two insect groups, both lead to similar medical consequences, such as localised normal allergic reactions, mild to severe anaphylaxis and shock and multiple organ and tissue injury leading to multiple organ failure. Acute kidney injury (AKI) is one of the unusual complications of Hymenoptera stings and has the basis of both immune-mediated and toxic effects. Evidence has proven that supportive therapy along with the standard medication is very efficient in completely restoring the kidney function without any recurrence.

This study describes the effects of Bothrops marajoensis venom (Marajó lancehead) on isolated neuromuscular preparations of chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND). At low concentrations (1µg/ml for CBC and 5µg/ml for PND), the venom exhibited a neuromuscular blocking without any damaging effect on the muscle integrity. At higher concentration (20μg/ml for PND), together with the neuromuscular blockade, there was a moderate myonecrosis. The results show differences between mammalian and avian preparations in response to venom concentration; the avian preparation was more sensitive to venom neurotoxic effect than the mammalian preparation. The possible presynaptic mechanism underlying the neuromuscular blocking effect was reinforced by the observed increase in MEPPs at the same time (at 15min) when the facilitation of twitch tension occurred. These results indicate that the B. marajoensis venom produced neuromuscular blockade, which appeared to be presynaptic at low concentrations with a postsynaptic component at high concentrations, leading to muscle oedema. These observations demand the fractionation of the crude venom and characterization of its active components for a better understanding of its biological dynamics.

21 22 42 highlight the dominant role of positive selection in the evolution of these proteins. 43 Conspicuously many of the proteins identified in the proteome were found to be homologous 44 to proteins with known activities affecting vasodilation and platelet aggregation. We show 45 that vampire bat venom proteins possibly evade host immune response by the mutation of the 56 Keywords: 57 Molecular evolution 58 Vampire bat 59 Venom 60 Positive selection 61 Desmodus rotundus 62 J O U R N A L O F P R O T E O M I C S X X ( 2 0 1 3 ) X X X -X X X 48 venoms but also provide a rich resource for novel lead compounds for use in drug design 49 and development. 50 51 Biological significance 52 These results have direct implications in understanding the molecular evolutionary history 53 of vampire bat venom. The unusual peptides discovered reinforce the value of studying 54 such neglected taxon for biodiscovery.

Mouse P19 embryonic carcinoma (EC) cells are pluripotent and can differentiate into a population consisting largely of neurons and glia cells using a concentration of 5x10(-7)M of retinoic acid (RA). Thus, P19 EC cells are a good model system to study events occurring during the critical phases of neuronal differentiation, in vitro. Honey bee venom (BV) consists of mellitin, phospholipase A2, apamin and several other bioactive substances. Previous studies have shown that mellitin and phospholipase A2 - two major components of BV - play an important role in the differentiation of neurons. The purpose of this study was to examine effects of BV and RA on the differentiation of cholinergic neuron in P19 cell line. Preliminary results obtained from morphological examination showed that six days after treatment with 5x10(-7)M RA, P19 cells produced processes, and gradually obtained neuronal phenotype at approximately day-10. All cells then died at day-11. P19 cells treated with 1.3μg/ml B...

The frequency of mass bee attacks has dramatically increased in the Americas following the introduction and spread of the aggressive Africanized 'killer' bee (Apis mellifera scutellata). As yet no specific therapy is available, which led us to develop an ovine Fab-based antivenom as a potential new treatment. Sera from sheep immunized against the venom contained high levels of specific antibodies, as demonstrated by ELISA and by small-scale affinity chromatography, against both whole (A. m. mellifera) venom and purified melittin. A nerve muscle preparation was used to show the myotoxic effects of the venom and neutralization by the antivenom. Antivenom neutralizing ability was also demonstrated using assays for venom phospholipase A2 and in vivo activities. Venom from both European and Africanized bees appeared identical when analyzed by acid-urea gel electrophoresis. This antivenom may therefore provide the first specific therapy for the treatment of mass envenomation by either European or Africanized 'killer' bees.

The mortality related to snake bites is an extreme public health problem because the estimated death prevalence per year is about 1,25,000 globally. Insufficient health services, bad transportation and consequent delay in synthetic anti-snake venom management are the main motives for excessive mortality. Adverse drug reactions and inadequate storage conditions limit the use of synthetic anti-snake venom. The medicinal flora, available domestically and used widely by traditional healers, consequently need attention. Most of the snake bite cases are typically undermined due to loss of proper consciousness of the mass people. However, present evaluation has been focused at the artificial and traditional herbs and their anti-venom property, which can be a venturing stone in setting up the future treatment against snake bite treatment and management.

