Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus
Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.
presentation patterns and treatments offered for snake bites at Kitui District Hospital, and to characterize the causative venomous snakes. Patients and methods. This was a prospective case series carried out over a period of 8 months. Patients presenting at the hospital with snake bites were included in the study. A pre set.
Eight different species of non-venomous snakes of the Colubridae family, and three different species of poisonous snakes of the Viperidae family are native in Slovenia. In the period between 1999 and October of 2008, 39 snake bites were reported to the Poison Control Centre. The most common clinical findings in snake bite victims are discernible fang marks, rapidly progressive swelling, pain, ecchymosis, lymphangitis, and regional lymphadenitis. Systemic signs of envenomation can be delayed a...
Background Snake bites are a neglected public health issue in poor rural communities, and the true burden of snake bites is not known. Kitui County has a high incidence of snake bites and no functional snake bite control programs exists. Diagnostic tests for snake species identification are not available and management ...
Full Text Available Snakebites can present local or systemic envenomation, while neurotoxicity and respiratory paralysis are the main cause of death. The mainstay of management is anti-snake venom (ASV, which is highly effective, but liable to cause severe adverse reactions including anaphylaxis. The types of adverse reaction to polyvalent anti-snake venom have not been previously studied in Bangladesh. In this prospective observational study carried out between 1999 and 2001, in the Snake Bite Study Clinic of Chittagong Medical College Hospital, 35 neurotoxic-snake-bite patients who had received polyvalent anti-snake venom were included while the ones sensitized to different antitoxins and suffering from atopy were excluded. The common neurotoxic features were ptosis (100%, external ophthalmoplegia (94.2%, dysphagia (77.1%, dysphonia (68.5% and broken neck sign (80%. The percentage of anti-snake venom reaction cases was 88.57%; pyrogenic reaction was 80.64%; and anaphylaxis was 64.51%. The common features of anaphylaxis were urticaria (80%; vomiting and wheezing (40%; and angioedema (10%. The anti-snake venom reaction was treated mainly with adrenaline for anaphylaxis and paracetamol suppository in pyrogenic reactions. The average recovery time was 4.5 hours. Due to the danger of reactions the anti-snake venom should not be withheld from a snakebite victim when indicated and appropriate guidelines should be followed for its administration.
Silveria, P V; Nishioka, S de A
A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii). In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming). The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%), in the 10-19 years age group (26;29%), in the lower limbs (51/74;69%), between 6 A. M. and 2 P.M. (49;61%) and in the month of April (16;18%). One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.
Warrell, David A
Snake bite is a common and frequently devastating environmental and occupational disease, especially in rural areas of tropical developing countries. Its public health importance has been largely ignored by medical science. Snake venoms are rich in protein and peptide toxins that have specificity for a wide range of tissue receptors, making them clinically challenging and scientifically fascinating, especially for drug design. Although the full burden of human suffering attributable to snake bite remains obscure, hundreds of thousands of people are known to be envenomed and tens of thousands are killed or maimed by snakes every year. Preventive efforts should be aimed towards education of affected communities to use proper footwear and to reduce the risk of contact with snakes to a minimum through understanding of snakes' behaviour. To treat envenoming, the production and clinical use of antivenom must be improved. Increased collaboration between clinicians, epidemiologists, and laboratory toxinologists should enhance the understanding and treatment of envenoming. Copyright 2010 Elsevier Ltd. All rights reserved.
Peterson, Michael E
North American coral snakes are distinctively colored beginning with a black snout and an alternating pattern of black, yellow, and red. They have fixed front fangs and a poorly developed system for venom delivery, requiring a chewing action to inject the venom. The severity of a coral snake bite is related to the volume of venom injected and the size of the victim. The length of the snake correlates positively with the snakes venom yield. Coral snake venom is primarily neurotoxic with little local tissue reaction or pain at the bite site. The net effect of the neurotoxins is a curare like syndrome. In canine victims there have been reports of marked hemolysis with severe anemia and hemoglobinuria. The onset of clinical signs may be delayed for as much as 10 to 18 hours. The victim begins to have alterations in mental status and develops generalized weakness and muscle fasciculations. Progression to paralysis of the limbs and respiratory muscles then follows. The best flied response to coral snake envenomation is rapid transport to a veterinary medical facility capable of 24 hour critical care and assisted ventilation. First aid treatment advocated in Australia for Elapid bites is the immediate use of a compression bandage. The victim should be hospitalized for a minimum of 48 hours for continuous monitoring. The only definitive treatment for coral snake envenomation is the administration of antivenin (M. fulvius). Once clinical signs of coral snake envenomation become manifest they progress with alarming rapidity and are difficult to reverse. If antivenin is not available or if its administration is delayed, supportive care includes respiratory support. Assisted mechanical ventilation can be used but may have to be employed for up to 48 to 72 hours.
... bites by any of the following: Cobra Copperhead Coral snake Cottonmouth (water moccasin) Rattlesnake Various snakes found at ... Swelling Thirst Tiredness Tissue damage Weakness Weak pulse Coral snake bites may be painless at first. Major symptoms ...
Suntrarachun, S; Pakmanee, N; Tirawatnapong, T; Chanhome, L; Sitprija, V
A PCR technique was used in this study to identify and distinguish monocellate cobra snake bites using snake venoms and swab specimens from snake bite-sites in mice from bites by other common Thai snakes. The sequences of nucleotide primers were selected for the cobrotoxin-encoding gene from the Chinese cobra (Naja atra) since the sequences of monocellate cobra (Naja kaouthia) venom are still unknown. However, the 113-bp fragment of cDNA of the cobrotoxin-encoding gene was detected in the monocellate cobra venom using RT-PCR. This gene was not found in the venoms of Ophiophagus hannah (king cobra), Bungarus fasciatus (banded krait), Daboia russelii siamensis (Siamese Russell's Viper, and Calloselasma rhodostoma (Malayan pit viper). Moreover, direct PCR could detect a 665-bp fragment of the cobrotoxin-encoding gene in the monocellate cobra venom but not the other snake venoms. Likewise, this gene was only observed in swab specimens from cobra snake bite-sites in mice. This is the first report demonstrating the ability of PCR to detect the cobrotoxin-encoding gene from snake venoms and swab specimens. Further studies are required for identification of this and other snakes from the bite-sites on human skin.
Barker, Sarah; Charlton, Nathan P; Holstege, Christopher P
To evaluate the accuracy of Internet information regarding the prehospital care of venomous snake bites. Two major search engines were used to identify 48 Web sites regarding 6 prehospital treatment options for snake bite (removal of constrictive devices, ice, heat, electric shock, incision, and suction). Web sites were evaluated for their quality using the Health on the Net (HON) seal and Journal of the American Medical Association (JAMA) benchmarks. Of the 48 Web sites reviewed, 26 (54.1%) contained inappropriate recommendations. The remaining 22 Web sites were appropriate regarding all modalities addressed. Among the Web sites reviewed, inappropriate treatment recommendations included: suction (14); ice (6); incision (4); electric shock (1). Five Web sites that met all 4 JAMA benchmarks and the HON seal included 3 inappropriate treatment recommendations. Conversely, the 5 Web sites that met none of the JAMA benchmarks nor included the HON seal included only 2 inappropriate treatment measures. This study highlights the variety of misinformation available on the Internet regarding prehospital care of snake bites, and the unreliability of the HON seal and JAMA benchmarks as markers of accuracy. As the Internet becomes an increasing source of medical information for both the public and clinicians, the importance of accurate Web sites becomes imperative. Clinicians and lay people should be aware of the high variability of Internet information regarding snake bite prehospital care. Copyright © 2010 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Full Text Available Snakebite is an environmental hazard associated with significant morbidity and mortality. We report a case series of venomous snakebites in a military operational area of north India. Of 33 cases of snake bites presenting to the military hospital, 21 patients were envenomated. The median age of patients was 24 years; all were men. All of the envenomations were neurotoxic in nature. Abdominal pain (91%, headache (86%, dysphagia (86%, ptosis (77%, diplopia (72%, blurred vision (72%, dyspnea (67%, and vomiting (62% were the predominant clinical presentation. Polyvalent AntiSnakeVenom (ASV [mean 180 ml; range 90-320 ml] was given to all patients with systemic manifestations, and repeated as needed. Eleven (52% patients received neostigmine with glycopyrrolate to counter cholinergic effects. Two patients were given ventilatory support. The average time of recovery from envenomation was 16 hours after administration of ASV. All patients recovered without sequelae. Soldiers during military exercise are vulnerable to snakebites. Neurotoxic snakebites predominate in our study and usually present with autonomic features along with headache, abdominal pain, ptosis, diplopia and dysphasia. Preventive measures to minimize snake bites and planned treatment regimens should be emphasized among medical and military personnel deployed in the field operations.
Habib, A G; Gebi, U I; Onyemelukwe, G C
Four families of venomous snakes are found in Nigeria--Viperidae, Elapidae, Colubridae and Actraspididae but three species carpet viper (Echis ocellatus), black-necked spitting cobra (Naja nigricollis) and puff adder (Bitis arietans), belonging to the first two families, are the most important snakes associated with envenoming in Nigeria. The incidence of bites has been reported as 497 per 100,000 population per year with a 12 percent natural mortality, with Echis ocellatus accounting for at least 66 percent in certain foci. Bites occur more often while victims were farming, herding or walking although the spitting cobra may bite victims who roll upon it in their sleep. Carpet viper venom contains a prothrombin activating procoagulant, haemorrhagin and cytolytic fractions which cause haemorrhage, incoagulable blood, shock and local reactions/ necrosis. The spitting cobra bite manifests with local tissue reaction and occassionally with bleeding from the site of bite, but no classic neurotoxic feature has been observed except following Egyptian cobra (N. haje) bites. Cardiotoxicity and renal failure may occassionally occur following bites by the carpet viper and the puff adder. In the laboratory, haematological and other features are noted and immunodiagnosis has a role in species identification. Immobilisation of the bitten limb is probably the single most important first aid measure. Antivenom should be used cautiously when indicated. As only 8.5 percent of snake bite victims attend hospitals in Nigeria, health education should be the main preventive measure, mean-while, the study of immunisation of occupationally predisposed individuals in endemic areas should be intensified. A new Fab fragment antivenom specific to Nigerian Echis ocellatus was investigated clinically, just as the local herbs-Aristolochia spp, Guiera spp and Schummaniophyton spp are investigated experimentally.
Yañez-Arenas, Carlos; Yañez-Arenas, Arturo; Martínez-Ortíz, Daly
No information has been yet published on the epidemiological panorama of snakebite in the state of Yucatan. The aim of this study was to evaluate the geographic and temporal patterns of this problem in the state. Snakebite data was obtained from the Program of Zoonosis of the Health Services of Yucatan between 2003 and 2012. A total of 821 snakebite cases and an incidence of 41.9 accidents/100,000 inhabitants were recorded during this period. The annual average cases and incidence were 82.1 and 4.1 (bites/100,000 inhabitants), respectively. The highest number of snakebites occurred in 2005, while in 2003 the lowest number was recorded. Geographically, we observed a great disparity between municipalities, some of them reaching very high levels of incidence. This geographical variation may reflect the distribution and abundance of venomous snakes on one hand, and human population densities and their activities on the other. This study will help health authorities to know preliminarily the magnitude of snakebites in Yucatan and improving strategies to mitigate it.
Theakston, R D; Reid, H A; Larrick, J W; Kaplan, J; Yost, J A
Serum samples from 223 Waorani Indians, a tribe in eastern Ecuador, were investigated by enzyme-linked immunosorbent assay for antibodies to snake venom. Seventy-eight per cent were positive, confirming the highest incidence and mortality from snake bite poisoning yet recorded in the world. Most samples were positive for more than one venom antibody. Antibodies were found to venoms of Bothrops viper in 60% of positive cases, of Micrurus coral snake in 21%, and of the bushmaster, Lachesis muta, in 18%. Further studies are needed to determine whether high venom-antibody levels afford protection against further snake envenoming.
Interpretation & conclusions: In this preliminary study, it was found that the national ASV protocol was as effective as the conventional regimen for neurotoxic snake bites. However, the findings need to be tested in a larger randomized controlled trial for definitive conclusions.
Full Text Available Akira Sugamata, Naoki Yoshizawa, Takahiro OkadaDepartment of Plastic and Reconstructive Surgery, Tokyo Medical University Hachioji Medical Center, Tokyo, JapanAbstract: Gloydius blomhoffii, commonly known as Japanese mamushi, is a venomous viper species found widely in Japan. The most frequently bitten regions are the fingers and toes, and severe swelling causes compression of peripheral arteries and/or compartment syndrome of the extremities. We experienced four cases of mamushi bites to the hand, and undertook relaxation incision in the hands of three of these patients. As a result, the patients who underwent relaxation incision did not show any skin necrosis or permanent sensory disturbance in the affected fingers. Relaxation incision can be useful to not only decompress subcutaneous and compartment pressure of the hand, but also to wash out the venom from the bitten region by improving venous and lymphatic drainage.Keywords: mamushi, snakebite, viper, relaxation incision
Snake is one of the major group of games feared by people in many localities because of their venoms, yet snakes are equally afraid of human beings. This balance of terror apart from affecting both man and snakes has also led to their deaths. Epidemiology of snake bites among selected communities in the enclave of ...
Theakston, R D
Enzyme-linked immunosorbent assay (ELISA) is a very important tool for studying both the epidemiology and clinical effects of snake bite in man. For epidemiology ELISA depends on the development and persistence of specific humoral venom antibody in previous snake bite victims. In the Nigerian savanna 63% of previous bite victims possessed specific venom antibodies against Echis carinatus venom; in Ecuador, where there is a 5% annual mortality due to snake bite in a population of Waorani Indians, venom antibodies against a wide range of different venoms were identified in previous bite victims using ELISA. In certain areas it is often not possible, using the symptoms of envenoming, to determine which species of snake has bitten the patient. Field studies using ELISA in Nigeria and Thailand have been successful in establishing the species responsible for envenoming. Current studies are in progress on the development of a rapid immunoassay which should be capable of detecting the biting species within 5-10 min of sampling from the admission patient. This will be useful for the clinician as it will enable the rapid detection of the species responsible for envenoming and, therefore, the use of the correct antivenom. Experimental work on the development of new methods of antivenom production includes immunization of experimental animals with venom/liposome preparations, the preparation of venom antigens using monoclonal antibodies on affinity columns, and recombinant deoxyribonucleic acid technology. Liposomal immunization requires only a single injection of venom to obtain a rapid, high level and protective immune response. Venom liposomes may also be given orally resulting in a serum immunoglobulin G immune response in experimental animals. Use of such a system may eventually result in immunization of man in areas of high snake bite incidence and mortality.
.... The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite...
... gov/news/fullstory_166748.html Strike Back Against Snake Bites Expert advice on what to do if ... News) -- With summer comes a higher risk of snake bites, but emergency doctors have some advice on ...
Paulis, Melad G; Faheem, Ayman L
Snake bites are common in many regions of the world. Snake envenomation is relatively uncommon in Egypt; such unfortunate events usually attract much publicity. Snake bite is almost only accidental, occurring in urban areas and desert. Few cases were reported to commit suicide by snake. Homicidal snake poisoning is so rare. It was known in ancient world by executing capital punishment by throwing the victim into a pit full of snakes. Another way was to ask the victim to put his hand inside a small basket harboring a deadly snake. Killing a victim by direct snake bite is so rare. There was one reported case where an old couple was killed by snake bite. Here is the first reported case of killing three children by snake bite. It appeared that the diagnosis of such cases is so difficult and depended mainly on the circumstantial evidences. © 2015 American Academy of Forensic Sciences.
Gâz Florea Şerban Andrei
Full Text Available As more data are generated from proteome and transcriptome analysis revealing that metalloproteinases represent most of the Viperid and Colubrid venom components authors decided to describe in a short review a classification and some of the multiple activities of snake venom metalloproteinases. SVMPs are classified in three major classes (P-I, P-II and P-III classes based on the presence of various domain structures and according to their domain organization. Furthermore, P-II and P-III classes were separated in subclasses based on distinctive post-translational modifications. SVMPs are synthesized in a latent form, being activated through a Cys-switch mechanism similar to matrix metalloproteinases. Most of the metalloproteinases of the snake venom are responsible for the hemorrhagic events but also have fibrinogenolytic activity, poses apoptotic activity, activate blood coagulation factor II and X, inhibit platelet aggregation, demonstrating that SVMPs have multiple functions in addition to well-known hemorrhagic function.
Laustsen, Andreas Hougaard
Synergism between venom toxins exists for a range of snake species. Synergism can be derived from both intermolecular interactions and supramolecular interactions between venom components, and can be the result of toxins targeting the same protein, biochemical pathway or physiological process. Few...... simple systematic tools and methods for determining the presence of synergism exist, but include co-administration of venom components and assessment of Accumulated Toxicity Scores. A better understanding of how to investigate synergism in snake venoms may help unravel strategies for developing novel...
Snake bite is a significant public health problem in rural areas of many parts of the world1. Venomous snakes are found worldwide, except for a few islands and the frozen environments. Snake bite most commonly affects those living in the tropical and sub-tropical areas of Africa, Asia, the. Americas and Oceania.
Vonk, Freek Jacobus
in this thesis I have shown that snakes have undergone multiple changes in their genome and embryonic development that has provided them with the variation to which natural selection could act. This thesis provides evidence for the variable mechanisms of venom gene evolution, which presumably is
Sasaki, Jun; Khalil, Paul A; Chegondi, Madhuradhar; Raszynski, Andre; Meyer, Keith G; Totapally, Balagangadhar R
North America is home to 2 families of venomous snakes, Crotalinae (pit viper family) and Elapidae (coral snake family). Although there are several published reports describing and reviewing the management of pit viper snakebites in children, there are no recent similar publications detailing the clinical course and management of coral snake envenomation. Our case series describes the hospital course of children with coral snake bites admitted to our regional pediatric intensive care. We also reviewed prior published case reports of coral snake bites in the United States. We identified 4 patients with either confirmed or suspected coral snake envenomation from our hospital's records. In 2 cases, the snakebite occurred after apparent provocation. Antivenom was administered to 3 patients. The regional venom response team was consulted for management advice and supplied the antivenom. One patient had a prolonged hospital course, which was complicated by respiratory failure, bulbar palsy, and ataxia. All survived to discharge. Admission to pediatric intensive care is warranted after all Eastern coral snake bites. A specialized regional or national venom response team can be a useful resource for management advice and as a source of antivenom.
Markland, Francis S; Swenson, Stephen
Recent proteomic analyses of snake venoms show that metalloproteinases represent major components in most of the Crotalid and Viperid venoms. In this chapter we discuss the multiple activities of the SVMPs. In addition to hemorrhagic activity, members of the SVMP family also have fibrin(ogen)olytic activity, act as prothrombin activators, activate blood coagulation factor X, possess apoptotic activity, inhibit platelet aggregation, are pro-inflammatory and inactivate blood serine proteinase inhibitors. Clearly the SVMPs have multiple functions in addition to their well-known hemorrhagic activity. The realization that there are structural variations in the SVMPs and the early studies that led to their classification represents an important event in our understanding of the structural forms of the SVMPs. The SVMPs were subdivided into the P-I, P-II and P-III protein classes. The noticeable characteristic that distinguished the different classes was their size (molecular weight) differences and domain structure: Class I (P-I), the small SVMPs, have molecular masses of 20-30 kDa, contain only a pro domain and the proteinase domain; Class II (P-II), the medium size SVMPs, molecular masses of 30-60 kDa, contain the pro domain, proteinase domain and disintegrin domain; Class III (P-III), the large SVMPs, have molecular masses of 60-100 kDa, contain pro, proteinase, disintegrin-like and cysteine-rich domain structure. Another significant advance in the SVMP field was the characterization of the crystal structure of the first P-I class SVMP. The structures of other P-I SVMPs soon followed and the structures of P-III SVMPs have also been determined. The active site of the metalloproteinase domain has a consensus HEXXHXXGXXHD sequence and a Met-turn. The "Met-turn" structure contains a conserved Met residue that forms a hydrophobic basement for the three zinc-binding histidines in the consensus sequence. Copyright © 2012 Elsevier Ltd. All rights reserved.
Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...
Ramos, Henrique Roman; Vassão, Ruth Camargo; de Roodt, Adolfo Rafael; Santos E Silva, Ed Carlos; Mirtschin, Peter; Ho, Paulo Lee; Spencer, Patrick Jack
Although rare, coral snake envenomation is a serious health threat in Brazil, because of the highly neurotoxic venom and the scarcely available antivenom. The major bottleneck for antivenom production is the low availability of venom. Furthermore, the available serum is not effective against all coral snake species found in Brazil. An alternative to circumvent the lack of venom for serum production and the restricted protection of the actually available antivenom would be of great value. We compared the Brazilian coral snake and mono and polyvalent Australian antivenoms in terms of reactivity and protection. The immunoreactivity of venoms from 9 coral snakes species were assayed by ELISA and western blot using the Brazilian Micrurus and the Australian pentavalent as well as monovalent anti-Notechis, Oxyuranus and Pseudechis antivenoms. Neutralization assays were performed in mice, using 3 LD 50 of the venoms, incubated for 30 minutes with 100 μL of antivenom/animal. All the venoms reacted against the autologous and heterologous antivenoms. Nevertheless, the neutralization assays showed that the coral snake antivenom was only effective against M. corallinus, M. frontalis, M. fulvius, M. nigrocinctus and M. pyrrhocryptus venoms. On the other hand, the Australian pentavalent antivenom neutralized all venoms except the one from M. spixii. A combination of anti-Oxyuranus and Pseudechis monovalent sera, extended the protection to M. altirostris and, partially, to M. ibiboboca. By adding Notechis antivenom to this mixture, we obtained full protection against M. ibiboboca and partial neutralization against M. lemniscatus venoms. Our findings confirm the limited effectiveness of the Brazilian coral snake antivenom and indicate that antivenoms made from Australian snakes venoms are an effective alternative for coral snake bites in South America and also in the United States were coral snake antivenom production has been discontinued.
Chan, Yau Sang; Cheung, Randy Chi Fai; Xia, Lixin; Wong, Jack Ho; Ng, Tzi Bun; Chan, Wai Yee
Snake venoms are complex mixtures of small molecules and peptides/proteins, and most of them display certain kinds of bioactivities. They include neurotoxic, cytotoxic, cardiotoxic, myotoxic, and many different enzymatic activities. Snake envenomation is a significant health issue as millions of snakebites are reported annually. A large number of people are injured and die due to snake venom poisoning. However, several fatal snake venom toxins have found potential uses as diagnostic tools, therapeutic agent, or drug leads. In this review, different non-enzymatically active snake venom toxins which have potential therapeutic properties such as antitumor, antimicrobial, anticoagulating, and analgesic activities will be discussed.
Egyptian cobra Naja haje haje) and puffadder (Bills arietans). Considerable differences in electrophoretic characteristics were found between fresh venom and commercial venom samples from the same species of snake. These differences could be attributed partly to the instability of snake venom under conditions of drying ...
Hossain, M Z; Atiqullah, S; Saha, A C; Chowdhury, A J; Jahangir, K M; Faiz, M A
A 35-year-old so called snake-expert from Thakurgaon district was admitted in Medicine department of Rangpur Medical College Hospital (RpMCH), Rangpur, Bangladesh on 2nd November 2007 with history of bites by a cobra snake. He was famous for his outstanding works to establish a snake farm first ever in Bangladesh. He had a collection of more than one hundred snakes of different species. He used to hatch eggs of the snakes, feed the young-snakes, collect venoms and sell those. Everyday many visitors used to visit his farm to watch exciting games with poisonous snakes. Several satellite television (TV) channels and some daily newspapers had covered him on different occasions. He was accidentally bitten by a newly caught hungry cobra snake while recording for a satellite TV channel. Following bites he was brought to the hospital three and a half hours later. By that time, neurotoxicity developed. Repeated doses of Anti Snake Venom (ASV) along with respiratory support and other supportive cares were provided. Despite utmost care feasible at RpMCH, patient expired around 49 hours later.
Alirol, Emilie; Sharma, Sanjib Kumar; Bawaskar, Himmatrao Saluba; Kuch, Ulrich; Chappuis, François
.... Despite increasing knowledge of snake venoms' composition and mode of action, good understanding of clinical features of envenoming and sufficient production of antivenom by Indian manufacturers...
Chanhome, L; Cox, M J; Wilde, H; Jintakoon, P; Chaiyabutr, N; Sitprija, V
Thailand has an abundance of venomous snakes. Among the neurotoxic family Elapidae, there are three species of the genus Naja (cobras), three of the genus Bungarus (kraits), and the king cobra of the genus Ophiophagus. Other Elapidae snakes in Thailand include sea snakes and Asian coral snakes of the genus Calliophis. They have potent venoms but rarely bite humans. Tissue and hemotoxic snakes are represented by family Viperidae, subfamilies Viperinae and Crotalinae. They remain an occupational hazard for farmers and rubber tappers, causing serious morbidity but only rare deaths, since competent treatment is now widely available throughout Thailand. Purified equine antivenin is manufactured locally for the monocled and Siamese spitting cobras (Naja kaouthia and N. siamensis), king cobra (Ophiophagus hannah), banded krait (Bungarus fasciatus), most green pit vipers (Trimeresurus sp.), Malayan pit viper (Calloselasma rhodostoma), and the Siamese Russell's viper (Daboia russelli siamensis).
Dehghani R.1 PhD,
Full Text Available Aims Venomous snake bites are public health problems in different parts of the world. The most specific mainstay in the treatment of envenomation is anti-venom. To treat the envenomation, it is very important to identify the offending species. This study was designed to determine the penetrating pattern of fangs and teeth of some viper snakes. Materials & Methods This descriptive study was performed on live venomous and nonvenomous snakes from 2010 till 2011. All 47 sample snakes were collected from different regions of Isfahan province such as Kashan City, Ghamsar, Niasar, Mashhad Ardehal, Taher- Abad and Khozagh. Their mouths were inspected every two weeks and development of their fangs and teeth were recorded by taking clear digital photos. Fangs and teeth patterns of samples were drawn and the results were compared. Findings One or two wounds appeared as typical fang marks at the bite site of venomous snakes while non-venomous snakes had two carved rows of small teeth. Three different teeth and fang patterns were recognized in venomous snakes which were completely different. Conclusion The fang marks of venomous snakes do not always have a common and classic pattern and there are at least 3 different patterns in Isfahan province, Iran.
Dehghani, Rouhullah; Rabani, Davarkhah; Panjeh Shahi, Morteza; Jazayeri, Mehrdad; Sabahi Bidgoli, Mohammd
Snake bites are one of the significant health problems in the tropical and subtropical regions. Snake bite is a common medical emergency in Iran, and the epidemiological features and management of such cases vary from region to region. This present research study was conducted to obtain new information about the epidemiology of snake bites in the region of Kashan, located in the central part of Iran. This research was a descriptive retrospective study. Data from 2004 to 2011 of snakebite cases were collected from case reports. Information included; age and sex of the victim, district, month of incident, mortality, and time of bite. The results of this study showed that the majority of snake bite patients were male (96%). The age distribution of patients indicated that the greatest rate of snake bites occurred among the 15-24 year old group. Data collected in this study revealed that the highest incidence of snake bite cases took place in summer (60%) and the lowest number occurred in winter, with no snake bite cases being recorded. The peak number of snakebite cases was seen during June-September. It was concluded that snake bite cases in Kashan are similar to other areas in Iran from an epidemiological point of view, including; age distribution rates, gender and site of the bites. The existence of Macrov ipera lebetina, a dangerous venomous snake, can cause a range of clinical effects among residents in central parts of Iran, such as Kashan area.
Tanaka, Gabriela D; Pidde-Queiroz, Giselle; de Fátima D Furtado, Maria; van den Berg, Carmen; Tambourgi, Denise V
The genus Micrurus, coral snakes (Serpentes, Elapidae), comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s) present in the venoms, which disrupts complement activation control. Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.
Tanaka Gabriela D
Full Text Available Abstract Background The genus Micrurus, coral snakes (Serpentes, Elapidae, comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. Results In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s present in the venoms, which disrupts complement activation control. Conclusion Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.
Non-venomous snake bite and snake bite without envenoming in a brazilian teaching hospital: analysis of 91 cases Acidentes por serpentes não-peçonhentas e acidentes por serpentes peçonhentas sem envenenamento em hospital universitário brasileiro: análise de 91 casos
Paulo Vitor Portella Silveira
Full Text Available A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii. In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming. The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%, in the 10-19 years age group (26;29%, in the lower limbs (51/74;69%, between 6 A. M. and 2 P.M. (49;61% and in the month of April (16; 18%. One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.Um levantamento retrospectivo de 473 casos de acidentes ofídicos admitidos em um hospital-escola brasileiro de 1984 a 1990 revelou 91 casos sem envenenamento e/ou causados por serpentes não-peçonhentas. Em 17 casos a serpente foi identificada e um paciente foi mordido por um réptil que se assemelha às serpentes (Amphisbaena mertensii. Em 43 casos o diagnóstico foi clínico (sinal das presas na ausência de sinais de envenenamento. Os demais 30 casos foram de pacientes que se queixavam de terem sido mordidos mas que não apresentavam nem sinal de
K. J. Ananda
Full Text Available Two dog viz. Labrador and Alsatian cross were presented to the peripheral hospital with a history of frothy salivation, dull, depressed, abnormal gait and with recumbent position. They were diagnosed for snake bite based on the history and physical examination. The hematological parameters showed reduced values of hemoglobin, packed cell volume and increased total leukocyte count. The biochemical values showed elevated levels of alanine aminotransferase and creatinine. The successful treatment was done with anti-snake venom, fluid, corticosteroid, muscuranic receptor antagonist and antibiotic with careful monitoring. [Vet. World 2009; 2(2.000: 66-67
Full Text Available Cytotoxicity of venoms from eleven medically important snakes found in Southeast Asia (Naja kaouthia, Naja siamensis, Naja sumatrana, Ophiophagus hannah, Bungarus candidus, Bungarus fasciatus, Enhydrina schistosa, Calloselasma rhodostoma, Trimeresurus purpureomaculatus and Tropidolaemus sumatranus was determined, based on the MTS cytotoxicity assay, which determines the survival of viable cells in monolayer MDCK and Vero cell cultures upon exposure to the snake venoms. Snake venom toxicity was expressed as the venom dose that killed 50% of the cells (CTC50 under the assay conditions. Venoms of C. rhodostoma (2.6 µg/mL, 1.4 µg/mL and O. hannah were the most cytotoxic (3.8 µg/mL, 1.7 µg/mL whereas N. siamensis venom showed the least cytotoxicity (51.9 µg/mL, 45.7 µg/mL against Vero and MDCK cells, respectively. All the viper venoms showed higher cytotoxic potency towards both Vero and MDCK cell lines, in comparison to krait and cobra venoms. E. schistosa did not cause cytotoxicity towards MDCK or Vero cells at the tested concentrations. The cytotoxicity correlates well with the known differences in the composition of venoms from cobras, kraits, vipers and sea snakes.
Urdaneta, Aldo H; Bolaños, Federico; Gutiérrez, José María
The feeding behavior and venom toxicity of the coral snake Micrurus nigrocinctus (Serpentes: Elapidae) on its natural prey in captivity were investigated. Coral snakes searched for their prey (the colubrid snake Geophis godmani) in the cages. Once their preys were located, coral snakes stroke them with a rapid forward movement, biting predominantly in the anterior region of the body. In order to assess the role of venom in prey restraint and ingestion, a group of coral snakes was 'milked' in order to drastically reduce the venom content in their glands. Significant differences were observed between snakes with venom, i.e., 'nonmilked' snakes, and 'milked' snakes regarding their behavior after the bite. The former remained hold to the prey until paralysis was achieved, whereas the latter, in the absence of paralysis, moved their head towards the head of the prey and bit the skull to achieve prey immobilization by mechanical means. There were no significant differences in the time of ingestion between these two groups of coral snakes. Susceptibility to the lethal effect of coral snake venom greatly differed in four colubrid species; G. godmani showed the highest susceptibility, followed by Geophis brachycephalus, whereas Ninia psephota and Ninia maculata were highly resistant to this venom. In addition, the blood serum of N. maculata, but not that of G. brachycephalus, prolonged the time of death of mice injected with 2 LD(50)s of M. nigrocinctus venom, when venom and blood serum were incubated before testing. Subcutaneous injection of coral snake venom in G. godmani induced neurotoxicity and myotoxicity, without causing hemorrhage and without affecting heart and lungs. It is concluded that (a) M. nigrocinctus venom plays a role in prey immobilization, (b) venom induces neurotoxic and myotoxic effects in colubrid snakes which comprise part of their natural prey, and (c) some colubrid snakes of the genus Ninia present a conspicuous resistance to the toxic action of M
Nazim, Muhammad H; Gupta, Sanjay; Hashmi, Syed; Zuberi, Jamshed; Wilson, Alison; Roberts, Lawrence; Karimi, Kamran
Venomous snakebites are a rare but dangerous and potentially deadly condition in the U.S.. Most bites in the U. S. result from envenomation with snakes of the family Viperidae, subfamily Crotalinae, which includes rattlesnakes and copperheads. Treatment includes a comprehensive work-up to look for possible hematologic, neurologic, renal, and cardiovascular abnormalities, local wound care, systemic antivenom administration, tetanus prophylaxis, antibiotics in the presence of infection and surgical treatment if needed, which may include debridement, fasciotomy and rarely amputation. All these patients should be observed for a minimum of 8 hours. Any evidence of envenomation mandates a minimum of 24 hours of in-hospital observation. A grading system to classify the severity of envenomation is described. The most commonly used antivenom in the U.S. is CroFab, which has a much lower incidence of acute or delayed allergic reactions compared to the older antivenoms. When allergic reactions do occur, they are usually of mild to moderate severity. With the improved risk-benefit ratio of CroFab, antivenom is indicated with any grade of envenomation. In this a retrospective study, we will review our experience with 25 snakebite victims admitted to the West Virginia University over a five years period.
Gowtham, Yashonandana J; Kumar, M S; Girish, K S; Kemparaju, K
Unlike Naja naja, Bungarus caeruleus, Echis carinatus, and Daboia/Vipera russellii venoms, Ophiophagus hannah venom is medically ignored in the Indian subcontinent. Being the biggest poisonous snake, O. hannah has been presumed to inject several lethal doses of venom in a single bite. Lack of therapeutic antivenom to O. hannah bite in India makes any attempt to save the victim a difficult exercise. This study was initiated to compare O. hannah venom with the above said venoms for possible interference in hemostasis. Ophiophagus hannah venom was found to actively interfere in hemostatic stages such as fibrin clot formation, platelet activation/aggregation, and fibrin clot dissolution. It decreased partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin clotting time (TCT). These activities are similar to that shown by E. carinatus and D. russellii venoms, and thus O. hannah venom was found to exert procoagulant activity through the common pathway of blood coagulation, while N. naja venom increased aPTT and TCT but not PT, and hence it was found to exert anticoagulant activity through the intrinsic pathway. Venoms of O. hannah, E. carinatus, and D. russellii lack plasminogen activation property as they do not hydrolyze azocasein, while they all show plasmin-like activity by degrading the fibrin clot. Although N. naja venom did not degrade azocasein, unlike other venoms, it showed feeble plasmin-like activity on fibrin clot. Venom of E. carinatus induced clotting of human platelet rich plasma (PRP), while the other three venoms interfered in agonist-induced platelet aggregation in PRP. Venom of O. hannah least inhibited the ADP induced platelet aggregation as compared to D. russellii and N. naja venoms. All these three venoms showed complete inhibition of epinephrine-induced aggregation at varied doses. However, O. hannah venom was unique in inhibiting thrombin induced aggregation.
Khin Than Yee
Full Text Available Russell’s viper bites are potentially fatal from severe bleeding, renal failure and capillary leakage. Snake venom metalloproteinases (SVMPs are attributed to these effects. In addition to specific antivenom therapy, endogenous inhibitors from snakes are of interest in studies of new treatment modalities for neutralization of the effect of toxins. Two major snake venom metalloproteinases (SVMPs: RVV-X and Daborhagin were purified from Myanmar Russell’s viper venom using a new purification strategy. Using the Next Generation Sequencing (NGS approach to explore the Myanmar RV venom gland transcriptome, mRNAs of novel tripeptide SVMP inhibitors (SVMPIs were discovered. Two novel endogenous tripeptides, pERW and pEKW were identified and isolated from the crude venom. Both purified SVMPs showed caseinolytic activity. Additionally, RVV-X displayed specific proteolytic activity towards gelatin and Daborhagin showed potent fibrinogenolytic activity. These activities were inhibited by metal chelators. Notably, the synthetic peptide inhibitors, pERW and pEKW, completely inhibit the gelatinolytic and fibrinogenolytic activities of respective SVMPs at 5 mM concentration. These complete inhibitory effects suggest that these tripeptides deserve further study for development of a therapeutic candidate for Russell’s viper envenomation.
By end of the thirteenth century, surgeons and university-trained physicians in Western Europe had a plethora of authorities from the Greco-Roman and Arabic tradition from which to consult for the treatment of snake-bites. Venomous animals receive the largest share of attention in the literature on biting animals. Nearly all of the sources focus on the idea of the animal biting or puncturing the skin’s surface with their mouths and few poisonous animals where the venom is passed on through the skin or hairs are mentioned. Venomous animals frequently appear in discussions on poisons in general, with poisons of animal, mineral or vegetable origin. The bulk of the discourse dealt with venomous snakes and rabid dogs, the latter considered venomous due to its ‘poisonous’ saliva, and to a lesser extent, scorpions and spiders. In general the bites of non-venomous animals received scant attention. Unlike modern taxonomical categories, medieval categories for animals were usually connected to the movement or the locale of the animal: flying animals, animals in water, land animals (which mainly covered quadrupeds), and crawling animals. It is in the latter category that snakes were located, along with lizards. PMID:25729094
By end of the thirteenth century, surgeons and university-trained physicians in Western Europe had a plethora of authorities from the Greco-Roman and Arabic tradition from which to consult for the treatment of snake-bites. Venomous animals receive the largest share of attention in the literature on biting animals. Nearly all of the sources focus on the idea of the animal biting or puncturing the skin’s surface with their mouths and few poisonous animals where the venom is passed on through th...
Oswald Vital Brazil
Full Text Available Coral snakes, the New World Elapidae, are included in the genera Micniroides and Micrurus. The genus Mlcrurus comprises nearly all coral snake species and those which are responsible for human snake-bite accidents. The following generalizations concerning the effects induced by their venoms, and their venom-properties can be made. Coral snake venoms are neurotoxic, producing loss of muscle strenght and death by respiratory paralysis. Local edema and necrosis are not induced nor blood coagulation or hemorrhages. Proteolysis activity is absent or of very low grade. They display phospholipase A2 activity. Nephrotoxic effects are not evoked. The main toxins from elapid venoms are postsynaptic and presynaptic neurotoxins and cardiotoxins. Phospholipases A2 endowed with myonecrotic or cardiotoxin-like properties are important toxic components from some elapid venoms. The mode of action of Micrurus frontalis, M. lemniscatus, M. corallinus and M. fulvius venoms has been investigated in isolated muscle preparations and is here discussed. It is shown that while M. frontalis and M. lemniscatus venoms must contain only neurotoxins that act at the cholinergic end-plate receptor (postsynaptic neurotoxins, M. corallinus venom also inhibits evoked acetylcholine release by the motor nerve endings (presynaptic neurotoxin-like effect and M. fulvius induces muscle fiber membrane depolarization (cardiotoxin-like effect. The effects produced by M. corallinus and M. fulvius venoms in vivo in dogs and M. frontalis venom in dogs and monkeys are also reported.
Wolpert, H. D.
Some think that using derivatives of snake venom for medical purposes is the modern version of snake oil but they are seriously misjudging the research potentials of some of these toxins in medicines of the 2000's. Medical trials, using some of the compounds has proven their usefulness. Several venoms have shown the possibilities that could lead to anticoagulants, helpful in heart disease. The blood clotting protein from the taipan snake has been shown to rapidly stop excessive bleeding. The venom from the copperhead may hold an answer to breast cancer. The Malaysian pit viper shows promise in breaking blood clots. Cobra venom may hold keys to finding cures for Parkinson's disease and Alzheimer's. Rattlesnake proteins from certain species have produced blood pressure medicines. Besides snake venoms, venom from the South American dart frog, mollusks (i.e. Cone Shell Snail), lizards (i.e. Gila Monster & Komodo Dragon), some species of spiders and tarantulas, Cephalopods, mammals (i.e. Platypus & Shrews), fish (i.e. sting rays, stone fish, puffer fish, blue bottle fish & box jelly fish), intertidal marine animals (echinoderms)(i.e. Crown of Thorn Star Fish & Flower Urchin) and the Honeybee are being investigated for potential medical benefits.
Jarwani, Bhavesh; Jadav, Pradeep; Madaiya, Malhar
Snake bite is a common medical emergency faced mainly by the rural populations in tropical and subtropical countries with heavy rainfall and humid climate. Although India is a single largest contributor of snake bite cases, reporting is very poor. There is hardly any publication of the same from Gujarat state that is developing at a good pace. Hence, we aimed to study the snake bite cases with particular attention to demography, epidemiology, and clinical profile. The present descriptive, observational study was carried out at the Emergency Medicine Department of a tertiary care center in Ahmedabad, Gujarat. This department is one if the firsts to get recognized by the Medical Council of India. This is a cross-sectional single-center study. Cases were entered into the prescribed form, and detailed information regarding demographic, epidemiologic, and clinical parameters was entered. Data were analyzed using Epi2000. Means and frequencies for each variable were calculated. Majority (67.4%) of the snake bite victims were in the age group between 15 and 45 years. Majority were male victims (74.2%). 71% victims of snake bite lived in rural areas. Farmers and laborers were the main victims. 61.2% incidents took place at night time or early morning (before 6 a.m.). 64% patients had bite mark on the lower limb. 40% victims had seen the snake. Eight patients had snake bite, but were asymptomatic. 52% had neuroparalytic manifestation, 34% were asymptomatic, and 9.6% had hemorrhagic manifestation. 14% cases received treatment within 1 h of the bite and 64.84% within 1-6 h after the bite. First aid given was in the form of application of tourniquet (16.2%), local application of lime, chillies, herbal medicine, etc., (1%). 2.20% cases were sensitive to anti-snake venom. Only three patients died. In this region (Gujarat), neuroparalytic manifestation of snake bite is more prevalent. Cobra and krait are the commonest types of poisonous snakes. The time of seeking treatment has
Warrell, David A
Research is discussed in the areas of venomous snake taxonomy, epidemiology, species diagnosis, defining the clinical phenotype of human envenoming, pathophysiological mechanisms of envenoming, clinical testing of antivenoms and prevention of snake-bite through community education. This work was carried out over the past 40 years in many countries in four tropical continents. The help and friendship of a large number of collaborators is gratefully acknowledged. Copyright © 2012 Elsevier Ltd. All rights reserved.
Georgieva, Dessislava; Ohler, Michaela; Seifert, Jana; von Bergen, Martin; Arni, Raghuvir K; Genov, Nicolay; Betzel, Christian
The snake venomic of Crotalus durissus terrificus was analyzed by 2-D and 1-D electrophoresis and subsequent MS/MS and enzymatic assays. The venomic of the South American rattlesnake comprises toxins from seven protein families: phospholipases A(2), serine proteinases, ecto-5'-nucleotidases, metalloproteinases, nerve growth factors, phosphodiesterases, and glutaminyl cyclase. The venom toxin composition correlates with the clinical manifestation of the crotalinae snake bites and explains pathological effects of the venom such as neurotoxicity, systemic myonecrosis, hemostatic disorders, myoglobinuria, and acute renal failure. The vast majority of toxins are potentially involved in neurotoxicity, myotoxicity, and coagulopathy. The predominant venom components are neurotoxic phospholipases A(2) and serine proteinases. The venom is a rich source of 5'-nucleotidases (7.8% of the identified toxins) inducing hemostatic disorders. Analysis of the venom protein composition provided a catalogue for secreted toxins. The venomic composition of Crotalus d. terrificus and venom gland transcriptome of the synonymous subspecies Crotalus d. collilineatus show differences in the occurrence of protein families and in the abundance of toxins. Some of the venom components identified by the proteomic analysis were not reported in the transcriptome of the Crotalus d. collilineatus venom gland. Enzymatic activities of the Crotalus d. terrificus venom were determined and correlated with the proteomic composition.
Hiremath, Vilas; Nanjaraj Urs, A N; Joshi, Vikram; Suvilesh, K N; Savitha, M N; Urs Amog, Prathap; Rudresha, G V; Yariswamy, M; Vishwanath, B S
Snakebite is a global health problem affecting millions of people. According to WHO, India has the highest mortality and/or morbidity due to snakebite. In spite of commendable research on Indian BIG FOUR venomous species; Naja naja and Bungarus caeruleus (elapid); Daboia russelii and Echis carinatus (viperid), no significant progress has been achieved in terms of diagnosis and management of biting species with appropriate anti-snake venom. Major hurdle is identification of offending species. Present study aims at differentiation of Indian BIG FOUR snake venoms based on their distinguish action on rodent blood coagulation. Assessment of coagulation alterations by elapid venoms showed negligible effect on re-calcification time, prothrombin time, activated partial thromboplastin time and factors assay (I, II, V, VIII and X) both in vitro and in vivo. However, viperid venoms demonstrated significant anticoagulant status due to their remarkable fibrinogen degradation potentials as supported by fibrinogenolytic activity, fibrinogen zymography and rotational thromboelastometry. Though results provide hint on probable alterations of Indian BIG FOUR snake venoms on blood coagulation, the study however needs validation from human victim's samples to ascertain its reliability for identification of biting snake species. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available INTRODUCTION Snake bite is a common and frequently devastating environmental and occupational problem, especially in rural areas of tropical developing countries. Snake bite incidence is high in Andhra Pradesh. With the onset of monsoon the incidence of snake bite used to increase. METHODS Present study is a retrospective study in which all the data of snake bite cases admitted in the Konaseema Institute of Medical Sciences was collected in last two years; details of the patient was obtained from bed head ticket. RESULTS In two years of data collection, 46 snake bite cases are found as per our record. Out of 46 patients, twenty seven were male and nineteen were female. Maximum twenty two (22 patients were between ages 20 to 40 years. Out of forty six patients, forty four recovered and only two patients died, cause of death was acute pulmonary oedema with cardiac arrhythmia. DISCUSSION Most of the patients were given ASV (anti-snake venom, out of that only four patients developed reaction to ASV. Most of the patients who have received ASV were recovered. Only two deaths were reported which was due to acute pulmonary oedema with cardiac arrhythmia. CONCLUSION Awareness and education about snake is required.
Chauhan, Vivek; Thakur, Suman
Snake bite envenomations are common in rural areas and the incidence peaks during monsoons in India. Prominent venomous species have been traditionally labeled as the 'big four' that includes Cobra, Krait, Russel's viper and Saw scaled viper. Systematic attempts for identification and classification of prevalent snakes in various states of India are missing till now and there is no concrete data on this aspect. The published literature however shows that some species of snakes are more prevalent in a particular region than the other parts of India e.g. Saw scaled vipers in Rajasthan. We reviewed the published literature from various parts of India and found that there is a North-South divide in the snake bite profile from India. Neurotoxic envenomations are significantly higher in North India compared to South India where Hematotoxic envenomations are prevalent. Russel's viper causes local necrosis, gangrene and compartment syndrome. These manifestations have never been reported in North Indian snake bite profile in the published literature. Early morning neuroparalysis caused by Krait is a common problem in North India leading to high mortality after snake bite. This review presents supporting evidence for the North-South divide and proposes a way forward in formulation and revision of guidelines for snake bite in India.
Full Text Available Snake bite envenomations are common in rural areas and the incidence peaks during monsoons in India. Prominent venomous species have been traditionally labeled as the ′big four′ that includes Cobra, Krait, Russel′s viper and Saw scaled viper. Systematic attempts for identification and classification of prevalent snakes in various states of India are missing till now and there is no concrete data on this aspect. The published literature however shows that some species of snakes are more prevalent in a particular region than the other parts of India e.g. Saw scaled vipers in Rajasthan. We reviewed the published literature from various parts of India and found that there is a North-South divide in the snake bite profile from India. Neurotoxic envenomations are significantly higher in North India compared to South India where Hematotoxic envenomations are prevalent. Russel′s viper causes local necrosis, gangrene and compartment syndrome. These manifestations have never been reported in North Indian snake bite profile in the published literature. Early morning neuroparalysis caused by Krait is a common problem in North India leading to high mortality after snake bite. This review presents supporting evidence for the North-South divide and proposes a way forward in formulation and revision of guidelines for snake bite in India.
Rogers, Lynn L; Mansfield, Susan A; Hornby, Kathleen; Hornby, Stewart; Debruyn, Terry D; Mize, Malvin; Clark, Rulon; Burghardt, Gordon M
Bears are often considered ecological equivalents of large primates, but the latter often respond with fear, avoidance, and alarm calls to snakes, both venomous and non-venomous, there is sparse information on how bears respond to snakes. We videotaped or directly observed natural encounters between black bears (Ursus americanus) and snakes. Inside the range of venomous snakes in Arkansas and West Virginia, adolescent and adult black bears reacted fearfully in seven of seven encounters upon b...
Thakur, Rupamoni; Mukherjee, Ashis K
Protease inhibitors are important constituents of snake venom and play important roles in the pathophysiology of snakebite. Recently, research on snake venom protease inhibitors has provided valuable information to decipher the molecular details of various biological processes and offer insight for the development of some therapeutically important molecules from snake venom. The process of blood coagulation and fibrinolysis, in addition to affecting platelet function, are well known as the major targets of several snake venom protease inhibitors. This review summarizes the structure-functional aspects of snake venom protease inhibitors that have been described to date. Because diverse biological functions have been demonstrated by protease inhibitors, a comparative overview of their pharmacological and pathophysiological properties is also highlighted. In addition, since most snake venom protease inhibitors are non-toxic on their own, this review evaluates the different roles of individual protease inhibitors that could lead to the identification of drug candidates and diagnostic molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.
Major lower limb amputations following snake bite gangrene have been reported from the savannah belt of Nigeria. In bites delivered to the upper limb, amputations are often of the digits (minor amputations). We report the case of a male farmer who had an above elbow amputation after a snake bite to the hand. Explanation ...
Full Text Available The existence of mammals and reptilia with a natural resistance to snake venoms is known since a long time. This fact has been subjected to the study by several research workers. Our experiments showed us that in the marsupial Didelphis marsupialis, a mammal highly resistant to the venom of Bothrops jararaca, and other Bothrops venoms, has a genetically origin protein, a alpha-1, acid glycoprotein, now highly purified, with protective action in mice against the jararaca snake venom.
Rogers, Lynn L; Mansfield, Susan A; Hornby, Kathleen; Hornby, Stewart; Debruyn, Terry D; Mize, Malvin; Clark, Rulon; Burghardt, Gordon M
Bears are often considered ecological equivalents of large primates, but the latter often respond with fear, avoidance, and alarm calls to snakes, both venomous and non-venomous, there is sparse information on how bears respond to snakes. We videotaped or directly observed natural encounters between black bears (Ursus americanus) and snakes. Inside the range of venomous snakes in Arkansas and West Virginia, adolescent and adult black bears reacted fearfully in seven of seven encounters upon becoming aware of venomous and non-venomous snakes; but in northern Michigan and Minnesota where venomous snakes have been absent for millennia, black bears showed little or no fear in four encounters with non-venomous snakes of three species. The possible roles of experience and evolution in bear reactions to snakes and vice versa are discussed. In all areas studied, black bears had difficulty to recognize non-moving snakes by smell or sight. Bears did not react until snakes moved in 11 of 12 encounters with non-moving timber rattlesnakes (Crotalus horridus) and four species of harmless snakes. However, in additional tests in this study, bears were repulsed by garter snakes that had excreted pungent anal exudates, which may help explain the absence of snakes, both venomous and harmless, in bear diets reported to date. PMID:25635152
Corrêa-Netto, Carlos; Junqueira-de-Azevedo, Inácio de L M; Silva, Débora A; Ho, Paulo L; Leitão-de-Araújo, Moema; Alves, Maria Lúcia M; Sanz, Libia; Foguel, Débora; Zingali, Russolina Benedeta; Calvete, Juan J
The venom proteomes of Micrurus altirostris and M. corallinus were analyzed by combining snake venomics and venom gland transcriptomic surveys. In both coral snake species, 3FTx and PLA(2) were the most abundant and diversified toxin families. 33 different 3FTxs and 13 PLA(2) proteins, accounting respectively for 79.5% and 13.7% of the total proteins, were identified in the venom of M. altirostris. The venom of M. corallinus comprised 10 3FTx (81.7% of the venom proteome) and 4 (11.9%) PLA(2) molecules. Transcriptomic data provided the full-length amino acid sequences of 18 (M. altirostris) and 10 (M. corallinus) 3FTxs, and 3 (M. altirostris) and 1 (M. corallinus) novel PLA(2) sequences. In addition, venom from each species contained single members of minor toxin families: 3 common (PIII-SVMP, C-type lectin-like, L-amino acid oxidase) and 4 species-specific (CRISP, Kunitz-type inhibitor, lysosomal acid lipase in M. altirostris; serine proteinase in M. corallinus) toxin classes. The finding of a lipase (LIPA) in the venom proteome and in the venom gland transcriptome of M. altirostris supports the view of a recruitment event predating the divergence of Elapidae and Viperidae more than 60 Mya. The toxin profile of both M. altirostris and M. corallinus venoms points to 3FTxs and PLA(2) molecules as the major players of the envenoming process. In M. altirostris venom, all major, and most minor, 3FTxs display highest similarity to type I α-neurotoxins, suggesting that these postsynaptically acting toxins may play the predominant role in the neurotoxic effect leading to peripheral paralysis, respiratory arrest, and death. M. corallinus venom posesses both, type I α-neurotoxins and a high-abundance (26% of the venom proteome) protein of subfamily XIX of 3FTxs, exhibiting similarity to bucandin from Malayan krait, Bungarus candidus, venom, which enhances acetylcholine release presynaptically. This finding may explain the presynaptic neurotoxicity of M. corallinus venom
Rachel B Currier
Full Text Available Venom is a critical evolutionary innovation enabling venomous snakes to become successful limbless predators; it is therefore vital that venomous snakes possess a highly efficient venom production and delivery system to maintain their predatory arsenal. Here, we exploit the unusual stability of messenger RNA in venom to conduct, for the first time, quantitative PCR to characterise the dynamics of gene expression of newly synthesised venom proteins following venom depletion. Quantitative PCR directly from venom enables real-time dynamic studies of gene expression in the same animals because it circumvents the conventional requirement to sacrifice snakes to extract mRNA from dissected venom glands. Using qPCR and proteomic analysis, we show that gene expression and protein re-synthesis triggered by venom expulsion peaks between days 3-7 of the cycle of venom replenishment, with different protein families expressed in parallel. We demonstrate that venom re-synthesis occurs very rapidly following depletion of venom stores, presumably to ensure venomous snakes retain their ability to efficiently predate and remain defended from predators. The stability of mRNA in venom is biologically fascinating, and could significantly empower venom research by expanding opportunities to produce transcriptomes from historical venom stocks and rare or endangered venomous species, for new therapeutic, diagnostic and evolutionary studies.
Background Although the cytolytic, neurotoxic and haemolytic actions of snake venoms are well known, the ability of snake venom to induce asthma (as a distinct entity from just difficulty in breathing) is not previously reported in the literature. Methods The case records of the patient in the index case and a review of existing ...
Wozniak, Edward J; Wisser, John; Schwartz, Michael
Each hurricane season, emergency-preparedness deployment teams including but not limited to the Office of Force Readiness and Deployment of the US Public Health Service, Federal Emergency Management Agency, Deployment Medical Assistance Teams, Veterinary Medical Assistance Teams, and the US Army and Air Force National Guard are at risk for deploying into hurricane-stricken areas that harbor indigenous hazards, including those posed by venomous snakes. North America is home to 2 distinct families of venomous snakes: 1) Viperidae, which includes the rattlesnakes, copperheads, and cottonmouths; and 2) Elapidae, in which the only native species are the coral snakes. Although some of these snakes are easily identified, some are not, and many rank among the most feared and misunderstood animals. This article specifically addresses all the native species of venomous snakes that inhabit the hurricane-prone regions of North America and is intended to serve as a reference to snake identification, basic field safety procedures, and the currently recommended first-aid measures for snakebite casualties.
Seneviratne U; Dissanayake S
BACKGROUND AND AIMS: Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL: Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of...
Usman M Sani
Full Text Available Background: Snake bite with envenomation is a medical emergency. Children are at risk of severe manifestations due to small body mass. Unlike adult population, there is limited data on snake bite among children in Sokoto, North-Western Nigeria. We described the presentation and outcome of snake bite in children presenting to the Emergency Pediatric Unit of Usmanu Danfodiyo University Teaching Hospital, Sokoto. Materials and Methods: Case records of all children managed for snake bites from 1 st January 2003 to 31 st December 2012 were retrospectively reviewed. Demographic and other relevant information were retrieved and data analyzed using Microsoft Excel. Results: Out of 23,570 Pediatric admissions, 36 children had snake bites giving prevalence of 0.0015 (1.5/1000. Male: Female ratio was 1.6:1, with a mean (standard deviation age of 9.6 ± 2.8 years (range = 1-14 years. Snakebites involved the lower limbs in 52.8%; and at home in 69.4%, and during the night in 58.3% of patients. The highest prevalence of bite was between April and July. Features of envenomation included local swelling (100%, prolonged clotting time (61.1% and spontaneous hemorrhage (epistaxis and hematemesis in 11.1%. One patient (2.8% had seizure which may be incidental, though common causes such as hypoglycemia, malaria and meningitis were excluded by laboratory investigations. Polyvalent anti-snake venom was administered in 29 (80.6% children, with adverse reaction observed in 13.8% (4/29 of the patients. Thirteen patients (36.1% signed against medical advice while the remaining 23 (63.9% were discharged home. Conclusion: Snake envenomation is associated with low morbidity and mortality in our study. Measures aimed at eliminating snake habitats around residential areas should be encouraged.
Bucaretchi, Fábio; Hyslop, Stephen; Vieira, Ronan José; Toledo, Adriana Safioli; Madureira, Paulo Roberto; de Capitani, Eduardo Mello
Coral snakes (Micrurus spp.) are the main representatives of the Elapidae in South America. However, bites by these snakes are uncommon. We retrospectively reviewed the data from 11 individuals bitten by coral snakes over a 20-year period; four were confirmed (snake brought for identification) and seven were highly suspected (neuromuscular manifestations) cases of elapid envenoming. The cases were classified as dry-bite (n = 1, caused by M. lemniscatus; did not receive antivenom), mild (n = 2, local manifestations with no acute myasthenic syndrome; M. frontalis and Micrurus spp.), moderate (n = 5, mild myasthenia) or severe (n = 3, important myasthenia; one of them caused by M. frontalis). The main clinical features upon admission were paresthesia (local, n = 9; generalized, n = 2), local pain (n = 8), palpebral ptosis (n = 8), weakness (n = 4) and inability to stand up (n = 3). No patient developed respiratory failure. Antivenom was used in ten cases, with mild early reactions occurring in three. An anticholinesterase drug was administered in the three severe cases, with a good response in two. No deaths were observed. Despite the high toxicity of coral snake venoms, the prognosis following envenoming is good. In serious bites by M. frontalis or M. lemniscatus, the venom of which acts postsynaptically, anticholinesterases may be useful as an ancillary measure if antivenom is unavailable, if there is a delay in obtaining a sufficient amount, or in those patients given the highest recommended doses of antivenom without improvement of the paralysis or with delayed recovery.
This correspondence argues that the dangerousness of a venomous snake species is not solely determined by the venom characteristics or the lethality of the snake, and recognizes that medical importance comprises a key variable as well. The medical importance of a snake is determined by several factors ? including frequency of medical attention after a bite, local or systemic envenomation provoked by the bite, fatal bites, long term consequences, availability of antivenom therapy as well as th...
The dangerous venomous terrestrial snakes of Iran belong to three groups: the Elapidae (cobras); the Viperinae (true vipers); the Crotalinae (pit vipers). Geographical distribution of each species was determined. Studies on the venoms extracted from the following Iranian snakes, Oxus cobra, Naja naja oxiana, Levantine viper (Afyi), Vipera lebetina, Carpet viper, Echis carinatus, Persian horned viper, Pseudocerastes persicus, Latifii viper, Vipera latifii, Mountain viper, Vipera xanthina and Caucasus pit viper (Agkistrodon halys), indicated that the yield of venom varies in each species. Venoms were compared for their lethality (i.v. LD50 in mice) and their rate of production. The antigenic components of the venoms were compared with their antisera by gel diffusion tests. To obtain the best results from antivenom treatment, the serum should be made against the venom of the local population of snakes or, at least, the commercial antivenom should be controlled for potency by testing with local reference venom.
Aims: Snake bite is an important cause of morbidity and mortality in Nigeria as in many parts of the tropics. This study was undertaken to determine the prevalence and the clinical pattern of snake bite in Gombe. Methods: Two hundred and seven (207) cases of snakebite admitted at the State Specialist Hospital Gombe over ...
Full Text Available Introduction: bite affects about 2 million people every year, with more than 100000 mortalities annually. A person bitten by a snake represents a variety of symptoms. Snake bite might be asymptomatic or with mild local symptoms or even could lead to tissue damage and rapid death. This study aimed to investigate characteristics of snake bite in Northwest Iran. Methods: In this retrospective study, medical records of all patients with final diagnosis of snake bite who were admitted to Sina Clinical-Educational Center, the referral center for envenomation in Northwest Iran were investigated from 2002 to 2012. Demographic information and laboratory findings were collected using a checklist. Results: During a 10 year period, 160 individuals with snake bite were admitted, of which 128 (77.6% were male. With regard to occupation, farmers accounted for the largest portion (n = 57, 34.6%. The most prevalent sites bitten by snakes were right hand (25.5% and left leg (24.8%. Fifty-seven patients (34.5% had leukocytosis and four (2.4% had coagulopathy. Pain and swelling were two main complaints, with vomiting, dizziness, and tingling in extremities coming afterwards. Conclusion: Because snake bite is one of the most important emergencies presenting to emergency department and Iran’s geographic status bears wide spectrum of poisonous snakes, this study was performed to further explore the clinical and epidemiologic details of snake bite.
