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Sample records for leiurus quinquestriatus scorpion

  1. Cytotoxic and apoptotic effects of scorpion Leiurus quinquestriatus venom on 293T and C2C12 eukaryotic cell lines

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    M. A. A. Omran

    2003-01-01

    Full Text Available Scorpion venom toxicity is of major concern due to its influence on human activities and public health. The cytotoxicity and apoptosis induced by scorpion L. quinquestriatus venom on two established eukaryotic cell lines (293T and C2C12 were analyzed. Both cultured cell lines were incubated with varying doses (10, 20, and 50 µg/ml of scorpion venom in serum free medium (SFM for 0.5, 1, 2, 4, and 8 hours at 37°C. The percentage of total lactate dehydrogenase (LDH released in the culture during venom incubation was used as an index of cell damage. Control culture was treated with an equal amount of SFM. Cell injury was recognized morphologically and apoptosis was researched by a Fluorescing Apoptosis Detection System using the principle of TUNEL (TdT-mediated dUTP Nick-End Labelling assay and confirmed by another assay concerning nuclear DNA staining with DAPI stain. Cytotoxicity was remarkable and cell survival highly reduced at the highest tested concentration (50 µg/ml. These effects were rapid and observed within 30 minutes. The apparent initial damage to the nucleus and lysis of the plasmalemma and/or organelle membranes, which was evident by a significant increase in cytosolic LDH release, suggested that this toxin acts at the membrane level. The morphological changes that occurred in apoptotic cells include condensation and compartmentalization of nuclear and cytoplasmic materials into structurally preserved membrane-bound fragments or blebs. The cytotoxic effects are dose and time dependent and cell death by apoptosis was more characteristic of 293T cells than C2C12 cells. The apoptotic effects were more prominent and clear in the early stages of toxicity, while other forms of cell damage such as swelling, rupture, and/or necrosis occurred at later stages.

  2. The effects of a sodium and a calcium channel blocker on lethality of mice injected with the yellow scorpion (Leiurus quinquestriatus venom

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    A. R. Al-Shanawani

    2005-06-01

    Full Text Available Scorpion venom toxins generally produce similar effects by mainly acting on sodium channels, and to a lesser extent, on potassium, calcium, and chloride channels. This leads to increased release of neurotransmitters and mediators, resulting in a cascade of pathological events, involving the central nervous system, the autonomic nervous system, the cardiovascular and the respiratory system, eventually leading to death. The objective of this paper was to discover whether a sodium channel blocker, lidocaine, or a calcium channel blocker, verapamil, would prolong the survival of mice injected with the venom from the common yellow scorpion Leiurus quinquestriatus quinquestriatus (LQQ. For this purpose, mice were divided into 2 groups, each injected with a different venom dose (250 or 300 µg.kg-1, s.c.. Subgroups (n=10 from each group were given venom alone; different doses of lidocaine (4, 10, 15, or 20 mg.kg-1; or several doses of verapamil (0.01, 0.03, 0.1, 0.3, or 1 mg.kg-1. All doses of lidocaine and verapamil were intravenously administered 3 minutes before, 1, 5, and 15 minutes after venom injection. Percent surviving after 24 hours was recorded in addition to the time of death. In general, lidocaine significantly prolonged survival at the dose of 10 mg.kg-1 (P<0.05 and P<0.01, versus low and high dose of venom, respectively or 15 mg.kg-1 (P<0.01 and P<0.001, versus low and high dose of venom, respectively; Covariance Wilcoxon survival statistics, especially when injected before the venom or in the early stages of envenomation. On the other hand, in all doses administered, verapamil was either toxic or showed non-significant results. Lidocaine, the sodium channel blocker, appears to play an important role in the protection from lethality of mice injected with LQQ venom, and significantly prolonged the survival time of mice whether injected before or in the early stages of envenomation.

  3. Effect of selected anti-inflammatory drugs on the lethal actions of Leiurus quinquestriatus venom

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    N. A. Abdoon

    2006-01-01

    Full Text Available The cumulative actions of scorpion neurotoxins are complex and may be traced to activation of different ion channels with subsequent release of various transmitters and modulators including inflammatory mediators. This could lead to various pathological manifestations such as acute respiratory distress syndrome (ARDS, systemic inflammatory response syndrome (SIRS, and multiple organ failure (MOF. Several approaches have been advocated to treat the multitude of scorpion-venom-elicited pathological changes. However, few have tried to combat the venom-induced effects on the inflammatory process, which manifest as ARDS, SIDS and MOF. Thus, the aim of this study was to determine the capability of inhibitors of different steps of the inflammatory sequence of events in scorpion envenomation to ameliorate the detrimental action of the venom and prolong survival of mice injected with Leiurus quinquestriatus quinquestriatus (LQQ venom. Animals were divided into groups (n = 10 and given montelukast (10 or 20 mg.kg-1, orally, hydrocortisone (5 or 10 mg.kg-1, intravenously or indomethacin (10 or 20 mg kg-1, intravenously. Then, all animals were subcutaneously injected with either 0.25 or 0.3 mg.kg-1 LQQ venom. Signs and symptoms of envenomation were recorded and survival percentages after 24 hours as well as survival time were determined in each group. To analyze data, we utilized Covariance Wilcoxon survival statistics and survival distribution curves. In general, when compared to venom alone, administration of montelukast (p<0.001, hydrocortisone (p<0.05 and indomethacin (p<0.05 prolonged survival time and increased the percentage of surviving animals per group, with montelukast exhibiting the greatest protecting power. Thus, anti-inflammatory drugs may play an important role in protection against the lethal effects of scorpion venoms.

  4. A newly described scorpion species, Leiurus abdullahbayrami (Scorpion: Buthidae, and the lethal potency and in vivo effects of its venom

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    O Ozkan

    2011-01-01

    Full Text Available Currently, medically significant scorpion species belong to the Buthidae family and are represented by the genera Androctonus, Buthus, Mesobuthus, Hottentotta, Parabuthus, Tityus, Centruroides, Leiurus. Although Leiurus was originally considered a monotypic genus, four additional species have since been described. Leiurus abdullahbayrami (previously identified as L. quinquestriatus in Turkey was classified as a new Leiurus species. This is the first report conducted on the lethality and biologic effects of L. abdullahbayrami scorpion venom in mice. In this study, the electrophoretic protein pattern of its venom was also determined. Two protein bands with molecular masses of 4 and 6 kDa were more strongly detected than other protein bands in the venom sample. Electrophoresis showed that L. abdullahbayrami scorpion venom possesses both short- and long-chain neurotoxins. The median lethal dose of this venom was found to be 0.19 mg/kg by subcutaneous (SC injection in mice. Animals experimentally envenomed with L. abdullahbayrami venom exhibited hyperexcitability, agitation, aggressive behavior, squeaking and fighting, tachypnea, weakness, convulsions, and death due to cardiac and respiratory failure. In further studies, the potency of antivenom should be investigated in relation to the scorpion venom. Molecular and pharmacological studies are also required to identify and characterize L. abdullahbayrami scorpion venom.

  5. Protective effects of the antioxidant Ginkgo biloba extract and the protease inhibitor aprotinin against Leiurus quinquestriatus venom-induced tissue damage in rats

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    A. J. Fatani

    2006-04-01

    Full Text Available Oxidative stress and proteases have been implicated in several diseases and extensive evidence indicates that antioxidants and protease inhibitors help prevent organ functional damage. Leiurus quinquestriatus (LQQ scorpion venom causes cellular injuries that may lead to multiple organ failure. Thus, the capability of the antioxidant "natural standardized extract of Gingko biloba leaves (Gin, EGb 761" and the non-selective protease inhibitor, aprotinin, in ameliorating venom-induced biochemical alterations indicative of cellular injury and oxidative stress was studied to determine their effectiveness in protecting rats from venom-evoked cellular damages. Thus, in this study, rats were treated with LQQ venom (0.3mg.kg-1, subcutaneously alone or after Gin (150mg.kg-1, orally, daily for 2 weeks before venom and/or aprotinin (Apr, 46000 KIU.kg-1, intraperitoneally, 30 min before venom. Control groups were injected with saline or treatment modalities. Lungs and hearts were excised after decapitating rats (n=8/group 60 min after venom injection and the following activities were measured: reduced glutathione (GSH, malondialdehyde (MDA - an index of lipid peroxidation, glutathione peroxidase (GPx, glucose-6-phosphate dehydrogenase (G6PD, and lactate dehydrogenase (LDH. Our findings demonstrate that LQQ venomsignificantly elevated GSH (p<0.05 vs. control, MDA (p<0.05, G6PD (p<0.05, and LDH activities (p<0.001 in hearts of envenomed rats. The venom also elevated MDA (p<0.05 vs. control and reduced GSH and GPx (p<0.05 in the lungs of envenomed rats. In general, pretreatment with EGb761 attenuated LQQ venom-evoked increases in GSH (p<0.05 vs. venom, MDA in rat hearts and lungs (p<0.05 vs. venom, plus LDH in the heart (p<0.01. Aprotinin alone significantly reduced the venom-elicited increase in G6PD and LDH activities and the decrease in GPx levels (p<0.05. In general, these protective effects of EGb761 on GSH, MDA (p<0.01 vs. venom and LDH (p<0.001 in the

  6. The histological changes in the liver, lung and kidney after scorpion poisoning (Buthus quinquestriatus).

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    Nawar, N N; Shoukri, N A; Hanna, M M

    1979-06-01

    The effect of sublethal doses of Buthus quinquestriatus on the hepatic vascular bed and hepatic parenchyma were studied. The main effect of the venom was primarily on the vascular bed of the liver as manifested by dilatation of branches of the hepatic artery, portal vein together with intravascular thrombi and subcapsular haemorrhages. Apart from mild hydropic degeneration some cells of the hepatic parenchyma showed focal necrosis and Kupffer cells were frequently hypertrophied and contained pigment. In the lung, dilated thrombosed vessels were observed. In the kidney, the vessels showed the smae changes. The epithelial and endothelial cells of the glomeruli appeared normal except for slight swelling with intact basement membrane. The tubular cells were swollen with increased granularity and attenuation of their tubular lumen, a picture compatible with hydropic degeneration. The possible mechanisms in inducing such lesions were discussed.

  7. Simultaneous modifications of sodium channel gating by two scorpion toxins.

    OpenAIRE

    1982-01-01

    The effects of purified scorpion toxins from two different species on the kinetics of sodium currents were evaluated in amphibian myelinated nerves under voltage clamp. A toxin from Leiurus quinquestriatus slowed and prevented sodium channel inactivation, exclusively, and a toxin from Centruroides sculpturatus Ewing reduced transient sodium currents during a maintained depolarization, and induced a novel inward current that appeared following repolarization, as previously reported by Cahalan ...

  8. In vivo and in vitro effects of scorpion venoms in Turkey: a mini-review

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    S Adiguzel

    2010-01-01

    Full Text Available Scorpion stings constitute a common type of accident in Turkey due to the geographic location, climate and socioeconomic structure of this country. Moreover, envenomation cases are considered a public health problem throughout Turkey. Based on data in the literature, the main clinical features of scorpion envenomations are defined as systemic manifestations including sweating, hypertension and vomiting, and among prominent causes of death are cardiorespiratory manifestations, toxic myocarditis and pulmonary edema. The most important health-threatening scorpions found in Turkey are: Androctonus crassicauda, Leiurus quinquestriatus, Mesobuthus gibbosus and Mesobuthus eupeus, all of which belong to the Buthidae family. This study indicates that there is no data related to venom toxicity and in vivo effects of other scorpions found in Turkey - such as Mesobuthus caucasicus, Mesobuthus nigrocinctus and Hottentotta saulcyi - and that further research should be performed to determine their health effects.

  9. Light and transmission electron microscopical changes associated with Leiurus quinqestriatus venom in rabbits

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    Salah H. Afifi

    2016-03-01

    Full Text Available Thirty California female rabbits were obtained from the Animal Care Center, College of Agriculture, South Valley University and acclimated to laboratory conditions for one week. The Leiurus quinquestriatus (LQ venom was collected from mature scorpions by electrical stimulation of the telson. A single dose of crude venom of 0.4 ml/kg (diluted in normal saline with a ratio of 1:1 was injected into a peripheral ear vein. The lungs, brains, hearts, kidneys, were sampled and fixed in 10% formalin from rabbits sacrificed at zero, 30 minutes, 1hr, and 4hrs, post-envenomation (three animals at each sacrifice. Respiratory distress and neurological manifestations were the main clinical signs. Congestion of the lungs was started at one hour postenvenomation. Vascular changes including hyperemia and hemorrhage were also observed till 24 hours post-envenomation. The main histopathological changes of the lungs were edema, hemorrhage, emphysema, and eosinophilic bronchitis. Transmission electron microscopy revealed several eosinophils with abundant granules and breakdown of their membranes suggesting degranulation. The cerebrum showed malacia and edema. Myocardial damage expressed by focal area of myolysis at half-hour post-envenomation and interstitial edema by at 1, and 4 hour post-envenomation was also evident. In conclusion, scorpion venom induced consistent and relevant histopathological changes in all examined organs.

  10. Photoaffinity labeling of alpha- and beta- scorpion toxin receptors associated with rat brain sodium channel.

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    Darbon, H; Jover, E; Couraud, F; Rochat, H

    1983-09-15

    Azido nitrophenylaminoacetyl [125I]iodo derivative of toxin II from Centruroides suffusus suffusus, a beta-toxin, and azido nitrophenylaminoacetyl [125I]iodo derivative of toxin V from Leiurus quinquestriatus quinquestriatus, an alpha-toxin, have been covalently linked after binding to their receptor sites that are related to the voltage sensitive sodium channel present in rat brain synaptosomes. Both derivatives labeled two polypeptides of 253000 +/- 20000 and 35000 +/- 2000 mol. wt. Labeling was blocked for each derivative by a large excess of the corresponding native toxin but no cross inhibition was obtained. These results suggest that both alpha - and beta - scorpion toxin receptors are located on or near the same two membrane polypeptides which may be part of the voltage dependent sodium channel.

  11. Autonomic effects of some scorpion venoms and toxins.

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    Gwee, Matthew C E; Nirthanan, Selvanayagam; Khoo, Hoon-Eng; Gopalakrishnakone, Ponnampalam; Kini, R Manjunatha; Cheah, Li-Sam

    2002-09-01

    1. The autonomic effects of venoms and toxins from several species of scorpions, including the Indian red scorpion Mesobuthus tamulus, the Chinese scorpion Buthus martensi Karsch and the Israeli scorpion Leiurus quinquestriatus quinquestriatus, all belonging to Buthidae, and the Asian black scorpions Heterometrus longimanus and Heterometrus spinifer, belonging to Scorpionidae, are reviewed. 2. The effects of the venoms of M. tamulus and L. q. quinquestriatus on noradrenergic and nitrergic transmission in the rat isolated anococcygeus muscle revealed that both venoms mediated their pharmacological effects via a prejunctional mechanism involving the activation of voltage-sensitive sodium channels with consequent release of neurotransmitters that mediate target organ responses, similar to the effects mediated by other alpha-scorpion toxins. 3. Two new toxins, Makatoxin I and Bukatoxin, were purified to homogeneity from the venom of B. martensi Karsch. Determination of their complete amino acid sequences confirmed that both toxins belonged to the class of alpha-scorpion toxins. The effects of both toxins on noradrenergic and nitrergic transmission in the rat anococcygeus muscle provided firm evidence that their pharmacological actions also closely resembled those mediated by other alpha-scorpion toxins on neuronal voltage-sensitive sodium channels. 4. The venoms of H. longimanus and H. spinifer were found to have high concentrations of noradrenaline (1.8 +/- 0.3 mmol/L) and relatively high concentrations of acetylcholine (79.8 +/- 1.7 micromol/L) together with noradrenaline (146.7 +/- 19.8 micromol/L), respectively, which can account for their potent direct cholinergic and noradrenergic agonist actions in the rat anococcygeus muscle. 5. Our studies confirmed that the rat anococcygeus muscle is an excellent nerve-smooth muscle preparation for investigating the effects of bioactive agents on noradrenergic and nitrergic transmission, as well as the direct agonist actions

  12. Investigation of in vivo potential of scorpion venom against skin tumorigenesis in mice via targeting markers associated with cancer development

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    Al Asmari AK

    2016-10-01

    Full Text Available Abdulrahman K Al Asmari, Abdul Quaiyoom Khan Research Centre, Prince Sultan Military Medical City, Riyadh, Saudi Arabia Abstract: Cancer is the leading cause of morbidity and mortality all over the world in spite of the advances made in its management. In this study, we investigated the in vivo antitumorigenic potential of the venom obtained from a medically important scorpion species Leiurus quinquestriatus on chemically induced skin cancer in mice. Animals were divided into five groups, with 13 animals in each group. All the treatments were given topically on the shaved dorsal surface of the skin. Animals in Group 1 received vehicle only (0.2 mL acetone. Moreover, 7,12-dimethylbenz[a]anthracene (DMBA, 400 nmol per mouse was applied to all the animals in the remaining four groups. After 1 week, different concentrations of venom (17.5 µg, 35 µg, and 52.5 µg per animal were applied to each animal in the Groups III–V. Thirty minutes after the application of venom, croton oil was applied on the same position where venom was administered to the animals of Groups III–V. Animals in Group II were treated as the positive control (without venom and received croton oil as in Groups III–V. The findings of this study revealed that venom extract of L. quinquestriatus inhibits DMBA + croton oil-induced mouse skin tumor incidence and tumor multiplicity. Venom treatment also decreased the expression of proinflammatory cytokines. Immunohistochemistry results showed a downregulation of the expression of molecular markers such as Ki-67, nuclear factor kappa-B, cyclooxygenase-2, B-cell lymphoma-2, and vascular endothelial growth factor, in venom-treated animals. Our findings suggest that the venom of L. quinquestriatus possesses in vivo anticancer potential and may be used in the development of anticancer molecules. Keywords: Leiurus quinquestriatus, skin cancer, apoptosis, immunosuppression

  13. Scorpions

    Science.gov (United States)

    ... Scorpion venom contains the poison. Where Found This venom is found in scorpions and related species. Scorpion stings kill more people around the world than any other animal, except snakes (from snake bites). However, most varieties of North ...

  14. A chimeric scorpion alpha-toxin displays de novo electrophysiological properties similar to those of alpha-like toxins.

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    Bouhaouala-Zahar, Balkiss; Benkhalifa, Rym; Srairi, Najet; Zenouaki, Ilhem; Ligny-Lemaire, Caroline; Drevet, Pascal; Sampieri, François; Pelhate, Marcel; El Ayeb, Mohamed; Ménez, André; Karoui, Habib; Ducancel, Frédéric

    2002-06-01

    BotXIV and LqhalphaIT are two structurally related long chain scorpion alpha-toxins that inhibit sodium current inactivation in excitable cells. However, while LqhalphaIT from Leiurus quinquestriatus hebraeus is classified as a true and strong insect alpha-toxin, BotXIV from Buthus occitanus tunetanus is characterized by moderate biological activities. To assess the possibility that structural differences between these two molecules could reflect the localization of particular functional topographies, we compared their sequences. Three structurally deviating segments located in three distinct and exposed loops were identified. They correspond to residues 8-10, 19-22, and 38-43. To evaluate their functional role, three BotXIV/LqhalphaIT chimeras were designed by transferring the corresponding LqhalphaIT sequences into BotXIV. Structural and antigenic characterizations of the resulting recombinant chimera show that BotXIV can accommodate the imposed modifications, confirming the structural flexibility of that particular alpha/beta fold. Interestingly, substitution of residues 8-10 yields to a new electrophysiological profile of the corresponding variant, partially comparable to that one of alpha-like scorpion toxins. Taken together, these results suggest that even limited structural deviations can reflect functional diversity, and also that the structure-function relationships between insect alpha-toxins and alpha-like scorpion toxins are probably more complex than expected.

  15. Turkish scorpion Buthacus macrocentrus: general characterization of the venom and description of Bu1, a potent mammalian Na⁺-channel α-toxin.

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    Caliskan, F; Quintero-Hernández, V; Restano-Cassulini, R; Batista, C V F; Zamudio, F Z; Coronas, F I; Possani, L D

    2012-03-01

    The venom of the scorpion Buthacus macrocentrus of Turkey was fractionated by high performance liquid chromatography (HPLC) and its mass finger print analysis was obtained by spectrometry. More than 70 different fractions were obtained, allowing the determination of the molecular masses of at least 60 peptides ranging between 648 and 44,336 Da. The venom is enriched with peptides containing molecular masses between 3200-4500 Da, and 6000-7500 Da. They very likely correspond to K⁺-channel and Na⁺-channel specific peptides, respectively, as expected from venoms of scorpions of the family Buthidae, already determined for other species. The major component obtained from HPLC was shown to be lethal to mice and was further purified and characterized. It contains 65 amino acid residues maintained closely packed by 4 disulfide bridges, and shows a molecular weight of 7263 Da. Additionally, a cDNA from the venomous glands of this scorpion was used in conjunction with sequence data from Edman degradation and mass spectrometry for cloning the gene that codes for Bu1 as we named this toxin. This gene codes for a 67 amino acid residues peptide, where the two last are eliminated post-translationally for production of an amidated C-terminal arginine. Its sequence is closely related to toxins from the species Leiurus quinquestriatus, as revealed by a phylogenetic tree analysis. Electrophysiological results conducted with Bu1 using patch-clamp techniques indicate that it modifies the Na⁺ currents, in a similar way as other well known α-scorpion toxins. These results support the conclusion that this species of scorpions is dangerous to humans, having an epidemiological interest for the country.

  16. Structural mapping of the voltage-dependent sodium channel. Distance between the tetrodotoxin and Centruroides suffusus suffusus II beta-scorpion toxin receptors.

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    Darbon, H; Angelides, K J

    1984-05-25

    A 7- dimethylaminocoumarin -4-acetate fluorescent derivative of toxin II from the venom of the scorpion Centruroides suffusus suffusus (Css II) has been prepared to study the structural, conformational, and cellular properties of the beta-neurotoxin receptor site on the voltage-dependent sodium channel. The derivative retains high affinity for its receptor site on the synaptosomal sodium channel with a KD of 7 nM and site capacity of 1.5 pmol/mg of synaptosomal protein. The fluorescent toxin is very environmentally sensitive and the fluorescence emission upon binding indicates that the Css II receptor is largely hydrophobic. Binding of tetrodotoxin or batrachotoxin does not alter the spectroscopic properties of bound Css II, whereas toxin V from Leiurus quinquestriatus effects a 10-nm blue shift to a more hydrophobic environment. This is the first direct indication of conformational coupling between these separate neurotoxin receptor sites. The distance between the tetrodotoxin and Css II scorpion toxin receptors on the sodium channel was measured by fluorescence resonance energy transfer. Efficiencies were measured by both donor quenching and acceptor-sensitized emission. The distance between these two neurotoxin sites is about 34 A. The implications of these receptor locations together with other known molecular distances are discussed in terms of a molecular structure of the voltage-dependent sodium channel.

  17. Scorpion stings in Turkey: epidemiological and clinical aspects between the years 1995 and 2004 Picadas de escorpião na Turquia: aspectos epidemiológicos e clínicos entre os anos de 1995 e 2004

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    Yıldırım Cesaretli

    2010-08-01

    Full Text Available The most important health-threatening scorpions found in Turkey are; Androctonus crassicauda, Leiurus quinquestriatus, Mesobuthus gibbosus and M. eupeus species, all of which belong to the Buthidae family. The epidemiological and clinical findings of scorpion stings in Turkey were evaluated between the years 1995 and 2004 based on data recorded in the National Poison Information Center (NPIC. A total of 930 cases were recorded. The cases mostly occurred in the month of July. The gender distribution was 50.22% female and 45.48% male. It was shown that the 20-29 age group presented more scorpion stings. Most of the stings occurred in Central Anatolia and Marmara regions of Turkey. Patients at the hospital showed signs of localized (pain, hyperemia, edema and numbness and systemic effects (hyperthermia, nausea and vomiting, tachycardia, shivering and lethargy but no lethality was notified. According to records, 33% of the poisoned patients were treated with antivenin in healthcare facilities.Os mais importantes escorpiões que comprometem a saúde na Turquia são: Androctonus crassicauda, Leiurus quinquestriatus, Mesobuthus gibbosus e M. eupeus, todos eles pertencentes à família Buthidae. Os achados clínicos e epidemiológicos da picada de escorpiões na Turquia foram avaliados no período entre os anos de 1995 a 2004 baseados em dados do Centro Nacional de Informações de Envenenamentos (NPIC. Foram registrados 930 casos que ocorreram principalmente no mês de julho. A distribuição por sexo foi 50,22% femininos e 45,48% masculinos. Demonstrou-se que o grupo etário de 20 a 29 anos apresentou maior número de picadas de escorpião. A maior parte das picadas ocorreu na Anatólia Central e na região de Marmara, na Turquia. Os pacientes hospitalizados mostraram sinais localizados (dor, hiperemia, edema e confusão mental e sistêmicos (hipertermia, náusea e vômitos, taquicardia, arrepios de frio e letargia, mas não houve notificação de

  18. A scorpion venom neurotoxin paralytic to insects that affects sodium current inactivation: Purification, primary structure, and mode of action

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    Eitan, M.; Fowler, E.; Herrmann, R.; Duval, A.; Pelhate, M.; Zlotkin, E. (Hebrew Univ., Jerusalem (Israel))

    1990-06-26

    A new toxin, Lqh alpha IT, which caused a unique mode of paralysis of blowfly larvae, was purified from the venom of the scorpion Leiurus quinquestriatus hebraeus, and its structural and pharmacological properties were compared to those of three other groups of neurotoxins found in Buthinae scorpion venoms. Like the excitatory and depressant insect-selective neurotoxins, Lqh alpha IT was highly toxic to insects, but it differed from these toxins in two important characteristics: (a) Lqh alpha IT lacked strict selectivity for insects; it was highly toxic to crustaceans and had a measurable but low toxicity to mice. (b) It did not displace an excitatory insect toxin, 125I-AaIT, from its binding sites in the insect neuronal membrane; this indicates that the binding sites for Lqh alpha IT are different from those shared by the excitatory and depressant toxins. However, in its primary structure and its effect on excitable tissues, Lqh alpha IT strongly resembled the well-characterized alpha scorpion toxins, which affect mammals. The amino acid sequence was identical with alpha toxin sequences in 55%-75% of positions. This degree of similarity is comparable to that seen among the alpha toxins themselves. Voltage- and current-clamp studies showed that Lqh alpha IT caused an extreme prolongation of the action potential in both cockroach giant axon and rat skeletal muscle preparations as a result of the slowing and incomplete inactivation of the sodium currents. These observations indicate that Lqh alpha IT is an alpha toxin which acts on insect sodium channels.

  19. In vitro determination of the efficacy of scorpion venoms as anti-cancer agents against colorectal cancer cells: a nano-liposomal delivery approach.

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    Al-Asmari, Abdulrahman K; Ullah, Zabih; Al Balowi, Ali; Islam, Mozaffarul

    2017-01-01

    The use of liposomes in biological and medicinal sciences is a relatively new approach. The liposomal strategy greatly depends on the technological advancement in the formation of vesicles of various sizes and properties. In the current study, we encapsulated the venoms obtained from medically important scorpions such as Androctonus bicolor (AB), Androctonus crassicauda (AC), and Leiurus quinquestriatus (LQ). To begin with, our first and foremost aim was to prepare biocompatible and biodegradable nanovesicles. Additionally, we intended to enhance the anti-cancer potential of these encapsulated venoms. The liposomal venoms were prepared by rehydration and dehydration methods. Morphology, particle size, and size distribution of the liposomes were examined by scanning electron microscope (SEM), transmission electron microscope (TEM), and Zetasizer. We found that the prepared liposomes had a smooth surface and a spherical/ovoid shape and existed mainly as single unilamellar vesicles (SUVs). Furthermore, the liposomal formulation of all three venoms exhibited excellent stability and good encapsulation efficiency (EE). Additionally, the anti-cancer potential of the encapsulated venoms was also evaluated on a colorectal cancer cell line (HCT-8). The venom-loaded liposomes showed elevated anti-cancer properties such as low rate of cell survival, higher reactive oxygen species (ROS) generation, and enhancement in the number of apoptotic cells. In addition to this, cell cycle analysis revealed G0/G1 enrichment upon venom treatment. The effect of treatment was more pronounced when venom-liposome was used as compared to free venom on the HCT-8 cell line. Furthermore, we did not observe any interference of liposomal lipids used in these preparations on the progression of cancer cells. Considering these findings, we can conclude that the encapsulated scorpion venoms exhibit better efficacy and act more vigorously as an anti-cancer agent on the colorectal cancer cell line when

  20. Functional Analysis of a Gene Encoding a Chlorotoxin-like Peptide Derived from Scorpion Toxin%东亚钳蝎氯毒素BmKCT的表达和功能鉴定

    Institute of Scientific and Technical Information of China (English)

    杨锐; 彭方; 刘辉; 曹志贱; 李文鑫; 毛歆; 蒋达和

    2005-01-01

    从中国东亚钳蝎Buthus martensii Karsch的毒腺cDNA文库中分离得到了一个编码毒素蛋白多肽(命名为BmKCT)前体的全长cDNA序列.该毒素多肽与已报道的氯毒素(chlorotoxin)高度同源,其蛋白质一级序列有68%的同源性.为了鉴定BmKCT的生物学功能,通过pGEX系统成功地表达了BmKCT,并用GST亲和层析和凝胶过滤的方法获得了纯化的重组BmKCT毒素蛋白(rBmKCT).通过膜片钳实验,记录了rBmKCT对人脑星型胶质瘤细胞(gliomas cell)表面的氯离子通道电流的作用.结果显示,BmKCT可以显著抑制人脑星型胶质瘤细胞表面的氯离子通道电流,并且这种抑制作用在一定程度上是可逆的.实验证明,在细胞水平上,BmKCT是一种新的短链氯离子通道抑制剂.%A full-length cDNA sequence encoding for the precursor of a venom peptide (named BmKCT) with homology to chlorotoxin has been isolated from a cDNA library made from the venom glands of the Chinese Scorpion Buthus martensii Karsch. The sequence of BmKCT is similar (68 % identities) to that of chlorotoxin isolated from Leiurus quinquestriatus quinquestriatus. To understand the biological function of BmKCT, this peptide was expressed using pGEX expression system and purified using GST affinity column and gel filtration.Whole cell patch-clamping recording showed that BmKCT could significantly inhibit chloride currents of gliomas cells, and the inhibitory effect was reversible. These results suggested that BmKCT might belong to the class of short chain toxins blocking the chloride ion channels.

  1. NMR analysis of interaction of LqhalphaIT scorpion toxin with a peptide corresponding to the D4/S3-S4 loop of insect para voltage-gated sodium channel.

    Science.gov (United States)

    Schnur, Einat; Turkov, Michael; Kahn, Roy; Gordon, Dalia; Gurevitz, Michael; Anglister, Jacob

    2008-01-22

    Voltage-gated sodium channels (Navs) are large transmembrane proteins that initiate action potential in electrically excitable cells. This central role in the nervous system has made them a primary target for a large number of neurotoxins. Scorpion alpha-neurotoxins bind to Navs with high affinity and slow their inactivation, causing a prolonged action potential. Despite the similarity in their mode of action and three-dimensional structure, alpha-toxins exhibit great variations in selectivity toward insect and mammalian Navs, suggesting differences in the binding surfaces of the toxins and the channels. The scorpion alpha-toxin binding site, termed neurotoxin receptor site 3, has been shown to involve the extracellular S3-S4 loop in domain 4 of the alpha-subunit of voltage-gated sodium channels (D4/S3-S4). In this study, the binding site for peptides corresponding to the D4/S3-S4 loop of the para insect Nav was mapped on the highly insecticidal alpha-neurotoxin, LqhalphaIT, from the scorpion Leiurus quinquestriatus hebraeus, by following changes in the toxin amide 1H and 15N chemical shifts upon binding. This analysis suggests that the five-residue turn (residues LqK8-LqC12) of LqhalphaIT and those residues in its vicinity interact with the D4/S3-S4 loop of Nav. Residues LqR18, LqW38, and LqA39 could also form a patch contributing to the interaction with D4/S3-S4. Moreover, a new bioactive residue, LqV13, was identified as being important for Nav binding and specifically for the interaction with the D4/S3-S4 loop. The contribution of LqV13 to NaV binding was further verified by mutagenesis. Future studies involving other extracellular regions of Navs are required for further characterization of the structure of the LqhalphaIT-Navs binding site.

  2. Scorpions and scorpionism in Iran's central desert.

    Science.gov (United States)

    Nejati, Jalil; Saghafipour, Abedin; Mozaffari, Ehsan; Keyhani, Amir; Jesri, Nahid

    2017-02-01

    Venomous scorpions have extreme importance in field of medicine and public health. This descriptive - analytic study was done to identify scorpion fauna, their ecological aspects as well as scorpionism for risk management and prevention of this health problem in Iran's central desert. Four urban and fifteen rural areas with various climates and topography locations were selected for monthly scorpion collection through a randomly cluster sampling in 2013. The clinical data was obtained from questionnaires provided in 2009-2014. Totally, 1481 scorpion sting cases were recorded. The majority were treated less than 6h after the sting. Statistical tests showed significant difference between season, scorpion's color, living place of patients and scorpionism cases. Plain areas had the most occurrence of scorpionism followed by foothills. Moreover, 311 scorpion samples belonged to 7 species of Buthidae were collected. Mesobuthus eupeus was the dominant species in both rural and urban areas. Most of the collected samples were from indoors, yards and around the houses. The most scorpion activity was recorded in the summer. The studied areas had rich scorpion fauna due to various climates and topography locations. Scorpion stings can be important and fatal in this area, particularly in the plain regions with semi-desert climate. An investigation for assessment of peoples' awareness on prevention methods of scorpionism and also the determination and the assessment of effective factors on reducing the elapsed time between scorpion stings and receiving medical care are here recommended.