Hemiscorpius lepturus (H. lepturus) is one of the most dangerous scorpions in Iran. Intramuscular administration (IM) of available Razi antivenom to H. lepturus venom is used by many of Iranian clinicians. The purpose of the current study was to investigate the efficiency of IM route for treatment of envenomed patients by H. lepturus. We compared the pharmacokinetics parameters of venom and antivenom via subcutaneous (SC) and IM administration, respectively. The blood samples were taken at various predetermined time intervals, i.e., 10, 40, 60, 180, 210, 360 and 400min following 5μg (131)I-labeled venom and 5, 10, 40, 120 and 360min following 0.2ml of (131)I-labeled antivenom administration. The radio-iodination was carried out using the chloramin-T method. The results showed that pharmacokinetic parameters of the venom were T(elimination half-life) = 103.25min; Vd/F (apparent volume of distribution) = 14.9ml/kg; Cl/F (total blood clearance) = 0.04ml/kg/min; mean resident residual t...

Venom phospholipases A2 (PLA(2)) are associated with neurotoxic, myotoxic, cardiotoxic, platelet aggregation, and edema activities. A PLA(2) (Drs-PLA(2)) was purified from Daboia russelii siamensis venom by a two-step purification procedure consisting of size-exclusion, followed by anion exchange high performance liquid chromatography (HPLC). The molecular weight of the Drs-PLA(2) was 13,679Da, which was determined by MALDI-TOF mass spectrometry. Its N-terminal amino acid sequence was homologous to basic PLA(2)s of viperid snake venoms. The Drs-PLA(2) had indirect hemolytic and anticoagulant activities, cytotoxic activity with a CC(50) of 65.8nM, and inhibited SK-MEL-28 cell migration with an IC(50) of 25.6nM. In addition, the Drs-PLA(2) inhibited the colonization of B16F10 cells in lungs of BALB/c mice by ∼65%.

Venom from male and female specimens of the medically important Venezuelan scorpion Tityus nororientalis have been compared. Males showed a significantly higher venom yield (2.39mg/individual) compared to female scorpions (0.98mg/individual). Female venom was significantly more toxic than that of males, with a median lethal dose (LD(50)) in C57BL/6 mice of 9.46 μg venom protein/gm body weight [95% confidence interval (8.91-9.94)] whereas LD(50) for males was 13.36(12.58-14.03) μg/gm. Mass spectral analyses by MALDI-TOF revealed differences in venom composition between males and females. From a clinical standpoint, the time course of toxicity course indicated a tendency, in the case of the female venom, to elicit the earlier occurrence of severe signs such as sialorrhea, dyspnea (bradypnea/apnea) and exophthalmus particularly in the late toxicity phase. Female venom was significantly less efficient than male venom to inhibit the binding of anti-T. discrepans antibodies to immobilized...

Mass spectrometry a b s t r a c t Milked venoms of Conus demonstrate direct lineage to US Food and Drug Administration approved and present in-trial drug leads. Yet the complexity of the milked venom has not been adequately investigated or characterized, in a sustainable manner. In this study we determine the extent of molecular mass differentiation in milked venom from captive Conus magus and confirm the expression of known conotoxin constituents. We demonstrate the presence of post-translational N-terminal peptide truncation, which differentiates the milked venom constituent a-conotoxin MI from the novel a-conotoxin MIC. This truncation has a direct effect on peptide bioactivity -K i of 89.1 AE 9.1 and 248.7 AE 10.9 nM (a-conotoxin MI and MIC respectively) toward the muscle-type nAChR (Torpedo). These milked venom conotoxins demonstrated acute lethality in fish, with a LD 50 of 12.24 and 23.29 mg kg À1 for a-conotoxin MI and MIC respectively. By synthesizing and investigating the synthetic intermediate variant des[Gly] 1 a-conotoxin MI, it was demonstrated that retention of the N-terminal arginine residue increased affinity at the muscle-type nAChR site (binding K i of 73.3 AE 5.8 nM and lethal toxicity level LD 50 of 8.19 mg kg À1 ). This posttranslational modification event within the milked venom of C. magus represents a unique mechanism by which cone snails are able to increase the chemical and pharmacological diversity of their venoms.