Morgan, David L; Borys, Douglas J; Stanford, Rhandi; Kjar, Dean; Tobleman, William
The clinical features of bites from Texas coral snakes (Micrurus tener) have not been well studied. Our goal was to review the largest number of victims of Texas coral snakebites to determine their characteristics, effects, treatment, and outcome. Retrospective case series of Micrurus tener exposures reported to the Texas Poison Center Network from 2000 to 2004. Eighty-two patients were included in the analysis. Most (57.3%) were 18 to 49-year-old men. Almost 90% had local swelling, pain, erythema, or paresthesias. Only 7.3% had systemic effects, and none of these were severe. Over half received coral snake antivenin, and 15.9% were given opioids for pain. No patient died and no patient required mechanical ventilation due to hypoventilation from the snakebite. There were more local findings and less severe systemic effects than previously reported. Antivenin is not needed for most of these patients, and opioids may be administered safely.
Oukkache, Naoual; El Jaoudi, Rachid; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc
Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD₅₀) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD₅₀ values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD₅₀ values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD₅₀ values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the
Full Text Available Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD50 of scorpion and snake venoms appears to be an important step to assess (and compare venom toxic activity. Such LD50 values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD50 values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP versus intravenous (IV. The analysis of experimental LD50 values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am is intrinsically more toxic than Androctonus australis hector (Aah species, whereas the latter is more toxic than Buthus occitanus (Bo. Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc is more toxic than either Bitis arietans (Ba or Macrovipera lebetina (Ml species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of
Oukkache, Naoual; Jaoudi, Rachid El; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc
Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD50) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD50 values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD50 values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD50 values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of toxins
Kumar, Praveen K; Ahuja, Shashi; Kumar, Praveen S
The authors wish to report a case of bilateral acute anterior uveitis and optic disc edema following a hemotoxic snake bite, in order to highlight the concomitant occurrence of these conditions and the potential adverse effects of anti-snake venom (ASV). A 35-year-old male was bitten by a viper at seventeen thirty hours, and was started on ASV. Two days following treatment he experienced sudden onset redness and painful diminution of vision in both eyes (OU). On examination, the patient's vis...
Schneider, Francisco S; Starling, Maria C; Duarte, Clara G; Machado de Avila, Ricardo; Kalapothakis, Evanguedes; Silva Suarez, Walter; Tintaya, Benigno; Flores Garrido, Karin; Seraylan Ormachea, Silvia; Yarleque, Armando; Bonilla, César; Chávez-Olórtegui, Carlos
Bothrops andianus is a venomous snake found in the area of Machu Picchu (Peru). Its venom is not included in the antigenic pool used for production of the Peruvian anti-bothropic anti-venom. B. andianus venom can elicit many biological effects such as hemorrhage, hemolysis, proteolytic activity and lethality. The Peruvian anti-bothropic anti-venom displays consistent cross-reactivity with B. andianus venom, by ELISA and Western Blotting and is also effective in neutralizing the venom's toxic activities. Copyright © 2012 Elsevier Ltd. All rights reserved.
These presynaptically acting toxins exhibit phospholipase A;. activity. . Cardiotoxins which cause augmentation of myocardial contractions at low concentration have been identified from cobra venoms . Crotamine rattle snake venoms have a specific and unique effect on the sodium channel of excitable membrane .
Tanaka, Gabriela D; Furtado, Maria de Fátima D; Portaro, Fernanda C V; Sant'Anna, Osvaldo Augusto; Tambourgi, Denise V
Micrurus snake bites can cause death by muscle paralysis and respiratory arrest, few hours after envenomation. The specific treatment for coral snake envenomation is the intravenous application of heterologous antivenom and, in Brazil, it is produced by horse immunization with a mixture of M. corallinus and M. frontalis venoms, snakes that inhabit the South and Southeastern regions of the country. However, this antivenom might be inefficient, considering the existence of intra- and inter-specific variations in the composition of the venoms. Therefore, the aim of the present study was to investigate the toxic properties of venoms from nine species of Micrurus: eight present in different geographic regions of Brazil (M. frontalis, M. corallinus, M. hemprichii, M. spixii, M. altirostris, M. surinamensis, M. ibiboboca, M. lemniscatus) and one (M. fulvius) with large distribution in Southeastern United States and Mexico. This study also analyzed the antigenic cross-reactivity and the neutralizing potential of the Brazilian coral snake antivenom against these Micrurus venoms. Analysis of protein composition and toxicity revealed a large diversity of venoms from the nine Micrurus species. ELISA and Western blot assays showed a varied capability of the therapeutic antivenom to recognize the diverse species venom components. In vivo and in vitro neutralization assays indicated that the antivenom is not able to fully neutralize the toxic activities of all venoms. These results indicate the existence of a large range of both qualitative and quantitative variations in Micrurus venoms, probably reflecting the adaptation of the snakes from this genus to vastly dissimilar habitats. The data also show that the antivenom used for human therapy in Brazil is not fully able to neutralize the main toxic activities present in the venoms from all Micrurus species occurring in the country. It suggests that modifications in the immunization scheme, with the inclusion of other venoms in the
Gabriela D Tanaka
Full Text Available BACKGROUND: Micrurus snake bites can cause death by muscle paralysis and respiratory arrest, few hours after envenomation. The specific treatment for coral snake envenomation is the intravenous application of heterologous antivenom and, in Brazil, it is produced by horse immunization with a mixture of M. corallinus and M. frontalis venoms, snakes that inhabit the South and Southeastern regions of the country. However, this antivenom might be inefficient, considering the existence of intra- and inter-specific variations in the composition of the venoms. Therefore, the aim of the present study was to investigate the toxic properties of venoms from nine species of Micrurus: eight present in different geographic regions of Brazil (M. frontalis, M. corallinus, M. hemprichii, M. spixii, M. altirostris, M. surinamensis, M. ibiboboca, M. lemniscatus and one (M. fulvius with large distribution in Southeastern United States and Mexico. This study also analyzed the antigenic cross-reactivity and the neutralizing potential of the Brazilian coral snake antivenom against these Micrurus venoms. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of protein composition and toxicity revealed a large diversity of venoms from the nine Micrurus species. ELISA and Western blot assays showed a varied capability of the therapeutic antivenom to recognize the diverse species venom components. In vivo and in vitro neutralization assays indicated that the antivenom is not able to fully neutralize the toxic activities of all venoms. CONCLUSION: These results indicate the existence of a large range of both qualitative and quantitative variations in Micrurus venoms, probably reflecting the adaptation of the snakes from this genus to vastly dissimilar habitats. The data also show that the antivenom used for human therapy in Brazil is not fully able to neutralize the main toxic activities present in the venoms from all Micrurus species occurring in the country. It suggests that
Tanaka, Gabriela D.; Furtado, Maria de Fátima D.; Portaro, Fernanda C. V.; Sant'Anna, Osvaldo Augusto; Tambourgi, Denise V.
Background Micrurus snake bites can cause death by muscle paralysis and respiratory arrest, few hours after envenomation. The specific treatment for coral snake envenomation is the intravenous application of heterologous antivenom and, in Brazil, it is produced by horse immunization with a mixture of M. corallinus and M. frontalis venoms, snakes that inhabit the South and Southeastern regions of the country. However, this antivenom might be inefficient, considering the existence of intra- and inter-specific variations in the composition of the venoms. Therefore, the aim of the present study was to investigate the toxic properties of venoms from nine species of Micrurus: eight present in different geographic regions of Brazil (M. frontalis, M. corallinus, M. hemprichii, M. spixii, M. altirostris, M. surinamensis, M. ibiboboca, M. lemniscatus) and one (M. fulvius) with large distribution in Southeastern United States and Mexico. This study also analyzed the antigenic cross-reactivity and the neutralizing potential of the Brazilian coral snake antivenom against these Micrurus venoms. Methodology/Principal Findings Analysis of protein composition and toxicity revealed a large diversity of venoms from the nine Micrurus species. ELISA and Western blot assays showed a varied capability of the therapeutic antivenom to recognize the diverse species venom components. In vivo and in vitro neutralization assays indicated that the antivenom is not able to fully neutralize the toxic activities of all venoms. Conclusion These results indicate the existence of a large range of both qualitative and quantitative variations in Micrurus venoms, probably reflecting the adaptation of the snakes from this genus to vastly dissimilar habitats. The data also show that the antivenom used for human therapy in Brazil is not fully able to neutralize the main toxic activities present in the venoms from all Micrurus species occurring in the country. It suggests that modifications in the
C. F. S. Amaral
Full Text Available This paper reports two cases of afibrinogenemia with normal platelet count following Crotalus durissus terrificus, snake bite Both patients presented high output acute renal failure and case two also had increased blood levels of CPK and LDH compatible with the diagnosis of rhabdomyolysis. Case one was given an unknown amount of antivenom and was treated with epsilonaminocaproic acid and a fresh whole blood transfusion and showed recovery of the coagulation disturbance 40 hours following these measures. Case two was given an adequate amount of crotalide antivenom and the coagulation tests performed 12 hours later showed a normal partial thromboplastin time and fibrinogen 86 mg/100ml. Case one presented no haemorrhagic disturbances. Case two presented persistent bleeding following venopuncture and after removal of impetigo crust in the legs. Acute renal failure was treated conservatively and both patients were discharged from the hospital with recovery of the renal function.
Norris, Robert L; Pfalzgraf, Robert R; Laing, Gavin
We report the first documented death due to a coral snake (Micrurus species) in the United States (U.S.) in over 40 years. The victim failed to seek medical care following the bite of an eastern coral snake (Micrurus fulvius) and succumbed within hours. Post-mortem proof of envenomation was obtained using an ELISA (enzyme-linked immunosorbent assay) developed specifically for this investigation. U.S. coral snakes are briefly reviewed in terms of their venom compositions, their clinical effects, and proper pre-hospital and hospital management. The clinical significance of the impending absence of commercially available antivenom for coral snake bites in the U.S. is highlighted.
Mirtschin, Peter J; Dunstan, Nathan; Hough, Ben; Hamilton, Ewan; Klein, Sharna; Lucas, Jonathan; Millar, David; Madaras, Frank; Nias, Timothy
The wet and dry venom yields for most Australian native dangerous snakes and a number of non-Australian species are presented. Snakes from the Pseudonaja genus yielded higher than previously published amounts and suggest reconsideration be given to increasing the volume of antivenom in each vial. Higher percentage solids were obtained from venoms from the 4 cobra species (Naja) and Pseudechis genus included in this series.
Waheed, Humera; Moin, Syed F; Choudhary, M I
Snakes are fascinating creatures and have been residents of this planet well before ancient humans dwelled the earth. Venomous snakes have been a figure of fear, and cause notable mortality throughout the world. The venom constitutes families of proteins and peptides with various isoforms that make it a cocktail of diverse molecules. These biomolecules are responsible for the disturbance in fundamental physiological systems of the envenomed victim, leading to morbidity which can lead to death if left untreated. Researchers have turned these life-threatening toxins into life-saving therapeutics via technological advancements. Since the development of captopril, the first drug that was derived from bradykininpotentiating peptide of Bothrops jararaca, to the disintegrins that have potent activity against certain types of cancers, snake venom components have shown great potential for the development of lead compounds for new drugs. There is a continuous development of new drugs from snake venom for coagulopathy and hemostasis to anti-cancer agents. In this review, we have focused on different snake venom proteins / peptides derived drugs that are in clinical use or in developmental stages till to date. Also, some commonly used snake venom derived diagnostic tools along with the recent updates in this exciting field are discussed. Copyright© Bentham Science Publishers; For any queries, please email at firstname.lastname@example.org.
Tun-Pe; Aye-Aye-Myint; Warrell, D A; Tin-Myint
Venom, venom IgG and IgM antibody and total serum IgG levels following king cobra bites in two reptile handlers were measured by enzyme immunoassay. The patient in case 1 received antivenom while the patient in case 2 did not. Case 1 made a complete recovery following the bite and produced a high titre short-lived antibody. Venom antigen was not detected in the sample taken 11 hr after antivenom. Case 2 had experienced two recent minor king cobra bites and had received traditional immunization 4 weeks before the accident reported here. He had developed only local swelling and suffered no neurological symptoms. Venom antigen measured at 1.45 hr after the bite was 132 ng/ml; this rapidly fell to 45 ng/ml over the next 30 min, and was no longer detectable 14 hr after the bite. The pattern of venom IgG and IgM antibody responses in both cases was comparable, except that in case 2 the venom IgG peak was maintained for 13 days, compared with 1 day in case 1; in case 2 it subsequently fell to low levels 8 weeks after the bite. Venom IgM appeared 1 day after the bite, peaked at day 7-9, rapidly tailed off on day 12-16 and was then undetectable from day 20 onwards in both. Total IgG level remained within normal limits in both. It is possible that previous bites and recent immunization contributed to the boosting of the venom IgG response in case 2.
Margres, Mark J; Aronow, Karalyn; Loyacano, Jacob; Rokyta, Darin R
Snake venom is shaped by the ecology and evolution of venomous species, and signals of positive selection in toxins have been consistently documented, reflecting the role of venoms as an ecologically critical phenotype...
Limam, I; El Ayeb, M; Marrakchi, N
The biochemical and the pharmacological characterization of snake venoms revealed an important structural and functional polymorphism of proteins which they contain. Among them, snake venom metalloproteases (SVMPs) constitute approximatively 20 to 60% of the whole venom proteins. During the last decades, a significant progress was performed against structure studies and the biosynthesis of the SVMPs. Indeed, several metalloproteases were isolated and characterized against their structural and pharmacological properties. In this review, we report the most important properties concerning the classification, the structure of the various domains of the SVMPs as well as their biosynthesis and their activities as potential therapeutic agents.
O'Leary, M A; Maduwage, K; Isbister, G K
Immunoturbidimetry studies the phenomenon of immunoprecipitation of antigens and antibodies in solution, where there is the formation of large, polymeric insoluble immunocomplexes that increase the turbidity of the solution. We used immunoturbidimetry to investigate the interaction between commercial snake antivenoms and snake venoms, as well as cross-reactivity between different snake venoms. Serial dilutions of commercial snake antivenoms (100μl) in water were placed in the wells of a microtitre plate and 100μl of a venom solution (50μg/ml in water) was added. Absorbance readings were taken at 340nm every minute on a BioTek ELx808 plate reader at 37°C. Limits imposed were a 30minute cut-off and 0.004 as the lowest significant maximum increase. Reactions with rabbit antibodies were carried out similarly, except that antibody dilutions were in PBS. Mixing venom and antivenom/antibodies resulted in an immediate increase in turbidity, which either reached a maximum or continued to increase until a 30minute cut-off. There was a peak in absorbance readings for most Australian snake venoms mixed with the corresponding commercial antivenom, except for Pseudonaja textilis venom and brown snake antivenom. There was cross-reactivity between Naja naja venom from Sri Lanka and tiger snake antivenom indicated by turbidity when they were mixed. Mixing rabbit anti-snake antibodies with snake venoms resulted in increasing turbidity, but there was not a peak suggesting the antibodies were not sufficiently concentrated. The absorbance reading at pre-determined concentrations of rabbit antibodies mixed with different venoms was able to quantify the cross-reactivity between venoms. Indian antivenoms from two manufacturers were tested against four Sri Lankan snake venoms (Daboia russelli, N. naja, Echis carinatus and Bungarus caeruleus) and showed limited formation of immunocomplexes with antivenom from one manufacturer. The turbidity test provides an easy and rapid way to compare
Weinstein, Scott A; Keyler, Daniel E
A case of clinically significant local envenoming resulting from a bite inflicted by a Western hognose snake, Heterodon nasicus, is described. The patient was bitten while offering a juvenile mouse to a captive snake. The snake maintained a grip on the patient's arm (left anticubital fossa) for several minutes. The bite resulted in marked edema, ecchymoses, lymphadenopathy, cutaneous signs suggestive of mild cellulitis and blister formation. There were no systemic effects. Recovery was complete after approximately five months. Several documented Heterodon sp. bites with significant clinical effects are reviewed. This common xenodontine colubrid must be considered capable of inflicting medically significant bites. It is currently unclear whether the pathological changes associated with these bites are due to specific Duvernoy's secretion components, Type I hypersensitivity or a combination of these. The influence of the feeding response on the severity of clinical effects is considered as is the discrepancy between experimentally verified pharmacological activities of Duvernoy's secretions from Heterodon sp. and medical sequelae of documented bites. Although hognose snakes may uncommonly produce medically significant bites, they should not be considered dangerous or venomous. Captive specimens should be handled carefully, particularly when offered food.
Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.
Advances in the last decade combining transcriptomics with established proteomics methods have made possible rapid identification and quantification of protein families in snake venoms. Although over 100 studies have been published, the value of this information is increased when it is collated, allowing rapid assimilation and evaluation of evolutionary trends, geographical variation, and possible medical implications. This review brings together all compositional studies of snake venom proteomes published in the last decade. Compositional studies were identified for 132 snake species: 42 from 360 (12%) Elapidae (elapids), 20 from 101 (20%) Viperinae (true vipers), 65 from 239 (27%) Crotalinae (pit vipers), and five species of non-front-fanged snakes. Approximately 90% of their total venom composition consisted of eight protein families for elapids, 11 protein families for viperines and ten protein families for crotalines. There were four dominant protein families: phospholipase A2s (the most common across all front-fanged snakes), metalloproteases, serine proteases and three-finger toxins. There were six secondary protein families: cysteine-rich secretory proteins, l-amino acid oxidases, kunitz peptides, C-type lectins/snaclecs, disintegrins and natriuretic peptides. Elapid venoms contained mostly three-finger toxins and phospholipase A2s and viper venoms metalloproteases, phospholipase A2s and serine proteases. Although 63 protein families were identified, more than half were present in snake species studied and always in low abundance. The importance of these minor component proteins remains unknown. PMID:28927001
Tripathy, S; Routray, P K; Mohapatra, A K; Mohapatra, M; Dash, S C
Russell's viper is a commonly encountered venomous snake in India. Morbidity and mortality following envenomation and the treatment thereof are frequent. We report a rarely seen complication after a treated Russell's viper bite. A 36-year-old male farmer received 30 vials polyvalent anti-snake venom after a viper bite to his right leg. Improvement in initial hematemesis and circulatory shock was followed by acute renal failure managed with regular hemodialysis. He displayed no abnormalities on neurological examination at admission. Fourth day onwards his neurologic status started deteriorating with development of behavioral abnormalities, hemi-spatial neglect of left upper limb, paralysis of left facial nerve, left upper limb, and right lower limb. Acute disseminated encephalomyelitis was confirmed on magnetic resonance imaging (MRI) of brain with typical spectroscopic characteristics. High dose methyl prednisolone was administered and a rapid recovery followed. Russell's viper bite followed by treatment with antivenom may be complicated by the development of immune complex mediated demyelination and development of acute disseminated encephalomyelitis. MRI spectroscopy helps in early identification of demyelination and in a definite diagnosis. Treatment with corticosteroids was associated with resolution of symptoms in this case.
Ushanandini, S; Nagaraju, S; Harish Kumar, K; Vedavathi, M; Machiah, D K; Kemparaju, K; Vishwanath, B S; Gowda, T V; Girish, K S
In Indian traditional medicine, various plants have been used widely as a remedy for treating snake bites. The aim of this study was to evaluate the effect of Tamarindus indica seed extract on the pharmacological as well as the enzymatic effects induced by V. russelli venom. Tamarind seed extract inhibited the PLA(2), protease, hyaluronidase, l-amino acid oxidase and 5'-nucleotidase enzyme activities of venom in a dose-dependent manner. These are the major hydrolytic enzymes responsible for the early effects of envenomation, such as local tissue damage, inflammation and hypotension. Furthermore, the extract neutralized the degradation of the Bbeta chain of human fibrinogen and indirect hemolysis caused by venom. It was also observed that the extract exerted a moderate effect on the clotting time, prolonging it only to a small extent. Edema, hemorrhage and myotoxic effects including lethality, induced by venom were neutralized significantly when different doses of the extract were preincubated with venom before the assays. On the other hand, animals that received extract 10 min after the injection of venom were protected from venom induced toxicity. Since it inhibits hydrolytic enzymes and pharmacological effects, it may be used as an alternative treatment to serum therapy and, in addition, as a rich source of potential inhibitors of PLA(2), metalloproteinases, serine proteases, hyaluronidases and 5 cent-nucleotidases, the enzymes involved in several physiopathological human and animal diseases. Copyright 2006 John Wiley & Sons, Ltd.
Full Text Available Poisoning from snake venom in animals is an emergency which requires immediate attention or otherwise, the delayed and inadequate treatment leads to untoward consequences and death. The present paper describes a case of venomous snakebite in a brown bear cub (Ursus arctos L. and its therapeutic management. The brown bear cub of which was found alone on the slopes of a mountain in the southwest part of the country was presented to the peripheral veterinary practice in Ohrid with a history of dullness, disorientation and excessive swelling around the left forepaw. It was diagnosed for snakebite based on the history and physical examination. The hematological parameters showed reduced values of hemoglobin, packed cell volume and increased total leukocyte count. The biochemical values showed elevated levels of alanine aminotransferase and creatinine. After immobilization of the animal, the treatment was conducted with fluids, corticosteroid and broad spectrum antibiotic with careful monitoring. Despite the treatment which was initiated immediately, it was only partially effective, and the animal died one hour after the beginning of its course. Poisonous snakes are common in the mountainous part of Macedonia and, just like humans, wild bears especially their cubs are susceptible to the deadly venom of some species. The severity of the reaction to snake venom and prognosis in animals depends on a number of factors: on the type and species of snake, on how much venom was injected, on the location of the bite, on the age, health and body weight of the animal and crucially, the time interval between the snakebite and the application of the treatment.
Seddik, Salwa S; Wanas, Soheir; Helmy, Madiha H; Hashem, Mohamed
This study was performed to assess the ability of polyvalent snake venom anti-serum, produced by the Egyptian Organization for Biological Products & Vaccines (VACSERA), to neutralize several toxic activities of snake venoms, not only of those included in the antivenom mixture, but also some additional venoms of snakes from Egyptian, African, and Middle Eastern habitats. In general, the results revealed that polyvalent snake venom anti-serum from VACSERA is highly effective in neutralizing Egyptian snake venoms, especially Naja haje, Naja nigricolles, Naja pallida, Cerastes cerastes, Cerastes cerastes cerastes, Cerastes vipera, Pseudocerastes persicus fieldi, and Walterinnisia egyptia. The antivenom was also effective against Naja haje, Walterinnisia egyptia, and Bites aritans from Saudi Arabia. High activity was obtained against venoms from Naja haje, Naja nigricolles, and Naja pallida of Sudan, as well as the African Naja melanoleuca, Naja mossambica, Naja naja oxiana, Bites gabonica, and Vipera lebetina. Only moderate effectiveness was obtained with Echis coloratus and Echis carinatus, and the polyvalent antiserum was ineffective against the venom of Naja nivea.
Choo Hock Tan
Full Text Available Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beaked sea snake (Hydrophis schistosus, formerly known as Enhydrina schistosa and the spine-bellied sea snake (Hydrophis curtus, formerly known as Lapemis curtus or Lapemis hardwickii are two commonly encountered species. Australian CSL sea snake antivenom is the definitive treatment for sea snake envenomation; it is unfortunately extremely costly locally and is not widely available or adequately stocked in local hospitals. This study investigated the cross-neutralizing potential of three regionally produced anti-cobra antivenoms against the venoms of Malaysian H. schistosus and H. curtus. All three antivenoms conferred paraspecific protection from sea snake venom lethality in mice, with potency increasing in the following order: Taiwan bivalent antivenom < Thai monocled cobra monovalent antivenom < Thai neuro polyvalent antivenom (NPAV. NPAV demonstrated cross-neutralizing potencies of 0.4 mg/vial for H. schistosus venom and 0.8 mg/vial for H. curtus, which translates to a dose of less than 20 vials of NPAV to neutralize an average amount of sea snake venom per bite (inferred from venom milking. The cross-neutralization activity was supported by ELISA cross-reactivity between NPAV and the venoms of H. schistosus (58.4% and H. curtus (70.4%. These findings revealed the potential of NPAV as a second-line treatment for sea snake envenomation in the region. Further profiling of the cross-neutralization activity should address the antivenomic basis using purified toxin-based assays.
Tan, Choo Hock; Tan, Nget Hong; Tan, Kae Yi; Kwong, Kok Onn
Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beaked sea snake (Hydrophis schistosus, formerly known as Enhydrina schistosa) and the spine-bellied sea snake (Hydrophis curtus, formerly known as Lapemis curtus or Lapemis hardwickii) are two commonly encountered species. Australian CSL sea snake antivenom is the definitive treatment for sea snake envenomation; it is unfortunately extremely costly locally and is not widely available or adequately stocked in local hospitals. This study investigated the cross-neutralizing potential of three regionally produced anti-cobra antivenoms against the venoms of Malaysian H. schistosus and H. curtus. All three antivenoms conferred paraspecific protection from sea snake venom lethality in mice, with potency increasing in the following order: Taiwan bivalent antivenom < Thai monocled cobra monovalent antivenom < Thai neuro polyvalent antivenom (NPAV). NPAV demonstrated cross-neutralizing potencies of 0.4 mg/vial for H. schistosus venom and 0.8 mg/vial for H. curtus, which translates to a dose of less than 20 vials of NPAV to neutralize an average amount of sea snake venom per bite (inferred from venom milking). The cross-neutralization activity was supported by ELISA cross-reactivity between NPAV and the venoms of H. schistosus (58.4%) and H. curtus (70.4%). These findings revealed the potential of NPAV as a second-line treatment for sea snake envenomation in the region. Further profiling of the cross-neutralization activity should address the antivenomic basis using purified toxin-based assays. PMID:25690691
Chu, Edward R; Weinstein, Scott A; White, Julian; Warrell, David A
Venom ophthalmia caused by venoms of spitting elapid and other snakes: report of ten cases with review of epidemiology, clinical features, pathophysiology and management. Chu, ER, Weinstein, SA, White, J and Warrell, DA. Toxicon XX:xxx-xxx. We present ten cases of ocular injury following instillation into the eye of snake venoms or toxins by spitting elapids and other snakes. The natural history of spitting elapids and the toxinology of their venoms are reviewed together with the medical effects and management of venom ophthalmia in humans and domestic animals including both direct and allergic effects of venoms. Although the clinical features and management of envenoming following bites by spitting elapids (genera Naja and Hemachatus) are well documented, these snakes are also capable of "spraying" venom towards the eyes of predators, a defensive strategy that causes painful and potentially blinding ocular envenoming (venom ophthalmia). Little attention has been given to the detailed clinical description, clinical evolution and efficacy of treatment of venom ophthalmia and no clear management guidelines have been formulated. Knowledge of the pathophysiology of ocular envenoming is based largely on animal studies and a limited body of clinical information. A few cases of ocular exposure to venoms from crotaline viperids have also been described. Venom ophthalmia often presents with pain, hyperemia, blepharitis, blepharospasm and corneal erosions. Delay or lack of treatment may result in corneal opacity, hypopyon and/or blindness. When venom is "spat" into the eye, cranial nerve VII may be affected by local spread of venom but systemic envenoming has not been documented in human patients. Management of venom ophthalmia consists of: 1) urgent decontamination by copious irrigation 2) analgesia by vasoconstrictors with weak mydriatic activity (e.g. epinephrine) and limited topical administration of local anesthetics (e.g. tetracaine) 3) exclusion of corneal abrasions
Hourieh Esmaeili Jahromi
Full Text Available Background:Envenomation by Macrovipera lebetina (M. lebetina is characterized by prominent local tissue damage, hemorrhage, abnormalities in the blood coagulation system, necrosis, and edema. However, the main cause of death after a bite by M. lebetina has been attributed to acute renal failure (ARF. It is unclear whether the venom components have a direct or indirect action in causing ARF. To investigate this point, we looked at the in vitro effect of M. lebetina crude venom, using cultured human embryonic kidney (HEK-293 mono layers as a model. Methods: The effect of M. lebetina snake venom on HEK-293 growth inhibition was determined by the MTT assay and the neutral red uptake assay. The integrity of the cell membrane through LDH release was measured with the Cytotoxicity Detection Kit. Morphological changes in HEK-293 cells were also evaluated using an inverted microscope. Results: In the MTT assay, crude venom showed a significant cytotoxic effect on HEK-293 cells at 24 hours of exposure and was confirmed by the neutral red assay. Also, at 24 hours exposure, crude venom caused a non-significant increase in LDH activity of the culture medium at concentrations above 20 μg/ml. Various morphological abnormalities were observed in cells exposed to the venom and showed loss of their common polygonal shape, appearing as several roughly rounded cells of variable size. The M. lebetina crude venom induced detachment of cells from the plate. Conclusion: Based on the results obtained in this study, it can be concluded that the Iranian snake M. lebetina venom causes a cytotoxic effect on kidney tissue not by necrotic mechanism but rather by secondary effects, including hypotension, hemolysis, hemoglobinuria, rhabdomyolysis, myoglobinuria and disseminated intravascular coagulation (DIC, which may lead to ARF.
Hayat, Atif Sitwat; Khan, Abdul Haque; Shaikh, Tariq Zaffar; Ghouri, Rafi Ahmed; Shaikh, Naila
Envenoming resulting from snakebites is an important public health hazard in many regions. It is common in rural areas not to delay access to life saving anti-venom. The objectives of this study were to know about common types of snakes in local areas, clinical features in snakebite victims, complications in snakebite case, and mortality rate in snakebite victims in rural Sindh. This descriptive study was conducted at 4 medical wards of Liaquat University Hospital Hyderabad/Jamshoro, Sindh from 1st January 2006 to December 2006. One hundred cases with history of snakebite were analysed. Both genders were included in study. Patients with history of trauma, insect bite or thorn prick were excluded from the study. Clotting time (CT) was the main bedside procedure, to assess the degree of envenomation. One hundred (100) cases from both genders, from 8 to 55 years age were reviewed. There were 57 (95%) viper bites (haemotoxic) having haemostatic abnormalities and 3 (5%) elapid (neurotoxic) bites presented with neuroparalytic symptoms. Most cases were from Tando Mohammad Khan and Hyderabad (rural) districts of Sindh. All viotims had localized oedema at the site of bite. Fang/teeth marks were noted in (90%) cases. Majority (80%) were bitten on the legs below knee. Some 40% of the cases of snakebite occurred when the patient was asleep. Urban to rural ratio was 1:4.5 and male to female ratio was 4:1. Mean time to arrival at our hospital after the bite was 3 hours and mean duration of hospital stay was 4 days. One patient had acute renal failure (ARF) and disseminated intravascular coagulation (DIC), 3% cases of elapid bites were shifted to ICU for assisted ventilation, 4 patients (5.5%) had adverse effects after anti-venom administration and needed intravenous hydrocortisone, promethazine and subcutaneous adrenaline. The average dose of anti-venom was 60 vials for viper bites and 10 vials for elapid bites. Overall mortality rate was 4%. Snakebites are common in the rural
Kumar, Praveen K; Ahuja, Shashi; Kumar, Praveen S
The authors wish to report a case of bilateral acute anterior uveitis and optic disc edema following a hemotoxic snake bite, in order to highlight the concomitant occurrence of these conditions and the potential adverse effects of anti-snake venom (ASV). A 35-year-old male was bitten by a viper at seventeen thirty hours, and was started on ASV. Two days following treatment he experienced sudden onset redness and painful diminution of vision in both eyes (OU). On examination, the patient's visual acuity (VA) in OU was 20/200. Examination revealed fresh keratic precipitates, cells, and flare in the anterior chamber (AC), posterior synechiae, sluggish and ill-sustained pupillary reaction, and hyperemic, edematous disc with blurred margins in OU. He was started on topical steroids, cycloplegics and intravenous methylprednisolone. Following treatment, the patient showed improvement and was continued on topical medications and oral prednisolone tapered over 3 weeks, after which VA OU improved, the AC showed no cells and flare and disc edema resolved. Uveitis and optic disc edema in snake bite can either be due to the direct toxic effects of the venom or the effect of ASV. Steroids have a beneficial role in the management of these symptoms.
Redsted Rasmussen, Arne; Sanders, Kate L.
The status of taxonomy and venom in sea snakesArne R Rasmussen1, Kate L Sanders21 The Royal Danish Academy of Fine Arts, School of Architecture, Design & Conservation, Copenhagen, Denmark2 School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia 5000, Australia......Sea snakes form two aquatic groups of snakes with a flat vertically paddle-form tail (sea kraits and viviparous sea snakes). Sea snakes belong to the same family Elapidae, which also includes the terrestrial mambas, cobra, kraits, taipan and brown snake. All elapids are characterized by the anterior position...... of the poison-fangs on the maxillary bone (proteroglyphous). Globally there are some 70 species of sea snake found in the tropical and subtropical waters of the Indian Ocean and the Pacific Ocean. Most species are found in the Indo-Malayan Archipelago, the China Sea, Indonesia, and the Australian region...
Boldrini-França, Johara; Cologna, Camila Takeno; Pucca, Manuela Berto; Bordon, Karla de Castro Figueiredo; Amorim, Fernanda Gobbi; Anjolette, Fernando Antonio Pino; Cordeiro, Francielle Almeida; Wiezel, Gisele Adriano; Cerni, Felipe Augusto; Pinheiro-Junior, Ernesto Lopes; Shibao, Priscila Yumi Tanaka; Ferreira, Isabela Gobbo; de Oliveira, Isadora Sousa; Cardoso, Iara Aimê; Arantes, Eliane Candiani
Snake venoms present a great diversity of pharmacologically active compounds that may be applied as research and biotechnological tools, as well as in drug development and diagnostic tests for certain diseases. The most abundant toxins have been extensively studied in the last decades and some of them have already been used for different purposes. Nevertheless, most of the minor snake venom protein classes remain poorly explored, even presenting potential application in diverse areas. The main difficulty in studying these proteins lies on the impossibility of obtaining sufficient amounts of them for a comprehensive investigation. The advent of more sensitive techniques in the last few years allowed the discovery of new venom components and the in-depth study of some already known minor proteins. This review summarizes information regarding some structural and functional aspects of low abundant snake venom proteins classes, such as growth factors, hyaluronidases, cysteine-rich secretory proteins, nucleases and nucleotidases, cobra venom factors, vespryns, protease inhibitors, antimicrobial peptides, among others. Some potential applications of these molecules are discussed herein in order to encourage researchers to explore the full venom repertoire and to discover new molecules or applications for the already known venom components. Copyright © 2016. Published by Elsevier B.V.
Seifert, Steven A; Boyer, Leslie V; Benson, Blaine E; Rogers, Jody J
Differences in victim demographics, clinical effects, managements, and outcomes among native viperid (rattlesnake, copperhead, and cottonmouth) and elapid (coral snake) species have not been systematically characterized. The database of the American Association of Poison Control Centers from 2001 through 2005 was analyzed. Between 2001 and 2005, there were 23,676 human exposures (average = 4,735/year) to native venomous snakes in the United States reported to U.S. poison centers in all states except Hawaii: 98% were to viperid snakes and 2% to elapids. Overall, 77% of victims were male, 70% were adults >20 years, and 12% were aged less than 10 years. Sixty-five cases involved pregnant women, with rattlesnake bites resulting in moderate or greater effects in over 70%. The overall hospital admission rate was 53%. Outcomes were generally more severe with rattlesnake and copperhead envenomations and in children coral snakebites result in similar hospital admission rates.
Lomonte, Bruno; Fernández, Julián; Sanz, Libia; Angulo, Yamileth; Sasa, Mahmood; Gutiérrez, José María; Calvete, Juan J
In spite of its small territory of ~50,000km(2), Costa Rica harbors a remarkably rich biodiversity. Its herpetofauna includes 138 species of snakes, of which sixteen pit vipers (family Viperidae, subfamily Crotalinae), five coral snakes (family Elapidae, subfamily Elapinae), and one sea snake (Family Elapidae, subfamily Hydrophiinae) pose potential hazards to human and animal health. In recent years, knowledge on the composition of snake venoms has expanded dramatically thanks to the development of increasingly fast and sensitive analytical techniques in mass spectrometry and separation science applied to protein characterization. Among several analytical strategies to determine the overall protein/peptide composition of snake venoms, the methodology known as 'snake venomics' has proven particularly well suited and informative, by providing not only a catalog of protein types/families present in a venom, but also a semi-quantitative estimation of their relative abundances. Through a collaborative research initiative between Instituto de Biomedicina de Valencia (IBV) and Instituto Clodomiro Picado (ICP), this strategy has been applied to the study of venoms of Costa Rican snakes, aiming to obtain a deeper knowledge on their composition, geographic and ontogenic variations, relationships to taxonomy, correlation with toxic activities, and discovery of novel components. The proteomic profiles of venoms from sixteen out of the 22 species within the Viperidae and Elapidae families found in Costa Rica have been reported so far, and an integrative view of these studies is hereby presented. In line with other venomic projects by research groups focusing on a wide variety of snakes around the world, these studies contribute to a deeper understanding of the biochemical basis for the diverse toxic profiles evolved by venomous snakes. In addition, these studies provide opportunities to identify novel molecules of potential pharmacological interest. Furthermore, the
Full Text Available In this study, we evaluate 25 cases who were admitted to the emergency service and transferred to the intensive care unit subsequently due to snakebite, prospectively. Clinical courses, toxic effects, complications and treatment approaches were aimed to be presented. Among the patients, 16 were female and 9 were male; the mean age was 42.1 (17-74 years. It was determined that all the cases were admitted to the hospital during working in the field in Eastern Anatolia Region, between the months of May and June, and between the hours of 15:00 to 18:00. When the cases were considered in terms of bitten body part, 15 were bitten from upper extremity and 10 were bitten from lower extremity. Within an hour the patients were admitted to a health facility with the complaints of nausea, pain, numbness, swelling and redness, and patients were transferred to emergency unit approximately within 1 hour (0.5 to 2 hours following the first intervention. Tetanus immunization is administered in all cases as the first intervention. Antivenom was administered to the 9 (36% of the patients in whom steroid, antihistamine and prophylactic antibiotic therapy was given in the intensive care unit. Under the control of infection clinic, antibiotic therapy was initiated to 13 (52% patients in who cellulitis, abscess, lymphedema and compartment syndrome were developed. Healing was observed approximately within 4 days (2-6 days and recovery was observed in all the cases. Patients admitted due to snake bites should be followed closely for at least 6 to 8 hours. According to the patient’s clinical condition and laboratory test results, early intervention therapy should be regulated and antivenom therapy should be administered in the presence of systemic symptoms.
Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods:The details of all patients with snake bite admitted to a tertiary teaching care hospital from. 2010 to 2012 were ...
Background: A snake bite is an injury caused by a bite from a snake, often resulting in puncture wounds, amputations and sometimes envenomation. Envenoming resulting from snake bite is a particularly important public health problem in rural areas of tropical and sub-tropical countries in Africa. This paper reports the ...
The use of first aid measures in the management of snake bite by patients in rural communities in Africa is a popular practice. Records of 103 snake bite patients admitted at Zamko Comprehensive Health Centre, were retrieved and reviewed. 84 (81.6%) of the 103 cases with snake bite used first aid measures. Common first ...
Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods: The details of all patients with snake bite admitted to a tertiary teaching care hospital from 2010 to 2012 were ...
Reyes-Velasco, Jacobo; Card, Daren C; Andrew, Audra L; Shaney, Kyle J; Adams, Richard H; Schield, Drew R; Casewell, Nicholas R; Mackessy, Stephen P; Castoe, Todd A
Snake venom gene evolution has been studied intensively over the past several decades, yet most previous studies have lacked the context of complete snake genomes and the full context of gene expression across diverse snake tissues. We took a novel approach to studying snake venom evolution by leveraging the complete genome of the Burmese python, including information from tissue-specific patterns of gene expression. We identified the orthologs of snake venom genes in the python genome, and conducted detailed analysis of gene expression of these venom homologs to identify patterns that differ between snake venom gene families and all other genes. We found that venom gene homologs in the python are expressed in many different tissues outside of oral glands, which illustrates the pitfalls of using transcriptomic data alone to define "venom toxins." We hypothesize that the python may represent an ancestral state prior to major venom development, which is supported by our finding that the expansion of venom gene families is largely restricted to highly venomous caenophidian snakes. Therefore, the python provides insight into biases in which genes were recruited for snake venom systems. Python venom homologs are generally expressed at lower levels, have higher variance among tissues, and are expressed in fewer organs compared with all other python genes. We propose a model for the evolution of snake venoms in which venom genes are recruited preferentially from genes with particular expression profile characteristics, which facilitate a nearly neutral transition toward specialized venom system expression. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: email@example.com.
Ibrahim, Nihal M; El-Kady, Ebtsam M
In the present study, we recognized progressively high immunological cross-reactivity between Pseudocerastes persicus fieldi (Pf) venom and six other medically important Egyptian snake venoms belonging to families Viperidae and Elapidae. Antibodies with a range of bonding strengths were shown to be involved in such cross-reactivity. Two strategies have been tried to access specificity; (i) using affinity purified species-specific anti-Pf antivenom antibodies, (ii) conducting the assay in the presence of ammonium thiocyanate (NH4SCN). The discrimination power of the prepared species-specific antivenom was demonstrated by its ability to detect Pf venom over a range of Pf concentrations (2.5 ng-2.5 μg) in a variety of body fluids. The assay could distinguish circulating Pf antigens from other viper antigens in the whole blood of experimentally envenomed mice. What seems promising in our work is the use of the chaotrope, NH4SCN, which renders the reaction medium more favorable for the specific homologous antigen-antibody interactions, primarily via preventing lower avid antibodies to share and, to a bit lesser extent, by decreasing non-specific absorbance signals frequently encountered with ELISA assays. The ELISA described herein may be useful for clinicians for identification of snake bites inflicted by Pf snake species. Balancing between specificity and sensitivity has to be considered for best results. Copyright © 2016 Elsevier Ltd. All rights reserved.
Van den Enden, E J; Van Gompel, A; Wijnants, H; Colebunders, R; Van den Ende, J
Every year there are hundreds of snake bites in Europe, but the main problems occur in tropical areas. Symptoms such as hemorrhages, paralysis and local necrosis vary according to the snake species. Inappropriate first aid should be avoided. Antitoxin should be administered if there are signs of poisoning. It is never too late to give antitoxin. Antitoxin can have a number of potentially very dangerous side-effects.
Vonk, F.J.; Casewell, N. R.; Henkel, C.V.; Heimberg, A. M.; Jansen, H.J.; McCleary, R.J.R.; Kerkkamp, H. M. E.; Vos, R. A.; Guerreiro, I.; Calvete, J. J.; Wüster, W; Woods, A E; Logan, J. M.; Harrison, R. A.; Castoe, T. A.
Snakes are limbless predators, and many species use venom to help overpower relatively large, agile prey. Snake venoms are complex protein mixtures encoded by several multilocus gene families that function synergistically to cause incapacitation. To examine venom evolution, we sequenced and interrogated the genome of a venomous snake, the king cobra (Ophiophagus hannah), and compared it, together with our unique transcriptome, microRNA, and proteome datasets from this species, with data from ...
Savage, Jay M.; Vial, James L.
Four species of venomous coral snakes (Micrurus) occur in Costa Rica. The single bicolor species, M. mipartitus has previously been defined as two subspecies; however, variations in diagnostic characters clemonstrate dinal shift that precludes recognition of geographic races.Presence of the tricolor M. clarki is concluded from but a single Costa Rican specimen, although the species is otherwise definitely known from adjacent areas in Panamá.Variation among tricolor coral snakes allied to M. n...
Bucaretchi, Fábio; Capitani, Eduardo Mello De; Vieira, Ronan José; Rodrigues, Cinthia K; Zannin, Marlene; Da Silva, Nelson J; Casais-e-Silva, Luciana L; Hyslop, Stephen
In the Americas, the main representatives of the family Elapidae are coral snakes of the genus Micrurus, of which 33 species are in Brazil. They are the smallest cause of venomous snakebite in Brazil. We analyzed literature reports of coral snake bites in Brazil from 1867 to 2014, and provide a brief review of case series and reports of coral snake bites in the Americas in general. Only reports with clinical descriptions of envenomation were included. The variables recorded included identification of the offending snake, patient's age, sex, bite site, clinical manifestations, treatment, including antivenom and anticholinesterase drugs, and general evolution of the cases. 30 published reports describing bites caused by Micrurus spp. in Brazil were identified and involved 194 distinct cases. Since no information on the clinical manifestations was available in 44 cases, the analysis was restricted to 25 reports (150 cases). Most patients were from southern (61.3%; primarily Santa Catarina state, 60%) and southeastern (20%) Brazil and were male (70.7%), with a median age of 27 years (interquartile interval = 18 to 40 years). The offending snakes were described in 59 cases (M. corallinus 36, M. frontalis 12, M. lemniscatus 5, M. hemprichi 2, M. filiformis 1, M. ibiboboca 1, M. spixii 1 and M. surinamensis 1); in 22 cases only the genus (Micrurus spp.) was reported. Of the 143 cases in which the bite site was recorded, most involved the hands (46.2%) and feet (26.6%). The main clinical features were local numbness/paresthesia (52.7%), local pain (48%), palpebral ptosis (33.3%), dizziness (26.7%), blurred vision (20.7%), weakness (20%), slight local edema (16%), erythema (16%), dysphagia (14.7%), dyspnea (11.3%), inability to walk (10.7%), myalgia (9.3%), salivation (8%) and respiratory failure (4.3%). Fang marks were described in 47.3% of cases and 14% of bites were classified as asymptomatic. A slight increase in total blood creatine kinase was reported in 3 children
van Genderen, P J J; Slobbe, L; Koene, H; Mastenbroek, R D L; Overbosch, D
To describe the incidence of venomous snakebites and the hospital treatment thereof (if any) amongst private individuals who keep venomous snakes as a hobby. Descriptive study. Private keepers of venomous snakes were invited via the social media Facebook, Hyves, Twitter, Google Plus, Linked In and two large discussion forums to fill in an online questionnaire on a purely voluntary and anonymous basis. In the period from 1 September 2012 to 31 December 2012, 86 questionnaires were completed by individuals who keep venomous snakes as a hobby. One-third of the venomous snake keepers stated that they had at some point been bitten by a venomous snake. Out of those, two-thirds needed hospital treatment and one-third of those bitten required at least one, sometimes more, doses of antiserum. The chances of being bitten increased the more venomous snakes a person kept. An inventory of the collections of venomous snakes being kept further revealed that no antiserum exists for 16 of the species, including for the most commonly held venomous snake, the coral cobra. Keeping venomous snakes as a hobby is not without danger. Although in the majority of snakebite cases no antiserum had to be administered, there is nevertheless a significant risk of morbidity and sequelae. Preventing snakebites in the first place remains the most important safety measure since there are no antiserums available for a substantial number of venomous snakes.
Bernardoni, Juliana L; Sousa, Leijiane F; Wermelinger, Luciana S; Lopes, Aline S; Prezoto, Benedito C; Serrano, Solange M T; Zingali, Russolina B; Moura-da-Silva, Ana M
Snake venom metalloproteinases (SVMPs) are major components in most viperid venoms that induce disturbances in the hemostatic system and tissues of animals envenomated by snakes. These disturbances are involved in human pathology of snake bites and appear to be essential for the capture and digestion of snake's prey and avoidance of predators. SVMPs are a versatile family of venom toxins acting on different hemostatic targets which are present in venoms in distinct structural forms. However, the reason why a large number of different SVMPs are expressed in some venoms is still unclear. In this study, we evaluated the interference of five isolated SVMPs in blood coagulation of humans, birds and small rodents. P-III class SVMPs (fractions Ic, IIb and IIc) possess gelatinolytic and hemorrhagic activities, and, of these, two also show fibrinolytic activity. P-I class SVMPs (fractions IVa and IVb) are only fibrinolytic. P-III class SVMPs reduced clotting time of human plasma. Fraction IIc was characterized as prothrombin activator and fraction Ic as factor X activator. In the absence of Ca2+, a firm clot was observed in chicken blood samples with fractions Ic, IIb and partially with fraction IIc. In contrast, without Ca2+, only fraction IIc was able to induce a firm clot in rat blood. In conclusion, functionally distinct forms of SVMPs were found in B. neuwiedi venom that affect distinct mechanisms in the coagulation system of humans, birds and small rodents. Distinct SVMPs appear to be more specialized to rat or chicken blood, strengthening the current hypothesis that toxin diversity enhances the possibilities of the snakes for hunting different prey or evading different predators. This functional diversity also impacts the complexity of human envenoming since different hemostatic mechanisms will be targeted by SVMPs accounting for the complexity of the response of humans to venoms.
Juliana L Bernardoni
Full Text Available Snake venom metalloproteinases (SVMPs are major components in most viperid venoms that induce disturbances in the hemostatic system and tissues of animals envenomated by snakes. These disturbances are involved in human pathology of snake bites and appear to be essential for the capture and digestion of snake's prey and avoidance of predators. SVMPs are a versatile family of venom toxins acting on different hemostatic targets which are present in venoms in distinct structural forms. However, the reason why a large number of different SVMPs are expressed in some venoms is still unclear. In this study, we evaluated the interference of five isolated SVMPs in blood coagulation of humans, birds and small rodents. P-III class SVMPs (fractions Ic, IIb and IIc possess gelatinolytic and hemorrhagic activities, and, of these, two also show fibrinolytic activity. P-I class SVMPs (fractions IVa and IVb are only fibrinolytic. P-III class SVMPs reduced clotting time of human plasma. Fraction IIc was characterized as prothrombin activator and fraction Ic as factor X activator. In the absence of Ca2+, a firm clot was observed in chicken blood samples with fractions Ic, IIb and partially with fraction IIc. In contrast, without Ca2+, only fraction IIc was able to induce a firm clot in rat blood. In conclusion, functionally distinct forms of SVMPs were found in B. neuwiedi venom that affect distinct mechanisms in the coagulation system of humans, birds and small rodents. Distinct SVMPs appear to be more specialized to rat or chicken blood, strengthening the current hypothesis that toxin diversity enhances the possibilities of the snakes for hunting different prey or evading different predators. This functional diversity also impacts the complexity of human envenoming since different hemostatic mechanisms will be targeted by SVMPs accounting for the complexity of the response of humans to venoms.
Full Text Available Venoms can deleteriously affect any physiological system reachable by the bloodstream, including directly interfering with the coagulation cascade. Such coagulopathic toxins may be anticoagulants or procoagulants. Snake venoms are unique in their use of procoagulant toxins for predatory purposes. The boomslang (Dispholidus typus and the twig snakes (Thelotornis species are iconic African snakes belonging to the family Colubridae. Both species produce strikingly similar lethal procoagulant pathologies. Despite these similarities, antivenom is only produced for treating bites by D. typus, and the mechanisms of action of both venoms have been understudied. In this study, we investigated the venom of D. typus and T. mossambicanus utilising a range of proteomic and bioactivity approaches, including determining the procoagulant properties of both venoms in relation to the human coagulation pathways. In doing so, we developed a novel procoagulant assay, utilising a Stago STA-R Max analyser, to accurately detect real time clotting in plasma at varying concentrations of venom. This approach was used to assess the clotting capabilities of the two venoms both with and without calcium and phospholipid co-factors. We found that T. mossambicanus produced a significantly stronger coagulation response compared to D. typus. Functional enzyme assays showed that T. mossambicanus also exhibited a higher metalloprotease and phospholipase activity but had a much lower serine protease activity relative to D. typus venom. The neutralising capability of the available boomslang antivenom was also investigated on both species, with it being 11.3 times more effective upon D. typus venom than T. mossambicanus. In addition to being a faster clotting venom, T. mossambicanus was revealed to be a much more complex venom composition than D. typus. This is consistent with patterns seen for other snakes with venom complexity linked to dietary complexity. Consistent with the
Calvete, Juan J
A deep understanding of the composition of venoms and of the principles governing the evolution of venomous systems is of applied importance for exploring the enormous potential of venoms as sources of chemical and pharmacological novelty but also to fight the dire consequences of snakebite envenomings. This goal is now within the reach of "omic" technologies. A central thesis developed in this essay is the view that making sense of the huge inventory of data gathered through "omic" approaches requires the integration of this information across the biological system. Key to this is the identification of evolutionary and ecological trends; without the evolutionary link, systems venomics is relegated to a set of miscellaneous facts. The interplay between chance and adaptation plays a central role in the evolution of biological systems (Monod, 1970). However, the evolution of venomous species and their venoms do not always follow the same course, and the identification of structural and functional convergences and divergences among venoms is often unpredictable by a phylogenetic hypothesis. Toxins sharing a structural fold present in venoms from phylogenetically distant snakes often share antigenic determinants. The deficit of antivenom supply in certain regions of the world can be mitigated in part through the optimized use of existing antivenoms, and through the design of novel broad-range polyspecific antivenoms. Proteomics-guided identification of evolutionary and immunoreactivity trends among homologous and heterologous venoms may aid in the replacement of the traditional geographic- and phylogenetic-driven hypotheses for antivenom production strategies by a more rationale approach based on a hypothesis-driven systems venomics approach. Selected applications of venomics and antivenomics for exploring the chemical space and immunological profile of venoms will illustrate the author's views on the impact these proteomics tools may have in the field of toxinology
Urra, Félix A; Pulgar, Rodrigo; Gutiérrez, Ricardo; Hodar, Christian; Cambiazo, Verónica; Labra, Antonieta
Philodryas chamissonis is a rear-fanged snake endemic to Chile. Its bite produces mild to moderate symptoms with proteolytic and anti-coagulant effects. Presently, the composition of the venom, as well as, the biochemical and structural characteristics of its toxins, remains unknown. In this study, we cloned and reported the first full-length sequences of five toxin-encoding genes from the venom gland of this species: Type III snake venom metalloprotease (SVMP), snake venom serine protease (SVSP), Cysteine-rich secretory protein (CRISP), α and β subunits of C-type lectin-like protein (CLP) and C-type natriuretic peptide (NP). These genes are highly expressed in the venom gland and their sequences exhibited a putative signal peptide, suggesting that these are components of the venom. These putative toxins had different evolutionary relationships with those reported for some front-fanged snakes, being SVMP, SVSP and CRISP of P. chamissonis closely related to the toxins present in Elapidae species, while NP was more related to those of Viperidae species. In addition, analyses suggest that the α and β subunits of CLP of P. chamissonis might have a α-subunit scaffold in common with Viperidae species, whose highly variable C-terminal region might have allowed the diversification in α and β subunits. Our results provide the first molecular description of the toxins possibly implicated in the envenomation of prey and humans by the bite of P. chamissonis. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available Ophidian envenomation accidents constitute a serious public health problem in many countries around the globe. Over 5 million such accident cases occur each year causing more than 100,000 deaths. In Africa, more than 20,000 deaths per year are registered while 400,000 envenomation victims retain severe and permanent functional sequelae. In Morocco, snakebites are frequent and of greater severity in children. They occur mostly in rural areas. The incidence of these bites remains poorly understood and vastly underestimated. The epidemiological data are not well known due to the absence of a national registry, whereas a significant proportion of envenomations receive only traditional treatment methods in non-medical intensive care. This prompted us to investigate the enzymatic and biological properties of venom biochemical constituents from two of the most dangerous snake venoms in Morocco: Cerastes cerastes (Cc and Macrovipera mauritanica (Mm. Also, we studied the immune cross-reactivity of Cc and Mm venoms in comparison to that of another important dangerous Moroccan viper, Bitis arietans (Ba, to identify the best candidates (venom or a mixture of venoms for producing the most efficient and protective antivenom. In the present study, we report a preliminary venom characterization of Cc and Mm and the cross-reactivity that may exist between their venoms and Ba. These venoms are known to be highly toxic and contain several proteins that differ by molecular weights. Interestingly, both Cc and Mm venoms are characterized by intense hemorrhagic and phospholipase A2 activities and their ability to degrade the α and γ chains of fibrinogen. They display very low proteolysis through the casein test. After injection into mice, Cc and Mm induce myonecrosis in skeletal muscles, which most likely reflects direct action of myotoxins and indirect action of hemorrhagic molecules present in these venoms. In mice, this myonecrosis diminishes serum creatine
Jesupret, Clémence; Baumann, Kate; Jackson, Timothy N W; Ali, Syed Abid; Yang, Daryl C; Greisman, Laura; Kern, Larissa; Steuten, Jessica; Jouiaei, Mahdokht; Casewell, Nicholas R; Undheim, Eivind A B; Koludarov, Ivan; Debono, Jordan; Low, Dolyce H W; Rossi, Sarah; Panagides, Nadya; Winter, Kelly; Ignjatovic, Vera; Summerhayes, Robyn; Jones, Alun; Nouwens, Amanda; Dunstan, Nathan; Hodgson, Wayne C; Winkel, Kenneth D; Monagle, Paul; Fry, Bryan Grieg
For over a century, venom samples from wild snakes have been collected and stored around the world. However, the quality of storage conditions for "vintage" venoms has rarely been assessed. The goal of this study was to determine whether such historical venom samples are still biochemically and pharmacologically viable for research purposes, or if new sample efforts are needed. In total, 52 samples spanning 5 genera and 13 species with regional variants of some species (e.g., 14 different populations of Notechis scutatus) were analysed by a combined proteomic and pharmacological approach to determine protein structural stability and bioactivity. When venoms were not exposed to air during storage, the proteomic results were virtually indistinguishable from that of fresh venom and bioactivity was equivalent or only slightly reduced. By contrast, a sample of Acanthophis antarcticus venom that was exposed to air (due to a loss of integrity of the rubber stopper) suffered significant degradation as evidenced by the proteomics profile. Interestingly, the neurotoxicity of this sample was nearly the same as fresh venom, indicating that degradation may have occurred in the free N- or C-terminus chains of the proteins, rather than at the tips of loops where the functional residues are located. These results suggest that these and other vintage venom collections may be of continuing value in toxin research. This is particularly important as many snake species worldwide are declining due to habitat destruction or modification. For some venoms (such as N. scutatus from Babel Island, Flinders Island, King Island and St. Francis Island) these were the first analyses ever conducted and these vintage samples may represent the only venom ever collected from these unique island forms of tiger snakes. Such vintage venoms may therefore represent the last remaining stocks of some local populations and thus are precious resources. These venoms also have significant historical value as
Bastos, Viviane A.; Gomes-Neto, Francisco; Perales, Jonas; Neves-Ferreira, Ana Gisele C.; Valente, Richard H.
The research on natural snake venom metalloendopeptidase inhibitors (SVMPIs) began in the 18th century with the pioneering work of Fontana on the resistance that vipers exhibited to their own venom. During the past 40 years, SVMPIs have been isolated mainly from the sera of resistant animals, and characterized to different extents. They are acidic oligomeric glycoproteins that remain biologically active over a wide range of pH and temperature values. Based on primary structure determination, mammalian plasmatic SVMPIs are classified as members of the immunoglobulin (Ig) supergene protein family, while the one isolated from muscle belongs to the ficolin/opsonin P35 family. On the other hand, SVMPIs from snake plasma have been placed in the cystatin superfamily. These natural antitoxins constitute the first line of defense against snake venoms, inhibiting the catalytic activities of snake venom metalloendopeptidases through the establishment of high-affinity, non-covalent interactions. This review presents a historical account of the field of natural resistance, summarizing its main discoveries and current challenges, which are mostly related to the limitations that preclude three-dimensional structural determinations of these inhibitors using “gold-standard” methods; perspectives on how to circumvent such limitations are presented. Potential applications of these SVMPIs in medicine are also highlighted. PMID:27571103
It is generally accepted that the biological activities of snake venom dried in vacuum at room temperature remain unaltered (Christensen 1955). The possibility of an alteration in biochemical properties due to the method of drying has been demonstrated by Bjork &. Boman (1959), but this would not necessarily influence the ...
Gutiérrez, José María
As a tribute to Revista de Biología Tropical in its 50th anniversary, this review describes some of the main research efforts carried out in the study of the chemical composition and the mechanism of action of toxins present in the venoms of snakes distributed in Latin America. Venom proteins involved in neurotoxicity, coagulopathies, hemorrhage and muscle necrosis are discussed, together with a description of the inflammatory reactions elicited by these venoms and toxins. In addition, the search for inhibitory substances present in plants and animals that may be utilized in the neutralization of venoms is analyzed. Some of the clinical studies performed on snakebite envenomations in Latin America are also reviewed, together with the development of technologies aimed at improving the quality of antivenoms produced in the region. Toxinology has become a fruitful and stimulating research field in Latin America which has contributed to a better understanding of snake venoms as well as to an improved management of snake bitten patients.
Poh Kuan Leong
Full Text Available BACKGROUND: Snake envenomation is a serious public health threat in the rural areas of Asian and African countries. To date, the only proven treatment for snake envenomation is antivenom therapy. Cross-neutralization of heterologous venoms by antivenom raised against venoms of closely related species has been reported. The present study examined the cross neutralizing potential of a newly developed polyvalent antivenom, termed Neuro Polyvalent Snake Antivenom (NPAV. NPAV was produced by immunization against 4 Thai elapid venoms. PRINCIPAL FINDINGS: In vitro neutralization study using mice showed that NPAV was able to neutralize effectively the lethality of venoms of most common Asiatic cobras (Naja spp., Ophiophagus hannah and kraits (Bungarus spp. from Southeast Asia, but only moderately to weakly effective against venoms of Naja from India subcontinent and Africa. Studies with several venoms showed that the in vivo neutralization potency of the NPAV was comparable to the in vitro neutralization potency. NPAV could also fully protect against N. sputatrix venom-induced cardio-respiratory depressant and neuromuscular blocking effects in anesthetized rats, demonstrating that the NPAV could neutralize most of the major lethal toxins in the Naja venom. CONCLUSIONS/SIGNIFICANCE: The newly developed polyvalent antivenom NPAV may find potential application in the treatment of elapid bites in Southeast Asia, especially Malaysia, a neighboring nation of Thailand. Nevertheless, the applicability of NPAV in the treatment of cobra and krait envenomations in Southeast Asian victims needs to be confirmed by clinical trials. The cross-neutralization results may contribute to the design of broad-spectrum polyvalent antivenom.