  3. Mapping of scorpion toxin receptor sites at voltage-gated sodium channels.

    Science.gov (United States)

    Gurevitz, Michael

    2012-09-15

    Scorpion alpha and beta toxins interact with voltage-gated sodium channels (Na(v)s) at two pharmacologically distinct sites. Alpha toxins bind at receptor site-3 and inhibit channel inactivation, whereas beta toxins bind at receptor site-4 and shift the voltage-dependent activation toward more hyperpolarizing potentials. The two toxin classes are subdivided to distinct pharmacological groups according to their binding preferences and ability to compete for the receptor sites at Na(v) subtypes. To elucidate the toxin-channel surface of interaction at both receptor sites and clarify the molecular basis of varying toxin preferences, an efficient bacterial system for their expression in recombinant form was established. Mutagenesis accompanied by toxicity, binding and electrophysiological assays, in parallel to determination of the three-dimensional structure using NMR and X-ray crystallography uncovered a bipartite bioactive surface in toxin representatives of all pharmacological groups. Exchange of external loops between the mammalian brain channel rNa(v)1.2a and the insect channel DmNa(v)1 highlighted channel regions involved in the varying sensitivity to assorted toxins. In parallel, thorough mutagenesis of channel external loops illuminated points of putative interaction with the toxins. Amino acid substitutions at external loops S1-S2 and S3-S4 of the voltage sensor module in domain II of rNa(v)1.2a had prominent impact on the activity of the beta-toxin Css4 (from Centruroides suffusus suffusus), and substitutions at external loops S1-S2 and S3-S4 of the voltage sensor module in domain IV affected the activity of the alpha-toxin Lqh2 (from Leiurus quinquestriatus hebraeus). Rosetta modeling of toxin-Na(v) interaction using the voltage sensor module of the potassium channel as template raises commonalities in the way alpha and beta toxins interact with the channel. Css4 interacts with rNa(v)1.2a at a crevice between S1-S2 and S3-S4 transmembrane segments in domain

  4. Emergent management of scorpion sting.

    Science.gov (United States)

    Kluz-Zawadzka, Jolanta; Hartman-Ksycińska, Anna; Lewandowski, Bogumił

    2014-01-01

    Scorpionism (syndrome of scorpion stings) is an important public health problem in many regions of the world, not only in tropics and subtropics. As scorpions may be unintentionally transported to any place in the world and keeping scorpions as pets is becoming more popular, scorpion stings occur also in Poland. Therefore, health professionals should have the knowledge on the management of scorpion stings. This article discusses a case who was stung by scorpion and proposes an algorithm of management with such patients.

  5. Scorpion fish sting

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002849.htm Scorpion fish sting To use the sharing features on this page, please enable JavaScript. Scorpion fish are members of the family Scorpaenidae, which ...

  6. Insects and Scorpions

    Science.gov (United States)

    ... and Products Programs Contact NIOSH NIOSH INSECTS AND SCORPIONS Recommend on Facebook Tweet Share Compartir Stinging or biting insects or scorpions can be hazardous to outdoor workers. Stinging or ...

  7. Cerebrovascular manifestations following scorpion sting

    OpenAIRE

    Nataraja P; Naveen Prasad SV; Obulareddy G; Anil Ch; Naveen T; Vengamma B

    2016-01-01

    Scorpion sting is a common clinical problem in Rayalaseema area of Andhra Pradesh State in India. Clilnical presentation of scorpion envenomation can range from mild local pain to systemic manifestations involving almost all systems. Cerebrovascular manifestations of scorpion sting have been sparsely documented. We report two cases who presented with ischaemic stroke and haemorrhagic stroke following scorpion sting.

  8. Hey! A Scorpion Stung Me!

    Science.gov (United States)

    ... dientes Video: Getting an X-ray Hey! A Scorpion Stung Me! KidsHealth > For Kids > Hey! A Scorpion ... Ay! ¡Me ha picado un escorpión! What's a Scorpion? A scorpion is part of the arachnid family, ...

  9. Scorpion image segmentation system

    Science.gov (United States)

    Joseph, E.; Aibinu, A. M.; Sadiq, B. A.; Bello Salau, H.; Salami, M. J. E.

    2013-12-01

    Death as a result of scorpion sting has been a major public health problem in developing countries. Despite the high rate of death as a result of scorpion sting, little report exists in literature of intelligent device and system for automatic detection of scorpion. This paper proposed a digital image processing approach based on the floresencing characteristics of Scorpion under Ultra-violet (UV) light for automatic detection and identification of scorpion. The acquired UV-based images undergo pre-processing to equalize uneven illumination and colour space channel separation. The extracted channels are then segmented into two non-overlapping classes. It has been observed that simple thresholding of the green channel of the acquired RGB UV-based image is sufficient for segmenting Scorpion from other background components in the acquired image. Two approaches to image segmentation have also been proposed in this work, namely, the simple average segmentation technique and K-means image segmentation. The proposed algorithm has been tested on over 40 UV scorpion images obtained from different part of the world and results obtained show an average accuracy of 97.7% in correctly classifying the pixel into two non-overlapping clusters. The proposed 1system will eliminate the problem associated with some of the existing manual approaches presently in use for scorpion detection.

  10. Scorpions: a presentation.

    Science.gov (United States)

    Goyffon, Max; Tournier, Jean-Nicolas

    2014-07-21

    Scorpions, at least the species of the family Buthidæ whose venoms are better known, appear as animals that have evolved very little over time. The composition of their venoms is relatively simple as most toxins have a common structural motif that is found in other venoms from primitive species. Moreover, all the scorpion venom toxins principally act on membrane ionic channels of excitable cells. The results of recent works lead to the conclusion that in scorpions there is a close relationship between venomous function and innate immune function both remarkably efficient.

  11. Two types of scorpion receptor sites, one related to the activation, the other to the inactivation of the action potential sodium channel.

    Science.gov (United States)

    Couraud, F; Jover, E; Dubois, J M; Rochat, H

    1982-01-01

    The action of the neurotoxin in Buthinae scorpion venoms (Androctonus, Buthus or Leiurus genera) has been extensively studied. These proteins induce a prolongation of the action potential of nerves and muscles by slowing down inactivation of the sodium channel. Their affinity for their receptor site depends on membrane potential. In the present report we describe a toxin from a Centrurinae scorpion, Centruroides suffusus, which binds rat brain synaptosomes at a receptor site distinct from the Buthinae scorpion site independently of voltage. We name Androctonus-like toxins, alpha-scorpion toxins (alpha-ScTX), and Centruroides-like toxins, beta-scorpion toxins (beta-ScTX). We further report that beta-ScTX induces repetitive firing in frog myelinated nerve fibres by producing an abnormal sodium permeability. The beta-toxin binds specifically to rat brain synaptosomes (Kd = 3 nM) and induces an inhibition of the uptake and a stimulation of the release of GABA at concentrations which are in good agreement with the Kd value. These effects are blocked by tetrodotoxin. The binding site of beta -ScTX is distinct from those of other neurotoxins acting on the sodium channel like tetrodotoxin, alpha-ScTX and veratridine. The alpha-ScTX/beta-ScTX binding site capacities decreases as development of rat brain synaptosomes progresses ; at day 7 after birth, it is 1.1. and at day 39, 0.3.

  12. Scorpion sting nephropathy

    OpenAIRE

    2011-01-01

    Scorpion envenomations are ubiquitous, but nephropathy is a rare manifestation, reported mainly from the Middle East and North Africa. Rapid venom redistribution from blood, delayed excretion from the kidneys, direct toxicity of venom enzymes, cytokine release and afferent arteriolar constriction have been seen in experimental animals. Haemoglobinuria, acute tubular necrosis, interstitial nephritis and haemolytic–uraemic syndrome have been documented in human victims of scorpion envenomation....

  13. Hey! A Scorpion Stung Me!

    Science.gov (United States)

    ... of scorpion, which usually lives in Arizona, New Mexico, and other southwestern states, can kill people. Scorpions ... Ben-Joseph, MD Date reviewed: September 2016 For Teens For Kids For Parents MORE ON THIS TOPIC ...

  14. Scorpion fauna and epidemiological aspects of scorpionism in southeastern Iran

    Institute of Scientific and Technical Information of China (English)

    Jalil Nejati; Ehsan Mozafari; Abedin Saghafipour; Malek Kiyani

    2014-01-01

    Objective: To identify the scorpion fauna and classify the epidemiological aspects of scorpionism in an endemic region, Southeast Iran. Methods: Scorpionism data were collected from health centers and hospitals in Sistan-Baluchestan Province during 2010-2011. Specimens were collected at night, using UV light, between May and October 2012.Results:Five species including Odontobuthus odonturus, Hottentotta (Buthotus) jayakari, Compsobuthus matthiesseni, Scorpio maurus and Orthochirus scrobiculosus are reported for the first time from this area. Androctonus crassicauda was the dominant species. In total, 3638 scorpion sting cases were recorded by health system, the majority of which were females. Stings mostly occurred in July and the age group of 15-24 years presented the highest frequency. Scorpionism decreased during 2011 compared with that in 2010 (68.2%). In total, 246 scorpions were collected from two families (Buthidae and Scorpionidae). Conclusions: Based on the results, scorpionism is a serious health problem in this area and increasing knowledge of residents regarding the prevention methods of scorpion stings is recommended. Additional research on the scorpion fauna, their ecological and molecular variety in this part of the country is needed as well as the correlation between scorpions’ species and the clinical signs and symptoms.

  15. Scorpion sting and hypertensive crisis

    Directory of Open Access Journals (Sweden)

    C. Ratti

    2013-05-01

    Full Text Available BACKGROUND Scorpion stings are very frequent in Centre-South America. The most frequently observed clinical symptoms are: local pain and redness, tachycardia, irritability, hypertensive crisis; but it differs with the scorpion species involved. CLINICAL CASE We describe a scorpion sting in a woman who came back from a holiday in Mexico. Consequently she had a hypertensive crisis treated with furosemide. DISCUSSION The scorpion sting can be very dangerous. There are many species which could be lethal; in these cases, identifying the exact species can be essential to save the patient’s life. The treatment consists of symptomatic measures, support of vital functions and i.v. antivenom.

  16. Clinical update on scorpion envenoming

    Directory of Open Access Journals (Sweden)

    Palmira Cupo

    2015-12-01

    Full Text Available Abstract: Scorpion stings are currently the leading cause of venom-related injury to humans in Brazil and are a significant public health problem globally. Only scorpions of the Tityus genus are of medical importance in Brazil, and Tityus serrulatus is responsible for the most serious envenomations and deaths. The toxic effects of scorpion envenomation are due to a massive release of sympathetic and parasympathetic neurotransmitters; the severity is related to cardiac and hemodynamic changes, with cardiogenic shock and pulmonary edema contributing to the main causes of death. The pathophysiology of cardiac involvement has been discussed for decades and has been attributed to adrenergic discharge and a possible toxic effect of venom on the myocardium, while acute pulmonary edema may have a cardiogenic and/or non-cardiogenic origin. Currently, the clinical data point to catecholamine excess as the cause for reversible scorpion cardiomyopathy . These data include electrocardiographic changes, profiling of cardiac enzymes and troponin I, echocardiographic data with global or regional left ventricle dysfunction, and myocardial perfusion alterations compatible with spasm in the coronary microcirculation. Furthermore, recent data on cardiac magnetic resonance imaging findings, which are similar to those observed for stress-induced cardiomyopathy, have also been linked to catecholamine excess. The efficiency of antivenom serum treatment is controversial in the literature. Our experience in Brazil is that the management of patients with systemic manifestations of scorpion stings is based on three approaches, all of which are extremely important. These include symptomatic treatment, antivenom serum, and cardiorespiratory support.

  17. History of study, updated checklist, distribution and key of scorpions (Arachnida: Scorpiones) from China.

    Science.gov (United States)

    Di, Zhi-Yong; Yang, Zi-Zhong; Yin, Shi-Jin; Cao, Zhi-Jian; Li, Wen-Xin

    2014-01-01

    This review describes the history of taxonomic research on scorpions and provides an updated checklist and key of the scorpions currently known in China. This checklist is based on a thorough review of the extant literatures on scorpion species whose presence has been confirmed in China through field expeditions and examination of scorpion collections, excepting a few members that have no clear distribution or are currently in doubt. Totally, the scorpion fauna of China consists of 53 species and subspecies belonging to 12 genera crossing five families, with 33 species (62.3%) and one genus being recorded as endemic. Additionally, identification key and the distribution of scorpions from China are provided.

  18. Scrotum Injury by Scorpion Sting

    Directory of Open Access Journals (Sweden)

    R Dehghani

    2008-08-01

    Full Text Available Androctonus crassicauda is the second most frequent causes of scorpion sting in south-west Iran. Its venom can cause sever pain, autonomic, central nervous system (CNS, muscle function disturbances, and death. Appropriate medi­cal and nursing cares can lead to complete recovery with no sequel .The majority of scorpion stings are oligosympto­matic, occurring mainly on the hands and feet (about 90%. Here one rare case of a scorpion sting on the scro­tum is reported from Kashan, central Iran.                                                 

  19. Scrotum Injury by Scorpion Sting

    Directory of Open Access Journals (Sweden)

    R Dehghani

    2008-06-01

    Full Text Available Androctonus crassicauda is the second most frequent causes of scorpion sting in south-west Iran. Its venom can cause sever pain, autonomic, central nervous system (CNS, muscle function disturbances, and death. Appropriate medi­cal and nursing cares can lead to complete recovery with no sequel .The majority of scorpion stings are oligosympto­matic, occurring mainly on the hands and feet (about 90%. Here one rare case of a scorpion sting on the scro­tum is reported from Kashan, central Iran.                                                 

  20. Penis wound by scorpion sting

    Directory of Open Access Journals (Sweden)

    Adriano Scaff Garcia

    1999-03-01

    Full Text Available CONTEXT: The majority of scorpion stings are oligosymptomatic, occurring mainly on the hands and feet. Fatality is rare. CASE REPORT: A 33-year old man suffered a severe sting on his penis from a scorpion of the species Tytius trivittatus. Alcohol and salt were used without success in an effort to relieve pain. Medical assistance was sought 4 hours after the event, at which time diffuse erythema, edema and punctiform injury on the glans penis were observed, with no systemic manifestation. Intravenous meperidine was administered with immediate relief of the pain. The local signs disappeared within 48 hours, with the patient remaining asymptomatic.

  1. Scorpion venoms in gastric cancer

    Science.gov (United States)

    Zhang, Xiao-Ying; Zhang, Pei-Ying

    2016-01-01

    Venom secretions from snakes, scorpions, spiders and bees, have been widely applied in traditional medicine and current biopharmaceutical research. Possession of anticancer potential is another novel discovery for animal venoms and toxins. An increasing number of studies have shown the anticancer effects of venoms and toxins of snakes, and scorpions in vitro and in vivo, which were achieved mainly through the inhibition of cancer growth, arrest of cell cycle, induction of apoptosis and suppression of cancer metastasis. However, more evidence is needed to support this concept and the mechanisms of anticancer actions are not clearly understood. The present review is focused on the recant updates on anticancer venom research. PMID:27900054

  2. Anaphylaxis to scorpion antivenin and its management following envenomation by Indian red scorpion, Mesobuthus tamulus

    OpenAIRE

    Rahul Ramesh Bhoite; Girija Ramesh Bhoite; Dayanand N Bagdure; Himmatrao S Bawaskar

    2015-01-01

    Mesobuthus tamulus is an Indian red scorpion that is responsible for numerous cases of scorpion stings in the Indian subcontinent. Antivenin, vasodilators, and benzodiazepines are medications of choice in the treatment of scorpion bites. Adverse reactions such as anaphylaxis to antivenin have been infrequently described in the literature. We, herein, present a case of a 42-year-old man stung by Indian red scorpion while gardening at home in India, who presented with extreme pain at the sting ...

  3. Genetic mechanisms of scorpion venom peptide diversification.

    Science.gov (United States)

    Zhijian, Cao; Feng, Luo; Yingliang, Wu; Xin, Mao; Wenxin, Li

    2006-03-01

    The diversity of scorpion venom peptides is well shown by the presence of about 400 such polypeptides with or without disulfide bonds. Scorpion toxins with disulfide bonds present a variety of sequence features and pharmacological functions by affecting different ion channels, while the venom peptides without disulfide bonds represent a new subfamily, having much lower sequence homology among each other and different functions (e.g. bradykinin-potentiating, antimicrobial, molecular cell signal initiating and immune modulating). Interestingly, all scorpion venom peptides with divergent functions may have evolved from a common ancestor gene. Over the lengthy evolutionary time, the diversification of scorpion venom peptides evolved through polymorphism, duplication, trans-splicing, or alternative splicing at the gene level. In order to completely clarify the diversity of scorpion toxins and toxin-like peptides, toxinomics (genomics and proteomics of scorpion toxins and toxin-like peptides) are expected to greatly advance in the near future.

  4. A profile of scorpionism, including the species of scorpions involved, in the State of Amazonas, Brazil.

    Science.gov (United States)

    Costa, Cícero Lucinaldo Soares de Oliveira; Fé, Nelson Ferreira; Sampaio, Iracilda; Tadei, Wanderli Pedro

    2016-01-01

    This study investigated scorpionism profile in the State of Amazonas, Brazil. Data referring to stinging incidents were obtained from the National Databank of Major Causes of Morbidity. Information on the scorpion species involved was obtained from the Amazonas State health units. Amazonas has a scorpionism rate of 8.14 cases/100,000 inhabitants. Some municipalities (e.g., Apuí) presented higher rates (273 cases/100,000 inhabitants). Most species involved in envenomation belonged to the genus Tityus. Our results reaffirm the notion of scorpionism being a public health hazard and provide data that can guide public policy aimed at scorpionism prevention and treatment.

  5. Functional unit size of the neurotoxin receptors on the voltage-dependent sodium channel.

    Science.gov (United States)

    Angelides, K J; Nutter, T J; Elmer, L W; Kempner, E S

    1985-03-25

    Radiation inactivation was used in situ to determine the functional unit sizes of the neurotoxin receptors of the voltage-dependent sodium channel from rat brain. Frozen or lyophilized synaptosomes were irradiated with high energy electrons generated by a linear accelerator and assayed for [3H]saxitoxin, 125I-Leiurus quinquestriatus quinquestriatus (alpha-scorpion toxin), 125I-Centruroides suffusus suffusus (beta-scorpion toxin), and batrachotoxinin-A 20 alpha-[3H]benzoate binding activity. The functional unit size of the neurotoxin receptors determined in situ by target analysis are 220,000 for saxitoxin, 263,000 for alpha-scorpion toxin, and 45,000 for beta-scorpion toxin. Analysis of the inactivation curve for batrachotoxinin-A 20 alpha-benzoate binding to the channel yields two target sizes of Mr approximately 287,000 (50%) and approximately 51,000 (50%). The results are independent of the purity of the membrane preparation. Comparison of the radiation inactivation data with the protein composition of the rat brain sodium channel indicates that there are at least two functional components.

  6. Scorpion antivenom effect of micropropagated Aristolochia elegans.

    Science.gov (United States)

    Izquierdo, Alejandro Mora; Zapata, Elsa Ventura; Jiménez-Ferrer, J Enrique; Muñoz, Crescencio Bazaldúa; Aparicio, Antonio Jiménez; Torres, Kalina Bermúdez; Torres, Lidia Osuna

    2010-08-01

    Aristolochia elegans Mast. (Aristolochiaceae) has been used to treat scorpion envenoming in Mexican traditional medicine. In vitro studies of the pharmacological activity of raw extracts from A. elegans roots have shown activity against scorpion bite. The aim of the present study was to determine for the first time the antagonistic effect of hexane and methanol extracts of the aerial parts and roots from micropropagated A. elegans plants in a model of isolated guinea-pig ileum contracted by scorpion bite. Results showed that the methanol extracts of aerial organs (74%) and roots (65%) of micropropagated plants have a similar antitoxin activity against scorpion poisoning to hexane extracts of wild plants (65%). These results suggest that using methanol extracts from the micropropagated plant material instead of wild plant root extracts from A. elegans is an alternative for treatment against scorpion bite symptoms, and will contribute to the conservation of this medicinal species.

  7. Introducing Compsobuthus matthiesseni (Birula, 1905) scorpion as one of the major stinging scorpions in Khuzestan, Iran.

    Science.gov (United States)

    Dehghani, Ruhollah; Djadid, Navid Dinparast; Shahbazzadeh, Dellavar; Bigdelli, Shahlla

    2009-09-01

    Khuzestan province has the highest rate of scorpion sting in Iran. This is a study to identify these scorpions in Khuzestan. In this study 418 scorpions were kept in the ethyl alcohol 70%, each being studied by stereomicroscopy and diagnosis key separately. 120 (28.7%) Androctonus crassicauda, 104 (24.9%) Hemiscorpius lepturus, 91 (21.7%) Mesobuthus eupeus, 86 (20.65%) Compsobuthus matthiesseni, 14 (3.35%) Hottentotta saulcyi, 2 (0.5%) Orthochirus scrobiculosus and 1 (0.25%) Hottentotta schach were identified. H. lepturus is in the Hemiscorpiidae family and the rest are in Buthidae. C. matthiesseni is the most frequent and O. scrobiculosus is the least frequent newly identified scorpion. This study adds two new sting scorpions to the previous list of 8 identified scorpions in Iran.

  8. Overview of Scorpion Species from China and Their Toxins

    Directory of Open Access Journals (Sweden)

    Zhijian Cao

    2014-02-01

    Full Text Available Scorpions are one of the most ancient groups of terrestrial animals. They have maintained a steady morphology over more than 400 million years of evolution. Their venom arsenals for capturing prey and defending against predators may play a critical role in their ancient and conservative appearance. In the current review, we present the scorpion fauna of China: 53 species covering five families and 12 genera. We also systematically list toxins or genes from Chinese scorpion species, involving eight species covering four families. Furthermore, we review the diverse functions of typical toxins from Chinese scorpion species, involving Na+ channel modulators, K+ channel blockers, antimicrobial peptides and protease inhibitors. Using scorpion species and their toxins from China as an example, we build the bridge between scorpion species and their toxins, which helps us to understand the molecular and functional diversity of scorpion venom arsenal, the dynamic and functional evolution of scorpion toxins, and the potential relationships of scorpion species and their toxins.

  9. Overview of scorpion species from China and their toxins.

    Science.gov (United States)

    Cao, Zhijian; Di, Zhiyong; Wu, Yingliang; Li, Wenxin

    2014-02-26

    Scorpions are one of the most ancient groups of terrestrial animals. They have maintained a steady morphology over more than 400 million years of evolution. Their venom arsenals for capturing prey and defending against predators may play a critical role in their ancient and conservative appearance. In the current review, we present the scorpion fauna of China: 53 species covering five families and 12 genera. We also systematically list toxins or genes from Chinese scorpion species, involving eight species covering four families. Furthermore, we review the diverse functions of typical toxins from Chinese scorpion species, involving Na+ channel modulators, K+ channel blockers, antimicrobial peptides and protease inhibitors. Using scorpion species and their toxins from China as an example, we build the bridge between scorpion species and their toxins, which helps us to understand the molecular and functional diversity of scorpion venom arsenal, the dynamic and functional evolution of scorpion toxins, and the potential relationships of scorpion species and their toxins.

  10. Epidemiological Survey of Scorpion Sting Cases and Identification of Scorpion Fauna in Hamadan City, Iran (2013

    Directory of Open Access Journals (Sweden)

    M. Nazari

    2015-10-01

    Full Text Available Introduction & Objective: Iran is among the countries with a variety of scorpion species, particu-larly dangerous ones. Death due to scorpion sting occurs in all parts of the country. Mortality from scorpion sting depends on various factors such as scorpion species, age of the stung per-son, stung body site and geographical area. Considering the fact that so far no research on the fauna and epidemiological aspect of scorpion stings has been done in Hamadan city, we con-ducted this research. Materials & Methods: This is a cross sectional- descriptive study. To determine the scorpion fauna of the region using a random cluster sampling in specified locations from May to Sep-tember in 2013 and was attempting we caught scorpions and put them in containers of alcohol (70% and identified them based on Iran scorpions´ key. In order to investigate cases of scor-pion stings, we referred to the health center of Hamadan province and using questionnaires, we collected data related to the patients during 2010-2013. The data were analyzed by SPSS software. Results: A total of 98 collected scorpion species named Mesobuthus eupeus, Androctonus crassicauda, Odontobuthus doriae and Razianus zarudnyi (Family: Buthidae, were identified. Mesobuthus eupeus species with 89.7% of the samples collected had the highest frequency. Totally, 797 cases of scorpion sting were documented in the Health Center of Hamadan Prov-ince, including 498 (62.5% male and 299 (37.5% females. The results of this study showed that most cases of scorpion stings in the age group of 25 to 34 years, in 2011 in July and in the rural areas were 29.6%, 33.1%, 28.9%, 64.4%, respectively. The most stung organs were hands, with 48.2%. All patients (100% during the study were treated. Conclusion: Due to the low-risk species of scorpions in the region and lack of mortality reports in the past few years, it is recommended to revise administering anti-scorpion serum in the health centers. Adequate

  11. Scorpion toxins prefer salt solutions.

    Science.gov (United States)

    Nikouee, Azadeh; Khabiri, Morteza; Cwiklik, Lukasz

    2015-11-01

    There is a wide variety of ion channel types with various types of blockers, making research in this field very complicated. To reduce this complexity, it is essential to study ion channels and their blockers independently. Scorpion toxins, a major class of blockers, are charged short peptides with high affinities for potassium channels. Their high selectivity and inhibitory properties make them an important pharmacological tool for treating autoimmune or nervous system disorders. Scorpion toxins typically have highly charged surfaces and-like other proteins-an intrinsic ability to bind ions (Friedman J Phys Chem B 115(29):9213-9223, 1996; Baldwin Biophys J 71(4):2056-2063, 1996; Vrbka et al. Proc Natl Acad Sci USA 103(42):15440-15444, 2006a; Vrbka et al. J Phys Chem B 110(13):7036-43, 2006b). Thus, their effects on potassium channels are usually investigated in various ionic solutions. In this work, computer simulations of protein structures were performed to analyze the structural properties of the key residues (i.e., those that are presumably involved in contact with the surfaces of the ion channels) of 12 scorpion toxins. The presence of the two most physiologically abundant cations, Na(+) and K(+), was considered. The results indicated that the ion-binding properties of the toxin residues vary. Overall, all of the investigated toxins had more stable structures in ionic solutions than in water. We found that both the number and length of elements in the secondary structure varied depending on the ionic solution used (i.e., in the presence of NaCl or KCl). This study revealed that the ionic solution should be chosen carefully before performing experiments on these toxins. Similarly, the influence of these ions should be taken into consideration in the design of toxin-based pharmaceuticals.

  12. The scorpion of Vrachanska Planina

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    VICTOR FET

    2016-05-01

    Full Text Available The only species of Scorpiones in Vrachanska Planina Mountains is Euscorpius deltshevi (Euscorpiidae, which was undescribed until the last year. This species is found in the study area from the foot of the mountains up to 1000 m altitude. It is a Balkan endemic species, distributed in the northeastern part of the Balkan Peninsula, which represents a Carpathian faunal element according to its centre of origin with a centre of dispersion in Western Stara Planina Range. According to DNA marker data, Euscorpius deltshevi has been isolated from its sister species, Euscorpius carpathicus from Southwestern Romania, for 3.1 Myr.

  13. The unfulfilled promises of scorpion insectotoxins.

    Science.gov (United States)

    Ortiz, Ernesto; Possani, Lourival D

    2015-01-01

    Since the description and biochemical characterization of the first insect-specific neurotoxins from scorpion venoms, almost all contributions have highlighted their potential application as leads for the development of potent bioinsecticides. Their practical use, however, has been hindered by different factors, some of which are intrinsically related to the toxins and other external determinants. Recent developments in the understanding of the action mechanisms of the scorpion insectotoxins and their bioactive surfaces, coupled with the exploration of novel bioinsecticide delivery systems have renewed the expectations that the scorpion insectotoxins could find their way into commercial applications in agriculture, as part of integrated pest control strategies. Herein, we review the current arsenal of available scorpion neurotoxins with a degree of specificity for insects, the progress made with alternative delivery methods, and the drawbacks that still preclude their practical use.

  14. Notes on the scorpions (Arachnida, Scorpiones from Xizang with the redescription of Scorpiops jendeki Kovařík, 2000 (Scorpiones, Euscorpiidae from Yunnan (China

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    Zhiyong Di

    2013-05-01

    Full Text Available Until now, there are 26 scorpion species of 7 genera of 5 families recorded in Xizang (China. Xizang Autonomous Region (Tibet is the scorpion biodiversity richest area in China (53 scorpion species of 12 genera of 5 families, also the highest altitude habitat of scorpions in the world. We present information of type specimens, an identification key of the scorpion species from Xizang, the distribution, updated feature pictures, and discussion on the disputed species. The redescriptions of Scorpiops jendeki Kovařík, 2000 (Yunnan and S. tibetanus Hirst, 1911 (Xizang, comments and feature figures of species of genus Scorpiops are provided for identification.

  15. Determination of the Median Lethal Dose and Electrophoretic Pattern of Hottentotta saulcyi (Scorpiones, Buthidae Scorpion Venom

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    ErsenAydın Yağmur

    2015-10-01

    Full Text Available Background: In this study, we investigated the lethal potency, electrophoretic protein pattern and in vivo effects of Hottentotta saulcyi scorpion venom in mice.Methods: Scorpions were collected at night, by using a UV lamp from Mardin Province, Turkey. Venom was obtained from mature H. saulcyi scorpions by electrical stimulation of the telson. The lethality of the venom was determined by i.v. injections using Swiss mice. In vivo effects of the venom were assessed by using the intraperitoneal route (ip injections into mice (20±1g and monitored for 24 h. The protein profiles of the scorpion venom were analyzed by NuPAGE® Novex® 4–12 % gradient Bis-Tris gel followed by Coomassie blue staining.Results: The lethal assay of the venom was 0.73 mg/kg in mice. We determined the electrophoretic protein pattern of this scorpion venom to be 4, 6, 9, 31, 35, 40, 46 and 69 kDa by SDS-PAGE. Analysis of electrophoresis indicated that H. saulcyi scorpion intoxicated mice exhibited autonomic nervous system symptoms (tachypnea, restlessness, hyperexcitability, convulsions, salivation, lacrimation, weakness.Conclusions: Hottentotta saulcyi scorpion venom includes short-chain neurotoxins and long-chain neurotoxins according to the electrophoretic protein patterns. The stings of H. saulcyi scorpion must be considered of risk for humans in the southeastern region, Turkey.

  16. Scorpion envenomation symptoms in pregnant women

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    H. Ben Nasr

    2007-01-01

    Full Text Available Scorpion envenomation is common in many countries; however, its effects on pregnancy are still unclear. In the present paper, we described the effects of scorpion envenomation on pregnant patients. A retrospective study was carried out considering the clinical and laboratory exams of patients admitted to the emergency room of Habib Bourguiba Hospital, Sfax, Tunisia, from 1990 to 2004. Variability of these clinical and laboratory profiles according to maternal age, gestational age and number of previous parities was also discussed. Among 167 scorpion-envenomed women, age ranged from 17 to 42 years, 7.18% were pregnant. These presented symptoms similar to those of non-pregnant women envenomed by scorpions. Two pregnant patients developed intense pelvic pain and one manifested vaginal bleeding. Although the studied parameters showed non-significant differences, we could conclude that scorpion envenomation may lead to abnormal uterine contraction probably causing preterm delivery. Maternal disturbances induced by scorpion envenomation may influence the fetus development. The effects were more severe in the second trimester of pregnancy.

  17. Sustained Ventricular Tachycardia and Cardiogenic Shock due to Scorpion Envenomation

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    Carlos Henrique Miranda

    2014-01-01

    Full Text Available We describe a case of severe scorpion envenomation in an adult patient, with the presence of very rapid sustained ventricular tachycardia followed by cardiogenic shock, which was reversed by scorpion antivenom administration. Scorpion venom causes cardiac changes that can lead to an environment favoring arrhythmogenesis.

  18. Optical properties of a scorpion (Centruroides limpidus)

    Science.gov (United States)

    Ullrich, Bruno; Duckworth, Robyn M.; Singh, Akhilesh K.; Barik, Puspendu; Mejía-Villanueva, Vicente O.; Garcia-Pérez, Alberto C.

    2016-04-01

    Scorpions, elusive by nature, tend to appear nocturnally and are usually not appreciated when encountered. The exoskeleton is capable of fluorescing allowing for their detection at night in order to prevent undesirable encounters. The specificity of their fluorescing suggests specialized optical features. However, despite the blue-green fluorescence, to the best of our knowledge, no further results have been published on the optical properties of scorpions. Their exoskeletal structure whose versatility provides them protection, camouflage, and flexibility has not been studied under laser excitation and monochromatic light. The experiments reveal the nonlinear optical properties, infrared photoluminescence, and photoconductivity of the epicuticle of scorpions, demonstrating that the scorpion’s outer-covering is a prototype of a semiconducting inherently integrated multifunctional polymeric film with appealing potential applications such as optical logics, photonic frequency converters, novel multiplexers handling electronic and photonic inputs, and lasers.

  19. Evidence for the existence of a common ancestor of scorpion toxins affecting ion channels.

    Science.gov (United States)

    Zhijian, Cao; Yingliang, Wu; Jiqun, Sheng; Wanhong, Liu; Fan, Xiao; Xin, Mao; Hui, Liu; Dahe, Jiang; Wenxin, Li

    2003-01-01

    All scorpion toxins from different 30 species are simply reviewed. A new classification system of scorpion toxins is first proposed: scorpion toxins are classified into three families (long-chain scorpion toxins with 4 disulfide bridges, short-chain scorpion toxins with 3 disulfide bridges, and intermediate-type scorpion toxins with 3 or 4 disulfide bridges). Intermediate-type scorpion toxins provide a strong proof for the conclusion that channel toxins from scorpion venoms evolve from a common ancestor. Common organization of precursor nucleotides and genomic sequence, similar 3-dimensional structure, and the existence of intermediate type scorpion toxins and functionally intercrossing scorpion toxins show that all scorpion toxins affecting ion channels evolve from the common ancestor, which produce millions of scorpion toxins with function-diversity. Copyright 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:235-238, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10083

  20. [Scorpion envenomation in Morocco: scorpions of the genus Androctonus, Buthus and Hottentota].

    Science.gov (United States)

    Aboumaâd, B; Iba, N; Dersi, N

    2014-02-01

    Around the world and especially in summer, the scorpion envenomation is a real public health problem. In Morocco, its gravity is due to the diversity of genera of the Buthidae family whose their venom is potentially lethal, mainly the genus Androctonus, Buthus and Hottentota. The areas most affected by this problematic are the central and southern of Morocco. The lethality of scorpion's venom primarily affects children. It is rich in neurotoxic polypeptides that have targeted ion channel membrane Na(+), K(+) activated or not by Ca(++). The toxins polymorphism causes pathophysiological disorders. The diversity of symptomatic treatment in the absence of immunotherapy is due to variability in clinical pictures, which depends on the species involved and the patient at risk. The objective of this review is to highlight the magnitude of the scorpion envenomation by describing its epidemiological characteristics, elucidate the pathophysiological effects of the venom of the most dangerous scorpions in Morocco the genus Androctonus, Buthus and Hottentota, and their therapeutic treatment.