We document inadequately diagnosed coagulopathy (potential to be life threatening) due to Ovophis monticola bite. Although its bites are common in the hills of Nepal, associated envenomations have not been documented elaborately. Herein, we present the clinical and treatment details of a proven O. monticola bite and areas where it may pose the risk of envenomations (suggesting huge populations in Asia to be vulnerable to its bites). Its envenomation was managed symptomatically with several non-evidence-based interventions. Since no specific pitviper antivenom is available in Nepal yet, managing coagulopathy associated to O. monticola envenomation is still challenging. This case emphasizes the need of developing the standard protocol for the diagnosis and management of pitviper bites and study of effectiveness of the available pitviper antivenoms until specific pitviper antivenom is available. Further, the demonstrated distribution localities of this species may have implications for...

We report a novel hybrid, molecular and elemental mass spectrometry (MS) setup for the absolute quantification of snake venom proteomes shown here for two desert black cobra species within the genus Walterinnesia, Walterinnesia aegyptia and Walterinnesia morgani. The experimental design includes the decomplexation of the venom samples by reverse-phase chromatography independently coupled to four mass spectrometry systems: the combined bottom-up and top-down molecular MS for protein identification and a parallel reverse-phase microbore high-performance liquid chromatograph (RP-μHPLC) on-line to inductively coupled plasma (ICP-MS/MS) elemental mass spectrometry and electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QToF MS). This allows to continuously record the absolute sulfur concentration throughout the chromatogram and assign it to the parent venom proteins separated in the RP-μHPLC-ESI-QToF parallel run via mass profiling. The results provide a locus-resolved and quantitative insight into the three desert black cobra venom proteome samples. They also validate the units of measure of our snake venomics strategy for the relative quantification of snake venom proteomes as % of total venom peptide bonds as a proxy for the % by weight of the venom toxins/toxin families. In a more general context, our work may pave the way for broader applications of hybrid elemental/molecular MS setups in diverse areas of proteomics. KEYWORDS: snake venomics, combined top-down and bottom-up venomics, hybrid elemental and molecular mass spectrometry, absolute quantification of venom proteome, desert black cobra, Walterinnesia aegyptia, Walterinnesia morgani

Unlike other venomous predators, the parasitoid wasp Ampulex compressa incapacitates its prey, the cockroach Periplaneta americana, to provide a fresh food supply for its offspring. We first established that the wasp larval development, from egg laying to pupation, lasts about 8 days during which the cockroach must remain alive but immobile. To this end, the wasp injects a cocktail of neurotoxins to manipulate the behavior of the cockroach. The cocktail is injected directly into the head ganglia using biosensors located on the stinger. The head sting induces first 30 min of intense grooming followed by hypokinesia during which the cockroach is unable to generate an escape response. In addition, stung cockroaches survive longer, lose less water, and consume less oxygen. Dopamine contained in the venom appears to be responsible for inducing grooming behavior. For the hypokinesia, our hypothesis is that the injected venom affects neurons located in the head ganglia, which send descending tonic input to bioaminergic neurons. These, in turn, control the thoracic premotor circuitry for locomotion. We show that the activity of identified octopaminergic neurons from the thoracic ganglia is altered in stung animals. The alteration in the octopaminergic neurons' activity could be one of the mechanisms by which the venom modulates the escape circuit in the cockroach's central nervous system and metabolism in the peripheral system.

The venom of the “armed” spider Phoneutria nigriventer comprises several potent toxins. One of the most toxic components from this venom is the neurotoxin PnTx2-6 (LD50 = ∼ 0.7 μg/mouse, 48 residues, five disulfide bridges, MW = 5,289.31 Da), which slows down the inactivation of various Na+ channels. In mice and rats, this toxin causes priapism, an involuntary and painful erection, similar to what is observed in humans bitten by P. nigriventer. While not completely elucidated, it is clear that PnTx2-6 potentiates erectile function via NO/cGMP signaling, but it has many off-target effects. Seeking to obtain a simpler and less toxic molecule able to retain the pharmacological properties of this toxin, we designed and synthesized the peptide PnPP-19 (19 residues, MW = 2,485.6 Da), representing a discontinuous epitope of PnTx2-6. This synthetic peptide also potentiates erectile function via NO/cGMP, but it does not target Na+ channels, and therefore, it displays nontoxic properties in a...