Leong, Poh Kuan; Sim, Si Mui; Fung, Shin Yee; Sumana, Khomvilai; Sitprija, Visith; Tan, Nget Hong
Background Snake envenomation is a serious public health threat in the rural areas of Asian and African countries. To date, the only proven treatment for snake envenomation is antivenom therapy. Cross-neutralization of heterologous venoms by antivenom raised against venoms of closely related species has been reported. The present study examined the cross neutralizing potential of a newly developed polyvalent antivenom, termed Neuro Polyvalent Snake Antivenom (NPAV). NPAV was produced by immunization against 4 Thai elapid venoms. Principal Findings In vitro neutralization study using mice showed that NPAV was able to neutralize effectively the lethality of venoms of most common Asiatic cobras (Naja spp.), Ophiophagus hannah and kraits (Bungarus spp.) from Southeast Asia, but only moderately to weakly effective against venoms of Naja from India subcontinent and Africa. Studies with several venoms showed that the in vivo neutralization potency of the NPAV was comparable to the in vitro neutralization potency. NPAV could also fully protect against N. sputatrix venom-induced cardio-respiratory depressant and neuromuscular blocking effects in anesthetized rats, demonstrating that the NPAV could neutralize most of the major lethal toxins in the Naja venom. Conclusions/Significance The newly developed polyvalent antivenom NPAV may find potential application in the treatment of elapid bites in Southeast Asia, especially Malaysia, a neighboring nation of Thailand. Nevertheless, the applicability of NPAV in the treatment of cobra and krait envenomations in Southeast Asian victims needs to be confirmed by clinical trials. The cross-neutralization results may contribute to the design of broad-spectrum polyvalent antivenom. PMID:22679522
Neurological manifestations in speech after snake bite: A rare case. D Vir, D Gupta, M Modi, N Panda. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/pamj.v4i1.53597 · AJOL African Journals Online. HOW TO ...
Takotsubo cardiomyopathy occurs in patients with severe emotional or physiologic stress. The prognosis is usually favorable, and the left ventricular wall motion dyskinesis normalizes within days to weeks. In this paper we report a case of snake bite complicated by takotsubo cardiomyopathy. We advise physicians to ...
Background: The aim of the study was to determine the knowledge of general practitioners in the rural areas of the Free State and Northern Cape regarding snake bites and their treatment. Methods: Telephonic interviews using structured questionnaires were conducted with a random sample of 50 general practitioners from ...
Jackson, Timothy N. W.; Sunagar, Kartik; Undheim, Eivind A. B.; Koludarov, Ivan; Chan, Angelo H. C.; Sanders, Kate; Ali, Syed A.; Hendrikx, Iwan; Dunstan, Nathan; Fry, Bryan G.
Despite the unparalleled diversity of venomous snakes in Australia, research has concentrated on a handful of medically significant species and even of these very few toxins have been fully sequenced. In this study, venom gland transcriptomes were sequenced from eleven species of small Australian elapid snakes, from eleven genera, spanning a broad phylogenetic range. The particularly large number of sequences obtained for three-finger toxin (3FTx) peptides allowed for robust reconstructions of their dynamic molecular evolutionary histories. We demonstrated that each species preferentially favoured different types of α-neurotoxic 3FTx, probably as a result of differing feeding ecologies. The three forms of α-neurotoxin [Type I (also known as (aka): short-chain), Type II (aka: long-chain) and Type III] not only adopted differential rates of evolution, but have also conserved a diversity of residues, presumably to potentiate prey-specific toxicity. Despite these differences, the different α-neurotoxin types were shown to accumulate mutations in similar regions of the protein, largely in the loops and structurally unimportant regions, highlighting the significant role of focal mutagenesis. We theorize that this phenomenon not only affects toxin potency or specificity, but also generates necessary variation for preventing/delaying prey animals from acquiring venom-resistance. This study also recovered the first full-length sequences for multimeric phospholipase A2 (PLA2) ‘taipoxin/paradoxin’ subunits from non-Oxyuranus species, confirming the early recruitment of this extremely potent neurotoxin complex to the venom arsenal of Australian elapid snakes. We also recovered the first natriuretic peptides from an elapid that lack the derived C-terminal tail and resemble the plesiotypic form (ancestral character state) found in viper venoms. This provides supporting evidence for a single early recruitment of natriuretic peptides into snake venoms. Novel forms of kunitz
Timothy N. W. Jackson
Full Text Available Despite the unparalleled diversity of venomous snakes in Australia, research has concentrated on a handful of medically significant species and even of these very few toxins have been fully sequenced. In this study, venom gland transcriptomes were sequenced from eleven species of small Australian elapid snakes, from eleven genera, spanning a broad phylogenetic range. The particularly large number of sequences obtained for three-finger toxin (3FTx peptides allowed for robust reconstructions of their dynamic molecular evolutionary histories. We demonstrated that each species preferentially favoured different types of α-neurotoxic 3FTx, probably as a result of differing feeding ecologies. The three forms of α-neurotoxin [Type I (also known as (aka: short-chain, Type II (aka: long-chain and Type III] not only adopted differential rates of evolution, but have also conserved a diversity of residues, presumably to potentiate prey-specific toxicity. Despite these differences, the different α-neurotoxin types were shown to accumulate mutations in similar regions of the protein, largely in the loops and structurally unimportant regions, highlighting the significant role of focal mutagenesis. We theorize that this phenomenon not only affects toxin potency or specificity, but also generates necessary variation for preventing/delaying prey animals from acquiring venom-resistance. This study also recovered the first full-length sequences for multimeric phospholipase A2 (PLA2 ‘taipoxin/paradoxin’ subunits from non-Oxyuranus species, confirming the early recruitment of this extremely potent neurotoxin complex to the venom arsenal of Australian elapid snakes. We also recovered the first natriuretic peptides from an elapid that lack the derived C-terminal tail and resemble the plesiotypic form (ancestral character state found in viper venoms. This provides supporting evidence for a single early recruitment of natriuretic peptides into snake venoms. Novel
Gao, Jian-Fang; Wang, Jin; Qu, Yan-Fu; Ma, Xiao-Mei; Ji, Xiang
We studied the immunoreactivity between venoms and commercial antiserums in four Chinese venomous snakes, Bungarus multicinctus, Naja atra, Deinagkistrodon acutus and Gloydius brevicaudus. Venoms from the four snakes shared common antigenic components, and most venom components expressed antigenicity in the immunological reaction between venoms and antiserums. Antiserums cross-reacted with heterologous venoms. Homologous venom and antiserum expressed the highest reaction activity in all cross-reactions. Species-specific antibodies (SSAbs) were obtained from four antiserums by immunoaffinity chromatography: the whole antiserum against each species was gradually passed through a medium system coated with heterologous venoms, and the cross-reacting components in antiserum were immunoabsorbed by the common antigens in heterologous venoms; the unbound components (i.e., SSAbs) were collected, and passed through Hitrap G protein column and concentrated. The SSAbs were found to have high specificity by western blot and enzyme-linked immunosorbent assay (ELISA). A 6-well ELISA strip coated with SSAbs was used to assign a venom sample and blood and urine samples from the envenomed rats to a given snake species. Our detections could differentiate positive and negative samples, and identify venoms of a snake species in about 35 min. The ELISA strips developed in this study are clinically useful in rapid and reliable identification of venoms from the above four snake species. Copyright © 2012 Elsevier B.V. All rights reserved.
Full Text Available BACKGROUND AND AIMS: Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL: Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of symptoms, neurological signs, and time taken for recovery. RESULTS: The offending snake was Russell′s viper in 27(48.2%, common and Sri Lankan krait in 19(33.9%, cobra in 3(5.4%, and unidentified in 7(12.5%. Ptosis was the commonest neurological manifestation seen in 48(85.7% followed by ophthalmoplegia (75%, limb weakness (26.8%, respiratory failure (17.9%, palatal weakness (10.7%, neck muscle weakness (7.1%, and delayed sensory neuropathy (1.8%. Neurological symptoms were experienced usually within 6 hours after the bite. Following administration of antivenom, the signs of recovery became evident within a few hours to several days. The duration for complete recovery ranged from four hours to two weeks. CONCLUSIONS: Complete recovery of neuromuscular weakness was observed in all patients except for one who died with intracerebral haemorrhage shortly after admission.
Portes-Junior, José A; Yamanouye, Norma; Carneiro, Sylvia M; Knittel, Paloma S; Sant'Anna, Sávio S; Nogueira, Fabio C S; Junqueira, Magno; Magalhães, Geraldo S; Domont, Gilberto B; Moura-da-Silva, Ana M
Snake venom metalloproteinases (SVMPs) are zinc-dependent enzymes responsible for most symptoms of human envenoming. Like matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase (ADAM) proteins, SVMPs are synthesized as zymogens, and enzyme activation is regulated by hydrolysis of their prodomain, but the processing of SVMPs is still unclear. In this study, we attempted to identify the presence of prodomain in different compartments of snake venom glands as zymogens or in the free form to elucidate some mechanism involved in SVMP activation. Using antibodies obtained by immunization with a recombinant prodomain, bands of zymogen molecular mass and prodomain peptides were detected mostly in gland extracts all along the venom production cycle and in the venom collected from the lumen at the peak of venom production. Prodomain was detected in secretory cells mostly in the secretory vesicles near the Golgi. We hypothesize that the processing of SVMPs starts within secretory vesicles and continues in the lumen of the venom gland just after enzyme secretion and involves different steps compared to ADAMs and MMPs but can be used as a model for studying the relevance of peptides resulting from prodomain processing and degradation for controlling the activity of metalloproteinases.
Shea, G M
The identification of dangerous Australian snakes is important in instituting therapy for envenomation. Despite the availability of a number of identification guides with varying degrees of generality, identification can be problematic for several reasons. These include a diversity of common names, many of which are inappropriate or regionally applied to different species, identification keys that focus on variable features, intraspecific variation and interspecific convergence in colouration, and recent changes in scientific nomenclature of species and genera. Geographic distribution of the dangerously venomous species can be a useful aid to identification, by limiting the range of options in a region. However, delineation of the limits of distribution relies on fine scale mapping beyond the resolution of most identification guides. This article provides a summary of the geographic limits of the dangerously venomous Australian snakes, with particular emphasis on major population centres, and clarifies some problems in identification, particularly among brown-coloured snakes.
This correspondence argues that the dangerousness of a venomous snake species is not solely determined by the venom characteristics or the lethality of the snake, and recognizes that medical importance comprises a key variable as well. The medical importance of a snake is determined by several factors - including frequency of medical attention after a bite, local or systemic envenomation provoked by the bite, fatal bites, long term consequences, availability of antivenom therapy as well as the size of the population at risk - that may vary from one region to another.
Cícera Maria Gomes
Full Text Available Background Snakes belonging to the Bothrops genus are vastly distributed in Central and South America and are responsible for most cases of reported snake bites in Latin America. The clinical manifestations of the envenomation caused by this genus are due to three major activities—proteolytic, hemorrhagic and coagulant—mediated by metalloproteinases, serine proteinases, phospholipases A2 and other toxic compounds present in snake venom. Interestingly, it was observed that snakes are resistant to the toxic effects of its own and other snake’s venoms. This natural immunity may occur due the absence of toxin target or the presence of molecules in the snake plasma able to neutralize such toxins. Methods In order to identify anti-venom molecules, we construct a cDNA library from the liver of B. jararaca snakes. Moreover, we analyzed the expression profile of four molecules—the already known anti-hemorrhagic factor Bj46a, one gamma-phospholipase A2 inhibitor, one inter-alpha inhibitor and one C1 plasma protease inhibitor—in the liver of juvenile and adult snakes by qPCR. Results The results revealed a 30-fold increase of gamma-phospholipase A2 inhibitor and a minor increase of the inter-alpha inhibitor (5-fold and of the C1 inhibitor (3-fold in adults. However, the Bj46a factor seems to be equally transcribed in adults and juveniles. Discussion The results suggest the up-regulation of different inhibitors observed in the adult snakes might be a physiological adaptation to the recurrent contact with their own and even other snake’s venoms throughout its lifespan. This is the first comparative analysis of ontogenetic variation of expression profiles of plasmatic proteins with potential anti-venom activities of the venomous snake B. jararaca. Furthermore, the present data contributes to the understanding of the natural resistance described in these snakes.
Ibrahim, Nihal M; El-Kady, Ebtsam M; Katamesh, Rania A; El-Borei, Ibrahim H; Wahby, Ahmed F
The avidity to the corresponding antigens is often higher than to the cross-reactive antigens. This was demonstrated with the highly cross-reactive elapid Egyptian snake venoms Naja haje (Nh), Naja nigricollis (Nn) and Walterinnesia aegyptia (Wa), and used for the differentiation among the three species in a simple ELISA-based assay. A three-step immuno-affinity protocol was followed and the titer and avidity of the different antibody (Ab) preparations were assessed and evaluated. The advantages offered by the avidity power of the venom specific antibodies (VS-Abs) obtained after one step purification, outweigh the specificity of the species-specific antibodies (SS-Abs) obtained after further purification. The efficiency of the VS-Abs as special immunodiagnostics was validated using 16 venom samples collected from individual snakes of different size and age at different time intervals. The avidities of the VS-Abs to the homologous venoms were 2.53 ± 0.4, 2.66 ± 0.31 and 2.8 ± 0.06 for Nh, Nn and Wa venoms respectively; whereas the avidity of the same Abs to the heterologous venoms could hardly exceed 1. Venom concentrations in the range between 10-1250 ng/well were detected with almost the same efficiency, an extra advantage that could be added to the assay to assure equal sensitivity allover the mentioned venom concentration range. Copyright © 2012 Elsevier Ltd. All rights reserved.
Skejić, Jure; Hodgson, Wayne C.
This study looked at how toxic proteins in venoms of adult Australian eastern Brown snakes Pseudonaja textilis from South Australian and Queensland populations interact with physiological functions of the lab SD rat Rattus norvegicus. Circulatory collapse and incoagulable blood occurred instantly after injection of venom under the dorsal skin of anaesthetised and mechanically ventilated rats in an imitation of a P. textilis bite. Intravenous injection of purified P. textilis (Mackay, QLD) venom prothrombin activator proteins caused instant failure of circulation, testifying of high toxicity of these proteins and suggesting their role in rapid incapacitation of rodent prey. The hypothesis is further supported by circulatory collapse occurring instantly despite artificial respiration in envenomed rats and the finding of extremely high venom procoagulant potency in rat plasma. LC-MS and physiology assays revealed divergent venom composition and biological activity of South Australian (Barossa locality) and Queensland (Mackay locality) populations, which may be driven by selection for different prey. The Queensland venom of P. textilis was found to be more procoagulant and to exhibit predominately presynaptic neurotoxicity, while the South Australian venom contained diverse postsynaptic type II and III α-neurotoxins in addition to the presynaptic neurotoxins and caused significantly faster onset of neuromuscular blockade in the rat phrenic nerve-diaphragm preparation. LC-MS analysis found evidence of multiple coagulation factor X-like proteins in P. textilis venoms, including a match to P. textilis coagulation factor X isoform 2, previously known to be expressed only in the liver. PMID:23691135
Full Text Available This study looked at how toxic proteins in venoms of adult Australian eastern Brown snakes Pseudonaja textilis from South Australian and Queensland populations interact with physiological functions of the lab SD rat Rattus norvegicus. Circulatory collapse and incoagulable blood occurred instantly after injection of venom under the dorsal skin of anaesthetised and mechanically ventilated rats in an imitation of a P. textilis bite. Intravenous injection of purified P. textilis (Mackay, QLD venom prothrombin activator proteins caused instant failure of circulation, testifying of high toxicity of these proteins and suggesting their role in rapid incapacitation of rodent prey. The hypothesis is further supported by circulatory collapse occurring instantly despite artificial respiration in envenomed rats and the finding of extremely high venom procoagulant potency in rat plasma. LC-MS and physiology assays revealed divergent venom composition and biological activity of South Australian (Barossa locality and Queensland (Mackay locality populations, which may be driven by selection for different prey. The Queensland venom of P. textilis was found to be more procoagulant and to exhibit predominately presynaptic neurotoxicity, while the South Australian venom contained diverse postsynaptic type II and III α-neurotoxins in addition to the presynaptic neurotoxins and caused significantly faster onset of neuromuscular blockade in the rat phrenic nerve-diaphragm preparation. LC-MS analysis found evidence of multiple coagulation factor X-like proteins in P. textilis venoms, including a match to P. textilis coagulation factor X isoform 2, previously known to be expressed only in the liver.
Faiz, Abul; Ghose, Aniruddha; Ahsan, Farid; Rahman, Ridwanur; Amin, Robed; Hassan, Mahtab Uddin; Chowdhury, A Wahed; Kuch, Ulrich; Rocha, Thalita; Harris, John B; Theakston, R David G; Warrell, David A
Prospective studies of snake bite patients in Chittagong, Bangladesh, included five cases of bites by greater black kraits (Bungarus niger), proven by examination of the snakes that had been responsible. This species was previously known only from India, Nepal, Bhutan and Burma. The index case presented with descending flaccid paralysis typical of neurotoxic envenoming by all Bungarus species, but later developed generalized rhabdomyolysis (peak serum creatine kinase concentration 29,960 units/l) with myoglobinuria and acute renal failure from which he succumbed. Among the other four patients, one died of respiratory paralysis in a peripheral hospital and three recovered after developing paralysis, requiring mechanical ventilation in one patient. One patient suffered severe generalized myalgia and odynophagia associated with a modest increase in serum creatine kinase concentration. These are the first cases of Bungarus niger envenoming to be reported from any country. Generalized rhabdomyolysis has not been previously recognized as a feature of envenoming by any terrestrial Asian elapid snake, but a review of the literature suggests that venoms of some populations of Bungarus candidus and Bungarus multicinctus in Thailand and Vietnam may also have this effect in human victims. To investigate this unexpected property of Bungarus niger venom, venom from the snake responsible for one of the human cases of neuro-myotoxic envenoming was injected into one hind limb of rats and saline into the other under buprenorphine analgesia. All animals developed paralysis of the venom-injected limb within two hours. Twenty-four hours later, the soleus muscles were compared histopathologically and cytochemically. Results indicated a predominantly pre-synaptic action (β-bungarotoxins) of Bungarus niger venom at neuromuscular junctions, causing loss of synaptophysin and the degeneration of the terminal components of the motor innervation of rat skeletal muscle. There was oedema and
The ophidiological survey made in Zaire revealed the presence of 152 species of snakes included in 60 genera and in 8 families. The family Colubridae contains the largest number of genera (45) and species (97). Their geographical distribution shows that the eastern part of Kivu region contains a wild variety of species (90 species). The density of Zairean snakes has not yet been known. But in some localities like Kamanyola in the Kivu province, the density is as high as 80 individuals per squ...
Weinstein, Scott A
The ancient perceptions of "venomous" and "poisonous snakes", as well as the Indo-European (IE) etymological origins of the term "venom" specifically associated with snakes are considered. Although several ancient cultures perceived snakes as symbols of fecundity and renewal, concurrent beliefs also associated venomous snakes with undesirable human characteristics or as portending non-propitious events. The respective IE roots of the terms "venom" and "poison", "wen" and "poi" refer to desire or the act of ingesting liquids. The origin of the term, "venom", is associated with polytheistic cults that emphasized attainment of desires sometimes assisted by "love potions", a term later interpolated with the word, "poison". Specific interpretation of the term, venom, has varied since its first probable use in the mid-Thirteenth Century. The definition of snake venom has long been contended, and interpretations have often reflected emphasis on the pharmacological or experimental toxicity of medically relevant snake venoms with less regard for the basic biological bases of these venoms, as well as those from snakes with no known medical significance. Several definitions of "snake venom" and their defining criteria are reviewed, and critical consideration is given to traditional criteria that might facilitate the future establishment of a biologically accurate definition. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
Hill, R E; Mackessy, S P
R.E. Hill and S.P. Mackessy. Characterization of venom (Duvernoy's secretion) from twelve species of colubrid snakes and partial sequence of four venom proteins. Toxicon XX, xx-yy, 2000. - Venomous colubrids, which include more than 700 snake species worldwide, represent a vast potential source of novel biological compounds. The present study characterized venom (Duvernoy's gland secretion) collected from twelve species of opisthoglyphous (rear-fanged) colubrid snakes, an extremely diverse assemblage of non-venomous to highly venomous snakes. Most venoms displayed proteolytic activity (casein), though activity levels varied considerably. Low phosphodiesterase activity was detected in several venoms (Amphiesma stolata, Diadophis punctatus, Heterodon nasicus kennerlyi, H. n. nasicus and Thamnophis elegans vagrans), and acetylcholinesterase was found in Boiga irregularis saliva and venom, but no venoms displayed hyaluronidase, thrombin-like or kallikrein-like activities. High phospholipase A(2) (PLA(2)) activity was found in Trimorphodon biscutatus lambda venom, and moderate levels were detected in Boiga dendrophila and D. p. regalis venoms as well as B. dendrophila and H. n. nasicus salivas. Non-reducing SDS-PAGE revealed 7-20 protein bands (3.5 to over 200 kD, depending on species) for all venoms analyzed, and electrophoretic profiles of venoms were typically quite distinct from saliva profiles. Components from A. stolata, Hydrodynastes gigas, Tantilla nigriceps and T. e. vagrans venoms showed protease activity when run on gelatin zymogram gels. N-terminal protein sequences for three 26 kD venom components of three species (H. gigas, H. torquata, T. biscutatus) and one 3.5 kD component (T. nigriceps) were also obtained, and the 3.5 kD peptide showed apparent sequence homology with human vascular endothelial growth factor; these data represent the first sequences of colubrid venom components. Protease, phosphodiesterase and PLA(2) activities are also common to elapid
Narasimham; Srinivasa Rao
BACKGROUND AND OBJECTIVES: Snake bites are of major public health importance in many communities as causes of haemorrhage, other morbidity and mortality. 1 Of the 3000 species of snakes, about 500 belong to the 3 families of venomous snakes, Atr actaspididae, Elapidae and Viperidae. Estimated 15000 – 20000 people die each year from snake bite in India. 2 In tropical countries snake bite is occupational disease of farmers, plantation workers and hunters. In ...
Aird, Steven D; Aggarwal, Shikha; Villar-Briones, Alejandro; Tin, Mandy Man-Ying; Terada, Kouki; Mikheyev, Alexander S
While many studies have shown that extracellular proteins evolve rapidly, how selection acts on them remains poorly understood. We used snake venoms to understand the interaction between ecology, expression level, and evolutionary rate in secreted protein systems. Venomous snakes employ well-integrated systems of proteins and organic constituents to immobilize prey. Venoms are generally optimized to subdue preferred prey more effectively than non-prey, and many venom protein families manifest positive selection and rapid gene family diversification. Although previous studies have illuminated how individual venom protein families evolve, how selection acts on venoms as integrated systems, is unknown. Using next-generation transcriptome sequencing and mass spectrometry, we examined microevolution in two pitvipers, allopatrically separated for at least 1.6 million years, and their hybrids. Transcriptomes of parental species had generally similar compositions in regard to protein families, but for a given protein family, the homologs present and concentrations thereof sometimes differed dramatically. For instance, a phospholipase A2 transcript comprising 73.4 % of the Protobothrops elegans transcriptome, was barely present in the P. flavoviridis transcriptome (venoms. Protein evolutionary rates were positively correlated with transcriptomic and proteomic abundances, and the most abundant proteins showed positive selection. This pattern holds with the addition of four other published crotaline transcriptomes, from two more genera, and also for the recently published king cobra genome, suggesting that rapid evolution of abundant proteins may be generally true for snake venoms. Looking more broadly at Protobothrops, we show that rapid evolution of the most abundant components is due to positive selection, suggesting an interplay between abundance and adaptation. Given log-scale differences in toxin abundance, which are likely correlated with biosynthetic costs, we
Full Text Available INTRODUCTION Snakebite is an important cause of mortality and morbidity in India. India has the highest number of deaths due to snake bite1 Neurotoxicity due to snakebite is well-known with varied presentation.2 Common cases of snakebites are of saw-scaled viper (Echis carinatus, Russell’s viper (a viperidae, krait (Bungarus caeruleus, common cobra (Naja naja king cobra (Ophiophagus hannah.3
Justin; Manivannan,; Ramu
INTRODUCTION Snakebite is an important cause of mortality and morbidity in India. India has the highest number of deaths due to snake bite1 Neurotoxicity due to snakebite is well-known with varied presentation.2 Common cases of snakebites are of saw-scaled viper (Echis carinatus), Russell’s viper (a viperidae), krait (Bungarus caeruleus), common cobra (Naja naja) king cobra (Ophiophagus hannah).3
Rodríguez-Acosta, Alexis; Sánchez, Elda E; Márquez, Adriana; Carvajal, Zoila; Salazar, Ana M; Girón, María E; Estrella, Amalid; Gil, Amparo; Guerrero, Belsy
In Venezuela, Bothrops snakes are responsible for more than 80% of all recorded snakebites. This study focuses on the biological and hemostatic characteristics of Bothrops isabelae venom along with its comparative characteristics with two other closely related Bothrops venoms, Bothrops atrox and Bothrops colombiensis. Electrophoretic profiles of crude B. isabelae venom showed protein bands between 14 and 100 kDa with the majority in the range of 14-31 kDa. The molecular exclusion chromatographic profile of this venom contains five fractions (F1-F5). Amidolytic activity evaluation evidenced strong thrombin-like followed by kallikrein-like activities in crude venom and in fractions F1 and F2. The fibrinogenolytic activity of B. isabelae venom at a ratio of 100:1 (fibrinogen/venom) induced a degradation of A alpha and B beta chains at 15 min and 2 h, respectively. At a ratio of 100:10, a total degradation of A alpha and B beta chains at 5 min and of gamma chains at 24 h was apparent. This current study evidences one of rarely reported for Bothrops venoms, which resembles the physiologic effect of plasmin. B. isabelae venom as well as F2 and F3 fractions, contain fibrinolytic activity on fibrin plate of 36, 23.5 and 9.45 mm(2)/microg, respectively using 25 microg of protein. Crude venom and F1 fraction showed gelatinolytic activity. Comparative analysis amongst Venezuelan bothropoid venoms, evidenced that the LD(50) of B. isabelae (5.9 mg/kg) was similar to B. atrox-Puerto Ayacucho 1 (6.1 mg/kg) and B. colombiensis-Caucagua (5.8 mg/kg). B. isabelae venom showed minor hemorrhagic activity, whereas B. atrox-Parguasa (Bolivar state) was the most hemorrhagic. In this study, a relative high thrombin-like activity was observed in B. colombiensis venoms (502-568 mUA/min/mg), and a relative high factor Xa-like activity was found in B. atrox venoms (126-294 mUA/min/mg). Fibrinolytic activity evaluated with 10 microg protein, showed that B. isabelae venom contained higher
Afshin Mohammad Alizadeh
Full Text Available The aim of the current study is to compare three different methods of treatment of snake bite to determine the most efficient one. To unify the protocol of snake bite treatment in our center, we retrospectively reviewed files of the snake-bitten patients who had been referred to us between 2010 and 2014. They were contacted for follow-up using phone calls. Demographic and on-arrival characteristics, protocol used for treatment (WHO/Haddad/GF, and outcome/complications were evaluated. Patients were entered into one of the protocol groups and compared. Of a total of 63 patients, 56 (89% were males. Five, 19, and 28 patients were managed by Haddad, WHO, or GF protocols, respectively. Eleven patients had fallen into both GF and WHO protocols and were excluded. Serum sickness was significantly more common when WHO protocol was used while 100% of the compartment syndromes and 71% of deformities had been reported after GF protocol. The most important complications were considered to be deformity, compartment syndrome, and amputation and were more frequent after the use of WHO and GF protocols (23.1% versus 76.9%; none in Haddad; P = NS. Haddad protocol seems to be the best for treatment of snake-bitten patients in our region. However, this cannot be strictly concluded because of the limited sample size and nonsignificant P values.
Tan, Choo Hock; Tan, Kae Yi; Tan, Nget Hong
Recent advances in proteomics enable deep profiling of the compositional details of snake venoms for improved understanding on envenomation pathophysiology and immunological neutralization. In this study, the venom of Australian tiger snake (Notechis scutatus) was trypsin-digested in solution and subjected to nano-ESI-LCMS/MS. Applying a relative quantitative proteomic approach, the findings revealed a proteome comprising 42 toxin subtypes clustered into 12 protein families. Phospholipases A2 constitute the most abundant toxins (74.5% of total venom proteins) followed by Kunitz serine protease inhibitors (6.9%), snake venom serine proteases (5.9%), alpha-neurotoxins (5.6%) and several toxins of lower abundance. The proteome correlates with N. scutatus envenoming effects including pre-synaptic and post-synaptic neurotoxicity and consumptive coagulopathy. The venom is highly lethal in mice (intravenous median lethal dose=0.09μg/g). BioCSL Sea Snake Antivenom, raised against the venoms of beaked sea snake (Hydrophis schistosus) and N. scutatus (added for enhanced immunogenicity), neutralized the lethal effect of N. scutatus venom (potency=2.95mg/ml) much more effectively than the targeted H.schistosus venom (potency=0.48mg/ml). The combined venom immunogen may have improved the neutralization against phospholipases A2 which are abundant in both venoms, but not short-neurotoxins which are predominant only in H. schistosus venom. A shotgun proteomic approach adopted in this study revealed the compositional details of the venom of common tiger snake from Australia, Notechis scutatus. The proteomic findings provided additional information on the relative abundances of toxins and the detection of proteins of minor expression unreported previously. The potent lethal effect of the venom was neutralized by bioCSL Sea Snake Antivenom, an anticipated finding due to the fact that the Sea Snake Antivenom is actually bivalent in nature, being raised against a mix of venoms of the
Bhalla, Gaurav; Mhaskar, Dhanesh; Agarwal, Anubhav
Background: Snake bite is an important occupational and rural hazard because India has always been a land of Exotic snakes. In Maharashtra, common poisonous snakes are Cobra, Russell's Viper, Saw Scaled Viper, and Krait. It is a fact that inspite of heavy morbidity and mortality, very little attention is paid by the clinicians to this occupational hazard. Aims: To study the prevalence of poisonous and non-poisonous snake bites in part of Western Maharashtra with reference to age, sex, occupation, part of body bitten, time of bite and seasonal variation, and the types of poisonous snakes common in this locality and their clinical manifestations along with the systemic envenomation from various types of poisonous snakes and their effective management in reducing the mortality rate. Materials and Methods: This was a retrospective study conducted between May 2010 to May 2012 at a tertiary health care center in Maharashtra. Result: A total of 150 patients were studied in our hospital. Out of 150, 76 patients were of poisonous snake bite and 74 patients were of non-poisonous snake bite. Out of these 76 poisonous snake bites, 42 were viperine snake bites, 21 were neuroparalytic snake bites and 13 were locally toxic (LT) snake bites. Conclusion: Snake bite is a common life-threatening emergency in the study area. Delay in hospitalization is associated with poor prognosis and increased mortality rate due to consumptive coagulopathy, renal failure, and respiratory failure. Unusual complications like pulmonary edema, intracerebral hemorrhage, Disseminated intravascular coagulation (DIC) were observed in present study. PMID:25253932
Sánchez, Elda E; Lopez-Johnston, Juan C; Rodríguez-Acosta, Alexis; Pérez, John C
Elapid snakes throughout the world are considered very lethal, containing neurotoxic venoms that affect the nervous system. When humans are envenomated it is considered a serious medical emergency, and antivenom is the main form of treatment considered, in spite of the fact that some patients may only survive under intensive therapy treatment such as respiratory support. Coral snakes are part of the family Elapidae and envenomations by these snakes are very low (coral snakes of medical importance that belong to the Micrurus genera: Micrurus fulvius fulvius (Eastern coral snake) and Micrurus tener tener (Texas coral snake). In 2006, Wyeth pharmaceutical notified customers that the production of the North American coral snake antivenin (NACSA) in the US was discontinued and adequate supplies were available to meet historical needs through the end of October 2008; and therefore, it is of utmost important to consider other antivenoms as alternatives for the treatment of coral snake envenoming. One logical alternative is the coral snake antivenom, Coralmyn, produced by the Mexican company, Bioclon. In order to compare neutralization between NACSA and Coralmyn antivenoms with the North American coral snake venoms, the venom lethal doses (LD(50)) and antivenom effective doses (ED(50)) were determined in 18-20 g, female, BALB/c mice. Additionally, venom comparisons were determined through a non-reduced SDS-PAGE for M.f.fulvius, M.t.tener and the Mexican coral snake venom, Micrurus nigrocinctus nigrocinctus. Coralmyn antivenom was able to effectively neutralize three LD(50) doses of all venom from both M.t.tener and M.f.fulvius, while Wyeth antivenom only neutralized M.f.fulvius venom and was not effective in neutralizing three LD(50) doses of M.t.tener venom. Coralmyn is effective in the neutralization of both clinically important coral snake venoms in the US.
Snake venoms contain compound(s) that enhanced cyclic AMP content in human mononuclear leukocytes maximally after 5 min of incubation at 37 degrees C. The effect was time- and dose-dependent. The half-maximal stimulation of cyclic AMP production by black cobra venom was found at 0.45 micrograms of venom/ml and the value of the Hill coefficient was 0.7. The black cobra venom enhanced the cyclic AMP content in the cells at 4, 22, and 37 degrees C. Similar increase in the cyclic AMP content by six snake venoms was found in human polymorphonuclear leukocytes. The most active venom was from puff adder (Bitis arietans). The data suggest that one of the effects of the snake venoms may be rapid enhancement of cyclic AMP level in the affected cells.
ethnopharmacology revealed several of these medicinal plants with potential to treat snake bite. This work was designed to document medicinal plants used by Fulani herdsmen in Taraba State, Nigeria, for the treatment of snake bites. Information provided will enable further study on the efficacy of the medicinal plants so ...
Objective: To assess the pattern of clinical presentation and management outcome of snake bite victims treated in a comprehensive health centre in a rural setting in North-Central zone of Nigeria where snake bite morbidity and mortality are known to be unacceptably high. Methods: All records of admission in the ...
Background: A lot of work had been done on the clinical profiles of patients with snake bites but none on female patients alone. In this medical audit, we undertook to study the clinical profiles of snake bites among female patients seen over a two year period at a federal Government designated treatment centre, Zamko.
Purpose: Although snake bites occur frequently in Benin City, the prevalence has not been documented. This study was therefore done to determine the prevalence, morbidity, mortality, and the orthodox treatment of victims. Methods: The study was retrospective and data on victims of snake bite covering a period of twenty ...
Jun 2, 2016 ... Method: The study was a descriptive cross-sectional review of 2006 - 2010 snake bite secondary data generated by the Western Regional Health Information Office in Ghana. Data was .... Estimate of the burden of Snake bites in Sub-Saharan Africa; A meta-analytic approach. Toxicon. 2011; 57(4): 586-99.
Sanz, Libia; Pla, Davinia; P?rez, Alicia; Rodr?guez, Yania; Zavaleta, Alfonso; Salas, Maria; Lomonte, Bruno; Calvete, Juan J.
The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs) constitute, both in number of isoforms (~30) and total abundance (93.6% of the venom proteome), the major protein family of the desert coral snake venom. Phospholipases A₂ (PLA₂s; seven isoforms, 4.1% of the venom proteome), 1-3 Kunitz-type proteins (1.6%)...
Heiner, Jason D; Bebarta, Vikhyat S; Varney, Shawn M; Bothwell, Jason D; Cronin, Aaron J
Annually, more than 100,000 US and international military and civilian personnel work in Afghanistan within terrain harboring venomous snakes. Current literature insufficiently supports Afghan antivenom treatment and stocking guidelines. We report the clinical course and treatments for snakebite victims presenting to US military hospitals in Afghanistan. All snakebite victims presenting to 3 US military emergency departments between July 2010 and August 2011 in northern and southern Afghanistan were examined via chart review. Case information included patient demographics, snake description, bite details and complications, laboratory results, antivenom use and adverse effects, procedures performed, and hospital course. Of 17 cases, median patient age was 20 years (interquartile range [IQR], 12-30), 16 were male, and 82% were Afghans. All bites were to an extremity, and median time to care was 2.8 hours (IQR, 2-5.8). On arrival, 8 had tachycardia and none had hypotension or hypoxia. A viper was implicated in 5 cases. Ten cases received at least 1 dose of polyvalent antivenom, most commonly for coagulopathy, without adverse effects. Six received additional antivenom, 6 had an international normalized ratio (INR) > 10, and none developed delayed coagulopathy. Three received blood transfusions. Hospital stay ranged from 1 to 4 days. None required vasopressors, fasciotomy, or other surgery, and none died. All had resolution of marked coagulopathies and improved swelling and pain on discharge. We report the largest series of snake envenomations treated by US physicians in Afghanistan. Antivenom was tolerated well with improvement of coagulopathy and symptoms. All patients survived with minimal advanced interventions other than blood transfusion. Published by Elsevier Inc.
Full Text Available Phospholipases type A2 (PLA2s are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2 are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, and integrins.
Zouari-Kessentini, Raoudha; Srairi-Abid, Najet; Bazaa, Amine; El Ayeb, Mohamed; Luis, Jose; Marrakchi, Naziha
Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins. PMID:23509718
Roy, Manoj Kumar; Dutta, Joydip; Chatterjee, Apratim; Sarkar, Anup; Roy, Koushik; Agarwal, Rakhesh; Lahiri, Durjoy; Biswas, Amrito; Mondal, Anupam; Maity, Pranab; Mukhopadhyay, Jotideb
Snake bites are very common in India, particularly in West Bengal. Snake bite can cause various hematological, neuromyopathical complications. It can be very fatal if not detected and treated early. Timely intervention can save the patient. We are reporting a case of hematotoxic Russell viper snake bite presented with subarachnoid hemorrhage. Patient was successfully treated with antivenom serum (AVS) along with other conservative management. Subarachnoid hemorrhage as an initial presentation in viper bite is very rare and we discuss the case with proper literature review.
Wisniewski, Michael S; Hill, Robert E; Havey, Joshua M; Bogdan, Gregory M; Dart, Richard C
Wyeth-Ayerst has discontinued production of Antivenin (Micrurus fulvius). Currently, there is no other approved coral snake antivenom available in the United States. This study was a randomized, placebo-controlled and blinded determination of the ability of a Mexican Micrurus (coral snake) antivenom and an Australian Notechis (tiger snake) antivenom to prevent lethality from a United States Micrurus fulvius fulvius venom in a mouse model. Venom dosing was based on an LD50 determined for this experiment. Our comparison groups included: (1) M. f. fulvius venom + Micrurus antivenom, (2) M. f. fulvius venom + Notechis antivenom, (3) M. f. fulvius venom + protein control, (4) 0.9% normal saline + protein control, (5) saline + Notechis antivenom, (6) saline + Micrurus antivenom. Venom dose was 5 times the determined LD50. The antivenom amounts were capable of neutralizing 10 times the venom injected (50 times the LD50). The LD50 of M. f. fulvius venom was determined to be 0.85 mg/kg. All mice in both antivenom test groups were protected from lethality for the entire 24-hour observation period. Six of the 7 mice in the venom test group died, with a survival time of 349 +/- 382 minutes (mean +/- s.d.) after the venom injection. All three groups of control mice survived the entire 24-hour observation period. Mexican Micrurus antivenom and Australian Notechis antivenom provide protection from lethality in mice envenomated with a United States M. f. filvius venom.
Rees, B.; Samama, J.P.; Thierry, J.C.; Gilibert, M.; Fischer, J.; Schweitz, H.; Lazdunski, M.; Moras, D.
Cardiotoxin V/sup II/4 from Naja mossambica crystallizes in space group P6/sub 1/ (a = b = 73.9 A; c = 59.0 A) with two molecules of toxin (molecular mass = 6715 Da) in the asymmetric unit. The structure was solved by using a combination of multiple isomorphous replacement and density modification methods. Model building and least-squares refinement led to an agreement factor of 27% for a data set to 3-A resolution prior to any inclusion of solvent molecules. The topology of the molecule is similar to that found in short and long snake neurotoxins, which block the nicotinic acetylcholine receptor. Major differences occur in the conformation of the central loop, resulting in a change in the concavity of the molecule. Hydrophobic residues are clustered in two distinct areas. The existence of stable dimeric entities in the crystalline state, with the formation of a six-stranded antiparallel ..beta.. sheet, may be functionally relevant.
Vonk, Freek J; Casewell, Nicholas R; Henkel, Christiaan V; Heimberg, Alysha M; Jansen, Hans J; McCleary, Ryan J R; Kerkkamp, Harald M E; Vos, Rutger A; Guerreiro, Isabel; Calvete, Juan J; Wüster, Wolfgang; Woods, Anthony E; Logan, Jessica M; Harrison, Robert A; Castoe, Todd A; de Koning, A P Jason; Pollock, David D; Yandell, Mark; Calderon, Diego; Renjifo, Camila; Currier, Rachel B; Salgado, David; Pla, Davinia; Sanz, Libia; Hyder, Asad S; Ribeiro, José M C; Arntzen, Jan W; van den Thillart, Guido E E J M; Boetzer, Marten; Pirovano, Walter; Dirks, Ron P; Spaink, Herman P; Duboule, Denis; McGlinn, Edwina; Kini, R Manjunatha; Richardson, Michael K
Snakes are limbless predators, and many species use venom to help overpower relatively large, agile prey. Snake venoms are complex protein mixtures encoded by several multilocus gene families that function synergistically to cause incapacitation. To examine venom evolution, we sequenced and interrogated the genome of a venomous snake, the king cobra (Ophiophagus hannah), and compared it, together with our unique transcriptome, microRNA, and proteome datasets from this species, with data from other vertebrates. In contrast to the platypus, the only other venomous vertebrate with a sequenced genome, we find that snake toxin genes evolve through several distinct co-option mechanisms and exhibit surprisingly variable levels of gene duplication and directional selection that correlate with their functional importance in prey capture. The enigmatic accessory venom gland shows a very different pattern of toxin gene expression from the main venom gland and seems to have recruited toxin-like lectin genes repeatedly for new nontoxic functions. In addition, tissue-specific microRNA analyses suggested the co-option of core genetic regulatory components of the venom secretory system from a pancreatic origin. Although the king cobra is limbless, we recovered coding sequences for all Hox genes involved in amniote limb development, with the exception of Hoxd12. Our results provide a unique view of the origin and evolution of snake venom and reveal multiple genome-level adaptive responses to natural selection in this complex biological weapon system. More generally, they provide insight into mechanisms of protein evolution under strong selection.
Snake bite leads to medical emergencies and sometimes death. It is clinically managed by administration of monovalent/polyvalent antisera and it exhibit early or late adverse reactions and sometimes these adverse effects lead to fatalities. Cassia hirsute has been used against snake bite by the traditional healers; however ...
Tan, Choo Hock; Fung, Shin Yee; Yap, Michelle Khai Khun; Leong, Poh Kuan; Liew, Jia Lee; Tan, Nget Hong
The venom proteome of the Malayan blue coral snake, Calliophis bivirgata flaviceps from west Malaysia was investigated by 1D-SDS-PAGE and shotgun-LCMS/MS. A total of 23 proteins belonging to 11 protein families were detected from the venom proteome. For the toxin proteins, the venom consists mainly of phospholipase A2 (41.1%), cytotoxin (22.6%), SVMPs (18.7%) and vespryns (14.6%). However, in contrast to the venoms of New World coral snakes and most elapids, there was no post-synaptic α-neurotoxin detected. The proteome also revealed a relatively high level of phosphodiesterase (1.3%), which may be associated with the reported high level of adenosine in the venom. Also detected were 5'-nucleotidase (0.3%), hyaluronidase (0.1%) and cysteine-type endopeptide inhibitor (0.6%). Enzymatic studies confirmed the presence of phospholipase A2, phosphodiesterase, 5'-nucleotidase and acetylcholinesterase activities but not l-amino acid oxidase activity. The venom exhibited moderate cytotoxic activity against CRL-2648 fibroblast cell lines (IC50=62.14±0.87 μg/mL) and myotoxicity in mice, presumably due to the action of its cytotoxin or its synergistic action with phospholipase A2. Interestingly, the venom lethality could be cross-neutralized by a neurotoxic bivalent antivenom from Taiwan. Together, the findings provide insights into the composition and functions of the venom of this exotic oriental elapid snake. While venoms of the New World coral snake have been extensively studied, literature pertaining to the Old World or Asiatic coral snake venoms remains lacking. This could be partly due to the inaccessibility to the venom of this rare species and infrequent cases of envenomation reported. This study identified and profiled the venom proteome of the Malayan blue coral snake (C. b. flaviceps) through SDS-PAGE and a high-resolution nano-LCMS/MS method, detailing the types and abundance of proteins found in the venom. The biological and toxic activities of the venom were
Ariaratnam, Christeine A; Sheriff, Mohamed H Rezvi; Arambepola, Carukshi; Theakston, R David G; Warrell, David A
Of 860 snakes brought to 10 hospitals in Sri Lanka with the patients they had bitten, 762 (89%) were venomous. Russell's vipers (Daboia russelii) and hump-nosed pit vipers (Hypnale hypnale) were the most numerous and H. hypnale was the most widely distributed. Fifty-one (6%) were misidentified by hospital staff, causing inappropriate antivenom treatment of 13 patients. Distinctive clinical syndromes were identified to aid species diagnosis in most cases of snake bite in Sri Lanka where the biting species is unknown. Diagnostic sensitivities and specificities of these syndromes for envenoming were 78% and 96% by Naja naja, 66% and 100% by Bungarus caeruleus, 14% and 100% by Daboia russelii, and 10% and 97% by Hypnale hypnale, respectively. Although only polyspecific antivenoms are used in Sri Lanka, species diagnosis remains important to anticipate life-threatening complications such as local necrosis, hemorrhage and renal and respiratory failure and to identify likely victims of envenoming by H. hypnale who will not benefit from existing antivenoms. The technique of hospital-based collection, labeling and preservation of dead snakes brought by bitten patients is recommended for rapid assessment of a country's medically-important herpetofauna.
Thaisa Francielle Souza Domingos
Full Text Available Snake venoms are composed of a complex mixture of active proteins and peptides which induce a wide range of toxic effects. Envenomation by Bothrops jararaca venom results in hemorrhage, edema, pain, tissue necrosis and hemolysis. In this work, the effect of a mixture of two secodolastane diterpenes (linearol/isolinearol, previously isolated from the Brazilian marine brown alga, Canistrocarpus cervicornis, was evaluated against some of the toxic effects induced by B. jararaca venom. The mixture of diterpenes was dissolved in dimethylsulfoxide and incubated with venom for 30 min at room temperature, and then several in vivo (hemorrhage, edema and lethality and in vitro (hemolysis, plasma clotting and proteolysis assays were performed. The diterpenes inhibited hemolysis, proteolysis and hemorrhage, but failed to inhibit clotting and edema induced by B. jararaca venom. Moreover, diterpenes partially protected mice from lethality caused by B. jararaca venom. The search for natural inhibitors of B. jararaca venom in C. cervicornis algae is a relevant subject, since seaweeds are a rich and powerful source of active molecules which are as yet but poorly explored. Our results suggest that these diterpenes have the potential to be used against Bothropic envenomation accidents or to improve traditional treatments for snake bites.
Cherlin Vladimir Alexandrovich
Full Text Available The article gives brief biographical information about a very talented herpetologist Alexander M. Zakharov, and describes the general results of his works on the structure and function of venom glands of some poisonous snakes and their venoms. In his studies, he got the results, which are fundamentally different from the conventional concept of 30s - 70s of the XX century. Unfortunately, among physicians this concept has not changed up today. At that time it was thought that the poisons of Viperidae snakes are almost completely hemotoxic, and poisons of Elapidae (cobra are almost neurotoxic. But A.M.Zaharov found out, that poisons of both types of snakes (Viperidae and Elapidae include three groups of substances: hemotoxins, neurotoxins and non-toxic component – hyaluronidase. Each of these groups of substances is produced by independent part of venom glands and has its own special effect. Neurotoxins act on the central nervous system (mainly the respiratory center, but are greatly destroyed by means of the blood antigen properties and cannot pass through the hematoencephalic barrier. Hyaluronidase , connecting with neurotoxins, has an important property – to "smuggle" neurotoxins through the hematoencephalic barrier exactly into the target organ – the respiratory center in the central nervous system. In this case, neurotoxin enters the respiratory center not through the blood and lymph vessels, but directly through the nerve channel, through synapsis. The main function of hemotoxins is not to kill the victim, but to protect neurotoxins and hyaluronidase from the destructive activity of the victim's blood. Therefore, the target of the poisons of Viperidae and Elapidae snakes is the central nervous system of victims, but Elapidae has almost no hemotoxins. That’s why their striking effect can be achieved only by a strong increase in the amount of neurotoxins and hyaluronidase. Hemotoxins of Viperidae venoms permits to reduce the amount of
Frezzatti, Rodrigo; Silveira, Paulo Flavio
Background Acute renal failure is one of the most serious complications of envenoming resulting from Crotalus durissus terrificus bites. This study evaluated the relevance of hyperuricemia and oxidative stress and the effects of allopurinol and probenecid in renal dysfunction caused by direct nephrotoxicity of C. d. terrificus venom. Methodology/Principal Findings Hematocrit, protein, renal function and redox status were assessed in mice. High ratio of oxidized/reduced glutathione and hyperuricemia induced by C. d. terrificus venom were ameliorated by both, allopurinol or probenecid, but only allopurinol significantly reduced the lethality caused by C. d. terrificus venom. The effectiveness of probenecid is compromised probably because it promoted hypercreatinemia and hypocreatinuria and worsed the urinary hypo-osmolality in envenomed mice. In turn, the highest effectiveness of allopurinol might be due to its ability to diminish the intracellular formation of uric acid. Conclusions/Significance Data provide consistent evidences linking uric acid with the acute renal failure induced by C. d. terrificus venom, as well as that this envenoming in mice constitutes an attractive animal model suitable for studying the hyperuricemia and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy. PMID:21909449
Frezzatti, Rodrigo; Silveira, Paulo Flavio
Acute renal failure is one of the most serious complications of envenoming resulting from Crotalus durissus terrificus bites. This study evaluated the relevance of hyperuricemia and oxidative stress and the effects of allopurinol and probenecid in renal dysfunction caused by direct nephrotoxicity of C. d. terrificus venom. Hematocrit, protein, renal function and redox status were assessed in mice. High ratio of oxidized/reduced glutathione and hyperuricemia induced by C. d. terrificus venom were ameliorated by both, allopurinol or probenecid, but only allopurinol significantly reduced the lethality caused by C. d. terrificus venom. The effectiveness of probenecid is compromised probably because it promoted hypercreatinemia and hypocreatinuria and worsed the urinary hypo-osmolality in envenomed mice. In turn, the highest effectiveness of allopurinol might be due to its ability to diminish the intracellular formation of uric acid. Data provide consistent evidences linking uric acid with the acute renal failure induced by C. d. terrificus venom, as well as that this envenoming in mice constitutes an attractive animal model suitable for studying the hyperuricemia and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy.
Full Text Available BACKGROUND: Acute renal failure is one of the most serious complications of envenoming resulting from Crotalus durissus terrificus bites. This study evaluated the relevance of hyperuricemia and oxidative stress and the effects of allopurinol and probenecid in renal dysfunction caused by direct nephrotoxicity of C. d. terrificus venom. METHODOLOGY/PRINCIPAL FINDINGS: Hematocrit, protein, renal function and redox status were assessed in mice. High ratio of oxidized/reduced glutathione and hyperuricemia induced by C. d. terrificus venom were ameliorated by both, allopurinol or probenecid, but only allopurinol significantly reduced the lethality caused by C. d. terrificus venom. The effectiveness of probenecid is compromised probably because it promoted hypercreatinemia and hypocreatinuria and worsed the urinary hypo-osmolality in envenomed mice. In turn, the highest effectiveness of allopurinol might be due to its ability to diminish the intracellular formation of uric acid. CONCLUSIONS/SIGNIFICANCE: Data provide consistent evidences linking uric acid with the acute renal failure induced by C. d. terrificus venom, as well as that this envenoming in mice constitutes an attractive animal model suitable for studying the hyperuricemia and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy.
Ana M. Moura-da-Silva
Full Text Available Snake venom metalloproteinases (SVMPs are abundant in the venoms of vipers and rattlesnakes, playing important roles for the snake adaptation to different environments, and are related to most of the pathological effects of these venoms in human victims. The effectiveness of SVMPs is greatly due to their functional diversity, targeting important physiological proteins or receptors in different tissues and in the coagulation system. Functional diversity is often related to the genetic diversification of the snake venom. In this review, we discuss some published evidence that posit that processing and post-translational modifications are great contributors for the generation of functional diversity and for maintaining latency or inactivation of enzymes belonging to this relevant family of venom toxins.
Chetty, Navinisha; Du, Amanda; Hodgson, Wayne C; Winkel, Ken; Fry, Bryan G
We examined the neurotoxicity of the following sea snake venoms: Enhydrina schistosa (geographical variants from Weipa and Malaysia), Lapemis curtus (Weipa and Malaysia), Laticauda colubrina, Aipysurus laevis, Aipysurus fuscus and Aipysurus foliosquamatus. Venom from a terrestrial snake, Notechis scutatus (tiger snake), was used as a reference. All venoms (1 and 3 microg/ml) abolished indirect twitches of the chick biventer cervicis muscle and significantly inhibited responses to ACh (1 mM) and CCh (20 microM), but not KCl (40 mM), indicating the presence of post-synaptic toxins. Prior administration (10 min) of CSL sea snake antivenom (1 unit/ml) attenuated the twitch blockade produced by N. scutatus venom and all sea snake venoms (1 microg/ml). Prior administration (10 min) of CSL tiger snake antivenom (1 unit/ml) attenuated the twitch blockade of all venoms except those produced by E. schistosa (Malaysia and Weipa) and A. foliosquamatus. Administration of CSL sea snake antivenom (1 unit/ml) at t90 (i.e. time at which 90% inhibition of initial twitch height occurred) reversed the inhibition of twitches (20-50%) produced by the sea snake venoms (1 microg/ml) but not by N. scutatus venom (1 microg/ml). CSL tiger snake antivenom (1 unit/ml) administered at t90 produced only minor reversal (i.e. 15-25%) of the twitch blockade caused by L. curtus (Weipa), A. foliosquamatus, L. colubrina and A. laevis venoms (1 microg/ml). Differences in the rate of reversal of the neurotoxicity produced by the two geographical variants of E. schistosa venom, after addition of CSL sea snake antivenom, indicate possible differences in venom components. This study shows that sea snake venoms contain potent post-synaptic activity that, despite the significant genetic distances between the lineages, can be neutralised with CSL sea snake antivenom. However, the effects of CSL tiger snake antivenom are more variable.
St Pierre, Liam; Birrell, Geoff W; Earl, Stephen T; Wallis, Tristan P; Gorman, Jeffrey J; de Jersey, John; Masci, Paul P; Lavin, Martin F
Included among the more than 300 species of elapid snakes worldwide is the Australian genus Demansia, or whip snakes. Despite evidence to suggest adverse clinical outcomes from envenomation by these snakes, together with confusion on their true phylogenetic relationship to other Australian elapids, not a single toxin sequence has previously been reported from the venom of a Demansia species. We describe here a combined proteomic and transcriptomic approach characterizing the venom from the black whip snake, Demansia vestigiata. A total of 13 distinct toxin families were identified, including homologues of all of the major toxic components previously reported from the venom of other Australian elapids, such as factor X-like prothrombin activators, neurotoxins, phospholipases, cysteine rich secretory proteins, textilinin-like molecules, nerve growth factors, l-amino acid oxidases, vespryns, 5' nucleotidases, metalloproteinases, and C-type lectins as well as a novel dipeptidyl peptidase family. Phylogenetic analysis of these sequences revealed an early evolutionary split of the black whip snake from all other characterized Australian snakes, with a low degree of sequence identity between D. vestigiata and the other snakes, across all toxin families. The results of this study have important implications not only for the further characterization of venom from whip snakes, but also for our understanding of the evolutionary relationship of Australian snake species.
Full Text Available BACKGROUND: The variation of venom composition with geography is an important aspect of intraspecific variability in the Vipera genus, although causes of this variability remain unclear. The diversity of snake venom is important both for our understanding of venomous snake evolution and for the preparation of relevant antivenoms to treat envenomations. A geographic intraspecific variation in snake venom composition was recently reported for Vipera aspis aspis venom in France. Since 1992, cases of human envenomation after Vipera aspis aspis bites in south-east France involving unexpected neurological signs were regularly reported. The presence of genes encoding PLA(2 neurotoxins in the Vaa snake genome led us to investigate any neurological symptom associated with snake bites in other regions of France and in neighboring countries. In parallel, we used several approaches to characterize the venom PLA(2 composition of the snakes captured in the same areas. METHODOLOGY/PRINCIPAL FINDINGS: We conducted an epidemiological survey of snake bites in various regions of France. In parallel, we carried out the analysis of the genes and the transcripts encoding venom PLA(2s. We used SELDI technology to study the diversity of PLA(2 in various venom samples. Neurological signs (mainly cranial nerve disturbances were reported after snake bites in three regions of France: Languedoc-Roussillon, Midi-Pyrénées and Provence-Alpes-Côte d'Azur. Genomes of Vipera aspis snakes from south-east France were shown to contain ammodytoxin isoforms never described in the genome of Vipera aspis from other French regions. Surprisingly, transcripts encoding venom neurotoxic PLA(2s were found in snakes of Massif Central region. Accordingly, SELDI analysis of PLA(2 venom composition confirmed the existence of population of neurotoxic Vipera aspis snakes in the west part of the Massif Central mountains. CONCLUSIONS/SIGNIFICANCE: The association of epidemiological studies to
Full Text Available Aim: Evaluating the epidemiologic characteristics and management of snake bites presenting to emergency departments. Material and Method: In this retrospective study 74 cases of snakebites admitted to Emergency Department of Diyarbakir Training and Research Hospital between 2008 and 2009 were retrospectively evaluated. Results: Fourty-six (62.2% of patients were male and 28 (37.8% were female. Mean age of the study population was 34.85±19.17 (min 7- max 80 years. Most of the snakebites occurred between 18.00 to 06.00 hours and at home (73%. 79.7% of snake bites occurred to upper extremities. %93 of cases had intravenous administration of antivenin (one dose. Neither none of the patients needed recurrent administration. Discussion: Snake bites are still a major public health problem especially in rural areas. Particularly emergency care physicians should be adequately capable and sophisticated in multidisciplinary management of snake bites.
Otero, R; Guillermo Osorio, R; Valderrama, R; Augusto Giraldo, C
We compared several pharmacological and enzymatic effects induced by 11 snake venoms from seven species, six of them from different geographic areas of Antioquia and Choco, north-west of Colombia, South America (Bothrops atrox, B. nasutus, B. schlegelii, B. punctatus, Lachesis muta, Micrurus mipartitus), and Crotalus durissus terrificus venom, from specimens captured in other provinces of the country (Tolima, Huila, Meta and Atlantico). Differences were observed in edema-forming, hemorrhage, defibrination, indirect hemolysis, myonecrosis, proteolysis and lethal activity between venoms from different genera or species, as well as according to the geographic area of origin in B. atrox and B. nasutus snake venoms. Bothrops venoms, in particular B. atrox and L. muta, produced major local effects. All of the venoms, including M. mipartitus, had myotoxic effects. The most defibrinating venoms were B. atrox, L. muta, B. punctatus and C. d. terrificus. All of the venoms had indirect hemolytic activity; the venom of M. mipartitus being greatest. The most lethal venoms were those of C. d. terrificus and M. mipartitus. Within Bothrops species, the venom of B. schlegelii was the least active in terms of local and systemic pathologic effects.
Welton, Ronelle E; Liew, Danny; Braitberg, George
It has been over 20 years since a national review of recorded deaths from snake envenoming. The present study aimed to provide an updated review of the epidemiology of deaths from snake bites in Australia. Deaths were identified from January 2000 to December 2016 from the National Coronial Information System. Cases identified due to snakes were extracted with data on coronial findings, autopsy and police records. Thirty five deaths (2.2 per year) were ascribed or antecedent to a snake bite. Sixteen cases were attributed to snake bite/envenoming as leading directly to death, with other direct causes of death being multiple organ failure (n = 3), intracerebral haemorrhage (n = 2), cerebral hypoxia or anoxia (n = 3), cardiac arrest (n = 1), complications of snake bite (n = 3) or brain stem death (n = 1). Four cases did not have a snake bite indicated in the case history, with an initial diagnosis of either hyperthermia, stroke, gastroenteritis and a horse accident. The median age was 46.5 years (range 1.5-70 years), and 74% were males (n = 25). The time from bite to death varied from 1 h to 19 days. Fifty four percent of bites occurred at the person's residence (n = 1), with 17 being in an urban environment. Death from snake bite remains rare in Australia, and has maintained a steady rate for over 20 years. Usually considered a 'rural issue', and with varying recorded causes of death, a nationally co-ordinated effort to further review the national picture of envenoming in Australia can inform education and resource needs within state and local contexts. Copyright © 2017 Elsevier Ltd. All rights reserved.
Brand, Guilherme D; Salbo, Rune; Jørgensen, Thomas J D
DM43 is a circulating dimeric antitoxin isolated from Didelphis aurita, a South American marsupial naturally immune to snake envenomation. This endogenous inhibitor binds non-covalently to jararhagin, the main hemorrhagic metalloproteinase from Bothrops jararaca snake venom, and efficiently...