  1. Assessing and managing spider and scorpion envenomation.

    Science.gov (United States)

    McGhee, Stephen; Weiner, Aaron; Finnegan, Alan; Visovsky, Constance; Clochesy, John M; Graves, Brian

    2015-11-01

    Envenomation by spiders or scorpions is a public health problem in many parts of the world and is not isolated to the tropics and subtropics. Spiders and scorpions can be unintentionally transported globally, and keeping them as pets is becoming more popular, so envenomation can occur anywhere. Emergency nurses should be prepared to assess and treat patients who present with a bite or sting. This article gives an overview of the signs, symptoms and treatment of envenomation by species of arachnids that are clinically significant to humans.

  2. The scorpions of Yunnan (China: updated identification key, new record, and distributions (Arachnida: Scorpiones

    Directory of Open Access Journals (Sweden)

    Zhiyong Di

    2011-02-01

    Full Text Available This is an identification key to the Scorpiones species of Yunnan (China with notes on the distribution and habitats of these species. E. kubani is one new record species to China. The number of known species of Scorpiones from Yunnan is raised to nine. The redescriptions of E. shidian and E. kubani are provided. Features and distribution of these species provided as additional information for identification.

  3. Activity trends and movement distances in the Arizona bark scorpion (Scorpiones: Buthidae).

    Science.gov (United States)

    Bibbs, Christopher Stephen; Bengston, Sarah Elizabeth; Gouge, Dawn Heather

    2014-12-01

    The bark scorpion, Centruroides sculpturatus Ewing, is a nocturnal, cryptic, nonburrowing, mobile species that is common in urban landscapes spanning the desert southwest. Bark scorpions are often found in dense localized populations in cities, but the question of whether this is because the species is metabolically movement limited or choose to aggregate has not been addressed. Field observations lead us to believe that the scorpions move very little. Their ability to move is tested here. A circular pacing ring was constructed to observe the distance individuals could move in 2 h under both dark and light conditions. Observations under light motivate the arthropods to move, and significantly greater distances were observed in light trials, the maximum travel distance being 104.37 m, while the maximum distance in dark trials was 14.63 m. To monitor movement in the field, telemetry tags were used to mark female and male scorpions over 21 d during which relocation distances were recorded daily. Additionally, 12-h and 6-h overnight observational periods took place during which, scorpion movements were recorded hourly. Overall, it was found that scorpions moved significantly more in the pacing ring than in the field, indicating that field individuals are not moving at their maximum potential. Movement limitation does not explain their distribution pattern. In both the pacing ring and field, gender and pregnancy status had significant influence on distances moved. We conclude that C. sculpturatus is capable of much greater movement than is typically observed in the field.

  4. Extract from Buthus martensii Karsch is associated with potassium channels on glioma cells

    Institute of Scientific and Technical Information of China (English)

    Mingxian Li; Hongmei Meng; Shao Wang; Min Huang; Li Cui; Weihong Lin

    2011-01-01

    Catilan extracted from Leiurus quinquestriatus is a specific ion channel blocker.It can specifically bind chloride channels of glioma cells and kill these tumor cells.The questions remain as to whether antigliomatin,the extract from scorpion venom of Buthus martensii Karsch in China,can inhibit glioma growth,and whether this inhibition is correlated with ion channels of tumor cells.The present study treated rat C6 glioma cells with 0.8,1.2,and 1.6 μg/mL antigliomatin for 20 hours.Whole-cell patch clamp technique showed that antigliomatin delayed rectifier potassium channels of C6 glioma cells.Antigliomatin inhibited tumor growth,which could potentially involve potassium channels of tumor cells.

  5. Mucormycosis after scorpion sting: case report.

    Science.gov (United States)

    Pourahmad, Morteza; Sepidkar, Abdolali; Farokhnia, Mohmmad H; Tadayon, Seyed M K; Salehi, Hassan; Zabetian, Hassan

    2013-09-01

    Mucor is a fungus, which give rise to opportunistic infection in immunocompromised patients. We described a 55-year-old immunocompetent woman with cutaneous mucormycosis after scorpion sting. Mucormycosis may happen in patients with intact immunity and is not allocated only to patients with immune deficiency.

  6. Target-Driven Evolution of Scorpion Toxins.

    Science.gov (United States)

    Zhang, Shangfei; Gao, Bin; Zhu, Shunyi

    2015-10-07

    It is long known that peptide neurotoxins derived from a diversity of venomous animals evolve by positive selection following gene duplication, yet a force that drives their adaptive evolution remains a mystery. By using maximum-likelihood models of codon substitution, we analyzed molecular adaptation in scorpion sodium channel toxins from a specific species and found ten positively selected sites, six of which are located at the core-domain of scorpion α-toxins, a region known to interact with two adjacent loops in the voltage-sensor domain (DIV) of sodium channels, as validated by our newly constructed computational model of toxin-channel complex. Despite the lack of positive selection signals in these two loops, they accumulated extensive sequence variations by relaxed purifying selection in prey and predators of scorpions. The evolutionary variability in the toxin-bound regions of sodium channels indicates that accelerated substitutions in the multigene family of scorpion toxins is a consequence of dealing with the target diversity. This work presents an example of atypical co-evolution between animal toxins and their molecular targets, in which toxins suffered from more prominent selective pressure from the channels of their competitors. Our discovery helps explain the evolutionary rationality of gene duplication of toxins in a specific venomous species.

  7. Identification and determination of Lorestan scorpions funa

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    mahmood reza Taherian

    2004-01-01

    Conclusion: Results shows that most of the scorpions belonged to the Buthidae family and Buthuthus Snulcyi kind which have painful stings which affect on nervous system , and are very dangerous and fatal for children and aged people , so it is important to know the treatment methods to fight against their poisons.

  8. Pulmonary Edema and Myocarditis Developing Due to Scorpion Stings

    Directory of Open Access Journals (Sweden)

    Sevdegul Karadas

    2015-11-01

    Full Text Available Although most of the scorpion stings are harmless, deadly species of scorpions may cause multiorgan failure, neurotoxicity, cardiotoxicity, and pulmonary edema. The cases should be observed in the emergency department against the possibility of development of systemic effects. Fatal complications, in particular such as pulmonary edema, and myocarditis should be considered. In this study, a case of myocarditis and pulmonary edema was detected on the patient who had applied to the emergency department due to a scorpion sting is presented.

  9. Overview of Scorpion Species from China and Their Toxins

    OpenAIRE

    Zhijian Cao; Zhiyong Di; Yingliang Wu; Wenxin Li

    2014-01-01

    Scorpions are one of the most ancient groups of terrestrial animals. They have maintained a steady morphology over more than 400 million years of evolution. Their venom arsenals for capturing prey and defending against predators may play a critical role in their ancient and conservative appearance. In the current review, we present the scorpion fauna of China: 53 species covering five families and 12 genera. We also systematically list toxins or genes from Chinese scorpion species, involving ...

  10. Scorpion envenomation study in Behbahan County, Southwest Iran

    Institute of Scientific and Technical Information of China (English)

    Hamid Kassiri; Ali Kassiri; Mona Sharififard; Samaneh Shojaee; Masoud Lotfi; Elnaz Kasiri

    2014-01-01

    Objective:To study the incidence and epidemiology of scorpion sting cases that were referred to the health services centers of Behbahan County, Khuzistan Province, southwestern Iran, during the two yeare (2007-2008). Methods: In this descriptive retrospective research, the data has come from files of scorpion-stung patients referring to the health services centers of Behbahan during study period. A special scorpion sting sheet was prepared and completed for every case of scorpion sting. Analysis of 3441 case sheets received during this period was carried out. The frequencies of medical and entomo-epidemiologic parameters were turned to the percentage position. Results:A total of 3 441 cases of scorpion stings were reported during the two-year period from 2007 to 2008. The average incidence of scorpion stings was 8.8‰in the two years. The frequency of cases was higher during August, September, June and July that 2 056 cases of scorpion stings were reported. Most stings were occurred during summer. Nearly 51.3%of the cases were men. All cases had received antivenin. Majority of scorpion sting cases (56.5%) lived in the rural areas. The most common sting site was the hand. About 74.4%have received the antivenin 0-6 h after the sting. The early injection of the antivenin is very important. The most of the cases of scorpion stings (59%) were occurred by yellow scorpions. Conclusions: Surveillance for cases of scorpion stings must begin at all regions of Behbahan County. Treatment of cases of scorpion stings is conducted according to a protocol set by the Ministry of Health, Treatment and Medical Education. This protocol included directions for lines of treatment and the dose of antivenin recommended. Thereafter all cases are referred to hospital for further observation and management.

  11. Scorpions from Mexico: From Species Diversity to Venom Complexity.

    Science.gov (United States)

    Santibáñez-López, Carlos E; Francke, Oscar F; Ureta, Carolina; Possani, Lourival D

    2015-12-24

    Scorpions are among the oldest terrestrial arthropods, which are distributed worldwide, except for Antarctica and some Pacific islands. Scorpion envenomation represents a public health problem in several parts of the world. Mexico harbors the highest diversity of scorpions in the world, including some of the world's medically important scorpion species. The systematics and diversity of Mexican scorpion fauna has not been revised in the past decade; and due to recent and exhaustive collection efforts as part of different ongoing major revisionary systematic projects, our understanding of this diversity has changed compared with previous assessments. Given the presence of several medically important scorpion species, the study of their venom in the country is also important. In the present contribution, the diversity of scorpion species in Mexico is revised and updated based on several new systematic contributions; 281 different species are recorded. Commentaries on recent venomic, ecological and behavioral studies of Mexican scorpions are also provided. A list containing the most important peptides identified from 16 different species is included. A graphical representation of the different types of components found in these venoms is also revised. A map with hotspots showing the current knowledge on scorpion distribution and areas explored in Mexico is also provided.

  12. Scorpion envenomation study in Behbahan County, Southwest Iran

    Directory of Open Access Journals (Sweden)

    Hamid Kassiri

    2014-05-01

    Full Text Available Objective: To study the incidence and epidemiology of scorpion sting cases that were referred to the health services centers of Behbahan County, Khuzistan Province, southwestern Iran, during the two yeare (2007-2008. Methods: In this descriptive retrospective research, the data has come from files of scorpionstung patients referring to the health services centers of Behbahan during study period. A special scorpion sting sheet was prepared and completed for every case of scorpion sting. Analysis of 3441 case sheets received during this period was carried out. The frequencies of medical and entomoepidemiologic parameters were turned to the percentage position. Results: A total of 3 441 cases of scorpion stings were reported during the two-year period from 2007 to 2008. The average incidence of scorpion stings was 8.8‰ in the two years. The frequency of cases was higher during August, September, June and July that 2 056 cases of scorpion stings were reported. Most stings were occurred during summer. Nearly 51.3% of the cases were men. All cases had received antivenin. Majority of scorpion sting cases (56.5% lived in the rural areas. The most common sting site was the hand. About 74.4% have received the antivenin 0-6 h after the sting. The early injection of the antivenin is very important. The most of the cases of scorpion stings (59% were occurred by yellow scorpions. Conclusions: Surveillance for cases of scorpion stings must begin at all regions of Behbahan County. Treatment of cases of scorpion stings is conducted according to a protocol set by the Ministry of Health, Treatment and Medical Education. This protocol included directions for lines of treatment and the dose of antivenin recommended. Thereafter all cases are referred to hospital for further observation and management.

  13. Scorpion: Close Air Support (CAS) aircraft

    Science.gov (United States)

    Allen, Chris; Cheng, Rendy; Koehler, Grant; Lyon, Sean; Paguio, Cecilia

    1991-01-01

    The objective is to outline the results of the preliminary design of the Scorpion, a proposed close air support aircraft. The results obtained include complete preliminary analysis of the aircraft in the areas of aerodynamics, structures, avionics and electronics, stability and control, weight and balance, propulsion systems, and costs. A conventional wing, twin jet, twin-tail aircraft was chosen to maximize the desirable characteristics. The Scorpion will feature low speed maneuverability, high survivability, low cost, and low maintenance. The life cycle cost per aircraft will be 17.5 million dollars. The maximum takeoff weight will be 52,760 pounds. Wing loading will be 90 psf. The thrust to weight will be 0.6 lbs/lb. This aircraft meets the specified mission requirements. Some modifications have been suggested to further optimize the design.

  14. Transcriptome analysis of the venom gland of the Mexican scorpion Hadrurus gertschi (Arachnida: Scorpiones

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    Rodríguez de la Vega Ricardo C

    2007-05-01

    Full Text Available Abstract Background Scorpions like other venomous animals posses a highly specialized organ that produces, secretes and disposes the venom components. In these animals, the last postabdominal segment, named telson, contains a pair of venomous glands connected to the stinger. The isolation of numerous scorpion toxins, along with cDNA-based gene cloning and, more recently, proteomic analyses have provided us with a large collection of venom components sequences. However, all of them are secreted, or at least are predicted to be secretable gene products. Therefore very little is known about the cellular processes that normally take place inside the glands for production of the venom mixture. To gain insights into the scorpion venom gland biology, we have decided to perform a transcriptomic analysis by constructing a cDNA library and conducting a random sequencing screening of the transcripts. Results From the cDNA library prepared from a single venom gland of the scorpion Hadrurus gertschi, 160 expressed sequence tags (ESTs were analyzed. These transcripts were further clustered into 68 unique sequences (20 contigs and 48 singlets, with an average length of 919 bp. Half of the ESTs can be confidentially assigned as homologues of annotated gene products. Annotation of these ESTs, with the aid of Gene Ontology terms and homology to eukaryotic orthologous groups, reveals some cellular processes important for venom gland function; including high protein synthesis, tuned posttranslational processing and trafficking. Nonetheless, the main group of the identified gene products includes ESTs similar to known scorpion toxins or other previously characterized scorpion venom components, which account for nearly 60% of the identified proteins. Conclusion To the best of our knowledge this report contains the first transcriptome analysis of genes transcribed by the venomous gland of a scorpion. The data were obtained for the species Hadrurus gertschi, belonging

  15. Analysis of scorpion venom composition by Raman Spectroscopy

    Science.gov (United States)

    Martínez-Zérega, Brenda E.; González-Solís, José L.

    2015-01-01

    In this work we study the venom of two Centruroides scorpion species using Raman spectroscopy. The spectra analysis allows to determine the venoms chemical composition and to establish the main differences and similarities among the species. It is also shown that the use of Principal Component Analysis may help to tell apart between the scorpion species.

  16. The Lesser Antillean scorpions of the genus Centruroides

    NARCIS (Netherlands)

    Armas, de Luis F.

    1983-01-01

    The buthid scorpions of the genus Centruroides are widely distributed in the Antillean area. They are also the most common scorpions in the majority of these islands. Nevertheless they remained almost forgotten until recently (STAHNKE 1970; ARMAS 1976, 1977, 1980, 1981, 1982; FRANCKE & SISSOM 1980).

  17. [Epidemiological data on scorpion envenomation in Algeria].

    Science.gov (United States)

    Hellal, H; Guerinik, M; Griene, L; Laid, Y; Mesbah, S; Merad, R; Alamir, B

    2012-08-01

    The scorpion envenomation is a major public health problem in Algeria. Given this fact, the Ministry of Health has developed a national strategy for prevention and control based on the training of health personnel, information, education and communication, and standardization of care on the basis of a therapeutic consensus. The monitoring and evaluation activities are carried out by epidemiological indicators through the implementation of an information system based in the services of Epidemiology, INSP (National Institute of Public Health) and Prevention Department of the Health Ministry. The information carriers are report cards implemented in different health facilities that collect data on bites and deaths from scorpion envenomation. Summaries of notifications from the wilayas are collected monthly, and processed by the Epi info software using monitoring indicators. From 1991 to 2010, there has been a stagnation in the number of stings with an average of 50,000 cases per year, but mortality decreased from more than 100 deaths in the last fifty years to 50 nowadays. The higher proportion of stings was recorded during the summer period. The most affected group is from 15 to 49 years which constitute the workforce, but children from 5 to 14 years rank first in terms of mortality. But these rates vary across years and regions. Despite all these efforts, the scorpion envenomation in Algeria remains of concern and our main challenges are to strengthen cross-sectional actions at the local level and improving the quality of care.

  18. Biotechnological Trends in Spider and Scorpion Antivenom Development

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard; Solà, Mireia; Jappe, Emma Christine

    2016-01-01

    Spiders and scorpions are notorious for their fearful dispositions and their ability to inject venom into prey and predators, causing symptoms such as necrosis, paralysis, and excruciating pain. Information on venom composition and the toxins present in these species is growing due to an interest...... in using bioactive toxins from spiders and scorpions for drug discovery purposes and for solving crystal structures of membrane-embedded receptors. Additionally, the identification and isolation of a myriad of spider and scorpion toxins has allowed research within next generation antivenoms to progress...... at an increasingly faster pace. In this review, the current knowledge of spider and scorpion venoms is presented, followed by a discussion of all published biotechnological efforts within development of spider and scorpion antitoxins based on small molecules, antibodies and fragments thereof, and next generation...

  19. Transcriptome analysis of the venom gland of the scorpion Scorpiops jendeki: implication for the evolution of the scorpion venom arsenal

    Directory of Open Access Journals (Sweden)

    Wu Yingliang

    2009-07-01

    Full Text Available Abstract Background The family Euscorpiidae, which covers Europe, Asia, Africa, and America, is one of the most widely distributed scorpion groups. However, no studies have been conducted on the venom of a Euscorpiidae species yet. In this work, we performed a transcriptomic approach for characterizing the venom components from a Euscorpiidae scorpion, Scorpiops jendeki. Results There are ten known types of venom peptides and proteins obtained from Scorpiops jendeki. Great diversity is observed in primary sequences of most highly expressed types. The most highly expressed types are cytolytic peptides and serine proteases. Neurotoxins specific for sodium channels, which are major groups of venom components from Buthidae scorpions, are not detected in this study. In addition to those known types of venom peptides and proteins, we also obtain nine atypical types of venom molecules which haven't been observed in any other scorpion species studied to date. Conclusion This work provides the first set of cDNAs from Scorpiops jendeki, and one of the few transcriptomic analyses from a scorpion. This allows the characterization of a large number of venom molecules, belonging to either known or atypical types of scorpion venom peptides and proteins. Besides, our work could provide some clues to the evolution of the scorpion venom arsenal by comparison with venom data from other scorpion lineages.

  20. Transcriptome analysis of the venom gland of the scorpion Scorpiops jendeki: implication for the evolution of the scorpion venom arsenal

    Science.gov (United States)

    Ma, Yibao; Zhao, Ruiming; He, Yawen; Li, Songryong; Liu, Jun; Wu, Yingliang; Cao, Zhijian; Li, Wenxin

    2009-01-01

    Background The family Euscorpiidae, which covers Europe, Asia, Africa, and America, is one of the most widely distributed scorpion groups. However, no studies have been conducted on the venom of a Euscorpiidae species yet. In this work, we performed a transcriptomic approach for characterizing the venom components from a Euscorpiidae scorpion, Scorpiops jendeki. Results There are ten known types of venom peptides and proteins obtained from Scorpiops jendeki. Great diversity is observed in primary sequences of most highly expressed types. The most highly expressed types are cytolytic peptides and serine proteases. Neurotoxins specific for sodium channels, which are major groups of venom components from Buthidae scorpions, are not detected in this study. In addition to those known types of venom peptides and proteins, we also obtain nine atypical types of venom molecules which haven't been observed in any other scorpion species studied to date. Conclusion This work provides the first set of cDNAs from Scorpiops jendeki, and one of the few transcriptomic analyses from a scorpion. This allows the characterization of a large number of venom molecules, belonging to either known or atypical types of scorpion venom peptides and proteins. Besides, our work could provide some clues to the evolution of the scorpion venom arsenal by comparison with venom data from other scorpion lineages. PMID:19570192

  1. Scorpion sheds 'tail' to escape: consequences and implications of autotomy in scorpions (Buthidae: Ananteris).

    Science.gov (United States)

    Mattoni, Camilo I; García-Hernández, Solimary; Botero-Trujillo, Ricardo; Ochoa, José A; Ojanguren-Affilastro, Andrés A; Pinto-da-Rocha, Ricardo; Prendini, Lorenzo

    2015-01-01

    Autotomy, the voluntary shedding or detachment of a body part at a determined cleavage plane, is a common anti-predation defense mechanism in several animal taxa, including arthropods. Among arachnids, autotomy has been observed in harvestmen, mites, and spiders, always involving the loss of legs. Autotomy of the opisthosoma (abdomen) was recently reported in a single species of the Neotropical buthid scorpion genus Ananteris Thorell, 1891, but few details were revealed. Based on observations in the field and laboratory, examination of material in museum collections, and scanning electron microscopy, we document autotomy of the metasoma (the hind part of the opisthosoma, or 'tail') in fourteen species of Ananteris. Autotomy is more common in males than females, and has not been observed in juveniles. When the scorpion is held by the metasoma, it is voluntarily severed at the joints between metasomal segments I and II, II and III, or III and IV, allowing the scorpion to escape. After detachment, the severed metasoma moves (twitches) automatically, much like the severed tail of a lizard or the severed leg of a spider, and reacts to contact, even attempting to sting. The severed surface heals rapidly, scar tissue forming in five days. The lost metasomal segments and telson cannot be regenerated. Autotomy of the metasoma and telson results in permanent loss of the posterior part of the scorpion's digestive system (the anus is situated posteriorly on metasomal segment V) and the ability to inject venom by stinging. After autotomy, scorpions do not defecate and can only capture small prey items. However, males can survive and mate successfully for up to eight months in the laboratory. In spite of diminished predation ability after autotomy, survival allows males to reproduce. Autotomy in Ananteris therefore appears to be an effective, adaptive, anti-predation escape mechanism.

  2. Scorpion sheds 'tail' to escape: consequences and implications of autotomy in scorpions (Buthidae: Ananteris.

    Directory of Open Access Journals (Sweden)

    Camilo I Mattoni

    Full Text Available Autotomy, the voluntary shedding or detachment of a body part at a determined cleavage plane, is a common anti-predation defense mechanism in several animal taxa, including arthropods. Among arachnids, autotomy has been observed in harvestmen, mites, and spiders, always involving the loss of legs. Autotomy of the opisthosoma (abdomen was recently reported in a single species of the Neotropical buthid scorpion genus Ananteris Thorell, 1891, but few details were revealed. Based on observations in the field and laboratory, examination of material in museum collections, and scanning electron microscopy, we document autotomy of the metasoma (the hind part of the opisthosoma, or 'tail' in fourteen species of Ananteris. Autotomy is more common in males than females, and has not been observed in juveniles. When the scorpion is held by the metasoma, it is voluntarily severed at the joints between metasomal segments I and II, II and III, or III and IV, allowing the scorpion to escape. After detachment, the severed metasoma moves (twitches automatically, much like the severed tail of a lizard or the severed leg of a spider, and reacts to contact, even attempting to sting. The severed surface heals rapidly, scar tissue forming in five days. The lost metasomal segments and telson cannot be regenerated. Autotomy of the metasoma and telson results in permanent loss of the posterior part of the scorpion's digestive system (the anus is situated posteriorly on metasomal segment V and the ability to inject venom by stinging. After autotomy, scorpions do not defecate and can only capture small prey items. However, males can survive and mate successfully for up to eight months in the laboratory. In spite of diminished predation ability after autotomy, survival allows males to reproduce. Autotomy in Ananteris therefore appears to be an effective, adaptive, anti-predation escape mechanism.

  3. Epidemiology of Scorpionism in Iran during 2009

    Directory of Open Access Journals (Sweden)

    Sina Rafizadeh

    2013-03-01

    Full Text Available Background: Scorpion sting is a major health problem in Iran. The aim of current study was to measure the inci­dence rates of scorpion stings, mortality, recovery, and affected age groups. The results of treatment with and with­out anti venom also were considered in the entire country during 2009.Methods: All the data were collected from emergency section of different hospitals and then were analyzed by re­lated software. The responsibility of such data collection and surveillance is related to the Department of Violence and Injury, Ministry of Health and Medical Education of Iran.Results: A total incidence of 59.5/100000 was found for the 12-month period. During the study period the most and the least cases were reported from Khuzestan and Mazandaran provinces with incidence of 541 and 0 per 100000 respectively. Totally 40220 anti venom vials were used, i.e., the ratio of 91 vial/ 100 affected cases. The stings occur mainly in rural areas (57.7%. Young people with the age group of 15–24 years old were the most victims of stings. The mortality and recovery rates of cases who had received anti venom less than 6 h of stings were calculated as 0.01% and 99.9% respectively.Conclusion: The high incidence of scorpion stings in Iran especially in Khuzestan suggests the necessity of preven­tive programmes for decreasing the incidence. Such programmes could start by community educating in the high prevalent areas. In addition prompt and local treatment is particularly important for infants and pre-school children.

  4. Biotechnological Trends in Spider and Scorpion Antivenom Development

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard; Solà, Mireia; Jappe, Emma Christine;

    2016-01-01

    Spiders and scorpions are notorious for their fearful dispositions and their ability to inject venom into prey and predators, causing symptoms such as necrosis, paralysis, and excruciating pain. Information on venom composition and the toxins present in these species is growing due to an interest...... at an increasingly faster pace. In this review, the current knowledge of spider and scorpion venoms is presented, followed by a discussion of all published biotechnological efforts within development of spider and scorpion antitoxins based on small molecules, antibodies and fragments thereof, and next generation...

  5. Brain infarcts due to scorpion stings in children: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Bouzas, A.; Ballesteros-Maresma, A. [Univ. Nacional Autonoma de Mexico, Mexico (Mexico); Morales-Resendiz, M.L. [Hospital General de Queretaro, Mexico (Mexico); Llamas-Ibarra, F. [Clinica Neurologica de Queretaro, Mexico (Mexico); Martinez-Lopez, M. [Fundacion Clinica Medica Sur., Mexico (Mexico)

    2000-02-01

    We report two children with severe neurological complications after having been stung by a scorpion. Clinical and MRI findings suggested brain infarcts. The lesions seen were in pons in one child and the right hemisphere in the other. The latter also showed possible hyperemia in the infarcted area. No vascular occlusions were observed and we therefore think the brain infarcts were a consequence of the scorpion sting. The cause of the infarct may be hypotension, shock or depressed left ventricular function, all of which are frequent in severe poisoning by scorpion sting. (orig.)

  6. Reviewing the structure and function of the scorpion's hepatopancreas

    Directory of Open Access Journals (Sweden)

    M.R. Warburg

    2012-09-01

    Full Text Available During a long-terms study of scorpions, it was possible to follow changes taking place in the mass, water and lipid content of the hepatopancreas in freshly caught Scorpio maurus fuscus. Cyclic events in the female's reproductive state were shown to be affected by the hepatopancreas. There was a high variability among scorpions in the concentrations of metals in the hepatopancreas. The significance of the hepatopancreas in the scorpion, as a multifunctional organ for both storage and filtering constituents, is reviewed and discussed, and various future avenues of research are outlined.

  7. Motor aphasia: A rare complication of scorpion sting

    Directory of Open Access Journals (Sweden)

    Vinayak Y Kshirsagar

    2012-01-01

    Full Text Available Scorpion sting is common in villages, and is an important public health problem in India. The clinical symptoms of envenomation by scorpion sting are by sympathetic and parasympathetic stimulation, causing a variety of symptoms. The leading causes of death are cardiac dysfunction and pulmonary edema. We present herein a case of scorpion sting in a 9-year-old boy who developed pulmonary edema and gradually developed cytotoxic cerebral edema with infarct leading to motor aphasia with upper motor neuron facial palsy.

  8. A simple protocol for venom peptide barcoding in scorpions

    Directory of Open Access Journals (Sweden)

    Stephan Schaffrath

    2014-06-01

    Full Text Available Scorpion venoms contain many species-specific peptides which target ion channels in cell membranes. Without harming the scorpions, these peptides can easily be extracted and detected by MALDI-TOF mass spectrometry. So far, only few studies compared the venom of different species solely for taxonomic purposes. Here, we describe a very simple protocol for venom extraction and mass fingerprinting that was developed for peptide barcoding (venom code for species identification and facilitates reproducibility if sample preparation is performed under field conditions. This approach may serve as suitable basis for a taxonomy-oriented scorpion toxin database that interacts with MALDI-TOF mass spectra.

  9. Study on Distribution of Scorpions to Provide Prevention and Interventions in Combating Scorpionism in Poldokhtar County, Lorestan Province, Iran

    Science.gov (United States)

    Hassan, Rastgar

    2016-01-01

    Introduction Scorpions are arthropods of medical importance classified in the class Arachnida, inhabiting hot and dry environments. All scorpions have a venomous sting and several thousand people die each year from scorpion stings, but this mortality is due to the venom of about 25 species located in northern Africa, the Middle East, India, Mexico and parts of South America. Poldokhtar County belongs to one of the southern cities of Lorestan Province, providing suitable habitats for many different species of scorpions due to its specific climatic conditions. Aim To examine the fauna of scorpion and its distribution in the Poldokhtar County and to provide appropriate preventive and medical interventions in combating scorpionism. Materials and Methods This present study was a descriptive and analytical cross-sectional study. This study was conducted from April 2014 to November 2014 in regions of Poldokhtar County, Lorestan Province, and west of Iran. Cluster sampling methodology was employed in the sampling and scorpion collection procedure. Sampling was undertaken for an eight-month period, in villages and districts, namely, Myankuhe sharqi, Jayedar, Jelogir and Malavi within the county. The Chi-square test and the Fisher-exact test for homogeneity of proportions were used to compare quantitative variables. Results Totally, 393 specimens were captured entailing 193 (49.1%) males and 200 (50.9%) females. There were at least seven species of scorpions belonging to three families; BU= Buthidae, HE = Hemiscorpiidae, SCN = Scorpionidae in Poldokhtar. Out of 393 collected scorpions, seven species, Androctonus crassicauda, Hottentotta (Buthotus) saulcyi, Compsobuthus matthiesseni, Compsobuthus rugosulus, Orthochirus scrobiculosus, Scorpio maurus and Hemiscorpius lepturus were identified. The overall sex ratio of females to males was 1:1.03. Conclusion It is crucial to improve the knowledge of residents in this region regarding preventive methods towards scorpion stinging

  10. Evidence of duplicated Hox genes in the most recent common ancestor of extant scorpions.

    Science.gov (United States)

    Sharma, Prashant P; Santiago, Marc A; González-Santillán, Edmundo; Monod, Lionel; Wheeler, Ward C

    2015-01-01

    Scorpions (order Scorpiones) are unusual among arthropods, both for the extreme heteronomy of their bauplan and for the high gene family turnover exhibited in their genomes. These phenomena appear to be correlated, as two scorpion species have been shown to possess nearly twice the number of Hox genes present in most arthropods. Segmentally offset anterior expression boundaries of a subset of Hox paralogs have been shown to correspond to transitions in segmental identities in the scorpion posterior tagmata, suggesting that posterior heteronomy in scorpions may have been achieved by neofunctionalization of Hox paralogs. However, both the first scorpion genome sequenced and the developmental genetic data are based on exemplars of Buthidae, one of 19 families of scorpions. It is therefore not known whether Hox paralogy is limited to Buthidae or widespread among scorpions. We surveyed 24 high throughput transcriptomes and the single whole genome available for scorpions, in order to test the prediction that Hox gene duplications are common to the order. We used gene tree parsimony to infer whether the paralogy was consistent with a duplication event in the scorpion common ancestor. Here we show that duplicated Hox genes in non-buthid scorpions occur in six of the ten Hox classes. Gene tree topologies and parsimony-based reconciliation of the gene trees are consistent with a duplication event in the most recent common ancestor of scorpions. These results suggest that a Hox paralogy, and by extension the model of posterior patterning established in a buthid, can be extended to non-Buthidae scorpions.

  11. Scorpion Venom and the Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Vera L. Petricevich

    2010-01-01

    Full Text Available Scorpion venoms consist of a complex of several toxins that exhibit a wide range of biological properties and actions, as well as chemical compositions, toxicity, and pharmacokinetic and pharmacodynamic characteristics. These venoms are associated with high morbility and mortality, especially among children. Victims of envenoming by a scorpion suffer a variety of pathologies, involving mainly both sympathetic and parasympathetic stimulation as well as central manifestations such as irritability, hyperthermia, vomiting, profuse salivation, tremor, and convulsion. The clinical signs and symptoms observed in humans and experimental animals are related with an excessive systemic host inflammatory response to stings and stings, respectively. Although the pathophysiology of envenomation is complex and not yet fully understood, venom and immune responses are known to trigger the release of inflammatory mediators that are largely mediated by cytokines. In models of severe systemic inflammation produced by injection of high doses of venom or venoms products, the increase in production of proinflammatory cytokines significantly contributes to immunological imbalance, multiple organ dysfunction and death. The cytokines initiate a cascade of events that lead to illness behaviors such as fever, anorexia, and also physiological events in the host such as activation of vasodilatation, hypotension, and increased of vessel permeability.

  12. Venomous snake bites, scorpions, and spiders.

    Science.gov (United States)

    Kularatne, S A M; Senanayake, Nimal

    2014-01-01

    Neurologic dysfunction due to natural neurotoxins is an important, but neglected, public health hazard in many parts of the world, particularly in the tropics. These toxins are produced by or found among a variety of live forms that include venomous snakes, arthropods such as scorpions, spiders, centipedes, stinging insects (Hymenoptera), ticks, certain poisonous fish, shellfish, crabs, cone shells, skin secretions of dart-poison frogs, and bacterial poisons such as botulinum toxin. These toxins commonly act on neuromuscular transmission at the neuromuscular junction where acetylcholine is the neurotransmitter, but in certain situations the toxins interfere with neurotransmitters such as GABA, noradrenaline, adrenaline, dopamine, and γ-aminobutyrate. Of the toxins, α-toxins and κ-toxins (e.g., Chinese krait, Bungarus multicinctus) act on the postsynaptic membrane, blocking the receptors, whilst β-toxin (e.g., common krait, B. caeruleus) acts on the presynaptic membrane, causing impairment of acetylcholine release. Conversely, dendrotoxins of the African mamba enhance acetylcholine release. The toxins of scorpions and spiders commonly interfere with voltage-gated ion channels. Clinically, the cardinal manifestation is muscle paralysis. In severe cases respiratory paralysis could be fatal. Effective antivenoms are the mainstay of treatment of envenoming, but their lack of availability is the major concern in the regions of the globe where they are desperately needed. Interestingly, some toxins have proved to be valuable pharmaceutical agents, while some others are widely exploited to study neuromuscular physiology and pathology. © 2014 Elsevier B.V. All rights reserved.