There is limited information on antivenom pharmacokinetics. This study aimed to investigate the pharmacokinetics of an Indian snake antivenom in humans with Russell's viper bites. Patient data and serial blood samples were collected from patients with Russell's viper (Daboia russelii) envenoming in Sri Lanka. All patients received Indian F(ab')2 snake antivenom manufactured by VINS Bioproducts Ltd. Antivenom concentrations were measured with sandwich enzyme immunoassays. Timed antivenom concentrations were analysed using MONOLIXvs4.2. One, two and three compartment models with zero order input and first order elimination kinetics were assessed. Models were parameterized with clearance(CL), intercompartmental clearance(Q), central compartment volume(V) and peripheral compartment volume(VP). Between-subject-variability (BSV) on relative bioavailability (F) was included to account for dose variations. Covariates effects (age, sex, weight, antivenom batch, pre-antivenom conc...

Venom research is a highly multidisciplinary field that involves multiple subfields of biology, informatics, pharmacology, medicine, and other areas. These different research facets are often technologically challenging and pursued by different teams lacking connection with each other. This lack of coordination hampers the full development of venom investigation and applications. The COST Action CA19144–European Venom Network was recently launched to promote synergistic interactions among different stakeholders and foster venom research at the European level.

Toxicología Neutralización heteróloga e interacción de amanitinas con venenos de Bothrops y Crotalus y de abeja Heterologous neutralization and interaction of toxic amanitins with Bothrops and Crotalus venoms, and honey bee venom Neutralização heteróloga e interação das amanitinas tóxicas com veneno de Bothrops e Crotalus e veneno de abelha

Sea anemone venoms are rich reservoirs of biologically active proteins which include actinoporins, a large family of lethal pore-forming 20 kDa polypeptides. In this study, venom isolated from leathery sebae anemone Heteractis crispa, was examined for presence of actinoporins and its potential to be used as a substitute for commercial cell lysis buffers. Proteome profiling of the venom extract using SDS-PAGE and silver staining revealed proteins with molecular weights 20-215 kDa, indicating the presence of 20 kDa actinoporins among its active proteins. The venom extract was tested for functionality as a stand-alone cell lysis reagent or as a complement to established cell lysis solutions. Heteractis crispa venom when used with sodium dodecyl sulfate and proteinase K, demonstrated efficient isolation of highly pure DNA. The isolated nucleic acid samples were run in 1% (w/v) agarose gel and confirmed the absence of nuclease activity throughout all treatments. Taken together, venom isolated from H. crispa with detergent and protease additives, was found to be a viable alternative cell lysis reagent used in isolating undamaged genomic DNA with high purity.

Echis carinatus (Saw-scale viper) is one of the most venomous snakes in Asia and some parts of the Africa with deadly hemotoxic venom. It has been reported that suramin, an antitrypansomiasis drug, can inhibits the toxic effects of some snake venoms. This study was conducted to evaluate the antagonistic effects of suramin against the venom of the Iranian snake Echis carinatus. Adult albino mice weighing 35±5g were divided into nine groups (A

Although some venoms and their isolated compounds have been shown to have antibacterial properties, most have not been investigated for such activity. Echis carinatus is one of the most venomous snakes in the world and has an effective haematotoxic venom that destroys endothelial cells and causes haemorrhagia. In this study, the antibacterial activity of Iranian snake Echis carinatus venom against six different bacteria (Staphylococcus aureus, Methicillin Resistant Staphylococcus aureus (MRSA), Listeria monocytogenes, Bacillus subtilis, Salmonella typhimurium and Escherichia coli O157:H7), were investigated. Crude venom (100µg/ml) and different standard antibiotic disks as positive controls were tested by the gel diffusion method. Since the results showed that Echis carinatus venom has a significant antibacterial effect against S. aureus and MRSA, the minimum inhibitory concentrations (MIC) were also determined for these two susceptible bacteria: this was 80µg ml-1 against both stra...

The rates at which venomous animals produce venoms are of obvious biological and medical importance, but factors influencing those rates remain poorly understood. We gathered data on venom yield (wet mass of venom) and percentage solids (dry mass of the venom divided by wet mass) for 53 eastern brownsnakes (Pseudonaja textilis) and 36 mainland tigersnakes (Notechis scutatus) over a 4-year period at Venom Supplies Pty. Ltd, a commercial venom production facility in South Australia. Tigersnakes yielded about threefold more venom (by wet mass) than brownsnakes, but with slightly lower percentage solids. Both species showed significant geographic variation in percentage solids. Venom yields varied as a function of the snake's sex and geographic origin, but these effects were secondary consequences of geographic and sex-based differences in body size. Relative head size affected venom yield in brownsnakes but not tigersnakes. Overall, the amount of venom that a snake produced during milking was affected by its species, its geographic origin, its body size and relative head size, and by the time of year that it was milked, as well as by interactions among these factors. Body size was the most important effect on venom yield, with yields increasing more rapidly with size in brownsnakes than in tigersnakes. Research at the intersection of snake ecology and venom characteristics has great potential, but will require a genuinely interdisciplinary approach.