Graham, Robert Leslie James; Graham, Ciaren; Theakston, David; McMullan, Geoff; Shaw, Chris
Research into snake venom components has intensified over the last number of decades, particularly that work directed towards the discovery of novel agents with potential applications in clinical therapy. In the present study we report, for the first time, defined patterns observed in the G-50 chromatographic elution profiles from 30 snake venoms taken from Elapidae and Viperidae families, as well as previously unreported patterns within subfamilies of these snake species. Development of this chromatographic technique thus offers a rapid method for the general classification of snakes within these families as well as providing insights into hitherto uncharacterised trends within the venoms of snake subfamilies that have opened new avenues for further investigation.
Hart, A J; Hodgson, W C; O'Leary, M; Isbister, G K
Myotoxicity is a common clinical effect of snake envenoming and results from either local or systemic myotoxins in snake venoms. Although numerous myotoxins have been isolated from snake venoms, there has been limited study on the relationship between the time course of venom concentrations (pharmacokinetics) and the time course of muscle injury measured as a rise in creatine kinase (CK) (pharmacodynamics). The aim of this study was to develop an in vivo model of myotoxicity to investigate the time course of myotoxicity and the effect of antivenom. Anesthetised rats were administered Pseudechis australis (mulga snake) venom either through i.v., i.m. or s.d. route, including a range of doses (5-100 μg/kg). Serial blood samples were collected for measurement of venom using enzyme immunoassay and measurement of CK and creatinine. Antivenom was administered before, 1 and 6 h after venom administration to investigate its effect on muscle injury. Plots of venom and CK versus time were made and the area under the curve (AUC) was calculated. There was a significant dose-dependent increase in CK concentration after administration of P. australis venom, which was greatest for i.v. administration. Timed measurement of venom concentrations showed a rapid absorption through s.d. and i.m. routes and a delayed rise in CK concentrations following any route. Antivenom prevented myotoxicity shown by a decrease in the CK AUC, which was most effective if given earliest. There was a rise in creatinine following i.v. venom administration. The study shows the delayed relationship between venom absorption and the rise in CK, consistent with the delayed onset of myotoxicity in human envenoming. Antivenom prevented myotoxicity more effectively if given earlier.
Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C
Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms.
Sánchez, Elda E.; Lopez-Johnston, Juan C.; Rodríguez-Acosta, Alexis; Pérez, John C.
Elapid snakes throughout the world are considered very lethal containing neurotoxic venoms that affect the nervous system. When humans are envenomated it is considered a serious medical emergency, and antivenom is the main form of treatment considered, in spite of the fact that some patients may only survive under intensive therapy treatment such as respiratory support. Coral snakes are part of the family Elapidae and envenomations by these snakes are very low (< 2% of total snakebites) in mo...
A 22-year old man was bitten by a snake on his scrotum. This interesting and unusual case occurred in the rural area of District Aligarh, India. The niqueness of the case lies in the fact that scrotum is an extremely rare and unusual site for snake bite. Further, with negligible local signs of envenoming the patient presented ...
Gasanov, Sardar E; Dagda, Ruben K; Rael, Eppie D
Snake venom toxins are responsible for causing severe pathology and toxicity following envenomation including necrosis, apoptosis, neurotoxicity, myotoxicity, cardiotoxicity, profuse hemorrhage, and disruption of blood homeostasis. Clinically, snake venom toxins therefore represent a significant hazard to snakebite victims which underscores the need to produce more efficient anti-venom. Some snake venom toxins, however, have great potential as drugs for treating human diseases. In this review, we discuss the biochemistry, structure/function, and pathology induced by snake venom toxins on human tissue. We provide a broad overview of cobra venom cytotoxins, catalytically active and inactive phospholipase A2s (PLA2s), and Zn2+-dependent metalloproteinases. We also propose biomedical applications whereby snake venom toxins can be employed for treating human diseases. Cobra venom cytotoxins, for example, may be utilized as anti-cancer agents since they are efficient at destroying certain types of cancer cells including leukemia. Additionally, increasing our understanding of the molecular mechanism(s) by which snake venom PLA2s promote hydrolysis of cell membrane phospholipids can give insight into the underlying biomedical implications for treating autoimmune disorders that are caused by dysregulated endogenous PLA2 activity. Lastly, we provide an exhaustive overview of snake venom Zn2+-dependent metalloproteinases and suggest ways by which these enzymes can be engineered for treating deep vein thrombosis and neurodegenerative disorders. PMID:24949227
Gasanov, Sardar E; Dagda, Ruben K; Rael, Eppie D
Snake venom toxins are responsible for causing severe pathology and toxicity following envenomation including necrosis, apoptosis, neurotoxicity, myotoxicity, cardiotoxicity, profuse hemorrhage, and disruption of blood homeostasis. Clinically, snake venom toxins therefore represent a significant hazard to snakebite victims which underscores the need to produce more efficient anti-venom. Some snake venom toxins, however, have great potential as drugs for treating human diseases. In this review, we discuss the biochemistry, structure/function, and pathology induced by snake venom toxins on human tissue. We provide a broad overview of cobra venom cytotoxins, catalytically active and inactive phospholipase A2s (PLA2s), and Zn(2+)-dependent metalloproteinases. We also propose biomedical applications whereby snake venom toxins can be employed for treating human diseases. Cobra venom cytotoxins, for example, may be utilized as anti-cancer agents since they are efficient at destroying certain types of cancer cells including leukemia. Additionally, increasing our understanding of the molecular mechanism(s) by which snake venom PLA2s promote hydrolysis of cell membrane phospholipids can give insight into the underlying biomedical implications for treating autoimmune disorders that are caused by dysregulated endogenous PLA2 activity. Lastly, we provide an exhaustive overview of snake venom Zn(2+)-dependent metalloproteinases and suggest ways by which these enzymes can be engineered for treating deep vein thrombosis and neurodegenerative disorders.
Aziz, Hassan; Rhee, Peter; Pandit, Viraj; Tang, Andrew; Gries, Lynn; Joseph, Bellal
Animal and human bite wounds represent a significant global health issue. In the United States, animal and human bites are a very common health issue, causing significant morbidity and even, in rare scenarios, mortality. Most animal bite wounds in the United States are caused by dogs, with cat bites being a distant second. Human bite wounds constitute a dominant subset of all bite wounds. Several studies of bite wounds have reported improved outcomes with early diagnosis and immediate treatment. However, the available literature on the initial treatment provides a plethora of conflicting opinions and results. In this review, our aim was to identify and assess the current evidence on the management of animal (dog, cat, insects, scorpions, and snakes) and human bite wounds. Review article, level III.
Gay, Carolina; Sanz, Libia; Calvete, Juan J.; Pla, Davinia
Snake species within genus Bothrops are responsible for more than 80% of the snakebites occurring in South America. The species that cause most envenomings in Argentina, B. diporus, is widely distributed throughout the country, but principally found in the Northeast, the region with the highest rates of snakebites. The venom proteome of this medically relevant snake was unveiled using a venomic approach. It comprises toxins belonging to fourteen protein families, being dominated by PI- and PIII-SVMPs, PLA2 molecules, BPP-like peptides, L-amino acid oxidase and serine proteinases. This toxin profile largely explains the characteristic pathophysiological effects of bothropic snakebites observed in patients envenomed by B. diporus. Antivenomic analysis of the SAB antivenom (Instituto Vital Brazil) against the venom of B. diporus showed that this pentabothropic antivenom efficiently recognized all the venom proteins and exhibited poor affinity towards the small peptide (BPPs and tripeptide inhibitors of PIII-SVMPs) components of the venom. PMID:26712790
Gay, Carolina; Sanz, Libia; Calvete, Juan J; Pla, Davinia
Snake species within genus Bothrops are responsible for more than 80% of the snakebites occurring in South America. The species that cause most envenomings in Argentina, B. diporus, is widely distributed throughout the country, but principally found in the Northeast, the region with the highest rates of snakebites. The venom proteome of this medically relevant snake was unveiled using a venomic approach. It comprises toxins belonging to fourteen protein families, being dominated by PI- and PIII-SVMPs, PLA₂ molecules, BPP-like peptides, L-amino acid oxidase and serine proteinases. This toxin profile largely explains the characteristic pathophysiological effects of bothropic snakebites observed in patients envenomed by B. diporus. Antivenomic analysis of the SAB antivenom (Instituto Vital Brazil) against the venom of B. diporus showed that this pentabothropic antivenom efficiently recognized all the venom proteins and exhibited poor affinity towards the small peptide (BPPs and tripeptide inhibitors of PIII-SVMPs) components of the venom.
Sanz, Libia; Pla, Davinia; Pérez, Alicia; Rodríguez, Yania; Zavaleta, Alfonso; Salas, Maria; Lomonte, Bruno; Calvete, Juan J
The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs) constitute, both in number of isoforms (~30) and total abundance (93.6% of the venom proteome), the major protein family of the desert coral snake venom. Phospholipases A₂ (PLA₂s; seven isoforms, 4.1% of the venom proteome), 1-3 Kunitz-type proteins (1.6%), and 1-2 l-amino acid oxidases (LAO, 0.7%) complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA₂-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae) venoms suggests that the 3FTx/PLA₂ dichotomy may be widely distributed among Elapidae venoms.
Sanz, Libia; Pla, Davinia; Pérez, Alicia; Rodríguez, Yania; Zavaleta, Alfonso; Salas, Maria; Lomonte, Bruno; Calvete, Juan J.
The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs) constitute, both in number of isoforms (~30) and total abundance (93.6% of the venom proteome), the major protein family of the desert coral snake venom. Phospholipases A2 (PLA2s; seven isoforms, 4.1% of the venom proteome), 1–3 Kunitz-type proteins (1.6%), and 1–2 l-amino acid oxidases (LAO, 0.7%) complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA2-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae) venoms suggests that the 3FTx/PLA2 dichotomy may be widely distributed among Elapidae venoms. PMID:27338473
Full Text Available The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs constitute, both in number of isoforms (~30 and total abundance (93.6% of the venom proteome, the major protein family of the desert coral snake venom. Phospholipases A2 (PLA2s; seven isoforms, 4.1% of the venom proteome, 1–3 Kunitz-type proteins (1.6%, and 1–2 l-amino acid oxidases (LAO, 0.7% complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA2-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae venoms suggests that the 3FTx/PLA2 dichotomy may be widely distributed among Elapidae venoms.
Al-Asmari, Abdulrahman K.; Abbasmanthiri, Rajamohamed; Abdo Osman, Nasreddien M.; Siddiqui, Yunus; Al-Bannah, Faisal Ahmed; Al-Rawi, Abdulgadir M.; Al-Asmari, Sarah A.
Background Venoms of two cobras, four vipers, a standard antibiotic and an antimycotic, were evaluated comparatively, as antimicrobials. Methods: Six venom concentrations and three of the standard antibiotic and the antimycotic were run in micro-dilution and diffusion plates against the microorganisms. RESULTS: Echis pyramidum, Echis coloratus and Cerastes cerastes gasperettii highest venom concentrations gave significant growth inhibition zones (GIZ) with respect to a negative control, except Bitis arietans, whose concentrations were significant. The cobra Walterinnesia aegyptia had significant venom concentrations more than Naja haje arabica. The Staphylococcus aureus Methicillin Resistant (MRSA) bacterium was the most susceptible, with a highly (P venoms (P > 0.05). The antibiotic Vancomycin was more effective than snake venoms though, they were more efficient in inhibiting growth of the resistant Pseudomonas aeruginosa. This antibiotic was also inactive against the fungus, whilst its specific antifungal Fungizone was highly efficient with no antibacterial activity. Conclusions: These findings showed that snake venoms had antibacterial activity comparable to antibiotics, with a directly proportional relationship of venom concentration and GIZ, though, they were more efficient in combatting resistant types of bacteria. Both venoms and the standard antibiotic, showed no antifungal benefits. PMID:26668657
Munawar, Aisha; Trusch, Maria; Georgieva, Dessislava; Hildebrand, Diana; Kwiatkowski, Marcel; Behnken, Henning; Harder, Sönke; Arni, Raghuvir; Spencer, Patrick; Schlüter, Hartmut; Betzel, Christian
Elapid snake venom is a highly valuable, but till now mainly unexplored, source of pharmacologically important peptides. We analyzed the peptide fractions with molecular masses up to 10 kDa of two elapid snake venoms-that of the African cobra, N. m. mossambica (genus Naja), and the Peninsula tiger snake, N. scutatus, from Kangaroo Island (genus Notechis). A combination of chromatographic methods was used to isolate the peptides, which were characterized by combining complimentary mass spectrometric techniques. Comparative analysis of the peptide compositions of two venoms showed specificity at the genus level. Three-finger (3-F) cytotoxins, bradykinin-potentiating peptides (BPPs) and a bradykinin inhibitor were isolated from the Naja venom. 3-F neurotoxins, Kunitz/basic pancreatic trypsin inhibitor (BPTI)-type inhibitors and a natriuretic peptide were identified in the N. venom. The inhibiting activity of the peptides was confirmed in vitro with a selected array of proteases. Cytotoxin 1 (P01467) from the Naja venom might be involved in the disturbance of cellular processes by inhibiting the cell 20S-proteasome. A high degree of similarity between BPPs from elapid and viperid snake venoms was observed, suggesting that these molecules play a key role in snake venoms and also indicating that these peptides were recruited into the snake venom prior to the evolutionary divergence of the snakes.
Full Text Available Snake venoms comprise a highly complex mixture of proteins, which requires for their characterization the use of versatile two-dimensional electrophoresis techniques. In the present study, venoms obtained from eight snakes (Ophiophagus hannah, Naja kaouthia, Naja sumatrana, Bungarus fasciatus, Trimeresurus sumatranus, Tropidolaemus wagleri, Enhydrina schistosa and Calloselasma rhodostoma commonly found in Malaysia were separated based on two independent properties, isoelectric point (pI and molecular weight (MW. Many differences in snake venoms at the inter-family, inter-subfamily, inter-genus and inter-species levels were revealed. Notably, proteins from individuals of the Viperidae family - Trimeresurus sumatranus, Tropidolaemus wagleri and Calloselasma rhodostoma - were found to be numerous and scattered by the two-dimensional gel electrophoresis (2DE specifically in regions between 37 and 100 kDa compared to the Elapidae venom proteins. The latter were clustered at the basic and lower molecular mass region (less than 20 kDa. Trains of spots were commonly observed, indicating that these proteins may be derived from post-translational modifications. Ophiophagus hannah (Elapidae revealed a great amount of protein spots in the higher molecular mass range when compared to Enhydrina schistosa, Naja kaouthia, Naja sumatrana and Bungarus fasciatus. Overall 2DE showed large differences in the venom profile of each species, which might be employed as an ancillary tool to the identification of venomous snake species.
Munawar, Aisha; Trusch, Maria; Georgieva, Dessislava; Hildebrand, Diana; Kwiatkowski, Marcel; Behnken, Henning; Harder, Soenke; Arni, Raghuvir; Spencer, Patrick; Schlueter, Hartmut; Betzel, Christian
Elapid snake venom is a highly valuable, but till now mainly unexplored, source of pharmacologically important peptides. We analyzed the peptide fractions with molecular masses up to 10 kDa of two elapid snake venoms-that of the African cobra, N. m. mossambica (genus Naja), and the Peninsula tiger
Corbett, Bryan; Clark, Richard F
Native US snakes that produce clinically significant envenomation can be divided into 2 groups, crotalids and elapids. The crotalids include rattlesnakes, cottonmouths, and copperheads. Crotalid envenomation can result in significant local tissue damage as well as thrombocytopenia and coagulopathy. Rarely are bites fatal. Native US elapids are all coral snakes that possess neurotoxic venom that can cause weakness, respiratory paralysis, and rarely death. Treatment of both types of envenomation revolves around general supportive care and antivenom administration when indicated. Previously advocated treatments, such as tourniquets, venom extraction, and bite site excision are not recommended. Copyright © 2016 Elsevier Inc. All rights reserved.
Miriéle Cristina Ferraz
Full Text Available We confirmed the ability of the triterpenoid betulin to protect against neurotoxicity caused by Bothrops jararacussu snake venom in vitro in mouse isolated phrenic nerve-diaphragm (PND preparations and examined its capability of in vivo protection using the rat external popliteal/sciatic nerve-tibialis anterior (EPSTA preparation. Venom caused complete, irreversible blockade in PND (40 μg/mL, but only partial blockade (~30% in EPSTA (3.6 mg/kg, i.m. after 120 min. In PND, preincubation of venom with commercial bothropic antivenom (CBA attenuated the venom-induced blockade, and, in EPSTA, CBA given i.v. 15 min after venom also attenuated the blockade (by ~70% in both preparations. Preincubation of venom with betulin (200 μg/mL markedly attenuated the venom-induced blockade in PND; similarly, a single dose of betulin (20 mg, i.p., 15 min after venom virtually abolished the venom-induced decrease in contractility. Plasma creatine kinase activity was significantly elevated 120 min after venom injection in the EPSTA but was attenuated by CBA and betulin. These results indicate that betulin given i.p. has a similar efficacy as CBA given i.v. in attenuating the neuromuscular effects of B. jararacussu venom in vivo and could be a useful complementary measure to antivenom therapy for treating snakebite.
Ferraz, Miriéle Cristina; de Oliveira, Jhones Luiz; de Oliveira Junior, Joel Reis; Cogo, José Carlos; dos Santos, Márcio Galdino; Franco, Luiz Madaleno; Puebla, Pilar; Ferraz, Helena Onishi; Ferraz, Humberto Gomes; da Rocha, Marisa Maria Teixeira; Hyslop, Stephen
We confirmed the ability of the triterpenoid betulin to protect against neurotoxicity caused by Bothrops jararacussu snake venom in vitro in mouse isolated phrenic nerve-diaphragm (PND) preparations and examined its capability of in vivo protection using the rat external popliteal/sciatic nerve-tibialis anterior (EPSTA) preparation. Venom caused complete, irreversible blockade in PND (40 μg/mL), but only partial blockade (~30%) in EPSTA (3.6 mg/kg, i.m.) after 120 min. In PND, preincubation of venom with commercial bothropic antivenom (CBA) attenuated the venom-induced blockade, and, in EPSTA, CBA given i.v. 15 min after venom also attenuated the blockade (by ~70% in both preparations). Preincubation of venom with betulin (200 μg/mL) markedly attenuated the venom-induced blockade in PND; similarly, a single dose of betulin (20 mg, i.p., 15 min after venom) virtually abolished the venom-induced decrease in contractility. Plasma creatine kinase activity was significantly elevated 120 min after venom injection in the EPSTA but was attenuated by CBA and betulin. These results indicate that betulin given i.p. has a similar efficacy as CBA given i.v. in attenuating the neuromuscular effects of B. jararacussu venom in vivo and could be a useful complementary measure to antivenom therapy for treating snakebite. PMID:26633987
Bin Asd, Muhammad Hassham Hassan; Iqbal, Muhammad; Akram, Muhammad Rouf; Khawaja, Naeem Raza; Muneer, Saiqa; Shabbir, Muhammad Zubair; Khan, Muhammad Saqib; Murtaza, Ghulam; Hussain, Izhar
Present study was carried out regarding enzymatic assay for 5'-nucleotidase enzymes present in snake venom Naja naja karachiensis and to evaluate twenty eight medicinal plants as their antidotes. Elevated enzymatic activities i.e., 119, 183, 262 and 335 U/mL were observed in 10, 20, 30 and 40 µg of crude venom, respectively, in dose dependent manner. Among various plant extracts only two (Bauhinia vaiiegate L. and Citms linion (L.) Burm. f.) were found 94% effective at 160 µg to neutralize 112 U/mL activities (p 0.5) while reference standard was proved 93.2% useful at 80 pg to halt 111 U/mL activities. Cedrus deodara G. Don, Enicostemna hyssopifolium (Willd.) Verdoom, Terminalia arjuma Wight & Am. and Zingiber officinalis Rosc. (at 160 µg) were found ≥90% effective (0.5 ≥ p ≥ 0.1) while Citrulus colocynthis, Fogonia cretica L., Rhazya stticta Dcne and Stenolobiun stans (L.) D. Don (at 320 µg) were proved 90% effective (0.05 ≥ p ≥ 0.02). The remaining plant extracts were observed abortive (p ≥ 0.001) in neutralization of 5'-nucleotidases enzymatic actions. This study emphasizes further characterization of active plant extracts to further explore the antivenom influences of these herbal remedies against deleterious effects produced by 5'-nucleotidase enzymes after snake bite envenomation.
Abdel-Aty, Azza M; Wahby, Ahmed F
New five P-III snake venom metalloproteinases (SVMPs): EpyB2 (62 kDa), EpyB3 (62+23 kDa), EpyB4 (60 kDa), EpyB5 (67 kDa) and EpyB6 (66 kDa) of the most dangerous viper, Echis pyramidum pyramidum (Epy), were purified and characterized in a set of biochemical assays. The SVMPs were purified by applying a protocol of two successive chromatographic steps. Three purified SVMPs "EpyB2, EpyB4, and EpyB5" have hemorrhagic activity with MHDs, 7 μg, 7.6 μg and 15 μg, respectively; furthermore, they have high preference towards fibronectin, collagen, gelatin, fibrin and hemoglobin substrates compared with non-hemorrhagic SVMPs (EpyB3 and EpyB6). All the purified SVMPs showed remarkable thermal and pH stability, inhibited by metalloproteinase inhibitors and Zn(2+), Mn(2+), Ni(2+), Co(2+), Cu(2+), and Hg(2+). The purified SVMPs act as α-fibrinogenases, prothrombin activators and procoagulants. In conclusion, Epy venom has multiple SVMPs that are responsible for hemorrhagic events and thus represent a significant health hazard for victims of envenomation, however, they may be useful for treating diseases involving abnormal blood clot formation.
Oliveira, Fabiana da Rocha; Noronha, Maria das Dores Nogueira; Lozano, Jorge Luis Lopez
The coral snake Micrurus surinamensis, which is widely distributed throughout Amazonia, has a neurotoxic venom. It is important to characterize the biological and molecular properties of this venom in order to develop effective antitoxins. Toxins from the venom of M. surinamensis were analyzed by two-dimensional polyacrylamide gel electrophoresis and their neurotoxic effects in vivo were evaluated. Most proteins in the venom had masses < 14kDa, low phospholipase A2 activity, and no proteolytic activity. The toxins inhibited the coagulation cascade. The venom had neurotoxic effects in mice, with a median lethal dose upon intravenous administration of 700 µg/kg. Immunogenic studies revealed abundant cross-reactivity of antielapidic serum with 14kDa toxins and limited cross-reactivity with toxins < 10kDa. These results indicate that antielapidic serum against M. surinamensis venom has weak potency (0.35mg/ml) in mice.
Fabiana da Rocha Oliveira
Full Text Available Abstract INTRODUCTION: The coral snake Micrurus surinamensis, which is widely distributed throughout Amazonia, has a neurotoxic venom. It is important to characterize the biological and molecular properties of this venom in order to develop effective antitoxins. METHODS: Toxins from the venom of M. surinamensis were analyzed by two-dimensional polyacrylamide gel electrophoresis and their neurotoxic effects in vivo were evaluated. RESULTS AND CONCLUSIONS: Most proteins in the venom had masses < 14kDa, low phospholipase A2 activity, and no proteolytic activity. The toxins inhibited the coagulation cascade. The venom had neurotoxic effects in mice, with a median lethal dose upon intravenous administration of 700 µg/kg. Immunogenic studies revealed abundant cross-reactivity of antielapidic serum with 14kDa toxins and limited cross-reactivity with toxins < 10kDa. These results indicate that antielapidic serum against M. surinamensis venom has weak potency (0.35mg/ml in mice.
Nicolau, Carolina A; Carvalho, Paulo C; Junqueira-de-Azevedo, Inácio L M; Teixeira-Ferreira, André; Junqueira, Magno; Perales, Jonas; Neves-Ferreira, Ana Gisele C; Valente, Richard H
A large-scale proteomic approach was devised to advance the understanding of venom composition. Bothrops jararaca venom was fractionated by OFFGEL followed by chromatography, generating peptidic and proteic fractions. The latter was submitted to trypsin digestion. Both fractions were separately analyzed by reversed-phase nanochromatography coupled to high resolution mass spectrometry. This strategy allowed deeper and joint characterizations of the peptidome and proteome (proteopeptidome) of this venom. Our results lead to the identification of 46 protein classes (with several uniquely assigned proteins per class) comprising eight high-abundance bona fide venom components, and 38 additional classes in smaller quantities. This last category included previously described B. jararaca venom proteins, common Elapidae venom constituents (cobra venom factor and three-finger toxin), and proteins typically encountered in lysosomes, cellular membranes and blood plasma. Furthermore, this report is the most complete snake venom peptidome described so far, both in number of peptides and in variety of unique proteins that could have originated them. It is hypothesized that such diversity could enclose cryptides, whose bioactivities would contribute to envenomation in yet undetermined ways. Finally, we propose that the broad range screening of B. jararaca peptidome will facilitate the discovery of bioactive molecules, eventually leading to valuable therapeutical agents. Our proteopeptidomic strategy yielded unprecedented insights into the remarkable diversity of B. jararaca venom composition, both at the peptide and protein levels. These results bring a substantial contribution to the actual pursuit of large-scale protein-level assignment in snake venomics. The detection of typical elapidic venom components, in a Viperidae venom, reinforces our view that the use of this approach (hand-in-hand with transcriptomic and genomic data) for venom proteomic analysis, at the specimen
Pla, Davinia; Paiva, Owen K; Sanz, Libia; Beutler, Markus; Wright, Christine E; Calvete, Juan J; Williams, David J; Gutiérrez, José María
Karkar Island are attributed to bites by the Ikaheka snake. However, no specific antivenom is available for the treatment of M. ikaheka envenoming in Papua New Guinea. This study evaluated a panel of Australian bioCSL antivenoms for their paraspecific immunoreaction and neutralization of the toxic activities of M. ikaheka venom. All antivenoms exhibited strong immunorecognition of α-neurotoxins of the 3FTx family and neutralized the lethal, i.e. neurotoxic, and myotoxic activities of M. ikaheka venom. However, these antivenoms exhibited poor neutralization of PLA₂ and anticoagulant activities. This study suggests that the Australian antivenoms may provide paraspecific protection against M. ikaheka venom in humans, a hypothesis that demands studies aimed at assessing whether these antivenoms neutralize neurotoxicity and myotoxicity in the clinical setting. Copyright © 2014 Elsevier B.V. All rights reserved.
Full Text Available BACKGROUND Snake venom is well known to cause toxic damage to the kidneys (Schreiner and Maher, 1965. This study is an attempt to evaluate the snakebite-induced Acute Kidney Injury (AKI. MATERIALS AND METHODS 50 patients with snakebite-induced acute kidney injury were selected randomly and their clinical profile was assessed. Acute kidney injury was evaluated using noninvasive laboratory methods. Inclusion Criteria- 1. History of snakebite; 2. Presence of AKI. Exclusion Criteria- Pre-existing renal diseases, after establishing the diagnosis, patients were started on conservative treatment including ASV, blood/blood products and haemodialysis as required. RESULTS Out of 50 patients included in the study, majority of them were males (62% with mean age of presentation 43.8 ± 12.63 years. The mean interval between snakebite and presentation to hospital was 15.37 hours. In them, 98% patients presented with local signs of inflammation, 52% of patients presented with coagulation abnormality and 60% with decreased urine output. Comparison between good outcome (recovered from AKI and poor outcome (not recovered from AKI shows significant pvalue for ‘lapse of time in hours’ in presenting to the hospital after snakebite (p value 0.005 and ‘alternative treatment taken’ before coming to the hospital (p value 0.001. CONCLUSION Poisonous snakebites have common manifestations of cellulitis, abnormal coagulation profile and decreased urine output. Overall mortality due to snakebite-induced AKI is 6%. Patients who did not recover from AKI had lapse of time in presenting to the hospital and abnormal coagulation profile.
Mônica D. S. Barbosa
Full Text Available BACKGROUND: A new fibrin adhesive made of buffalo plasma-derived fibrinogen and a thrombin-like snake venom enzyme, has been successfully used to immobilize free gingival grafts. This case series histologically compared sutured grafts (control group with others immobilized by using the fibrin adhesive (experimental group. CASE DESCRIPTION: The grafts were placed in the contralateral mandibular bicuspids of 15 patients, so that each subject received one treatment of each type. Five biopsies of each group were collected at 7, 14 and 45 days of healing, which were histologically and morphometrically analyzed as regards the relative volume density of the different connective tissue components. RESULTS: The sites in the control group presented a higher inflammatory cell density at 7 days and a tendency towards a lower collagen density. In the experimental group, the grafts had an appearance of more advanced healing. Tissue maturity characteristics progressed until 14 and 45 days, but no difference between groups could be noted at these times. Conclusions: Within the limits of the present study, it may be suggested that the alternative fibrin adhesive tested could represent an alternative to sutures in gingival grafts procedures.
Ahmad, Mustaq, E-mail: firstname.lastname@example.org [University of Science and Technology, Bannu, (Pakistan). Department of Biotechnology; Weber, Andrea D.; Zanon, Graciane; Tavares, Luciana de C.; Ilha, Vinicius; Dalcol, Ionara I.; Morel, Ademir F., E-mail: email@example.com [Universidade Federal de Santa Maria, RS (Brazil). Dept. de Quimica
The in vitro activity of chelerythrine and lupeol, two metabolites isolated from Zanthoxylum rhoifolium were studied against the venom of the snake Bungarus sindanus (Elapidae). The venom, which is highly toxic to humans, consists mainly by the enzyme acetylcholinesterase (AChE). Both compounds showed activity against the venom, and the alkaloid chelerythrine presented higher activity than did triterpene lupeol. (author)
Heus, F.A.H.; Vonk, F.; Otvos, R.A.; Bruyneel, B.; Smit, A.B.; Lingeman, H.; Richardson, M.; Niessen, W.M.A.; Kool, J.
Venomous snakes have evolved their efficient venomous arsenals mainly to immobilize prey. The highly variable toxic peptides in these venoms target a myriad of neurotoxic and haemotoxic receptors and enzymes and comprise highly interesting candidates for drug discovery. Discovery of bioactive
Asad, Muhammad H H B; Durr-E-Sabih; Yaqab, Tahir; Murtaza, Ghulam; Hussain, Muhammad S; Hussain, Muhammad S; Nasir, Muhammad T; Azhar, Saira; Khan, Shujaat A; Hussain, Izhar
Phospholipases A2 (PLA2) are the most lethal and noxious component of Naja naja karachiensis venom. They are engaged to induce severe toxicities after their penetration in victims. Present study was designed to highlight hydrolytic actions of PLA. in an egg yolk mixture and to encounter their deleterious effects via medicinal plants of Pakistan. PLA2 were found to produce free fatty acids in a dose dependent manner. Venom at concentration of 0.1 mg was found to liberate 26.6 pmoles of fatty acids with a decline in pH1 of 0.2 owing to the presence of PLA2 (133 Unit/mg). When quantity of venom was increased up to 8 mg, it caused to release 133 pmoles of free fatty acids with a decrease in 1.0 pH due to abundance in PLA, (665 Unit/mg). The rest of other doses of venom (0.3-4.0 mg) was found to liberate fatty acids between these two upper and lower limits. Twenty eight medicinal plants (0.1-0.6 mg) were tried to abort PLA, hydrolytic action, however, all were found useful (50-100%) against PLA,. Bauhinia variegate L., Citrus limon (L.). Burm.f. Enicostemnma hyssopifolium (Willd.) Verdoorn, Ocimum sanctum. Psoralea corylifolia L. and Stenolobium stans (L.) D. Don were found excellent in switching off 100% phospholipases A, at their lowest concentration (0.1 mg). Three plants extract were found useful only at lower concentration (0.1 mg), however, their higher doses were seemed to aggravate venom response. Eight medicinal plants failed to neutralize PLA, rather their higher doses were found effective. Standard antidote and rest of other plants extract were able to show maximum of 50% efficiencies. Therefore, it is necessary to identify and isolate bioactive constituent(s) from above cited six medicinal plants to eradicate the problem of snake bite in the future.
Al-Asmari, Abdulrahman K; Abbasmanthiri, Rajamohamed; Abdo Osman, Nasreddien M; Siddiqui, Yunus; Al-Bannah, Faisal Ahmed; Al-Rawi, Abdulgadir M; Al-Asmari, Sarah A
Venoms of two cobras, four vipers, a standard antibiotic and an antimycotic, were evaluated comparatively, as antimicrobials. Six venom concentrations and three of the standard antibiotic and the antimycotic were run in micro-dilution and diffusion plates against the microorganisms. Echis pyramidum, Echis coloratus and Cerastes cerastes gasperettii highest venom concentrations gave significant growth inhibition zones (GIZ) with respect to a negative control, except Bitis arietans, whose concentrations were significant. The cobra Walterinnesia aegyptia had significant venom concentrations more than Naja haje arabica. The Staphylococcus aureus Methicillin Resistant (MRSA) bacterium was the most susceptible, with a highly (P 0.05). The antibiotic Vancomycin was more effective than snake venoms though, they were more efficient in inhibiting growth of the resistant Pseudomonas aeruginosa. This antibiotic was also inactive against the fungus, whilst its specific antifungal Fungizone was highly efficient with no antibacterial activity. These findings showed that snake venoms had antibacterial activity comparable to antibiotics, with a directly proportional relationship of venom concentration and GIZ, though, they were more efficient in combatting resistant types of bacteria. Both venoms and the standard antibiotic, showed no antifungal benefits.
Eduardo Coriolano De Oliveira
Full Text Available Snake venom is composed of a mixture of substances that caused in victims a variety of pathophysiological effects. Besides antivenom, literature has described plants able to inhibit injuries and lethal activities induced by snake venoms. This work describes the inhibitory potential of ethanol, hexane, ethyl acetate, or dichloromethane extracts and fractions from stem and leaves of Manilkara subsericea against in vivo (hemorrhagic and edema and in vitro (clotting, hemolysis, and proteolysis activities caused by Lachesis muta venom. All the tested activities were totally or at least partially reduced by M. subsericea. However, when L. muta venom was injected into mice 15 min first or after the materials, hemorrhage and edema were not inhibited. Thus, M. subsericea could be used as antivenom in snakebites of L. muta. And, this work also highlights Brazilian flora as a rich source of molecules with antivenom properties.
Laustsen, Andreas H; Gutiérrez, José María; Lohse, Brian; Rasmussen, Arne R; Fernández, Julián; Milbo, Christina; Lomonte, Bruno
The venom proteome of the monocled cobra, Naja kaouthia, from Thailand, was characterized by RP-HPLC, SDS-PAGE, and MALDI-TOF-TOF analyses, yielding 38 different proteins that were either identified or assigned to families. Estimation of relative protein abundances revealed that venom is dominated by three-finger toxins (77.5%; including 24.3% cytotoxins and 53.2% neurotoxins) and phospholipases A2 (13.5%). It also contains lower proportions of components belonging to nerve growth factor, ohanin/vespryn, cysteine-rich secretory protein, C-type lectin/lectin-like, nucleotidase, phosphodiesterase, metalloproteinase, l-amino acid oxidase, cobra venom factor, and cytidyltransferase protein families. Small amounts of three nucleosides were also evidenced: adenosine, guanosine, and inosine. The most relevant lethal components, categorized by means of a 'toxicity score', were α-neurotoxins, followed by cytotoxins/cardiotoxins. IgGs isolated from a person who had repeatedly self-immunized with a variety of snake venoms were immunoprofiled by ELISA against all venom fractions. Stronger responses against larger toxins, but lower against the most critical α-neurotoxins were obtained. As expected, no neutralization potential against N. kaouthia venom was therefore detected. Combined, our results display a high level of venom complexity, unveil the most relevant toxins to be neutralized, and provide prospects of discovering human IgGs with toxin neutralizing abilities through use of phage display screening. Copyright © 2015 Elsevier Ltd. All rights reserved.
Munawar, Aisha; Trusch, Maria; Georgieva, Dessislava; Hildebrand, Diana; Kwiatkowski, Marcel; Behnken, Henning; Harder, Sönke; Arni, Raghuvir; Spencer, Patrick; Schlüter, Hartmut; Betzel, Christian
Elapid snake venom is a highly valuable, but till now mainly unexplored, source of pharmacologically important peptides. We analyzed the peptide fractions with molecular masses up to 10 kDa of two elapid snake venoms—that of the African cobra, N. m. mossambica (genus Naja), and the Peninsula tiger snake, N. scutatus, from Kangaroo Island (genus Notechis). A combination of chromatographic methods was used to isolate the peptides, which were characterized by combining complimentary mass spectrometric techniques. Comparative analysis of the peptide compositions of two venoms showed specificity at the genus level. Three-finger (3-F) cytotoxins, bradykinin-potentiating peptides (BPPs) and a bradykinin inhibitor were isolated from the Naja venom. 3-F neurotoxins, Kunitz/basic pancreatic trypsin inhibitor (BPTI)-type inhibitors and a natriuretic peptide were identified in the N. venom. The inhibiting activity of the peptides was confirmed in vitro with a selected array of proteases. Cytotoxin 1 (P01467) from the Naja venom might be involved in the disturbance of cellular processes by inhibiting the cell 20S-proteasome. A high degree of similarity between BPPs from elapid and viperid snake venoms was observed, suggesting that these molecules play a key role in snake venoms and also indicating that these peptides were recruited into the snake venom prior to the evolutionary divergence of the snakes. PMID:24590383
Full Text Available Elapid snake venom is a highly valuable, but till now mainly unexplored, source of pharmacologically important peptides. We analyzed the peptide fractions with molecular masses up to 10 kDa of two elapid snake venoms—that of the African cobra, N. m. mossambica (genus Naja, and the Peninsula tiger snake, N. scutatus, from Kangaroo Island (genus Notechis. A combination of chromatographic methods was used to isolate the peptides, which were characterized by combining complimentary mass spectrometric techniques. Comparative analysis of the peptide compositions of two venoms showed specificity at the genus level. Three-finger (3-F cytotoxins, bradykinin-potentiating peptides (BPPs and a bradykinin inhibitor were isolated from the Naja venom. 3-F neurotoxins, Kunitz/basic pancreatic trypsin inhibitor (BPTI-type inhibitors and a natriuretic peptide were identified in the N. venom. The inhibiting activity of the peptides was confirmed in vitro with a selected array of proteases. Cytotoxin 1 (P01467 from the Naja venom might be involved in the disturbance of cellular processes by inhibiting the cell 20S-proteasome. A high degree of similarity between BPPs from elapid and viperid snake venoms was observed, suggesting that these molecules play a key role in snake venoms and also indicating that these peptides were recruited into the snake venom prior to the evolutionary divergence of the snakes.
Kornhauser, Rachelle; Isbister, Geoffrey K; O'Leary, Margaret A; Mirtschin, Peter; Dunstan, Nathan; Hodgson, Wayne C
Cross-neutralisation has been demonstrated for haemorrhagic venoms including Echis spp. and Cerastes spp. and for Australia elapid procoagulant toxins. A previous study showed that commercial tiger snake antivenom (TSAV) was able to neutralise the systemic effects of the Egyptian cobra, Naja haje, in vivo but it is unclear if this was true cross-neutralisation. The aim of the current study was to determine whether TSAV can neutralise the in vitro neurotoxic effects of N. haje venom. Both Notechis scutatus (10 μg/ml) and N. haje (10 μg/ml) venoms caused inhibition of indirect (supramaximal V, 0.1 Hz, 0.2 msec.) twitches of the chick biventer cervicis nerve-muscle preparation with t(90) values (i.e. the time to produce 90% inhibition of the original twitch height) of 26 ± 1 min. (n = 4) and 36 ± 4 min.; (n = 4). This effect at 10 μg/ml was significantly attenuated by the prior addition of TSAV (5 U/ml). A comparison of the reverse-phase HPLC profiles of both venoms showed some similarities with peak elution times, and SDS-PAGE analysis elucidated comparable bands across both venoms. Further analysis using Western immunoblotting indicated TSAV was able to detect N. haje venom, and enzyme immunoassay showed that in-house biotinylated polyclonal monovalent N. scutatus antibodies were able to detect N. haje venom. These findings demonstrate cross-neutralisation between different and geographically separated snakes supporting potential immunological similarities in snake toxin groups for a large range of snakes. This provides more evidence that antivenoms could be developed against specific toxin groups to cover a large range of snakes. © 2012 The Authors Basic & Clinical Pharmacology & Toxicology © 2012 Nordic Pharmacological Society.
Shenoy, P A; Nipate, S S; Sonpetkar, J M; Salvi, N C; Waghmare, A B; Chaudhari, P D
Piper longum L. fruits have been traditionally used against snakebites in north-eastern and southern region of India. To examine the ability of ethanolic extract of fruits of Piper longum L., Piperaceae (PLE) and piperine, one of the main active principles of Piper longum, to inhibit the Russell's viper (Doboia russelii, Viperidae) snake venom activities. Anti-snake venom activities of ethanolic extract of fruits of Piper longum L. (Piperaceae) and piperine against Russell's viper venom was studied in embryonated fertile chicken eggs, mice and rats by using various models as follows: inhibition of venom lethal action, inhibition of venom haemorrhagic action (in vitro), inhibition of venom haemorrhagic action (in vivo), inhibition of venom necrotizing action, inhibition of venom defibrinogenating action, inhibition of venom induced paw edema, inhibition of venom induced mast cell degranulation, creatine kinase assay and assay for catalase activity. PLE was found to inhibit the venom induced haemorrhage in embryonated fertile chicken eggs. Administration of PLE and piperine significantly (p<0.01) inhibited venom induced lethality, haemorrhage, necrosis, defibrinogenation and inflammatory paw edema in mice in a dose dependent manner. PLE and piperine also significantly (p<0.01) reduced venom induced mast cell degranulation in rats. Venom induced decrease in catalase enzyme levels in mice kidney tissue and increase in creatine kinase enzyme levels in mice serum were significantly (p<0.01) reversed by administration of both PLE and piperine. PLE possesses good anti-snake venom properties and piperine is one of the compounds responsible for the effective venom neutralizing ability of the plant. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
B. M. A. Carvalho
Full Text Available Ophidian envenomation is an important health problem in Brazil and other South American countries. In folk medicine, especially in developing countries, several vegetal species are employed for the treatment of snakebites in communities that lack prompt access to serum therapy. However, the identification and characterization of the effects of several new plants or their isolated compounds, which are able to inhibit the activities of snake venom, are extremely important and such studies are imperative. Snake venom contains several organic and inorganic compounds; phospholipases A2 (PLA2s are one of the principal toxic components of venom. PLA2s display a wide variety of pharmacological activities, such as neurotoxicity, myotoxicity, cardiotoxicity, anticoagulant, hemorrhagic, and edema-inducing effects. PLA2 inhibition is of pharmacological and therapeutic interests as these enzymes are involved in several inflammatory diseases. This review describes the results of several studies of plant extracts and their isolated active principles, when used against crude snake venoms or their toxic fractions. Isolated inhibitors, such as steroids, terpenoids, and phenolic compounds, are able to inhibit PLA2s from different snake venoms. The design of specific inhibitors of PLA2s might help in the development of new pharmaceutical drugs, more specific antivenom, or even as alternative approaches for treating snakebites.
Shan, Lin-Lin; Gao, Jian-Fang; Zhang, Yan-Xia; Shen, Shan-Shan; He, Ying; Wang, Jin; Ma, Xiao-Mei; Ji, Xiang
Bungarus multicinctus (many-banded krait) and Naja atra (Chinese cobra) are widely distributed and medically important venomous snakes in China; however, their venom proteomic profiles have not been fully compared. Here, we fractionated crude venoms and analyzed them using a combination of proteomic techniques. Three-finger toxins (3-FTx) and phospholipase A2 (PLA2) were most abundant in both species, respectively accounting for 32.6% and 66.4% of total B. multicinctus venom, and 84.3% and 12.2% of total N. atra venom. Venoms from these two species contained one common protein family and six less abundant species-specific protein families. The proteomic profiles of B. multicinctus and N. atra venoms and analysis of toxicological activity in mice suggested that 3-FTx and PLA2 are the major contributors to clinical symptoms caused by envenomation. The venoms differed in enzymatic activity, likely the result of inter-specific variation in the amount of related venom components. Antivenomics assessment revealed that a small number of venom components (3-FTxs and PLA2s in B. multicinctus, and 3-FTxs in N. atra) could not be immunocaptured completely, suggesting that we should pay attention to enhancing the immune response of these components in designing commercial antivenoms for B. multicinctus and N. atra. The proteomic profiles of venoms from two medically important snake species - B. multicinctus and N. atra - have been explored. Quantitative and qualitative differences are evident in both venoms when proteomic profiles and transcriptomic results are compared; this is a reminder that combined approaches are needed to explore the precise composition of snake venom. Two protein families (3-FTx and PLA2) of high abundance in these snake venoms are major players in the biochemical and pharmacological effects of envenomation. Elucidation of the proteomic profiles of these snake venoms is helpful in understanding composition-function relationships and will facilitate the
Nawarak, Jiraporn; Phutrakul, Suree; Chen, Shui-Tein
This paper describes an efficient method of studying the glycoproteins found in snake venom. The glycosylation profiles of the Elapidae and Viperidae snake families were analyzed using FITC-labeled lectin glycoconjugates. The Con A-agarose affinity enrichment technique was used to fractionate glycoproteins from the N. naja kaouthia venom. The results revealed a large number of Con A binding glycoproteins, most of which have moderate to high molecular weights. To identify the proteins, the isolated glycoprotein fractions were subjected to two-dimensional electrophoresis and MALDI-TOF MS. Protein sequences were compared with published protein databases to determine for their biological functions.
Margres, Mark J; Aronow, Karalyn; Loyacano, Jacob; Rokyta, Darin R
Snake venom is shaped by the ecology and evolution of venomous species, and signals of positive selection in toxins have been consistently documented, reflecting the role of venoms as an ecologically critical phenotype. New World coral snakes (Elapidae) are represented by three genera and over 120 species and subspecies that are capable of causing significant human morbidity and mortality, yet coral-snake venom composition is poorly understood in comparison to that of Old World elapids. High-throughput sequencing is capable of identifying thousands of loci, while providing characterizations of expression patterns and the molecular evolutionary forces acting within the venom gland. We describe the de novo assembly and analysis of the venom-gland transcriptome of the eastern coral snake (Micrurus fulvius). We identified 1,950 nontoxin transcripts and 116 toxin transcripts. These transcripts accounted for 57.1% of the total reads, with toxins accounting for 45.8% of the total reads. Phospholipases A(2) and three-finger toxins dominated expression, accounting for 86.0% of the toxin reads. A total of 15 toxin families were identified, revealing venom complexity previously unknown from New World coral snakes. Toxins exhibited high levels of heterozygosity relative to nontoxins, and overdominance may favor gene duplication leading to the fixation of advantageous alleles. Phospholipase A(2) expression was uniformly distributed throughout the class while three-finger toxin expression was dominated by a handful of transcripts, and phylogenetic analyses indicate that toxin divergence may have occurred following speciation. Positive selection was detected in three of the four most diverse toxin classes, suggesting that venom diversification is driven by recurrent directional selection. We describe the most complete characterization of an elapid venom gland to date. Toxin gene duplication may be driven by heterozygote advantage, as the frequency of polymorphic toxin loci was
Smalligan, Roger; Cole, Judy; Brito, Narcissa; Laing, Gavin D; Mertz, Bruce L; Manock, Steven; Maudlin, Jeffrey; Quist, Brad; Holland, Gary; Nelson, Stephen; Lalloo, David G; Rivadeneira, Gonzalo; Barragan, Maria Elena; Dolley, Daniel; Eddleston, Michael; Warrell, David A; Theakston, R David G
Objective To compare the efficacy and safety of three polyspecific antivenoms for bites by pit vipers. Design Randomised double blind comparative trial of three antivenoms. Setting Shell, Pastaza, southeastern Ecuador. Participants 210 patients with incoagulable blood were recruited from 221 consecutive patients admitted with snake bite between January 1997 and December 2001. Intervention One of three antivenoms manufactured in Brazil, Colombia, and Ecuador, chosen for their preclinical potency against Ecuadorian venoms. Main outcome measures Permanent restoration of blood coagulability after 6 and 24 hours. Results The snakes responsible for the bites were identified in 187 cases: 109 patients (58%) were bitten by Bothrops atrox, 68 (36%) by B bilineatus, and 10 (5%) by B taeniatus, B brazili, or Lachesis muta. Eighty seven patients (41%) received Colombian antivenom, 82 (39%) received Brazilian antivenom, but only 41 (20%) received Ecuadorian antivenom because the supply was exhausted. Two patients died, and 10 developed local necrosis. All antivenoms achieved the primary end point of permanently restoring blood coagulability by 6 or 24 hours after the start of treatment in > 40% of patients. Colombian antivenom, however, was the most effective after initial doses of 20 ml (two vials), < 70 ml, and any initial dose at both 6 and 24 hours. An initial dose of 20 ml of Colombian antivenom permanently restored blood coagulability in 64% (46/72) of patients after 6 hours (P = 0.054 compared with the other two antivenoms) and an initial dose of < 70 ml was effective at 6 hours (65%, P = 0.045) and 24 hours (99%, P = 0.06). Early anaphylactoid reactions were common (53%, 73%, and 19%, respectively, for Brazilian, Colombian, and Ecuadorian antivenoms, P < 0.0001) but only three reactions were severe and none was fatal. Conclusions All three antivenoms can be recommended for the treatment of snakebites in this region, though the reactogenicity of Brazilian and Colombian
McCleary, Ryan J R; Sridharan, Sindhuja; Dunstan, Nathan L; Mirtschin, Peter J; Kini, R Manjunatha
Snake venom is a highly variable phenotypic character, and its variation and rapid evolution are important because of human health implications. Because much snake antivenom is produced from captive animals, understanding the effects of captivity on venom composition is important. Here, we have evaluated toxin profiles from six long-term (LT) captive and six recently wild-caught (RC) eastern brown snakes, Pseudonaja textilis, utilizing gel electrophoresis, HPLC-MS, and shotgun proteomics. We identified proteins belonging to the three-finger toxins, group C prothrombin activators, Kunitz-type serine protease inhibitors, and phospholipases A2, among others. Although crude venom HPLC analysis showed LT snakes to be higher in some small molecular weight toxins, presence/absence patterns showed no correlation with time in captivity. Shotgun proteomics indicated the presence of similar toxin families among individuals but with variation in protein species. Although no venom sample contained all the phospholipase A2 subunits that form the textilotoxin, all did contain both prothrombin activator subunits. This study indicates that captivity has limited effects on venom composition, that venom variation is high, and that venom composition may be correlated to geographic distribution. Through proteomic comparisons, we show that protein variation within LT and RC groups of snakes (Pseudonaja textilis) is high, thereby resulting in no discernible differences in venom composition between groups. We utilize complementary techniques to characterize the venom proteomes of 12 individual snakes from our study area, and indicate that individuals captured close to one another have more similar venom gel electrophoresis patterns than those captured at more distant locations. These data are important for understanding natural variation in and potential effects of captivity on venom composition. Copyright © 2016 Elsevier B.V. All rights reserved.
Li, Min; Fry, Bryan G; Kini, R Manjunatha
Accelerated evolution of toxins is a unique feature of venoms, with the toxins evolving via the birth-and-death mode of molecular evolution. The venoms of sea snakes, however, are remarkably simple in comparison to those of land snakes, which contain highly complex venoms. Aipysurus eydouxii (Marbled sea snake) is a particularly unique sea snake, feeding exclusively upon fish eggs. Secondary to this ecological change, the fangs have been lost and the venom glands greatly atrophied. We recently showed that the only neurotoxin (a three-finger toxin) gene found in the sea snake A. eydouxii has a dinucleotide deletion, resulting in the loss of neurotoxic activity. During these studies, we isolated and identified a number of cDNA clones encoding isozymes of phospholipase A(2) (PLA(2)) toxins from its venom gland. Sixteen unique PLA(2) clones were sequenced from the cDNA library and TA cloning of reverse transcription-polymerase chain reaction products. Phylogenetic analysis of these clones revealed that less diversification of the PLA(2) toxins has occurred in the A. eydouxii venom gland in comparison to equivalent terrestrial and other marine snakes. As there is no longer a positive selection pressure acting upon the venom, mutations have accumulated in the toxin-coding regions that would have otherwise had a deleterious effect upon the ability to use the venom for prey capture. Such mutations include substitutions of highly conserved residues; in one clone, the active site His(48) is replaced by Arg, and in two other clones, highly conserved cysteine residues are replaced. These mutations significantly affect the functional and structural properties of these PLA(2) enzymes, respectively. Thus, in A. eydouxii, the loss of the main neurotoxin is accompanied by a much slower rate of molecular evolution of the PLA(2) toxins as a consequence of the snake's shift in ecological niche. This is the first case of decelerated evolution of toxins in snake venom.
Snake venomics across genus Lachesis. Ontogenetic changes in the venom composition of Lachesis stenophrys and comparative proteomics of the venoms of adult Lachesis melanocephala and Lachesis acrochorda.
Madrigal, Marvin; Sanz, Libia; Flores-Díaz, Marietta; Sasa, Mahmood; Núñez, Vitelbina; Alape-Girón, Alberto; Calvete, Juan J
We report the proteomic analysis of ontogenetic changes in venom composition of the Central American bushmaster, Lachesis stenophrys, and the characterization of the venom proteomes of two congeneric pitvipers, Lachesis melanocephala (black-headed bushmaster) and Lachesis acrochorda (Chochoan bushmaster). Along with the previous characterization of the venom proteome of Lachesis muta muta (from Bolivia), our present outcome enables a comparative overview of the composition and distribution of the toxic proteins across genus Lachesis. Comparative venomics revealed the close kinship of Central American L. stenophrys and L. melanocephala and support the elevation of L. acrochorda to species status. Major ontogenetic changes in the toxin composition of L. stenophrys venom involves quantitative changes in the concentration of vasoactive peptides and serine proteinases, which steadily decrease from birth to adulthood, and age-dependent de novo biosynthesis of Gal-lectin and snake venom metalloproteinases (SVMPs). The net result is a shift from a bradykinin-potentiating and C-type natriuretic peptide (BPP/C-NP)-rich and serine proteinase-rich venom in newborns and 2-years-old juveniles to a (PI>PIII) SVMP-rich venom in adults. Notwithstanding minor qualitative and quantitative differences, the venom arsenals of L. melanocephala and L. acrochorda are broadly similar between themselves and also closely mirror those of adult L. stenophrys and L. muta venoms. The high conservation of the overall composition of Central and South American bushmaster venoms provides the ground for rationalizing the "Lachesis syndrome", characterized by vagal syntomatology, sensorial disorders, hematologic, and cardiovascular manifestations, documented in envenomings by different species of this wide-ranging genus. This finding let us predict that monospecific Lachesic antivenoms may exhibit paraspecificity against all congeneric species. Copyright © 2012 Elsevier B.V. All rights reserved.
Incio Ruiz, R; Incio Ruiz, L; Martínez-Vargas, A Z; Salas Arruz, M; Gutiérrez, J M
The lethal potencies (Median Lethal Dose) of the venoms of Peruvian snakes (Bothrops atrox, Bothrops barnetti, Bothrops pictus and Lachesis muta muta) were determined in mice by using intravenous and intraperitoneal routes of injection. In addition, the neutralizing ability of three antivenoms (bothropic polyvalent, bothropic bivalent and lachetic) was studied by preincubation-type experiments. B. pictus venom had the highest lethality by the intraperitoneal route whereas B. atrox venom had the highest lethality when tested by the intravenous route. The three antivenoms were effective in neutralizing lethality of the homologous venoms. Bivalent antivenom was more effective than polyvalent antivenom in the neutralization of B. pictus venom. On the basis of these findings, the use of bivalent bothropic antivenom is recommended in the Pacific coastal regions of Perú, whereas polyvalent bothropic antivenom is recommended in the oriental jungle regions of the country.
Estevao-Costa, Maria I; Gontijo, Silea S; Correia, Barbara L; Yarleque, Armando; Vivas-Ruiz, Dan; Rodrigues, Edith; Chávez-Olortegui, Carlos; Oliveira, Luciana S; Sanchez, Eladio F
Snakebite envenoming is a neglected public pathology, affecting especially rural communities or isolated areas of tropical and subtropical Latin American countries. The parenteral administration of antivenom is the mainstay and the only validated treatment of snake bite envenoming. Here, we assess the efficacy of polyspecific anti-Bothrops serum (α-BS) produced in the Instituto Nacional de Salud (INS, Peru) and at the Fundação Ezequiel Dias (FUNED, Brazil), to neutralize the main toxic activities induced by five medically-relevant venoms of: Bothrops atrox, B. barnetti, and B. pictus from Peru, and the Brazilian B. jararaca and B. leucurus, all of them inhabiting different geographical locations. Protein electrophoretic patterns of these venoms showed significant differences in composition, number and intensity of bands. Another goal was to evaluate the efficacy and safety of lyophilized α-BS developed at INS to neutralize the detrimental effects of these venoms using in vivo and in vitro assays. The availability of lyophilized α-BS has relevant significance in its distribution to distant rural communities where the access to antivenom in health facilities is more difficult. Despite the fact that different antigen mixtures were used for immunization during antivenom production, our data showed high toxin-neutralizing activity of α-BS raised against Bothrops venoms. Moreover, the antivenom cross-reacted even against venoms not included in the immunization mixture. Furthermore, we have evaluated the efficacy of both α-BS to neutralize key toxic compounds belonging to the predominant protein families of Bothrops snakes. Most significantly, both α-BS cross-specifically neutralized the main toxicological activities e.g. lethality and hemorrhage induced by these venoms. Thus, our data indicate that both α-BS are equally effective to treat snake bite victims inflicted by Bothrops snakes particularly B. atrox, responsible for the largest numbers of human
Yunusova, E S; Sadykov, E S; Sultanalieva, N M; Shkinev, A V
Ability of fractions of cobra's (Naja oxiana Eichwald) and copperhead snake's (Agkistrodon halys halys) venoms to hydrolyze fibrinogen/fibrin was studied. In cobra's snake a component with molecular mass of nearly 60 kDa was found to hydrolyze a-chain of fibrinogen but failed to hydrolyze casein/azocasein and fibrin. A fibrinogen-specific metalloproteinase, the enzyme was inhibited by EDTA. Cobra's venom reduced the mass of donor's fresh blood clots. The copperhead snake's venom and the fractions obtained by gel-filtration (HW-50) and ion exchange chromatography (DEAE-650) were found to hydrolyze casein/azocasein, a- and b-chains of fibrinogen/fibrin and donor's blood clots. The results from the study of the venom and proteolytically active fractions are the evidence for a thrombolytic potential in a copperhead snake's venom.
Venkata Krishna Pothukuchi
Full Text Available Snakebite is an important medical problem in India. Among their various manifestations, cerebral complications are uncommonly found in literature. Moreover, Ischemic stroke following snake bite is quite rare. Here we report a case series of two such cases that developed neurological manifestations following Russell’s viper bite. On computerized tomography (CT scan of brain; cerebral infarcts were revealed. Their likely mechanisms are discussed in present study which include disseminated intravascular coagulation, toxin induced vasculitis and endothelial damage.
Skejic, Jure; Steer, David L; Dunstan, Nathan; Hodgson, Wayne C
This study demonstrates a direct role of venom protein expression alteration in the evolution of snake venom toxicity. Avian skeletal muscle contractile response to exogenously administered acetylcholine is completely inhibited upon exposure to South Australian and largely preserved following exposure to Queensland eastern brown snake Pseudonaja textilis venom, indicating potent postsynaptic neurotoxicity of the former and lack thereof of the latter venom. Label-free quantitative proteomics reveals extremely large differences in the expression of postsynaptic three-finger α-neurotoxins in these venoms, explaining the difference in the muscle contractile response and suggesting that the type of toxicity induced by venom can be modified by altered expression of venom proteins. Furthermore, the onset of neuromuscular paralysis in the rat phrenic nerve-diaphragm preparation occurs sooner upon exposure to the venom (10 μg/mL) with high expression of α-neurotoxins than the venoms containing predominately presynaptic β-neurotoxins. The study also finds that the onset of rat plasma coagulation is faster following exposure to the venoms with higher expression of venom prothrombin activator subunits. This is the first quantitative proteomic study that uses extracted ion chromatogram peak areas (MS1 XIC) of distinct homologous tryptic peptides to directly show the differences in the expression of venom proteins.
Isotachophoretic and immunological analysis of venoms from sea snakes (Laticauda semifasciata) and brown recluse spiders (Loxosceles reclusa) of different morphology, locality, sex, and developmental stages.
Kent, C G; Tu, A T; Geren, C R
Sea snake venom: The venom compositions of sea snakes, Laticauda semifasciata, with different scale patterns were analyzed by isotachophoresis. The comparison showed quantitative rather than qualitative differences. Similarly, L. semifasciata venoms of Philippine and Japanese origins differed only in the quantity of certain proteins. Spider venom: 3. Loxosceles reclusa venom apparatus extract is rich in neutral and acidic proteins but contains relatively small quantities of basic proteins. Differences in venom apparatus extract composition between nymph and adult (male or female) were detected by isotachophoresis. The extracts of male and female venom apparatus were very similar. Extracts of venom apparatus of spiders collected in locations separated by 100 miles were the same.