  13. [Fifteen years' experience in scorpion envenomation control in Algeria].

    Science.gov (United States)

    Benguedda, A C; Laraba-Djébari, F; Ouahdi, M; Hellal, H; Griene, L; Guerenik, M; Laid, Y

    2002-08-01

    In Algeria, scorpion envenomation is real public health problem. Since the creation of the National Committee of Control of Scorpion envenomations (CNLES), several steps have been taken to deal with this problem. After a brief historical introduction, we present the main elements of the action carried out both in terms of treatment and of prevention of scorpion proliferation. The epidemiological situation is presented by stressing the difficulties involved in collecting reliable data. We also address the question of citizen and stakeholder awareness since public participation is crucial in all prevention programmes. Training for healthcare providers is also one of the principal axes of the Committee's programme which includes national, regional, and even local seminars. We describe the improvement of production and research on venoms carried out by the Institute Pasteur of Algeria. We conclude by discussing the action plan for 2001 and prospects for an enhanced strategy in the fight against the scorpion envenomation.

  14. Scorpion venom peptides with no disulfide bridges: a review.

    Science.gov (United States)

    Almaaytah, Ammar; Albalas, Qosay

    2014-01-01

    Scorpion venoms are rich sources of biologically active peptides that are classified into disulfide-bridged peptides (DBPs) and non-disulfide-bridged peptides (NDBPs). DBPs are the main scorpion venom components responsible for the neurotoxic effects observed during scorpion envenomation as they usually target membrane bound ion channels of excitable and non-excitable cells. Several hundred DBPs have been identified and functionally characterized in the past two decades. The NDBPs represent a novel group of molecules that have gained great interest only recently due to their high diversity both in their primary structures and bioactivities. This review provides an overview of scorpion NDBPs focusing on their therapeutic applications, modes of discovery, mechanisms of NDBPs genetic diversity and structural properties. It also provides a simple classification for NDBPs that could be adopted and applied to other NDBPs identified in future studies.

  15. Deep intraspecific divergences in the medically relevant fat-tailed scorpions (Androctonus, Scorpiones).

    Science.gov (United States)

    Coelho, P; Sousa, P; Harris, D J; van der Meijden, A

    2014-06-01

    The genus Androctonus, commonly known as fat-tailed scorpions, contains 22 species distributed from Togo and Mauritania in the west, North Africa, through the Middle East and to as far east as India. With 13 species, a substantial amount of this genus' diversity occurs in North Africa, which is a major hotspot of scorpion sting incidents. Androctonus are among the most medically relevant animals in North Africa. Since venom composition within species is known to vary regionally, the improvement of therapeutic management depends on a correct assessment of the existing regional specific and sub-specific variation. In this study, we assessed the phylogeographical patterns in six species of Androctonus scorpions from North Africa using mitochondrial DNA markers. We sequenced COX1, 12S, 16S and ND1 genes from 110 individuals. Despite lacking basal resolution in the tree, we found taxonomical and geographically coherent clades. We discovered deep intraspecific variation in the widespread Androctonus amoreuxi and Androctonus australis, which consisted of several well-supported clades. Genetic distances between some of these clades are as high as those found between species. North African A. australis have a deep split in Tunisia around the Chott el-Djerid salt-lake. A novel split between A. amoreuxi scorpions was found in Morocco. We also found deep divergences in Androctonus mauritanicus, corresponding to areas attributed to invalidated subspecies. In addition we uncovered a clade of specimens from coastal south Morocco, which could not be ascribed to any know species using morphological characters. Based on these findings we recommend a reassessment of venom potency and anti-venom efficacy between these deep intraspecific divergent clades.

  16. Scorpion sting prevention and treatment in ancient Iran

    Directory of Open Access Journals (Sweden)

    Rouhullah Dehghani

    2015-04-01

    Full Text Available Due to the medical and therapeutic importance of scorpions in Iranian traditional medicine, this review was conducted on the treatment of scorpion sting as performed by traditional healers in order to realize complications, clinical manifestations, diversities, and deficiencies in the prevention, control, and treatment as mentioned in the pertained literatures. This study tried to make known and investigate attitudes of the Iranian national and traditional medicine towards controlling these venomous animals. Keywords and articles were searched through relevant sites on the Internet. We investigated different journals and references for the Iranian traditional medicine. Based on the articles and books found, we tried to find suitable solutions to problems from the viewpoint of traditional medicine. Scorpion sting dates back to ancient Iran and has been widely reflected in the resources of Iranian traditional medicine. The traditional medicine offers various guidelines that can be beneficial in this respect. New attitude towards scorpion sting with regard to traditional medicine resources can enhance control and prevention of scorpion stings. Consequently, this attitude leads authorities and researchers to a decreased level of scorpion stings or related consequences.

  17. Scorpion Toxin Polyptides as Therapeutic Agents: An Overview.

    Science.gov (United States)

    Bhavya, Janardhan; Francois, Niyonzima N; More, Veena S; More, Sunil S

    2016-01-01

    Scorpions are distributed throughout the world and numerous biological molecules are found in their venom most importantly peptide toxins. These toxins modulate the ion channels either by blocking the pore of the channel or by altering the voltage gating. Molecules which block the pores have been useful in deciphering the structure of the ion channels. Many scorpion toxins have already been used for probing the voltage gated sodium channels and studying their activation and inactivation processes. The specialty of scorpion toxins is to discriminate between vertebrate and invertebrate channels which have led them to applications as pharmacological tools. Most of the scorpion toxin polypeptides were isolated, characterized and were shown to possess vital properties useful in the field of medicine. For instance, they show therapeutic properties such as antimicrobial activity, anticancer activity, used to treat autoimmune diseases and cardiovascular effects. Although the scorpion toxins exhibited good therapeutic effects in vitro and in vivo, no one has reached the market with success up to date. In this mini-review, the scorpion polypeptides, their interactions with ion channels and their uses as therapeutic agents are discussed.

  18. Anti-scorpion venom activity of Andrographis paniculata: A combined and comparative study with anti-scorpion serum in mice

    Directory of Open Access Journals (Sweden)

    Ranjana S Kale

    2013-01-01

    Conclusions: Present study demonstrates that, both plant extract and ASV have their own scorpion venom neutralising ability in vivo and in vitro, but their combination is most effective in venom neutralizing ability.

  19. Extreme diversity of scorpion venom peptides and proteins revealed by transcriptomic analysis: implication for proteome evolution of scorpion venom arsenal.

    Science.gov (United States)

    Ma, Yibao; He, Yawen; Zhao, Ruiming; Wu, Yingliang; Li, Wenxin; Cao, Zhijian

    2012-02-16

    Venom is an important genetic development crucial to the survival of scorpions for over 400 million years. We studied the evolution of the scorpion venom arsenal by means of comparative transcriptome analysis of venom glands and phylogenetic analysis of shared types of venom peptides and proteins between buthids and euscorpiids. Fifteen types of venom peptides and proteins were sequenced during the venom gland transcriptome analyses of two Buthidae species (Lychas mucronatus and Isometrus maculatus) and one Euscorpiidae species (Scorpiops margerisonae). Great diversity has been observed in translated amino acid sequences of these transcripts for venom peptides and proteins. Seven types of venom peptides and proteins were shared between buthids and euscorpiids. Molecular phylogenetic analysis revealed that at least five of the seven common types of venom peptides and proteins were likely recruited into the scorpion venom proteome before the lineage split between Buthidae and Euscorpiidae with their corresponding genes undergoing individual or multiple gene duplication events. These are α-KTxs, βKSPNs (β-KTxs and scorpines), anionic peptides, La1-like peptides, and SPSVs (serine proteases from scorpion venom). Multiple types of venom peptides and proteins were demonstrated to be continuously recruited into the venom proteome during the evolution process of individual scorpion lineages. Our results provide an insight into the recruitment pattern of the scorpion venom arsenal for the first time.

  20. 78 FR 32274 - Scorpion Pier Replacement Project, Channel Islands National Park, Santa Barbara County, California

    Science.gov (United States)

    2013-05-29

    ... National Park Service Scorpion Pier Replacement Project, Channel Islands National Park, Santa Barbara... analysis process for the proposed replacement and potential relocation of the existing Scorpion Pier at..., Attn: Scorpion Pier Project, 1901 Spinnaker Drive, Ventura, CA 93001 or electronically to...

  1. Biotechnological Trends in Spider and Scorpion Antivenom Development

    Science.gov (United States)

    Laustsen, Andreas Hougaard; Solà, Mireia; Jappe, Emma Christine; Oscoz, Saioa; Lauridsen, Line Præst; Engmark, Mikael

    2016-01-01

    Spiders and scorpions are notorious for their fearful dispositions and their ability to inject venom into prey and predators, causing symptoms such as necrosis, paralysis, and excruciating pain. Information on venom composition and the toxins present in these species is growing due to an interest in using bioactive toxins from spiders and scorpions for drug discovery purposes and for solving crystal structures of membrane-embedded receptors. Additionally, the identification and isolation of a myriad of spider and scorpion toxins has allowed research within next generation antivenoms to progress at an increasingly faster pace. In this review, the current knowledge of spider and scorpion venoms is presented, followed by a discussion of all published biotechnological efforts within development of spider and scorpion antitoxins based on small molecules, antibodies and fragments thereof, and next generation immunization strategies. The increasing number of discovery and development efforts within this field may point towards an upcoming transition from serum-based antivenoms towards therapeutic solutions based on modern biotechnology. PMID:27455327

  2. Biotechnological Trends in Spider and Scorpion Antivenom Development

    Directory of Open Access Journals (Sweden)

    Andreas Hougaard Laustsen

    2016-07-01

    Full Text Available Spiders and scorpions are notorious for their fearful dispositions and their ability to inject venom into prey and predators, causing symptoms such as necrosis, paralysis, and excruciating pain. Information on venom composition and the toxins present in these species is growing due to an interest in using bioactive toxins from spiders and scorpions for drug discovery purposes and for solving crystal structures of membrane-embedded receptors. Additionally, the identification and isolation of a myriad of spider and scorpion toxins has allowed research within next generation antivenoms to progress at an increasingly faster pace. In this review, the current knowledge of spider and scorpion venoms is presented, followed by a discussion of all published biotechnological efforts within development of spider and scorpion antitoxins based on small molecules, antibodies and fragments thereof, and next generation immunization strategies. The increasing number of discovery and development efforts within this field may point towards an upcoming transition from serum-based antivenoms towards therapeutic solutions based on modern biotechnology.

  3. [Use of medicinal plants against scorpionic and ophidian venoms].

    Science.gov (United States)

    Memmi, A; Sansa, G; Rjeibi, I; El Ayeb, M; Srairi-Abid, N; Bellasfer, Z; Fekhih, A

    2007-01-01

    The scorpionic and ophidian envenomations are a serious public health problem in Tunisia especially in Southeastern regions. In these regions Artemisia campestris L is a plant well known which has a very important place in traditional medicine for its effectiveness against alleged venom of scorpions and snakes. In this work, we tested for the first time, the anti-venomous activity of Artemisia campestris L against the scorpion Androctonus australis garzonii and the viper Macrovipera lebetina venoms. Assays were conducted by fixing the dose of extract to3 mg/mouse while doses of venom are variable. The leaves of Artemisia campestris L were extracted by various organic solvents (Ether of oil, ethyl acetate, methanol and ethanol) and each extract was tested for its venom neutralizing capacity. For the ethanolic extract, a significant activity with respect to the venoms of scorpion Androctonus australis garzonii (Aag), was detected. Similarly, a significant neutralizing activity against the venom of a viper Macrovipera lebetina (Ml), was obtained with the dichloromethane extract. These results suggest the presence of two different type of chemical components in this plant: those neutralizing the venom of scorpion are soluble in ethanol whereas those neutralizing the venom of viper are soluble in dichloromethane.

  4. [Scorpion stings: a public health problem in Morelos (Mexico)].

    Science.gov (United States)

    Bourée, Patrice; Frinot Joseph, P; Fernot Joseph, P; Gil, R E Morell; Fils-Aimé, F; Barrera, R Rosales; Goyffon, M

    2005-01-01

    Scorpion stings represent a major public health problem in Mexico. Their annual incidence is estimated at 150,000 cases; 800-1,000 people die from them each year, 72.5% of whom are children younger than 5 years old. The states most affected are Aguascalientes, Colima, Durango, Guanajuato, Guerrero, Jalisco, Michoacán, Morelos, Oaxaca, Puebla, Sinaloa, and Zacatecas. Morelos is an endemic zone, and scorpion stings are relatively frequent, but the indigenous population underestimates the risks. In this locality, scorpion stings lead to high morbidity, with an average of 10,219 cases each year, and a prevalence varying from 584.86 per 100,000 inhabitants in 1994 to 2043.3 per 100,000 inhabitants in 2003. Because of this upsurge, systematic medical supervision and serum therapy are necessary if scorpion poisoning is suspected in a child. The indigenous community as well as tourists visiting Mexico must be informed about the substantial risk of scorpion poisoning.

  5. Pseudouroctonus peccatum, a new scorpion from the Spring Mountains near "Sin City," Nevada (Scorpiones, Vaejovidae

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    Amanda Tate

    2013-12-01

    Full Text Available A new scorpion species is described from the Spring Mountain Range near Las Vegas, Nevada. The new species appears to be geographically isolated from other closely related species of Uroctonites Williams & Savary and Pseudouroctonus Stahnke. We tentatively place the new species in Pseudouroctonus and provide detailed descriptions and illustrations of type material. We compare the new species to 17 congeneric taxa, briefly discuss the taxonomic history of Pseudouroctonus, and provide DNA barcodes for two paratypes to assist ongoing research on the systematics of family Vaejovidae.

  6. A checklist of the scorpions of Ecuador (Arachnida: Scorpiones), with notes on the distribution and medical significance of some species.

    Science.gov (United States)

    Brito, Gabriel; Borges, Adolfo

    2015-01-01

    Ecuador harbors one of the most diverse Neotropical scorpion faunas, hereby updated to 47 species contained within eight genera and five families, which inhabits the "Costa" (n = 17), "Sierra" (n = 34), "Oriente" (n = 16) and "Insular" (n = 2) biogeographical regions, corresponding to the western coastal, Andean, Amazonian, and the Galápagos archipelago regions, respectively. The genus Tityus Koch, in the family Buthidae, responsible for severe/fatal accidents elsewhere in northern South America and the Amazonia, is represented in Ecuador by 16 species, including T. asthenes, which has caused fatalities in Colombia and Panama, and now in the Ecuadorian provinces of Morona Santiago and Sucumbíos. Underestimation of the medical significance of scorpion envenoming in Ecuador arises from the fact that Centruroides margaritatus (Gervais) (family Buthidae) and Teuthraustes atramentarius Simon (family Chactidae), whose venoms show low toxicity towards vertebrates, frequently envenom humans in the highly populated Guayas and Pichincha provinces. This work also updates the local scorpion faunal endemicity (74.5 %) and its geographical distribution, and reviews available medical/biochemical information on each species in the light of the increasing problem of scorpionism in the country. A proposal is hereby put forward to classify the Ecuadorian scorpions based on their potential medical importance.

  7. [Microbial diversity in scorpion intestine (Buthus martensii Karsch)].

    Science.gov (United States)

    Wang, Bao-Jun; Liu, Ying; Jiang, Jia-Tong; Liu, Bin; Liu, Shuang-Jiang

    2007-10-01

    Scorpion is an important officinal animal, and has a high nutritional value. In this study, the culture-independent and culture-dependent methods were used to investigate the microbial diversity in the scorpion's intestine. Results based on culture-independent method showed the bacteria to be related to alpha, beta, gamma-proteobacteria. Bacteria isolated by the culture-dependent method were high G + C, gram-positive bacteria. The genera Enterobacter, Serratia and Ochrobactrum were detected by both methods. To sum up the results from the two methods, the bacteria in scorpion intestine belong to 23 genera, which are Enterobacter, Serratia, Pseudomonas, Acinetobacter, Aeromonas, Citrobacter, Pedobacter, Delftia, Ralstonia, Ochrobactrum, Sphingomonas, Exiguobacterium, Gordonia, Nocardia, Rhodococcus, Janibacte, Kocuria, Micrococcus, Agromyces, Microbacterium, Agrococcus, Deinococcus, Ornithinimicrobium, and some uncultured species. The two methods have both advantages and shortcomings. However, when used simultaneously, they complement each other.

  8. Whole Transcriptome of the Venom Gland from Urodacus yaschenkoi Scorpion.

    Science.gov (United States)

    Luna-Ramírez, Karen; Quintero-Hernández, Verónica; Juárez-González, Víctor Rivelino; Possani, Lourival D

    2015-01-01

    Australian scorpion venoms have been poorly studied, probably because they do not pose an evident threat to humans. In addition, the continent has other medically important venomous animals capable of causing serious health problems. Urodacus yaschenkoi belongs to the most widely distributed family of Australian scorpions (Urodacidae) and it is found all over the continent, making it a useful model system for studying venom composition and evolution. This communication reports the whole set of mRNA transcripts produced by the venom gland. U. yaschenkoi venom is as complex as its overseas counterparts. These transcripts certainly code for several components similar to known scorpion venom components, such as: alpha-KTxs, beta-KTxs, calcins, protease inhibitors, antimicrobial peptides, sodium-channel toxins, toxin-like peptides, allergens, La1-like, hyaluronidases, ribosomal proteins, proteasome components and proteins related to cellular processes. A comparison with the venom gland transcriptome of Centruroides noxius (Buthidae) showed that these two scorpions have similar components related to biological processes, although important differences occur among the venom toxins. In contrast, a comparison with sequences reported for Urodacus manicatus revealed that these two Urodacidae species possess the same subfamily of scorpion toxins. A comparison with sequences of an U. yaschenkoi cDNA library previously reported by our group showed that both techniques are reliable for the description of the venom components, but the whole transcriptome generated with Next Generation Sequencing platform provides sequences of all transcripts expressed. Several of which were identified in the proteome, but many more transcripts were identified including uncommon transcripts. The information reported here constitutes a reference for non-Buthidae scorpion venoms, providing a comprehensive view of genes that are involved in venom production. Further, this work identifies new putative

  9. Microallopatry caused strong diversification in Buthus scorpions (Scorpiones: Buthidae in the Atlas Mountains (NW Africa.

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    Jan C Habel

    Full Text Available The immense biodiversity of the Atlas Mountains in North Africa might be the result of high rates of microallopatry caused by mountain barriers surpassing 4000 meters leading to patchy habitat distributions. We test the influence of geographic structures on the phylogenetic patterns among Buthus scorpions using mtDNA sequences. We sampled 91 individuals of the genus Buthus from 51 locations scattered around the Atlas Mountains (Antiatlas, High Atlas, Middle Atlas and Jebel Sahro. We sequenced 452 bp of the Cytochrome Oxidase I gene which proved to be highly variable within and among Buthus species. Our phylogenetic analysis yielded 12 distinct genetic groups one of which comprised three subgroups mostly in accordance with the orographic structure of the mountain systems. Main clades overlap with each other, while subclades are distributed parapatrically. Geographic structures likely acted as long-term barriers among populations causing restriction of gene flow and allowing for strong genetic differentiation. Thus, genetic structure and geographical distribution of genetic (subclusters follow the classical theory of allopatric differentiation where distinct groups evolve without range overlap until reproductive isolation and ecological differentiation has built up. Philopatry and low dispersal ability of Buthus scorpions are the likely causes for the observed strong genetic differentiation at this small geographic scale.

  10. Scorpion peptides: potential use for new drug development.

    Science.gov (United States)

    Hmed, Bennasr; Serria, Hammami Turky; Mounir, Zeghal Khaled

    2013-01-01

    Several peptides contained in scorpion fluids showed diverse array of biological activities with high specificities to their targeted sites. Many investigations outlined their potent effects against microbes and showed their potential to modulate various biological mechanisms that are involved in immune, nervous, cardiovascular, and neoplastic diseases. Because of their important structural and functional diversity, it is projected that scorpion-derived peptides could be used to develop new specific drugs. This review summarizes relevant findings improving their use as valuable tools for new drugs development.

  11. Scorpion Peptides: Potential Use for New Drug Development

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    BenNasr Hmed

    2013-01-01

    Full Text Available Several peptides contained in scorpion fluids showed diverse array of biological activities with high specificities to their targeted sites. Many investigations outlined their potent effects against microbes and showed their potential to modulate various biological mechanisms that are involved in immune, nervous, cardiovascular, and neoplastic diseases. Because of their important structural and functional diversity, it is projected that scorpion-derived peptides could be used to develop new specific drugs. This review summarizes relevant findings improving their use as valuable tools for new drugs development.

  12. Classification of Na channel receptors specific for various scorpion toxins.

    Science.gov (United States)

    Wheeler, K P; Watt, D D; Lazdunski, M

    1983-04-01

    1. The specific binding to rat brain synaptosomes of a radiolabelled derivative of toxin II from the scorpion Centruroides suffusus suffusus could be prevented by toxins III and IV, but not by toxin V or variants 1-3, from the venom of Centruroides sculpturatus. 2. The specific binding of a similar derivative of toxin II from Androctonus australis Hector was not affected by any of the toxins from Centruroides sculpturatus. 3. There is biochemical evidence for only two distinct classes of Na channel receptors specific for known scorpion toxins.

  13. Echocardiographic changes during acute pulmonary edema subsequent to scorpion sting

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    K Delma

    2012-01-01

    Full Text Available Acute pulmonary edema (APE occurring after scorpion sting is the leading cause of death of the victims of scorpion envenomation. The APE origin is still questioned by physicians treating these patients. Based on echocardiographic study of 20 patients with severe envenomation treated in Ouargla Hospital resuscitation ward during the last four years, the APE etiology seems more likely cardiogenic, referring to cardiac symptoms confirmed by echocardiography although other mechanisms may also be involved. This hypothesis is further confirmed by the positive response of patients to the administration of dobutamine.

  14. Structure-function relationships of scorpion neurotoxins.

    Science.gov (United States)

    Habersetzer-Rochat, C; Sampieri, F

    1976-06-01

    Chemical modification of some trifunctional amino acid residues in toxins I, II, and III of the scorpion Androctonus australis Hector have been performed. The results indicate: (1) Reduction and methylation of one disulfide bridge destroy toxic activity of toxin II. (2) The only tryptophan residue of toxin II (position 38) is not included in the active site of the molecule. (3) Modification of five carboxylates out of the seven contained in toxin II suppresses the toxic activity. (4) Acetylation of the lysine and tyrosine residues in toxin II leads to the loss of both toxic and antigenic activity. Treatment of the acetylated toxin by hydroxylamine restores partially the antigenic activity. In the case of toxin I, total acetylation abolishes only the toxic activity. It is concluded that at least one tyrosine residue must be involved in an antigenic site of toxin II. (5) Citraconylation of toxins II and III leads to complete loss of toxicity; decitraconylation restores full activity. (6) Guanidination of toxin II does not affect its toxicity significantly. (7) Alkylation of toxin II by iodoacetic acid affects both amino groups and histidine residues. The loss of toxicity is mainly due to the modification of the lysine residues. In the case of toxin I, the kinetics of toxicity loss closely parallel the covalent modification of one lysine residue.

  15. A new high-elevation scorpion species of the genus Scorpiops Peters, 1861 (Scorpiones: Euscorpiidae: Scorpiopinae) from the Himalayas, India.

    Science.gov (United States)

    Zambre, Amod; Sanap, Rajesh V; Mirza, Zeeshan A

    2014-06-01

    A new high-elevation scorpion species of the genus Scorpiops is described from the Indian state of Himachal Pradesh. Scorpiops spitiensis sp. nov. is the second highest-elevation scorpion species in Asia and the first one from India occurring at elevations above 4200 m. The new species closely resembles Scorpiops petersii, but it can be distinguished from it based on a suit of characters, one of which is the presence of 16 trichobothria on the external aspect of the patella, which is unique to the new species.

  16. A second species of Euscorpiops Vachon from caves in Vietnam (Scorpiones, Euscorpiidae, Scorpiopinae). Cave Euscorpiops scorpion from Vietnam.

    Science.gov (United States)

    Lourenço, Wilson R; Pham, Dinh-Sac

    2014-09-01

    Euscorpiops dakrong sp. n., belonging to the family Euscorpiidae Laurie, is described on the basis of one male and one female collected in the Dakrong Nature Reserve cave system, Dakrong District, Quang Tri Province, Vietnam. The new species presents most features exhibited by scorpions of the genus Euscorpiops, but it is characterized by a slender body and elongated pedipalps. This new scorpion taxon represents the second species of Scorpiopinae discovered in a cave system and may be yet another endemic element in the fauna of Vietnam. Some taxonomic propositions on the generic position of Scorpiops oligotrichus Fage, 1933 are also suggested.

  17. Leiurotoxin I (scyllatoxin), a peptide ligand for Ca2(+)-activated K+ channels. Chemical synthesis, radiolabeling, and receptor characterization

    Energy Technology Data Exchange (ETDEWEB)

    Auguste, P.; Hugues, M.; Grave, B.; Gesquiere, J.C.; Maes, P.; Tartar, A.; Romey, G.; Schweitz, H.; Lazdunski, M. (Institut de Pharmacologie du Centre National de la Recherche Scientifique, Valbonne (France))

    1990-03-15

    Leiurotoxin I (scyllatoxin) is a 31-amino acid polypeptide from the venom of the scorpion Leiurus quinquestriatus hebraeus which has been previously isolated and sequenced by others. This paper reports (i) the total synthesis of this scorpion neurotoxin as well as some aspects of its structure-function relationships; (ii) the synthesis of the analog (Tyr2)leiurotoxin I (scyllatoxin) that has been monoiodinated at high specific radioactivity (2000 Ci/mmol) and has served for the characterization of the properties of {sup 125}I-(Tyr2)leiurotoxin I binding sites (Kd = 80 pM, molecular mass of 27 and 57 kDa for two polypeptides in the leiurotoxin I binding protein); (iii) the similarity of physiological actions between leiurotoxin I and apamin. Both toxins contract Taenia coli previously relaxed with epinephrine, both toxins block the after-hyperpolarization due to Ca2(+)-activated K+ channel activity in muscle cells in culture; (iv) the probable identity of binding sites for apamin and leiurotoxin I. In spite of a different chemical structure apamin competitively inhibits {sup 125}I-(Tyr2) leiurotoxin I binding and vice versa. Moreover, the peculiar effects of K+ on {sup 125}I-(Tyr2)leiurotoxin I binding are identical to those previously observed for {sup 125}I-apamin binding.

  18. Investigations on the role of insulin and scorpion antivenom in scorpion envenoming syndrome

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    K. Radha Krishna Murthy

    2003-01-01

    Full Text Available Acute myocardiopathy in alloxan treated experimental dogs and rabbits was induced by subcutaneous (SQ injection of scorpion venom from Mesobuthus tamulus concanesis, Pocock. Envenoming resulted in an initial transient hypertension (180-320 mm Hg. followed by hypotension. Simultaneous administration of venom and species-specific scorpion antivenom (SAV prevented hypertension and hypotension. Hypotension did not occur when SAV was given 60 min after envenoming. Blood glucose, triglycerides, cholesterol, amylase, insulin, glucagon, cortisol, hematocrit, mean corpuscular volume (MCV, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, platelet count, red blood cell (RBC count, hemoglobin (Hb, 2,3-diphosphoglycerate (2,3-DPG, and glutathione levels were increased 60 and 90 min after envenoming. Total white blood cell (WBC count was reduced 60 min and increased 90 min after envenoming. Simultaneous administration of venom and SAV did not alter Hb, MCHC, and packed cell volume (PCV levels, or ECG, and cardiovascular, biochemical, metabolic, and hormonal changes. Hematological parameters were reversed when SAV was given 30 and 60 min after envenoming. PCV, Hb, and MCHC values returned to normal 120 min after SAV. Alloxan-treated dogs showed increased blood glucose, cholesterol, glucagon, cortisol levels; reduced glycogen content of liver, cardiac and skeletal muscles; and reduced insulin levels and insulin/ glucagon ratio (I/G ratio. Envenoming in the alloxan pre-treated dogs further increased these levels and reduced tissue glycogen content, insulin levels, and I/G ratio. Administration of 4 U of insulin to alloxan pre-treated envenomed rabbits caused a biochemical and clinical improvement and increased glycogen content of all tissues in comparison with the values from those administered with SAV to alloxan pre-treated envenomed animals. SAV administration to envenomed alloxan pre-treated rabbits did not cause clinical or

  19. The ultrastructure of book lung development in the bark scorpion Centruroides gracilis (Scorpiones: Buthidae

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    Farley Roger D

    2011-07-01

    Full Text Available Abstract Background Near the end of the nineteenth century the hypothesis was presented for the homology of book lungs in arachnids and book gills in the horseshoe crab. Early studies with the light microscope showed that book gill lamellae are formed by outgrowth and possibly some invagination (infolding of hypodermis (epithelium from the posterior surface of opisthosomal limb buds. Scorpion book lungs are formed near the bilateral sites of earlier limb buds. Hypodermal invaginations in the ventral opisthosoma result in spiracles and sac-like cavities (atria. In early histological sections of embryo book lungs, widening of the atrial entrance of some lamellae (air channels, air sacs, saccules was interpreted as an indication of invagination as hypothesized for book gill lamellae. The hypodermal infolding was thought to produce the many rows of lamellar precursor cells anterior to the atrium. The ultrastructure of scorpion book lung development is compared herein with earlier investigations of book gill formation. Results In scorpion embryos, there is ingression (inward migration of atrial hypodermal cells rather than invagination or infolding of the atrial hypodermal layer. The ingressing cells proliferate and align in rows anterior to the atrium. Their apical-basal polarity results in primordial air channels among double rows of cells. The cuticular walls of the air channels are produced by secretion from the apical surfaces of the aligned cells. Since the precursor cells are in rows, their secreted product is also in rows (i.e., primordial air channels, saccules. For each double row of cells, their opposed basal surfaces are gradually separated by a hemolymph channel of increasing width. Conclusions The results from this and earlier studies show there are differences and similarities in the formation of book lung and book gill lamellae. The homology hypothesis for these respiratory organs is thus supported or not supported depending on which

  20. Incidence and severity of scorpion stings in Algeria

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    Y Laïd

    2012-01-01

    Full Text Available Scorpion stings are a public health problem in the Maghreb region. In Algeria, epidemiological data were collected over the past twenty years by the Algerian health authorities. This study is an analysis of morbidity and mortality data collected from 2001 to 2010. Annual incidence and mortality due to scorpion envenoming were 152 ± 3.6 stings and 0.236 ± 0.041 deaths per 100,000 people (95% CI, respectively. The risk of being stung by a scorpion was dramatically higher in southern areas and central highlands due to environmental conditions. Incidence of envenoming was especially higher in the adult population, and among young males. In contrast, mortality was significantly higher among children under 15 years, particularly ages 1-4. Upper limbs were more often affected than lower limbs. Most stings occurred at night, indoors and during the summer. Data collected since 2001 showed a reduction of mortality by nearly 50%, suggesting that the medical care defined by the national anti-scorpion project is bearing fruit.

  1. Hox gene duplications correlate with posterior heteronomy in scorpions.

    Science.gov (United States)

    Sharma, Prashant P; Schwager, Evelyn E; Extavour, Cassandra G; Wheeler, Ward C

    2014-10-07

    The evolutionary success of the largest animal phylum, Arthropoda, has been attributed to tagmatization, the coordinated evolution of adjacent metameres to form morphologically and functionally distinct segmental regions called tagmata. Specification of regional identity is regulated by the Hox genes, of which 10 are inferred to be present in the ancestor of arthropods. With six different posterior segmental identities divided into two tagmata, the bauplan of scorpions is the most heteronomous within Chelicerata. Expression domains of the anterior eight Hox genes are conserved in previously surveyed chelicerates, but it is unknown how Hox genes regionalize the three tagmata of scorpions. Here, we show that the scorpion Centruroides sculpturatus has two paralogues of all Hox genes except Hox3, suggesting cluster and/or whole genome duplication in this arachnid order. Embryonic anterior expression domain boundaries of each of the last four pairs of Hox genes (two paralogues each of Antp, Ubx, abd-A and Abd-B) are unique and distinguish segmental groups, such as pectines, book lungs and the characteristic tail, while maintaining spatial collinearity. These distinct expression domains suggest neofunctionalization of Hox gene paralogues subsequent to duplication. Our data reconcile previous understanding of Hox gene function across arthropods with the extreme heteronomy of scorpions.

  2. Seeking Refuge in Literacy from a Scorpion Bite

    Science.gov (United States)

    Sarroub, Loukia K.

    2007-01-01

    The purpose of this study is to examine a refugee boy's experiences with literacy in and out of school in the US. Within these contexts, I explore this youth's literacy development in light of his identity as a poor Yezidi Kurdish refugee from Iraq. Central to the article are two main themes. The first, life as a scorpion sting, explicates the…

  3. Exon Shuffling and Origin of Scorpion Venom Biodiversity

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    Xueli Wang

    2016-12-01

    Full Text Available Scorpion venom is a complex combinatorial library of peptides and proteins with multiple biological functions. A combination of transcriptomic and proteomic techniques has revealed its enormous molecular diversity, as identified by the presence of a large number of ion channel-targeted neurotoxins with different folds, membrane-active antimicrobial peptides, proteases, and protease inhibitors. Although the biodiversity of scorpion venom has long been known, how it arises remains unsolved. In this work, we analyzed the exon-intron structures of an array of scorpion venom protein-encoding genes and unexpectedly found that nearly all of these genes possess a phase-1 intron (one intron located between the first and second nucleotides of a codon near the cleavage site of a signal sequence despite their mature peptides remarkably differ. This observation matches a theory of exon shuffling in the origin of new genes and suggests that recruitment of different folds into scorpion venom might be achieved via shuffling between body protein-coding genes and ancestral venom gland-specific genes that presumably contributed tissue-specific regulatory elements and secretory signal sequences.

  4. Insights into Antimicrobial Peptides from Spiders and Scorpions.

    Science.gov (United States)

    Wang, Xiuqing; Wang, Guangshun

    2016-01-01

    The venoms of spiders and scorpions contain a variety of chemical compounds. Antimicrobial peptides (AMPs) from these organisms were first discovered in the 1990s. As of May 2015, there were 42 spider's and 63 scorpion's AMPs in the Antimicrobial Peptide Database (http://aps.unmc.edu/AP). These peptides have demonstrated broad or narrow-spectrum activities against bacteria, fungi, viruses, and parasites. In addition, they can be toxic to cancer cells, insects and erythrocytes. To provide insight into such an activity spectrum, this article discusses the discovery, classification, structure and activity relationships, bioinformatics analysis, and potential applications of spider and scorpion AMPs. Our analysis reveals that, in the case of linear peptides, spiders use both glycine-rich and helical peptide models for defense, whereas scorpions use two distinct helical peptide models with different amino acid compositions to exert the observed antimicrobial activities and hemolytic toxicity. Our structural bioinformatics study improves the knowledge in the field and can be used to design more selective peptides to combat tumors, parasites, and viruses.