Snakebite envenomation affects thousands of people annually in Nepal. Published hospital-based studies of snakebite treatment in Nepal are scarce. Here we present the results of the first prospective, cross-sectional study of hospitalized envenomed snakebite cases in southcentral Nepal, a region characterized by poor pre-hospital care of snakebites, limited supply and excessive use of antivenom, and a high case/fatality ratio. We seek to identify clinical management problems and suggest potential interventions to improve treatment of snakebites. Out of the 342 patients presented with snakebites to an urban emergency department in the Terai region of Nepal between April and September of 2007, 39 patients were enrolled based on development of ptosis or swelling of bitten body parts. We collected patient demographic information and documented circumstances of snakebite, prehospital care, hospital care, and development of complications. Among 39 envenomated patients admitted to Bharatpu...

Venom from male and female specimens of the medically important Venezuelan scorpion Tityus nororientalis have been compared. Males showed a significantly higher venom yield (2.39mg/individual) compared to female scorpions (0.98mg/individual). Female venom was significantly more toxic than that of males, with a median lethal dose (LD(50)) in C57BL/6 mice of 9.46 μg venom protein/gm body weight [95% confidence interval (8.91-9.94)] whereas LD(50) for males was 13.36(12.58-14.03) μg/gm. Mass spectral analyses by MALDI-TOF revealed differences in venom composition between males and females. From a clinical standpoint, the time course of toxicity course indicated a tendency, in the case of the female venom, to elicit the earlier occurrence of severe signs such as sialorrhea, dyspnea (bradypnea/apnea) and exophthalmus particularly in the late toxicity phase. Female venom was significantly less efficient than male venom to inhibit the binding of anti-T. discrepans antibodies to immobilized...

Background: Scorpion stings are responsible for many deaths in humans; however, the toxicity mechanisms of the venoms from many species are not well studied. We investigated the cardiotoxicity of the crude venom from H. lepturus scorpion and its isolated fractions, F-I to F-VI.
Methods: The scorpion’s venom was extracted into six fractions by chromotagraphy. Healthy male Wistar rats (N=72) were equally divided into eight groups of nine: G1: Controls (0.5ml. normal saline), G2: Crude venom (1000µg/kg), G3: F-I (120µg/kg), G4: F-II (430µg/kg), G5: F-III (80 µg/kg), G6: F-IV (180µg/kg), G7: F-V (60µg/kg), and G8: F-VI (130µg/kg). Blood samples were obtained by cardiac puncture at 1, 3 and 24 hours after the venom injection. The serum levels of AST, LDH, CPK, CK-MB and troponin-I were determined. Upon euthanasia, the hearts were removed from the rats and examined microscopically for histopathology.
Results: In groups receiving crude venom and F-VI, we observed multifocal fragmentation of myocardial fibers, hemorrhage, degeneration and disappearance of striations in cardiac muscles as compared to the controls. The findings showed that AST and LDH activity in groups 2, 4 and 8, CPK activity in groups 2, 4, 6 and 8 and CK-MB activity and troponin-I levels in groups 2 and 8 increased significantly compared to those in the control group.
Conclusion: There was evidence of significant cardiotoxicity in the group receiving crude venom and F-VI. Although alterations in the enzymatic and troponin-I levels were observed in other groups, the greatest cardiotoxicity of H. lepturus venom was caused by fraction VI.