Maduwage, Kalana P; Scorgie, Fiona E; Lincz, Lisa F; O'Leary, Margaret A; Isbister, Geoffrey K
Animal models are used to test toxic effects of snake venoms/toxins and the antivenom required to neutralise them. However, venoms that cause clinically relevant coagulopathy in humans may have differential effects in animals. We aimed to investigate the effect of different procoagulant snake venoms on various animal plasmas. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and D-dimer levels were measured in seven animal plasmas (human, rabbit, cat, guinea pig, pig, cow and rat). In vitro clotting times were then used to calculate the effective concentration (EC50) in each plasma for four snake venoms with different procoagulant toxins: Pseudonaja textilis, Daboia russelli, Echis carinatus and Calloselasma rhodostoma. Compared to human, PT and aPTT were similar for rat, rabbit and pig, but double for cat and cow, while guinea pig had similar aPTT but double PT. Fibrinogen and D-dimer levels were similar for all species. Human and rabbit plasmas had the lowest EC50 for P. textilis (0.1 and 0.4 μg/ml), D. russelli (0.4 and 0.1 μg/ml), E. carinatus (0.6 and 0.1 μg/ml) venoms respectively, while cat plasma had the lowest EC50 for C. rhodostoma (11 μg/ml) venom. Cow, rat, pig and guinea pig plasmas were highly resistant to all four venoms with EC50 10-fold that of human. Different animal plasmas have varying susceptibility to procoagulant venoms, and excepting rabbits, animal models are not appropriate to test procoagulant activity. In vitro assays on human plasma should instead be adopted for this purpose. Copyright © 2015 Elsevier Ltd. All rights reserved.
Expression pattern of three-finger toxin and phospholipase A2 genes in the venom glands of two sea snakes, Lapemis curtus and Acalyptophis peronii: comparison of evolution of these toxins in land snakes, sea kraits and sea snakes
Pahari, Susanta; Bickford, David; Fry, Bryan G; Kini, R Manjunatha
Background Snake venom composition varies widely both among closely related species and within the same species, based on ecological variables. In terrestrial snakes, such variation has been proposed to be due to snakes' diet. Land snakes target various prey species including insects (arthropods), lizards (reptiles), frogs and toads (amphibians), birds (aves), and rodents (mammals), whereas sea snakes target a single vertebrate class (fishes) and often specialize on specific types of fish. It is therefore interesting to examine the evolution of toxins in sea snake venoms compared to that of land snakes. Results Here we describe the expression of toxin genes in the venom glands of two sea snakes, Lapemis curtus (Spine-bellied Sea Snake) and Acalyptophis peronii (Horned Sea Snake), two members of a large adaptive radiation which occupy very different ecological niches. We constructed cDNA libraries from their venom glands and sequenced 214 and 192 clones, respectively. Our data show that despite their explosive evolutionary radiation, there is very little variability in the three-finger toxin (3FTx) as well as the phospholipase A2 (PLA2) enzymes, the two main constituents of Lapemis curtus and Acalyptophis peronii venom. To understand the evolutionary trends among land snakes, sea snakes and sea kraits, pairwise genetic distances (intraspecific and interspecific) of 3FTx and PLA2 sequences were calculated. Results show that these proteins appear to be highly conserved in sea snakes in contrast to land snakes or sea kraits, despite their extremely divergent and adaptive ecological radiation. Conclusion Based on these results, we suggest that streamlining in habitat and diet in sea snakes has possibly kept their toxin genes conserved, suggesting the idea that prey composition and diet breadth may contribute to the diversity and evolution of venom components. PMID:17900344
Carlos Roberto de Medeiros
Full Text Available Abstract INTRODUCTION Infrared imaging (IR is a noninvasive technique that quantifies body surface temperature, producing a digital color image. IR has been used to study diseases in which skin temperature can reflect the presence of inflammation. METHODS This was an observational pilot study of eight patients envenomed by snakes, spiders, and scorpions. All patients were examined using a thermal camera. RESULTS In all cases, we obtained infrared images that corroborated clinical findings indicating localized effects of venom, specifically inflammation. CONCLUSIONS IR has potential for use as a research, diagnostic, and monitoring tool for localized effects of animal venoms.
de Oliveira, Sayonara Ay More; Magalhães, Marta Regina; de Oliveira, Lilibete P; da Cunha, Luiz Carlos
The crude venom of the snake Crotalus durissus collilineatus (CDC) promotes neurological signs and symptoms in accidents involving humans and animals and the victims reports analgesia at the bite site, without tissue destruction. Studies shows that CDC has analgesic activity, among others. The crude venom is considered unsuitable for therapeutic purposes, with encouragement to the fractionation and purification of the same. Thus, the aim with CDC venom is: to perform fractionation by preparative HPLC; to test the antinociceptive activity of fractions and acute toxicity of active fractions. The CDC was fractionated on preparative HPLC-PDA (Oliveira et al., 2015) and the fractions were tested for their antinociceptive activity for writhing test by acetic acid (0.6%) in mice. For one of the fractions, which showed high analgesic effect both p.o. and i.p. routes, it evaluated the acute toxicity by the up and down method (OECD, 2001). In the fractionation by HPLC-PDA, CDC yielded 10 peaks (P1P10). SDS-PAGE showed that there was a good separation of components of the venom. All peaks were evaluated for their ability to reduce writhing, and the only one that apparently showed antinociceptive effect was Fr5 fraction (40 μg/kg). The Fr5 was able to reduce by 47% the number of contortions (i.p.) and 87% (p.o.), compared to control. The Fr5 fraction showed no morbidity and no mortality in the acute toxicity test (dose of 1000 μg/kg, p.o.); so it was not possible to estimate the LD50. According to the results, it can be stated that the venom and Fr5 of Crotalus durissus collilineatus snake of crotamine-negative type, may exhibit antinociceptive activity by suppressing nociception induced by acetic acid, suggesting it is related to effects on peripheral sites spinal and presents low acute toxicity values in experimental animals. Copyright © 2016 Elsevier Ltd. All rights reserved.
Liesener, A.; Perchuc, Anna-Maria; Schöni, Reto; Schebb, Nils Helge; Wilmer, Marianne; Karst, U.
An electrospray ionization/mass spectrometry (ESI/MS)-based assay for the determination of acetylcholinesterase (AChE)-inhibiting activity in snake venom was developed. It allows the direct monitoring of the natural AChE substrate acetylcholine (AC) and the respective product choline. The assay
Almeida, J R; Resende, L M; Watanabe, R K; Carregari, V C; Huancahuire-Vega, S; da S Caldeira, C A; Coutinho-Neto, A; Soares, A M; Vale, N; de C Gomes, P A; Marangoni, S; de A Calderon, L; Da Silva, S L
Snake venoms are natural sources of biologically active molecules that are able to act selectively and specifically on different cellular targets, modulating physiological functions. Thus, these mixtures, composed mainly of proteins and peptides, provide ample and challenging opportunities and a diversified molecular architecture to design and develop tools and agents of scientific and therapeutic interest. Among these components, peptides and small proteins play diverse roles in numerous physiological processes, exerting a wide range of pharmacological activities, such as antimicrobial, antihypertensive, analgesic, antitumor, analgesic, among others. The pharmaceutical and cosmetic industries have recognized the huge potential of these privileged frameworks and believe them to be a promising alternative to contemporary drugs. A number of natural or synthetic peptides from snake venoms have already found preclinical or clinical applications for the treatment of pain, hypertension, cardiovascular diseases and aging skin. A well-known example is captopril, whose natural peptide precursor was isolated from Bothrops jararaca snake venom, which is a peptide-based drug that inhibits the angiotensin-converting enzyme, producing an anti-hypertensive effect. The present review looks at the main peptides (natriuretic peptides, bradykinin-potentiating peptides and sarafotoxins) and low mass proteins (crotamine, disintegrins and three-Finger toxins) from snake venoms, as well as synthetic peptides inspired by them, describing their biochemical, structural and physiological features, as well as their applications as research tools and therapeutic agents. Copyright© Bentham Science Publishers; For any queries, please email at firstname.lastname@example.org.
Nielsen, Vance G; Bazzell, Charles M
A complication of defibrinogenation therapy with snake venom enzymes such as ancrod is hypofibrinogenemia associated bleeding secondary to no human-derived inhibitor being available to inactivate or diminish the activity of such enzymes. Of interest, ancrod contains a critical histidine residue without which enzymatic activity is inhibited, and carbon monoxide has been demonstrated to inhibit biomolecular function by interacting with histidine moieties in ion channels. We tested the hypothesis that exposure of three different snake venoms containing serine proteases with thrombin-like activity (which included ancrod) to carbon monoxide derived from carbon monoxide releasing molecule-2 would diminish their effects on plasmatic coagulation as assessed by thrombelastography. In the case of the Malayan pit viper and Eastern diamondback rattlesnake venoms, carbon monoxide diminished the effects of thrombin-like activity. In contrast, timber rattlesnake venom demonstrated enhancement of "thrombin-generating" activity with simultaneous loss of thrombin-like activity in response to carbon monoxide exposure. These findings may serve as the rational basis for not just continuing to investigate the potential of snake venom enzymes as clinical defibrinogenating agents, but to also to assess the potential to stop such agents from becoming a catalytic "runaway train" by judicious application of a biochemical "brake" such as carbon monoxide.
Growth inhibition of Trypanosoma cruzi and Leishmania donovani infantum by different snake venoms: preliminary identification of proteins from Cerastes cerastes venom which interact with the parasites.
Fernandez-Gomez, R; Zerrouk, H; Sebti, F; Loyens, M; Benslimane, A; Ouaissi, M A
Venom from three different snake species was tested in vitro against the protozoan parasites Trypanosoma cruzi and Leishmania donovani infantum. Two of them, Cerastes cerastes and Naja haje, exerted a significant growth inhibition of T. cruzi and L. d. infantum parasites. Heating of the venoms abolished their activity, suggesting that the active factors are thermolabile. Incubation of parasites with 125I-labelled C. cerastes venom proteins allowed preliminary identification of components which interact preferentially with the pathogens.
Peixoto, Pedro S.; Bernardoni, Juliana L.; Oliveira, Sâmella S.; Portes-Junior, José Antonio; Mourão, Rosa Helena V.; Lima-dos-Santos, Isa; Sano-Martins, Ida S.; Chalkidis, Hipócrates M.; Valente, Richard H.; Moura-da-Silva, Ana M.
In Latin America, Bothrops snakes account for most snake bites in humans, and the recommended treatment is administration of multispecific Bothrops antivenom (SAB – soro antibotrópico). However, Bothrops snakes are very diverse with regard to their venom composition, which raises the issue of which venoms should be used as immunizing antigens for the production of pan-specific Bothrops antivenoms. In this study, we simultaneously compared the composition and reactivity with SAB of venoms collected from six species of snakes, distributed in pairs from three distinct phylogenetic clades: Bothrops, Bothropoides and Rhinocerophis. We also evaluated the neutralization of Bothrops atrox venom, which is the species responsible for most snake bites in the Amazon region, but not included in the immunization antigen mixture used to produce SAB. Using mass spectrometric and chromatographic approaches, we observed a lack of similarity in protein composition between the venoms from closely related snakes and a high similarity between the venoms of phylogenetically more distant snakes, suggesting little connection between taxonomic position and venom composition. P-III snake venom metalloproteinases (SVMPs) are the most antigenic toxins in the venoms of snakes from the Bothrops complex, whereas class P-I SVMPs, snake venom serine proteinases and phospholipases A2 reacted with antibodies in lower levels. Low molecular size toxins, such as disintegrins and bradykinin-potentiating peptides, were poorly antigenic. Toxins from the same protein family showed antigenic cross-reactivity among venoms from different species; SAB was efficient in neutralizing the B. atrox venom major toxins. Thus, we suggest that it is possible to obtain pan-specific effective antivenoms for Bothrops envenomations through immunization with venoms from only a few species of snakes, if these venoms contain protein classes that are representative of all species to which the antivenom is targeted. PMID
Jorge da Silva, N; Aird, S D
Toxicities of crude venoms from 49 coral snake (Micrurus sp.) populations, representing 15 nominal taxa, were examined in both laboratory mice and in native prey animals and compared with data gathered from two non-micrurine elapids and a crotalid, which served as outgroups. These venoms were further compared on the basis of 23 enzymatic activities. Both toxicities and enzymatic activities were analyzed with respect to natural prey preferences, as determined from stomach content analyses and literature reports. Venoms of nearly all Micrurus for which prey preferences are known, are more toxic to natural prey than to non-prey species. Except for amphisbaenians, prey are more susceptible to venoms of Micrurus that feed upon them, than to venoms of those that eat other organisms. All venoms were more toxic i.v.>i.p.>i.m. Route-specific differences in toxicity are generally greatest for preferred prey species. Cluster analyses of venom enzymatic activities resulted in five clusters, with the fish-eating M. surinamensis more distant from other Micrurus than even the crotalid, Bothrops moojeni. Ophiophagous and amphisbaenian-eating Micrurus formed two close subclusters, one allied to the outgroup species Naja naja and the other to the fossorial, ophiophagous Bungarus multicinctus. Prey preference is shown to be the most important determinant of venom composition in Micrurus.
Eisenberg, Tobias; Poignant, Simon; Jouan, Youenn; Fawzy, Ahmad; Nicklas, Werner; Ewers, Christa; Mereghetti, Laurent; Guillon, Antoine
We report acute tetraplegia caused by rat bite fever in a 59-year old man (snake keeper) and transmission of Streptobacillus moniliformis. We found an identical characteristic bacterial pattern in rat and human samples, which validated genotyping-based evidence for infection with the same strain, and identified diagnostic difficulties concerning infection with this microorganism.
Snake bite remains a public health hazard in tropical countries. Taraba State with a high Fulani population has one of the highest incidences in the country. The Fulani herdsmen are more at risk because of their agropastoralist lifestyle. Their village settlement positions make it more difficult for them to assess antiserum, the ...
Snake-bite can be both life and limb threatening, especially when there is envenomation. Early intervention in a fairly equipped health facility can go a long way in preventing the morbidity and mortality that can result from delay in initiating treatment. In this paper we report two cases of snakebite to the lower limbs in children ...
Freitas-de-Sousa, L A; Amazonas, D R; Sousa, L F; Sant'Anna, S S; Nishiyama, M Y; Serrano, S M T; Junqueira-de-Azevedo, I L M; Chalkidis, H M; Moura-da-Silva, A M; Mourão, R H V
Comparisons between venoms from snakes kept under captivity or collected at the natural environment are of fundamental importance in order to obtain effective antivenoms to treat human victims of snakebites. In this study, we compared composition and biological activities of Bothrops atrox venom from snakes collected at Tapajós National Forest (Pará State, Brazil) or maintained for more than 10 years under captivity at Instituto Butantan herpetarium after have been collected mostly at Maranhão State, Brazil. Venoms from captive or wild snakes were similar except for small quantitative differences detected in peaks correspondent to phospholipases A2 (PLA2), snake venom metalloproteinases (SVMP) class PI and serine proteinases (SVSP), which did not correlate with fibrinolytic and coagulant activities (induced by PI-SVMPs and SVSPs). In both pools, the major toxic component corresponded to PIII-SVMPs, which were isolated and characterized. The characterization by mass spectrometry of both samples identified peptides that matched with a single PIII-SVMP cDNA characterized by transcriptomics, named Batroxrhagin. Sequence alignments show a strong similarity between Batroxrhagin and Jararhagin (96%). Batroxrhagin samples isolated from venoms of wild or captive snakes were not pro-coagulant, but inhibited collagen-induced platelet-aggregation, and induced hemorrhage and fibrin lysis with similar doses. Results suggest that in spite of environmental differences, venom variability was detected only among the less abundant components. In opposition, the most abundant toxin, which is a PIII-SVMP related to the key effects of the venom, is structurally conserved in the venoms. This observation is relevant for explaining the efficacy of antivenoms produced with venoms from captive snakes in human accidents inflicted at distinct natural environments. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.
Full Text Available The complete sequence characterization of snake venom proteins by mass spectrometry is rather challenging due to the presence of multiple isoforms from different protein families. In the present study, we investigated the tryptic digest of the venom of the viperid snake Sistrurus catenatus edwardsii by a combined approach of liquid chromatography coupled to either electrospray (online or MALDI (offline mass spectrometry. These different ionization techniques proved to be complementary allowing the identification a great variety of isoforms of diverse snake venom protein families, as evidenced by the detection of the corresponding unique peptides. For example, ten out of eleven predicted isoforms of serine proteinases of the venom of S. c. edwardsii were distinguished using this approach. Moreover, snake venom protein families not encountered in a previous transcriptome study of the venom gland of this snake were identified. In essence, our results support the notion that complementary ionization techniques of mass spectrometry allow for the detection of even subtle sequence differences of snake venom proteins, which is fundamental for future structure-function relationship and possible drug design studies.
Chapeaurouge, Alex; Reza, Md Abu; Mackessy, Stephen P.; Carvalho, Paulo C.; Valente, Richard H.; Teixeira-Ferreira, André; Perales, Jonas; Lin, Qingsong; Kini, R. Manjunatha
The complete sequence characterization of snake venom proteins by mass spectrometry is rather challenging due to the presence of multiple isoforms from different protein families. In the present study, we investigated the tryptic digest of the venom of the viperid snake Sistrurus catenatus edwardsii by a combined approach of liquid chromatography coupled to either electrospray (online) or MALDI (offline) mass spectrometry. These different ionization techniques proved to be complementary allowing the identification a great variety of isoforms of diverse snake venom protein families, as evidenced by the detection of the corresponding unique peptides. For example, ten out of eleven predicted isoforms of serine proteinases of the venom of S. c. edwardsii were distinguished using this approach. Moreover, snake venom protein families not encountered in a previous transcriptome study of the venom gland of this snake were identified. In essence, our results support the notion that complementary ionization techniques of mass spectrometry allow for the detection of even subtle sequence differences of snake venom proteins, which is fundamental for future structure-function relationship and possible drug design studies. PMID:25955844
Chacón, Danilo; Rodríguez, Santos; Arias, Jazmín; Solano, Gabriela; Bonilla, Fabián; Gómez, Aarón
American Elapid snakes (Coral Snakes) comprise the genera Leptomicrurus, Micruroides and Micrurus, which form a vast taxonomic assembly of 330 species distributed from the South of United States to the southern region of South America. In order to obtain venom for animal immunizations aimed at antivenom production, Coral Snakes must be kept in captivity and submitted periodically to venom extraction procedures. Thus, to maintain a snake colony in good health for this purpose, a complete alternative diet utilizing an easily obtained prey animal is desirable. The development of a diet based on fish is compared to the wild diet based on colubrid snakes, and assessed in terms of gain in body weight rate (g/week), longevity (weeks), venom yield (mg/individual), venom median lethal dose (LD₅₀) and venom chromatographic profiles. The animals fed with the fish-based diet gained more weight, lived longer, and produced similar amount of venom whose biological and biochemical characteristics were similar to those of venom collected from specimens fed with the wild diet. This fish-based diet appears to be suitable (and preferable to the wild diet) to supply the nutritional requirements of a Micrurus nigrocinctus snake collection for the production of antivenom. Copyright © 2012 Elsevier Ltd. All rights reserved.
Al-Asmari, Abdulrahman Khazim; Riyasdeen, Anvarbatcha; Al-Shahrani, Mohammad Hamed; Islam, Mozaffarul
Snake venom possesses various kinds of proteins and neurotoxic polypeptides, which can negatively interfere with the neurotransmitter signaling cascade. This phenomenon occurs mainly due to the blocking of ion channels in the body system. Envenomation prevents or severely interrupts nerve impulses from being transmitted, inhibition of adenosine triphosphate synthesis, and proper functioning of the cardiac muscles. However, some beneficial properties of venoms have also been reported. The aim of this study was to examine the snake venom as an anticancer agent due to its inhibitory effects on cancer progression such as cell motility, cell invasion, and colony formation. In this study, the effect of venoms on phenotypic changes and the change on molecular level in colorectal and breast cancer cell lines were examined. A reduction of 60%–90% in cell motility, colony formation, and cell invasion was observed when these cell lines were treated with different concentrations of snake venom. In addition, the increase in oxidative stress that results in an increase in the number of apoptotic cancer cells was significantly higher in the venom-treated cell lines. Further analysis showed that there was a decrease in the expression of pro-inflammatory cytokines and signaling proteins, strongly suggesting a promising role for snake venom against breast and colorectal cancer cell progression. In conclusion, the snake venoms used in this study showed significant anticancer properties against colorectal and breast cancer cell lines. PMID:27799796
Sanjeev Vasantrao Chincholikar
Full Text Available Background: Cause of ‘unacceptable incidence’ of snake bite fatalities is that people try out all kinds of ‘bizarre remedies’ initially. Objectives: To study the knowledge about the types of snakes and their identification and to ascertain the knowledge about first aid. Methods: A cross sectional study was carried out in 10 adopted villages under Rural Health Training Centre, from July 2011 to June 2012. Out of 2272 households, a proportionate sample was selected and one representative from each household was further selected at random. Results: The awareness about first aid measures was less in all subjects but the knowledge about symptoms of snake bite was higher in majority of subjects. It was observed that knowledge about types of snakes was significantly higher in 12-20 years of age group (p <0.05. Out of 49 survived cases of total 68 cases, 8 cases were given wrong first aid. Use of mantriks, sucking of blood was practiced in few cases. In most of the cases the nearest health facility is not in a reachable distance, taking more than 30 minutes to reach and no transport facility is available to reach nearest health centre. Hence, in order to prevent untimely death, there is a need to provide knowledge regarding first aid treatment of snake bite to the villagers.
Pla, Davinia; Sanz, Libia; Whiteley, Gareth; Wagstaff, Simon C; Harrison, Robert A; Casewell, Nicholas R; Calvete, Juan J
Non-front-fanged colubroid snakes comprise about two-thirds of extant ophidian species. The medical significance of the majority of these snakes is unknown, but at least five species have caused life-threatening or fatal human envenomings. However, the venoms of only a small number of species have been explored. A combined venomic and venom gland transcriptomic approach was employed to characterise of venom of Dispholidus typus (boomslang), the snake that caused the tragic death of Professor Karl Patterson Schmidt. The ability of CroFab™ antivenom to immunocapture boomslang venom proteins was investigated using antivenomics. Transcriptomic-assisted proteomic analysis identified venom proteins belonging to seven protein families: three-finger toxin (3FTx); phospholipase A2 (PLA2); cysteine-rich secretory proteins (CRISP); snake venom (SV) serine proteinase (SP); C-type lectin-like (CTL); SV metalloproteinases (SVMPs); and disintegrin-like/cysteine-rich (DC) proteolytic fragments. CroFab™ antivenom efficiently immunodepleted some boomslang SVMPs. The present work is the first to address the overall proteomic profile of D. typus venom. This study allowed us to correlate the toxin composition with the toxic activities of the venom. The antivenomic analysis suggested that the antivenom available at the time of the unfortunate accident could have exhibited at least some immunoreactivity against the boomslang SVMPs responsible for the disseminated intravascular coagulation syndrome that caused K.P. Schmidt's fatal outcome. This study may stimulate further research on other non-front-fanged colubroid snake venoms capable of causing life-threatening envenomings to humans, which in turn should contribute to prevent fatal human accidents, such as that unfortunately suffered by K.P. Schmidt. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
Serafim, Francine G; Reali, Marielga; Cruz-Höfling, Maria Alice; Fontana, Marcos D
The venoms of coral snakes (mainly Micrurus species) have pre- and/or postsynaptic actions, but only a few of these have been studied in detail. We have investigated the effects of Micrurus dumerilii carinicauda coral snake venom on neurotransmission in rat isolated phrenic nerve-diaphragm muscle and chick biventer cervicis preparations stimulated directly or indirectly. M. d. carinicauda venom (5 or 10 microg/ml) produced neuromuscular blockade in rat (85-90% in 291.8+/-7.3 min and 108.3+/-13.8, respectively; n=5) and avian (95.0+/-2.0 min; 5 microg/ml, n=5) preparations. Neostigmine (5.8 microM) and 3,4-diaminopyridine (230 microM) partially reversed the venom-induced neuromuscular blockade in rat nerve-muscle preparations. In neither preparation did the venom depress the twitch response elicited by direct muscle stimulation. The contractures induced by acetylcholine in chick preparations were inhibited by the venom (95-100%; n=4; p<0.05). In rat preparations, the venom produced a progressive decrease in the amplitude of miniature end-plate potentials (m.e.p.ps control frequency=69.3+/-5.0/min and control amplitude=0.4+/-0.2 mV) until these were abolished. Neostigmine (5.8 microM) and 3,4-diaminopyridine (230 microM) partially antagonized this blockade of m.e.p.ps. The resting membrane potential was not altered with the venom (10 microg/ml). M. d. carinicauda venom produced dose-dependent morphological changes in indirectly stimulated mammal preparations. Twenty-five per cent of muscle fibers were affected by a venom concentration of 5 microg/ml, whilst 60.7% were damaged by 10 microg of venom/ml. In biventer cervicis preparations, the morphological changes were slower in onset and were generally characterized by undulating fibers and, to a lesser extent, by zones of disintegrating myofibrils. A venom concentration of 5 microg/ml damaged 52.2% of the fibers. These findings indicate that M. d. carinicauda venom has neurotoxic and myotoxic effects and that the
Full Text Available Snakebite envenomations cause severe local tissue necrosis and the venom metalloproteinases are thought to be the key toxins involved. In this study, the ethanolic extract from seed kernels of Thai mango (Mangifera indica L. cv. ‘Fahlun’ (Anacardiaceae and its major phenolic principle (pentagalloylglucopyranose exhibited potent and dose−dependent inhibitory effects on the caseinolytic and fibrinogenolytic activities of Malayan pit viper and Thai cobra venoms in in vitro tests. molecular docking studies revealed that the binding orientations of the phenolic principles were in the binding pockets of snake venom metalloproteinases (SVMPs. The phenolic principles could form hydrogen bonds with the three histidine residues in the conserved zinc−binding motif and could chelate the Zn2+ atom of the SVMPs, which could potentially result in inhibition of the venom enzymatic activities and thereby inhibit tissue necrosis.
Pithayanukul, Pimolpan; Leanpolchareanchai, Jiraporn; Saparpakorn, Patchreenart
Snakebite envenomations cause severe local tissue necrosis and the venom metalloproteinases are thought to be the key toxins involved. In this study, the ethanolic extract from seed kernels of Thai mango (Mangifera indica L. cv. 'Fahlun') (Anacardiaceae) and its major phenolic principle (pentagalloylglucopyranose) exhibited potent and dose-dependent inhibitory effects on the caseinolytic and fibrinogenolytic activities of Malayan pit viper and Thai cobra venoms in in vitro tests. molecular docking studies revealed that the binding orientations of the phenolic principles were in the binding pockets of snake venom metalloproteinases (SVMPs). The phenolic principles could form hydrogen bonds with the three histidine residues in the conserved zinc-binding motif and could chelate the Zn(2+) atom of the SVMPs, which could potentially result in inhibition of the venom enzymatic activities and thereby inhibit tissue necrosis.
Ching, Ana T C; Paes Leme, Adriana F; Zelanis, André; Rocha, Marisa M T; Furtado, Maria de Fátima D; Silva, Débora Andrade; Trugilho, Monique R O; da Rocha, Surza L G; Perales, Jonas; Ho, Paulo L; Serrano, Solange M T; Junqueira-de-Azevedo, Inácio L M
Rear-fanged and aglyphous snakes are usually considered not dangerous to humans because of their limited capacity of injecting venom. Therefore, only a few studies have been dedicated to characterizing the venom of the largest parcel of snake fauna. Here, we investigated the venom proteome of the rear-fanged snake Thamnodynastes strigatus , in combination with a transcriptomic evaluation of the venom gland. About 60% of all transcripts code for putative venom components. A striking finding is that the most abundant type of transcript (∼47%) and also the major protein type in the venom correspond to a new kind of matrix metalloproteinase (MMP) that is unrelated to the classical snake venom metalloproteinases found in all snake families. These enzymes were recently suggested as possible venom components, and we show here that they are proteolytically active and probably recruited to venom from a MMP-9 ancestor. Other unusual proteins were suggested to be venom components: a protein related to lactadherin and an EGF repeat-containing transcript. Despite these unusual molecules, seven toxin classes commonly found in typical venomous snakes are also present in the venom. These results support the evidence that the arsenals of these snakes are very diverse and harbor new types of biologically important molecules.
Akani, Godfrey C; Ebere, Nwabueze; Franco, Daniel; Eniang, Edem A; Petrozzi, Fabio; Politano, Edoardo; Luiselli, Luca
Abstract Background Venomous snakes are among the most serious health hazards for rural people in tropical regions of the world. Herein we compare the monthly activity patterns of eight venomous snake species (Elapidae and Viperidae) with those of rural people in the Niger Delta area of southern Nigeria, in order to identify the periods of highest potential risk for persons, and the human group actually at greater risk of snakebite. Results We documented that above-ground activity of all veno...
Lane, J; O'Leary, M A; Isbister, G K
The coagulant effects of Australasian black snakes (Pseudechis spp.) are poorly understood and differ to the procoagulant venoms of most dangerous snakes in Australia. This study aimed to investigate in vitro coagulant effects of Pseudechis venoms and the efficacy of commercial black snake antivenom (BlSAV), tiger snake antivenom (TSAV) and specific rabbit anti-snake IgG to neutralise these effects. Using a turbidimetric assay, all six Pseudechis venoms had anticoagulant activity, as well as phospholipase A(2) (PLA(2)) activity. Inhibition of PLA(2) activity removed anticoagulant effects of the venoms. Pseudechis porphyriacus was unique and had procoagulant activity independent of PLA2 activity. Both BlSAV and TSAV completely inhibited the coagulant and PLA2 activity of all Pseudechis venoms. PLA2 activity was also inhibited completely by p-Bromophenacyl bromide (pBPB) and partially by specific anti-N. scutatus IgG antibodies. Anti-N. scutatus IgG also completely inhibited anticoagulant activity of Pseudechis venom. All Pseudechis venoms showed immunological cross reactivity with specific anti-snake IgG antibodies to P. porphyriacus, Pseudechis australis and Notechis scutatus. Pseudechis venoms have in vitro anticoagulant activity that appears to be attributable to PLA(2) activity. Both antivenoms inhibited anticoagulant and PLA(2) activity at concentrations below those occurring in patients treated with one vial of antivenom. There was cross-neutralisation of Pseudechis venoms and N. scutatus antibodies that might be attributable to immunological similarities between the venoms. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.
Hill, R E; Mackessy, S P
The composition of rear-fanged colubrid snake venoms is largely unknown due primarily to the difficulty involved in venom collection. Several different methods have been used to maximize the yield of Duvernoy's secretions. The method proposed by Rosenberg in 1992, which includes the use of ketamine hydrochloride anesthetic and pilocarpine to induce Duvernoy's glands secretion, was used in the present study to collect venom from eight species of colubrids. Protein concentrations, using a dye-binding microassay technique, were determined for the venoms collected. Average protein concentrations ranged from 49.8 to 96.4%. Most yields (dry weight/snake) obtained from specimens in this study were significantly greater than yields previously reported. There was a wide range of effects that occurred due to the ketamine injections; however, all snakes recovered from the effects of the ketamine hydrochloride/pilocarpine with no apparent ill effects. Recommended doses of ketamine hydrochloride have thus been adjusted, depending on previous reactions to the drug. The use of ketamine/pilocarpine in the collection of Duvernoy's secretion has proven to be highly effective in increasing yields. Some caution should be observed when administering ketamine to various species of colubrids, as effects do not necessarily scale to body mass.
Lincz, Lisa F; Scorgie, Fiona E; Johnston, Christopher I; O'Leary, Margaret; Prasad, Ritam; Seldon, Michael; Favaloro, Emmanuel; Isbister, Geoffrey K
This study aimed to determine the relative sensitivity of activated partial thromboplastin time (aPTT) reagents to the anticoagulant effects of phospholipases in mulga snake (Pseudechis australis) venom.Twenty-one haematology laboratories participating in the Royal College of Pathologists of Australasia Quality Assurance Programs were sent human plasma samples spiked with mulga venom (n=25 total results). Results for 17 patients with mulga snake envenoming were available through the Australian Snakebite Project.Only 12 of 25 venom spiked samples returned an abnormally prolonged aPTT. Tests performed with Dade Actin FS (n=7) did not identify any of the spiked samples as abnormal. Although clotting times were significantly prolonged using the lupus anticoagulant sensitive Actin FSL (n=5, p=0.043), only one was reported as abnormal. Only laboratories using TriniCLOT aPTT S (n=6), HemosIL APTT SP (n=2) and Stago PTT-A (n=1) consistently recorded the spiked sample as being above the upper normal reference interval. Abnormally prolonged aPTTs were recorded for four of eight patients whose tests were performed with Actin FSL, five of eight patients with TriniCLOT aPTT HS, and three of three patients using TriniCLOT aPTT S.We conclude that some reagents used for routine aPTT testing are relatively insensitive to the anticoagulant effects of mulga snake venom. Tests performed with these reagents should be interpreted with caution.
Ramazanova, Anna S; Starkov, Vladislav G; Osipov, Alexey V; Ziganshin, Rustam H; Filkin, Sergey Yu; Tsetlin, Victor I; Utkin, Yuri N
Cysteine-rich proteins found in animal venoms (CRISP-Vs) are members of a large family of cysteine-rich secretory proteins (CRISPs). CRISP-Vs acting on different ion channels were found in venoms or mRNA (cDNA) encoding CRISP-Vs were cloned from snakes of three main families (Elapidae, Colubridae and Viperidae). About thirty snake CRISP-Vs were sequenced so far, however no complete sequence for CRISP-V from Viperinae subfamily was reported. We have cloned and sequenced for the first time cDNAs encoding CRISP-Vs from Vipera nikolskii and Vipera berus vipers (Viperinae). The deduced mature CRISP-V amino acid sequences consist of 220 amino acid residues. Phylogenetic analysis showed that viper proteins are closely related to those of Crotalinae snakes. The presence of CRISP-V in the V. berus venom was revealed using a combination of gel-filtration chromatography, electrophoresis and MALDI mass spectrometry. The finding of the putative channel blocker in viper venom may indicate its action on prey nervous system.
Lynch Vincent J
Full Text Available Abstract Background Gene duplication followed by functional divergence has long been hypothesized to be the main source of molecular novelty. Convincing examples of neofunctionalization, however, remain rare. Snake venom phospholipase A2 genes are members of large multigene families with many diverse functions, thus they are excellent models to study the emergence of novel functions after gene duplications. Results Here, I show that positive Darwinian selection and neofunctionalization is common in snake venom phospholipase A2 genes. The pattern of gene duplication and positive selection indicates that adaptive molecular evolution occurs immediately after duplication events as novel functions emerge and continues as gene families diversify and are refined. Surprisingly, adaptive evolution of group-I phospholipases in elapids is also associated with speciation events, suggesting adaptation of the phospholipase arsenal to novel prey species after niche shifts. Mapping the location of sites under positive selection onto the crystal structure of phospholipase A2 identified regions evolving under diversifying selection are located on the molecular surface and are likely protein-protein interactions sites essential for toxin functions. Conclusion These data show that increases in genomic complexity (through gene duplications can lead to phenotypic complexity (venom composition and that positive Darwinian selection is a common evolutionary force in snake venoms. Finally, regions identified under selection on the surface of phospholipase A2 enzymes are potential candidate sites for structure based antivenin design.
Lynch, Vincent J
Gene duplication followed by functional divergence has long been hypothesized to be the main source of molecular novelty. Convincing examples of neofunctionalization, however, remain rare. Snake venom phospholipase A2 genes are members of large multigene families with many diverse functions, thus they are excellent models to study the emergence of novel functions after gene duplications. Here, I show that positive Darwinian selection and neofunctionalization is common in snake venom phospholipase A2 genes. The pattern of gene duplication and positive selection indicates that adaptive molecular evolution occurs immediately after duplication events as novel functions emerge and continues as gene families diversify and are refined. Surprisingly, adaptive evolution of group-I phospholipases in elapids is also associated with speciation events, suggesting adaptation of the phospholipase arsenal to novel prey species after niche shifts. Mapping the location of sites under positive selection onto the crystal structure of phospholipase A2 identified regions evolving under diversifying selection are located on the molecular surface and are likely protein-protein interactions sites essential for toxin functions. These data show that increases in genomic complexity (through gene duplications) can lead to phenotypic complexity (venom composition) and that positive Darwinian selection is a common evolutionary force in snake venoms. Finally, regions identified under selection on the surface of phospholipase A2 enzymes are potential candidate sites for structure based antivenin design.
Fernández, Julián; Alape-Girón, Alberto; Angulo, Yamileth; Sanz, Libia; Gutiérrez, José María; Calvete, Juan J; Lomonte, Bruno
The proteome of the venom of Micrurus nigrocinctus (Central American coral snake) was analyzed by a "venomics" approach. Nearly 50 venom peaks were resolved by RP-HPLC, revealing a complex protein composition. Comparative analyses of venoms from individual specimens revealed that such complexity is an intrinsic feature of this species, rather than the sum of variable individual patterns of simpler composition. Proteins related to eight distinct families were identified by MS/MS de novo peptide sequencing or N-terminal sequencing: phospholipase A(2) (PLA(2)), three-finger toxin (3FTx), l-amino acid oxidase, C-type lectin/lectin-like, metalloproteinase, serine proteinase, ohanin, and nucleotidase. PLA(2)s and 3FTxs are predominant, representing 48 and 38% of the venom proteins, respectively. Within 3FTxs, several isoforms of short-chain α-neurotoxins as well as muscarinic-like toxins and proteins with similarity to long-chain κ-2 bungarotoxin were identified. PLA(2)s are also highly diverse, and a toxicity screening showed that they mainly exert myotoxicity, although some are lethal and may contribute to the known presynaptic neurotoxicity of this venom. An antivenomic characterization of a therapeutic monospecific M. nigrocinctus equine antivenom revealed differences in immunorecognition of venom proteins that correlate with their molecular mass, with the weakest recognition observed toward 3FTxs.
Isabela Nascimento Canhas
Full Text Available Toxins and venoms produced by living organisms have exhibited a variety of biological activities against microorganisms. In this study, we tested seven snake venoms from the family Viperidae for antibacterial activity and the activities of reversal of antibiotic resistance and inhibition of biofilm formation against 22 clinical isolates of Staphylococcus aureus. Bothrops moojeni venom exhibited anti staphylococcal activity with the lowest mean value of minimum inhibitory concentration (MIC. Moreover, reversal of antibiotic resistance was observed for combinations of B. moojeni venom (½ x MIC and norfloxacin or ampicillin (both ½ x MIC for 86.4% and 50% of the isolates, respectively. B. moojeni venom alone at ½ MIC inhibited 90% of biofilm formation, whereas in combination with ciprofloxacin, both at ½ MIC, a reduction on the NorA efflux pump activity was observed. The detection of in vitro mutants colonies of S. aureus resistant to B. moojeni venom was low and they did not survive. A phospholipase A2 was purified from the venom of B. moojeni and displayed anti-staphylococcal activity when tested alone or in combination with ciprofloxacin. The results presented here will contribute to the search for new antimicrobial agents against resistant S. aureus.
Tashima, Alexandre K.; Zelanis, André; Kitano, Eduardo S.; Ianzer, Danielle; Melo, Robson L.; Rioli, Vanessa; Sant'anna, Sávio S.; Schenberg, Ana C. G.; Camargo, Antônio C. M.; Serrano, Solange M. T.
Snake venom proteomes/peptidomes are highly complex and maintenance of their integrity within the gland lumen is crucial for the expression of toxin activities. There has been considerable progress in the field of venom proteomics, however, peptidomics does not progress as fast, because of the lack of comprehensive venom sequence databases for analysis of MS data. Therefore, in many cases venom peptides have to be sequenced manually by MS/MS analysis or Edman degradation. This is critical for rare snake species, as is the case of Bothrops cotiara (BC) and B. fonsecai (BF), which are regarded as near threatened with extinction. In this study we conducted a comprehensive analysis of the venom peptidomes of BC, BF, and B. jararaca (BJ) using a combination of solid-phase extraction and reversed-phase HPLC to fractionate the peptides, followed by nano-liquid chromatography-tandem MS (LC-MS/MS) or direct infusion electrospray ionization-(ESI)-MS/MS or MALDI-MS/MS analyses. We detected marked differences in the venom peptidomes and identified peptides ranging from 7 to 39 residues in length by de novo sequencing. Forty-four unique sequences were manually identified, out of which 30 are new peptides, including 17 bradykinin-potentiating peptides, three poly-histidine-poly-glycine peptides and interestingly, 10 l-amino acid oxidase fragments. Some of the new bradykinin-potentiating peptides display significant bradykinin potentiating activity. Automated database search revealed fragments from several toxins in the peptidomes, mainly from l-amino acid oxidase, and allowed the determination of the peptide bond specificity of proteinases and amino acid occurrences for the P4-P4′ sites. We also demonstrate that the venom lyophilization/resolubilization process greatly increases the complexity of the peptidome because of the imbalance caused to the venom proteome and the consequent activity of proteinases on venom components. The use of proteinase inhibitors clearly showed
Pessati, M.L.; Fontana, J.D.; Guimaraes, M.F. [Federal Univ. of Parana, Curitiba (Brazil)
Toxins, enzymes, and biologically active peptides are the main components of snake venoms from the genus Bothrops. Following the venom inoculation, the local effects are hemorrhage, edema, and myonecrosis. Nineteen different species of Brazilian Bothrops were screened for protein content and L-amino acid oxidase activity. B. cotiara, formerly found in the South of Brazil, is now threatened with extinction. Its venom contains a highly hemorrhagic fraction and, as expected from the deep yellow color of the corresponding lyophilized powder, a high L-amino acid oxidase (LAO) activity was also characterized. Flavin adenine dinucleotide (FAD) is its associate coenzyme. B. cotiara venom LAO catalyzed the oxidative deamination of several L-amino acids, and the best substrates were methionine, leucine, tryptophan, and phenylalanine, hence, its potential application for the use in biosensors for aspartame determination and for the removal of amino acids from plasma. High levels for LAO were also found in other species than B. cotiara. In addition, the technique of isoelectric focusing (IEF) was employed as a powerful tool to study the iso- or multi-enzyme distribution for LAO activity in the B. cotiara snake venom.
Rokyta, Darin R; Margres, Mark J; Calvin, Kate
Protein expression is a major link in the genotype-phenotype relationship, and processes affecting protein abundances, such as rates of transcription and translation, could contribute to phenotypic evolution if they generate heritable variation. Recent work has suggested that mRNA abundances do not accurately predict final protein abundances, which would imply that post-transcriptional regulatory processes contribute significantly to phenotypes. Post-transcriptional processes also appear to buffer changes in transcriptional patterns as species diverge, suggesting that the transcriptional changes have little or no effect on the phenotypes undergoing study. We tested for concordance between mRNA and protein expression levels in snake venoms by means of mRNA-seq and quantitative mass spectrometry for 11 snakes representing 10 species, six genera, and three families. In contrast to most previous work, we found high correlations between venom gland transcriptomes and venom proteomes for 10 of our 11 comparisons. We tested for protein-level buffering of transcriptional changes during species divergence by comparing the difference between transcript abundance and protein abundance for three pairs of species and one intraspecific pair. We found no evidence for buffering during divergence of our three species pairs but did find evidence for protein-level buffering for our single intraspecific comparison, suggesting that buffering, if present, was a transient phenomenon in venom divergence. Our results demonstrated that post-transcriptional mechanisms did not contribute significantly to phenotypic evolution in venoms and suggest a more prominent and direct role for cis-regulatory evolution in phenotypic variation, particularly for snake venoms. Copyright © 2015 Rokyta et al.
Adukauskienė, Dalia; Varanauskienė, Eglė; Adukauskaitė, Agnė
More than 5 million people are bitten by venomous snakes annually and more than 100,000 of them die. In Europe, one person dies due to envenomation every 3 years. There is only one venomous snake species in Lithuania--the common adder (Vipera berus)--which belongs to the Viperidae family; however, there are some exotic poisonous snakes in the zoos and private collections, such as those belonging to the Elapidae family (cobras, mambas, coral snakes, etc.) and the Crotalidae subfamily of the Viperidae family (pit vipers, such as rattlesnakes). Snake venom can be classified into hemotoxic, neurotoxic, necrotoxic, cardiotoxic, and nephrotoxic according to the different predominant effects depending on the family (i.e., venom of Crotalidae and Viperidae snakes is more hemotoxic and necrotoxic, whereas venom of Elapidae family is mainly neurotoxic). The intoxication degree is estimated according to the appearance of these symptoms: 1) no intoxication ("dry" bite); 2) mild intoxication (local edema and pain); 3) moderate intoxication (pain, edema spreading out of the bite zone, and systemic signs); 4) severe intoxication (shock, severe coagulopathy, and massive edemas). This topic is relevant because people tend to make major mistakes providing first aid (e.g., mouth suction, wound incision, and application of ice or heat). Therefore, this article presents the essential tips on how first aid should be performed properly according to the "Guidelines for the Management of Snake-Bites" by the World Health Organization (2010). Firstly, the victim should be reassured. Rings or other things must be removed preventing constriction of the swelling limb. Airway/breathing must be maintained. The bitten limb should be immobilized and kept below heart level to prevent venom absorption and systemic spread. Usage of pressure bandage is controversial since people usually apply it improperly. Incision, mouth suction, or excision should not be performed; neither a tourniquet nor ice or
Rogalski, Aymeric; Soerensen, Christoffer; Op den Brouw, Bianca; Lister, Callum; Dashevsky, Daniel; Arbuckle, Kevin; Gloria, Alexandra; Zdenek, Christina N; Casewell, Nicholas R; Gutiérrez, José María; Wüster, Wolfgang; Ali, Syed A; Masci, Paul; Rowley, Paul; Frank, Nathaniel; Fry, Bryan G
Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortality in parts of Sub-Saharan Africa, the Middle East, and vast regions of Asia, constituting a public health burden exceeding that of almost any other snake genus globally. Venom-induced consumption coagulopathy, owing to the action of potent procoagulant toxins, is one of the most relevant clinical manifestations of envenomings by Echis spp. Clinical experience and prior studies examining a limited range of venoms and restricted antivenoms have demonstrated for some antivenoms an extreme lack of antivenom cross-reactivity between different species of this genus, sometimes resulting in catastrophic treatment failure. This study undertook the most comprehensive testing of Echis venom effects upon the coagulation of human plasma, and also the broadest examination of antivenom potency and cross-reactivity, to-date. 10 Echis species/populations and four antivenoms (two African, two Asian) were studied. The results indicate that the venoms are, in general, potently procoagulant but that the relative dependence on calcium or phospholipid cofactors is highly variable. Additionally, three out of the four antivenoms tested demonstrated only a very narrow taxonomic range of effectiveness in preventing coagulopathy, with only the SAIMR antivenom displaying significant levels of cross-reactivity. These results were in conflict with previous studies using prolonged preincubation of antivenom with venom to suggest effective cross-reactivity levels for the ICP Echi-Tab antivenom. These findings both inform upon potential clinical effects of envenomation in humans and highlight the extreme limitations of available treatment. It is hoped that this will spur efforts into the development of antivenoms with more comprehensive coverage for bites not only from wild snakes but also from specimens widely kept in zoological collections. Copyright © 2017 Elsevier B.V. All rights reserved.
Berdai, M A; Labib, S; Harandou, M
The objective of our study is to describe the epidemiological, clinical, biological, and therapeutic aspects of snake bites in children in northern Morocco. This retrospective study reviewed files of all children admitted to the pediatric intensive care unit of the Hasssan II University Hospital in Fez from April 2011 through April 2013. It includes all children reported by themselves or their family to have been bitten by a snake and all those with traces of snake fangs. This study included 12 children, with a mean age of 9.6 ± 2.9 years. In each case, admission took place the day the envenomation occurred, a mean of 8.8 ± 5.6 hours after the bite. Locoregional signs and edema were seen in all cases, associated with bruising (58%) and blisters (25%). General events, including gastrointestinal, cardiovascular, neurologic, and hemorrhagic signs, affected 83% of the children. Hemostasis disorders occurred in 91% of patients, including profound thrombocytopenia (mean: 27.7 ± 30.7 G/L. All envenomations were grade 2 or grade 3. Analgesia was administered systematically; a fasciotomy was performed in 25% of cases and transfusion of blood products in 66%. Three children (25%) were intubated and two children died (16%). This series is characterized by the severity of the clinical presentations, with a predominance of locoregional complications and hemostasis disorders corresponding to snake-bite syndrome. We conclude that immunotherapy adapted to the local species must be made available to improve the prognosis of this envenomation.
da Silva, Ana Cláudia Rodrigues; Ferreira, Luciana Garcia; Duarte, Maria Eugênia Rabello; Fujii, Mutue Toyota; Sanchez, Eladio Flores; Noseda, Miguel Daniel; Fuly, André Lopes
Snakebite is a serious occupational hazard affecting mainly rural populations of tropical and subtropical developing countries. Lachesis muta (Bushmaster) bites are extremely serious but are rarely reported in the literature. Bushmaster envenomings are characterized by intense local pain, edema, neurotoxicity, hypotension, local hemorrhage, and dramatic systemic alterations. Antivenom treatment has regularly been used for more than a century; however, it fails to neutralize local tissue damage and hemorrhage, leading to morbidity or disabilities in victims. Thus, the production and clinical use of antivenom must be improved. The present work characterizes, for the first time, a sulfated polysaccharide from the red seaweed, Laurencia aldingensis, including its neutralizing effect on some toxic activities of L. muta venom. Chemical and spectroscopic analyses showed that L. aldingensis produces sulfated agarans with the A-units partially C-2 sulfated or 6-O-methoxylated presetting the B-units in the cyclized (3,6-anhydro-α-L-galactose) or in the non-cyclized form (α-L-galactose). The latter is significantly substituted by sulfate groups on C-6. In vitro and in vivo assays showed that this sulfated agaran inhibited hemolysis, coagulation, proteolysis, edema, and hemorrhage of L. muta venom. Neutralization of hemorrhagic activity was also observed when the agaran was administered by different routes and after or before the venom injection. Furthermore, the agaran blocked the edema caused by a phospholipase A2 isolated from the L. muta venom. Experimental evidence therefore indicates that the sulfated agaran of L. aldingensis has potential to aid antivenom therapy of accidents caused by L. muta venom and may help to develop more effective antivenom treatments of snake bites in general.
Cecchini, Alessandra L; Marcussi, Silvana; Silveira, Lucas B; Borja-Oliveira, Caroline R; Rodrigues-Simioni, Léa; Amara, Susan; Stábeli, Rodrigo G; Giglio, José R; Arantes, Eliane C; Soares, Andreimar M
The venoms of Micrurus lemniscatus carvalhoi, Micrurus frontalis frontalis, Micrurus surinamensis surinamensis and Micrurus nigrocinctus nigrocinctus were assayed for biological activities. Although showing similar liposome disrupting and myotoxic activities, M. frontalis frontalis and M. nigrocinctus nigrocinctus displayed higher anticoagulant and phospholipase A2 (PLA2) activities. The latter induced a higher edema response within 30 min. Both venoms were the most toxic as well. In the isolated chick biventer cervicis preparation, M. lemniscatus carvalhoi venom blocked the indirectly elicited twitch-tension response (85+/-0.6% inhibition after a 15 min incubation at 5 microg of venom/mL) and the response to acetylcholine (ACh; 55 or 110 microM), without affecting the response to KCl (13.4 mM). In mouse phrenic nerve-diaphragm preparation, the venom (5 microg/mL) produced a complete inhibition of the indirectly elicited contractile response after 50 min incubation and did not affect the contractions elicited by direct stimulation. M. lemniscatus carvalhoi inhibited 3H-L-glutamate uptake in brain synaptosomes in a Ca2+-, but not time, dependent manner. The replacement of Ca2+ by Sr2+ and ethylene glycol-bis(beta-aminoethyl ether) (EGTA), or alkylation of the venom with p-bromophenacyl bromide (BPB), inhibited 3H-L-glutamate uptake. M. lemniscatus carvalhoi venom cross-reacted with postsynaptic alpha-neurotoxins short-chain (antineurotoxin-II) and long-chain (antibungarotoxin) antibodies. It also cross-reacted with antimyotoxic PLA2 antibodies from M. nigrocinctus nigrocinctus (antinigroxin). Our results point to the need of catalytic activity for these venoms to exert their neurotoxic activity efficiently and to their components as attractive tools for the study of molecular targets on cell membranes.
Ahmad,Mustaq; Weber,Andréia D.; Zanon,Graciane; Tavares,Luciana de C.; Ilha,Vinicius; Dalcol,Ionara I.; F. Morel,Ademir
The in vitro activity of chelerythrine and lupeol, two metabolites isolated from Zanthoxylum rhoifolium were studied against the venom of the snake Bungarus sindanus (Elapidae). The venom, which is highly toxic to humans, consists mainly by the enzyme acetylcholinesterase (AChE). Both compounds showed activity against the venom, and the alkaloid chelerythrine presented higher activity than did triterpene lupeol. A atividade in vitro de queleritrina e lupeol, dois metabólitos isolados de Za...
Whiteley, Gareth; Logan, Rhiannon A E; Leung, Kam-Yin D; Newberry, Fiona J; Rowley, Paul D; Dunbar, John P; Wagstaff, Simon C; Casewell, Nicholas R; Harrison, Robert A
Snake venoms contain many proteinaceous toxins that can cause severe pathology and mortality in snakebite victims. Interestingly, mRNA encoding such toxins can be recovered directly from venom, although yields are low and quality is unknown. It also remains unclear whether such RNA contains information about toxin isoforms and whether it is representative of mRNA recovered from conventional sources, such as the venom gland. Answering these questions will address the feasibility of using venom-derived RNA for future research relevant to biomedical and antivenom applications. Venom was extracted from several species of snake, including both members of the Viperidae and Elapidae, and either lyophilized or immediately added to TRIzol reagent. TRIzol-treated venom was incubated at a range of temperatures (4-37°C) for a range of durations (0-48 hours), followed by subsequent RNA isolation and assessments of RNA quantity and quality. Subsequently, full-length toxin transcripts were targeted for PCR amplification and Sanger sequencing. TRIzol-treated venom yielded total RNA of greater quantity and quality than lyophilized venom, and with quality comparable to venom gland-derived RNA. Full-length sequences from multiple Viperidae and Elapidae toxin families were successfully PCR amplified from TRIzol-treated venom RNA. We demonstrated that venom can be stored in TRIzol for 48 hours at 4-19°C, and 8 hours at 37°C, at minimal cost to RNA quality, and found that venom RNA encoded multiple toxin isoforms that seemed homologous (98-99% identity) to those found in the venom gland. The non-invasive experimental modifications we propose will facilitate the future investigation of venom composition by using venom as an alternative source to venom gland tissue for RNA-based studies, thus obviating the undesirable need to sacrifice snakes for such research purposes. In addition, they expand research horizons to rare, endangered or protected snake species and provide more
Nunes, E. S.; Souza, M. A. A.; Vaz, A. F. M.; Coelho, L. C. B. B.; Aguiar, J. S.; Silva, T. G.; Guarnieri, M. C.; Melo, A. M. M. A.; Oliva, M. L. V.; Correia, M. T. S.
Gamma radiation alters the molecular structure of biomolecules and is able to mitigate the action of snake venoms and their isolated toxins. The effect of γ-radiation on the folding of Bothrops lecurus venom lectin was measured by a hemagglutinating assay, intrinsic and bis-ANS fluorescence. Intrinsic and bis-ANS fluorescence analyses indicated that irradiation caused unfolding followed by aggregation of the lectin. Our results suggest that irradiation can lead to significant changes in the protein structure, which may promote the loss of its binding property and toxic action.
Lomonte, Bruno; Rey-Suárez, Paola; Fernández, Julián; Sasa, Mahmood; Pla, Davinia; Vargas, Nancy; Bénard-Valle, Melisa; Sanz, Libia; Corrêa-Netto, Carlos; Núñez, Vitelbina; Alape-Girón, Alberto; Alagón, Alejandro; Gutiérrez, José María; Calvete, Juan J
The application of proteomic tools to the study of snake venoms has led to an impressive growth in the knowledge about their composition (venomics), immunogenicity (antivenomics), and toxicity (toxicovenomics). About one-third of all venomic studies have focused on elapid species, especially those of the Old World. The New World elapids, represented by coral snakes, have been less studied. In recent years, however, a number of venomic studies on Micrurus species from North, Central, and South America have been conducted. An overview of these studies is presented, highlighting the emergence of some patterns and trends concerning their compositional, functional, and immunological characteristics. Results gathered to date, encompassing 18 out of the approximately 85 species of Micrurus, reveal a dichotomy of venom phenotypes regarding the relative abundance of the omnipresent phospholipases A 2 (PLA 2 ) and 'three-finger' toxins (3FTx): a group of species express a PLA 2 -predominant venom composition, while others display a 3FTx-predominant compositional pattern. These two divergent toxin expression phenotypes appear to be related to phylogenetic positions and geographical distributions along a North-South axis in the Americas, but further studies encompassing a higher number of species are needed to assess these hypotheses. The two contrasting phenotypes also show correlations with some toxic functionalities, complexity in the diversity of proteoforms, and immunological cross-recognition patterns. The biological significance for the emergence of a dichotomy of venom compositions within Micrurus, in some cases observed even among sympatric species that inhabit relatively small geographic areas, represents a puzzling and challenging area of research which warrants further studies. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lee, H F; Lee, J D; Lee, Y C
In course of immunizing horses with snake venoms, tetanus and diphtheria toxoids, a new serum component, T-globulin, was formed and migrated between the beta- and gamma-globulins. The T-globulin content was parallel with the antibody titre after the middle course of immunization. There were many components in snake antivenin and T-globulin was composed of most of those components. The components of diphtheria T-globulin were the same as those of crude antitoxin and tetanus T-globulin except one precipitin.
CALVETE, Juan J.; PÉREZ, Alicia; LOMONTE, Bruno; SÁNCHEZ, Elda E.; SANZ, Libia
We report the proteomic and antivenomic characterization of Crotalus tigris venom. This venom exhibits the highest lethality for mice among rattlesnakes and the simplest toxin proteome reported to date. The venom proteome of C. tigris comprises 7–8 gene products from 6 toxin families: the presynaptic β-neurotoxic heterodimeric PLA2, Mojave toxin, and two serine proteinases comprise, respectively, 66% and 27% of the C. tigris toxin arsenal, whereas a VEGF-like protein, a CRISP molecule, a medium-sized disintegrin, and 1–2 PIII-SVMPs, each represents 0.1–5% of the total venom proteome. This toxin profile really explains the systemic neuro- and myotoxic effects observed in envenomated animals. In addition, we found that venom lethality of C. tigris and other North American rattlesnake type II venoms correlates with the concentration of Mojave toxin A-subunit, supporting the view that the neurotoxic venom phenotype of crotalid type II venoms may be described as a single-allele adaptation. Our data suggest that the evolutionary trend towards neurotoxicity, which has been also reported for the South American rattlesnakes, may have resulted by paedomorphism. The ability of an experimental antivenom to effectively immunodeplete proteins from the type II venoms of C. tigris, C. horridus, C. oreganus helleri, C. scutulatus scutulatus, and S. catenatus catenatus, indicated the feasibility of generating a pan-American anti-Crotalus type II antivenom, suggested by the identification of shared evolutionary trends among South American and North American Crotalus. PMID:22181673
neurotoxicity has been described after South African green mamba bites.) ... that can fold back into a protected sheath against the roof of the ..... 15. Green mamaba (Dendroaspis angusticeps). Average length. 180 - 200 cm. It is coloured uniformly bright green with undersurface pale green. The mouth lining is bluish white.
G. C. Ferraro
Full Text Available The aim of this study was to evaluate the effect of snake venom derived fibrin glue on the healing of the deep digital flexor tendon, during three periods. The tendon of the 2nd digit of 30 thoracic limbs of dogs was partially sectioned for glue application. Biopsies were performed 7, 15, and 30 days post surgery for the clinical and morphological study of tendons. Analysis of the results showed that 73.3% of the tendons showed stump retraction and 16.6% moderate to excessive adherence, which affected sliding. There was a significant difference in the number of inflammatory cells among the three studied periods, being the highest on day 15. The morphological analysis revealed a typical tendon healing process with a lower level of inflammation in the acute phase, facilitating the cicatricial maturation phase. Snake venom derived fibrin glue promotes the healing in dog flexor tendon.
Liao, Keren; Yang, Mengxue
Snakebite envenomation is a neglected global health problem, causing substantial mortality, disability, and psychological morbidity, especially in rural tropical and subtropical zones. Antivenin is currently the only specific medicine for envenomation. However, it is restricted by cold storage, snakebite diagnosis, and high price. Snake venom phospholipase A2s (svPLA2s) are found in all kinds of venomous snake families (e.g., Viperidae, Elapidae, and Colubridae). Along with their catalytic activity, svPLA2s elicit a wide variety of pharmacological effects that play a pivotal role in envenomation damage. Hence, neutralization of the svPLA2s could weaken or inhibit toxic damage. Here we overviewed the latest knowledge on the distribution, pathophysiological effects, and inhibitors of svPLA2s to elucidate the potential for a novel, wide spectrum antivenom drug targeting svPLA2s. PMID:29318152
Full Text Available Snakebite envenomation is a neglected global health problem, causing substantial mortality, disability, and psychological morbidity, especially in rural tropical and subtropical zones. Antivenin is currently the only specific medicine for envenomation. However, it is restricted by cold storage, snakebite diagnosis, and high price. Snake venom phospholipase A2s (svPLA2s are found in all kinds of venomous snake families (e.g., Viperidae, Elapidae, and Colubridae. Along with their catalytic activity, svPLA2s elicit a wide variety of pharmacological effects that play a pivotal role in envenomation damage. Hence, neutralization of the svPLA2s could weaken or inhibit toxic damage. Here we overviewed the latest knowledge on the distribution, pathophysiological effects, and inhibitors of svPLA2s to elucidate the potential for a novel, wide spectrum antivenom drug targeting svPLA2s.