  5. Oral Absorption of Mesobuthus eupeus Scorpion Venom in Mice

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    Zohreh Hosseini

    2017-02-01

    Full Text Available Background: To explore the oral absorption of scorpion venom an ELISA were designed in this study. Scorpions and their venom were been used for centuries as medical treatments in traditional medicine. The oral administration of drug referred as the convenient way, as there was not any publication about gastro-intestinal absorption of scorpion venom; this experiment checked oral absorption of Mesobuthus eupeus scorpion venom in mice. Methods: Six groups of mice orally received 0, 0.2, 0.5, 1, 2 and 5 mg/kg of M. eupeus venom and their blood samples were tacked after 15, 30, 60 min and 2, 4, 6, 24, 48 h after that. The presence of venom the blood samples were detected with a house- antigen capture ELISA. Results: The venom was absorbed after its feeding to mice. The animals expressed no signs of envenomation and, the venom was detectable by AC-ELISA as soon as 15 min after its feed. Maximum serum levels were 2 h after its meal. Conclusion: The orally administrated venom was absorbed to the blood circulation without any clinically symptoms.

  6. Biotechnological Trends in Spider and Scorpion Antivenom Development

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard; Solà, Mireia; Jappe, Emma Christine;

    2016-01-01

    Spiders and scorpions are notorious for their fearful dispositions and their ability to inject venom into prey and predators, causing symptoms such as necrosis, paralysis, and excruciating pain. Information on venom composition and the toxins present in these species is growing due to an interest...

  7. Fine structural analysis of the stinger in venom apparatus of the scorpion Euscorpius mingrelicus (Scorpiones: Euscorpiidae

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    N Yigit

    2010-01-01

    Full Text Available In this study, the morphology, histology and fine structure of the stinger, a part of the venom apparatus of Euscorpius mingrelicus (Kessler, 1874 (Scorpiones: Euscorpiidae were studied by light microscopy and transmission electron microscopy (TEM. The stinger, located at the end section of the telson, is sickle-shaped. The venom is ejected through a pair of venom pores on its subterminal portion. Both venom ducts extend along the stinger without contact with each other since they are separated by connective tissue cells. The stinger cuticle is composed of two layers. Additionally, there are many pore canals and some hemolymph vessels in the cuticle. This work constitutes the first histological and fine structure study on Euscorpius mingrelicus stinger.

  8. Growth and developmental time in the parthenogenetic scorpion Tityus stigmurus (Thorell, 1876 (Scorpiones: Buthidae

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    Adriano Medeiros de Souza

    2016-07-01

    Full Text Available This study describes variation in ontogenetic development of the parthenogenetic scorpion Tityus stigmurus based on variations in size, intermolt period, and number of instars. Individuals were created under laboratory conditions (28 ± 3ºC and subjected to similar diet regime. Comparative measurements of carapace, segment V of the metasoma, and the movable finger are used to estimate variations in size among instars. The application of Dyar rule shows a growth factor from 1.14 to 1.38 depending on the parameter analysed with intense variations in size between and within the different instars. The duration of the period from birth to adulthood was 871 days, after six moults. These data suggest that T. stigmurus has the longest post-embryonic development of Tityus genus and the existence of an extra molt to reach maturity.

  9. The roles of some scorpions, Hemiscorpius lepturus and Androctonus crassicauda, in a scorpionism focus in Ramhormorz, southwestern Iran.

    Science.gov (United States)

    Mohseni, Alireza; Vazirianzadeh, Babak; Hossienzadeh, Mohsen; Salehcheh, Maryam; Moradi, Azra; Moravvej, Seyed Abbas

    2013-01-01

    Scorpion stings are a common and important health problem in Iran, particularly in south and southwestern Iran, including the province of Khuzestan. In the area of Khuzestan near the city of Ramhormoz, Hemiscorpius lepturus (Scorpionida: Hemiscorpioiidae) and Androctonus crassicauda (Buthidae) are present. Ramhormoz is in southwestern Iran and is one of the most important foci of the scorpion sting problem. The current study was carried out to gain both epidemiological and medical information about scorpion stings in and around the city of Ramhormoz. In total, 179 people who were admitted to the Emergency Department of Ramhormoz Imam Khomeini Hospital during 2008 and 2009 after being stung by scorpions were monitored. Epidemiological and medical parameters including sex of the victim; the part of the body stung; the month when stung; the biochemical parameters comprising blood sugar (BS), blood urea nitrogen (BUN), and creatinine (CR); hematological parameters including white blood cells (WBC), count blood cells (CBC), red blood cells (RBC), hemoglobin (Hb), hematocrit (HCT), platelet (PLT); and urine analysis including hemoglobinuria were recorded. The current study showed that most of the victims were stung by H. lepturus, while very few were stung by A. crassicaud, but in over half of the cases the species was not known. Stings were most common from May to Aguust. 73% of the victims were female. The limbs were the part of the body most likely to be stung. Hemogobinuria was very common in H. lepturus victims.

  10. Severity of Scorpion Stings in the Western Brazilian Amazon: A Case-Control Study

    OpenAIRE

    Queiroz, Amanda M.; Vanderson S Sampaio; Iran Mendonça; Nelson F. Fé; Jacqueline Sachett; Luiz Carlos L. Ferreira; Esaú Feitosa; Fan Hui Wen; Marcus Lacerda; Wuelton Monteiro

    2015-01-01

    Background Scorpion stings are a major public health problem in Brazil, with an increasing number of registered cases every year. Affecting mostly vulnerable populations, the phenomenon is not well described and is considered a neglected disease. In Brazil, the use of anti-venom formulations is provided free of charge. The associate scorpion sting case is subject to compulsory reporting. This paper describes the epidemiology and identifies factors associated with severity of scorpions stings ...

  11. Tityus bahiensis scorpion venom injected to dams during pregnancy affects some cytokines of fetuses.

    Science.gov (United States)

    Dorce, Ana L C; Frare, Eduardo O; Paulo, Maria E F V; Dorce, Valquiria A C; Nencioni, Ana L A

    2015-09-01

    Due to the high incidence of scorpion stings in Brazil, pregnant women are among the possible victims. Cytokines are important during the pregnancy, and scorpion venoms can change their release. We evaluated the levels of some cytokines in the fetuses after the treatment of pregnant rats with the Tityus bahiensis scorpion venom. The concentration of some of them is altered and can be responsible for the effects previously observed on innate reflexes, and the physical and behavioral development of the offspring.

  12. Study of scorpion fauna in Abomosa, Great & Small Tonbs and Hengam Islands of the Persian Gulf

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    Jamil Zargan

    2003-09-01

    Full Text Available In tropical regions of Iran, scorpion’s envenomation is counted one of the most important medical difficulties. Without information or attention to fauna and activity seasonal in a zone, adopting alike prophylactic or control methods to various species of scorpions, in more cases are unsuccessful. According to the kind of habitat of digging and non-digging scorpions, for scorpions collecting, probable refuges were searched by two methods daily searching and UV lamp at night in various zones of Abomosa , Great & Small Tonbs and Hengam Islands. The Scorpions were transferred to the laboratory and were identified and appointed their sex ratio. In this study, 311 and 134 scorpions were collected from Abumosa and Great Tonb, respectively and all of them were classified as Buthotus jayakari. In our study we could’nt find any scorpion. In Hengam island 155 scorpions were collected, that 134 and 21 scorpions respectively were belong to B. jayakari and Mesobuthus eupeus species. In conclusion B. jayakari and M. eupeus are scorpion fauna in the Persian Gulf Islands.

  13. Spatial Distribution of Scorpion Sting in a High-Risk Area of Southern Iran.

    Science.gov (United States)

    Shahi, Mehran; Moosavy, Seyed Hamid; Hanafi-Bojd, Ahamd Ali; Navidpour, Shahrokh; Zare, Shahram; Madani, Abdolhossein; Rafinejad, Javad

    2016-06-16

    Scorpion sting is a public health problem in south and southwestern parts of Iran, with about 36,000 cases recorded annually. This study aimed to find the spatial distribution of scorpions and their stings in Bandar Abbas County. Monthly scorpion sting cases at the village level were obtained and used for mapping. Scorpions were collected from 14 collection sites using a UV lamp at night and searching under stones during the day time. During the study period, a total of 3,971 cases of scorpion sting were recorded, most of them were found in mountainous areas and affected individuals aged 25-44 yrs. In total, 18 scorpion species belonging to 10 genera were collected and identified. The peak of scorpion sting cases occurred from July to September. The northern part of the mountainous areas had a richer species composition. Hemiscorpius persicus and Hemiscorpius gaillardi were collected for the first time in the area. There were 22 scorpion species in the area across studies; among them, 10 were most dangerous. Hemiscorpius genus is the main etiologic agent in Bandar Abbas County. Mapping dangerous species allows the health system to provide relevant anti-scorpion venom serum accordingly and more cost-effectively.

  14. Pediatric epidemiological aspects of scorpionism and report on fatal cases from Tityus stigmurus stings (Scorpiones: Buthidae in State of Pernambuco, Brazil

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    Cleide Maria Ribeiro de Albuquerque

    2013-08-01

    Full Text Available Introduction Envenomation by scorpion stings is a major public health problem in numerous tropical countries because of its frequent incidence and potential severity. Approximately 1,900 species of scorpions are known in the world, and at least 130 of these have been described in Brazil. Methods This work reports on 3 child deaths caused by Tityus stigmurus stings and characterizes epidemiological and clinical surveys on pediatric cases of scorpionism recorded in the Centro de Assistência Toxicológica de Pernambuco (Ceatox-PE. Results Scorpion stings accounted for more than 60% of all cases recorded for venomous animals. The children were from 37 cities of the Pernambuco state and accounted for 28.8% of the victims treated for scorpion stings, with the highest incidence in the metropolitan area of Recife. Stings occurred throughout the year and slightly increased during the rainy season. Independent of the elapsed time for a prognosis, most cases showed mild symptoms. Three moderate cases that resulted in death featured cardiogenic shock and/or pulmonary edema or severe neurological symptoms. For the first time, death attributed to T. stigmurus was confirmed by the presence of the scorpion. Conclusions These results suggest that scorpionism in Pernambuco is a public health problem that needs to be monitored carefully throughout the year by the government.

  15. Posterior reversible encephalopathy syndrome following a scorpion sting.

    Science.gov (United States)

    Porcello Marrone, Luiz Carlos; Marrone, Bianca Fontana; Neto, Felipe Kalil; Costa, Francisco Cosme; Thomé, Gustavo Gomes; Aramburu, Martin Brandolt; Schilling, Lucas Porcello; Pascoal, Tharick Ali; Gadonski, Giovani; Huf Marrone, Antônio Carlos; da Costa, Jaderson Costa

    2013-10-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic entity not yet understood, that is present with transient neurologic symptoms and particular radiological findings. The most common imaging pattern in PRES is the presence of edema in the white matter of the posterior portions of both cerebral hemispheres. The cause of PRES is unclear. We report a case of 13-year-old male who was stung by a scorpion and developed a severe headache, visual disturbance, and seizures and had the diagnosis of PRES with a good outcome. Numerous factors can trigger this syndrome, most commonly: acute elevation of blood pressure, abnormal renal function, and immunosuppressive therapy. There are many cases described showing the relationship between PRES and eclampsia, transplantation, neoplasia and chemotherapy treatment, systemic infections, renal disease acute, or chronic. However, this is the first case of PRES following a scorpion sting.

  16. ADAMTS-13 deficiency following Hemiscorpius lepturus scorpion sting

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    Ehsan Valavi

    2011-01-01

    Full Text Available Hemiscorpius lepturus is a lethal scorpion with potentially cytotoxic venom. Various degrees of local and systemic toxicity have been observed after its envenomation ranging from local erythema to disseminated intravascular coagulation, renal failure and severe pulmonary hemorrhage. In this case report, we report on a seven-year-old patient who developed the hemolytic uremic syndrome (HUS after being stung by the scorpion H. lepturus. This condition is characterized by microangiopathic hemolytic anemia, thrombocytopenia, increased serum levels of lactate dehydrogenase and uremia. We evaluated the causes of HUS and found that the levels of C3, C4, CH50 and H factors were normal, but the activity of Von Willebrand factor cleaving protease was decreased (less than 5% of the normal activity. The patient improved after administering therapy with plasma exchange.

  17. Scorpion venoms: taking the sting out of lung disease.

    OpenAIRE

    1996-01-01

    Scorpion venoms contain specific toxins which block large conductance calcium-activated potassium (BKCa) channels. Use of these toxins has shown that a significant proportion of the action of bronchodilators such as beta-agonists, theophylline, and nitric oxide occurs as a result of the opening of BKCa channels. Similarly, these toxins have shown that inhibitors of airway neurotransmission also operate via BKCa channels. Drugs that open BKCa channels may be alternative bronchodilators (possib...

  18. Pediatric electrocardiograph abnormalities following Centruroides limpidus tecomanus scorpion envenomation.

    Science.gov (United States)

    Diaz, P; Chowell, G; Ceja, G; D'Auria, T C; Lloyd, R C; Castillo-Chavez, C

    2005-01-01

    Scorpionism is an endemic public health problem in Mexico [Hoffmann, C.C., 1936. La distribucion geografica de los alacranes peligrosos en la Republica Mexicana. Bol. Inst. Hygiene Mex. 2, 321; Hoffmann, C.C., Nieto, D.R., 1939. Segunda contribucion al conocimiento de los alacranes mexicanos. Anal. Inst. Biol. 10, 83-92; Mazzoti, L., Bravo-Becherelle, M.A., 1963. Scorpionism in the Mexican Republic. In: Keegan, H.L., McFarlane, W.V. (Eds.), Venomous and Poissonous Animals and Noxious Plants of the Pacific Area. Pergamon Press, London, pp. 119-131; Monroy-Velasco, J., 1961. Alacranes venenosos de Mexico. Rev. Mex. Cien. Med. Biol., Mex. 1, 1-23; Diaz-Najera, A., 1975. Listas y datos de distribucion geografica de los alacranes de Mexico. Rev. Inv. Salud. Publica. (Mex.) 35, 1; Velasco-Castrejon, O., Lara-Aguilera, R., Alatorre, H., 1976. Aspectos epidemiologicos y clinicos de la picadura de alacran en una area hiperendemica. Rev. Inv. Salud Publica. (Mex.) 36, 93-103; Dehesa-Davila, M., Possani, L.D., 1994. Scorpionism and serotherapy in Mexico. Toxicon 32 (9), 1015-1018]. In this prospective study, we assess cardiovascular disorders in children via electrocardiographic (ECG) recordings following envenomation by scorpion species Centruroides limpidus tecomanus found in the state of Colima, Mexico. We analyzed 113 cases between the ages of 5 and 14 years. Among the most frequent symptoms presented included local pain (99.1%) and paresthesia (75.2%), pruritus (36.3%), sialorrhoea (35.4%), and nystagmus (24.8%). Cardiovascular disorders were observed in 39.8% of cases, 71% of which were rhythm abnormalities. We find a significant association between the frequency of ECG alterations and age, whereby 8-9-year-old children are more likely to experience ECG alterations when compared with other tested age groups.

  19. Transcriptome analysis of scorpion species belonging to the Vaejovis genus.

    Science.gov (United States)

    Quintero-Hernández, Verónica; Ramírez-Carreto, Santos; Romero-Gutiérrez, María Teresa; Valdez-Velázquez, Laura L; Becerril, Baltazar; Possani, Lourival D; Ortiz, Ernesto

    2015-01-01

    Scorpions belonging to the Buthidae family have traditionally drawn much of the biochemist's attention due to the strong toxicity of their venoms. Scorpions not toxic to mammals, however, also have complex venoms. They have been shown to be an important source of bioactive peptides, some of them identified as potential drug candidates for the treatment of several emerging diseases and conditions. It is therefore important to characterize the large diversity of components found in the non-Buthidae venoms. As a contribution to this goal, this manuscript reports the construction and characterization of cDNA libraries from four scorpion species belonging to the Vaejovis genus of the Vaejovidae family: Vaejovis mexicanus, V. intrepidus, V. subcristatus and V. punctatus. Some sequences coding for channel-acting toxins were found, as expected, but the main transcribed genes in the glands actively producing venom were those coding for non disulfide-bridged peptides. The ESTs coding for putative channel-acting toxins, corresponded to sodium channel β toxins, to members of the potassium channel-acting α or κ families, and to calcium channel-acting toxins of the calcin family. Transcripts for scorpine-like peptides of two different lengths were found, with some of the species coding for the two kinds. One sequence coding for La1-like peptides, of yet unknown function, was found for each species. Finally, the most abundant transcripts corresponded to peptides belonging to the long chain multifunctional NDBP-2 family and to the short antimicrobials of the NDBP-4 family. This apparent venom composition is in correspondence with the data obtained to date for other non-Buthidae species. Our study constitutes the first approach to the characterization of the venom gland transcriptome for scorpion species belonging to the Vaejovidae family.

  20. Clinical and cardiovascular alterations produced by scorpion envenomation in dogs

    Directory of Open Access Journals (Sweden)

    F. F. Cordeiro

    2006-01-01

    Full Text Available Scorpionism is a common problem that occurs in tropical and subtropical countries and assumes great medical-sanitary importance due to its fatal effect on sensitive individuals, being able to lead children and aged people to death. The envenomation lethal potential is responsible for the serious cardiopulmonary alterations the scorpion toxin produces in its victims. The present research evaluated the effects of Tityus serrulatus venom on dogs, using two distinct doses: a dose that simulates natural envenomation (0.4 mg/total dose, and an experimental dose (0.25 mg/kg. General clinical signs were observed at different moments after envenomation, and specific data related to the cardiopulmonary system were evaluated by systemic arterial pressure measurement, CK-MB enzymatic activity dosage, and radiographic, electrocardiographic and echocardiographic examinations. Results demonstrated that the scorpion venom, in experimental doses, was able to cause acute and reversible cardiac injury in few days, and, in the dose that simulated natural accident, it produced clinical signs of light envenomation, such as local pain, hyperesthesia, sialorrhea, vomiting, diarrhea, sneeze and prostration.

  1. The "SCORPION" experiment onboard the International Space Station. Preliminary results.

    Science.gov (United States)

    Borisov, V; Deshevaya, E; Grachov, E; Grigoryan, O; Tchurilo, I; Tsetlin, V

    2003-01-01

    The "SCORPION" program onboard the Russian Segment (RS) of the International Space Station (ISS) is designed to carry out complex research of the effects of the nar-Earth space parameters on the conditions under which various experiments and operations are being conducted. Special attention in this program was paid to the biological objects onboard the orbital station, e.g. it was found that variation in the number of colony forming units (micromicets and bacteria) correlates with the solar activity and the absorbed dose. The "SCORPION" experiment onboard the RS ISS started in January 2002. It was designed to measure the following parameters inside the space absorbed doses in different places inside the RS ISS, the fluxes of energetic charged particles, neutrons and gamma-quanta; the vectors of the magnetic field and low-frequency electromagnetic waves. At the same time the growth of micromicets on the samples of various materials was studied. The description of the "SCORPION" experiment and the preliminary results obtained onboard the RS ISS in 2002 are presented.

  2. Three new antimicrobial peptides from the scorpion Pandinus imperator.

    Science.gov (United States)

    Zeng, Xian-Chun; Zhou, Lingli; Shi, Wanxia; Luo, Xuesong; Zhang, Lei; Nie, Yao; Wang, Jinwei; Wu, Shifen; Cao, Bin; Cao, Hanjun

    2013-07-01

    Three novel cysteine-free venom peptides, which were referred to as Pantinin-1, Pantinin-2 and Pantinin-3, respectively, have been identified from the scorpion Pandinus imperator by cDNA cloning strategy. The precursor of each peptide consists of a signal peptide, a mature peptide with no disulfide bridges, and an acidic propeptide with a typical processing signal. Each of the three peptides is an α-helical, cationic and amphipathic molecule with 13 or 14 amino acid residues. Their amino acid sequences are homologous to those of some 13-mer antimicrobial peptides isolated from scorpions. Antimicrobial assay showed that all the three peptides possess relatively strong activities against Gram-positive bacteria and a fungus, but have very weak antimicrobial activities against Gram-negative bacteria. Toxicity assay showed that the three peptides exhibit very low or mild hemolytic activities against human red blood cells. It is interesting to see that Pantinin-3 is able to potently inhibit the growth of vancomycin-resistant Enterococcus (VRE) S13, a pathogen that can cause a number of human infections; this suggests that Pantinin-3 has great potential to be applied in the treatment of VRE infections. Our findings gain new insights into the structure/function relationships of the small linear cationic antimicrobial peptides from scorpions, and provide new templates for designing of antimicrobial agents targeting antibiotic-resistant pathogenic bacteria.

  3. Embryotoxicity following repetitive maternal exposure to scorpion venom

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    BN Hmed

    2012-01-01

    Full Text Available Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L than in those receiving saline solution (4.94 ± 0.90 mmol/L. Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g than in the others (3.0 ± 0.2 g. Subcutaneous blood clots, microphthalmia and total body and tail shortening were also observed in venom-treated fetuses. It is concluded that scorpion envenomation during pregnancy potentially causes intrauterine fetal alterations and growth impairment.

  4. Erosion resistance of bionic functional surfaces inspired from desert scorpions.

    Science.gov (United States)

    Zhiwu, Han; Junqiu, Zhang; Chao, Ge; Li, Wen; Ren, Luquan

    2012-02-01

    In this paper, a bionic method is presented to improve the erosion resistance of machine components. Desert scorpion (Androctonus australis) is a typical animal living in sandy deserts, and may face erosive action of blowing sand at a high speed. Based on the idea of bionics and biologic experimental techniques, the mechanisms of the sand erosion resistance of desert scorpion were investigated. Results showed that the desert scorpions used special microtextures such as bumps and grooves to construct the functional surfaces to achieve the erosion resistance. In order to understand the erosion resistance mechanisms of such functional surfaces, the combination of computational and experimental research were carried out in this paper. The Computational Fluid Dynamics (CFD) method was applied to predict the erosion performance of the bionic functional surfaces. The result demonstrated that the microtextured surfaces exhibited better erosion resistance than the smooth surfaces. The further erosion tests indicated that the groove surfaces exhibited better erosion performance at 30° injection angle. In order to determine the effect of the groove dimensions on the erosion resistance, regression analysis of orthogonal multinomials was also performed under a certain erosion condition, and the regression equation between the erosion rate and groove distance, width, and height was established.

  5. Midbrain enkephalin expression in a rat migraine model following intragastric scorpion powder administration

    Institute of Scientific and Technical Information of China (English)

    Gang Yao; Xiangdan Luo; Dihui Ma; Tingmin Yu

    2011-01-01

    Scorpion has strong analgesic effects, but its analgesic mechanisms remain unclear. This study investigated the effects of scorpion powder on enkephalin expression in the midbrain of rats with nitroglycerin-induced migraine at mRNA and protein levels. Results confirmed that migraine rat abnormal behavior was significantly improved, and proenkephalin mRNA expression was significantly increased following treatment with scorpion. The number of methionine-enkephalin- positive cells in the migraine rats following treatment with scorpion was significantly increased, but no significant difference in the number of leucine-enkephalin-positive cells was detectable compared with migraine and normal rats. Taken together, these results show that scorpion exerts potentially beneficial effects by promoting enkephalin expression in nitroglycerin-induced migraine rats.

  6. A new species of the rare buthid scorpion genus Lissothus Vachon, 1948 from Central Algeria (Scorpiones, Buthidae).

    Science.gov (United States)

    Lourenço, Wilson Roberto; Sadine, Salah Eddine

    2014-06-01

    Taxonomic considerations are given for the genus Lissothus Vachon, 1948 (Scorpiones, Buthidae). Two species are currently known, Lissothus bernardi Vachon, 1948 from Libya and Lissothus occidentalis Vachon, 1950 from Mauritania. In this contribution, a new species, Lissothus chaambi sp. n., is described from the desert of Central Algeria. The new species is most closely related to L. bernardi. The geographical distribution of the genus is discussed.

  7. Male and female meiosis in the mountain scorpion Zabius fuscus (Scorpiones, Buthidae): heterochromatin, rDNA and TTAGG telomeric repeats.

    Science.gov (United States)

    Adilardi, Renzo Sebastián; Ojanguren-Affilastro, Andrés Alejandro; Mattoni, Camilo Iván; Mola, Liliana María

    2015-08-01

    All cytogenetically studied scorpions present male achiasmatic meiosis and lack heteromorphic sex chromosomes. In contrast, information about female meiosis in scorpions is scarce due to the difficulty of finding meiotic cells. The genus Zabius includes three described species and no chromosome studies have been performed on it until now. We analyzed the constitutive heterochromatin distribution, NORs and telomeric sequences in mitosis and meiosis of males and females of different populations of Zabius fuscus. All specimens presented 2n = 18 holokinetic chromosomes that gradually decreased in size. Male meiosis presented nine bivalents and a polymorphism for one reciprocal translocation in one population. Telomeric signals were detected at every terminal region, confirming also the presence of a (TTAGG) n motif in Buthidae. Constitutive heterochromatin was found in three chromosome pairs at a terminal region; moreover, NORs were embedded in the heterochromatic region of the largest pair. Chromosome size and landmarks allowed us to propose the chromosomes involved in the rearrangement. In four females, cells at different prophase I stages were analyzed. We describe a diffuse stage and the presence of ring-shaped bivalents. We discuss the possible origin of these bivalents in the framework of chiasmatic or achiasmatic female meiosis. These results contribute to increase the scarce evidence of female meiosis in scorpions and raise new questions about its mechanism.

  8. Recombinant expression, functional characterization of two scorpion venom toxins with three disulfide bridges from the Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Lin, ShengGuo; Wang, XueLin; Hu, XueYao; Zhao, YongShan; Zhao, MingYi; Zhang, JingHai; Cui, Yong

    2017-01-17

    Scorpion venom contains a large variety of biologically active peptides. However, most of these peptides have not been identified and characterized. Peptides with three disulfide bridges, existing in the scorpion venom, have not been studied in detail and have been poorly characterized until now. Here, we report the recombinant expression and functional characterization of two kinds of venom peptides (BmKBTx and BmNaL-3SS2) with three disulfide bridges. This study adopted an effective E. coli system. The genes for BmKBTx and BmNaL-3SS2 were obtained by the Polymerase Chain Reaction method and finally cloned to the pSYPU-1b vector. After expression and purification, the two recombinant proteins underwent an analgesic activity assay in mice and whole-cell patch-clamp recording of hNav1.7-CHO cell lines. Functional tests showed that BmKBTx and BmNaL-3SS2 have analgesic activity in mice and can interact with the hNav1.7 subtype of the voltage-gated sodium channel (VGSC). Scorpion venom is rich in bioactive proteins, but most of their functions are unknown to us. This study has increased our knowledge of these novel disulfide-bridged peptides (DBPs) and their biological activities.

  9. Maintenance of scorpions of the genus Tityus Koch (Scorpiones, Buthidae for venom obtention at Instituto Butantan, São Paulo, Brazil

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    D. M. Candido

    2004-01-01

    Full Text Available This work presents the experience of the Laboratory of Arthropods at Instituto Butantan, which maintains scorpions in captivity in order to obtain the venom used in the production of anti-arachnid serum. Between 1993 and 2000, the laboratory received 24.781 specimens of Tityus serrulatus in order to obtain poison for the production of anti-scorpion serum. In the first extraction, performed by electrical stimulation, the animals gave an average quantity of 0.4 mg venom per specimen. Animal acquisition and involved professional safety are considered. In addition, the captivity, handling and feeding techniques are described, as well as the method and equipment used for venom extraction. It shows the importance of regular campaigns, offering information to the general population in order to motivate these to catch and send alive scorpions to the Institute to assuring a regular entrance of scorpions.

  10. Evidencias morfológicas y moleculares que validan como especie a Centruroides tecomanus (Scorpiones, Buthidae Morphological and molecular evidence supporting specific status for Centruroides tecomanus (Scorpiones, Buthidae

    Directory of Open Access Journals (Sweden)

    Javier Ponce-Saavedra

    2009-04-01

    Full Text Available Se presentan evidencias morfológicas y moleculares para reconocer a Centruroides limpidus tecomanus Hoffmann (Scorpiones: Buthidae como especie válida y no como una subespecie de Centruroides limpidus (Karsch. Se diagnostica la especie.Morphological and molecular evidence are provided to recognize Centruroides limpidus tecomanus Hoffmann (Scorpiones: Buthidae, as a valid species rather than a subspecies of Centruroides limpidus (Karsch. A diagnosis is provided.

  11. Serrumab: a novel human single chain-fragment antibody with multiple scorpion toxin-neutralizing capacities.

    Science.gov (United States)

    Pucca, Manuela Berto; Cerni, Felipe Augusto; Peigneur, Steve; Arantes, Eliane Candiani; Tytgat, Jan; Barbosa, José Elpidio

    2014-01-01

    In Brazil, scorpion envenomation is an important public health problem. The yellow scorpion, Tityus serrulatus (Ts), is considered the most dangerous species in the country, being responsible for the most severe clinical cases of envenomation. Currently, the administration of serum produced in horses is recognized and used as a treatment for accidents with scorpions. However, horse herds' maintenance is costly and the antibodies are heterologous, which can cause anaphylaxis and Serum Sickness. In the present work, a human monoclonal fragment antibody, Serrumab, has been analysed. Toxin neutralizing effects of Serrumab were evaluated using a two-electrode voltage-clamp technique. The results show that Serrumab presented a high neutralizing effect against Ts β-toxins (Ts1, 43.2% and Ts2, 68.8%) and none or low neutralizing effect against α-toxins (Ts3, 0% and Ts5, 10%). Additional experiments demonstrated that Serrumab was also able to neutralize the action of toxins from other scorpion genus (Css II, 45.96% and Lqh III, 100%/β- and α-toxins, respectively). This work indicated that Serrumab is able to neutralize many toxins in Ts venom, and could being considered as a neutralizing antibody for formulating a human anti-scorpion serum in Brazil. Additionally, this work demonstrated that Serrumab could neutralize different toxins from distinct scorpion genus. All these results reinforce the idea that Serrumab is a scFv antibody with multiple neutralizing capacities and a promising candidate for inclusion in scorpion anti-venoms against different genera.

  12. Camelid antivenom development and potential in vivo neutralization of Hottentotta saulcyi scorpion venom.

    Science.gov (United States)

    Darvish, Maryam; Ebrahimi, Soltan Ahmad; Shahbazzadeh, Delavar; Bagheri, Kamran-Pooshang; Behdani, Mahdi; Shokrgozar, Mohammad Ali

    2016-04-01

    Scorpion envenoming is a serious health problem which can cause a variety of clinical toxic effects. Of the many scorpion species native to Iran, Hottentotta saulcyi is important because its venom can produce toxic effects in man. Nowadays, antivenom derived from hyper immune horses is the only effective treatment for sever scorpion stings. Current limitations of immunotherapy urgently require an efficient alternative with high safety, target affinity and more promising venom neutralizing capability. Recently, heavy chain-only antibodies (HC-Abs) found naturally in camelid serum met the above mentioned advantages. In this study, immuno-reactivities of polyclonal antibodies were tested after successful immunization of camel using H. saulcyi scorpion crude venom. The lethal potency of scorpion venom in C57BL/6 mice injected intraperitoneally was determined to be 2.7 mg/kg. These results were followed by the efficient neutralization of lethal activity of H. saulcyi scorpion venom by injection of antivenom and purified IgG fractions into mice intraperitonelly or intravenously, respectively. HC-Ab camelid antivenom could be considered as a useful serotherapeutics instead of present treatment for scorpion envenomation.

  13. Scorpion Toxin, BmP01, Induces Pain by Targeting TRPV1 Channel.

    Science.gov (United States)

    Hakim, Md Abdul; Jiang, Wenbin; Luo, Lei; Li, Bowen; Yang, Shilong; Song, Yuzhu; Lai, Ren

    2015-09-14

    The intense pain induced by scorpion sting is a frequent clinical manifestation. To date, there is no established protocol with significant efficacy to alleviate the pain induced by scorpion envenomation. One of the important reasons is that, little information on pain-inducing compound from scorpion venoms is available. Here, a pain-inducing peptide (BmP01) has been identified and characterized from the venoms of scorpion (Mesobuthus martensii). In an animal model, intraplantar injection of BmP01 in mouse hind paw showed significant acute pain in wild type (WT) mice but not in TRPV1 knock-out (TRPV1 KO) mice during 30 min recording. BmP01 evoked currents in WT dorsal root ganglion (DRG) neurons but had no effect on DRG neurons of TRPV1 KO mice. Furthermore, OPEN ACCESS Toxins 2015, 7 3672 BmP01 evoked currents on TRPV1-expressed HEK293T cells, but not on HEK293T cells without TRPV1. These results suggest that (1) BmP01 is one of the pain-inducing agents in scorpion venoms; and (2) BmP01 induces pain by acting on TRPV1. To our knowledge, this is the first report about a scorpion toxin that produces pain by targeting TRPV1. Identification of a pain-inducing compound may facilitate treating pain induced by scorpion envenomation.

  14. Epidemiological survey on scorpionism in Gotvand County, Southwestern Iran:an analysis of 1 067 patients

    Institute of Scientific and Technical Information of China (English)

    Hamid Kassiri; Elnaz Kassiri; Rahele Veys-Behbahani; Ali Kassiri

    2014-01-01

    Objective:To study epidemiologic parameters of scorpion stings inGotvandCounty, SouthwesternIran, during2006-2008.Methods:In this descriptive study, data were collected from health services center's files atGotvandCounty.A special scorpion sting sheet was prepared.This sheet contained information about the site of scorpion stung, the date and place of the accident, the sex of the injured and etc.The frequencies of entomo-epidemiological characters were changed to the percentage basis.Results:Cases were collected from health services center's files over three years.There were1067 scorpion victims,44.1% of whom were from rural areas.Stings occurred throughout the year, however, the highest and lowest frequency happened inAugust(12.5%),January(1.9%) andFebruary(1.9%), respectively.About41.9% of stings were on the feet and38.8% on the hands.Stings mainly occurred in summer(35.3%) and spring(33.2%), respectively.The average of prevalence rate of scorpion sting in the county was 5.6/1000 people.The scorpions responsible for the majority of stings were identified as67.3% yellow,20.2% black and12.5% unknown colors. Conclusions:Scorpionism inGotvandCounty ofKhuzestanProvince is a public health problem, which needs to be monitored carefully by the government.