Hemiscorpius lepturus (H. lepturus) is one of the most dangerous scorpions in Iran. Intramuscular administration (IM) of available Razi antivenom to H. lepturus venom is used by many of Iranian clinicians. The purpose of the current study was to investigate the efficiency of IM route for treatment of envenomed patients by H. lepturus. We compared the pharmacokinetics parameters of venom and antivenom via subcutaneous (SC) and IM administration, respectively. The blood samples were taken at various predetermined time intervals, i.e., 10, 40, 60, 180, 210, 360 and 400min following 5μg (131)I-labeled venom and 5, 10, 40, 120 and 360min following 0.2ml of (131)I-labeled antivenom administration. The radio-iodination was carried out using the chloramin-T method. The results showed that pharmacokinetic parameters of the venom were T(elimination half-life) = 103.25min; Vd/F (apparent volume of distribution) = 14.9ml/kg; Cl/F (total blood clearance) = 0.04ml/kg/min; mean resident residual t...

The venomous sea anemone Phyllodiscus semoni causes cases of severe stinging. We isolated Phyllodiscus semoni toxin 20A (PsTX-20A), a hemolytic and lethal polypeptide (20 kDa), from the nematocyst venom of this species for theˆrst time. Furthermore, we sequenced the cDNA encoding PsTX-20A. The deduced amino acid sequence of PsTX-20A showed that this toxin was a new member of the actinoporin family, which consists of several cytolytic polypeptides originating from sea anemones. PsTX-20A showed lethal toxicity to the shrimp Palaemon paucidens when administered via intraperitoneal injection (LD 50 , 50 mg W kg) and hemolytic activity toward 0.8% sheep red blood cells (ED 50 , 80 ng W ml).

Viperbite is often associated with severe local toxicity, including progressive hemorrhage and myotoxicity, persistent even after the administration of anti-snake venom (ASV). In the recent past, investigations have revealed the orchestrated actions of Zn2+ metalloproteases (Zn2+MPs), phospholipase A2s (PLA2s) and hyaluronidases (HYs) in the onset and progression of local toxicity from the bitten site. As a consequence, venom researchers and medical practitioners are in deliberate quest of potent molecules alongside ASV to tackle the brutal local manifestations induced by aforesaid venom toxins. Based on these facts, we have demonstrated the protective efficacy of inhibitor cocktail containing equal ratios of N,N,N',N'-tetrakis (2-pyridylmethyl) ethane-1,2-diamine (TPEN) and silymarin (SLN) against progressive local toxicity induced by Echis carinatus venom (ECV). In our previous study we have shown the inhibitory potentials of TPEN towards Zn2+MPs of ECV (IC50: 6.7 μM). In ...

Spider venom contains a mixture of peptide toxins, some able to kill insects specifically to those considered as important pest. In this study, a peptide toxin produced by the Macrothele gigas spider, Magi 6, was cloned and expressed in tobacco plants, as this toxin has been shown to constitute an effective insecticide. For this purpose, a genetic construction for the cDNA that codifies for Magi 6 was subcloned in a plant expression vector using the 35S promoter and the 5 0-end leader from tobacco mosaic virus, in order to transform tobacco leaf disks. The resulting plants demonstrated the presence of Magi 6 gene in the tobacco genome using PCR, and transcription of the cDNA was verified by means of RT-PCR. The expression of the Magi 6 peptide in tobacco was demonstrated by Western blot, which exhibited the expected size, thus suggesting a correct processing of the signal peptide. No morphological alterations in the different transgenic lines were observed, nor any change in plant growth. Subsequently, experiments were carried out challenging detached leaves or whole plants with the herbivorous insect Spodoptera frugiperda. The bioassays indicated that the transgenic lines were significantly more resistant than the wild type plants. This work demonstrated that the expression of Magi 6 peptide in transgenic plants conferred resistance to insect attack and opens the possibility of employing this peptide to improve the resistance of diverse plants.

Scorpaena plumieri venomous fish inflicted severe injuries in humans characterized by systemic effects and cardiovascular abnormalities. Although cardiotoxic and hypotensive effects induced in rats by this venom have been studied, little is known about their effect on bronchial epithelial permeability and airway inflammation in mice. The primary goal of this study was to determine whether the intraplantar or intraperitoneal injection of S. plumieri venom results in systemic response, and whether this event initiates acute lung injury. We found that BALB/c mice developed neutrophilic infiltrates, areas of lung hemorrhage and alveolar macrophage activation within 24 h after injection with S. plumieri venom. These histopathological changes were associated with an early increase in BAL fluid protein and early induction of cytokines, chemokines and matrix metaloproteinases, followed by a later increase in BAL fluid neutrophils. These findings provide clear evidence that the injection of S. plumieri venom in footpad or peritoneal cavity of mice results in venom deposition in the airway and initiates a sustained inflammatory response in the lungs.