Leão, Luciana I; Ho, Paulo L; Junqueira-de-Azevedo, Inacio de L M
Micrurus corallinus (coral snake) is a tropical forest snake belonging to the family Elapidae. Its venom shows a high neurotoxicity associated with pre- and post-synaptic toxins, causing diaphragm paralysis, which may result in death. In spite of a relatively small incidence of accidents, serum therapy is crucial for those bitten. However, the adequate production of antiserum is hampered by the difficulty in obtaining sufficient amounts of venom from a small snake with demanding breeding conditions. In order to elucidate the molecular basis of this venom and to uncover possible immunogens for an antiserum, we generated expressed sequences tags (ESTs) from its venom glands and analyzed the transcriptomic profile. In addition, their immunogenicity was tested using DNA immunization. A total of 1438 ESTs were generated and grouped into 611 clusters. Toxin transcripts represented 46% of the total ESTs. The two main toxin classes consisted of three-finger toxins (3FTx) (24%) and phospholipases A(2) (PLA(2)s) (15%). However, 8 other classes of toxins were present, including C-type lectins, natriuretic peptide precursors and even high-molecular mass components such as metalloproteases and L-amino acid oxidases. Each class included an assortment of isoforms, some showing evidence of alternative splicing and domain deletions. Five antigenic candidates were selected (four 3FTx and one PLA(2)) and used for a preliminary study of DNA immunization. The immunological response showed that the sera from the immunized animals were able to recognize the recombinant antigens. Besides an improvement in our knowledge of the composition of coral snake venoms, which are very poorly known when compared to Old World elapids, the expression profile suggests abundant and diversified components that may be used in future antiserum formulation. As recombinant production of venom antigens frequently fails due to complex disulfide arrangements, DNA immunization may be a viable alternative. In
Ho Paulo L
Full Text Available Abstract Background Micrurus corallinus (coral snake is a tropical forest snake belonging to the family Elapidae. Its venom shows a high neurotoxicity associated with pre- and post-synaptic toxins, causing diaphragm paralysis, which may result in death. In spite of a relatively small incidence of accidents, serum therapy is crucial for those bitten. However, the adequate production of antiserum is hampered by the difficulty in obtaining sufficient amounts of venom from a small snake with demanding breeding conditions. In order to elucidate the molecular basis of this venom and to uncover possible immunogens for an antiserum, we generated expressed sequences tags (ESTs from its venom glands and analyzed the transcriptomic profile. In addition, their immunogenicity was tested using DNA immunization. Results A total of 1438 ESTs were generated and grouped into 611 clusters. Toxin transcripts represented 46% of the total ESTs. The two main toxin classes consisted of three-finger toxins (3FTx (24% and phospholipases A2 (PLA2s (15%. However, 8 other classes of toxins were present, including C-type lectins, natriuretic peptide precursors and even high-molecular mass components such as metalloproteases and L-amino acid oxidases. Each class included an assortment of isoforms, some showing evidence of alternative splicing and domain deletions. Five antigenic candidates were selected (four 3FTx and one PLA2 and used for a preliminary study of DNA immunization. The immunological response showed that the sera from the immunized animals were able to recognize the recombinant antigens. Conclusion Besides an improvement in our knowledge of the composition of coral snake venoms, which are very poorly known when compared to Old World elapids, the expression profile suggests abundant and diversified components that may be used in future antiserum formulation. As recombinant production of venom antigens frequently fails due to complex disulfide arrangements, DNA
Lima, Rebeca Mascarenhas; Estevão-Costa, Maria Inácia; Junqueira-de-Azevedo, Inácio L M; Ho, Paulo Lee; Diniz, Marcelo Ribeiro Vasconcelos; Fortes-Dias, Consuelo Latorre
Phospholipase A(2) inhibitors (PLIs) are glycoproteins secreted by snake liver into the circulating blood aiming the self-protection against toxic venom phospholipases A(2). In the present study, we describe the first complete nucleotide sequence of a βPLI from venom glands of a New World snake, Lachesis muta. The deduced primary structure was compared to other known βPLIs and recent literature findings of other possible roles of PLIs in snakes are discussed. Copyright Â© 2010 Elsevier Ltd. All rights reserved.
Lynch Vincent J
Abstract Background Gene duplication followed by functional divergence has long been hypothesized to be the main source of molecular novelty. Convincing examples of neofunctionalization, however, remain rare. Snake venom phospholipase A2 genes are members of large multigene families with many diverse functions, thus they are excellent models to study the emergence of novel functions after gene duplications. Results Here, I show that positive Darwinian selection and neofunctionalization is com...
Maria de Fátima Neves Sandrin; Giuseppe Puorto; Roberto Nardi
The subject venomous snakes is pointed out as a problem in science education textbooks in Brazil, due to the high rate of conceptual mistakes. Aiming to help teachers in that subject, we analyzed a total of 27 textbooks published in the period 1982 to 1999. The criteria used in the conceptual analysis were based scientific correction and the presence of non-scientific classification. In relation to the conceptual analysis, data collected showed predominance of problems related to the biology ...
Catherine A Vulfius
Full Text Available Phospholipases A2 represent the most abundant family of snake venom proteins. They manifest an array of biological activities, which is constantly expanding. We have recently shown that a protein bitanarin, isolated from the venom of the puff adder Bitis arietans and possessing high phospholipolytic activity, interacts with different types of nicotinic acetylcholine receptors and with the acetylcholine-binding protein. To check if this property is characteristic to all venom phospholipases A2, we have studied the capability of these enzymes from other snakes to block the responses of Lymnaea stagnalis neurons to acetylcholine or cytisine and to inhibit α-bungarotoxin binding to nicotinic acetylcholine receptors and acetylcholine-binding proteins. Here we present the evidence that phospholipases A2 from venoms of vipers Vipera ursinii and V. nikolskii, cobra Naja kaouthia, and krait Bungarus fasciatus from different snake families suppress the acetylcholine- or cytisine-elicited currents in L. stagnalis neurons and compete with α-bungarotoxin for binding to muscle- and neuronal α7-types of nicotinic acetylcholine receptor, as well as to acetylcholine-binding proteins. As the phospholipase A2 content in venoms is quite high, under some conditions the activity found may contribute to the deleterious venom effects. The results obtained suggest that the ability to interact with nicotinic acetylcholine receptors may be a general property of snake venom phospholipases A2, which add a new target to the numerous activities of these enzymes.
Tanaka, Gabriela D; Sant'Anna, Osvaldo Augusto; Marcelino, José Roberto; Lustoza da Luz, Ana Cristina; Teixeira da Rocha, Marisa Maria; Tambourgi, Denise V
Micrurus snakebites can cause death by muscle paralysis and respiratory arrest a few hours after envenomation. The specific treatment for these snake envenomations is the intravenous application of heterologous antivenom. In Brazil, this antivenom is produced from horses that are immunized with a mixture of Micrurus corallinus and Micrurus frontalis venoms, which are snakes that inhabit the south and southeastern regions of the country. Previously, we demonstrated that the coral antivenom, which is used in human therapy, was not able to neutralize several of the toxic venom effects from some Micrurus species that inhabit the country, as measured by in vitro and in vivo assays. The present study aimed to investigate the immunogenic properties of Micrurus spp. venoms, as well as the cross-reactivity and neutralization potential of experimental monovalent and polyvalent sera that were produced in different animal species. The present data showed that Micrurus venoms exhibited the same immunogenicity pattern in the three utilized animal species and that the specific antisera presented a large cross-reactivity when analyzed with ELISA and Western blot assays. Nonetheless, these positive results were not well correlated with the neutralizing potential of the antisera. Thus, the establishment of a new antigenic mixture to produce novel more efficient therapeutic Micrurus antivenom is not a simple task. Further studies, particularly with the Micrurus lemniscatus, Micrurus altirostris and Micrurus surinamensis venoms, are necessary to establish new strategies for the production of antivenoms with broad neutralizing activity for the treatment of accidents involving coral snakes throughout the country. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sujay Kumar Bhunia
Full Text Available The re-emergence of multidrug-resistant tuberculosis (MDR-TB has brought to light the importance of screening effective novel drugs. In the present study, in vitro activities of different snake (Naja naja, Bungarus fasciatus, Daboia russelli russelli, Naja kaouthia venoms have been investigated against clinical isolate of MDR-TB strains. The treatment with all the venoms inhibited the mycobacterial growth for at least a week in common and two of them (Naja naja and Naja kaouthia showed significantly longer inhibition up to two weeks against the MDR-TB strain with single dose and a repetition of those two venoms exhibited inhibition up to more than four weeks.
Full Text Available Pergularia daemia (Forsk. chiov., is a milk weed of Asclepiadaceae family. In the present study β-sitosterol, β-amyrin, α-amyrin and lupeol were identified in the leaf by GC–MS. Molecular docking studies were performed to evaluate their activities on phospholipase A2 (PLA2 and l-amino acid oxidase enzymes which constituted a rich source in snake venoms (Naja naja. Snake venom Phospholipase A2 with PDB code 1A3D devoid of co-crystallized ligand was extracted from Protein Data Bank. Using Molegro Virtual Docker two cavities are formed by cocrystallization. l-Amino acid oxidase (PDB code 4E0V was a receptor model with a co-crystallized ligand FAD. Among the phytochemicals analysed, β-sitosterol displayed high affinity of binding to the active site regions of phospholipase A2 and l-amino acid oxidase, respectively. The affinity of binding was −125.939 and −157.521 kcal/mole identified by gold scores. α-Amyrin and β-amyrin had two hydrogen bond interactions with PLA2. Hence this study suggests that β-sitosterol identified in P. daemia can antagonize PLA2 and LAAO activities and forms a theoretical basis for the folk use of the plant against snake venom.
Maria de Fátima Neves Sandrin
Full Text Available The subject venomous snakes is pointed out as a problem in science education textbooks in Brazil, due to the high rate of conceptual mistakes. Aiming to help teachers in that subject, we analyzed a total of 27 textbooks published in the period 1982 to 1999. The criteria used in the conceptual analysis were based scientific correction and the presence of non-scientific classification. In relation to the conceptual analysis, data collected showed predominance of problems related to the biology of snakes, identification and differentiation among venomous and non-venomous ones, incorrect self-care instructions, inappropriate attendance care in case of venomous’ snakes accident, besides the use of anthropocentric concepts. Data collected showed also that in most of the textbooks problematization and contextualization are not considered in despite of the descriptive form, predominant citation of the animal’s anatomical data, nomenclature and definitions. Proportionally, it was found higher number of problems in science textbooks than in those destined to high school biology.
Georgieva, Dessislava; Hildebrand, Diana; Simas, Rodrigo; Coronado, Monika A; Kwiatkowski, Marcel; Schlüter, Hartmut; Arni, Raghuvir; Spencer, Patrick; Betzel, Christian
The Pseudechis colletti and Pseudechis butleri venoms were analyzed by 1-D gel electrophoresis, followed by mass spectrometric analysis of tryptic peptides obtained from the protein bands. Both venoms contain highly potent pharmacologically active components, which were assigned to the following protein families: basic and acidic phospholipases A2 (PLA2s), L-amino acid oxidases (LAAOs), P-III metalloproteinases (P-III SVMPs), 5'- nucleotidases (5'-NTDs), cysteine-rich secretory proteins (CRISPs), venom nerve growth factors (VNGFs) and post-synaptic neurotoxins. Considerable predominance of PLA2s over other toxins is a characteristic feature of both venoms. The major differences in the venom compositions are the higher concentration of SVMPs and CRISPs in the P. butleri venom, as well as the presence of post-synaptic neurotoxins. Furthermore, the analysis revealed a high concentration of proteins with myotoxic, coagulopathic and apoptotic activities. PLA2s are responsible for the myotoxic and anticoagulant effects observed in patients after envenomation (4). The other protein families, encountered in the two venoms, probably contribute to the major symptoms described for these venoms. These results explain the observed clinical effects of the black snake envenomation. The analyzed venoms contain group P-III metalloproteinases of medical importance with the potency to be used for diagnostic purposes of von Willebrand factor (vWF) disease, for regulation of vWF in thrombosis and haemostasis, for studying the function of the complement system in host defense and in the pathogenesis of diseases. Comparison of venomic data showed similarities in the major venom components of snakes from the genus Pseudechis, resulting in common clinical effects of envenomation, and demonstrating close relationships between venom toxins of Elapidae snakes. Copyright© Bentham Science Publishers; For any queries, please email at email@example.com.
Abraham Jobin; Rai Neeta
Recommendation of the effective dose to the medical facility and all the possible condition. Much of the first aid currently carried out is ineffective and dangerous The right method will get the victim to the hospital quickly, without recourse to traditional medical approaches which can dangerously delay effective treatment and will supply the doctor with the best possible information on arrival .Different consideration of the inapplicable method like PIM different treatment of the snake bit...
Ribeiro Filho, Wilker; Sugiki, Masahiko; Yoshida, Etsuo; Maruyama, Masugi
In order to obtain basic data on the effect of broad-spectrum protease inhibitor against local symptoms of Viperidae snake envenomation, inhibitory capacity of rat murinoglobulin on local hemorrhagic and edematogenic activities of venoms from Crotalus atrox, Bothrops jararaca, Lachesis muta muta, Trimeresurus flavoviridis and Echis carinatus sochureki were examined. Murinoglobulin, pre-incubated with the crude venoms at 37 degrees C for 15 min, inhibited hemorrhagic activity of all five venoms to various extents. The activity of C. atrox was almost completely inhibited at the murinoglobulin/venom ratio (w/w) of 20. The activity of B. jararaca, Lachesis muta muta and T. flavoviridis venoms was considerably inhibited at the ratio of 20 (77.2, 80.0 and 86.2% inhibition, respectively), however some of the activity still remained even at the ratio of 40 (84.2, 79.8 and 86.2% inhibition, respectively). Among the five venoms, E. c. sochureki venom is quite resistant to murinoglobulin treatment and statistically significant inhibition was only found at the ratio of 40 (64.1% inhibition). Fibrinolytic and gelatinase activities were more susceptible to murinoglobulin inhibition. The treatment at the ratios of 10 and 20 almost completely inhibited respectively the fibrinolytic and the gelatinase activities of all the venoms. Murinoglobulin treatment also significantly inhibited the edematogenic activity of L. muta muta, T. flavoviridis and Echis carinatus sochureki. The treatment of murinoglobulin at the ratio of 40 considerably suppressed the swelling up to 60 min after subcutaneous injection of L. muta muta and E. c. sochureki venoms, and up to 30 min after T. flavoviridis venom injection. Murinoglobulin is a potent inhibitor against local effects of multiple snake venoms in Viperidae family.
Adrija Hajra; Dhrubajyoti Bandyopadhyay
Viper venoms act mainly as hemotoxic. Manifestations of snakebites depend on specific toxins that constitute the venom. The local and systemic snake bite related symptoms are directly linked to the toxicity of the venom. Edema, ecchymoses, hematoma, and gangrenous lesions are reported to occur as local symptoms. Systemic symptoms may include fever, nausea, vomiting, delirium, jaundice, circulatory collapse, convulsions, and coma. Death from secondary infections, neurotoxicity, disseminated in...
Engmark, Mikael; Andersen, Mikael Rørdam; Laustsen, Andreas Hougaard
Insight into the molecular details of polyclonal antivenom antibody specificity is a prerequisite for accurate prediction of cross-reactivity and can provide a basis for design of novel antivenoms. In this work, a highthroughput approach was applied to characterize linear elements in epitopes in ...... toxins from four African mamba and three neurotoxic cobra snakes obtained from public databases....
Full Text Available Abdulrahman Khazim Al-Asmari,1 Anvarbatcha Riyasdeen,1 Mohammad Hamed Al-Shahrani,2 Mozaffarul Islam1 1Research Center, 2Pediatric Hematology/Oncology and Bone Marrow Transplant Unit, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia Abstract: Snake venom possesses various kinds of proteins and neurotoxic polypeptides, which can negatively interfere with the neurotransmitter signaling cascade. This phenomenon occurs mainly due to the blocking of ion channels in the body system. Envenomation prevents or severely interrupts nerve impulses from being transmitted, inhibition of adenosine triphosphate synthesis, and proper functioning of the cardiac muscles. However, some beneficial properties of venoms have also been reported. The aim of this study was to examine the snake venom as an anticancer agent due to its inhibitory effects on cancer progression such as cell motility, cell invasion, and colony formation. In this study, the effect of venoms on phenotypic changes and the change on molecular level in colorectal and breast cancer cell lines were examined. A reduction of 60%–90% in cell motility, colony formation, and cell invasion was observed when these cell lines were treated with different concentrations of snake venom. In addition, the increase in oxidative stress that results in an increase in the number of apoptotic cancer cells was significantly higher in the venom-treated cell lines. Further analysis showed that there was a decrease in the expression of pro-inflammatory cytokines and signaling proteins, strongly suggesting a promising role for snake venom against breast and colorectal cancer cell progression. In conclusion, the snake venoms used in this study showed significant anticancer properties against colorectal and breast cancer cell lines. Keywords: colorectal cancer, breast cancer, cell motility, colony formation, oxidative stress, apoptosis, IL-8, IL-6, RhoC, p-Erk1/2
Huang, Hsuan-Wei; Liu, Bing-Sin; Chien, Kun-Yi; Chiang, Liao-Chun; Huang, Sheng-Yu; Sung, Wang-Chou; Wu, Wen-Guey
Recent progress in snake venomics has shed much light on the intra-species variation among the toxins from different geographical regions and has provided important information for better snakebite management. Most previous reports on snake venomics were based on venoms pooled from different snakes. In this study, we present the proteomic and glycomic profiles of venoms from individual Naja atra snakes. The results reveal wide dynamic range of three-finger toxins. Systematic classification based on cardiotoxin (CTX-) profiles of A2/A4 and A6, respectively, allowed the identification of two putative subspecies of Taiwan cobra from the eastern and western regions. We also identified four major N-glycan moieties on cobra snake venom metalloproteinase on the bi-antennary glycan core. ELISA showed that these glycoproteins (cobra venom toxins such as small molecular weight CTXs (~60%). By removing these high-molecular weight glycoproteins from the immunogen, we demonstrated better protection than that achieved with conventional crude venom immunization in mice challenged by crude venom. We conclude that both intra-species and inter-individual variations of proteomic and glycomic profiles of snake venomics should be considered to provide better antivenomic approach for snakebite management. Based on the proteomic and glycomic profiles of venoms obtained from individual snakes, we demonstrated a surprisingly wide dynamic range and geographical variation of three-finger toxins in cobra venomics. This provides a reasonable explanation for the variable neutralization effects of antivenom treatment on victims suffering from cobra snakebite and suggests a simple and economic method to produce potent antivenom with better efficacy. Since two major venomic profiles with distinct dynamic ranges were observed for Taiwan cobra venoms isolated from the eastern and western regions, the current venomic profile should be used as a quality control for future production of antivenom in
Cockrell, Melanie; Swanson, Kristofer; Sanders, April; Prater, Samuel; von Wenckstern, Toni; Mick, JoAnn
Efforts to improve consistency in management of snakes and venomous snake bites in the emergency department (ED) can improve patient and staff safety and outcomes, as well as improve surveillance data accuracy. The emergency department at a large academic medical center identified an opportunity to implement a standardized process for snake disposal and identification to reduce staff risk exposure to snake venom from snakes patients brought with them to the ED. A local snake consultation vendor and zoo Herpetologist assisted with development of a process for snake identification and disposal. All snakes have been identified and securely disposed of using the newly implemented process and no safety incidents have been reported. Other emergency department settings may consider developing a standardized process for snake disposal using listed specialized consultants combined with local resources and suppliers to promote employee and patient safety. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.
Full Text Available Envenomations caused by different species of Bothrops snakes result in severe local tissue damage, hemorrhage, pain, myonecrosis, and inflammation with a significant leukocyte accumulation at the bite site. However, the activation state of leukocytes is still unclear. According to clinical cases and experimental work, the local effects observed in envenenomation by Bothrops alternatus are mainly the appearance of edema, hemorrhage, and necrosis. In this study we investigated the ability of Bothrops alternatus crude venom to induce macrophage activation. At 6 to 100 ¼g/mL, BaV is not toxic to thioglycollate-elicited macrophages; at 3 and 6 ¼g/mL, it did not interfere in macrophage adhesion or detachment. Moreover, at concentrations of 1.5, 3, and 6 ¼g/mL the venom induced an increase in phagocytosis via complement receptor one hour after incubation. Pharmacological treatment of thioglycollate-elicited macrophages with staurosporine, a protein kinase (PKC inhibitor, abolished phagocytosis, suggesting that PKC may be involved in the increase of serum-opsonized zymosan phagocytosis induced by BaV. Moreover, BaV also induced the production of anion superoxide (O2_ by thioglycollate-elicited macrophages. This BaV stimulated superoxide production was abolished after treating the cells with staurosporine, indicating that PKC is an important signaling pathway for the production of this radical. Based on these results, we suggest that phagocytosis and reactive oxygen species are involved in the pathogenesis of local tissue damage characteristic of Bothrops spp. envenomations.
divergence between A. mexicanus and A. picadoi, and a closer kinship between A. mexicanus and C. godmani. Conclusions Our comparative next-generation sequencing (NGS analysis reveals taxon-specific trends governing the formulation of the venom arsenal. Knowledge of the venom proteome provides hints on the translation efficiency of toxin-coding transcripts, contributing thereby to a more accurate interpretation of the transcriptome. The application of NGS to the analysis of snake venom transcriptomes, may represent the tool for opening the door to systems venomics.
and A. picadoi, and a closer kinship between A. mexicanus and C. godmani. Conclusions Our comparative next-generation sequencing (NGS) analysis reveals taxon-specific trends governing the formulation of the venom arsenal. Knowledge of the venom proteome provides hints on the translation efficiency of toxin-coding transcripts, contributing thereby to a more accurate interpretation of the transcriptome. The application of NGS to the analysis of snake venom transcriptomes, may represent the tool for opening the door to systems venomics. PMID:21605378
Trape, J F; Pison, G; Guyavarch, E; Mane, Y
From 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern Senegal. Of 4,228 deaths registered during this period, 26 were brought on by snakebites, 4 by invertebrate stings and 8 by other wild or domestic animals. The average annual mortality rate from snakebite was 14 deaths per 100,000 population. Among persons aged 1 year or more, 0.9% (26/2,880) of deaths were caused by snakebite and this cause represented 28% (26/94) of the total number of deaths by accident. We also investigated the snake fauna of the area. Of 1,280 snakes belonging to 34 species that were collected, one-third were dangerous and the proportion of Viperidae, Elapidae and Atractaspididae was 23%, 11% and 0.6%, respectively. The saw-scaled viper Echis ocellatus was the most abundant species (13.6%). Other venomous species were Causus maculatus (6.5%), Naja katiensis (5.5%), Bitis arietans (2.7%), Elapsoidea trapei (2.4%), Naja nigricollis (1.2%), Naja melanoleuca (1.1%), Atractaspis aterrima (0.4%), Dendroaspis polylepis (0.3%) and Naja haje (0.1%).
Yang, Daryl C; Deuis, Jennifer R; Dashevsky, Daniel; Dobson, James; Jackson, Timothy N W; Brust, Andreas; Xie, Bing; Koludarov, Ivan; Debono, Jordan; Hendrikx, Iwan; Hodgson, Wayne C; Josh, Peter; Nouwens, Amanda; Baillie, Gregory J; Bruxner, Timothy J C; Alewood, Paul F; Lim, Kelvin Kok Peng; Frank, Nathaniel; Vetter, Irina; Fry, Bryan G
Millions of years of evolution have fine-tuned the ability of venom peptides to rapidly incapacitate both prey and potential predators. Toxicofera reptiles are characterized by serous-secreting mandibular or maxillary glands with heightened levels of protein expression. These glands are the core anatomical components of the toxicoferan venom system, which exists in myriad points along an evolutionary continuum. Neofunctionalisation of toxins is facilitated by positive selection at functional hotspots on the ancestral protein and venom proteins have undergone dynamic diversification in helodermatid and varanid lizards as well as advanced snakes. A spectacular point on the venom system continuum is the long-glanded blue coral snake ( Calliophis bivirgatus ), a specialist feeder that preys on fast moving, venomous snakes which have both a high likelihood of prey escape but also represent significant danger to the predator itself. The maxillary venom glands of C. bivirgatus extend one quarter of the snake's body length and nestle within the rib cavity. Despite the snake's notoriety its venom has remained largely unstudied. Here we show that the venom uniquely produces spastic paralysis, in contrast to the flaccid paralysis typically produced by neurotoxic snake venoms. The toxin responsible, which we have called calliotoxin (δ-elapitoxin-Cb1a), is a three-finger toxin (3FTx). Calliotoxin shifts the voltage-dependence of Na V 1.4 activation to more hyperpolarised potentials, inhibits inactivation, and produces large ramp currents, consistent with its profound effects on contractile force in an isolated skeletal muscle preparation. Voltage-gated sodium channels (Na V ) are a particularly attractive pharmacological target as they are involved in almost all physiological processes including action potential generation and conduction. Accordingly, venom peptides that interfere with Na V function provide a key defensive and predatory advantage to a range of invertebrate
Gilliam, Lyndi L; Ownby, Charlotte L; McFarlane, Dianne; Canida, Amy; Holbrook, Todd C; Payton, Mark E; Krehbiel, Clinton R
Rattlesnake bites in horses are not uncommon and the clinical outcomes are widely variable. Treatment of horses with anti-venom is often cost prohibitive and could have negative consequences; therefore, the development of a quantitative test to determine if anti-venom therapy is indicated would be valuable. The objective of this study was to develop an ELISA to detect rattlesnake venom in biological samples from clinically bitten horses. Nineteen horses were enrolled in the study. Urine was available from 19 horses and bite site samples were available from 9 horses. A double sandwich fluorescent ELISA was developed and venom was detected in 5 of 9 bite site samples and 12 of 19 urine samples. In order to determine if this assay is useful as a guide for treatment, a correlation between venom concentration and clinical outcome needs to be established. For this, first peak venom concentration needs to be determined. More frequent, consistent sample collection will be required to define a venom elimination pattern in horses and determine the ideal sample collection time to best estimate the maximum venom dose. This report describes development of an assay with the ability to detect rattlesnake venom in the urine and at the bite site of horses with a clinical diagnosis of rattlesnake bite. Copyright © 2013 Elsevier Ltd. All rights reserved.
Hassan, F; El-Hawary, M F; El-Ghazawy, A
Non-specific acid and alkaline phosphomonoesterases could be demonstrated in two viperids (Cerastes cerastes and Cerastes vipers) and two elapids (Naja haje and Naja nigricollis). The latter could be a natural source for the production of these enzymes. The activities of both enzymes in elapids were greater than in viperids. N. nigricollis was the only to show acid phosphatase activity exceeding its alkaline one. The optimum pH values recorded for acid phosphatase was 4.0 and 4.9 and for alkaline phosphatase 9.0 and 10.0 in viperids and elapids, respectively. Optimum substrate concentration for both enzymes in viperids was 0.01 M, while for acid phosphatase in N. haje and N. nigricollis it was 0.125 and 0.150 M; and for their alkaline phosphatases the values were 0.150 and 0.125 M, respectively. Mg++ behaved as an activator for both enzymes in all venoms investigated, while Zn++ showed either no or slight activating effect. Fluoride ions as well as EDTA showed certain inhibitory action. Both enzymes in the crude venoms were heat-labile.
Richardson, William H; Tanen, David A; Tong, Tri C; Betten, David P; Carstairs, Shaun D; Williams, Saralyn R; Cantrell, Frank L; Clark, Richard F
North American coral snake antivenin (CSAV; Wyeth Antivenin [Micrurus fulvius], equine origin) is approved for the treatment of coral snake envenomations in the United States. The coral snake is the only elapid that is native to North America, but envenomations from non-native elapids are occurring more commonly in this country. This study was designed to evaluate the efficacy of CSAV in the neutralization of two exotic elapid envenomations: Naja naja (Indian cobra) and Dendroaspis polylepsis (black mamba). A randomized, blinded, placebo-controlled murine model of intraperitoneal venom injection was employed. Venom potency was determined in preliminary dosing studies. Study animals then were divided into five groups: 1) N. naja venom + CSAV, 2) N. naja venom + 0.9% normal saline (NS), 3) D. polylepsis venom + CSAV, 4) D. polylepsis venom + NS, and 5) CSAV + NS. The venom dose was chosen to be twice the estimated LD50. The amount of CSAV injected was ten times the amount necessary for neutralization of a 2 x LD50 dose of M. f. fulvius venom in a murine model. Statistical analysis included Fisher's exact and log-rank testing to compare survival rates and times. Preliminary studies estimated the venom LD50 to be 2.58 mg/kg and 0.45 mg/kg, respectively, for the N. naja and D. polylepsis. A significant difference was shown in comparison of survival times between CSAV-venom groups and normal saline-venom groups despite all animals in both treatment and control arms dying. Animals receiving CSAV and N. naja venom survived (mean +/- SD) 24.4 +/- 3.0 minutes, versus 17.8 +/- 1.3 minutes in the control group (p < 0.001), whereas those receiving CSAV and D. polylepsis venom survived 203.8 +/- 37.0 minutes versus 130.0 +/- 42.6 minutes in the control group (p < 0.001). All animals in the CSAV + NS group survived to the conclusion of the study. When premixed with venom, CSAV increased survival time in a murine model of intraperitoneal N. naja and D. polylepsis venom injection
Olmedo, Hidekel; Herrera, María; Rojas, Leonardo; Villalta, Mauren; Vargas, Mariángela; Leiguez, Elbio; Teixeira, Catarina; Estrada, Ricardo; Gutiérrez, José María; León, Guillermo; Montero, Mavis L
The adjuvanticity of aluminum hydroxide and calcium phosphate on the antibody response in mice towards the venom of the snake Bothrops asper was studied. It was found that, in vitro, most of the venom proteins are similarly adsorbed by both mineral salts, with the exception of some basic phospholipases A2, which are better adsorbed by calcium phosphate. After injection, the adjuvants promoted a slow release of the venom, as judged by the lack of acute toxicity when lethal doses of venom were administered to mice. Leukocyte recruitment induced by the venom was enhanced when it was adsorbed on both mineral salts; however, venom adsorbed on calcium phosphate induced a higher antibody response towards all tested HPLC fractions of the venom. On the other hand, co-precipitation of venom with calcium phosphate was the best strategy for increasing: (1) the capacity of the salt to couple venom proteins in vitro; (2) the venom ability to induce leukocyte recruitment; (3) phagocytosis by macrophages; and (4) a host antibody response. These findings suggest that the chemical nature is not the only one determining factor of the adjuvant activity of mineral salts.
Full Text Available Abstract Background The venom of the family Viperidae, including the saw-scaled viper, is rich in serine proteinases and metalloproteinases, which affect the nervous system, complementary system, blood coagulation, platelet aggregation and blood pressure. One of the most prominent effects of the snake venom of Echis carinatus (Ec is its coagulation activity, used for killing prey. Materials and methods Subfractions F1A and F1B were isolated from Ec crude venom by a combination of gel chromatography (Sephadex G-75 and ion exchange chromatography on a DEAE-Sepharose (DE-52. These subfractions were then intravenously (IV injected into NIH male mice. Blood samples were taken before and after the administration of these subfractions. Times for prothrombin, partial thromboplastin and fibrinogen were recorded. Results and conclusions Comparison of the prothrombin time before and after F1A and F1B administrations showed that time for blood coagulation after injection is shorter than that of normal blood coagulation and also reduced coagulation time after Ec crude venom injection. This difference in coagulation time shows the intense coagulation activity of these subfractions that significantly increase the coagulation cascade rate and Causes to quick blood coagulation. The LD50 of the Ec crude venom was also determined to be 11.1 μg/mouse. Different crude venom doses were prepared with physiological serum and injected into four mice. Comparison of the prothrombin times after injection of subfractions F1A and F1B showed that the rate of mouse blood coagulation increases considerably. Comparing the partial thromboplastin times after injecting these subfractions with this normal test time showed that the activity rate of intrinsic blood coagulation system rose sharply in mice. Finally, by comparing the fibrinogen time after subfraction injections and normal test time, we can infer intense activation of coagulation cascade and fibrin production.
Alam, Md Iqbal; Alam, Mohammed A; Alam, Ozair; Nargotra, Amit; Taneja, Subhash Chandra; Koul, Surrinder
In our earlier study, we have reported that a phenolic compound 2-hydroxy-4-methoxybenzaldehyde from Janakia arayalpatra root extract was active against Viper and Cobra envenomations. Based on the structure of this natural product, libraries of synthetic structurally variant phenolic compounds were studied through molecular docking on the venom protein. To validate the activity of eight selected compounds, we have tested them in in vivo and in vitro models. The compound 21 (2-hydroxy-3-methoxy benzaldehyde), 22 (2-hydroxy-4-methoxybenzaldehyde) and 35 (2-hydroxy-3-methoxybenzylalcohol) were found to be active against venom-induced pathophysiological changes. The compounds 20, 15 and 35 displayed maximum anti-hemorrhagic, anti-lethal and PLA2 inhibitory activity respectively. In terms of SAR, the presence of a formyl group in conjunction with a phenolic group was seen as a significant contributor towards increasing the antivenom activity. The above observations confirmed the anti-venom activity of the phenolic compounds which needs to be further investigated for the development of new anti-snake venom leads. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Sandra H. P. Farsky
Full Text Available The venom of the snake Bothrops asper, the most important poisonous snake in Central America, evokes an inflammatory response, the mechanisms of which are not well characterized. The objectives of this study were to investigate whether B. asper venom and its purified toxins – phospholipases and metalloproteinase – activate the complement system and the contribution of the effect on leucocyte recruitment. In vitro chemotaxis assays were performed using Boyden's chamber model to investigate the ability of serum incubated with venom and its purified toxins to induce neutrophil migration. The complement consumption by the venom was evaluated using an in vitro haemolytic assay. The importance of complement activation by the venom on neutrophil migration was investigated in vivo by injecting the venom into the peritoneal cavity of C5-deficient mice. Data obtained demonstrated that serum incubated with crude venom and its purified metalloproteinase BaP–1 are able to induce rat neutrophil chemotaxis, probably mediated by agent(s derived from the complement system. This hypothesis was corroborated by the capacity of the venom to activate this system in vitro. The involvement of C5a in neutrophil chemotaxis induced by venom-activated serum was demonstrated by abolishing migration when neutrophils were pre-incubated with antirat C5a receptor antibody. The relevance of the complement system in in vivo leucocyte mobilization was further demonstrated by the drastic decrease of this response in C5-deficient mice. Pre-incubation of serum with the soluble human recombinant complement receptor type 1 (sCR 1 did not prevent the response induced by the venom, but abolished the migration evoked by metalloproteinase-activated serum. These data show the role of the complement system in bothropic envenomation and the participation of metalloproteinase in the effect. Also, they suggest that the venom may contain other component(s which can cause direct activation
Gartner, T K; Ogilvie, M L
Three lactose-inhibited lectins from the venoms of the snakes Agkistrodon contortrix contortrix (southern copperhead), Ancistrodon piscivorous leukostoma (western cottonmouth moccasin) and Crotalus atrox (western diamondback rattlesnake) have been isolated and newly characterized. The three lectins are similar to thrombolectin, a lectin isolated from the venom of Bothrops atrox (fer-de-lance) (Gartner, Stocker & Williams, 1980), with regard to sugar specificity, Mr, Ca2+ requirements and sensitivity to reducing agents. Each lectin is a dimer (Mr 28 000) consisting of monomers (Mr 14 000) indistinguishable on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Haemagglutination activity is dependent on the presence of Ca2+ and is inhibited by reducing agents. The lectins are not identical and can be distinguished on the basis of relative affinities for inhibiting sugars, isoelectric points and immunoprecipitation assays using anti-(cottonmouth lectin) serum. Images Fig. 1. Fig. 2. Fig. 4. Fig. 5. PMID:6391472
Akani, Godfrey C; Ebere, Nwabueze; Franco, Daniel; Eniang, Edem A; Petrozzi, Fabio; Politano, Edoardo; Luiselli, Luca
Venomous snakes are among the most serious health hazards for rural people in tropical regions of the world. Herein we compare the monthly activity patterns of eight venomous snake species (Elapidae and Viperidae) with those of rural people in the Niger Delta area of southern Nigeria, in order to identify the periods of highest potential risk for persons, and the human group actually at greater risk of snakebite. We documented that above-ground activity of all venomous snakes peaked in the wet season, and that high snake activity and high human activity were most highly correlated between April and August. In addition, we documented that women and teenagers were at relatively higher risk of encountering a venomous snake than adult males, despite they are less often in the field than men. Our results suggest that future programs devoted to mitigate the social and health effects of snakebites in the Niger Delta region should involve especially women and teenagers, with ad-hoc education projects if appropriate. We urge that international organizations working on social and health problems in the developing world, such as IRD, DFID, UNDP, should provide advice through specific programs targeted at especially these categories which have been highlighted in comparatively potential higher threat from snakebites than adult men.
Akani Godfrey C
Full Text Available Abstract Background Venomous snakes are among the most serious health hazards for rural people in tropical regions of the world. Herein we compare the monthly activity patterns of eight venomous snake species (Elapidae and Viperidae with those of rural people in the Niger Delta area of southern Nigeria, in order to identify the periods of highest potential risk for persons, and the human group actually at greater risk of snakebite. Results We documented that above-ground activity of all venomous snakes peaked in the wet season, and that high snake activity and high human activity were most highly correlated between April and August. In addition, we documented that women and teenagers were at relatively higher risk of encountering a venomous snake than adult males, despite they are less often in the field than men. Conclusions Our results suggest that future programs devoted to mitigate the social and health effects of snakebites in the Niger Delta region should involve especially women and teenagers, with ad-hoc education projects if appropriate. We urge that international organizations working on social and health problems in the developing world, such as IRD, DFID, UNDP, should provide advice through specific programs targeted at especially these categories which have been highlighted in comparatively potential higher threat from snakebites than adult men.
Full Text Available Objective: To evaluate the antibacterial activity of sea snake (Enhydrina schistosa venom protein against drug-resistant human pathogenic bacterial strains. Methods: The venom was collected by milking process from the live specimens of sea snake are using capillary tubes or glass plates. Venom was purified by ion exchange chromatography and it was tested for in-vitro antibacterial activity against 10 drug-resistant human pathogenic bacterial strains using the standard disc diffusion method. Results: The notable antibacterial activity was observed at 150 µg/mL concentration of purified venom and gave its minimum inhibitory concentrations values exhibited between 200-100 µg/mL against all the tested bacterial strains. The maximum zone of inhibition was observed at 16.4 mm against Salmonella boydii and the minimum activity was observed at 7.5 mm against Pseudomonas aeruginosa. After the sodium-dodecyl-sulfate-polyacrylamide gel electrophoresis there were a clear single band was detected in the gel that corresponding to purified venom protein molecular weight of 44 kDa. Conclusions: These results suggested that the sea snake venom might be a feasible source for searching potential antibiotics agents against human pathogenic diseases.
Victor Corasolla Carregari
Full Text Available Bbil-TX, a PLA2, was purified from Bothriopsis bilineata snake venom after only one chromatographic step using RP-HPLC on μ-Bondapak C-18 column. A molecular mass of 14243.8 Da was confirmed by Q-Tof Ultima API ESI/MS (TOF MS mode mass spectrometry. The partial protein sequence obtained was then submitted to BLASTp, with the search restricted to PLA2 from snakes and shows high identity values when compared to other PLA2s. PLA2 activity was presented in the presence of a synthetic substrate and showed a minimum sigmoidal behavior, reaching its maximal activity at pH 8.0 and 25–37∘C. Maximum PLA2 activity required Ca2+ and in the presence of Cd2+, Zn2+, Mn2+, and Mg2+ it was reduced in the presence or absence of Ca2+. Crotapotin from Crotalus durissus cascavella rattlesnake venom and antihemorrhagic factor DA2-II from Didelphis albiventris opossum sera under optimal conditions significantly inhibit the enzymatic activity. Bbil-TX induces myonecrosis in mice. The fraction does not show a significant cytotoxic activity in myotubes and myoblasts (C2C12. The inflammatory events induced in the serum of mice by Bbil-TX isolated from Bothriopsis bilineata snake venom were investigated. An increase in vascular permeability and in the levels of TNF-a, IL-6, and IL-1 was was induced. Since Bbil-TX exerts a stronger proinflammatory effect, the phospholipid hydrolysis may be relevant for these phenomena.
Kardong and Bradley G. Stiles. We MAMxN. 1983. Biochemical evaluation of colu- thank George Zug for access to preserved sp- brid snake phylogeny . J...Copeia 1962:291-300. phylogeny . In E. E. Buckley and N. Porges (eds.), , AND C. McCoy. 1965. Additio" bserva- Venoms, pp. 211-222. Amer. Assoc. Adv...Analyt- Biochem. 150:76-85. R. Dawson (eds.), Biology of the Reptilia , Vol. 5, Slm-t, H. M. 1950. Handbook of the Amphibians pp. 275-334. Academic Press
Casewell, Nicholas R
Tracing the evolutionary history of proteins can reveal insights into gene alterations responsible for changes in structure and function. Here, the origin of snake venom metalloproteinases was rigorously reassessed using phylogenetics and the reconstruction of ancestral sequences. Basal SVMPs are most closely related to ADAM 7, 28 and decysin-1 proteins. Reconstructing the evolutionary history of these proteins and their hypothetical ancestors reveals progressive alterations in the amino acid composition and structural characteristics of ADAMs/SVMPs through evolutionary time. Copyright © 2012 Elsevier Ltd. All rights reserved.
de Medeiros, Carlos R; Hess, Priscila L; Nicoleti, Alessandra F; Sueiro, Leticia R; Duarte, Marcelo R; de Almeida-Santos, Selma M; França, Francisco O S
We retrospectively analyzed 297 proven cases of Philodryas patagoniensis bites admitted to Hospital Vital Brazil (HVB), Butantan Institute, São Paulo, Brazil, between 1959 and 2008. Only cases in which the causative animal was brought and identified were included. Part of the snakes brought by the patients was still preserved in the collection maintained by the Laboratory of Herpetology. Of the 297 cases, in 199 it was possible to describe the gender of the snake, and seventy three (61.3%) of them were female. The length of snakes (snout-vent length) ranged from 160 to 1080 mm. In 117 snakes their state of preservation enabled the dissection and examination of their stomach contents. The stomach was empty in 106 snakes (89.1%). Most bites occurred in the seasons of spring and summer (n = 196, 66.0%) and during warmer periods of the day. The mean age of the victims was 24.1 +/- 15.1 years old and 206 (69.4%) patients were men. Around 92% of the patients sought medical care within 6 h after the bite. Both lower (n = 188, 63.3%) and upper limbs (n = 102, 34.3%) were most frequently bitten, especially the feet and hands (n = 205, 69.0%). The local clinical manifestations were pain (n = 151, 50.8%), transitory bleeding (n = 106, 35.7%), erythema (n = 47, 15.8%) and edema (n = 39, 13.1%). Ecchymosis was not observed. Only 7 (2.4%) patients reported systemic symptoms characterized by mild dizziness and 88 patients (29.6%) showed no evidence of envenoming. The whole blood clotting time was performed in 76 (25.6%) patients on admission and all of them had coagulable blood. Supportive treatment was offered to only 13.4% of patients, namely administration of antihistamines (n = 19, 6.4%) and analgesics (n = 12, 4.1%). Eight patients (2.7%) were mistreated with Bothrops antivenom before their admission to HVB. No sequels or relevant complications were observed in patients, and the prognostic was benign. Therefore, although P. patagoniensis accidents can cause mild local
Maduwage, Kalana; Silva, Anjana; O’Leary, Margaret A.; Hodgson, Wayne C.; Isbister, Geoffrey K.
In vitro antivenom efficacy studies were compared to rodent lethality studies to test two Indian snake antivenoms (VINS and BHARAT) against four Sri Lankan snakes. In vitro efficacy was tested at venom concentrations consistent with human envenoming. Efficacy was compared statistically for one batch from each manufacturer where multiple vials were available. In binding studies EC50 for all VINS antivenoms were less than BHARAT for D. russelii [553 μg/mL vs. 1371 μg/mL;p = 0.016), but were greater for VINS antivenoms compared to BHARAT for N. naja [336 μg/mL vs. 70 μg/mL;p < 0.0001]. EC50 of both antivenoms was only slighty different for E. carinatus and B. caeruleus. For procoagulant activity neutralisation, the EC50 was lower for VINS compared to BHARAT - 60 μg/mL vs. 176 μg/mL (p < 0.0001) for Russell’s viper and 357 μg/mL vs. 6906μg/mL (p < 0.0001) for Saw-scaled viper. Only VINS antivenom neutralized in vitro neurotoxicity of krait venom. Both antivenoms partially neutralized cobra and didn’t neutralize Russell’s viper neurotoxicity. Lethality studies found no statistically significant difference in ED50 values between VINS and BHARAT antivenoms. VINS antivenoms appeared superior to BHARAT at concentrations equivalent to administering 10 vials antivenom, based on binding and neutralisation studies. Lethality studies were inconsistent suggesting rodent death may not measure relevant efficacy outcomes in humans. PMID:27231196
Zajkowska, Joanna; Garkowski, Adam; Pancewicz, Sławomir
Cases of bite by common viper (Vipera berus) are rare on the territory of Poland, and the mortality after bites is less than 1%. This paper describes a case of 81-year-old patient with massive swelling, redness and soreness of the right hand, which occurred shortly after the adder bite. In this paper we present composition and mechanisms of the venom's action, clinical symptoms and treatment of poisoning after a snake bite. Based on the reported case authors draw attention to hospital treatment and indications for administration of antivenom as the only causative method of treatment.
Chuman, Y; Nobuhisa, I; Ogawa, T; Deshimaru, M; Chijiwa, T; Tan, N H; Fukumaki, Y; Shimohigashi, Y; Ducancel, F; Boulain, J C; Ménez, A; Ohno, M
In accordance with detection of a few phospholipase A2 (PLA2) isozyme genes by Southern blot analysis, only two cDNAs, named NnkPLA-I , and NnkPLA-II, encoding group I PLA2s, NnkPLA-I and NnkPLA-II, respectively, were isolated from the venom gland cDNA library of Elapinae Naja naja kaouthia of Malaysia. NnkPLA-I and NnkPLA-II showed four amino acid substitutions, all of which were brought about by single nucleotide substitution. No existence of clones encoding CM-II and CM-III, PLA2 isozymes which had been isolated from the venom of N. naja kaouthia of Thailand, in Malaysian N. naja kaouthia venom gland cDNA library was verified by dot blot hybridization analysis with particular probes. NnkPLA-I and NnkPLA-II differed from CM-II and CM-III with four and two amino acid substitutions, respectively, suggesting that their molecular evolution is regional. The comparison of NnkPLA-I, NnkPLA-II and cDNAs encoding other group I snake venom gland PLA2s indicated that the 5'- and 3'-untranslated regions are more conserved than the mature protein-coding region and that the number of nucleotide substitutions per nonsynonymous site is almost equal to that per synonymous site in the protein-coding region, suggesting that accelerated evolution has occurred in group I venom gland PLA2s possibly to acquire new physiological functions.
Comparison of the effect of Crotalus simus and Crotalus durissus ruruima venoms on the equine antibody response towards Bothrops asper venom: implications for the production of polyspecific snake antivenoms.
Dos-Santos, Maria Cristina; Arroyo, Cynthia; Solano, Sergio; Herrera, María; Villalta, Mauren; Segura, Alvaro; Estrada, Ricardo; Gutiérrez, José María; León, Guillermo
Antivenoms are preparations of immunoglobulins purified from the plasma of animals immunized with snake venoms. Depending on the number of venoms used during the immunization, antivenoms can be monospecific (if venom from a single species is used) or polyspecific (if venoms from several species are used). In turn, polyspecific antivenoms can be prepared by purifying antibodies from the plasma of animals immunized with a mixture of venoms, or by mixing antibodies purified from the plasma of animals immunized separately with single venom. The suitability of these strategies to produce polyspecific antibothropic-crotalic antivenoms was assessed using as models the venoms of Bothrops asper, Crotalus simus and Crotalus durissus ruruima. It was demonstrated that, when used as co-immunogen, C. simus and C. durissus ruruima venoms exert a deleterious effect on the antibody response towards different components of B. asper venom and in the neutralization of hemorrhagic and coagulant effect of this venom when compared with a monospecific B. asper antivenom. Polyspecific antivenoms produced by purifying immunoglobulins from the plasma of animals immunized with venom mixtures showed higher antibody titers and neutralizing capacity than those produced by mixing antibodies purified from the plasma of animals immunized separately with single venom. Thus, despite the deleterious effect of Crotalus sp venoms on the immune response against B. asper venom, the use of venom mixtures is more effective than the immunization with separate venoms for the preparation of polyspecific bothropic-crotalic antivenoms. Copyright © 2010 Elsevier Ltd. All rights reserved.
Bruna Barbosa de Sousa
Full Text Available This work reports the purification and functional characterization of BmooPAi, a platelet-aggregation-inhibiting factor from Bothrops moojeni snake venom. The toxin was purified by a combination of three chromatographic steps (ion-exchange on DEAE-Sephacel, molecular exclusion on Sephadex G-75, and affinity chromatography on HiTrap™ Heparin HP. BmooPAi was found to be a single-chain protein with an apparent molecular mass of 32 kDa on 14% SDS-PAGE, under reducing conditions. Sequencing of BmooPAi by Edman degradation revealed the amino acid sequence LGPDIVPPNELLEVM. The toxin was devoid of proteolytic, haemorrhagic, defibrinating, or coagulant activities and induced no significant oedema or hyperalgesia. BmooPAi showed a rather specific inhibitory effect on ristocetin-induced platelet aggregation in human platelet-rich plasma, whereas it had little or no effect on platelet aggregation induced by collagen and adenosine diphosphate. The results presented in this work suggest that BmooPAi is a toxin comprised of disintegrin-like and cysteine-rich domains, originating from autolysis/proteolysis of PIII SVMPs from B. moojeni snake venom. This toxin may be of medical interest because it is a platelet aggregation inhibitor, which could potentially be developed as a novel therapeutic agent to prevent and/or treat patients with thrombotic disorders.
Liesener, A.; Perchuc, Anna-Maria; Schöni, Reto; Wilmer, Marianne; Karst, U.
A multiplexed mass spectrometry based assay scheme for the simultaneous determination of five different substrate/product pairs was developed as a tool for screening of proteolytic activities in snake venom fractions from Bothrops moojeni. The assay scheme was employed in the functional
Jiang, Yu; Li, Yan; Lee, Wenhui; Xu, Xun; Zhang, Yue; Zhao, Ruoping; Zhang, Yun; Wang, Wen
...) libraries for Bungarus multicinctus and Naja atra, respectively. We sequenced about 1500 cDNA clones for each of the venom cDNA libraries and screened BAC libraries of the two snakes by blot analysis using four kinds of toxin probes; i.e...
Moussa, Ihab M; Hessan, Ashgan M; Aleisa, Abdulaziz M; Al-Arfaj, Abdullah A; Salem-Bekhit, Mounier M; AlRejai, Salim A
To prepare and evaluate the protective efficacy of immunoglobulin Y (IgY) prepared against local Saudi Cerastes cerastes snake venom. The study was conducted between October 2009 and October 2011 at the Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Kingdom of Saudi Arabia. The study designed as follow; 4 groups of 8 chickens were immunized intramuscularly with Cerastes cerastes snake venoms mixed with Freund's complete adjuvant. Three weeks later, the injections were repeated with the venoms with incomplete Freund's adjuvant. Three boosters were given with the venoms at 3 weeks intervals. The IgY was extracted by ammonium sulphate-caprylic acid method, the antibody titer were tested by enzyme linked immunosorbant assay, and the protective efficacies of the extracted immunoglobulins were performed. Immunoglobulin Y preparation extracted by ammonium sulphate-caprylic acid method showed lack of low molecular weight bands. The bands representing IgY-antibodies, which have molecular weights ranged from 180-200 KD, appeared sharp and clear. Furthermore, evaluation of the prepared protective value of IgY-antibodies revealed one ml of extracted IgY-antibodies containing 15 mg/ml anti Cerastes cerastes; specific IgY could produce 100% protection against 50 LD50. Laying hens could be used as an alternative source of polyclonal antibodies against Cerastes cerastes snake venoms due to several advantages as compared with mammals.
Full Text Available Sarafotoxins (SRTX are endothelin-like peptides extracted from the venom of snakes belonging to the Atractaspididae family. A recent in vivo study on anesthetized and ventilated animals showed that sarafotoxin-b (SRTX-b, extracted from the venom of Atractaspis engaddensis, decreases cardiac output by inducing left ventricular dysfunction while sarafotoxin-m (SRTX-m, extracted from the venom of Atractaspis microlepidota microlepidota, induces right ventricular dysfunction with increased airway pressure. The aim of the present experimental study was to compare the respiratory effects of SRTX-m and SRTX-b. Male Wistar rats were anesthetized, tracheotomized and mechanically ventilated. They received either a 1 LD50 IV bolus of SRTX-b (n = 5 or 1 LD50 of SRTX-m (n = 5. The low-frequency forced oscillation technique was used to measure respiratory impedance. Airway resistance (Raw, parenchymal damping (G and elastance (H were determined from impedance data, before and 5 min after SRTX injection. SRTX-m and SRTX-b injections induced acute hypoxia and metabolic acidosis with an increased anion gap. Both toxins markedly increased Raw, G and H, but with a much greater effect of SRTX-b on H, which may have been due to pulmonary edema in addition to bronchoconstriction. Therefore, despite their structural analogy, these two toxins exert different effects on respiratory function. These results emphasize the role of the C-terminal extension in the in vivo effect of these toxins.
Guo, Xiao-Xi; Zeng, Lin; Lee, Wen-Hui; Zhang, Yun; Jin, Yang
A 50 kDa fibrinogenolytic protease, ohagin, from the venom of Ophiophagus hannah was isolated by a combination of gel filtration, ion-exchange and heparin affinity chromatography. Ohagin specifically degraded the alpha-chain of human fibrinogen and the proteolytic activity was completely abolished by EDTA, but not by PMSF, suggesting it is a metalloproteinase. It dose-dependently inhibited platelet aggregation induced by ADP, TMVA and stejnulxin. The full sequence of ohagin was deduced by cDNA cloning and confirmed by protein sequencing and peptide mass fingerprinting. The full-length cDNA sequence of ohagin encodes an open reading frame of 611 amino acids that includes signal peptide, proprotein and mature protein comprising metalloproteinase, disintegrin-like and cysteine-rich domains, suggesting it belongs to P-III class metalloproteinase. In addition, P-III class metalloproteinases from the venom glands of Naja atra, Bungarus multicinctus and Bungarus fasciatus were also cloned in this study. Sequence analysis and phylogenetic analysis indicated that metalloproteinases from elapid snake venoms form a new subgroup of P-III SVMPs.
Hayashi, Y; Tanaka, H; Wada, Y; Mishima, S
For the purpose of preventing invasion of Trimeresurus flavoviridis, Habu, the venomous snake, the effect of an electric fence made of hollow tile blocks or polyethylene net was examined in 3 villages on Amamioshima and Tokunoshima islands in the southernmost area of Japan. The electric pulses were supplied by a pulse maker at 0.75 sec. intervals with 480 mA, 0.13 m coulombs at a load of 500 ohms and estimated peak of 8 to 10 kV. The anode from a pulse maker was connected to a stainless steel plate or a metal string woven in a vinyl rope on the fence and the cathode was grounded. The power to the pulse maker was generated by silicon solar cells, stored in a car battery and regulated by an electric eye switch to activate it at night. The necessary height of the fence to prevent Habu from slithering over the fence was experimentally determined to be 60 cm. In 3 villages, 6.75 ha were enclosed with 1000 m fence, 13.7 ha with 2100 m and 23.8 ha with 2500 m, respectively. The effect of the electric fence was remarkable as determined by the annual monitoring of the number of snakes sighted by people and the captivity rate in box traps inside the fence. The number of snakes found annually in Tean Village was 10 before construction and 5, 4, 5 after construction; 119 before construction 55, 20, 20 after construction at Tete; and 109 and 82 before construction and 15 and 11 after construction at Todoroki. The snakes were observed to aggregate outside the fence. The net barrier could be constructed at any topographical conditions with less expense. The effect was further pronounced when snakes were removed by box trap and other methods from inside the fenced area.
Francis Barbosa Ferreira
Full Text Available In this work, we describe the molecular cloning and pharmacological properties of an acidic phospholipase A2 (PLA2 isolated from Bothrops pauloensis snake venom. This enzyme, denominated BpPLA2-TXI, was purified by four chromatographic steps and represents 2.4% of the total snake venom protein content. BpPLA2-TXI is a monomeric protein with a molecular mass of 13.6 kDa, as demonstrated by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF analysis and its theoretical isoelectric point was 4.98. BpPLA2-TXI was catalytically active and showed some pharmacological effects such as inhibition of platelet aggregation induced by collagen or ADP and also induced edema and myotoxicity. BpPLA2-TXI displayed low cytotoxicity on TG-180 (CCRF S 180 II and Ovarian Carcinoma (OVCAR-3, whereas no cytotoxicity was found in regard to MEF (Mouse Embryonic Fibroblast and Sarcoma 180 (TIB-66. The N-terminal sequence of forty-eight amino acid residues was determined by Edman degradation. In addition, the complete primary structure of 122 amino acids was deduced by cDNA from the total RNA of the venom gland using specific primers, and it was significantly similar to other acidic D49 PLA2s. The phylogenetic analyses showed that BpPLA2-TXI forms a group with other acidic D49 PLA2s from the gender Bothrops, which are characterized by a catalytic activity associated with anti-platelet effects.
da Silva, Marcos L; Marcussi, Silvana; Fernandes, Renata S; Pereira, Paulo S; Januário, Ana Helena; França, Suzelei C; Da Silva, Saulo L; Soares, Andreimar M; Lourenço, Miriam V
Sapindus saponaria L. (Sapindaceae) bark, root, and fruits are used as sedatives and to treat gastric ulcer and also demonstrate diuretic and expectorant effects. The anti-snake venom properties of callus of S. saponaria are investigated here for the first time. In vitro cultivated callus of Sapindus saponaria were lyophilized, and the extracts were prepared with different solvents, before submitting to phytochemical studies and evaluation of the anti-ophidian activity. Crude extracts were fractionated by liquid-liquid partition and the fractions were monitored by thin layer chromatography (TLC). Subsequently, anti-ophidian activities were analyzed toward Bothrops jararacussu Lacerda (Viperidae), B. moojeni Hoge (Viperidae), B. alternates Duméril (Viperidea) and Crotalus durissus terrificus Lineu (Viperidae) venoms and isolated myotoxins and phospholipase A(2) (PLA(2)). Fractions A1, A2 and the extract in MeOH:H(2)O (9:1) significantly inhibited the toxic and pharmacological activities induced by snake venoms and toxins, when compared to other extracts and fractions. The lethal, clotting, phospholipase, edema-inducing, hemorrhagic and myotoxic activities were partially inhibited by the different extracts and fractions. TLC profiles of the crude extracts (B and C) and fractions (A1 and A2) showed β-sitosterol and stigmasterol as their main compounds. Stigmasterol exhibited inhibitory effects on enzymatic and myotoxic activities of PLA(2). Sapindus saponaria extracts and fractions presented anti-ophidian activity and could be used as an adjuvant to serum therapy or for its supplementation, and in addition, as a rich source of potential inhibitors of enzymes involved in several pathophysiological human and animal diseases.
Margres, Mark J; McGivern, James J; Seavy, Margaret; Wray, Kenneth P; Facente, Jack; Rokyta, Darin R
Selection is predicted to drive diversification within species and lead to local adaptation, but understanding the mechanistic details underlying this process and thus the genetic basis of adaptive evolution requires the mapping of genotype to phenotype. Venom is complex and involves many genes, but the specialization of the venom gland toward toxin production allows specific transcripts to be correlated with specific toxic proteins, establishing a direct link from genotype to phenotype. To determine the extent of expression variation and identify the processes driving patterns of phenotypic diversity, we constructed genotype-phenotype maps and compared range-wide toxin-protein expression variation for two species of snake with nearly identical ranges: the eastern diamondback rattlesnake (Crotalus adamanteus) and the eastern coral snake (Micrurus fulvius). We detected significant expression variation in C. adamanteus, identified the specific loci associated with population differentiation, and found that loci expressed at all levels contributed to this divergence. Contrary to expectations, we found no expression variation in M. fulvius, suggesting that M. fulvius populations are not locally adapted. Our results not only linked expression variation at specific loci to divergence in a polygenic, complex trait but also have extensive conservation and biomedical implications. C. adamanteus is currently a candidate for federal listing under the Endangered Species Act, and the loss of any major population would result in the irrevocable loss of a unique venom phenotype. The lack of variation in M. fulvius has significant biomedical application because our data will assist in the development of effective antivenom for this species. Copyright © 2015 by the Genetics Society of America.
Lecht, Shimon; Chiaverelli, Rachel A; Gerstenhaber, Jonathan; Calvete, Juan J; Lazarovici, Philip; Casewell, Nicholas R; Harrison, Robert; Lelkes, Peter I; Marcinkiewicz, Cezary
Cysteine-rich secretory protein (CRISP) is present in majority of vertebrate including human. The physiological role of this protein is not characterized. We report that a CRISP isolated from Echis carinatus sochureki venom (ES-CRISP) inhibits angiogenesis. The anti-angiogenic activity of purified ES-CRISP from snake venom was investigated in vitro using endothelial cells assays such as proliferation, migration and tube formation in Matrigel, as well as in vivo in quail embryonic CAM system. The modulatory effect of ES-CRISP on the expression of major angiogenesis factors and activation of angiogenesis pathways was tested by qRT-PCR and Western blot. The amino acid sequence of ES-CRISP was found highly similar to other members of this snake venom protein family, and shares over 50% identity with human CRISP-3. ES-CRISP supported adhesion to endothelial cells, although it was also internalized into the cytoplasm in a granule-like manner. It blocked EC proliferation, migration and tube formation in Matrigel. In the embryonic quail CAM system, ES-CRISP abolished neovascularization process induced by exogenous growth factors (bFGF, vpVEGF) and by developing gliomas. CRISP modulates the expression of several factors at the mRNA level, which were characterized as regulators of angiogenesis and blocked activation of MAPK Erk1/2 induced by VEGF. ES-CRISP was characterized as a negative regulator of the angiogenesis, by direct interaction with endothelial cells. The presented work may lead to the development of novel angiostatic therapy, as well as contribute to the identification of the physiological relevance of this functionally uncharacterized protein. Copyright © 2015 Elsevier B.V. All rights reserved.