  15. Modelling the scorpion stings using surveillance data in El Bayadh Province, Algeria

    Directory of Open Access Journals (Sweden)

    Schehrazad Selmane

    2016-12-01

    Full Text Available Objective: To examine some epidemiological features of scorpion envenomations, analyse and interpret the recorded data, find any relationship between the incidence of scorpion stings and climatic factors, and finally develop a statistical model to estimate the variability among future cases in El Bayadh Province, Algeria. Methods: To assess the effects of climate variability on the scorpion envenomations, we applied the count data regression models to the monthly recorded scorpion stings in El Bayadh Province from 2001 to 2012. Results: The epidemiological analysis of data revealed that scorpion stings occured mainly in rural areas, round the clock, all year long with the highest seasonal incidence in summer, and the lowest in winter, all ages with male predominance. The ends of upper and lower limbs were the most affected parts of the human body. The majority of cases (95.7% were classified as mild envenomations and systemic toxicity was observed in 4.3% of cases. The use of count data regression models showed that the negative binomial regression was appropriate to forecast cases and the fitted data agreed considerably with the actual data. Moreover, the model had predicted the monthly scorpion sting cases for the year of 2013, with satisfactory accuracy. Conclusions: This study shows an optimism for forecasting scorpion stings by modelling and calibration with surveillance data and climate information. This knowledge could help to contain any unusual situation and assist health decision-makers to strengthen the prevention and control measures and to be in a state of readiness.

  16. An epidemiological study on scorpion envenomation in the Zagora oases (Morocco)

    Institute of Scientific and Technical Information of China (English)

    MoulayAbdelmonaim El Hidan; Oulaid Touloun; Ali Boumezzough

    2015-01-01

    Objective: To determine epidemiological features of scorpion stings in the oases of Southern Morocco: Zagora Province. Methods: A three-year prospective descriptive survey was performed to obtain epidemiological data on scorpion stings, including information on epidemiological characteristics of patients stung, and gathered information on scorpion species distribution. The following information was recorded for each scorpion sting: demographics of stung patients (age, gender, geographical location), circumstances of the sting (location, time, date, activity at the time), and many traditional medical attention. A questionnaire was completed for every stung patient. Concomitantly with the epidemiological survey, a systematic sampling of scorpions based on observations and direct captures in situ was applied. Results: There were 50 cases of death among 1053 cases studied. Most cases of death were recorded among children (under 15 years) (64%). The average age of victims was (23.00 ± 15.36) years. The scorpion sting occurred in 34.37% of cases between 18:00 and 24:00, and it coincided with the warm period and particularly between June and September (70%). The stings were principally in hands and feet (897 cases, 85.71%). The majority of victims had chosen traditional remedies (69.61%), and only 22.79% had received modern treatment while 1.33% of cases did not receive any treatment. The scorpion species involved were yellow in 179 cases and black in 815 cases. In 59 cases the scorpion involved was not identified. Conclusions: Our data constitute a preliminary descriptive study and suggest that scorpion envenomation is an important problem in the studied area.

  17. Hemprich's long-eared bat (Otonycteris hemprichii) as a predator of scorpions: whispering echolocation, passive gleaning and prey selection.

    Science.gov (United States)

    Holderied, Marc; Korine, Carmi; Moritz, Thorsten

    2011-05-01

    Over 70% of the droppings of the gleaning bat Otonycteris hemprichii can contain scorpion fragments. Yet, some scorpions found in its desert habitat possess venom of the highest known toxicity, rendering them a very dangerous prey. In this study, we describe how O. hemprichii catches and handles scorpions, quantify its flight and echolocation behaviour in the field, investigate what sensory modality it uses to detect scorpions, and test whether it selects scorpions according to their size or toxicity. We confirmed that O. hemprichi is a whispering bat (approx. 80 dB peSPL) with short, multi-harmonic calls. In a flight room we also confirmed that O. hemprichii detects scorpions by their walking noises. Amplitudes of such noises were measured and they reach the flying bat at or below the level of echoes of the loess substrate. Bats dropped straight onto moving scorpions and were stung frequently even straight in their face. Stings did not change the bats' behaviour and caused no signs of poisoning. Scorpions were eaten including poison gland and stinger. Bats showed no preference neither for any of the scorpion species nor their size suggesting they are generalist predators with regard to scorpions.

  18. Structure-Activity Relationship of Chlorotoxin-Like Peptides

    Directory of Open Access Journals (Sweden)

    Syed Abid Ali

    2016-02-01

    Full Text Available Animal venom (e.g., scorpion is a rich source of various protein and peptide toxins with diverse physio-/pharmaco-logical activities, which generally exert their action via target-specific modulation of different ion channel functions. Scorpion venoms are among the most widely-known source of peptidyl neurotoxins used for callipering different ion channels, such as; Na+, K+, Ca+, Cl−, etc. A new peptide of the chlorotoxin family (i.e., Bs-Tx7 has been isolated, sequenced and synthesized from scorpion Buthus sindicus (family Buthidae venom. This peptide demonstrates 66% with chlorotoxin (ClTx and 82% with CFTR channel inhibitor (GaTx1 sequence identities reported from Leiurus quinquestriatus hebraeus venom. The toxin has a molecular mass of 3821 Da and possesses four intra-chain disulphide bonds. Amino acid sequence analysis of Bs-Tx7 revealed the presence of a scissile peptide bond (i.e., Gly-Ile for human MMP2, whose activity is increased in the case of tumour malignancy. The effect of hMMP2 on Bs-Tx7, or vice versa, observed using the FRET peptide substrate with methoxycoumarin (Mca/dinitrophenyl (Dnp as fluorophore/quencher, designed and synthesized to obtain the lowest Km value for this substrate, showed approximately a 60% increase in the activity of hMMP2 upon incubation of Bs-Tx7 with the enzyme at a micromolar concentration (4 µM, indicating the importance of this toxin in diseases associated with decreased MMP2 activity.

  19. A potent potassium channel blocker from Mesobuthus eupeus scorpion venom.

    Science.gov (United States)

    Gao, Bin; Peigneur, Steve; Tytgat, Jan; Zhu, Shunyi

    2010-12-01

    Scorpion venom-derived peptidyl toxins are valuable pharmacological tools for investigating the structure-function relationship of ion channels. Here, we report the purification, sequencing and functional characterization of a new K(+) channel blocker (MeuKTX) from the venom of the scorpion Mesobuthus eupeus. Effects of MeuKTX on ten cloned potassium channels in Xenopus oocytes were evaluated using two-electrode voltage-clamp recordings. MeuKTX is the orthologue of BmKTX (α-KTx3.6), a known Kv1.3 blocker from the scorpion Mesobuthus martensii, and classified as α-KTx3.13. MeuKTX potently blocks rKv1.1, rKv1.2 and hKv1.3 channels with 50% inhibitory concentration (IC(50)) of 203.15 ± 4.06 pM, 8.92 ± 2.3 nM and 171 ± 8.56 pM, respectively, but does not affect rKv1.4, rKv1.5, hKv3.1, rKv4.3, and hERG channels even at 2 μM concentration. At this high concentration, MeuKTX is also active on rKv1.6 and Shaker IR. Our results also demonstrate that MeuKTX and BmKTX have the same channel spectrum and similar pharmacological potency. Analysis of the structure-function relationships of α-KTx3 subfamily toxins allows us to recognize several key sites which may be useful for designing toxins with improved activity on hKv1.3, an attractive target for T-cell mediated autoimmune diseases.

  20. Transient Myocarditis and Cardiomyopathy After Scorpion and Spider Envenomation

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    Mustafa Kır

    2011-08-01

    Full Text Available Introduction: Spider and scorpion stings can cause multiple clinical manifestations such as local skin reactions or multiple organ failure that can cause death. Multi-organ involvement is more frequent in children due to their lower body weight. The most important life threatening event after the sting is cardiac and lung involvement. In this case report, two cases who developed myocarditis and cardiomyopathy following scorpion and spider stings were reported.Case Report: Clinical evaluation of a ten-year-old boy with respiratory distress and tachycardia after being bitten by a spider on his right hand revealed high levels of cardiac enzymes [CK-MB: 16.5 ng/ml (N:0.0-7.2 ng/ml, troponin: 3.06 ng/ml (N:0.0-0.3ng/ml], pathological ST elevations in leads V3 and V4, and T wave negativity in leads V5 and V6. In echocardiography, left ventricular dilatation and moderate systolic dysfunction were found. Antivenom [Serum antiscorpionique (labs 50] was given (5 cc antivenom was administered intravenously following a 1:10 dilution with normal saline. With supportive treatment, all pathological findings resolved in a week. The second case was an eight-year-old boy who had been bitten by a scorpion on his foot and taken to the intensive care unit because of respiratory distress and convulsion. Two doses of antivenom were given to the case who had elevated levels of troponin and CK-MB, pathological ST depressions in ECG, and left ventricular dilatation and systolic dysfunction, as revealed by echocardiography. With dobutamin and supportive treatment, the pathological findings normalized in ten days.Conclusion: Myocarditis developing following spider or scorpion bites can threaten life due to left ventricular systolic dysfunction. This consequence has been attributed to increased catecholaminergic activity or direct effect of toxin to myocardial fibres. ECG must be performed, cardiac enzymes must be monitored and echocardiography must be done to evaluate

  1. Genetic and morphological analyses indicate that the Australian endemic scorpion Urodacus yaschenkoi (Scorpiones: Urodacidae) is a species complex

    Science.gov (United States)

    Luna-Ramirez, Karen; Miller, Adam D.

    2017-01-01

    Background Australian scorpions have received far less attention from researchers than their overseas counterparts. Here we provide the first insight into the molecular variation and evolutionary history of the endemic Australian scorpion Urodacus yaschenkoi. Also known as the inland robust scorpion, it is widely distributed throughout arid zones of the continent and is emerging as a model organism in biomedical research due to the chemical nature of its venom. Methods We employed Bayesian Inference (BI) methods for the phylogenetic reconstructions and divergence dating among lineages, using unique haplotype sequences from two mitochondrial loci (COXI, 16S) and one nuclear locus (28S). We also implemented two DNA taxonomy approaches (GMYC and PTP/dPTP) to evaluate the presence of cryptic species. Linear Discriminant Analysis was used to test whether the linear combination of 21 variables (ratios of morphological measurements) can predict individual’s membership to a putative species. Results Genetic and morphological data suggest that U. yaschenkoi is a species complex. High statistical support for the monophyly of several divergent lineages was found both at the mitochondrial loci and at a nuclear locus. The extent of mitochondrial divergence between these lineages exceeds estimates of interspecific divergence reported for other scorpion groups. The GMYC model and the PTP/bPTP approach identified major lineages and several sub-lineages as putative species. Ratios of several traits that approximate body shape had a strong predictive power (83–100%) in discriminating two major molecular lineages. A time-calibrated phylogeny dates the early divergence at the onset of continental-wide aridification in late Miocene and Pliocene, with finer-scale phylogeographic patterns emerging during the Pleistocene. This structuring dynamics is congruent with the diversification history of other fauna of the Australian arid zones. Discussion Our results indicate that the

  2. Binding of beta-scorpion toxin: a physicochemical study.

    Science.gov (United States)

    Jover, E; Bablito, J; Couraud, F

    1984-03-13

    The binding to rat brain synaptosomes of a beta-scorpion toxin, i.e., toxin II of Centruroides suffusus suffusus (Css II), was studied as a function of pH, temperature, and concentration of some monovalent and divalent cations. At 10 degrees C and pH 6.0, the specific binding of 125I-labeled Css II corresponds to a single class of noninteracting high-affinity binding sites (KD = 0.18 nM) with a capacity (4.2 pmol/mg of protein) that is almost identical with that generally accepted for saxitoxin. The equilibrium dissociation constant of beta-scorpion toxin is pH independent, but the maximum binding capacity is reduced with increasing pH. Li+, guanidinium, Ca2+, Mg2+, and Mn2+ modified the apparent KD of the 125I-labeled Css II toxin. The equilibrium dissociation constant varies markedly with the temperature. The van't Hoff plot of the data is curvilinear, corresponding to a standard free-energy change associated with an entropy-driven process. The association rate constant also varies considerably with the temperature whereas the Arrhenius plot is linear between 1 and 30 degrees C. The energy of activation determined from these data is 17.6 kcal/mol. These results support the hypothesis that a cluster of nonpolar amino acid residues present on one face of the molecule is involved in the toxin-receptor interaction.

  3. Mesobuthus eupeus scorpionism in Sanliurfa region of Turkey

    Directory of Open Access Journals (Sweden)

    O. Ozkan

    2005-12-01

    Full Text Available The epidemiology and clinical findings of scorpion stings in Sanliurfa region of Turkey, from May to September 2003, were evaluated in this study. Mesobuthus eupeus (M. eupeus plays a role on 25.8% of the scorpionism cases. This study also showed that intoxications caused by M. eupeus in the southeast of Anatolia region were seen in hot months of the summer, especially on July. Females and people above 15 years old were mostly affected and stung on extremities. Intense pain in the affected area was observed in 98.7% cases, hyperemia in 88.8%, swelling in 54.6%, burning in 19.7%, while numbness and itching were seen less frequently. In our study, the six most frequently observed symptoms were local pain, hyperemia, swelling, burning, dry mouth, thirst, sweating, and hypotension. In this study involving 152 M. eupeus toxicity cases, patients showed local and systemic clinical effects but no death was seen. Autonomic system and local effects characterized by severe pain, hyperemia and edema were dominantly seen in toxicity cases.

  4. HP Velotochnik Scorpion fx卧式自行车

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    开上旅行车举家到远郊,支起帐篷,再骑上自行车穿梭于林间,这种休闲方式虽然有点守日,但是却总让人乐此不疲。好吧,现在让HP Velotochnik Scorpion fx式自行车再给你的休闲生活加点助鲜的“鸡精”!作为德国知名的卧式自行车生产厂商,HP Velotechnik所推出的Scorpion fx卧式自行车采用轻质高强度合金制成,总重不过17.1kg:三个轮子全部采用液压碟片式刹车,安全性很高:后悬采用的则是弹簧式减震器,并具备变速功能,充分应对复杂的山地环境路况。更为神奇的是,

  5. Chlorotoxin Fused to IgG-Fc Inhibits Glioblastoma Cell Motility via Receptor-Mediated Endocytosis

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    Tomonari Kasai

    2012-01-01

    Full Text Available Chlorotoxin is a 36-amino acid peptide derived from Leiurus quinquestriatus (scorpion venom, which has been shown to inhibit low-conductance chloride channels in colonic epithelial cells. Chlorotoxin also binds to matrix metalloproteinase-2 and other proteins on glioma cell surfaces. Glioma cells are considered to require the activation of matrix metalloproteinase-2 during invasion and migration. In this study, for targeting glioma, we designed two types of recombinant chlorotoxin fused to human IgG-Fcs with/without a hinge region. Chlorotoxin fused to IgG-Fcs was designed as a dimer of 60 kDa with a hinge region and a monomer of 30 kDa without a hinge region. The monomeric and dimeric forms of chlorotoxin inhibited cell proliferation at 300 nM and induced internalization in human glioma A172 cells. The monomer had a greater inhibitory effect than the dimer; therefore, monomeric chlorotoxin fused to IgG-Fc was multivalently displayed on the surface of bionanocapsules to develop a drug delivery system that targeted matrix metalloproteinase-2. The target-dependent internalization of bionanocapsules in A172 cells was observed when chlorotoxin was displayed on the bionanocapsules. This study indicates that chlorotoxin fused to IgG-Fcs could be useful for the active targeting of glioblastoma cells.

  6. Purification of charybdotoxine, a specific inhibitor of the high-conductance Ca/sup 2 +/-activated K/sup +/ channel

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.; Phillips, M.; Miller, C.

    1986-11-05

    Charybdotoxim is a high-affinity specific inhibitor of the high-conductance Ca/sup 2 +/-activated K/sup +/ channel found in the plasma membranes of many vertebrate cell types. Using Ca/sup 2 +/-activated K/sup +/ channels reconstituted into planar lipid bilayer membranes as an assay, the authors have purified the toxin from the venom of the scorpion Leiurus quinquestriatus by a two-step procedure involving chromatofocusing on SP-Sephadex, followed by reversed-phase high-performance liquid chromatography. Charybdotoxin is shown to be a highly basic protein with a mass of 10 kDa. Under the standard assay conditions, the purified toxin inhibits the Ca/sup 2 +/-activated K/sup +/ channel with an apparent dissociation constant of 3.5 nM. The protein is unusually stable, with inhibitory potency being insensitive to boiling or exposure to organic solvents. The toxin's activity is sensitive to chymotrypsin treatment and to acylation of lysine groups. The protein may be radioiodinated without loss of activity.

  7. Action of insecticidal N-alkylamides at site 2 of the voltage-sensitive sodium channel

    Energy Technology Data Exchange (ETDEWEB)

    Ottea, J.A.; Payne, G.T.; Soderlund, D.M. (Cornell Univ., Geneva, NY (USA))

    1990-08-01

    Nine synthetic N-alkylamides were examined as inhibitors of the specific binding of ({sup 3}H)batrachotoxinin A 20{alpha}-benzoate (({sup 3}H)BTX-B) to sodium channels and as activators of sodium uptake in mouse brain synaptoneurosomes. In the presence of scorpion (Leiurus quinquestriatus) venom, the six insecticidal analogues were active as both inhibitors of ({sup 3}H)BTX-B binding and stimulators of sodium uptake. These findings are consistent with an action of these compounds at the alkaloid activator recognition site (site 2) of the voltage-sensitive sodium channel. The three noninsecticidal N-alkylamides also inhibited ({sup 3}H)BTX-B binding but were ineffective as activators of sodium uptake. Concentration-response studies revealed that some of the insecticidal amides also enhanced sodium uptake through a second, high-affinity interaction that does not involve site 2, but this secondary effect does not appear to be correlated with insecticidal activity. The activities of N-alkylamides as sodium channel activators were influenced by the length of the alkenyl chain and the location of unsaturation within the molecule. These results further define the actions of N-alkylamides on sodium channels and illustrate the significance of the multiple binding domains of the sodium channel as target sites for insect control agents.

  8. Venom Gland Transcriptomic and Proteomic Analyses of the Enigmatic Scorpion Superstitionia donensis (Scorpiones: Superstitioniidae), with Insights on the Evolution of Its Venom Components

    Science.gov (United States)

    Santibáñez-López, Carlos E.; Cid-Uribe, Jimena I.; Batista, Cesar V. F.; Ortiz, Ernesto; Possani, Lourival D.

    2016-01-01

    Venom gland transcriptomic and proteomic analyses have improved our knowledge on the diversity of the heterogeneous components present in scorpion venoms. However, most of these studies have focused on species from the family Buthidae. To gain insights into the molecular diversity of the venom components of scorpions belonging to the family Superstitioniidae, one of the neglected scorpion families, we performed a transcriptomic and proteomic analyses for the species Superstitionia donensis. The total mRNA extracted from the venom glands of two specimens was subjected to massive sequencing by the Illumina protocol, and a total of 219,073 transcripts were generated. We annotated 135 transcripts putatively coding for peptides with identity to known venom components available from different protein databases. Fresh venom collected by electrostimulation was analyzed by LC-MS/MS allowing the identification of 26 distinct components with sequences matching counterparts from the transcriptomic analysis. In addition, the phylogenetic affinities of the found putative calcins, scorpines, La1-like peptides and potassium channel κ toxins were analyzed. The first three components are often reported as ubiquitous in the venom of different families of scorpions. Our results suggest that, at least calcins and scorpines, could be used as molecular markers in phylogenetic studies of scorpion venoms. PMID:27941686

  9. Cerebral edema associated to scorpion sting: a two-case sting report

    Directory of Open Access Journals (Sweden)

    N. O. Romero

    2005-12-01

    Full Text Available Scorpionism is a public health problem in some places in Mexico. The clinical symptoms of envenomation by scorpion sting are by sympathetic and parasympathetic stimulation, developing systemic and local symptoms. The Central Nervous System (CNS is one of the organs that are affected. In some cases, cerebral edema develops. In this report we present two pediatric cases with the association of envenomation by scorpion sting and cerebral edema. The first case developed severe cerebral edema, which progressed to a fatal outcome; and the other case developed mild cerebral edema with a satisfactory evolution. The pathophysiology of this complication is not well known and probably is the consequence of hypoxia, secondary to respiratory failure, laryngospasm and seizures that are manifestations of envenomation by scorpion sting.

  10. A new mid-Silurian aquatic scorpion-one step closer to land?

    Science.gov (United States)

    Waddington, Janet; Rudkin, David M; Dunlop, Jason A

    2015-01-01

    One of the oldest known fossil scorpions, a new species from the mid-Silurian Eramosa Formation (430 myr) of Ontario, Canada, exhibits several surprising features. The depositional environment and associated biota indicate a marine habitat; however, the leg morphology of this scorpion, which has a short tarsus in common with all Recent scorpions, suggests that a key adaptation for terrestrial locomotion, the ability to support its weight on a subterminal 'foot', appeared remarkably early in the scorpion fossil record. Specimens are preserved intact and undisturbed in a splayed posture typical of moults rather than carcasses. We postulate that these animals were aquatic, but occasionally ventured into extremely shallow water, or onto a transient subaerially exposed surface while moulting, before returning to deeper water. Shed exuviae were preserved in situ by rapid overgrowth of bacterial biofilm.

  11. Ecology of the Scorpion, Microtityus jaumei in Sierra de Canasta, Cuba

    Science.gov (United States)

    Cala-Riquelme, Franklyn; Colombo, Marco

    2011-01-01

    An assessment of the population dynamics of Microtityus jaumei Armas (Scorpiones: Buthidae) on the slopes south of Sierra de Canasta, Guantánamo Province, Cuba show an increase in activity over the year (≤ 0.05). The activity peak is related to the reproductive period from June to November. The abundance of scorpions was significantly related to density of the canopy and thickness of the substrate. PMID:21870972

  12. Neutralizing Effects of Mimosa tenuiflora Extracts against Inflammation Caused by Tityus serrulatus Scorpion Venom

    OpenAIRE

    Mariana Angélica Oliveira Bitencourt; Maira Conceição Jerônimo de Souza Lima; Manoela Torres-Rêgo; Júlia Morais Fernandes; Arnóbio Antônio da Silva-Júnior; Denise Vilarinho Tambourgi; Silvana Maria Zucolotto; Matheus de Freitas Fernandes-Pedrosa

    2014-01-01

    Scorpion bite represents a significant and serious public health problem in certain regions of Brazil, as well as in other parts of the world. Inflammatory mediators are thought to be involved in the systemic and local immune response induced by Tityus serrulatus scorpion envenomation. The aim of this study was to evaluate the effect of extracts of Mimosa tenuiflora on model envenomation. In mice, the envenomation model is induced by Tityus serrulatus venom. Previous treatment of mice with fr...

  13. Notes and observations on courtship and mating in Tityus (Atreus magnimanus Pocock, 1897 (Scorpiones: Buthidae

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    LK Ross

    2009-01-01

    Full Text Available Courtship and mating behaviors of the scorpion Tityus (Atreus magnimanus are herein described, consisting of various components that pertain to four distinct behavioral stages. The courtship and mating rituals of Tityus (Atreus magnimanus are similar to those of other scorpions. Behavioral components are presented in an ethogram to demonstrate their occurrence during mating sequences. The current report is presented as observational data that were acquired during life history studies of this species.

  14. Comparative venom gland transcriptome analysis of the scorpion Lychas mucronatus reveals intraspecific toxic gene diversity and new venomous components.

    Science.gov (United States)

    Ruiming, Zhao; Yibao, Ma; Yawen, He; Zhiyong, Di; Yingliang, Wu; Zhijian, Cao; Wenxin, Li

    2010-07-28

    Lychas mucronatus is one scorpion species widely distributed in Southeast Asia and southern China. Anything is hardly known about its venom components, despite the fact that it can often cause human accidents. In this work, we performed a venomous gland transcriptome analysis by constructing and screening the venom gland cDNA library of the scorpion Lychas mucronatus from Yunnan province and compared it with the previous results of Hainan-sourced Lychas mucronatus. A total of sixteen known types of venom peptides and proteins are obtained from the venom gland cDNA library of Yunnan-sourced Lychas mucronatus, which greatly increase the number of currently reported scorpion venom peptides. Interestingly, we also identified nineteen atypical types of venom molecules seldom reported in scorpion species. Surprisingly, the comparative transcriptome analysis of Yunnan-sourced Lychas mucronatus and Hainan-sourced Lychas mucronatus indicated that enormous diversity and vastly abundant difference could be found in venom peptides and proteins between populations of the scorpion Lychas mucronatus from different geographical regions. This work characterizes a large number of venom molecules never identified in scorpion species. This result provides a comparative analysis of venom transcriptomes of the scorpion Lychas mucronatus from different geographical regions, which thoroughly reveals the fact that the venom peptides and proteins of the same scorpion species from different geographical regions are highly diversified and scorpion evolves to adapt a new environment by altering the primary structure and abundance of venom peptides and proteins.

  15. Comparative venom gland transcriptome analysis of the scorpion Lychas mucronatus reveals intraspecific toxic gene diversity and new venomous components

    Directory of Open Access Journals (Sweden)

    Zhijian Cao

    2010-07-01

    Full Text Available Abstract Background Lychas mucronatus is one scorpion species widely distributed in Southeast Asia and southern China. Anything is hardly known about its venom components, despite the fact that it can often cause human accidents. In this work, we performed a venomous gland transcriptome analysis by constructing and screening the venom gland cDNA library of the scorpion Lychas mucronatus from Yunnan province and compared it with the previous results of Hainan-sourced Lychas mucronatus. Results A total of sixteen known types of venom peptides and proteins are obtained from the venom gland cDNA library of Yunnan-sourced Lychas mucronatus, which greatly increase the number of currently reported scorpion venom peptides. Interestingly, we also identified nineteen atypical types of venom molecules seldom reported in scorpion species. Surprisingly, the comparative transcriptome analysis of Yunnan-sourced Lychas mucronatus and Hainan-sourced Lychas mucronatus indicated that enormous diversity and vastly abundant difference could be found in venom peptides and proteins between populations of the scorpion Lychas mucronatus from different geographical regions. Conclusions This work characterizes a large number of venom molecules never identified in scorpion species. This result provides a comparative analysis of venom transcriptomes of the scorpion Lychas mucronatus from different geographical regions, which thoroughly reveals the fact that the venom peptides and proteins of the same scorpion species from different geographical regions are highly diversified and scorpion evolves to adapt a new environment by altering the primary structure and abundance of venom peptides and proteins.

  16. Broadening the neutralizing capacity of a family of antibody fragments against different toxins from Mexican scorpions.

    Science.gov (United States)

    Rodríguez-Rodríguez, Everardo Remi; Olamendi-Portugal, Timoteo; Serrano-Posada, Hugo; Arredondo-López, Jonathan Noé; Gómez-Ramírez, Ilse; Fernández-Taboada, Guillermo; Possani, Lourival D; Anguiano-Vega, Gerardo Alfonso; Riaño-Umbarila, Lidia; Becerril, Baltazar

    2016-09-01

    New approaches aimed at neutralizing the primary toxic components present in scorpion venoms, represent a promising alternative to the use of antivenoms of equine origin in humans. New potential therapeutics developed by these approaches correspond to neutralizing antibody fragments obtained by selection and maturation processes from libraries of human origin. The high sequence identity shared among scorpion toxins is associated with an important level of cross reactivity exhibited by these antibody fragments. We have exploited the cross reactivity showed by single chain variable antibody fragments (scFvs) of human origin to re-direct the neutralizing capacity toward various other scorpion toxins. As expected, during these evolving processes several variants derived from a parental scFv exhibited the capacity to simultaneously recognize and neutralize different toxins from Centruroides scorpion venoms. A sequence analyses of the cross reacting scFvs revealed that specific mutations are responsible for broadening their neutralizing capacity. In this work, we generated a set of new scFvs that resulted from the combinatorial insertion of these point mutations. These scFvs are potential candidates to be part of a novel recombinant antivenom of human origin that could confer protection against scorpion stings. A remarkable property of one of these new scFvs (ER-5) is its capacity to neutralize at least three different toxins and its complementary capacity to neutralize the whole venom from Centruroides suffusus in combination with a second scFv (LR), which binds to a different epitope shared by Centruroides scorpion toxins.

  17. Protease inhibitor in scorpion (Mesobuthus eupeus) venom prolongs the biological activities of the crude venom.

    Science.gov (United States)

    Ma, Hakim; Xiao-Peng, Tang; Yang, Shi-Long; Lu, Qiu-Min; Lai, Ren

    2016-08-01

    It is hypothesized that protease inhibitors play an essential role in survival of venomous animals through protecting peptide/protein toxins from degradation by proteases in their prey or predators. However, the biological function of protease inhibitors in scorpion venoms remains unknown. In the present study, a trypsin inhibitor was purified and characterized from the venom of scorpion Mesobuthus eupeus, which enhanced the biological activities of crude venom components in mice when injected in combination with crude venom. This protease inhibitor, named MeKTT-1, belonged to Kunitz-type toxins subfamily. Native MeKTT-1 selectively inhibited trypsin with a Kivalue of 130 nmol·L(-1). Furthermore, MeKTT-1 was shown to be a thermo-stable peptide. In animal behavioral tests, MeKTT-1 prolonged the pain behavior induced by scorpion crude venom, suggesting that protease inhibitors in scorpion venom inhibited proteases and protect the functionally important peptide/protein toxins from degradation, consequently keeping them active longer. In conclusion, this was the first experimental evidence about the natural existence of serine protease inhibitor in the venom of scorpion Mesobuthus eupeus, which preserved the activity of venom components, suggests that scorpions may use protease inhibitors for survival. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  18. Severity of Scorpion Stings in the Western Brazilian Amazon: A Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Amanda M Queiroz

    Full Text Available Scorpion stings are a major public health problem in Brazil, with an increasing number of registered cases every year. Affecting mostly vulnerable populations, the phenomenon is not well described and is considered a neglected disease. In Brazil, the use of anti-venom formulations is provided free of charge. The associate scorpion sting case is subject to compulsory reporting. This paper describes the epidemiology and identifies factors associated with severity of scorpions stings in the state of Amazonas, in the Western Brazilian Amazon.This study included all cases of scorpion stings in the state of Amazonas reported to the Brazilian Diseases Surveillance System from January 1, 2007 to December 31, 2014. A case-control study was conducted to identify factors associated with scorpions sting severity. A total of 2,120 cases were reported during this period. The mean incidence rate in the Amazonas was 7.6 per 100,000 inhabitants/year. Scorpion stings showed a large spatial distribution in the state and represent a potential occupational health problem for rural populations. There was a positive correlation between the absolute number of cases and the altimetric river levels in the Central (p<0.001; Rs = 0.479 linear and Southwest (p = 0.032; linear Rs = 0.261 regions of the state. Cases were mostly classified as mild (68.6%, followed by moderate (26.8%, and severe (4.6%. The overall lethality rate was 0.3%. Lethality rate among children ≤10 years was 1.3%. Age <10 years [OR = 2.58 (95%CI = 1.47-4.55; p = 0.001], stings occurring in the rural area [OR = 1.97 (95%CI = 1.18-3.29; p = 0.033 and in the South region of the state [OR = 1.85 (95%CI = 1.17-2.93; p = 0.008] were independently associated with the risk of developing severity.Scorpion stings show an extensive distribution in the Western Brazilian Amazon threatening especially rural populations, children ≤10 in particular. Thus, the mapping of scorpions fauna in different Amazon localities

  19. Severity of Scorpion Stings in the Western Brazilian Amazon: A Case-Control Study

    Science.gov (United States)

    Queiroz, Amanda M.; Sampaio, Vanderson S.; Mendonça, Iran; Fé, Nelson F.; Sachett, Jacqueline; Ferreira, Luiz Carlos L.; Feitosa, Esaú; Wen, Fan Hui; Lacerda, Marcus; Monteiro, Wuelton

    2015-01-01

    Background Scorpion stings are a major public health problem in Brazil, with an increasing number of registered cases every year. Affecting mostly vulnerable populations, the phenomenon is not well described and is considered a neglected disease. In Brazil, the use of anti-venom formulations is provided free of charge. The associate scorpion sting case is subject to compulsory reporting. This paper describes the epidemiology and identifies factors associated with severity of scorpions stings in the state of Amazonas, in the Western Brazilian Amazon. Methodology/Principal Findings This study included all cases of scorpion stings in the state of Amazonas reported to the Brazilian Diseases Surveillance System from January 1, 2007 to December 31, 2014. A case-control study was conducted to identify factors associated with scorpions sting severity. A total of 2,120 cases were reported during this period. The mean incidence rate in the Amazonas was 7.6 per 100,000 inhabitants/year. Scorpion stings showed a large spatial distribution in the state and represent a potential occupational health problem for rural populations. There was a positive correlation between the absolute number of cases and the altimetric river levels in the Central (p<0.001; Rs = 0.479 linear) and Southwest (p = 0.032; linear Rs = 0.261) regions of the state. Cases were mostly classified as mild (68.6%), followed by moderate (26.8%), and severe (4.6%). The overall lethality rate was 0.3%. Lethality rate among children ≤10 years was 1.3%. Age <10 years [OR = 2.58 (95%CI = 1.47–4.55; p = 0.001)], stings occurring in the rural area [OR = 1.97 (95%CI = 1.18–3.29; p = 0.033) and in the South region of the state [OR = 1.85 (95%CI = 1.17–2.93; p = 0.008)] were independently associated with the risk of developing severity. Conclusions/Significance Scorpion stings show an extensive distribution in the Western Brazilian Amazon threatening especially rural populations, children ≤10 in particular. Thus

  20. Evolution stings: the origin and diversification of scorpion toxin peptide scaffolds.

    Science.gov (United States)

    Sunagar, Kartik; Undheim, Eivind A B; Chan, Angelo H C; Koludarov, Ivan; Muñoz-Gómez, Sergio A; Antunes, Agostinho; Fry, Bryan G

    2013-12-13

    The episodic nature of natural selection and the accumulation of extreme sequence divergence in venom-encoding genes over long periods of evolutionary time can obscure the signature of positive Darwinian selection. Recognition of the true biocomplexity is further hampered by the limited taxon selection, with easy to obtain or medically important species typically being the subject of intense venom research, relative to the actual taxonomical diversity in nature. This holds true for scorpions, which are one of the most ancient terrestrial venomous animal lineages. The family Buthidae that includes all the medically significant species has been intensely investigated around the globe, while almost completely ignoring the remaining non-buthid families. Australian scorpion lineages, for instance, have been completely neglected, with only a single scorpion species (Urodacus yaschenkoi) having its venom transcriptome sequenced. Hence, the lack of venom composition and toxin sequence information from an entire continent's worth of scorpions has impeded our understanding of the molecular evolution of scorpion venom. The molecular origin, phylogenetic relationships and evolutionary histories of most scorpion toxin scaffolds remain enigmatic. In this study, we have sequenced venom gland transcriptomes of a wide taxonomical diversity of scorpions from Australia, including buthid and non-buthid representatives. Using state-of-art molecular evolutionary analyses, we show that a majority of CSα/β toxin scaffolds have experienced episodic influence of positive selection, while most non-CSα/β linear toxins evolve under the extreme influence of negative selection. For the first time, we have unraveled the molecular origin of the major scorpion toxin scaffolds, such as scorpion venom single von Willebrand factor C-domain peptides (SV-SVC), inhibitor cystine knot (ICK), disulphide-directed beta-hairpin (DDH), bradykinin potentiating peptides (BPP), linear non-disulphide bridged

  1. Two bioactive compounds from the Chinese scorpion Buthusmartensii Karsch.

    Science.gov (United States)

    Gao, Jiayu; Yin, Weiping; Gao, Ting; Deng, Ruixue; Li, Xin

    2014-01-01

    Two compounds, 3β-acetoxyl,2,14,22-trihydroxy,19-hydroxymethyl,9α,5β,14β-card-20(22)enolide (1) and 1,2,3,4-tetrahydro-6-hydroxy1-5-pyrimidinecarbox-aldehyde (2), were isolated from arthropods in scorpion, Buthus martensii Karsch, by medium pressure liquid chromatography with silica gel as stationary phase and RP-HPLC analysis technology. The structures were elucidated on the basis of NMR spectroscopic analysis and HR-ESI-MS determination. It was found that (1) is a novel compound and both compounds showed inhibitory activities against the Gram-positive bacteria Bacillus subtilis (minimum inhibitory concentrations = 15 μg/mL), with diameter of inhibition zone at ϕ = 6.0 mm (compound 1) and ϕ = 9.0 mm (compound 2), respectively.