The Scorpion’s venom considered to be highly complex mixture of nucleotides, enzymes, mucoproteins, biogenic amines, salts, as well as peptides and proteins, which have been used in traditional medicine for thousands of years mainly in Asia and Africa. With the significant discoveries in the number of valuable biologically active components of scorpion venom, numerous drug candidates have been found with the potential to encounter many of the emerging global health crisis. This mini-review sheds light on the application of scorpion venoms and toxins as potential novel antibacterial, antifungal and antiviral, especially as anticancer therapeutics.

Background: Up to 50% of patients with stinging-insect allergy have double-positive RAST results to honeybee and yellow jacket (YJ) venom. True double sensitization and crossreactivity through venom hyaluronidases are considered main reasons for this multiple reactivity. Objective: We investigated the role of antibodies against crossreactive carbohydrate determinants in venom double positivity. Methods: CAP inhibition experiments were performed with crude oilseed rape (OSR) and timothy grass pollen extracts and a neoglycoprotein construct displaying a MUXF glycan, as present in pineapple-stem bromelain (MUXF-BSA). CAP to OSR was used as a rough measure for carbohydrate-specific IgE in individual sera. Results: CAP results to OSR pollen were positive in 2 of 14 single-positive honeybee venom sera, 2 of 16 single-positive YJ venom sera, and 33 (80.5%) of 41 double-positive sera (P < .00001, χ 2 test). CAP inhibition was performed in 16 selected patients with a CAP class of 3 or higher to both venoms. In 9 of 11 patients with a highly positive CAP result to OSR (CAP score to OSR > CAP score to second venom), pollen extracts, MUXF-BSA, or both were able to completely inhibit IgE binding to one of the venoms, whereas this was not the case in 5 patients with a negative or weakly positive CAP result to OSR (CAP score to OSR < CAP score to second venom). Conclusions: The data suggest that carbohydrate-specific IgE is a major cause for the double positivity to honeybee and YJ venom seen in patients with Hymenoptera allergy. Because these antibodies may have low clinical relevance, they may severely impede the correct diagnosis of Hymenoptera venom allergy. (

Secretory phospholipases A2 (sPLA2s) play an important role in the generation of inflammatory events in several human diseases. Secretory PLA2s obtained from snake venoms have been widely used as pharmacological tools to elucidate the physiopathology of inflammatory conditions, as well as to reproduce the clinical manifestations of human envenomation by snake venoms. In venoms from Bothrops genus, two main types of sPLA2s have been characterized, namely, the catalytically active Asp-49 enzymes and the catalytically inactive variants Lys-49, that present Lys instead of Asp at position 49. Injections of Asp-49 and Lys-49 sPLA2 variants into experimental animals evoke classical inflammatory events such as local edema formation and leukocyte recruitment. Additionally, Lys-49 and the Asp-49 sPLA2s induce mechanical hyperalgesia and allodynia in rodent models. An array of endogenous agents such as histamine, 5-hydroxytryptamine (5-HT), bradykinin, tachykinins, arachidonic acid metabolites, pro-inflammatory cytokines, and nitric oxide (NO) have been implicated in sPLA2-induced responses. The catalytic activity and/or the cationic content of sPLA2 has been proposed to be of great importance in triggering S.K.P. Costa Department of Pharmacology, Institute of Biomedical Sciences (ICB), University of São Paulo (USP), São Paulo, SP, Brazil e-mail: [email protected] E.A. Camargo Department of Physiology, Center of Biological and Health Sciences, Federal University of Sergipe (UFS), São Cristóvão, SE, Brazil e-mail: [email protected] E. Antunes (*) Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, São Paulo, SP, Brazil e-mail: [email protected]; [email protected] # Springer Science+Business Media Dordrecht 2015 P. Gopalakrishnakone et al. (eds.), Toxins and Drug Discovery, Toxinology, DOI 10.1007/978-94-007-6726-3_10-1 1 its edematogenic, cell infiltrating, and pain responses. Venom Subscript&gt;/Subscript&gt; has also been used to mimic the clinical findings of acute pancreatitis associated with abdominal hyperalgesia. Bradykinin, substance P, and nitric oxide (NO) play important roles in pancreatic and remote lung inflammation during sPLA2-induced pancreatitis. This chapter summarizes the current knowledge on the local inflammatory mechanisms of venom sPLA2 in rodent models. The ability of venom sPLA2s to induce acute pancreatitis and underlying mechanisms will also be presented here.