Rey-Suárez, Paola; Núñez, Vitelbina; Gutiérrez, José María; Lomonte, Bruno
Venoms of the redtail coral snake Micrurus mipartitus from Colombia and Costa Rica were analyzed by "venomics", a proteomic strategy to determine their composition. Proteins were separated by RP-HPLC, followed by SDS-PAGE, in-gel tryptic digestion, identification by MALDI or ESI tandem mass spectrometry, and assignment to known protein families by similarity. These analyses were complemented with a characterization of venom activities in vitro and in vivo. Proteins belonging to seven families were found in Colombian M. mipartitus venom, including abundant three-finger toxins (3FTx; ~60% of total proteins) and phospholipases A(2) (PLA(2); ~30%), with the remaining ~10% distributed among l-amino acid oxidase, P-III metalloproteinase, Kunitz-type inhibitor, serine proteinase, and C-type lectin-like families. The venoms of two M. mipartitus specimens from Costa Rica, also referred to as M. multifasciatus in some taxonomic classifications, were also analyzed. Both samples were highly similar to each other, and partially resembled the chromatographic and identity profiles of M. mipartitus from Colombia, although presenting a markedly higher proportion of 3FTxs (~83.0%) in relation to PLA(2)s (~8.2%), and a small amount of acetylcholinesterase, not detected in the venom from Colombia. An equine antivenom against the Central American coral snake, M. nigrocinctus, did not recognize venom components of M. mipartitus from Colombia or Costa Rica by enzyme-immunoassay. Four major components of Colombian M. mipartitus venom were isolated and partially characterized. Venomics of Micrurus species may provide a valuable platform for the rational design of immunizing cocktails to obtain polyspecific antivenoms for this highly diverse group of American elapids. Copyright © 2011 Elsevier B.V. All rights reserved.
Queiroz, Rodrigo Guimaraes
Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)
Mladic, Marija; de Waal, Tessa; Burggraaff, Lindsey; Slagboom, Julien; Somsen, Govert W; Niessen, Wilfried M A; Manjunatha Kini, R; Kool, Jeroen
This study presents an analytical method for the screening of snake venoms for inhibitors of the angiotensin-converting enzyme (ACE) and a strategy for their rapid identification. The method is based on an at-line nanofractionation approach, which combines liquid chromatography (LC), mass spectrometry (MS), and pharmacology in one platform. After initial LC separation of a crude venom, a post-column flow split is introduced enabling parallel MS identification and high-resolution fractionation onto 384-well plates. The plates are subsequently freeze-dried and used in a fluorescence-based ACE activity assay to determine the ability of the nanofractions to inhibit ACE activity. Once the bioactive wells are identified, the parallel MS data reveals the masses corresponding to the activities found. Narrowing down of possible bioactive candidates is provided by comparison of bioactivity profiles after reversed-phase liquid chromatography (RPLC) and after hydrophilic interaction chromatography (HILIC) of a crude venom. Additional nanoLC-MS/MS analysis is performed on the content of the bioactive nanofractions to determine peptide sequences. The method described was optimized, evaluated, and successfully applied for screening of 30 snake venoms for the presence of ACE inhibitors. As a result, two new bioactive peptides were identified: pELWPRPHVPP in Crotalus viridis viridis venom with IC 50 = 1.1 μM and pEWPPWPPRPPIPP in Cerastes cerastes cerastes venom with IC 50 = 3.5 μM. The identified peptides possess a high sequence similarity to other bradykinin-potentiating peptides (BPPs), which are known ACE inhibitors found in snake venoms.
Nalbantsoy, Ayse; Erel, Sura Baykan; Köksal, Cinel; Göçmen, Bayram; Yıldız, Mehmet Zülfü; Karabay Yavaşoğlu, Nefise Ülkü
The present study was conducted to explore the characterization of Montivipera xanthina crude venom partially by in vitro and in vivo and the anti-snake venom activities of Artemisia absinthium L. in comparison with carrageenan-induced acute inflammation model in rats. The LD50 value was estimated as 8.78 mg/kg within 24 h by different venom doses administrated intraperitoneally in mice. The IC50 value was 0.43 ± 0.18 μg/ml after 48 h treatment while the calculated value was 0.73 ± 0.10 μg/ml for the culture media totally refreshed after 2 h treatment with venom. Wistar rats were treated intraperitoneally with A. absinthium extract, 30 min before venom or carrageenan was injected subplantarly into the left hind paw. Intraperitoneal administration of 25 and 50 mg/kg extract was inhibited venom induced paw swelling at 0.5, 1, 2 and 3 h (p absinthium was described. Copyright © 2013 Elsevier Ltd. All rights reserved.
Full Text Available Abstract Background The genus Bothrops is widespread throughout Central and South America and is the principal cause of snakebite in these regions. Transcriptomic and proteomic studies have examined the venom composition of several species in this genus, but many others remain to be studied. In this work, we used a transcriptomic approach to examine the venom gland genes of Bothrops alternatus, a clinically important species found in southeastern and southern Brazil, Uruguay, northern Argentina and eastern Paraguay. Results A cDNA library of 5,350 expressed sequence tags (ESTs was produced and assembled into 838 contigs and 4512 singletons. BLAST searches of relevant databases showed 30% hits and 70% no-hits, with toxin-related transcripts accounting for 23% and 78% of the total transcripts and hits, respectively. Gene ontology analysis identified non-toxin genes related to general metabolism, transcription and translation, processing and sorting, (polypeptide degradation, structural functions and cell regulation. The major groups of toxin transcripts identified were metalloproteinases (81%, bradykinin-potentiating peptides/C-type natriuretic peptides (8.8%, phospholipases A2 (5.6%, serine proteinases (1.9% and C-type lectins (1.5%. Metalloproteinases were almost exclusively type PIII proteins, with few type PII and no type PI proteins. Phospholipases A2 were essentially acidic; no basic PLA2 were detected. Minor toxin transcripts were related to L-amino acid oxidase, cysteine-rich secretory proteins, dipeptidylpeptidase IV, hyaluronidase, three-finger toxins and ohanin. Two non-toxic proteins, thioredoxin and double-specificity phosphatase Dusp6, showed high sequence identity to similar proteins from other snakes. In addition to the above features, single-nucleotide polymorphisms, microsatellites, transposable elements and inverted repeats that could contribute to toxin diversity were observed. Conclusions Bothrops alternatus venom gland
Leanpolchareanchai, Jiraporn; Pithayanukul, Pimolpan; Bavovada, Rapepol; Saparpakorn, Patchreenart
The ethanolic extract from seed kernels of Thai mango (MSKE) (Mangifera indica L. cv. 'Fahlun') (Anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase A(2) (PLA(2)), hyaluronidase and L-amino acid oxidase (LAAO) of Calloselasma rhodostoma (CR) and Naja naja kaouthia (NK)venoms by in vitro tests. The anti-hemorrhagic and anti-dermonecrotic activities of MSKE against both venoms were clearly supported by in vivo tests. Molecular docking studies indicated that the phenolic molecules of the MSKE could selectively bind to the active sites or their proximity, or modify conserved residues that are critical for the catalysis of PLA(2), and selectively bind to the LAAO binding pocket of both CR and NK venoms and thereby inhibit their enzymatic activities. The results imply a potential use of MSKE against snake venoms.
Background Advances in DNA sequencing and proteomics have facilitated quantitative comparisons of snake venom composition. Most studies have employed one approach or the other. Here, both Illumina cDNA sequencing and LC/MS were used to compare the transcriptomes and proteomes of two pit vipers, Protobothrops flavoviridis and Ovophis okinavensis, which differ greatly in their biology. Results Sequencing of venom gland cDNA produced 104,830 transcripts. The Protobothrops transcriptome contained transcripts for 103 venom-related proteins, while the Ovophis transcriptome contained 95. In both, transcript abundances spanned six orders of magnitude. Mass spectrometry identified peptides from 100% of transcripts that occurred at higher than contaminant (e.g. human keratin) levels, including a number of proteins never before sequenced from snakes. These transcriptomes reveal fundamentally different envenomation strategies. Adult Protobothrops venom promotes hemorrhage, hypotension, incoagulable blood, and prey digestion, consistent with mammalian predation. Ovophis venom composition is less readily interpreted, owing to insufficient pharmacological data for venom serine and metalloproteases, which comprise more than 97.3% of Ovophis transcripts, but only 38.0% of Protobothrops transcripts. Ovophis venom apparently represents a hybrid strategy optimized for frogs and small mammals. Conclusions This study illustrates the power of cDNA sequencing combined with MS profiling. The former quantifies transcript composition, allowing detection of novel proteins, but cannot indicate which proteins are actually secreted, as does MS. We show, for the first time, that transcript and peptide abundances are correlated. This means that MS can be used for quantitative, non-invasive venom profiling, which will be beneficial for studies of endangered species. PMID:24224955
Salazar, Ana M; Vivas, Jeilyn; Sánchez, Elda E; Rodríguez-Acosta, Alexis; Ibarra, Carlos; Gil, Amparo; Carvajal, Zoila; Girón, María E; Estrella, Amalid; Navarrete, Luis F; Guerrero, Belsy
The coral snake Micrurus tener tener (Mtt) from the Elapidae family inhabits the southwestern United States and produces severe cases of envenomations. Although the majority of Mtt venom components are neurotoxins and phospholipase A₂s, this study demonstrated, by SDS-PAGE and molecular exclusion chromatography (MEC), that these venoms also contain high-molecular-weight proteins between 50 and 150 kDa that target the hemostatic system. The biological aspects of other Micrurus venoms were also studied, such as the LD₅₀s of Micrurus isozonus (from 0.52 to 0.61 mg/kg). A pool from these venoms presented a LD₅₀ of 0.57 mg/kg, Micrurus f. fulvius (Mff) and Mtt had LD₅₀s of 0.32 and 0.78 mg/kg, respectively. These venoms contained fibrino(geno)lytic activity, they inhibited platelet aggregation, as well as factor Xa and/or plasmin-like activities. M. isozonus venoms from different Venezuelan geographical regions inhibited ADP-induced platelet aggregation (from 50 to 68%). Micrurus tener tener venom from the United States was the most active with a 95.2% inhibitory effect. This venom showed thrombin-like activity on fibrinogen and human plasma. Fractions of Mtt showed fibrino(geno)lytic activity and inhibition on plasmin amidolytic activity. Several fractions degraded the fibrinogen Aα chains, and fractions F2 and F7 completely degraded both fibrinogen Aα and Bβ chains. To our knowledge, this is the first report on thrombin-like and fibrino(geno)lytic activity and plasmin or factor Xa inhibitors described in Micrurus venoms. Further purification and characterization of these Micrurus venom components could be of therapeutic use in the treatment of hemostatic disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.
de Oliveira, Ursula Castro; Assui, Alessandra; da Silva, Alvaro Rossan de Brandão Prieto; de Oliveira, Jane Silveira; Ho, Paulo Lee
During the cloning of abundant cDNAs expressed in the Micrurus corallinus coral snake venom gland, several putative toxins, including a phospholipase A2 homologue cDNA (clone V2), were identified. The V2 cDNA clone codes for a potential coral snake toxin with a signal peptide of 27 amino acid residues plus a predicted mature protein with 119 amino acid residues. The deduced protein is highly similar to known phospholipases A2, with seven deduced S-S bridges at the same conserved positions. This protein was expressed in Escherichia coli as a His-tagged protein that allowed the rapid purification of the recombinant protein. This protein was used to generate antibodies, which recognized the recombinant protein in Western blot. This antiserum was used to screen a large number of venoms, showing a ubiquitous distribution of immunorelated proteins in all elapidic venoms but not in the viperidic Bothrops jararaca venom. This is the first description of a complete primary structure of a phospholipase A2 homologue deduced by cDNA cloning from a coral snake.
Camacho, Erika; Sanz, Libia; Escalante, Teresa; Pérez, Alicia; Villalta, Fabián; Lomonte, Bruno; Neves-Ferreira, Ana Gisele C; Feoli, Andrés; Calvete, Juan J; Gutiérrez, José María; Rucavado, Alexandra
Snake venom metalloproteinases (SVMPs) play key biological roles in prey immobilization and digestion. The majority of these activities depend on the hydrolysis of relevant protein substrates in the tissues. Hereby, we describe several isoforms and a cDNA clone sequence, corresponding to PII SVMP homologues from the venom of the Central American pit viper Bothriechis lateralis, which have modifications in the residues of the canonical sequence of the zinc-binding motif HEXXHXXGXXH. As a consequence, the proteolytic activity of the isolated proteins was undetectable when tested on azocasein and gelatin. These PII isoforms comprise metalloproteinase and disintegrin domains in the mature protein, thus belonging to the subclass PIIb of SVMPs. PII SVMP homologues were devoid of hemorrhagic and in vitro coagulant activities, effects attributed to the enzymatic activity of SVMPs, but induced a mild edema. One of the isoforms presents the characteristic RGD sequence in the disintegrin domain and inhibits ADP- and collagen-induced platelet aggregation. Catalytically-inactive SVMP homologues may have been hitherto missed in the characterization of snake venoms. The presence of such enzymatically-inactive homologues in snake venoms and their possible toxic and adaptive roles deserve further investigation.
Vergara, Irene; Pedraza-Escalona, Martha; Paniagua, Dayanira; Restano-Cassulini, Rita; Zamudio, Fernando; Batista, Cesar V F; Possani, Lourival D; Alagón, Alejandro
Here we show for the first time that the venom from an elapid (Micrurus fulvius) contains three finger toxin (3FTxs) peptides with low toxicity but high content of lethal phospholipases A2 (PLA2). The intravenous venom LD50 in mice was 0.3μg/g. Fractionation on a C18 column yielded 22 fractions; in terms of abundance, 58.3% of them were components of 13-14kDa and 24.9% were molecules of 6-7kDa. Two fractions with PLA2 activity represented 33.4% of the whole venom and were the most lethal fractions. Fractions with low molecular mass (coral snake venoms from South America, M. fulvius has minor amounts of low molecular mass components, but high content of PLA2, which is responsible for the venom lethality of this species. The results reported here contribute to better understanding of envenomation development and to improve antivenom design and production. These findings break from the paradigm that neurotoxicity caused by Micrurus venoms is mainly attributable to 3FTx neurotoxins and encourage future studies on Micrurus evolution and venom specialization. This article is part of a Special Issue entitled Non-model organisms. Copyright © 2014 Elsevier B.V. All rights reserved.
Eduardo Coriolano de Oliveira
Full Text Available Snake venoms are composed of a complex mixture of active proteins that induce toxic effects, such as edema, hemorrhage, and death. Lachesis muta has the highest lethality indices in Brazil. In most cases, antivenom fails to neutralize local effects, leading to disabilities in victims. Thus, alternative treatments are under investigation, and plant extracts are promising candidates. The objective of this work was to investigate the ability of crude extracts, fractions, or isolated products of Erythroxylum ovalifolium and Erythroxylum subsessile to neutralize some toxic effects of L. muta venom. All samples were mixed with L. muta venom, then in vivo (hemorrhage and edema and in vitro (proteolysis, coagulation, and hemolysis assays were performed. Overall, crude extracts or fractions of Erythroxylum spp. inhibited (20%–100% toxic effects of the venom, but products achieved an inhibition of 4%–30%. However, when venom was injected into mice before the plant extracts, hemorrhage and edema were not inhibited by the samples. On the other hand, an inhibition of 5%–40% was obtained when extracts or products were given before venom injection. These results indicate that the extracts or products of Erythroxylum spp. could be a promising source of molecules able to treat local toxic effects of envenomation by L. muta venom, aiding in the development of new strategies for antivenom treatment.
Endo, T; Oya, M; Joubert, F J; Hayashi, K; Miyazawa, T
Proton nuclear magnetic resonance (NMR) spectra have been recorded of various neurotoxins from snake venoms. pH dependence of the chemical shifts and resonance intensity has been followed for the functionally essential Trp-29. The indole N-1 proton of Trp-29 in alpha-bungarotoxin, toxin B, and cobrotoxin exhibits appreciably large upfield shifts as the pH is lowered and the suppressed exchange with the solvent hydrogen at pH 3-4, but not in Naja haje annulifera 10 where Asp-31 is replaced with Gly-31. This observation strongly suggests the presence of a hydrogen bond between Trp-29 and Asp-31 that is probably important in stabilizing the arrangement of the functionally essential residues to form a distinct binding region for the receptor.
Cini, C; Foppoli, C; De Marco, C
Thialysine is oxidatively deaminated by snake venom L-aminoacid oxidase at alkaline pH. The oxygen consumption curves show a characteristic diphasic course: the quick uptake of half a mole of oxygen per mole of substrate, in aggreement with a typical oxidative deamination, is followed by a slow extra oxygen consumption. The first product of the reaction is the corresponding alpha-oxo-epsilon-amino acid, which spontaneously cyclizes to the internal Schiff base 5-6-dihydro-delta 3,1,4-thiazin-3-carboxylic acid (TZCA). This latter has been identified by its UV absorption spectrum, by some chemical reactions, by paper chromatography, and by the production of cystamine and glyoxylic acid after prolonged oxidation of thialysine followed by acid hydrolysis. The possibility of an alpha-beta elimination reaction giving rise to cysteamine from thialysine, coupled to the oxidative deamination, has been excluded.
Sunagar, Kartik; Jackson, Timothy N. W.; Undheim, Eivind A. B.; Ali, Syed. A.; Antunes, Agostinho; Fry, Bryan G.
Three-finger toxins (3FTx) represent one of the most abundantly secreted and potently toxic components of colubrid (Colubridae), elapid (Elapidae) and psammophid (Psammophiinae subfamily of the Lamprophidae) snake venom arsenal. Despite their conserved structural similarity, they perform a diversity of biological functions. Although they are theorised to undergo adaptive evolution, the underlying diversification mechanisms remain elusive. Here, we report the molecular evolution of different 3FTx functional forms and show that positively selected point mutations have driven the rapid evolution and diversification of 3FTx. These diversification events not only correlate with the evolution of advanced venom delivery systems (VDS) in Caenophidia, but in particular the explosive diversification of the clade subsequent to the evolution of a high pressure, hollow-fanged VDS in elapids, highlighting the significant role of these toxins in the evolution of advanced snakes. We show that Type I, II and III α-neurotoxins have evolved with extreme rapidity under the influence of positive selection. We also show that novel Oxyuranus/Pseudonaja Type II forms lacking the apotypic loop-2 stabilising cysteine doublet characteristic of Type II forms are not phylogenetically basal in relation to other Type IIs as previously thought, but are the result of secondary loss of these apotypic cysteines on at least three separate occasions. Not all 3FTxs have evolved rapidly: κ-neurotoxins, which form non-covalently associated heterodimers, have experienced a relatively weaker influence of diversifying selection; while cytotoxic 3FTx, with their functional sites, dispersed over 40% of the molecular surface, have been extremely constrained by negative selection. We show that the a previous theory of 3FTx molecular evolution (termed ASSET) is evolutionarily implausible and cannot account for the considerable variation observed in very short segments of 3FTx. Instead, we propose a theory of
Oliveira, D A; Harasawa, C; Seibert, C S; Casais e Silva, L L; Pimenta, D C; Lebrun, I; Sandoval, M R L
The present study evaluated four phospholipase A2 (PLA2) (Mlx-8, Mlx-9, Mlx-11 and Mlx-12) isolated from Micrurus lemniscatus snake venom (Elapidae). The effects of intrahippocampal administration of these toxins have been determined on behavior, electroencephalography, and neuronal degeneration in rats. These four PLA2 toxins induced motor and EEG alterations in a dose-dependent manner. Behavioral convulsions were characterized by clonic movements and were often accompanied by EEG alterations. Mlx toxins were convulsive but weakly epileptogenic, since low rates of seizure discharges were observed in EEG records. Neuronal injury seemed to depend on the dose of the toxin used. The highest doses of toxins caused severe intoxication and death of some animals. The injury of hippocampal cells was characterized by massive neuronal loss and hippocampal gliosis. A high occurrence of compulsive scratching was observed. Moreover, the onset of seizures induced by Mlx toxins was markedly delayed. The similarities between the effects of Mlx PLA2s and those isolated from other Elapidae snakes venoms suggest that their toxicity are probably due to their specific binding to neuronal membranes and to the catalysis of phospholipid hydrolysis, producing lysophospholipids and fatty acids. These compounds likely disturb the membrane conformation, causing a marked increase in the release of neurotransmitters and concurrent inhibition of vesicle fission and recycling. These toxins can be a useful tool to investigate properties of endogenous secretory PLA2s and therefore may be important both to study mechanisms involved in neurotransmitter release at nerve terminals and to explain the convulsive properties of PLA2s toxins.
Tang, Song-Shan; Wang, Xiao-Hua; Zhang, Juan-Hui; Tang, Bo-Shan; Qian, Li; Li, Pei-Ying; Luo, Lie-Wei
A number of snake venom thrombin-like enzymes (TLEs) have already been characterized. Some TLEs play significant roles in vessel injury hemostasis. A novel TLE (Agacutase) was purified from Deinagkistrodon acutus snake venom by the means of Sephadex G-75, DEAE-Sepharose FF, and Sephadex G-25 column chromatography. Structural analysis indicated that Agacutase is a single-chain glycoprotein with a molecular mass of 31,084 Da, isoelectric point of 4.38, optimal activity at 37 °C and pH 6.6, sugar content of 7.6%. Its N-terminal 44 amino acid sequence was determined to be VIGGNECDTNEHRFLAAFFTSRPWIFQCAGTLIHEEWVLAAAHC, showing maximum identity of 80% with that of Dav-X protease. The Agacutase-induced clotting activity was not influenced by heparin, hirudin, or Dextran 40, but activated by Ca(2+) and inhibited by PMSF or lactose, which suggests that Agacutase is a serine protease and the coagulation activity is independent of Thrombin. Agacutase with arginine esterase activity specifically cleaves the α-chain of fibrinogen. Agacutase iv (0.03-0.12 U/kg) shortened 16-68% of the rabbit blood clotting time. No significant influence was indicated on platelet, Factor II and XIII, or fibrinolytic system. It converts fibrinogen into the soluble fibrin that accelerates hemostasis at wound. Pharmacological comparison showed the hemostatic effect of Agacutase lasted 24h while Reptilase did 8h. Its maximum tolerated, abnormal toxicity, allergic, and hemorrhagin doses were 80 U/kg, 1 U, 2 U, and 50 U, respectively, whereas those of Reptilase or Agacutin were 35 U/kg, 0.25 U, 0.25 U, and 0.2 U, respectively. The results indicated that Agacutase may be a predominant coagulant. Copyright © 2013 Elsevier B.V. All rights reserved.
Lopes da Silva, L. F. F.; Zamboni, C. B.; Bahovschi, V.; Metairon, S.; Suzuki, M. F.; Sant'Anna, O. A.; Rizzutto, M. A.
In this work, mice genetically modified [HIII line] were immunized against different Bothrops snake venoms to produce anti-Bothrops serum (antivenom). The Neutron Activation Analysis (NAA) and Energy Dispersive X-Ray Fluorescence (EDXRF) techniques were used to evaluate Ca and Fe concentrations in blood of these immunized mice in order to establish a potential correlation between both phenotypes: antibody response and blood constituents after Bothrops venom administration. The results were compared with the control group (mice not immunized) and with human being estimative. These data are important for clinical screening of patients submitted to immunological therapy as well as the understanding of the envenoming mechanisms.
Ferreira, Rui Seabra; de Barros, Luciana Curtolo; Abbade, Luciana Patrícia Fernandes; Barraviera, Silvia Regina Catharino Sartori; Silvares, Maria Regina Cavariani; de Pontes, Leticia Gomes; Dos Santos, Lucilene Delazari; Barraviera, Benedito
Hemostatic and adhesive agents date back to World War II, when homologous fibrin sealant came onto scene. Considering that infectious diseases can be transmitted via human blood, a new heterologous fibrin sealant was standardized in the 1990s. Its components were a serine protease (a thrombin-like enzyme) extracted from the venom of Crotalus durissus terrificus snakes and a fibrinogen-rich cryoprecipitate extracted from the blood of Bubalus bubalis buffaloes. This new bioproduct has been used as a coagulant, sealant, adhesive and recently as a candidate scaffold for mesenchymal stem cells and bone and cartilage repair. This review discusses the composition of a new heterologous fibrin sealant, and cites published articles related to its preclinical applications aiming at repairing nervous system traumas and regenerating bone marrow. Finally, we present an innovative safety trial I/II that found the product to be a safe and clinically promising candidate for treating chronic venous ulcers. A multicenter clinical trial, phase II/III, with a larger number of participants will be performed to prove the efficacy of an innovative biopharmaceutical product derived from animal venom.
de Souza, Raoni Almeida; Díaz, Natalia; Nagem, Ronaldo Alves Pinto; Ferreira, Rafaela Salgado; Suárez, Dimas
Snake venom metalloproteinases are important toxins that play fundamental roles during envenomation. They share a structurally similar catalytic domain, but with diverse hemorrhagic capabilities. To understand the structural basis for this difference, we build and compare two dynamical models, one for the hemorrhagic atroxlysin-I from Bothrops atrox and the other for the non-hemorraghic leucurolysin-a from Bothrops leucurus. The analysis of the extended molecular dynamics simulations shows some changes in the local structure, flexibility and surface determinants that can contribute to explain the different hemorrhagic activity of the two enzymes. In agreement with previous results, the long Ω-loop (from residue 149 to 177) has a larger mobility in the hemorrhagic protein. In addition, we find some potentially-relevant differences at the base of the S1' pocket, what may be interesting for the structure-based design of new anti-venom agents. However, the sharpest differences in the computational models of atroxlysin-I and leucurolysin-a are observed in the surface electrostatic potential around the active site region, suggesting thus that the hemorrhagic versus non-hemorrhagic activity is probably determined by protein surface determinants.
Snake venom metalloproteinases (SVMPs) induces local and systemic effects on patients suffering from snakebite, degrading extracellular matrix (ECM) proteins such as collagen, gelatin, elastin, laminin, fibronectin, nidogen (entactin), and thrombospondin that cause local hemorrhage and tissue damage. They cleave or activate coagulation factors such as fibrinogen, fibrin, prothrombin, factor V, factor IX, factor X and protein C that bring about systemic coagulopathy. SVMPs and their truncated forms cleave or interfere with platelet adhesive proteins such as vWF, fibrinogen and collagen, and cleave or interfere with platelet receptors such as GPVI, alpha2beta1, GPIb, GPIX, and GPIIbIIIa that result in platelet aggregation defect. SVMPs induce cancer cell line to form morphological changes and apoptosis in vitro concordant with skin necrosis after snakebite in some cases. These local effects caused by SVMPs have no certain treatments, even with commercial anti-venom. SVMPs researches are focusing on their inhibitors, measurement and replacement of blood coagulation factor defects, or anti-cancer drug.
Takeda, Soichi; Takeya, Hiroyuki; Iwanaga, Sadaaki
Metalloproteinases are among the most abundant toxins in many Viperidae venoms. Snake venom metalloproteinases (SVMPs) are the primary factors responsible for hemorrhage and may also interfere with the hemostatic system, thus facilitating loss of blood from the vasculature of the prey. SVMPs are phylogenetically most closely related to mammalian ADAM (a disintegrin and metalloproteinase) and ADAMTS (ADAM with thrombospondin type-1 motif) family of proteins and, together with them, constitute the M12B clan of metalloendopeptidases. Large SVMPs, referred to as the P-III class of SVMPs, have a modular architecture with multiple non-catalytic domains. The P-III SVMPs are characterized by higher hemorrhagic and more diverse biological activities than the P-I class of SVMPs, which only have a catalytic domain. Recent crystallographic studies of P-III SVMPs and their mammalian counterparts shed new light on structure-function properties of this class of enzymes. The present review will highlight these structures, particularly the non-catalytic ancillary domains of P-III SVMPs and ADAMs that may target the enzymes to specific substrates. This article is part of a Special Issue entitled: Proteolysis 50years after the discovery of lysosome. Copyright © 2011 Elsevier B.V. All rights reserved.
Ali, Syed A; Yang, Daryl C; Jackson, Timothy N W; Undheim, Eivind A B; Koludarov, Ivan; Wood, Kelly; Jones, Alun; Hodgson, Wayne C; McCarthy, Sean; Ruder, Tim; Fry, Bryan G
Intra- and interspecific variation in venom composition has been shown to have a major effect upon the efficacy of antivenoms. Due to the absence of domestically produced antivenoms, Pakistan is wholly reliant upon antivenoms produced in other countries, such as India. However, the efficacy of these antivenoms in neutralising the venoms of Pakistani snakes has not been ascertained. This is symptomatic of the general state of toxicological research in this country, which has a myriad of highly toxic and medically important venomous animals. Thus, there is a dire need for knowledge regarding the fundamental proteomics of these venoms and applied knowledge of the relative efficacy of foreign antivenoms. Here we present the results of our proteomic research on two medically important snakes of Pakistan: Bungarus sindanus and Naja naja. Indian Polyvalent Antivenom (Bharat Serums and Vaccines Ltd), which is currently marketed for use in Pakistan, was completely ineffective against either Pakistani species. In addition to the expected pre- and post-synaptic neurotoxic activity, the venom of the Pakistan population of N. naja was shown to be quite divergent from other populations of this species in being potently myotoxic. These results highlight the importance of studying divergent species and isolated populations, where the same data not only elucidates clinical problems in need of immediate attention, but also uncovers sources for novel toxins with potentially useful activities. Pakistan Bungarus sindanus and Naja naja venoms are differentially complex. Naja naja is potently myotoxic. Neither venom is neutralized by Indian antivenom. These results have direct implications for the treatment of envenomed patients in Pakistan. The unusually myotoxic effects of Naja naja demonstrates the value of studying remote populations for biodiscovery. Copyright © 2013 Elsevier B.V. All rights reserved.
Campos, Pollyanna Fernandes; Andrade-Silva, Débora; Zelanis, André; Paes Leme, Adriana Franco; Rocha, Marisa Maria Teixeira; Menezes, Milene Cristina; Serrano, Solange M T; Junqueira-de-Azevedo, Inácio de Loiola Meirelles
Only few studies on snake venoms were dedicated to deeply characterize the toxin secretion of animals from the Colubridae family, despite the fact that they represent the majority of snake diversity. As a consequence, some evolutionary trends observed in venom proteins that underpinned the evolutionary histories of snake toxins were based on data from a minor parcel of the clade. Here, we investigated the proteins of the totally unknown venom from Phalotris mertensi (Dipsadinae subfamily), in order to obtain a detailed profile of its toxins and to appreciate evolutionary tendencies occurring in colubrid venoms. By means of integrated omics and functional approaches, including RNAseq, Sanger sequencing, high-resolution proteomics, recombinant protein production, and enzymatic tests, we verified an active toxic secretion containing up to 21 types of proteins. A high content of Kunitz-type proteins and C-type lectins were observed, although several enzymatic components such as metalloproteinases and an L-amino acid oxidase were also present in the venom. Interestingly, an arguable venom component of other species was demonstrated as a true venom protein and named svLIPA (snake venom acid lipase). This finding indicates the importance of checking the actual protein occurrence across species before rejecting genes suggested to code for toxins, which are relevant for the discussion about the early evolution of reptile venoms. Moreover, trends in the evolution of some toxin classes, such as simplification of metalloproteinases and rearrangements of Kunitz and Wap domains, parallel similar phenomena observed in other venomous snake families and provide a broader picture of toxin evolution. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
G. C. Ferraro
Full Text Available The aim of this study was to evaluate the effect of snake venom derived fibrin glue on the strength oftendon healing in dogs. The deep digital flexor tendon of the 5th digit of 24 thoracic limbs was partially sectioned for adhesive application. On the 7th, 15th, and 30th postoperative day tendons segments were removed for the clinical and biomechanical study. Results indicated that 62.5% of the tendons showed stump retraction and 20.8% moderate to excessive adherence, which affected gliding. The biomechanical evaluation showed that, over time, tendon healing gained progressive resistance for maximum traction and permanent deformations with satisfactory results on the 15th day for rigidity and resilience compared to the other two studied periods. Snake venom derived fibrin glue promotes healing in dog flexor tendon.
Catherine A Vulfius
Full Text Available Phospholipases A2 (PLA2s are enzymes found throughout the animal kingdom. They hydrolyze phospholipids in the sn-2 position producing lysophospholipids and unsaturated fatty acids, agents that can damage membranes. PLA2s from snake venoms have numerous toxic effects, not all of which can be explained by phospholipid hydrolysis, and each enzyme has a specific effect. We have earlier demonstrated the capability of several snake venom PLA2s with different enzymatic, cytotoxic, anticoagulant and antiproliferative properties, to decrease acetylcholine-induced currents in Lymnaea stagnalis neurons, and to compete with α-bungarotoxin for binding to nicotinic acetylcholine receptors (nAChRs and acetylcholine binding protein. Since nAChRs are implicated in postsynaptic and presynaptic activities, in this work we probe those PLA2s known to have strong presynaptic effects, namely β-bungarotoxin from Bungarus multicinctus and crotoxin from Crotalus durissus terrificus. We also wished to explore whether mammalian PLA2s interact with nAChRs, and have examined non-toxic PLA2 from porcine pancreas. It was found that porcine pancreatic PLA2 and presynaptic β-bungarotoxin blocked currents mediated by nAChRs in Lymnaea neurons with IC50s of 2.5 and 4.8 μM, respectively. Crotoxin competed with radioactive α-bungarotoxin for binding to Torpedo and human α7 nAChRs and to the acetylcholine binding protein. Pancreatic PLA2 interacted similarly with these targets; moreover, it inhibited radioactive α-bungarotoxin binding to the water-soluble extracellular domain of human α9 nAChR, and blocked acetylcholine induced currents in human α9α10 nAChRs heterologously expressed in Xenopus oocytes. These and our earlier results show that all snake PLA2s, including presynaptically active crotoxin and β-bungarotoxin, as well as mammalian pancreatic PLA2, interact with nAChRs. The data obtained suggest that this interaction may be a general property of all PLA2s, which
Castro, K L; Duarte, C G; Ramos, H R; Machado de Avila, R A; Schneider, F S; Oliveira, D; Freitas, C F; Kalapothakis, E; Ho, P L; Chávez-Olortegui, C
The main goal of this work was to develop a strategy to identify B-cell epitopes on four different three finger toxins (3FTX) and one phospholipase A2 (PLA2) from Micrurus corallinus snake venom. 3FTx and PLA2 are highly abundant components in Elapidic venoms and are the major responsibles for the toxicity observed in envenomation by coral snakes. Overlapping peptides from the sequence of each toxin were prepared by SPOT method and three different anti-elapidic sera were used to map the epitopes. After immunogenicity analysis of the spot-reactive peptides by EPITOPIA, a computational method, nine sequences from the five toxins were chemically synthesized and antigenically and immunogenically characterized. All the peptides were used together as immunogens in rabbits, delivered with Freund's adjuvant for a first cycle of immunization and Montanide in the second. A good antibody response against individual synthetic peptides and M. corallinus venom was achieved. Anti-peptide IgGs were also cross-reactive against Micrurus frontalis and Micrurus lemniscatus crude venoms. In addition, anti-peptide IgGs inhibits the lethal and phospholipasic activities of M. corallinus crude venom. Our results provide a rational basis to the identification of neutralizing epitopes on coral snake toxins and show that their corresponding synthetic peptides could improve the generation of immuno-therapeutics. The use of synthetic peptide for immunization is a reasonable approach, since it enables poly-specificity, low risk of toxic effects and large scale production. Copyright © 2014 Elsevier Ltd. All rights reserved.
Renjifo, Camila; Smith, Eric N; Hodgson, Wayne C; Renjifo, Juan M; Sanchez, Armando; Acosta, Rodrigo; Maldonado, Jairo H; Riveros, Alain
The venoms of coral snakes (genus Micrurus) are known to induce a broad spectrum of pharmacological activities. While some studies have investigated their potential human effects, little is known about their mechanism of action in terms of the ecological diversity and evolutionary relationships among the group. In the current study we investigated the neuromuscular blockade of the venom of two sister species Micrurus mipartitus and Micrurus dissoleucus, which exhibit divergent ecological characteristics in Colombia, by using the chick biventer cervicis nerve-muscle preparation. We also undertook a phylogenetic analysis of these species and their congeners, in order to provide an evolutionary framework for the American coral snakes. The venom of M. mipartitus caused a concentration-dependant inhibition (3-10 μg/ml) of nerve-mediated twitches and significantly inhibited contractile responses to exogenous ACh (1 mM), but not KCl (40 mM), indicating a postsynaptic mechanism of action. The inhibition of indirect twitches at the lower venom dose (3 μg/ml) showed to be triphasic and the effect was further attenuated when PLA2 was inhibited. M. dissoleucus venom (10-50 μg/ml) failed to produce a complete blockade of nerve-mediated twitches within a 3 h time period and significantly inhibited contractile responses to exogenous ACh (1 mM) and KCl (40 mM), indicating both postsynaptic and myotoxic mechanisms of action. Myotoxic activity was confirmed by morphological studies of the envenomed tissues. Our results demonstrate a hitherto unsuspected diversity of pharmacological actions in closely related species which exhibit divergent ecological characteristics; these results have important implications for both the clinical management of Coral snake envenomings and the design of Micrurus antivenom. Copyright © 2011 Elsevier Ltd. All rights reserved.
... taenicidal, cough remedy, dysentery, cancer, diabetes mellitus, tuberculosis and snake bite remedy. In this report, an attempt has been made to evaluate the bioactive molecules in the plant that are anti-venom agents. Consequently, the stem bark was exhaustively extracted with hexane and subsequently with methanol.
Full Text Available The ethanolic extract from seed kernels of Thai mango (MSKE (Mangifera indica L. cv. ‘Fahlun’ (Anacardiaceae and its major phenolic principle (pentagalloyl glucopyranose exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase A2 (PLA2, hyaluronidase and L-amino acid oxidase (LAAO of Calloselasma rhodostoma (CR and Naja naja kaouthia (NKvenoms by in vitro tests. The anti-hemorrhagic and anti-dermonecrotic activities of MSKE against both venoms were clearly supported by in vivo tests. Molecular docking studies indicated that the phenolic molecules of the MSKE could selectively bind to the active sites or their proximity, or modify conserved residues that are critical for the catalysis of PLA2, and selectively bind to the LAAO binding pocket of both CR and NK venoms and thereby inhibit their enzymatic activities. The results imply a potential use of MSKE against snake venoms.
Full Text Available Agkistrodon halys is one of several dangerous snake species in Iran. Among the most important signs and symptoms in patients envenomated by this snake is disseminated intravascular coagulation. A thrombin-like enzyme, called AH143, was isolated from Agkistrodon halys venom by gel filtration on a Sephadex G-50 column, ion-exchange chromatography on a DEAE-Sepharose and high performance liquid chromatography (HPLC on a C18 column. In the final stage of purification, 0.82 mg of purified enzyme was obtained from 182.5 mg of venom. The purified enzyme showed a single protein band by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE, under reducing conditions, and its molecular mass was found to be about 30 kDa. AH143 revealed clotting activity in human plasma, which was not inhibited by EDTA or heparin. This enzyme still demonstrated coagulation activity when exposed to variations in temperature and pH ranging, respectively, from 30 to 40°C and from 7.0 to 8.0. It also displayed proteolytic activities on synthetic substrate. The purified enzyme did not show any effect on casein. We concluded that the venom of the Iranian snake Agkistrodon halys contains about 0.45% single procoagulant protein which appears to be a thrombin-like enzyme.
Kayena D. Zaqueo
Full Text Available This paper presents a novel serine protease (SP isolated from Bothrops pirajai, a venomous snake found solely in Brazil that belongs to the Viperidae family. The identified SP, named BpirSP-39, was isolated by three chromatographic steps (size exclusion, bioaffinity, and reverse phase chromatographies. The molecular mass of BpirSP-39 was estimated by SDS-PAGE and confirmed by mass spectrometry (39,408.32 Da. The protein was able to form fibrin networks, which was not observed in the presence of serine protease inhibitors, such as phenylmethylsulfonyl fluoride (PMSF. Furthermore, BpirSP-39 presented considerable thermal stability and was apparently able to activate factor XIII of the blood coagulation cascade, unlike most serine proteases. BpirSP-39 was capable of hydrolyzing different chromogenic substrates tested (S-2222, S-2302, and S-2238 while Cu2+ significantly diminished BspirSP-39 activity on the three tested substrates. The enzyme promoted platelet aggregation and also exhibited fibrinogenolytic, fibrinolytic, gelatinolytic, and amidolytic activities. The multiple alignment showed high sequence similarity to other thrombin-like enzymes from snake venoms. These results allow us to conclude that a new SP was isolated from Bothrops pirajai snake venom.
Renu, Kadali; Gopi, Kadiyala; Jayaraman, Gurunathan
The present study reports the formulation of soy protein nanoparticles and its conjugation to antivenom. The conditions for nanoparticle formation were optimised by considering particle size, count rate, stability and zeta potential. The smallest particle size of 70.9 ± 0.9 nm with a zeta potential of -28.0 ± 1.4 mV was obtained at pH 6.2, with NaOH 5.4 % and 28 μg/mg glutaraldehyde. The nanoparticle was conjugated with antisnake venom immunoglobulins (F(ab')2 fragments) using 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide. TEM analysis indicated the increased size of particle to 600 nm after conjugation to antivenom. Further, in vitro studies indicated that conjugated antibodies inhibited the activity of protease, phospholipase and hyaluronidase enzymes of Bungarus caeruleus venom more efficiently than the free antivenom. This is the first report on the use of protein nanoparticles for conjugating snake venom antibodies and their implications for neutralising snake venom enzymes with increased efficiency.
Antúnez, José; Fernández, Julián; Lomonte, Bruno; Angulo, Yamileth; Sanz, Libia; Pérez, Alicia; Calvete, Juan José; Gutiérrez, José María
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 polyspecific (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 highly-effective 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.
Fernández, Julián; Vargas-Vargas, Nancy; Pla, Davinia; Sasa, Mahmood; Rey-Suárez, Paola; Sanz, Libia; Gutiérrez, José María; Calvete, Juan J; Lomonte, Bruno
Protein composition, toxicity, and neutralization of the venoms of Micrurus alleni and Micrurus mosquitensis, two sympatric monadal coral snakes found in humid environments of the Caribbean region of Costa Rica, were studied. Proteomic profiling revealed that these venoms display highly divergent compositions: the former dominated by three-finger toxins (3FTx) and the latter by phospholipases A2 (PLA2). Protein family abundances correlated with enzymatic and toxic characteristics of the venoms. Selective inhibition experiments showed that PLA2s play only a marginal role in the lethal effect of M. alleni venom, but have a major role in M. mosquitensis venom. Proteomic data gathered from other Micrurus species evidenced that the two divergent venom phenotypes are recurrent, and may constitute a general trend across New World elapids. Further, M. mosquitensis, but not M. alleni, venom contains PLA2-like/Kunitz-type inhibitor complex(es) that resemble the ASIC1a/2-activating MitTx heterodimeric toxin isolated from Micrurus tener venom. The evolutionary origin and adaptive relevance of the puzzling phenotypic variability of Micrurus venoms remain to be understood. An antivenom against the PLA2-predominant Micrurus nigrocinctus venom strongly cross-recognized and neutralized M. mosquitensis venom, but only weakly M. alleni venom. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rey-Suárez, Paola; Núñez, Vitelbina; Fernández, Julián; Lomonte, Bruno
In Colombia, nearly 2.8% of the 4200 snakebite accidents recorded annually are inflicted by coral snakes (genus Micrurus). Micrurus dumerilii has a broad distribution in this country, especially in densely populated areas. The proteomic profile of its venom was here studied by a bottom-up approach combining RP-HPLC, SDS-PAGE and MALDI-TOF/TOF. Venom proteins were assigned to eleven families, the most abundant being phospholipases A2 (PLA2; 52.0%) and three-finger toxins (3FTx; 28.1%). This compositional profile shows that M. dumerilii venom belongs to the 'PLA2-rich' phenotype, in the recently proposed dichotomy for Micrurus venoms. Enzymatic and toxic venom activities correlated with protein family abundances. Whole venom induced a conspicuous myotoxic, cytotoxic and anticoagulant effect, and was mildly edematogenic and proteolytic, whereas it lacked hemorrhagic activity. Some 3FTxs and PLA2s reproduced the lethal effect of venom. A coral snake antivenom to Micrurus nigrocinctus demonstrated significant cross-recognition of M. dumerilii venom proteins, and accordingly, ability to neutralize its lethal effect. The combined compositional, functional, and immunological data here reported for M. dumerilii venom may contribute to a better understanding of these envenomings, and support the possible use of anti-M. nigrocinctus coral snake antivenom in their treatment. Coral snakes represent a highly diversified group of elapids in the New World, with nearly 70 species within the genus Micrurus. Owing to their scarce yields, the biochemical composition and toxic activities of coral snake venoms have been less well characterized than those of viperid species. In this work, an integrative view of the venom of M. dumerilii, a medically relevant coral snake from Colombia, was obtained by a combined proteomic, functional, and immunological approach. The venom contains proteins from at least eleven families, with a predominance of phospholipases A2 (PLA2), followed by three
Patiño, Arley Camilo; Pereañez, Jaime Andrés; Gutiérrez, José María; Rucavado, Alexandra
Two clotting serine proteinases, named Cdc SI and Cdc SII, were isolated and characterized for the first time from Colombian Crotalus durissus cumanensis snake venom. The enzymes were purified using two chromatographic steps: molecular exclusion on Sephacryl S-200 and RP-HPLC on C8 Column. The molecular masses of the proteins, determined by MALDI-TOF mass spectrometry, were 28,561.4 and 28,799.2 Da for Cdc SI and Cdc SII, respectively. The aim of the present study was to evaluate enzymatic, coagulant and toxic properties of the two enzymes. The serine proteinases hydrolyzed specific chromogenic substrate (BaPNA) and exhibited a Michaelis-Menten behavior. Cdc SI had V(max) of 0.038 ± 0.003 nmol/min and K(M) of 0.034 ± 0.017 mM, while Cdc SII displayed values of V(max) of 0.267 ± 0.011 nmol/min and K(M) of 0.145 ± 0.023 mM. N-terminal sequences were VIGGDEXNIN and VIGGDICNINEHNFLVALYE for Cdc SI and Cdc SII, respectively. Molecular masses, N-terminal sequences, inhibition assays, and enzymatic profile suggest that Cdc SI and Cdc SII belong to the family of snake venom thrombin-like enzymes. These serine proteinases differed in their clotting activity on human plasma, showing a minimum coagulant dose of 25 μg and 0.571 μg for Cdc SI and Cdc SII, respectively. Enzymes also showed coagulant activity on bovine fibrinogen and degraded chain α of this protein. Toxins lack hemorrhagic and myotoxic activities, but are capable to induce defibrin(ogen)ation, moderate edema, and an increase in vascular permeability. These serine proteinases may contribute indirectly to the local hemorrhage induced by metalloproteinases, by causing blood clotting disturbances, and might also contribute to cardiovascular alterations characteristic of patients envenomed by C. d. cumanensis in Colombia. Copyright © 2012 Elsevier Ltd. All rights reserved.
Dehghani, Rouhullah; Mehrpour, Omid; Shahi, Morteza Panjeh; Jazayeri, Mehrdad; Karrari, Parissa; Keyler, Dan; Zamani, Nasim
Information on the epidemiology of venomous snake species responsible for envenomation to humans in Iran has not been well documented. In the Kashan city, venomous snakebite remains a recurring medical problem. Information providing the correct identification of snake species responsible for envenomation in this geographic region would be useful to regional medical clinics and personnel for the effective and optimal management of the patients. In this cross-sectional study, all patient data was collected from Kashan city and its suburbs. The specific data relating to the taxonomic identification of snakes responsible for envenomation were evaluated. A general approach to the diagnosis and management of patients was also provided. Snakes responsible for bites were transported to a laboratory, where their taxonomic classification was confirmed based on key anatomical features and morphological characteristics. A total of 46 snakes were examined. Of these, 37 (80%) were non-venomous species, and 9 (20%) were identified as venomous. Seven of the nine venomous snake species (78%) were of the family Viperidae, and two specimens (22%) were in the family Colubridae. Specifically, the viperid species were Macrovipera lebetina obtusa, Pseudocerastes persicus, Pseudocerastes fieldi, and Echis carinatus. The two colubrid species were Malpolon monspessulanus insignitus and Psammophis schkari. Five different species of venomous snakes responsible for envenomation in the Kashan city region were confirmed. The viper, P. fieldi, was reported for the first time in the central part of Iran.
Full Text Available Venous ulcers of the lower limbs complicated by infection or chronicity represent a serious public health problem. The elevated number of those afflicted burdens the health services, interferes in quality of life and causes absenteeism. Although there are 2,500 items on the market, ranging from the simplest dressing up to the most complex types of dressing, treatment remains a challenge. Among the substances used, fibrin sealant is the one that promotes diminution of bacterial colonization and of edema, controls hemorrhaging, alters the pain threshold by protecting the nerve endings, hydrates the wound bed and forms granulation tissue that favors healing. Its disadvantages include higher cost and utilization of human fibrinogen that can transmit infectious diseases. The Center for the Study of Venoms and Venomous Animals (CEVAP at São Paulo State University (UNESP developed a new sealant made up of fibrinogen extracted from large animals and from an enzyme obtained from snake venom. The present study, developed in the Health Education Clinic (CEPS of Sacred Heart University (USC aimed to evaluate the effect of the new sealant on the healing process of venous ulcers in 24 adult patients, seven of whom were male and 17 female. Two study groups were formed as follows: Group 1 (G1 - control group of 11 patients treated with essential fatty acid (EFA and Unna's boot, and Group 2 (G2 - 13 patients treated with essential fatty acid (EFA, fibrin sealant and Unna's boot. The follow-up lasted eight weeks and the sealant was applied at only the first and fourth weeks. The results showed that Group 2 presented worse lesion conditions as to healing, but, when comparing the two groups, it was noteworthy that the the sealant was effective in healing venous ulcers. There is evidence that the new sealant is recommended for leg ulcers with the following advantages: ease of application, preparation of the wound bed, diminution of pain and a higher number of
Background Kraits (genus Bungarus) and cobras (genus Naja) are two representative toxic genera of elapids in the old world. Although they are closely related genera and both of their venoms are very toxic, the compositions of their venoms are very different. To unveil their detailed venoms and their evolutionary patterns, we constructed venom gland cDNA libraries and genomic bacterial artificial chromosome (BAC) libraries for Bungarus multicinctus and Naja atra, respectively. We sequenced about 1500 cDNA clones for each of the venom cDNA libraries and screened BAC libraries of the two snakes by blot analysis using four kinds of toxin probes; i.e., three-finger toxin (3FTx), phospholipase A2 (PLA2), kunitz-type protease inhibitor (Kunitz), and natriuretic peptide (NP). Results In total, 1092 valid expressed sequences tags (ESTs) for B. multicinctus and 1166 ESTs for N. atra were generated. About 70% of these ESTs can be annotated as snake toxin transcripts. 3FTx (64.5%) and β bungarotoxin (25.1%) comprise the main toxin classes in B. multicinctus, while 3FTx (95.8%) is the dominant toxin in N. atra. We also observed several less abundant venom families in B. multicinctus and N. atra, such as PLA2, C-type lectins, and Kunitz. Peculiarly a cluster of NP precursors with tandem NPs was detected in B. multicinctus. A total of 71 positive toxin BAC clones in B. multicinctus and N. atra were identified using four kinds of toxin probes (3FTx, PLA2, Kunitz, and NP), among which 39 3FTx-postive BACs were sequenced to reveal gene structures of 3FTx toxin genes. Conclusions Based on the toxin ESTs and 3FTx gene sequences, the major components of B. multicinctus venom transcriptome are neurotoxins, including long chain alpha neurotoxins (α-ntx) and the recently originated β bungarotoxin, whereas the N. atra venom transcriptome mainly contains 3FTxs with cytotoxicity and neurotoxicity (short chain α-ntx). The data also revealed that tandem duplications contributed the most to
Francischetti, Ivo M. B.; My-Pham, Van; Harrison, Jim; Garfield, Mark K.; Ribeiro, José M. C.
The venom gland of the snake Bitis gabonica (Gaboon viper) was used for the first time to construct a unidirectional cDNA phage library followed by high-throughput sequencing and bioinformatic analysis. Hundreds of cDNAs were obtained and clustered into contigs. We found mostly novel full-length cDNA coding for metalloproteases (P-II and P-III classes), Lys49-phospholipase A2, serine proteases with essential mutations in the active site, Kunitz protease inhibitors, several C-type lectins, bradykinin-potentiating peptide, vascular endothelial growth factor, nucleotidases and nucleases, nerve growth factor, and L-amino acid oxidases. Two new members of the recently described short coding region family of disintegrin, displaying RGD and MLD motifs are reported. In addition, we have identified for the first time a cytokine-like molecule and a multi-Kunitz protease inhibitor in snake venoms. The CLUSTAL alignment and the unrooted cladograms for selected families of B. gabonica venom proteins are also presented. A significant number of sequences were devoid of database matches, suggesting that their biologic function remains to be identified. This paper also reports the N-terminus of the 15 most abundant venom proteins and the sequences matching their corresponding transcripts. The electronic version of this manuscript, available on request, contains spreadsheets with hyperlinks to FASTA-formatted files for each contig and the best match to the GenBank and Conserved Domain Databases, in addition to CLUSTAL alignments of each contig. We have thus generated a comprehensive catalog of the B. gabonica venom gland, containing for each secreted protein: i) the predicted molecular weight, ii) the predicted isoelectric point, iii) the accession number, and iv) the putative function. The role of these molecules is discussed in the context of the envenomation caused by the Gaboon viper. PMID:15276202
Ana María Henao Duque
Full Text Available Red-tail coral snake (Micrurus mipartitus is a long and thin bicolor coral snake widely distributed in Colombia and is the coral that causes the majority of accidents in the Andean region, so it is important to keep this species in captivity for anti-venom production and research. However, maintaining this species in captivity is very difficult because it refuses to feed, in addition to the high mortality rate due to maladaptation syndrome. In this study a force feeding diet, diverse substrates for maintenance and a milking technique were evaluated. Additionally, individual variability of the venom was determined by High Performance Liquid Chromatography (HPLC, Sodium Dodecyl Sulfate- Polyacrylamide Gel Electrophoresis (SDS-PAGE and Coagulant, Anticoagulant and Hemolytic activities. The results of this study demonstrate that it was possible to increase the survival rate of this species in captivity and to determine some of the important factors in the maintenance. As to the individual variability of the venom, we found differences in number and intensity of peaks recovered by chromatography and also displayed variations in some of its biological activities.
Abdelkafi-Koubaa, Zaineb; Jebali, Jed; Othman, Houcemeddine; Morjen, Maram; Aissa, Imen; Zouari-Kesentini, Raoudha; Bazaa, Amine; Ellefi, Amen Allah; Majdoub, Hafedh; Srairi-Abid, Najet; Gargouri, Youssef; El Ayeb, Mohamed; Marrakchi, Naziha
A new L-amino acid oxidase (LAAO) from Cerastes cerastes snake venom, named CC-LAAO, was purified to homogeneity using a combination of size-exclusion, ion-exchange and affinity chromatography. CC-LAAO is a homodimeric glycosylated flavoprotein with a molecular mass around 58 kDa under reducing conditions and about 115 kDa in its native form when analyzed by SDS-PAGE and gel filtration chromatography, respectively. This enzyme displayed a Michaelis-Menten behavior with an optimal pH at 7.8. However, unlike known SV-LAAOs which display their maximum activity at 37 °C, CC-LAAO has an optimal temperature at 50 °C. Kinetic studies showed that the enzyme displayed high specificity towards hydrophobic L-amino acids. The best substrates were L-Phe, L-Met and L-Leu. CC-LAAO activity was inhibited by the substrate analog N-acetyl tryptophan. The N-terminal amino acid sequence of this protein was determined by automated Edman degradation. The CC-LAAO cDNA was cloned from the venom gland total RNA preparation. The cDNA sequence contained an open-reading frame (ORF) of 1551-bp, which encoded a protein of 516 amino acids comprising a signal peptide of 18 amino acids and 498-residues mature protein. CC-LAAO sequence and its tertiary model shared high similarity with other snake venom LAAOs. Copyright © 2014 Elsevier Ltd. All rights reserved.
Full Text Available Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science and articles of peer-reviewed journals. Results: Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5’nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.
Pochanugool, C; Wildde, H; Bhanganada, K; Chanhome, L; Cox, M J; Chaiyabutr, N; Sitprija, V
We reviewed a total of 2,525 snakebite patients in Bangkok. Of these, 1,415 were bitten by venomous snakes, 91 by neurotoxic snakes of genus Naja or Bungarus and 1,324 by snakes of family Viperidae or Crotalidae. Seventy-one percent of bites were on the lower extremity. There were two fatal cobra bites; both patients were dead on arrival at the hospital. Bites from vipers caused morbidity but no deaths. Species-specific antivenins are effective in reversing respiratory failure from cobra bites and coagulopathies from bites by Viperidae and Crotalidae snakes. However, early respiratory and wound care will save lives even in the absence of specific cobra and krait antivenin. Care of a snakebite victim should consist of immobilization and bandaging of the bitten limb with elastic bandages during transport to the hospital, early surgical debridement of necrotic tissue, appropriate infusion of antivenin, aggressive respiratory support, management of shock and infection, and peritoneal dialysis or hemodialysis. Incision of bite wounds, suctioning, application of ice, and tourniquets are of no proven value and may be dangerous. All snakebite victims in southeast Asia should survive if they receive early competent care.
Full Text Available In Mexico, medicinal plants are widely used. The use of Randia aculeata by healers against snakebites has never been scientifically tested in relation to possible effects on blood parameters and muscle tissue damage. Interviews were carried out in Jamapa, Veracuz, Mexico, with local residents to collect information about the traditional use of Randia aculeata. In this locality, seven pieces of fruit from the plant are mixed in a liter of alcohol, and then administered orally against snakebites. By using histological techniques and a murine model, we explored its cytoprotective properties against the effects of Crotalus simus and Bothrops asper venoms. Possible protections provided by the plant against tissue damage to skeletal and cardiac muscles and against the typical loss of red blood cells were analyzed. Randia aculeata caused an increase in microhematocrit and total hemoglobin, parameters that are often decremented in association with the loss of red blood cells, which is a characteristic effect of animal venom. Randia aculeata was also shown to protect against the lowering of platelet levels caused by Bothrops asper venom. Finally, Randia aculeata produced a partial inhibition of necrosis following administration of snake venom in skeletal and myocardial muscles. The present results provide solid evidence for the traditional use of Randia aculeata against snakebites, as demonstrated by protection against muscular tissue damage and the diminution of red blood cells.
Full Text Available A new PLA2 (Bp-13 was purified from Bothrops pauloensis snake venom after a single chromatographic step of RP-HPLC on μ-Bondapak C-18. Amino acid analysis showed a high content of hydrophobic and basic amino acids and 14 half-cysteine residues. The N-terminal sequence showed a high degree of homology with basic Asp49 PLA2 myotoxins from other Bothrops venoms. Bp-13 showed allosteric enzymatic behavior and maximal activity at pH 8.1, 36°–45°C. Full Bp-13 PLA2 activity required Ca2+; its PLA2 activity was inhibited by Mg2+, Mn2+, Sr2+, and Cd2+ in the presence and absence of 1 mM Ca2+. In the mouse phrenic nerve-diaphragm (PND preparation, the time for 50% paralysis was concentration-dependent (P0.05. The main effect of this new Asp49 PLA2 of Bothrops pauloensis venom is on muscle fiber sarcolemma, with avian preparation being less responsive than rodent preparation. The study enhances biochemical and pharmacological characterization of B. pauloensis venom.
Paixão-Cavalcante, Danielle; Kuniyoshi, Alexandre K.; Portaro, Fernanda C. V.; da Silva, Wilmar Dias; Tambourgi, Denise V.
Background An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms. Methodology/Principal Findings The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1–7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested. Conclusion These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms. PMID:25643358
Full Text Available An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms.The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1-7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested.These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms.
Full Text Available A myotoxin from the venom of the snake Bothrops brazili has been purified by ion-exchange chromatography on CM-Sephadex C-50 with 0,05 M ammonium acetate buffer pH 7. The homogeneity was evaluated by PAGE with and without SDS, immunodiffusion and immunoelectrophoresis. The myotoxin is a basic protein with 15,6% of Lys+Arg; it is not a glicoprotein, has not enzymatic activity, and corresponds to 25% of the whole venom protein. The molecular weight of the myotoxin was determined by PAGE-SDS and gel filtration chromatography. The myotoxin has 30 KDa of molecular weight and two polypeptide chains of 15 KDa each. Myotoxin produces a severe necrosis on the gastrocnemius muscle of white mice. The myotoxin does not have hemolytic nor anticoagulant activity. However, produces edema with a DEM of 32,6 mg of protein.