  2. A Re-appraisal of the Rock Scorpions (Scorpionidae: Hadogenes

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    G. Newlands

    1985-12-01

    Full Text Available The morphological similarity between species of the rock scorpion genus Hadogenes has given rise to a great deal of controversy amongst taxonomists over the last eighty years. To resolve these difficulties, species of the genus were re-appraised in terms of their chromosome number and an electrophoretic analysis of venom proteins. The relationships arising from these data were integrated with morphological characteristics in order to get a more realistic appreciation of the genus. It emerges that the genus consists of 14 recognised species, some of which represent as yet unnamed species complexes. Taxonomic changes proposed are H. lawrencei sp. res., H. zuluanus stat. nov, H. gracilis fluvianus and H. gracilis namaquensis = H. phyllodes syn. n. A new key to the species is provided.

  3. Reliable Refuge: Two Sky Island Scorpion Species Select Larger, Thermally Stable Retreat Sites.

    Science.gov (United States)

    Becker, Jamie E; Brown, Christopher A

    2016-01-01

    Sky island scorpions shelter under rocks and other surface debris, but, as with other scorpions, it is unclear whether these species select retreat sites randomly. Furthermore, little is known about the thermal preferences of scorpions, and no research has been done to identify whether reproductive condition might influence retreat site selection. The objectives were to (1) identify physical or thermal characteristics for retreat sites occupied by two sky island scorpions (Vaejovis cashi Graham 2007 and V. electrum Hughes 2011) and those not occupied; (2) determine whether retreat site selection differs between the two study species; and (3) identify whether thermal selection differs between species and between gravid and non-gravid females of the same species. Within each scorpion's habitat, maximum dimensions of rocks along a transect line were measured and compared to occupied rocks to determine whether retreat site selection occurred randomly. Temperature loggers were placed under a subset of occupied and unoccupied rocks for 48 hours to compare the thermal characteristics of these rocks. Thermal gradient trials were conducted before parturition and after dispersal of young in order to identify whether gravidity influences thermal preference. Vaejovis cashi and V. electrum both selected larger retreat sites that had more stable thermal profiles. Neither species appeared to have thermal preferences influenced by reproductive condition. However, while thermal selection did not differ among non-gravid individuals, gravid V. electrum selected warmer temperatures than its gravid congener. Sky island scorpions appear to select large retreat sites to maintain thermal stability, although biotic factors (e.g., competition) could also be involved in this choice. Future studies should focus on identifying the various biotic or abiotic factors that could influence retreat site selection in scorpions, as well as determining whether reproductive condition affects thermal

  4. 1-D and 2-D electrophoresis protein profiles of the scorpion venom from Brotheas amazonicus

    Energy Technology Data Exchange (ETDEWEB)

    Higa, A.M.; Noronha, M.D.N. [Universidade do Estado do Amazonas (UEA), Manaus, AM (Brazil). Rede Proteomica do Amazonas (Proteam). Lab. de Genomica e Proteomica; Rocha-Oliveira, F.; Lopez-Lozano, J.L.L. [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Pos-Graduacao em Biotecnologia

    2008-07-01

    Full text: Introduction: Scorpions venoms show specific neurotoxins to insect or mammals. These toxins are very important molecular tools to development of news drugs or bioinsecticides. Brotheas amazonicus scorpion is an endemic specie in Amazonian Rain Forest, but your venom do not show toxicity in humans. Information about biological specific activity on insect of this venom is not known yet. Objectives: Molecular protein toxins profiles of the venom from Brotheas amazonicus scorpion by 1-D and 2-D electrophoresis methods to detected toxins with potential biotech applications. Results: Several spots 'families' with {approx} 60, 70 and 80 kDa were detected in gel acidic region with pI {approx} 4,5 - 6 range, in the same region 1-D zimography showed proteolytic activity on gelatin and fibrinogen and proteolytic activity was inhibited by PMSF, suggesting scorpion serine proteinases. 50 kDa proteins were detected with pI {approx} 6,5 - 7 range. In 23 - 50 kDa gel acid region were observed some proteins. In 23 - 14 kDa gel acidic region were detected proteins with pI 4 - 7 range. 1-D Tris-tricine gel showed proteins with {approx} 7 kDa, suggesting scorpion neurotoxins. In gel basic region only 14 kDa proteins were observed with pI {approx} 9 - 10 range. Conclusion: Molecular profile of the scorpion venom from B. amazonicus showed proteins with high and low molecular masses, mainly with acidic pI. Proteolytic activity suggest serine proteinases with high molecular masses and 7 kDa proteins in B. amazonicus venom suggest scorpion neurotoxins. Purification and molecular characterization of these toxins are in course.

  5. Scorpion Potassium Channel-blocking Defensin Highlights a Functional Link with Neurotoxin.

    Science.gov (United States)

    Meng, Lanxia; Xie, Zili; Zhang, Qian; Li, Yang; Yang, Fan; Chen, Zongyun; Li, Wenxin; Cao, Zhijian; Wu, Yingliang

    2016-03-25

    The structural similarity between defensins and scorpion neurotoxins suggests that they might have evolved from a common ancestor. However, there is no direct experimental evidence demonstrating a functional link between scorpion neurotoxins and defensins. The scorpion defensin BmKDfsin4 from Mesobuthus martensiiKarsch contains 37 amino acid residues and a conserved cystine-stabilized α/β structural fold. The recombinant BmKDfsin4, a classical defensin, has been found to have inhibitory activity against Gram-positive bacteria such as Staphylococcus aureus, Bacillus subtilis, and Micrococcus luteusas well as methicillin-resistant Staphylococcus aureus Interestingly, electrophysiological experiments showed that BmKDfsin4,like scorpion potassium channel neurotoxins, could effectively inhibit Kv1.1, Kv1.2, and Kv1.3 channel currents, and its IC50value for the Kv1.3 channel was 510.2 nm Similar to the structure-function relationships of classical scorpion potassium channel-blocking toxins, basic residues (Lys-13 and Arg-19) of BmKDfsin4 play critical roles in peptide-Kv1.3 channel interactions. Furthermore, mutagenesis and electrophysiological experiments demonstrated that the channel extracellular pore region is the binding site of BmKDfsin4, indicating that BmKDfsin4 adopts the same mechanism for blocking potassium channel currents as classical scorpion toxins. Taken together, our work identifies scorpion BmKDfsin4 as the first invertebrate defensin to block potassium channels. These findings not only demonstrate that defensins from invertebrate animals are a novel type of potassium channel blockers but also provide evidence of a functional link between defensins and neurotoxins.

  6. Escorpionismo por Tityus pusillus Pocock, 1893 (Scorpiones; Buthidae no Estado de Pernambuco Scorpionism caused by Tityus pusillus Pocock, 1893 (Scorpiones; Buthidae in State of Pernambuco

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    Cleide Maria Ribeiro de Albuquerque

    2009-04-01

    Full Text Available Apresentamos neste trabalho os primeiros relatos de acidente escorpiônico causado pela espécie Tityus pusillus (Buthidae. Os acidentes ocorreram no ambiente doméstico, na área rural situada nas cidades de Paudalho e São Lourenço da Mata, Pernambuco, Brasil. Os dois casos descritos, uma criança e uma mulher grávida, foram classificados como leve e moderado, respectivamente. Os sintomas clínicos apresentados foram distúrbios locais (dor e parestesia e distúrbios sistêmicos (calafrios, tontura, cefaléia e vômito. Esses registros permitem incluir Tityus pusillus como uma espécie de importância médica no Brasil.This paper presents the first reports on scorpion accidents caused by Tityus pusillus (Buthidae. The accidents took place within the home environment, in rural areas located in the municipalities of Paudalho and São Lourenço da Mata, Pernambuco, Brazil. The two cases described (a child and a pregnant woman were classified as mild and moderate, respectively. The clinical symptoms presented were local disorders (pain and paresthesia and systemic disorders (chills, dizziness, headache and vomiting. These records make it possible to including Tityus pusillus as a species of medical importance in Brazil.

  7. Precursors of Androctonus australis Scorpion Neurotoxins. Structures of Precursors, Processing Outcomes, and Expression of a Functional Recombinant Toxin II

    Science.gov (United States)

    1989-05-24

    Special got 31l The Buthid scorpion venoms are known to contain single-chain, basic proteins of 60 to 70 amino acid residues (1,2), tightly reticulated ... cellulose chromatography (18). The intactness of scorpion poly (A) + RNA and its ability to serve as template for full-length cDNA transcription was

  8. Spatial distribution of scorpions according to the socioeconomic conditions in Campina Grande,State of Paraíba, Brazil

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    Thassiany Sarmento Oliveira de Almeida

    Full Text Available Abstract: INTRODUCTION: Due to its frequency and morbidity, such as that caused by scorpions have achieved public health importance in certain regions of the world. The present exploratory ecological study aimed to characterize the epidemiological profile and spatial distribution of scorpion stings in Campina Grande, State of Paraíba in Northeastern Brazil. METHODS: Geographical information system techniques were used to record the scorpion stings, and Google Earth software, Track Maker, and ArcGIS 10 Esri were used as geocoding databases. The Moran test was used to evaluate spatial correlation, and the Pearson chi-square test was used to analyze associations between scorpion stings and socioeconomic variables. RESULTS: The study evaluated 1,466 scorpion stings. Envenomations were more frequent among women (n = 908, 61.9%, and most patients were aged 13-28 years (n = 428, 29.2%. The Southern region of the city had the largest number of registered cases (n = 548, 37.4%, followed by the Western region (n = 510, 34.8%. CONCLUSIONS: Spatial analysis of scorpionism revealed an irregular occurrence in Campina Grande. Further, no association was observed between the socioeconomic factors analyzed and the geographic location of the scorpion envenomations. Detection of spatial areas with an increased risk of scorpionism can help prioritize adoption of preventive measures in these regions to reduce the associated incidence and morbidity.

  9. Description of a new species of scorpion of the genus Lychas C.L. Koch, 1845 (Scorpiones: Buthidae from Maharashtra, India

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    Z.A. Mirza

    2010-04-01

    Full Text Available A new species of buthid scorpion belonging to the genus Lychas C.L. Koch, 1845 is described from the degraded scrub of Aarey Milk Colony (Mumbai. Lychas aareyensis sp. nov. is similar to L. nigristernis, but can be differentiated based on a combination of morphological characters. Notes on natural history are also presented.

  10. Scorpion poisoning in the Acosta and Caripe Counties of Monagas State, Venezuela. part 1: characterization of some epidemiological aspects.

    Science.gov (United States)

    De Sousa L; Parrilla; Tillero; Valdiviezo; Ledezma; Jorquera; Quiroga

    1997-01-01

    Scorpion poisoning was surveyed in Acosta and Caripe counties, located in the Turimiquire subregion of Monagas State, Venezuela, aiming to expand information on stings by characterizing some epidemiological aspects. From 1987 to 1993, 298 cases of scorpion stings were recorded in Acosta and Caripe counties. Acosta had 212 cases, with an annual incidence rate of 18.3 (cases per 10,000 inhabitants) and a period median incidence rate of 128 . The scorpion poisoning index is 4.18 times greater in Acosta than in Caripe, confirming the former as a hyperendemic zone for this type of injury, with a phenomenon of cyclical temporal fluctuations and an upward trend. This area is infested with scorpions of the genus Tityus. Our results show that the region surveyed in Monagas State is endemic for scorpion stings, posing a major public health problem.

  11. Scorpion poisoning in the Acosta and Caripe Counties of Monagas State, Venezuela. part 1: characterization of some epidemiological aspects

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    De Sousa Leonardo

    1997-01-01

    Full Text Available Scorpion poisoning was surveyed in Acosta and Caripe counties, located in the Turimiquire subregion of Monagas State, Venezuela, aiming to expand information on stings by characterizing some epidemiological aspects. From 1987 to 1993, 298 cases of scorpion stings were recorded in Acosta and Caripe counties. Acosta had 212 cases, with an annual incidence rate of 18.3‰(cases per 10,000 inhabitants and a period median incidence rate of 128‰. The scorpion poisoning index is 4.18 times greater in Acosta than in Caripe, confirming the former as a hyperendemic zone for this type of injury, with a phenomenon of cyclical temporal fluctuations and an upward trend. This area is infested with scorpions of the genus Tityus. Our results show that the region surveyed in Monagas State is endemic for scorpion stings, posing a major public health problem.

  12. Pathophysiology of dilatation of pupils due to scorpion and snake envenomation and its therapeutic value: Clinical observations

    Science.gov (United States)

    Bawaskar, Himmatrao S; Bawaskar, Parag H; Bawaskar, Pramodini H

    2017-01-01

    Dilated nonreacting pupils are routinely taken as a sign of irreversible brain damage. Alpha-receptor stimulation (scorpion sting) and presynaptic acetylcholine receptor blocker (krait bite) may result in dilation of pupils without involvement of the brain. This study was aimed to clinically evaluate the response of pupils in scorpion sting and krait bite. Victims of scorpion sting and krait bite were chosen from Raigad district. Scorpion sting and krait bite cases were admitted to hospital and were clinically evaluated in detail regarding neurological manifestations. Both cases had nonreacting dilation of pupils, complete neurological recovery accompanied with reverse of pupillary size and its response to light. In scorpion sting and krait bite poisoning, dilated nonreacting pupils are not the signs of irreversible brain damage. PMID:28300747

  13. Epidemiological aspect of scorpion sting in Bandar Abbas, Iran, during 2009–2011

    Science.gov (United States)

    Moosavy, Seyed Hamid; Shahi, Mehran; Rafinejad, Javad; Zare, Shahram; Madani, Abdoulhossain; Navidpour, Shahrokh

    2016-01-01

    Introduction People in tropical and semi-tropical areas are in danger of scorpion sting, and this can be a serious problem for them. Mortality due to scorpion sting in the tropical and semi-tropical areas of Iran is about 75%, and this makes scorpion sting in these areas a serious medical problem. Because of this problem, our aim was to assess the epidemiological aspects of scorpion sting in Bandar Abbas, Iran, during 2009–2011. Methods In this cross-sectional retrospective study, epidemiologic data of 698 scorpion sting cases, who were referred to the Shahid Mohamadi Hospital of Bandar Abbas in Hormozgan Province collected from 2009 until 2011. The data included demographic and individual information, such as age, gender, geographic location, bite site, when the incident occurred, and anti-venom consumption. The required data were extracted from the patients’ recorded information in the Hospital, and we recorded data in a special checklist and imported the data into the computer for statistical analysis using of SPSS software, version 21.0. Descriptive statistics, including mean, standard deviation, frequency, and percentage, were used for data analysis. Results Two hundred and sixty-one (37.4%) of the cases were urban and 437(62.6%) were rural. Males comprised 50.1% of the cases, and women comprised 49.9% (p >0.05). Twenty-five point two percent of scorpion sting cases occurred among people in the 21 to 30 age group, and there were very few cases among people in the 51 to 60 age range (p<0.05). Most of cases were recorded in April and October, and the fewest cases were recorded in July and January (p<0.05); also 32.2% of scorpion sting cases occurred after midnight and in the early morning hours. Conclusion Our survey showed that there was a high incidence of scorpion stings in rural areas, among 21–30 age group, among housekeepers, and among students. These results indicate the need for public education programs and better sanitation services in the rural

  14. New analysis of the toxic compounds from the Androctonus mauretanicus mauretanicus scorpion venom.

    Science.gov (United States)

    Oukkache, Naoual; Rosso, Jean-Pierre; Alami, Meriem; Ghalim, Norredine; Saïle, Rachid; Hassar, Mohammed; Bougis, Pierre E; Martin-Eauclaire, Marie-France

    2008-04-01

    Scorpion venoms are very complex mixtures of molecules, most of which are peptides displaying different kinds of biological activity. Indeed, these peptides specifically bind to a variety of pharmacological targets, in particular ionic channels located in prey tissues, resulting in neurotoxic effects. Toxins modulating Na+, K+, Ca2+ and Cl(-) currents have been described in scorpion venoms. In this work, we have used several specific antibodies raised against the most lethal scorpion toxins already described to screen the Moroccan scorpion Androctonus mauretanicus mauretanicus venom in order to characterize new compounds. This immunological screening was also implemented by toxicity tests in mice and with mass spectrometry study, providing new informations on the molecular composition of this venom. In fine, we were able to determine the molecular masses of 70-80 different compounds. According to the immunological data obtained, many toxins cross-react with three sera raised against the most lethal alpha-toxins found in North African scorpion venoms, but not at all with those raised against the main beta-toxins from South and North American venoms. Some of the previously described toxins from Androctonus mauretanicus mauretanicus venom could thus be detected by combining immunological tests, toxicity in mice and molecular masses. Among these toxins, one of them, which showed a mild cross-reaction with the serum raised against AaH I (a highly potent toxin from the venom of Androctonus australis), was identified as Amm III and fully sequenced.

  15. Consequences of Androctonus mauretanicus and Buthus occitanus scorpion venoms on electrolyte levels in rabbits

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    Khadija Daoudi

    2017-01-01

    Full Text Available Androctonus mauretanicus (A. mauretanicus and Buthus occitanus (B. occitanus scorpions, which belong to the Buthidae family, are the most venomous scorpions in Morocco. For the first time, we investigated the effects of such scorpion venoms on serum electrolytes in subcutaneously injected rabbits. For this purpose, 3 groups of 6 albinos adult male rabbits (New Zealand were used in this experiment. Two of the groups were given a single subcutaneous injection of either crude Am venom (5 μg/kg or Bo venom (8 μg/kg whereas the third group (control group only received physiological saline solution (NaCl 0.9%. The blood samples were collected from injected rabbits via the marginal vein at time intervals of 30 min, 1 h, 2 h, 4 h, 6 h and 24 h after venom injection. The concentrations of electrolytes in the serum samples were measured. Our study indicates that scorpion envenomation in vivo, rabbit animal model, caused severe and persistent hypomagnesaemia and hypochloremia, which are accompanied of hypernatremia, hyperkalemia and hypercalcaemia. The intensity of electrolytes imbalance was clearly superior in the case of A. mauretanicus scorpion venom (although a lower quantity of venom was injected. This is coherent with the experimental data which indicate that A. mauretanicus venom is more toxic than B. occitanus venom.

  16. Scorpionism in Central America, with special reference to the case of Panama

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    A Borges

    2012-01-01

    Full Text Available Scorpionism in the Americas occurs mainly in Mexico, northern South America and southeast Brazil. This article reviews the local scorpion fauna, available health statistics, and the literature to assess scorpionism in Central America. Notwithstanding its high toxicity in Mexico, most scorpion sting cases in Guatemala, Belize, El Salvador, Nicaragua, and Costa Rica are produced by species in the genus Centruroides that are only mildly toxic to humans despite the existence of ion channel-active toxins in their venoms. Regional morbidity is low with the exception of Panama, where an incidence of 52 cases per 100,000 inhabitants was recorded for 2007, with 28 deaths from 1998 to 2006. Taxa belonging to the genus Tityus (also present in the Atlantic coast of Costa Rica are responsible for fatalities in Panama, with Tityus pachyurus being the most important species medically. Most Tityus species inhabiting Panama are also found in northern South America from which they probably migrated upon closure of the Panamanian isthmus in the Miocene era. Incorporation of Panama as part of the northern South American endemic area of scorpionism is thereby suggested based on the incidence of these accidents and the geographical distribution of Panamanian Tityus species.

  17. Phylogenomic resolution of scorpions reveals multilevel discordance with morphological phylogenetic signal.

    Science.gov (United States)

    Sharma, Prashant P; Fernández, Rosa; Esposito, Lauren A; González-Santillán, Edmundo; Monod, Lionel

    2015-04-07

    Scorpions represent an iconic lineage of arthropods, historically renowned for their unique bauplan, ancient fossil record and venom potency. Yet, higher level relationships of scorpions, based exclusively on morphology, remain virtually untested, and no multilocus molecular phylogeny has been deployed heretofore towards assessing the basal tree topology. We applied a phylogenomic assessment to resolve scorpion phylogeny, for the first time, to our knowledge, sampling extensive molecular sequence data from all superfamilies and examining basal relationships with up to 5025 genes. Analyses of supermatrices as well as species tree approaches converged upon a robust basal topology of scorpions that is entirely at odds with traditional systematics and controverts previous understanding of scorpion evolutionary history. All analyses unanimously support a single origin of katoikogenic development, a form of parental investment wherein embryos are nurtured by direct connections to the parent's digestive system. Based on the phylogeny obtained herein, we propose the following systematic emendations: Caraboctonidae is transferred to Chactoidea new superfamilial assignment: ; superfamily Bothriuroidea revalidated: is resurrected and Bothriuridae transferred therein; and Chaerilida and Pseudochactida are synonymized with Buthida new parvordinal synonymies: .

  18. A first exploration of the venom of the Buthus occitanus scorpion found in southern France.

    Science.gov (United States)

    Martin-Eauclaire, Marie-France; Bosmans, Frank; Céard, Brigitte; Diochot, Sylvie; Bougis, Pierre E

    2014-03-01

    Even though Buthus occitanus scorpions are found throughout the Mediterranean region, a lack of distinctive characteristics has hampered their classification into different subspecies. Yet, stings from this particular scorpion family are reported each year to result in pain followed by various toxic symptoms. In order to determine the toxicity origin of the rare French B. occitanus Amoreux scorpion, we collected several specimens and studied their venom composition using a nano ultra high performance liquid chromatography and matrix assisted laser desorption/ionisation time-of-flight mass spectrometry (nano UHPLC/MALDI-TOF-MS) automated workflow combined with an enzyme-linked immunosorbent assay (ELISA) approach. Moreover, we compared this dataset to that obtained from highly lethal Androctonus australis and Androctonus mauretanicus scorpions collected in North Africa. As a result, we found that the B. occitanus Amoreux venom is toxic to mice, an observation that is most likely caused by venom components that inhibit voltage-gated sodium channel inactivation. Moreover, we identified similarities in venom composition between B. occitanus scorpions living in the South of France and other Buthidae collected in Morocco and Algeria. As such, the results of this study should be taken into consideration when treating stings from the B. occitanus species living in the South of France.

  19. Scorpion katoikogenic ovariuterus - Much more alike to apoikogenic type than it seemed to be.

    Science.gov (United States)

    Jędrzejowska, Izabela; Szymusiak, Kamil; Mazurkiewicz-Kania, Marta; Garbiec, Arnold

    2016-09-01

    Scorpions are viviparous matrotrophic arthropods. Both, fertilization and embryonic development occur in the female gonad called ovariuterus. Two distinct reproductive patterns are recognized among scorpions: apoikogenic and katoikogenic. In the ovariuterus of apoikogenic scorpions growing oocytes protrude from the ovarian wall and continue previtellogenic and vitellogenic growth on the gonad surface being accompanied by the follicular cells that cover the oocyte surface, and, in most families, the stalk cells that join the oocyte with the ovariuterus wall. In the katoikogenic ovariuterus the oocytes grow in outpocketings of the ovarian wall called diverticula. The aim of our study was to show the development and structure of the diverticula in two katoikogenic scorpions from the family Scorpionidae: Ophistothalmus boehmei and Heterometrus spinifer. We show that the somatic components of each diverticulum develop from the two epithelial layers of the ovariuterine wall. Before fertilization, the wall of the mature diverticula consists of two distinctive epithelial layers: an internal and an external one. Our observations reveal that the epithelial cells of the internal layer of the diverticulum show striking morphological resemblance to the follicular and stalk cells that accompany the growing oocytes in some apoikogenic scorpions. The external epithelial layer of the katoikogenic diverticulum seems to have no equivalents in the apoikogenic type. Functions of the somatic cells of the diverticulum are discussed.

  20. Evolutionary morphology of the hemolymph vascular system in scorpions: a character analysis.

    Science.gov (United States)

    Klußmann-Fricke, B-J; Prendini, L; Wirkner, C S

    2012-11-01

    Phylogenetically informative characters from the internal anatomy of scorpions were first reported more than 150 years ago, but the subject received little attention after the mid-1920s. Recent investigations, using traditional dissection, illustration and histological sectioning, microscopy, and innovative new methods for investigating complex soft tissue anatomy identified a new wealth of variation. Additionally, these investigations confirmed the phylogenetic significance of previously identified structures. Building on earlier work we present a more detailed description of the hemolymph vascular system (HVS) in scorpions, based on comparison of the vascular structures of the heart and the branching pattern of the prosomal arteries among 45 exemplar species representing most of the major scorpion lineages. Using corrosion-casting, MicroCT in combination with computer-aided 3D-reconstruction, and scanning electron microscopy, we conceptualize a series of phylogenetically informative characters for the anterior aorta system and characters of the heart and associated structures (e.g. arrangement of the ostia) of scorpions. Furthermore, we optimize the possible evolution of these new characters on a previous hypothesis of scorpion phylogeny, and discuss alternative character state transformations, their evolutionary consequences, and possible underlying evolutionary mechanisms acting on the HVS.

  1. Molecular evolution of scorpion a-toxins--Accelerated substitutions and functional divergence

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Scorpion α-toxins are a family of toxic proteins with similar scaffold, but possess divergent pharmacological properties.Analysis of cDNA sequences reveals that the numbers of nucleotide substitutions per site (K) for 5' and 3' UTRs are smaller than those per synonymous site (Ks) for the mature peptide-coding sequences, whereas the numbers of nucleotide substitutions per nonsynonymous site (Ka) are close to or larger than Ks values for relevant pairs of cDNAs. These results, together with phylogenetic analysis, indicate that scorpion a-toxins have evolved by accelerated substitutions in the mature toxin regions. In addition, the 15 amino acids, absolutely conserved in all the scorpion α-toxins described so far, are mostly located in molecular interior, which may be involved in structural constraints for stabilizing the CSαβ fold in evolution of these molecules. Four hot spot mutation sites in the molecular surface are found to dis tribute in the putative functional regions of α-toxins, suggesting that positive Darwinian selection drives the accelerated evolution of scorpion α-toxins. These findings reasonably explain the relationship between three-dimensional structure conservation and functional divergence of scorpion α-toxins and are of important value in guiding us in our engineering experiments to obtain higher affinity ligands to Na+ channels.

  2. Watch Out for Your Neighbor: Climbing onto Shrubs Is Related to Risk of Cannibalism in the Scorpion Buthus cf. occitanus

    Science.gov (United States)

    Urbano-Tenorio, Fernando

    2016-01-01

    The distribution and behavior of foraging animals usually imply a balance between resource availability and predation risk. In some predators such as scorpions, cannibalism constitutes an important mortality factor determining their ecology and behavior. Climbing on vegetation by scorpions has been related both to prey availability and to predation (cannibalism) risk. We tested different hypotheses proposed to explain climbing on vegetation by scorpions. We analyzed shrub climbing in Buthus cf. occitanus with regard to the following: a) better suitability of prey size for scorpions foraging on shrubs than on the ground, b) selection of shrub species with higher prey load, c) seasonal variations in prey availability on shrubs, and d) whether or not cannibalism risk on the ground increases the frequency of shrub climbing. Prey availability on shrubs was compared by estimating prey abundance in sticky traps placed in shrubs. A prey sample from shrubs was measured to compare prey size. Scorpions were sampled in six plots (50 m x 10 m) to estimate the proportion of individuals climbing on shrubs. Size difference and distance between individuals and their closest scorpion neighbor were measured to assess cannibalism risk. The results showed that mean prey size was two-fold larger on the ground. Selection of particular shrub species was not related to prey availability. Seasonal variations in the number of scorpions on shrubs were related to the number of active scorpions, but not with fluctuations in prey availability. Size differences between a scorpion and its nearest neighbor were positively related with a higher probability for a scorpion to climb onto a shrub when at a disadvantage, but distance was not significantly related. These results do not support hypotheses explaining shrub climbing based on resource availability. By contrast, our results provide evidence that shrub climbing is related to cannibalism risk. PMID:27655347

  3. Forecasting and prediction of scorpion sting cases in Biskra province, Algeria, using a seasonal autoregressive integrated moving average model.

    Science.gov (United States)

    Selmane, Schehrazad; L'Hadj, Mohamed

    2016-01-01

    The aims of this study were to highlight some epidemiological aspects of scorpion envenomations, to analyse and interpret the available data for Biskra province, Algeria, and to develop a forecasting model for scorpion sting cases in Biskra province, which records the highest number of scorpion stings in Algeria. In addition to analysing the epidemiological profile of scorpion stings that occurred throughout the year 2013, we used the Box-Jenkins approach to fit a seasonal autoregressive integrated moving average (SARIMA) model to the monthly recorded scorpion sting cases in Biskra from 2000 to 2012. The epidemiological analysis revealed that scorpion stings were reported continuously throughout the year, with peaks in the summer months. The most affected age group was 15 to 49 years old, with a male predominance. The most prone human body areas were the upper and lower limbs. The majority of cases (95.9%) were classified as mild envenomations. The time series analysis showed that a (5,1,0)×(0,1,1)12 SARIMA model offered the best fit to the scorpion sting surveillance data. This model was used to predict scorpion sting cases for the year 2013, and the fitted data showed considerable agreement with the actual data. SARIMA models are useful for monitoring scorpion sting cases, and provide an estimate of the variability to be expected in future scorpion sting cases. This knowledge is helpful in predicting whether an unusual situation is developing or not, and could therefore assist decision-makers in strengthening the province's prevention and control measures and in initiating rapid response measures.

  4. Clinico-epidemiology of stings and envenoming of Hottentotta tamulus (Scorpiones: Buthidae), the Indian red scorpion from Jaffna Peninsula in northern Sri Lanka.

    Science.gov (United States)

    Kularatne, Senanayake A M; Dinamithra, Nandana P; Sivansuthan, Sivapalan; Weerakoon, Kosala G A D; Thillaimpalam, Bhanu; Kalyanasundram, Vithiya; Ranawana, Kithsiri B

    2015-01-01

    In recent years, stings of a lethal scorpion species were recorded from Jaffna Peninsula in the northern dry zone of Sri Lanka. This species was identified as Hottentotta tamulus (Scorpiones: Buthidae) which is the Indian red scorpion commonly found in Maharashtra, India. The Teaching Hospital, Jaffna recorded 84 H. tamulus stings over a year in 2012 and of them, 23 cases provided offending scorpions (proven cases). Three localities in Jaffna were recorded as hotspots of scorpion stings namely Palali, Achchuvali and Karainagar. Of the proven cases, 13 (57%) and 10 (43%) were males and females respectively and had a mean age of 30 years (SD ± 20 years). Among them, 5 (22%) were children below 12 years. In 13 (57%) patients stings occurred inside their houses including two children (40%). Six (26%) stings occurred at night when the victims were in sleep. Median time taken to arrive at the hospital from the time of stinging was 58 min (range 8-550 min). Signs of over activation of autonomic nervous system predominated the clinical picture-tachycardia in 14 (61%), high blood pressure in 11 (48%), excessive sweating in 9 (39%), excessive salivation in 5 (22%), hypotension in 4 (17%) and piloerection in 3 (13%). Children showed higher predilection to develop tachycardia - 4 (80%) and excessive salivation - 3 (60%). Priapism was not observed and 17 (74%) patients have developed intense pain at the site of sting. The commonest ECG change was tachycardia (73%) and occasional T wave inversion. Prazosin as a treatment was given to 22 (96%) patients. All patients made recovery and 13 (57%) patients left the hospital within two days. In future, there is a potential risk of spreading this species to elsewhere in the country and may disturb the ecological balance.

  5. Allosteric modulation of neurotoxin binding to voltage-sensitive sodium channels by Ptychodiscus brevis toxin 2.

    Science.gov (United States)

    Sharkey, R G; Jover, E; Couraud, F; Baden, D G; Catterall, W A

    1987-03-01

    The effects of Ptychodiscus brevis toxin 2 (PbTx-2) on the binding of neurotoxins at four different neurotoxin receptor sites on voltage-sensitive sodium channels in rat brain synaptosomes were examined. Binding of saxitoxin at neurotoxin receptor site 1 and Leiurus quinquestriatus alpha-scorpion toxin (LqTx) at neurotoxin receptor site 3 was unaffected. PbTx-2 enhanced binding of batrachotoxinin A 20-alpha-benzoate (BTX-B) to neurotoxin receptor site 2 and Centruroides suffusus suffusus beta-scorpion toxin (CsTx II) to site 4 on sodium channels. These results support the proposal that PbTx-2 and related toxins act at a new receptor site (site 5) that has not been previously analyzed in binding experiments. Half-maximal effects of PbTx-2 were observed in the range of 20-50 nM PbTx-2. The enhancement of BTX-B binding was reduced by depolarization. Saturating concentrations of PbTx-2 reduced KD values for binding of BTX-B and CsTx-II 2.9-fold and 2.6-fold, respectively. The effects of PbTx-2 and LqTx in enhancing BTX-B binding were synergistic. A model involving both preferential binding of BTX-B, PbTx-2, LqTx, and CsTx II to active states of sodium channels and allosteric interactions among the four receptor sites at which these toxins act accommodates these and previous results.