Barbizan, Roberta; Castro, Mateus V; Rodrigues, Antônio C; Barraviera, Benedito; Ferreira, Rui S; Oliveira, Alexandre L R
Ventral root avulsion is an experimental model of proximal axonal injury at the central/peripheral nervous system interface that results in paralysis and poor clinical outcome after restorative surgery. Root reimplantation may decrease neuronal degeneration in such cases. We describe the use of a snake venom-derived fibrin sealant during surgical reconnection of avulsed roots at the spinal cord surface. The present work investigates the effects of this fibrin sealant on functional recovery, neuronal survival, synaptic plasticity, and glial reaction in the spinal motoneuron microenvironment after ventral root reimplantation. Female Lewis rats (7 weeks old) were subjected to VRA and root replantation. The animals were divided into two groups: 1) avulsion only and 2) replanted roots with fibrin sealant derived from snake venom. Post-surgical motor performance was evaluated using the CatWalk system twice a week for 12 weeks. The rats were sacrificed 12 weeks after surgery, and their lumbar intumescences were processed for motoneuron counting and immunohistochemistry (GFAP, Iba-1 and synaptophysin antisera). Array based qRT-PCR was used to evaluate gene regulation of several neurotrophic factors and receptors as well as inflammatory related molecules. The results indicated that the root reimplantation with fibrin sealant enhanced motor recovery, preserved the synaptic covering of the motoneurons and improved neuronal survival. The replanted group did not show significant changes in microglial response compared to VRA-only. However, the astroglial reaction was significantly reduced in this group. In conclusion, the present data suggest that the repair of avulsed roots with snake venom fibrin glue at the exact point of detachment results in neuroprotection and preservation of the synaptic network at the microenvironment of the lesioned motoneurons. Also such procedure reduced the astroglial reaction and increased mRNA levels to neurotrophins and anti
Full Text Available BACKGROUND: Ventral root avulsion is an experimental model of proximal axonal injury at the central/peripheral nervous system interface that results in paralysis and poor clinical outcome after restorative surgery. Root reimplantation may decrease neuronal degeneration in such cases. We describe the use of a snake venom-derived fibrin sealant during surgical reconnection of avulsed roots at the spinal cord surface. The present work investigates the effects of this fibrin sealant on functional recovery, neuronal survival, synaptic plasticity, and glial reaction in the spinal motoneuron microenvironment after ventral root reimplantation. METHODOLOGY/PRINCIPAL FINDINGS: Female Lewis rats (7 weeks old were subjected to VRA and root replantation. The animals were divided into two groups: 1 avulsion only and 2 replanted roots with fibrin sealant derived from snake venom. Post-surgical motor performance was evaluated using the CatWalk system twice a week for 12 weeks. The rats were sacrificed 12 weeks after surgery, and their lumbar intumescences were processed for motoneuron counting and immunohistochemistry (GFAP, Iba-1 and synaptophysin antisera. Array based qRT-PCR was used to evaluate gene regulation of several neurotrophic factors and receptors as well as inflammatory related molecules. The results indicated that the root reimplantation with fibrin sealant enhanced motor recovery, preserved the synaptic covering of the motoneurons and improved neuronal survival. The replanted group did not show significant changes in microglial response compared to VRA-only. However, the astroglial reaction was significantly reduced in this group. CONCLUSIONS/SIGNIFICANCE: In conclusion, the present data suggest that the repair of avulsed roots with snake venom fibrin glue at the exact point of detachment results in neuroprotection and preservation of the synaptic network at the microenvironment of the lesioned motoneurons. Also such procedure reduced the
Ticli, Fábio K; Hage, Lorane I S; Cambraia, Rafael S; Pereira, Paulo S; Magro, Angelo J; Fontes, Marcos R M; Stábeli, Rodrigo G; Giglio, José R; França, Suzelei C; Soares, Andreimar M; Sampaio, Suely V
Many plants are used in traditional medicine as active agents against various effects induced by snakebite. The methanolic extract from Cordia verbenacea (Cv) significantly inhibited paw edema induced by Bothrops jararacussu snake venom and by its main basic phospholipase A2 homologs, namely bothropstoxins I and II (BthTXs). The active component was isolated by chromatography on Sephadex LH-20 and by RP-HPLC on a C18 column and identified as rosmarinic acid (Cv-RA). Rosmarinic acid is an ester of caffeic acid and 3,4-dihydroxyphenyllactic acid [2-O-cafeoil-3-(3,4-di-hydroxy-phenyl)-R-lactic acid]. This is the first report of RA in the species C. verbenacea ('baleeira', 'whaler') and of its anti-inflammatory and antimyotoxic properties against snake venoms and isolated toxins. RA inhibited the edema and myotoxic activity induced by the basic PLA2s BthTX-I and BthTX-II. It was, however, less efficient to inhibit the PLA2 activity of BthTX-II and, still less, the PLA2 and edema-inducing activities of the acidic isoform BthA-I-PLA2 from the same venom, showing therefore a higher inhibitory activity upon basic PLA2s. RA also inhibited most of the myotoxic and partially the edema-inducing effects of both basic PLA2s, thus reinforcing the idea of dissociation between the catalytic and pharmacological domains. The pure compound potentiated the ability of the commercial equine polyvalent antivenom in neutralizing lethal and myotoxic effects of the crude venom and of isolated PLA2s in experimental models. CD data presented here suggest that, after binding, no significant conformation changes occur either in the Cv-RA or in the target PLA2. A possible model for the interaction of rosmarinic acid with Lys49-PLA2 BthTX-I is proposed.
Rey-Suárez, Paola; Núñez, Vitelbina; Saldarriaga-Córdoba, Mónica; Lomonte, Bruno
Snake venom phospholipases A 2 (PLA 2 ) share high sequence identities and a conserved structural scaffold, but show important functional differences. Only a few PLA 2 s have been purified and characterized from coral snake (Micrurus spp.) venoms, and their role in envenomation remains largely unknown. In this report, we describe the isolation, sequencing and partial functional characterization of two Micrurus PLA 2 s: MmipPLA 2 from Micrurus mipartitus and MdumPLA 2 from Micrurus dumerilii, two species of clinical importance in Colombia. MmipPLA 2 consisted of 119 amino acid residues with a predicted pI of 8.4, whereas MdumPLA 2 consisted of 117 residues with a pI of 5.6. Both PLA 2 s showed the conserved 'group I' cysteine pattern and were enzymatically active, although MdumPLA 2 had higher activity. The two enzymes differed notably in their toxicity, with MmipPLA 2 being highly lethal to mice and mildly myotoxic, whereas MdumPLA 2 was not lethal (up to 3 μg/g body weight) but strongly myotoxic. MdumPLA 2 displayed higher anticoagulant activity than MmipPLA 2 in vitro and caused more sustained edema in the mouse footpad assay. Neither of these enzymes was cytolytic to cultured skeletal muscle C2C12 myotubes. Based on their structural differences, the two enzymes were placed in separate lineages in a partial phylogeny of Micrurus venom PLA 2 s and this classification agreed with their divergent biological activities. Overall, these findings highlight the structural and functional diversity of Micrurus venom PLA 2 s. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.
Pałgan, K; Kuźmiński, A; Janik, A; Gotz-Żbikowska, M; Bartuzi, Z
Vipera berus bites lead to a variety of clinical manifestations. Local swelling, coagulopathy, nephrotoxicity, cardiac effects and myotoxicity are known to be associated with envenoming by a viper bite...
Abdelkafi-Koubaa, Zaineb; Jebali, Jed; Othman, Houcemeddine; Morjen, Maram; Aissa, Imen; Zouari-Kesentini, Raoudha; Bazaa, Amine; Ellefi, Amen Allah; Majdoub, Hafedh; Srairi-Abid, Najet; Gargouri, Youssef; El Ayeb, Mohamed; Marrakchi, Naziha
International audience; A new l-amino acid oxidase (LAAO) from Cerastes cerastes snake venom, named CC-LAAO, was purified to homogeneity using a combination of size-exclusion, ion-exchange and affinity chromatography. CC-LAAO is a homodimeric glycosylated flavoprotein with a molecular mass around 58 kDa under reducing conditions and about 115 kDa in its native form when analyzed by SDS-PAGE and gel filtration chromatography, respectively. This enzyme displayed a Michaelis-Menten behavior with...
Rokyta, Darin R; Wray, Kenneth P; Margres, Mark J
Snake venoms generally show sequence and quantitative variation within and between species, but some rattlesnakes have undergone exceptionally rapid, dramatic shifts in the composition, lethality, and pharmacological effects of their venoms. Such shifts have occurred within species, most notably in Mojave (Crotalus scutulatus), South American (C. durissus), and timber (C. horridus) rattlesnakes, resulting in some populations with extremely potent, neurotoxic venoms without the hemorrhagic effects typical of rattlesnake bites. To better understand the evolutionary changes that resulted in the potent venom of a population of C. horridus from northern Florida, we sequenced the venom-gland transcriptome of an animal from this population for comparison with the previously described transcriptome of the eastern diamondback rattlesnake (C. adamanteus), a congener with a more typical rattlesnake venom. Relative to the toxin transcription of C. adamanteus, which consisted primarily of snake-venom metalloproteinases, C-type lectins, snake-venom serine proteinases, and myotoxin-A, the toxin transcription of C. horridus was far simpler in composition and consisted almost entirely of snake-venom serine proteinases, phospholipases A2, and bradykinin-potentiating and C-type natriuretic peptides. Crotalus horridus lacked significant expression of the hemorrhagic snake-venom metalloproteinases and C-type lectins. Evolution of shared toxin families involved differential expansion and loss of toxin clades within each species and pronounced differences in the highly expressed toxin paralogs. Toxin genes showed significantly higher rates of nonsynonymous substitution than nontoxin genes. The expression patterns of nontoxin genes were conserved between species, despite the vast differences in toxin expression. Our results represent the first complete, sequence-based comparison between the venoms of closely related snake species and reveal in unprecedented detail the rapid evolution of
Hatakeyama, Daniela M; de Morais-Zani, Karen; Serino-Silva, Caroline; Grego, Kathleen F; Sant'Anna, Savio S; Fernandes, Wilson; Aniz, Patrícia A E A; Torquato, Ricardo J S; Tanaka, Aparecida S; Sanz, Libia; Calvete, Juan J; Tanaka-Azevedo, Anita M
The number of snakes donated to the Brazilian Instituto Butantan has been decreasing in the past 10 years. This circumstance motivated us to compare the properties of five venom pools of Bothrops jararaca snake stored for up to 54 years. Results showed differences among venom pools regarding enzymatic and other biological activities, such as caseinolytic, phospholipase A2, hemorrhagic and coagulant activities, as well as antigenicity. Protein content, reverse-phase chromatographic profile, and immunorecognition by commercial Bothrops antivenom were comparable for all venom pools, although lethality of the most recent preparations was higher. Since the lowest functional activities did not always correspond to older venoms, differences among venom pools used for antivenom production during the period 1963-2008 may correlate with the different proportions of venoms from different localities used in their generation, rather than to long-term storage. We conclude that B. jararaca venoms properly stored for long periods of time retain their structural and pharmacological activities, thus representing useful materials for scientific research and antivenom production. Copyright © 2017 Elsevier Ltd. All rights reserved.
Van Cao, Nguyen; Thien Tao, Nguyen; Moore, Amelia; Montoya, Alfred; Redsted Rasmussen, Arne; Broad, Kenneth; Voris, Harold K; Takacs, Zoltan
Conservation of sea snakes is virtually nonexistent in Asia, and its role in human-snake interactions in terms of catch, trade, and snakebites as an occupational hazard is mostly unexplored. We collected data on sea snake landings from the Gulf of Thailand, a hotspot for sea snake harvest by squid fishers operating out of the ports of Song Doc and Khanh Hoi, Ca Mau Province, Vietnam. The data were collected during documentation of the steps of the trading process and through interviewers with participants in the trade. Squid vessels return to ports once per lunar synodic cycle and fishers sell snakes to merchants who sort, package, and ship the snakes to various destinations in Vietnam and China for human consumption and as a source of traditional remedies. Annually, 82 t, roughly equal to 225,500 individuals, of live sea snakes are brought to ports. To our knowledge, this rate of harvest constitutes one of the largest venomous snake and marine reptile harvest activities in the world today. Lapemis curtus and Hydrophis cyanocinctus constituted about 85% of the snake biomass, and Acalyptophis peronii, Aipysurus eydouxii, Hydrophis atriceps, H. belcheri, H. lamberti, and H. ornatus made up the remainder. Our results establish a quantitative baseline for characteristics of catch, trade, and uses of sea snakes. Other key observations include the timing of the trade to the lunar cycle, a decline of sea snakes harvested over the study period (approximately 30% decline in mass over 4 years), and the treatment of sea snake bites with rhinoceros horn. Emerging markets in Southeast Asia drive the harvest of venomous sea snakes in the Gulf of Thailand and sea snake bites present a potentially lethal occupational hazard. We call for implementation of monitoring programs to further address the conservation implications of this large-scale marine reptile exploitation. © 2014 Society for Conservation Biology.
Full Text Available BACKGROUND: Snake Venom Metalloproteinases (SVMPs are amongst the key enzymes that contribute to the high toxicity of snake venom. We have recently shown that snake venoms from the Bothrops genus activate the Complement system (C by promoting direct cleavage of C-components and generating anaphylatoxins, thereby contributing to the pathology and spread of the venom. The aim of the present study was to isolate and characterize the C-activating protease from Bothrops pirajai venom. RESULTS: Using two gel-filtration chromatography steps, a metalloproteinase of 23 kDa that activates Complement was isolated from Bothrops pirajai venom. The mass spectrometric identification of this protein, named here as C-SVMP, revealed peptides that matched sequences from the P-I class of SVMPs. C-SVMP activated the alternative, classical and lectin C-pathways by cleaving the α-chain of C3, C4 and C5, thereby generating anaphylatoxins C3a, C4a and C5a. In vivo, C-SVMP induced consumption of murine complement components, most likely by activation of the pathways and/or by direct cleavage of C3, leading to a reduction of serum lytic activity. CONCLUSION: We show here that a P-I metalloproteinase from Bothrops pirajai snake venom activated the Complement system by direct cleavage of the central C-components, i.e., C3, C4 and C5, thereby generating biologically active fragments, such as anaphylatoxins, and by cleaving the C1-Inhibitor, which may affect Complement activation control. These results suggest that direct complement activation by SVMPs may play a role in the progression of symptoms that follow envenomation.
... to a more positive activity, like dancing to music, coloring, or playing a game. Discipline usually is not necessary, since most kids don't realize biting hurts. If you've tried the steps above and ...
Hayes, William K; Mackessy, Stephen P
Recent reports in the lay press have suggested that bites by rattlesnakes in the last several years have been more severe than those in the past. The explanation, often citing physicians, is that rattlesnakes are evolving more toxic venom, perhaps in response to anthropogenic causes. We suggest that other explanations are more parsimonious, including factors dependent on the snake and factors associated with the bite victim's response to envenomation. Although bites could become more severe from an increased proportion of bites from larger or more provoked snakes (ie, more venom injected), the venom itself evolves much too slowly to explain the severe symptoms occasionally seen. Increased snakebite severity could also result from a number of demographic changes in the victim profile, including age and body size, behavior toward the snake (provocation), anatomical site of bite, clothing, and general health including asthma prevalence and sensitivity to foreign antigens. Clinical management of bites also changes perpetually, rendering comparisons of snakebite severity over time tenuous. Clearly, careful study taking into consideration many factors will be essential to document temporal changes in snakebite severity or venom toxicity. Presently, no published evidence for these changes exists. The sensationalistic coverage of these atypical bites and accompanying speculation is highly misleading and can produce many detrimental results, such as inappropriate fear of the outdoors and snakes, and distraction from proven snakebite management needs, including a consistent supply of antivenom, adequate health care, and training. We urge healthcare providers to avoid propagating misinformation about snakes and snakebites. Copyright (c) 2010 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Olamendi-Portugal, Timoteo; Batista, Cesar V F; Restano-Cassulini, Rita; Pando, Victoria; Villa-Hernandez, Oscar; Zavaleta-Martínez-Vargas, Alfonso; Salas-Arruz, Maria C; Rodríguez de la Vega, Ricardo C; Becerril, Baltazar; Possani, Lourival D
The protein composition of the soluble venom from the South American fish-eating coral snake Micrurus surinamensis surinamensis, here abbreviated M. surinamensis, was separated by RP-HPLC and 2-DE, and their components were analyzed by automatic Edman degradation, MALDI-TOF and ESI-MS/MS. Approximately 100 different molecules were identified. Sixty-two components possess molecular masses between 6 and 8 kDa, are basically charged molecules, among which are cytotoxins and neurotoxins lethal to fish (Brachidanios rerio). Six new toxins (abbreviated Ms1-Ms5 and Ms11) were fully sequenced. Amino acid sequences similar to the enzymes phospholipase A2 and amino acid oxidase were identified. Over 20 additional peptides were identified by sequencing minor components of the HPLC separation and from 2-DE gels. A functional assessment of the physiological activity of the six toxins was also performed by patch clamp using muscular nicotinic acetylcholine receptor assays. Variable degrees of blockade were observed, most of them reversible. The structural and functional data obtained were used for phylogenetic analysis, providing information on some evolutionary aspects of the venom components of this snake. This contribution increases by a factor of two the total number of alpha-neurotoxins sequenced from the Micrurus genus in currently available literature.
Ploug, M; Ellis, V
-anchored membrane proteins. Recent evidence has highlighted similarities between the individual domains of uPAR and the large family of secreted, single domain snake venom alpha-neurotoxins, suggesting that uPAR may adopt the same gross folding pattern as these structurally well characterized proteins. Structural...
Carlos Hubinger Tokarnia
ível pela determinação precisa do quadro clínico-patológico. Com base nos dados disponíveis e em nossa experiência, somos da opinião que os acidentes ofídicos fatais em bovinos são bem menos freqüentes do que se acredita, isto é, sua importância vem sendo bastante superestimada.A review of the literature shows that opinions on the importance of snake bites as cause of cattle death in Brazil are divergent among veterinarians; some think they are of no importance or of only minor significance, others are of the opinion that snake bites are frequent. However, the literature only reports two confirmed fatal cases by Bothrops and none by Crotalus in cattle in the country. A questionnaire which was submitted for appraisal to veterinary pathologists and clinicians in various States of Brazil, revealed only suspected cases of fatal accidents by snakes in cattle. During our field and laboratory diagnostic work we never made a diagnosis of a snake bite accident. Many "diagnoses" have apparently been made at a distance from where the animals died, without clinical and post-mortem examination, nor histological studies. By this way, the great majority of cases seems to be only supposition. In Brazil there are only few snakes of the genus Bothrops theoretically able to produce sufficient amounts of venom to kill an adult bovine. Nevertheless, in experiments, only Bothrops alternatus was able to cause the death of just one out of three bovines bitten, and this animal only weighed 279 kg. Snakes of the genus Crotalus can produce sufficient amounts of venom to kill an adult bovine; however it is known, that snakes of the genus Crotalus as well as of Bothrops generally inoculate only a part of their venom. These considerations indicate that the deaths suspected to have been caused by snake bites in cattle in Brazil have to be studied more thoroughly. A diagnosis can only be confirmed by establishing the precise clinical and pathological picture. Our current opinion is that fatal
Background Snake venom metalloproteinases (SVMPs) are widely distributed in snake venoms and are versatile toxins, targeting many important elements involved in hemostasis, such as basement membrane proteins, clotting proteins, platelets, endothelial and inflammatory cells. The functional diversity of SVMPs is in part due to the structural organization of different combinations of catalytic, disintegrin, disintegrin-like and cysteine-rich domains, which categorizes SVMPs in 3 classes of precursor molecules (PI, PII and PIII) further divided in 11 subclasses, 6 of them belonging to PII group. This heterogeneity is currently correlated to genetic accelerated evolution and post-translational modifications. Results Thirty-one SVMP cDNAs were full length cloned from a single specimen of Bothrops neuwiedi snake, sequenced and grouped in eleven distinct sequences and further analyzed by cladistic analysis. Class P-I and class P-III sequences presented the expected tree topology for fibrinolytic and hemorrhagic SVMPs, respectively. In opposition, three distinct segregations were observed for class P-II sequences. P-IIb showed the typical segregation of class P-II SVMPs. However, P-IIa grouped with class P-I cDNAs presenting a 100% identity in the 365 bp at their 5' ends, suggesting post-transcription events for interclass recombination. In addition, catalytic domain of P-IIx sequences segregated with non-hemorrhagic class P-III SVMPs while their disintegrin domain grouped with other class P-II disintegrin domains suggesting independent evolution of catalytic and disintegrin domains. Complementary regions within cDNA sequences were noted and may participate in recombination either at DNA or RNA levels. Proteins predicted by these cDNAs show the main features of the correspondent classes of SVMP, but P-IIb and P-IIx included two additional cysteines cysteines at the C-termini of the disintegrin domains in positions not yet described. Conclusions In B. neuwiedi venom gland
Bénard-Valle, Melisa; Carbajal-Saucedo, Alejandro; de Roodt, Adolfo; López-Vera, Estuardo; Alagón, Alejandro
The objective of this study was to identify the venom components that could play a relevant role during envenomation caused by the coral snake Micrurus tener, through its biochemical characterization as well as the analysis of its effects on a murine model. Furthermore, it aimed to evaluate crude venom, in addition to its components, for possible specificity of action on a natural prey model (Conopsis lineata). The toxicity of the crude venom (delivered subcutaneously) showed a significant difference between the Median Lethal Dose (LD₅₀) in mice (4.4 μg/g) and in Conopsis lineata (12.1 μg/g) that was not observed when comparing the Median Paralyzing Dose (PD₅₀) values (mice = 4.7 μg/g; snakes = 4.1 μg/g). These results are evidence that the choice of study model strongly influences the apparent effects of crude venom. Moreover, based on the observed physical signs in the animal models, it was concluded that the most important physical effect caused by the venom is flaccid paralysis, which facilitates capture and subduing of prey regardless of whether it is alive; death is a logical consequence of the lack of oxygenation. Venom fractionation using a C18 reverse phase column yielded 35 fractions from which 16.6% caused paralysis and/or death to both animal models, 21.9% caused paralysis and/or death only to C. lineata and 1.6% were murine specific. Surprisingly, the diversity of snake-specific fractions did not reflect a difference between the PD₅₀s of the crude venom in mice and snakes, making it impossible to assume some type of specificity for either of the study models. Finally, the great diversity and abundance of fractions with no observable effect in snakes or mice (42.7%) suggested that the observed lethal fractions are not the only relevant toxic fractions within the venom and emphasized the possible relevance of interaction between components to generate the syndrome caused by the venom as a whole. Copyright © 2013 Elsevier Ltd. All rights
Vieira, Lara F; Magro, Angelo J; Fernandes, Carlos A H; de Souza, Bibiana M; Cavalcante, Walter L G; Palma, Mário S; Rosa, José C; Fuly, André L; Fontes, Marcos R M; Gallacci, Márcia; Butzke, Diana S; Calderon, Leonardo A; Stábeli, Rodrigo G; Giglio, José R; Soares, Andreimar M
Crotoxin is a neurotoxin from Crotalus durissus terrificus venom that shows immunomodulatory, anti-inflammatory, antimicrobial, antitumor and analgesic activities. Structurally, this toxin is a heterodimeric complex composed by a toxic basic PLA2 (Crotoxin B or CB) non-covalently linked to an atoxic non-enzymatic and acidic component (Crotapotin, Crotoxin A or CA). Several CA and CB isoforms have been isolated and characterized, showing that the crotoxin venom fraction is, in fact, a mixture of different molecules derived from the combination of distinct subunit isoforms. Intercro (IC) is a protein from the same snake venom which presents high similarity in primary structure to CB, indicating that it could be an another isoform of this toxin. In this work, we compare IC to the crotoxin complex (CA/CB) and/or CB in order to understand its functional aspects. The experiments with IC revealed that it is a new toxin with different biological activities from CB, keeping its catalytic activity but presenting low myotoxicity and absence of neurotoxic activity. The results also indicated that IC is structurally similar to CB isoforms, but probably it is not able to form a neurotoxic active complex with crotoxin A as observed for CB. Moreover, structural and phylogenetic data suggest that IC is a new toxin with possible toxic effects not related to the typical CB neurotoxin. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Abba, Yusuf; Ilyasu, Yusuf Maina; Noordin, Mustapha Mohamed
Captivity of non-venomous snakes such as python and boa are common in zoos, aquariums and as pets in households. Poor captivity conditions expose these reptiles to numerous pathogens which may result in disease conditions. The purpose of this study was to investigate the common bacteria isolated from necropsied captive snakes in Malaysia over a five year period. A total of 27 snake carcasses presented for necropsy at the Universiti Putra Malaysia (UPM) were used in this survey. Samples were aseptically obtained at necropsy from different organs/tissues (lung, liver, heart, kindey, oesophagus, lymph node, stomach, spinal cord, spleen, intestine) and cultured onto 5% blood and McConkey agar, respectively. Gram staining, morphological evaluation and biochemical test such as oxidase, catalase and coagulase were used to tentatively identify the presumptive bacterial isolates. Pythons had the highest number of cases (81.3%) followed by anaconda (14.8%) and boa (3.7%). Mixed infection accounted for 81.5% in all snakes and was highest in pythons (63%). However, single infection was only observed in pythons (18.5%). A total of 82.7%, 95.4% and 100% of the bacterial isolates from python, anaconda and boa, respectively were gram negative. Aeromonas spp was the most frequently isolated bacteria in pythons and anaconda with incidences of 25 (18%) and 8 (36.6%) with no difference (p > 0.05) in incidence, respectively, while Salmonella spp was the most frequently isolated in boa and significantly higher (p snakes have public health importance and have been incriminated in human infections worldwide. Copyright © 2017 Elsevier Ltd. All rights reserved.
Félix-Silva, Juliana; Souza, Thiago; Menezes, Yamara A. S.; Cabral, Bárbara; Câmara, Rafael B. G.; Silva-Junior, Arnóbio A.; Rocha, Hugo A. O.; Rebecchi, Ivanise M. M.; Zucolotto, Silvana M.; Fernandes-Pedrosa, Matheus F.
Snakebites are a serious public health problem due their high morbi-mortality. The main available specific treatment is the antivenom serum therapy, which has some disadvantages, such as poor neutralization of local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies is relevant. Therefore, the aim of this study was to evaluate the antiophidic properties of Jatropha gossypiifolia, a medicinal plant used in folk medicine to treat snakebites. The aqueous leaf extract of the plant was prepared by decoction and phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins. The extract was able to inhibit enzymatic and biologic activities induced by Bothrops jararaca snake venom in vitro and in vivo. The blood incoagulability was efficiently inhibited by the extract by oral route. The hemorrhagic and edematogenic local effects were also inhibited, the former by up to 56% and the latter by 100%, in animals treated with extract by oral and intraperitoneal routes, respectively. The inhibition of myotoxic action of B. jararaca reached almost 100%. According to enzymatic tests performed, it is possible to suggest that the antiophidic activity may be due an inhibitory action upon snake venom metalloproteinases (SVMPs) and/or serine proteinases (SVSPs), including fibrinogenolytic enzymes, clotting factors activators and thrombin like enzymes (SVTLEs), as well upon catalytically inactive phospholipases A2 (Lys49 PLA2). Anti-inflammatory activity, at least partially, could also be related to the inhibition of local effects. Additionally, protein precipitating and antioxidant activities may also be important features contributing to the activity presented. In conclusion, the results demonstrate the potential antiophidic activity of J. gossypiifolia extract, including its significant action upon local effects, suggesting that
Lomonte, Bruno; Sasa, Mahmood; Rey-Suárez, Paola; Bryan, Wendy; Gutiérrez, José María
Micrurus clarki is an uncommon coral snake distributed from the Southeastern Pacific of Costa Rica to Western Colombia, for which no information on its venom could be found in the literature. Using a 'venomics' approach, proteins of at least nine families were identified, with a moderate predominance of three-finger toxins (3FTx; 48.2%) over phospholipase A₂ (PLA₂; 36.5%). Comparison of this venom profile with those of other Micrurus species suggests that it may represent a more balanced, 'intermediate' type within the dichotomy between 3FTx- and PLA₂-predominant venoms. M. clarki venom was strongly cross-recognized and, accordingly, efficiently neutralized by an equine therapeutic antivenom against M. nigrocinctus, revealing their high antigenic similarity. Lethal activity for mice could be reproduced by a PLA₂ venom fraction, but, unexpectedly, not by fractions corresponding to 3FTxs. The most abundant venom component, hereby named clarkitoxin-I, was identified as a short-chain (type I) 3FTx, devoid of lethal effect in mice, whose target remains to be defined. Its amino acid sequence of 66 residues shows high similarity with predicted sequences of venom gland transcripts described for M. fulvius, M. browni, and M. diastema.
Full Text Available Animal venoms represent a valuable source of bioactive peptides that can be derived into useful pharmacological tools, or even innovative drugs. In this way, the venom of Dendroaspis angusticeps (DA, the Eastern Green Mamba, has been intensively studied during recent years. It mainly contains hundreds of large toxins from 6 to 9 kDa, each displaying several disulfide bridges. These toxins are the main target of venom-based studies due to their valuable activities obtained by selectively targeting membrane receptors, such as ion channels or G-protein coupled receptors. This study aims to demonstrate that the knowledge of venom composition is still limited and that animal venoms contain unexpected diversity and surprises. A previous study has shown that Dendroaspis angusticeps venom contains not only a cocktail of classical toxins, but also small glycosylated peptides. Following this work, a deep exploration of DA glycopeptidome by a dual nano liquid chromatography coupled to electrospray ionization mass spectrometry (nanoLC-ESI-MS and Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS analyses was initiated. This study reveals unsuspected structural diversity of compounds such as 221 glycopeptides, displaying different glycan structures. Sequence alignments underline structural similarities with natriuretic peptides already characterized in Elapidae venoms. Finally, the presence of an S-cysteinylation and hydroxylation of proline on four glycopeptides, never described to date in snake venoms, is also revealed by proteomics and affined by nuclear magnetic resonance (NMR experiments.
Cañas, Carlos A.; Castro-Herrera, Fernando; Castaño-Valencia, Santiago
Abstract Background Although the red-tailed coral snake (Micrurus mipartitus) is widely distributed in Colombia and its venom is highly neurotoxic and life threatening, envenomation by this species is rare. Therefore, this report may shed some light on the clinical presentation of M. mipartitus bites. Case presentations Herein, we describe two cases of patients bitten by red-tailed coral snakes, illustrating the clinical presentation of the victims, the outcomes and treatment provided. C...
Sousa, Leijiane F; Portes-Junior, José A; Nicolau, Carolina A; Bernardoni, Juliana L; Nishiyama-Jr, Milton Y; Amazonas, Diana R; Freitas-de-Sousa, Luciana A; Mourão, Rosa Hv; Chalkidis, Hipócrates M; Valente, Richard H; Moura-da-Silva, Ana M
neutralized by Bothrops antivenom. Thus, using a functional proteomic approach, we highlighted intraspecific differences in B. atrox venom that could impact both in the ecology of snakes but also in the treatment of snake bite patients in the region. Copyright © 2017 Elsevier B.V. All rights reserved.
A survey on some biochemical and pharmacological activities of venom from two Colombian colubrid snakes, Erythrolamprus bizona (Double-banded coral snake mimic) and Pseudoboa neuwiedii (Neuwied's false boa).
Torres-Bonilla, Kristian A; Floriano, Rafael S; Schezaro-Ramos, Raphael; Rodrigues-Simioni, Léa; da Cruz-Höfling, Maria Alice
Colombian colubrid snake venoms have been poorly studied. They represent a great resource of biological, ecological, toxinological and pharmacological research. We assessed some enzymatic properties and neuromuscular effects of Erythrolamprus bizona and Pseudoboa neuwiedii venoms from Colombia. Proteolytic, amidolytic and phospholipase A 2 (PLA 2 ) activities were analyzed using colorimetric assays and the neuromuscular activity was analyzed in chick biventer cervicis (BC) preparations. The venom of both species showed very low PLA 2 and amidolytic activities; however, both exhibited high proteolytic activity, which in E. bizona venom surpassed that of P. neuwiedii venom. E. bizona and P. neuwiedii venoms provoked partial neuromuscular blockade, which was more prominent in P. neuwiedii venom. E. bizona venom (30 μg/ml) induced a significant potentiation of the contracture response to exogenous ACh (110 μM), which was not accompanied by twitch height alteration, whereas the highest venom concentration (100 μg/ml) inhibited contracture responses to both ACh and KCl (40 mM). In contrast, P. neuwiedii venom (30 and 100 μg/ml) caused significant reduction in the contracture responses to exogenous ACh and KCl. The morphological analyses showed high myotoxic effects in the muscle fibers of BC incubated with either venoms; however, they are more prominent in the P. neuwiedii venom. Our results suggest that the myotoxicity of the venom of the two Colombian species can be ascribed to their high proteolytic activity. An interesting data was the potentiation of the ACh-induced contracture, but not the twitch height, caused by E. bizona venom, at a concentration that is harmless to muscle fibers integrity. This phenomenon remains to be further elucidated, and suggest that a possible involvement of post-synaptic receptors cannot be discarded. This work is a contribution to expand the knowledge on colubrid venoms; it allows envisaging that the two venoms offer
Daryl C. Yang
Full Text Available Millions of years of evolution have fine-tuned the ability of venom peptides to rapidly incapacitate both prey and potential predators. Toxicofera reptiles are characterized by serous-secreting mandibular or maxillary glands with heightened levels of protein expression. These glands are the core anatomical components of the toxicoferan venom system, which exists in myriad points along an evolutionary continuum. Neofunctionalisation of toxins is facilitated by positive selection at functional hotspots on the ancestral protein and venom proteins have undergone dynamic diversification in helodermatid and varanid lizards as well as advanced snakes. A spectacular point on the venom system continuum is the long-glanded blue coral snake (Calliophis bivirgatus, a specialist feeder that preys on fast moving, venomous snakes which have both a high likelihood of prey escape but also represent significant danger to the predator itself. The maxillary venom glands of C. bivirgatus extend one quarter of the snake’s body length and nestle within the rib cavity. Despite the snake’s notoriety its venom has remained largely unstudied. Here we show that the venom uniquely produces spastic paralysis, in contrast to the flaccid paralysis typically produced by neurotoxic snake venoms. The toxin responsible, which we have called calliotoxin (δ-elapitoxin-Cb1a, is a three-finger toxin (3FTx. Calliotoxin shifts the voltage-dependence of NaV1.4 activation to more hyperpolarised potentials, inhibits inactivation, and produces large ramp currents, consistent with its profound effects on contractile force in an isolated skeletal muscle preparation. Voltage-gated sodium channels (NaV are a particularly attractive pharmacological target as they are involved in almost all physiological processes including action potential generation and conduction. Accordingly, venom peptides that interfere with NaV function provide a key defensive and predatory advantage to a range of
Yang, Daryl C.; Deuis, Jennifer R.; Dashevsky, Daniel; Dobson, James; Jackson, Timothy N. W.; Brust, Andreas; Xie, Bing; Koludarov, Ivan; Debono, Jordan; Hendrikx, Iwan; Hodgson, Wayne C.; Josh, Peter; Nouwens, Amanda; Baillie, Gregory J.; Bruxner, Timothy J. C.; Alewood, Paul F.; Lim, Kelvin Kok Peng; Frank, Nathaniel; Vetter, Irina; Fry, Bryan G.
Millions of years of evolution have fine-tuned the ability of venom peptides to rapidly incapacitate both prey and potential predators. Toxicofera reptiles are characterized by serous-secreting mandibular or maxillary glands with heightened levels of protein expression. These glands are the core anatomical components of the toxicoferan venom system, which exists in myriad points along an evolutionary continuum. Neofunctionalisation of toxins is facilitated by positive selection at functional hotspots on the ancestral protein and venom proteins have undergone dynamic diversification in helodermatid and varanid lizards as well as advanced snakes. A spectacular point on the venom system continuum is the long-glanded blue coral snake (Calliophis bivirgatus), a specialist feeder that preys on fast moving, venomous snakes which have both a high likelihood of prey escape but also represent significant danger to the predator itself. The maxillary venom glands of C. bivirgatus extend one quarter of the snake’s body length and nestle within the rib cavity. Despite the snake’s notoriety its venom has remained largely unstudied. Here we show that the venom uniquely produces spastic paralysis, in contrast to the flaccid paralysis typically produced by neurotoxic snake venoms. The toxin responsible, which we have called calliotoxin (δ-elapitoxin-Cb1a), is a three-finger toxin (3FTx). Calliotoxin shifts the voltage-dependence of NaV1.4 activation to more hyperpolarised potentials, inhibits inactivation, and produces large ramp currents, consistent with its profound effects on contractile force in an isolated skeletal muscle preparation. Voltage-gated sodium channels (NaV) are a particularly attractive pharmacological target as they are involved in almost all physiological processes including action potential generation and conduction. Accordingly, venom peptides that interfere with NaV function provide a key defensive and predatory advantage to a range of invertebrate
Eric A Gehrie
Full Text Available The venom of Loxosceles reclusa (Brown Recluse spider can cause a severe, life-threatening hemolysis in humans for which no therapy is currently available in the USA beyond supportive measures. Because this hemolysis is uncommon, relatively little is known about its clinical manifestation, diagnosis, or management. Here, we aimed to clarify the clinical details of envenomation, to determine the efficacy of the complement inhibitor eculizumab to prevent the hemolysis in vitro, and to investigate markers of exposure to Brown Recluse venom.We performed a 10-year chart review of cases of Brown Recluse spider bite-mediated hemolysis at our institution. We also designed an in vitro assay to test the efficacy of eculizumab to inhibit hemolysis of venom exposed red blood cells. Finally, we compared levels of CD55, CD59 and glycophorin A on venom exposed versus venom-naïve cells.Most victims of severe Brown Recluse spider mediated hemolysis at our institution are children and follow an unpredictable clinical course. Brown Recluse spider bite mediated hemolysis is reduced by 79.2% (SD=18.8% by eculizumab in vitro. Erythrocyte glycophorin A, but not CD55 or CD59, is reduced after red blood cells are incubated with venom in vitro.Taken together, our laboratory data and clinical observations indicate that L. reclusa venom exposure results in non-specific antibody and complement fixation on red blood cells, resulting in complement mediated hemolysis that is curtailed by the complement inhibitor eculizumab in vitro. Glycophorin A measurement by flow cytometry may help to identify victims of L. reclusa envenomation.
Gehrie, Eric A; Nian, Hui; Young, Pampee P
The venom of Loxosceles reclusa (Brown Recluse spider) can cause a severe, life-threatening hemolysis in humans for which no therapy is currently available in the USA beyond supportive measures. Because this hemolysis is uncommon, relatively little is known about its clinical manifestation, diagnosis, or management. Here, we aimed to clarify the clinical details of envenomation, to determine the efficacy of the complement inhibitor eculizumab to prevent the hemolysis in vitro, and to investigate markers of exposure to Brown Recluse venom. We performed a 10-year chart review of cases of Brown Recluse spider bite-mediated hemolysis at our institution. We also designed an in vitro assay to test the efficacy of eculizumab to inhibit hemolysis of venom exposed red blood cells. Finally, we compared levels of CD55, CD59 and glycophorin A on venom exposed versus venom-naïve cells. Most victims of severe Brown Recluse spider mediated hemolysis at our institution are children and follow an unpredictable clinical course. Brown Recluse spider bite mediated hemolysis is reduced by 79.2% (SD=18.8%) by eculizumab in vitro. Erythrocyte glycophorin A, but not CD55 or CD59, is reduced after red blood cells are incubated with venom in vitro. Taken together, our laboratory data and clinical observations indicate that L. reclusa venom exposure results in non-specific antibody and complement fixation on red blood cells, resulting in complement mediated hemolysis that is curtailed by the complement inhibitor eculizumab in vitro. Glycophorin A measurement by flow cytometry may help to identify victims of L. reclusa envenomation.
Camila M Adade
Full Text Available The neglected human diseases caused by trypanosomatids are currently treated with toxic therapy with limited efficacy. In search for novel anti-trypanosomatid agents, we showed previously that the Crotalus viridis viridis (Cvv snake venom was active against infective forms of Trypanosoma cruzi. Here, we describe the purification of crovirin, a cysteine-rich secretory protein (CRISP from Cvv venom with promising activity against trypanosomes and Leishmania.Crude venom extract was loaded onto a reverse phase analytical (C8 column using a high performance liquid chromatographer. A linear gradient of water/acetonitrile with 0.1% trifluoroacetic acid was used. The peak containing the isolated protein (confirmed by SDS-PAGE and mass spectrometry was collected and its protein content was measured. T. cruzi trypomastigotes and amastigotes, L. amazonensis promastigotes and amastigotes and T. brucei rhodesiense procyclic and bloodstream trypomastigotes were challenged with crovirin, whose toxicity was tested against LLC-MK2 cells, peritoneal macrophages and isolated murine extensor digitorum longus muscle. We purified a single protein from Cvv venom corresponding, according to Nano-LC MS/MS sequencing, to a CRISP of 24,893.64 Da, henceforth referred to as crovirin. Human infective trypanosomatid forms, including intracellular amastigotes, were sensitive to crovirin, with low IC50 or LD50 values (1.10-2.38 µg/ml. A considerably higher concentration (20 µg/ml of crovirin was required to elicit only limited toxicity on mammalian cells.This is the first report of CRISP anti-protozoal activity, and suggests that other members of this family might have potential as drugs or drug leads for the development of novel agents against trypanosomatid-borne neglected diseases.
Adade, Camila M; Carvalho, Ana Lúcia O; Tomaz, Marcelo A; Costa, Tatiana F R; Godinho, Joseane L; Melo, Paulo A; Lima, Ana Paula C A; Rodrigues, Juliany C F; Zingali, Russolina B; Souto-Padrón, Thaïs
The neglected human diseases caused by trypanosomatids are currently treated with toxic therapy with limited efficacy. In search for novel anti-trypanosomatid agents, we showed previously that the Crotalus viridis viridis (Cvv) snake venom was active against infective forms of Trypanosoma cruzi. Here, we describe the purification of crovirin, a cysteine-rich secretory protein (CRISP) from Cvv venom with promising activity against trypanosomes and Leishmania. Crude venom extract was loaded onto a reverse phase analytical (C8) column using a high performance liquid chromatographer. A linear gradient of water/acetonitrile with 0.1% trifluoroacetic acid was used. The peak containing the isolated protein (confirmed by SDS-PAGE and mass spectrometry) was collected and its protein content was measured. T. cruzi trypomastigotes and amastigotes, L. amazonensis promastigotes and amastigotes and T. brucei rhodesiense procyclic and bloodstream trypomastigotes were challenged with crovirin, whose toxicity was tested against LLC-MK2 cells, peritoneal macrophages and isolated murine extensor digitorum longus muscle. We purified a single protein from Cvv venom corresponding, according to Nano-LC MS/MS sequencing, to a CRISP of 24,893.64 Da, henceforth referred to as crovirin. Human infective trypanosomatid forms, including intracellular amastigotes, were sensitive to crovirin, with low IC50 or LD50 values (1.10-2.38 µg/ml). A considerably higher concentration (20 µg/ml) of crovirin was required to elicit only limited toxicity on mammalian cells. This is the first report of CRISP anti-protozoal activity, and suggests that other members of this family might have potential as drugs or drug leads for the development of novel agents against trypanosomatid-borne neglected diseases.
Full Text Available Coral snakes (Micrurus spp. are the main representatives of the Elapidae in South America. However, bites by these snakes are uncommon. We retrospectively reviewed the data from 11 individuals bitten by coral snakes over a 20-year period; four were confirmed (snake brought for identification and seven were highly suspected (neuromuscular manifestations cases of elapid envenoming. The cases were classified as dry-bite (n = 1, caused by M. lemniscatus; did not receive antivenom, mild (n = 2, local manifestations with no acute myasthenic syndrome; M. frontalis and Micrurus spp., moderate (n = 5, mild myasthenia or severe (n = 3, important myasthenia; one of them caused by M. frontalis. The main clinical features upon admission were paresthesia (local, n = 9; generalized, n = 2, local pain (n = 8, palpebral ptosis (n = 8, weakness (n = 4 and inability to stand up (n = 3. No patient developed respiratory failure. Antivenom was used in ten cases, with mild early reactions occurring in three. An anticholinesterase drug was administered in the three severe cases, with a good response in two. No deaths were observed. Despite the high toxicity of coral snake venoms, the prognosis following envenoming is good. In serious bites by M. frontalis or M. lemniscatus, the venom of which acts postsynaptically, anticholinesterases may be useful as an ancillary measure if antivenom is unavailable, if there is a delay in obtaining a sufficient amount, or in those patients given the highest recommended doses of antivenom without improvement of the paralysis or with delayed recovery.As serpentes corais (Micrurus spp. são as principais representantes dos elapídeos na América do Sul. Todavia, acidentes com essas serpentes são raros. Foram revisados retrospectivamente os prontuários de 11 pacientes mordidos por corais num período de 20 anos. Destes 11 casos, quatro foram casos confirmados por identificação da serpente e sete como casos altamente suspeitos de
Thaisa Francielle Souza Domingos
Full Text Available The ability of crude extracts of the brown seaweed Spatoglossum schröederi to counteract some of the biological activities of Lachesis muta snake venom was evaluated. In vitro assays showed that only the extract of S. schröederi prepared in ethyl acetate was able to inhibit the clotting of fibrinogen induced by L. muta venom. On the other hand, all extracts were able to inhibit partially the hemolysis caused by venom and those prepared in dichloromethane or ethyl acetate fully neutralized the proteolysis and hemorrhage produced by the venom. Moreover, the dichloromethane or ethyl acetate extracts inhibited the hemolysis induced by an isolated phospholipase A2 from L. muta venom, called LM-PLA2-I. In contrast, the hexane extract failed to protect mice from hemorrhage or to inhibit proteolysis and clotting. These results show that the polarity of the solvent used to prepare the extracts of S. schröederi algae influenced the potency of the inhibitory effect of the biological activities induced by L. muta venom. Thus, the seaweed S. schröederi may be a promising source of natural inhibitors of the enzymes involved in biological activities of L. muta venom.
Full Text Available Micrurus clarki is an uncommon coral snake distributed from the Southeastern Pacific of Costa Rica to Western Colombia, for which no information on its venom could be found in the literature. Using a ‘venomics’ approach, proteins of at least nine families were identified, with a moderate predominance of three-finger toxins (3FTx; 48.2% over phospholipase A2 (PLA2; 36.5%. Comparison of this venom profile with those of other Micrurus species suggests that it may represent a more balanced, ‘intermediate’ type within the dichotomy between 3FTx- and PLA2-predominant venoms. M. clarki venom was strongly cross-recognized and, accordingly, efficiently neutralized by an equine therapeutic antivenom against M. nigrocinctus, revealing their high antigenic similarity. Lethal activity for mice could be reproduced by a PLA2 venom fraction, but, unexpectedly, not by fractions corresponding to 3FTxs. The most abundant venom component, hereby named clarkitoxin-I, was identified as a short-chain (type I 3FTx, devoid of lethal effect in mice, whose target remains to be defined. Its amino acid sequence of 66 residues shows high similarity with predicted sequences of venom gland transcripts described for M. fulvius, M. browni, and M. diastema.
Full Text Available The authors studied the bacterial contamination of rattlesnake venom isolated from snakes in captivity and wild snakes caught recently. The captive snakes showed a relatively high incidence of bacterial contamination of their venom.
Full Text Available Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2 activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2 inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite.
Silva, Luciana Miato Gonçalves; Silva, Camila Aparecida Alves da; Silva, Aline da; Vieira, Rodolfo Paula; Mesquita-Ferrari, Raquel Agnelli; Cogo, José Carlos; Zamuner, Stella Regina
.... Several studies have shown the effectiveness of low level laser (LLL) therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown...
phospholipids preradiolabeled by feeding the cells 1.4C-fatty acids overnight. To develop potential prophylactic and therapeutic agents, pharmacological studies...PLAz neurotoxins. Experimental Methods: Materials. Vencm from 1 nAjA atra, CTX from Naja n9ja kaouthia venom (Lots 125F-4007), bee venom PLAz ( Apis ... mellifera ), melittin, B-bungarotoxin, Tris base, Hepes (4-(2-hydroxyethyl)-l-piperazineethanesulfonic acid), Mes (4- morpholineethanesulfonic acid), bovine
Pimolpan Pithayanukul; Jiraporn Leanpolchareanchai; Patchreenart Saparpakorn
Snakebite envenomations cause severe local tissue necrosis and the venom metalloproteinases are thought to be the key toxins involved. In this study, the ethanolic extract from seed kernels of Thai mango (Mangifera indica L. cv. ‘Fahlun’) (Anacardiaceae) and its major phenolic principle (pentagalloylglucopyranose) exhibited potent and dose−dependent inhibitory effects on the caseinolytic and fibrinogenolytic activities of Malayan pit viper and Thai cobra venoms in in vitro tests. molecular do...
Sousa Marcelo V
Full Text Available Abstract Background Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Previous studies have demonstrated that the biological and pharmacological activities of B. atrox venom alter with the age of the animal. Here, we present a comparative proteome analysis of B. atrox venom collected from specimens of three different stages of maturation: juveniles, sub-adults and adults. Results Optimized conditions for two-dimensional gel electrophoresis (2-DE of pooled venom samples were achieved using immobilized pH gradient (IPG gels of non-linear 3–10 pH range during the isoelectric focusing step and 10–20% gradient polyacrylamide gels in the second dimension. Software-assisted analysis of the 2-DE gels images demonstrated differences in the number and intensity of spots in juvenile, sub-adult and adult venoms. Although peptide mass fingerprinting (PMF failed to identify even a minor fraction of spots, it allowed us to group spots that displayed similar peptide maps. The spots were subjected to a combination of tandem mass spectrometry and Mascot and MS BLAST database searches that identified several classes of proteins, including metalloproteinases, serine proteinases, lectins, phospholipases A2, L-amino oxidases, nerve growth factors, vascular endothelial growth factors and cysteine-rich secretory proteins. Conclusion The analysis of B. atrox samples from specimens of different ages by 2-DE and mass spectrometry suggested that venom proteome alters upon ontogenetic development. We identified stage specific and differentially expressed polypeptides that may be responsible for the activities of the venom in each developmental stage. The results provide insight into the molecular basis of the relation between symptomatology of snakebite accidents in humans and the venom composition. Our findings underscore the importance of the use of venoms from individual specimen at various stages of maturation for
Paniagua, D; Jiménez, L; Romero, C; Vergara, I; Calderón, A; Benard, M; Bernas, M J; Rilo, H; de Roodt, A; D' Suze, G; Witte, M H; Boyer, L; Alagón, A
The contribution of the lymphatic system to the absorption and systemic bioavailability of Micrurus fulvius venom after subcutaneous (SC) administration was assessed using a central lymph-cannulated sheep model. Micrurus fulvius venom was administered either by intravenous bolus (IV) or subcutaneous injection (SC) in 12 sheep with and without thoracic duct cannulation and drainage. Venom concentration in serum and lymph was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) in samples collected over a 6-hour period and in tissues harvested at the end of the experiment. Pharmacokinetic parameters were determined by a non-compartmental analysis. In the lymphatic cannulated group, over the 6 hours after the venom was administered, 69% of administered dose was accounted for in blood (45%) and lymph (25%). Negligible levels of venom were detected in organs and urine implying that the steady state observed after SC administration is maintained by a slow absorption process. Comparison of kinetics of the thoracic duct cannulated and non-cannulated groups showed that lymphatic absorption contributed in an important way to maintenance of this steady state. These results show that the limiting process in the pharmacokinetics of Micrurus fulvius venom following SC administration is absorption, and that the lymphatic system plays a key role in this process.
Bustillo, Soledad; García-Denegri, María Emilia; Gay, Carolina; Van de Velde, Andrea C; Acosta, Ofelia; Angulo, Yamileth; Lomonte, Bruno; Gutiérrez, José María; Leiva, Laura
Microvessel disruption leading to hemorrhage stands among the most dangerous consequences of envenomings by snakes of the family Viperidae. A PIII metalloproteinase (SVMP), balteragin, purified from the venom of the snake Bothrops alternatus, displays a potent hemorrhagic effect, and a moderate myotoxicity in vivo. Previous studies described the ability of this SVMP to induce the detachment of C2C12 myoblasts in culture, without causing cytolysis. Surprisingly, a purified acidic phospholipase A2 (PLA2) from the same venom was found to increase this detaching activity of the SVMP on myoblasts. Since endothelial cells are a natural target of SVMPs in vivo, the possibility that this synergistic effect is also observed on this cell type was explored in the present work. In addition, a first approach of the mechanism of action of this effect was studied. Results clearly confirm that the acidic PLA2, despite lacking toxicity towards endothelial cells, significantly enhances the detaching effect of the SVMP even at a concentration as low as 1 μg/mL. Inhibition of enzymatic activity of the PLA2 by chemical modification with p-bromophenacyl bromide did not affect the synergistic activity, suggesting that this effect is not dependent on phospholipase enzymatic activity and may instead be the consequence of an interaction of the PLA2 with endothelial cell plasma membrane. To our knowledge, this is the first report of a synergistic action of a non toxic PLA2 in enhancing the detachment of endothelial cells induced by a metalloproteinase. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Lubich, Carol; Krenzelok, Edward P
Emergency departments throughout the USA may have some familiarity with the management of envenomation from indigenous snake species such as Crotalinae (rattlesnakes) and Micrurus (coral snakes). However, venomous species may include exotic reptiles whose bites pose substantial treatment challenges due to both a lack of experience and the difficulty in obtaining antivenoms. Two pet cobra envenomation incidents illustrate the challenges that face emergency departments, especially in urban settings, that are confronted with these exposures. It is important for emergency departments to be aware of the large underground presence of exotic venomous reptile pets and to utilise the expertise of regional poison centres that will also assist in the procurement of exotic antivenoms.
Nature Naturally, 1983
Designed for students in grades 4-6, the teaching unit presents illustrations and facts about snakes. Topics include common snakes found in the United States, how snakes eat, how snakes shed their skin, poisonous snakes, the Eastern Indigo snake, and the anatomy of a snake. A student page includes a crossword puzzle and surprising snake facts. A…
Casais-E-Silva, Luciana L; Teixeira, Catarina F P; Lebrun, Ivo; Lomonte, Bruno; Alape-Girón, Alberto; Gutiérrez, José María
The venom of Micrurus lemniscatus, a coral snake of wide geographical distribution in South America, was fractionated by reverse-phase HPLC and the fractions screened for phospholipase A2 (PLA2) activity. The major component of the venom, a PLA2, here referred to as 'Lemnitoxin', was isolated and characterized biochemically and toxicologically. It induces myotoxicity upon intramuscular or intravenous injection into mice. The amino acid residues Arg15, Ala100, Asn108, and a hydrophobic residue at position 109, which are characteristic of myotoxic class I phospholipases A2, are present in Lemnitoxin. This PLA2 is antigenically related to M. nigrocinctus nigroxin, Notechis scutatus notexin, Pseudechis australis mulgotoxin, and Pseudonaja textilis textilotoxin, as demonstrated with monoclonal and polyclonal antibodies. Lemnitoxin is highly selective in its targeting of cells, being cytotoxic for differentiated myotubes in vitro and muscle fibers in vivo, but not for undifferentiated myoblasts or endothelial cells. Lemnitoxin is not lethal after intravenous injection at doses up to 2μg/g in mice, evidencing its lack of significant neurotoxicity. Lemnitoxin displays anticoagulant effect on human plasma and proinflammatory activity also, as it induces paw edema and mast cell degranulation. Thus, the results of this work demonstrate that Lemnitoxin is a potent myotoxic and proinflammatory class I PLA2. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Julve Parreño, Jose Manuel; Huet, Estefanía; Fernández-Del-Carmen, Asun; Segura, Alvaro; Venturi, Micol; Gandía, Antoni; Pan, Wei-Song; Albaladejo, Irene; Forment, Javier; Pla, Davinia; Wigdorovitz, Andrés; Calvete, Juan J; Gutiérrez, Carlos; Gutiérrez, José María; Granell, Antonio; Orzáez, Diego
Antivenoms developed from the plasma of hyperimmunized animals are the only effective treatment available against snakebite envenomation but shortage of supply contributes to the high morbidity and mortality toll of this tropical disease. We describe a synthetic biology approach to affordable and cost-effective antivenom production based on plant-made recombinant polyclonal antibodies (termed pluribodies). The strategy takes advantage of virus superinfection exclusion to induce the formation of somatic expression mosaics in agroinfiltrated plants, which enables the expression of complex antibody repertoires in a highly reproducible manner. Pluribodies developed using toxin-binding genetic information captured from peripheral blood lymphocytes of hyperimmunized camels recapitulated the overall binding activity of the immune response. Furthermore, an improved plant-made antivenom (plantivenom) was formulated using an in vitro selected pluribody against Bothrops asper snake venom toxins and has been shown to neutralize a wide range of toxin activities and provide protection against lethal venom doses in mice. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Full Text Available Several colubrid snakes produce venomous oral secretions. In this work, the venom collected from Venezuelan opisthoglyphous (rear-fanged Philodryas olfersii snake was studied. Different proteins were present in its venom and they were characterized by 20% SDS-PAGE protein electrophoresis. The secretion exhibited proteolytic (gelatinase activity, which was partially purified on a chromatography ionic exchange mono Q2 column. Additionally, the haemorrhagic activity of Philodryas olfersii venom on chicken embryos, mouse skin and peritoneum was demonstrated. Neurotoxic symptoms were demonstrated in mice inoculated with Philodryas olfersii venom. In conclusion, Philodryas olfersii venom showed proteolytic, haemorrhagic, and neurotoxic activities, thus increasing the interest in the high toxic action of Philodryas venom.Várias serpentes da família Colubridae produzem secreções orais venenosas. Neste trabalho, foi estudado o veneno coletado da presa posterior da serpente opistóglifa venezuelana Philodryas olfersii. Deferentes proteínas estavam presentes no veneno, sendo caracterizadas pela eletroforese de proteínas (SDS-PAGE a 20%. A secreção mostrou atividade proteolítica (gelatinase a qual foi parcialmente purificada em uma coluna de intercâmbio iônico (mono Q2. Adicionalmente, a atividade hemorrágica do veneno de Philodryas olfersii foi demonstrada em embriões de galinha, pele e peritônio de rato. Os sintomas neurológicos foram demonstrados em camundongos inoculados com veneno de Philodryas olfersii. Em conclusão, o veneno da Philodryas olfersii mostrou atividade proteolítica, hemorrágica, e neurotóxica, assim aumentando o interesse na elevada ação tóxica do veneno da Philodryas olfersii.
Full Text Available We tested the capacity of leaf (Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, and Satureja viminea and root (Uncaria tomentosa extracts to inhibit edema induced by Bothrops asper snake venom. Edema-forming activity was studied plethysmographically in the rat hind paw model. Groups of rats were injected intraperitoneally with various doses of each extract and, one hour later, venom was injected subcutaneously in the right hind paw. Edema was assessed at various time intervals. The edematogenic activity was inhibited in those animals that received an injection U. tomentosa, C. nutans or L. speciosa extract. The extract of U. baccifera showed a slight inhibition of the venom effect. Extract from S. viminea and, to a lesser extent that of U. leptuphylla, induced a pro-inflammatory effect, increasing the edema at doses of 250 mg/kg at one and two hours. Rev. Biol. Trop. 54(2: 245-252. Epub 2006 Jun 01.Se investigó la capacidad de los extractos de las hojas de Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, Satureja viminea y de la raíz de Uncaria tomentosa para inhibir el edema inducido por el veneno de Bothrops asper por métodos pletismométricos. Los grupos de ratas fueron inyectados intraperitonealmente con varias dosis de cada extracto y una hora mas tarde se inyectó veneno por vía subcutánea en la pata trasera derecha de la rata. Se evaluó el edema en distintos intervalos de tiempo. Los resultados muestran que la actividad edematogénica fue inhibida en los animales que recibieron los extractos de raíz de U. tomentosa, hojas de C. nutans y L. speciosa. Los extractos de hojas de U. baccifera mostraron leve inhibición del efecto del veneno. El extracto de hojas de S. viminea y en menor grado el de U. leptuphylla indujeron un efecto pro inflamatorio.
Méndez, Ileana; Gutiérrez, José María; Angulo, Yamileth; Calvete, Juan J; Lomonte, Bruno
Venoms of several Naja species found in Sub-Saharan Africa, and commonly known as "spitting cobras", induce a predominantly cytotoxic pattern of envenomings that may evolve into tissue necrosis and gangrene. Cytotoxic components of their venoms have been identified as members of the three-finger toxin and phospholipase A(2) protein families. In this study, an in vitro assay using the myogenic cell line C2C12, was utilized to compare the cytolytic activities of venoms from five species of spitting cobras: Naja nigricollis, Naja katiensis, Naja pallida, Naja nubiae, and Naja mossambica. These venoms were strongly cytotoxic, causing a 50% effect at ~1.5 μg/well (15 μg/ml), except for N. katiensis venom, which required nearly twice this amount. Using the cell-based assay, the ability of an equine polyspecific antivenom (EchiTab-Plus-ICP) to neutralize cytotoxicity was assessed. The antivenom completely inhibited the cytotoxic activity of all five venoms, although high antivenom/venom ratios were needed. Neutralization curves displayed the following decreasing order of efficiency: N. nubiae > N. pallida > N. mossambica > N. nigricollis > N. katiensis. Results indicate that neutralizing antibodies toward toxins responsible for this particular effect are present in the antivenom, albeit in low titers. Fucoidan, a natural sulfated polysaccharide known to inhibit the toxic effects of some basic snake venom components, was unable to reduce cytotoxicity of Naja venoms. Results emphasize the need of enhancing the immunogenicity of low molecular mass toxins during antivenom production, as well as to search for useful toxin inhibitors which could complement antivenom therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.
Geoffrey K Isbister
Full Text Available 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 concentrations were explored by visual inspection and in model building. There were 75 patients, median age 57 years (40-70 y and 64 (85% were male. 411 antivenom concentration data points were analysed. A two compartment model with zero order input, linear elimination kinetics and a combined error model best described the data. Inclusion of BSV on F and weight as a covariate on V improved the model. Inclusion of pre-antivenom concentrations or different batches on BSV of F did not. Final model parameter estimates were CL,0.078 L h(-1, V,2.2L, Q,0.178 L h(-1 and VP,8.33L. The median half-life of distribution