  6. The mitochondrial genome sequence of the scorpion Centruroides limpidus (Karsch 1879) (Chelicerata; Arachnida).

    Science.gov (United States)

    Dávila, Sonia; Piñero, Daniel; Bustos, Patricia; Cevallos, Miguel A; Dávila, Guillermo

    2005-11-07

    The mitochondrial genome of the scorpion Centruroides limpidus (Chelicerata; Arachnida) has been completely sequenced and is 14519 bp long. The genome contains 13 protein-encoding genes, two ribosomal RNA genes, 21 transfer RNA genes and a large non-coding region related to the control region. The overall A+T composition is the lowest among the complete mitochondrial sequences published within the Chelicerata subphylum. Gene order and gene content differ slightly from that of Limulus polyphemus (Chelicerata: Xiphosura): i.e., the lack of the trnD gene, and the translocation-inversion of the trnI gene. Preliminary phylogenetic analysis of some Chelicerata shows that scorpions (C. limpidus and Mesobuthus gibbosus) make a tight cluster with the spiders (Arachnida; Araneae). Our analysis does not support that Scorpiones order is the sister group to all Arachnida Class, since it is closer to Araneae than to Acari orders.

  7. Morphology and ontogeny of the pectines of Babycurus jacksoni (Scorpiones: Buthidae)

    DEFF Research Database (Denmark)

    Funch, Peter; Thybring, Mette

    Pectines are unique mechano- and chemosensory organs of scorpions used in prey capture and mating. All extant species possess one pair of these comb-like sensory structures ventrally on the second mesosomal segment, and each pecten is composed of marginal and medial lamellae that carry numerous...... pectinal teeth with ventral microscopic sensory pegs. Here we studied the ontogeny and morphology of the pectines in the Tanzanian red bark scorpion, Babycurus jacksoni by comparison of size and morphology of their exuvia and pectines from first instar to adult. Light- and scanning electron microscopy...... was unexpec-ted because of the important role of pectines in courtship behaviour. The cuticular spikes found here has not been reported from scorpion pectines before and their function should be further investigated. The undeveloped pegs in the first instar are probably not fully functional in agreement...

  8. Venom-spraying behavior of the scorpion Parabuthus transvaalicus (Arachnida: Buthidae).

    Science.gov (United States)

    Nisani, Zia; Hayes, William K

    2015-06-01

    Many animals use chemical squirting or spraying behavior as a defensive response. Some members of the scorpion genus Parabuthus (family Buthidae) can spray their venom. We examined the stimulus control and characteristics of venom spraying by Parabuthus transvaalicus to better understand the behavioral context for its use. Venom spraying occurred mostly, but not always, when the metasoma (tail) was contacted (usually grasped by forceps), and was absent during stinging-like thrusts of the metasoma apart from contact. Scorpions were significantly more likely to spray when contact was also accompanied by airborne stimuli. Sprays happened almost instantaneously following grasping by forceps (median=0.23s) as a brief (0.07-0.30s, mean=0.18s), fine stream (scorpion predators. Successive venom sprays varied considerably in duration and velocity. Collectively, these results suggest that venom spraying might be useful as an antipredator function and can be modulated based on threat.

  9. Study of biomechanical, anatomical, and physiological properties of scorpion stingers for developing biomimetic materials.

    Science.gov (United States)

    Zhao, Zi-Long; Shu, Tao; Feng, Xi-Qiao

    2016-01-01

    Through natural selection, many animal organs have evolved superior mechanical properties and elegant hierarchical structures adaptive to their multiple biological functions. We combine experiments and theory to investigate the composition-structure-property-function relations of scorpion stingers. Their hierarchical structures and functionally gradient mechanical properties were revealed. Slow motion analysis of the penetration process of a scorpion stinger was performed to examine the refined survival skills of scorpions. An experiment-based mechanics model of the stinger was proposed, the results of which revealed an optimized range of penetration angle in an insertion event. Both theoretical and numerical results are in good agreement with our experimental measurements. The analysis method and physical insights of this work are potentially important for investigating a general class of sharp-edge biological materials, e.g., cattle horns, spider fangs, cat claws, and plant thorns.

  10. Scorpion sting envenomation presenting with pulmonary edema in adults: A report of seven cases from Nepal

    Directory of Open Access Journals (Sweden)

    Bhadani Umesh

    2006-01-01

    Full Text Available Scorpion sting is a common problem in villages of Eastern Nepal. The life-threatening complications of myocarditis and pulmonary edema is known in red scorpion in India but not reported in Nepal. This condition requires urgent attention and ICU care from few hours to days. Delay in recognition and the hypoxemia increase the morbidity and mortality. Illiteracy, ignorance, poverty, traditional faith healers trying treatment in remote areas, lack of transport in difficult terrains and the non availability of ventilation facility in nearby hospital, add to delay in appropriate treatment. Seven young adult patients admitted in a span of two years with history of scorpion sting presenting with pulmonary edema required ICU care. They were successfully managed with the positive pressure ventilation with PEEP, cardiac support with inotropes and fluid balance. Magnitude of problem, clinical presentation and management done is emphasized.

  11. Clinical comparison of scorpion envenomation by Androctonus mauritanicus and Buthus occitanus in children.

    Science.gov (United States)

    Aboumaâd, Bouchra; Lahssaini, Mohammed; Tiger, Abdelaziz; Benhassain, Sidi Mohammed

    2014-11-01

    The clinical results of scorpion stings by Androctonus mauritanicus (Am) and Buthus occitanus (Bo) (main sources of scorpionism in Morocco) were evaluated in this work. The objective was to compare the clinical manifestations of envenoming from these species by investigating possible correlations among symptoms/signs and laboratory abnormalities of envenomed patients. 41 children (25 males, 18 months - 11 years) were admitted at the Provincial Hospital of El Jadida-Morocco. Their minor (18 children) or severe (23 children) systemic signs such as pallor (48.8%), pulmonary edema (APE) (36.6%), convulsion (26.8%), coma (7.3%) were more frequent in children envenomed by Am than Bo, but angioedema (Quincke's edema) (4.9%) was particularly developed in the latter group. The laboratory blood abnormalities (hyperglycemia, high levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatinine, bilirubin, leukocytes, neutrophils, monocytes, platelets and low levels of lymphocytes and hemoglobin) were significantly higher (p forecast the fatal outcome in scorpion envenomation.

  12. Structural and functional diversity of acidic scorpion potassium channel toxins.

    Directory of Open Access Journals (Sweden)

    Zong-Yun Chen

    Full Text Available BACKGROUND: Although the basic scorpion K(+ channel toxins (KTxs are well-known pharmacological tools and potential drug candidates, characterization the acidic KTxs still has the great significance for their potential selectivity towards different K(+ channel subtypes. Unfortunately, research on the acidic KTxs has been ignored for several years and progressed slowly. PRINCIPAL FINDINGS: Here, we describe the identification of nine new acidic KTxs by cDNA cloning and bioinformatic analyses. Seven of these toxins belong to three new α-KTx subfamilies (α-KTx28, α-KTx29, and α-KTx30, and two are new members of the known κ-KTx2 subfamily. ImKTx104 containing three disulfide bridges, the first member of the α-KTx28 subfamily, has a low sequence homology with other known KTxs, and its NMR structure suggests ImKTx104 adopts a modified cystine-stabilized α-helix-loop-β-sheet (CS-α/β fold motif that has no apparent α-helixs and β-sheets, but still stabilized by three disulfide bridges. These newly described acidic KTxs exhibit differential pharmacological effects on potassium channels. Acidic scorpion toxin ImKTx104 was the first peptide inhibitor found to affect KCNQ1 channel, which is insensitive to the basic KTxs and is strongly associated with human cardiac abnormalities. ImKTx104 selectively inhibited KCNQ1 channel with a K(d of 11.69 µM, but was less effective against the basic KTxs-sensitive potassium channels. In addition to the ImKTx104 toxin, HeTx204 peptide, containing a cystine-stabilized α-helix-loop-helix (CS-α/α fold scaffold motif, blocked both Kv1.3 and KCNQ1 channels. StKTx23 toxin, with a cystine-stabilized α-helix-loop-β-sheet (CS-α/β fold motif, could inhibit Kv1.3 channel, but not the KCNQ1 channel. CONCLUSIONS/SIGNIFICANCE: These findings characterize the structural and functional diversity of acidic KTxs, and could accelerate the development and clinical use of acidic KTxs as pharmacological tools and

  13. The Epidemiologic Status of Scorpion Stings in Qom Province, 2001-2011

    Directory of Open Access Journals (Sweden)

    Saghafipour A

    2013-01-01

    Full Text Available AbstractBackgrounds and Aims: In the tropical regions of Iran, scorpion stings are one of the most important medical and health problems. Knowing about their epidemiologic aspects might lead to the employment of appropriate preventive methods. Therefore, these studies were done in Qom province for this purpose.Materials and Methods: This research is a descriptive cross-sectional study which has been done in all of the urban and rural areas of Qom province from 2001 to 2011, and all the cases which were referred to the only available hospital were assessed, examined, treated and subsequently followed. Finally, a questionnaire including demographic, epidemiologic and clinical data was completed for the patients. Chi square tests were used for the evaluation of the hypothesis.Results: In total, 790 cases of scorpion stings were referred to the hospital during the period of study. Most of the cases were males (60.25% in the 10-24 age groups. The most cases occurred during spring and summer. Hands and feet were the most common location of scorpion stings. 18.7 % of envenomed cases were due to black scorpions. 74.4 % of cases were from rural regions. 77.2% of the sufferers slept outdoors and on the ground. 20.5% of cases were surrounded by timber, dust and building materials.Conclusion: Based on these findings, scorpion stings are considered a public health problem in Qom province. Consequently, it is necessary to introduce health education programs for personal protection, in order to prevent possible injuries from scorpions, especially for the boy students that reside in rural areas. Also the villagers should use proper beds to sleep in the outdoors.

  14. Clinical and Laboratory Characteristics of Pediatric Scorpion Stings: A Report From Southern Iran.

    Science.gov (United States)

    Dehghankhalili, Maryam; Mobaraki, Hossein; Akbarzadeh, Armin; Yazdani, Reza; Nazemi, Abdolmajid; Ghaffarpasand, Fariborz; Mohammadi, Zahra; Shahrzad, Mohammad Esmaeil; Mohmudi, Forugh; Taghavi, Mohsen; Dehghankhalili, Saeed

    2017-06-01

    Scorpion stings are a major public health problem in many countries, particularly in pediatrics. Children are more susceptible to severe clinical manifestations of envenomation. The aim of this study is to determine the epidemiological and clinical characteristics of pediatric scorpionism in Hormozgan province of Iran during 2012. This was a cross-sectional study being conducted during 2010 in Hormozgan, the southern province of Iran. We included 350 patients admitted to emergency unit of the hospitals of 8 cities of Hormozgan with impression of scorpion envenomation. The clinical and epidemiological characteristics as well as the treatment and outcome were recorded. The prevalence rate of pediatric scorpion stings in the province was 1.8 in 1000 children. The mean age of the patients was 5.75 ± 4.54 (range, 1-18) years. There were 208 (59.5%) boys and 142 (40.5%) girls among the patients. The most common site of sting was sole to knee in 94 (26.8%) followed by hand in 61 (17.4%) and fingers in 47 (13.4%). The most common presenting symptom was vomiting in 236 (67.4%) followed by localized pain in 131 (37.3%), erythema in 120 (34.2%), and edema in 119 (33.9%). The highest and lowest frequency occurred in July (17.7%) and January (3.2%), respectively. Nocturnal envenomations (53.7%) were more common than diurnal (46.3%). Most of scorpionism were mild (83.4%) that all evolved to cure, without any deaths. The results demonstrate the pediatric scorpionism is a public health problem in Hormozgan province of Iran, and special attention should be paid to prevention and treatment.

  15. Partial transcriptomic profiling of toxins from the venom gland of the scorpion Parabuthus stridulus.

    Science.gov (United States)

    Mille, Bea G; Peigneur, Steve; Diego-García, Elia; Predel, Reinhard; Tytgat, Jan

    2014-06-01

    Since it is an apocrine secretion, scorpion venom is a complex mixture that contains a variety of low-molecular-weight basic proteins (neurotoxins), mucus, salts, as well as a large number of other constituents. Diversity of scorpion venom peptides exists also at the transcript level. Two kinds of venom peptides are typically considered: the neurotoxins and the antimicrobial peptides. We constructed a cDNA library and carried an EST (Expressed Sequence Tag) approach to overview the different peptides in the transcriptome of the telson from Parabuthus stridulus. P. stridulus are psammophilous and highly venomous scorpions endemic to Namibia (Prendini 2004) with medical relevance because of important human envenomation occurrence. We obtained 111 ESTs, 20% of them corresponding to cellular process transcripts, 7% to hypothetical proteins and 17% were sequences without good matches, but the majority of ESTs, 56%, corresponds to transcripts encoding for different venom components, including voltage-gated sodium, potassium and calcium channel toxins, antimicrobial peptides and other venom and cell proteins. To the best of our knowledge this report contains the first transcriptome analysis of genes transcribed by the venomous gland of the scorpion species P. stridulus, belonging to the family of medically important Buthidae scorpions. One hundred and eleven ESTs were analyzed, showing an important number of genes that encode for products similar to known scorpion venom components. In total, 17 unique and novel sequences were indentified. The identification and characterization of these compounds will be a good source of novel pharmacological tools for studying ion channels and the understanding of the physiological effects of toxins in P. stridulus envenomations at a molecular level.

  16. Similar burrow architecture of three arid-zone scorpion species implies similar ecological function

    Science.gov (United States)

    Adams, Amanda M.; Marais, Eugene; Turner, J. Scott; Prendini, Lorenzo; Pinshow, Berry

    2016-08-01

    Many animals reside in burrows that may serve as refuges from predators and adverse environmental conditions. Burrow design varies widely among and within taxa, and these structures are adaptive, fulfilling physiological (and other) functions. We examined the burrow architecture of three scorpion species of the family Scorpionidae: Scorpio palmatus from the Negev desert, Israel; Opistophthalmus setifrons, from the Central Highlands, Namibia; and Opistophthalmus wahlbergii from the Kalahari desert, Namibia. We hypothesized that burrow structure maintains temperature and soil moisture conditions optimal for the behavior and physiology of the scorpion. Casts of burrows, poured in situ with molten aluminum, were scanned in 3D to quantify burrow structure. Three architectural features were common to the burrows of all species: (1) a horizontal platform near the ground surface, long enough to accommodate the scorpion, located just below the entrance, 2-5 cm under the surface, which may provide a safe place where the scorpion can monitor the presence of potential prey, predators, and mates and where the scorpion warms up before foraging; (2) at least two bends that might deter incursion by predators and may reduce convective ventilation, thereby maintaining relatively high humidity and low temperature; and (3) an enlarged terminal chamber to a depth at which temperatures are almost constant (±2-4 °C). These common features among the burrows of three different species suggest that they are important for regulating the physical environment of their inhabitants and that burrows are part of scorpions' "extended physiology" ( sensu Turner, Physiol Biochem Zool 74:798-822, 2000).

  17. Induction of neutralizing antibodies in mice immunized with scorpion toxins detoxified by liposomal entrapment

    OpenAIRE

    1997-01-01

    The possibility of producing neutralizing antibodies against the lethal effects of scorpion toxins was evaluated in the mouse model by immunization with an immunogen devoid of toxicity. A toxic fraction (5 mg) from the venom of the scorpion Tityus serrulatus was entrapped in sphingomyelin-cholesterol liposomes. The liposomes were treated for 1 h at 37oC with a 1% (w/w) trypsin solution in 0.2 M sodium carbonate buffer, pH 8.3. This treatment led to a strong reduction in venom toxicity. Immuni...

  18. Potency of insect-specific scorpion toxins on mosquito control using Bacillus thuringiensis Cry4Aa.

    Science.gov (United States)

    Matsumoto, Riku; Shimizu, Yoshitaka; Howlader, Mohammad Tofazzal Hossain; Namba, Maho; Iwamoto, Aya; Sakai, Hiroshi; Hayakawa, Tohru

    2014-06-01

    Two insect-specific scorpion toxins, BjαIT and AahIT were produced as alkali-soluble protein inclusions in Escherichia coli. The inclusion bodies themselves exhibited no toxicity against Culex pipiens larvae. However, coadministration with Cry4Aa toxin enhanced the mosquitocidal activity by 2-3 fold. Insect-specific scorpion toxins can be good supplements for Cry toxin-based bioinsecticides. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  19. Stings from Euscorpius flavicaudis (De Geer, 1778 (Scorpiones, Euscorpiidae during pregnancy: a clinical case report

    Directory of Open Access Journals (Sweden)

    M Dutto

    2012-01-01

    Full Text Available We report a case in which a 21-week pregnant woman was stung by a Euscorpius flavicaudis (De Geer, 1778 scorpion. Symptoms and signs experienced by the patient were the same as those documented in the literature and with no ill-effects for the pregnancy. Envenoming was local and of low degree of intensity. It is important to emphasize that the patient was stung in her home, which differs from stings in most other parts of the world, in which scorpionism is mostly a risk in outdoor areas.

  20. Detection of Hepatitis B Virus DNA by Duplex Scorpion Primer-based PCR Assay

    Institute of Scientific and Technical Information of China (English)

    KONG De-Ming孔德明; SHEN Han-Xi沈含熙; MI Huai-Feng宓怀风

    2004-01-01

    The application of a new fiuorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant of duplex Amplifluor, and the incorporation of a PCR stopper between probe and primer sequences improve the detection specificity and sensitivity. Combined with PCR amplification, this probe can give unambiguous positive results for the reactions initiated with more than 20 HBV molecules. In addition, the particular unimolecular probing mechanism of this probe makes the use of short target-specific probe sequence possible, which will render this probe applicable in some specific systems.

  1. Embriotoxic effects of maternal exposure to Tityus serrulatus scorpion venom

    Directory of Open Access Journals (Sweden)

    A. A. S. Barão

    2008-01-01

    Full Text Available Tityus serrulatus is the most venomous scorpion in Brazil; however, it is not known whether its venom causes any harm to the offspring whose mothers have received it. This study investigates whether the venom of T. serrulatus may lead to deleterious effects in the offspring, when once administered to pregnant rats at a dose that causes moderate envenomation (3mg/kg. The venom effects were studied on the 5th and on the 10th gestation day (GD5 and GD10. The maternal reproductive parameters of the group that received the venom on GD5 showed no alteration. The group that received the venom on GD10 presented an increase in post-implantation losses. In this group, an increase in the liver weight was also observed and one-third of the fetuses presented incomplete ossification of skull bones. None of the groups that received the venom had any visceral malformation or delay in the fetal development of their offspring. The histopathological analysis revealed not only placentas and lungs but also hearts, livers and kidneys in perfect state. Even having caused little effect on the dams, the venom may act in a more incisive way on the offspring, whether by stress generation or by a direct action.

  2. Peptides from the scorpion Vaejovis punctatus with broad antimicrobial activity.

    Science.gov (United States)

    Ramírez-Carreto, Santos; Jiménez-Vargas, Juana María; Rivas-Santiago, Bruno; Corzo, Gerardo; Possani, Lourival D; Becerril, Baltazar; Ortiz, Ernesto

    2015-11-01

    The antimicrobial potential of two new non-disulfide bound peptides, named VpAmp1.0 (LPFFLLSLIPSAISAIKKI, amidated) and VpAmp2.0 (FWGFLGKLAMKAVPSLIGGNKSSSK) is here reported. These are 19- and 25-aminoacid-long peptides with +2 and +4 net charges, respectively. Their sequences correspond to the predicted mature regions from longer precursors, putatively encoded by cDNAs derived from the venom glands of the Mexican scorpion Vaejovis punctatus. Both peptides were chemically synthesized and assayed against a variety of microorganisms, including pathogenic strains from clinical isolates and strains resistant to conventional antibiotics. Two shorter variants, named VpAmp1.1 (FFLLSLIPSAISAIKKI, amidated) and VpAmp2.1 (FWGFLGKLAMKAVPSLIGGNKK), were also synthesized and tested. The antimicrobial assays revealed that the four synthetic peptides effectively inhibit the growth of both Gram-positive (Staphylococcus aureus and Streptococcus agalactiaea) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria, with MICs in the range of 2.5-24.0 μM; yeasts (Candida albicans and Candida glabrata) with MICs of 3.1-50.0 μM; and two clinically isolated strains of Mycobacterium tuberculosis-including a multi-drug resistant one- with MICs in the range of 4.8-30.5 μM. A comparison between the activities of the original peptides and their derivatives gives insight into the structural/functional role of their distinctive residues.

  3. An ERG channel inhibitor from the scorpion Buthus eupeus

    DEFF Research Database (Denmark)

    Korolkova, Y.V.; Kozlov, S.A.; Lipkin, A.V.

    2001-01-01

    that the precursor contains a signal peptide of 21 amino acid residues. The mature toxin consists of 36 amino acid residues. BeKm-1 belongs to the family of scorpion venom potassium channel blockers and represents a new subgroup of these toxins. The recombinant BeKm-1 was produced as a Protein A fusion product...... and the three mutants partly inhibited the native M-like current in NG108-15 at 100 nm. The effect of the recombinant BeKm-1 on different K(+) channels was also studied. BeKm-1 inhibited hERG1 channels with an IC(50) of 3.3 nm, but had no effect at 100 nm on hEAG, hSK1, rSK2, hIK, hBK, KCNQ1/KCNE1, KCNQ2/KCNQ3......, KCNQ4 channels, and minimal effect on rELK1. Thus, BeKm-1 was shown to be a novel specific blocker of hERG1 potassium channels....

  4. Primer registro de Tityus trivittatus (Scorpiones: Buthidae en la provincia de Mendoza (Argentina First record of Tityus trivittatus (Scorpiones: Buthidae in Mendoza province (Argentina

    Directory of Open Access Journals (Sweden)

    Florencia Fernández Campón

    2009-06-01

    Full Text Available En la siguiente nota se informa sobre el primer registro del escorpión Tityus trivittatus Kraepelin en la provincia de Mendoza en el Barrio Campo Papa, departamento de Godoy Cruz. T trivittatus es dentro de nuestro país una de las especies de escorpiones con importancia médica, debido a que su veneno neurotóxico puede causar lesiones en el sistema nervioso y en algunos casos la muerte, particularmente en niños.This note reports the first record on the scorpion Tityus trivittatus Kraepelin in Mendoza province in the locality of Campo Papa, Godoy Cruz. T. trivittatus is one of the species of scorpion of medical importance in Argentina, due to the fact that its neurotoxic venom can damage the nervous system and may even be fatal in some cases, especially among children.

  5. Clinical and epidemiological aspects of scorpion stings in the northeast region of Brazil

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    Rafaella Moreno Barros

    2014-04-01

    Full Text Available Scorpion stings are a serious public health issue in tropical and subtropical countries. This is a descriptive and retrospective study of the clinical-epidemiological characteristics of scorpion sting cases registered in the Health System in the city of Campina Grande, Paraíba state, from 2007 to 2012. Data was collected from the Injury Notification Information System data banks of the Ministry of Health. A total of 2,283 records, provided by the Third Health Sector of Campina Grande, were analyzed. Data revealed that the majority of the victims are female aged between 20 and 29 years, and the highest incidence of stings was in the urban area. Victims were mostly stung on the feet and hand. Serotherapy was not administered in most cases. The majority of the victims received medical assistance within 1 to 3 hours after the sting. The most prevalent clinical manifestations were pain, edema and paresthesias. Most cases were classified as mild, though seven deaths were reported. The high incidence rate suggests that this town may be an endemic area of scorpion stings, supporting the need to develop strategies to control and prevent scorpion stings.

  6. Splicing of scorpion toxin gene BmKK2 in HEK 293T cells.

    Science.gov (United States)

    Zhijian, Cao; Chao, Dai; Shijin, Yin; Yingliang, Wu; Jiqun, Sheng; Yonggang, Sha; Wenxin, Li

    2006-01-01

    Using GFP as a reporter gene, splicing of scorpion toxin gene BmKK2 was investigated in cultured HEK 293T cells. The results of RT-PCR and western blotting showed that BmKK2's intron could be recognized and spliced in cultured HEK 293T cells. At the same time, a cryptic splicing site of BmKK2 gene was found at the 91st nucleotide site of the second exon, which is a typical form of alternative splicing. For the first time, alternative splicing would partially explain the diversity of scorpion toxins at the gene level. Moreover, replacing BmKK2's intron with BmP03's intron (an artificial BmKK2-BmP03 mosaic gene) did not affect the intron's recognition and splicing, but increased the expression of the toxin-GFP fusion protein by fluorescence imaging, which indicated that both introns may regulate the expression of toxin-GFP fusion protein. The artificial BmKK2-BmP03 mosaic gene was also spliced into two kinds of mRNA molecules, which showed that sequence of intron was not absolutely conserved. The results suggested that introns of scorpion toxin genes BmKK2 and BmP03 increase the diversity of scorpion toxins and regulate the expression of their genes. 2006 Wiley Periodicals, Inc.

  7. Tris(pyrazolyl)phosphine oxide and Tris(triazolyl)phosphine oxide scorpion ligands

    NARCIS (Netherlands)

    Tazelaar, Cornelis G J; Lyaskovskyy, Volodymyr; Van Doorn, Ilana M.; Schaapkens, Xander; Lutz, Martin; Ehlers, Andreas W.; Slootweg, Jack; Lammertsma, Koop

    2014-01-01

    DFT calculations were performed on copper(I) complexes of neutral scorpion ligands based on either pyrazolyl (Pz) or triazolyl (Tz) rings with both methane and phosphine oxide apexes, that is, HC(Pz)3, OP(Pz)3, HC(Tz)3, and OP(Tz)3. The analyses reveal that all four ligands have similar donor proper

  8. Clinical and epidemiological aspects of scorpion stings in the northeast region of Brazil.

    Science.gov (United States)

    Barros, Rafaella Moreno; Pasquino, Jackeline Araujo; Peixoto, Laisla Rangel; Targino, Isabely Tamarys Gomes; de Sousa, Jorge Alves; Leite, Renner de Souza

    2014-04-01

    Scorpion stings are a serious public health issue in tropical and subtropical countries. This is a descriptive and retrospective study of the clinical-epidemiological characteristics of scorpion sting cases registered in the Health System in the city of Campina Grande, Paraíba state, from 2007 to 2012. Data was collected from the Injury Notification Information System data banks of the Ministry of Health. A total of 2,283 records, provided by the Third Health Sector of Campina Grande, were analyzed. Data revealed that the majority of the victims are female aged between 20 and 29 years, and the highest incidence of stings was in the urban area. Victims were mostly stung on the feet and hand. Serotherapy was not administered in most cases. The majority of the victims received medical assistance within 1 to 3 hours after the sting. The most prevalent clinical manifestations were pain, edema and paresthesias. Most cases were classified as mild, though seven deaths were reported. The high incidence rate suggests that this town may be an endemic area of scorpion stings, supporting the need to develop strategies to control and prevent scorpion stings.

  9. A new species of Auyantepuia González-Sponga, 1978 (Scorpiones, Chactidae) from French Guiana.

    Science.gov (United States)

    Ythier, Eric

    2015-01-01

    A new species of scorpion belonging to the genus Auyantepuia González-Sponga, 1978 (family Chactidae Pocock, 1893) is described on the basis of three specimens collected in a rainforest formation located in Saut Sabbat, South of Mana, French Guiana. This is the tenth species of the Guiano-Amazonian genus Auyantepuia, and the fifth reported from French Guiana.

  10. Peripheral and central effects of intracerebroventricular microinjection of Hottentotta gentili (Pallary, 1924) (Scorpiones, Buthidae) venom.

    Science.gov (United States)

    El Hidan, Moulay Abdelmonaim; Touloun, Oulaid; El Hiba, Omar; Laadraoui, Jawad; Ferehan, Hind; Boumezzough, Ali

    2016-03-01

    Central effects of scorpion venom toxins have been neglected, due both to the common belief that scorpion venoms act by targeting peripheral organs and also to the misunderstanding that these peptides do not cross the brain-blood barrier (BBB). Determining whether scorpion neurotoxicity is restricted to peripheral actions or whether a central mechanism may be partly responsible for systemic manifestations could be crucial in clinical therapy trends. The present study therefore aims to assess histopathological damages in some organs (heart, kidney, liver, and lungs) and the related biochemical impairments, together with a neurobehavioral investigation following an intracerebroventricular (i.c.v) micro-injection of Hottentotta gentili (Scorpiones, Buthidae) venom (0.47 μg/kg). I.c.v. injection of venom produced focal fragmentation of myocardial fibers, while lungs showed rupture of the alveolar structure. Concurrently, there was a significant rise in the serum enzymes levels of ASAT, ALAT, CPK and LDH. Meanwhile, we observed behavioral alterations such as a hypoactivity, and in addition the venom seems to have a marked anxiogenic-like effect. The present investigation has brought new experimental evidence of a peripheral impact of central administration of H. gentili venom, such impact was manifested by physiological and behavioral disturbances, the last of these appearing to reflect profound neuro-modulatory action of H. gentili venom.

  11. Tris(pyrazolyl)phosphine oxide and Tris(triazolyl)phosphine oxide scorpion ligands

    NARCIS (Netherlands)

    Tazelaar, Cornelis G J; Lyaskovskyy, Volodymyr; Van Doorn, Ilana M.; Schaapkens, Xander; Lutz, Martin; Ehlers, Andreas W.; Slootweg, Jack; Lammertsma, Koop

    2014-01-01

    DFT calculations were performed on copper(I) complexes of neutral scorpion ligands based on either pyrazolyl (Pz) or triazolyl (Tz) rings with both methane and phosphine oxide apexes, that is, HC(Pz)3, OP(Pz)3, HC(Tz)3, and OP(Tz)3. The analyses reveal that all four ligands have similar donor proper

  12. Primary structure of the oligosaccharide moiety of hemocyanin from the scorpion Androctonus australis

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Debeire, P.; Montreuil, J.; Goyffon, M.; Kuik, J.A. van; Halbeek, H. van

    1986-01-01

    Hemocyanin, the copper-containing glycoprotein that serves as an oxygen carrier in the hemolymph of some arthropods and molluscs, was obtained from the blood of the scorpion Androctonus australis. Sugar analysis of the glycoprotein revealed that its carbohydrate moiety is of the N-glycosylic type. T

  13. Scorpion biodiversity and interslope divergence at "evolution canyon", lower Nahal Oren microsite, Mt. Carmel, Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Local natural laboratories, designated by us as the "Evolution Canyon" model, are excellent tools to study regional and global ecological dynamics across life. They present abiotic and biotic contrasts locally, permitting the pursuit of observations and experiments across diverse taxa sharing sharp microecological subdivisions. Higher solar radiation received by the "African savannah-like" south-facing slopes (AS in canyons north of the equator than by the opposite "European maquis-like" north-facing slopes (ES is associated with higher abiotic stress. Scorpions are a suitable taxon to study interslope biodiversity differences, associated with the differences in abiotic factors (climate, drought, due to their ability to adapt to dry environments. METHODOLOGY/PRINCIPAL FINDINGS: Scorpions were studied by the turning stone method and by UV light methods. The pattern observed in scorpions was contrasted with similar patterns in several other taxa at the same place. As expected, the AS proved to be significantly more speciose regarding scorpions, paralleling the interslope patterns in taxa such as lizards and snakes, butterflies (Rhopalocera, beetles (families Tenebrionidae, Dermestidae, Chrysomelidae, and grasshoppers (Orthoptera. CONCLUSIONS/SIGNIFICANCE: Our results support an earlier conclusion stating that the homogenizing effects of migration and stochasticity are not able to eliminate the interslope intra- and interspecific differences in biodiversity despite an interslope distance of only 100 m at the "EC" valley bottom. In our opinion, the interslope microclimate selection, driven mainly by differences in insolance, could be the primary factor responsible for the observed interslope pattern.

  14. Scorpion envenomation in pygmies from Democratic Republic of Congo, the example of Pelenge Center, Lomela, DRC

    Directory of Open Access Journals (Sweden)

    E Biezakala Mudiandambu

    2012-01-01

    Full Text Available In a survey among the pygmies of central Democratic Republic of Congo, the incidence of scorpion stings seemed very high with a severity greater than expected. Species responsible were not identified. Specific studies are needed to clarify the risk emerging in the equatorial African forest.

  15. Cardiac involvement and its complications about three cases of severe scorpion envenomation.

    Science.gov (United States)

    Aboumaâd, B; Tiger, A; Khattabi, A; Soulaymani, R; Lahssaini, M; Benhassain, S M; Iba, N

    2014-02-01

    For several decades, Morocco is confronted to medico-social problem of scorpion stings and envenomations. In 2009, epidemiological data established by the Poison Control Center recorded 29,816 stung patients, with an incidence of 1.1‰ and a fatality rate of 0.18%. The neurotoxins from scorpion venom are potent activators of the autonomic nervous system resulting a physiopathological disorder of vital systems. The most serious clinical manifestations are neurotoxic effects, pulmonary edema and cardiovascular distress. This present work reports the cases of three children (4 years and 6 months, 8 months and 15 days, 4 years), hospitalized in intensive care for an envenomation by Androctonus mauritanicus (the most fatal scorpion specie). The children presented cardiac dysfunction where pulmonary edema and state of shock were complications resultants. Two cases survived after supportive and symptomatic treatment based on dobutamine as primordial treatment in cardiovascular and pulmonary correction and other drugs. The third case died. The objective of this work was to detect the limit of the effectiveness of symptomatic treatment during a severe scorpion envenomation.

  16. Venom proteomic and venomous glands transcriptomic analysis of the Egyptian scorpion Scorpio maurus palmatus (Arachnida: Scorpionidae).

    Science.gov (United States)

    Abdel-Rahman, Mohamed A; Quintero-Hernandez, Veronica; Possani, Lourival D

    2013-11-01

    Proteomic analysis of the scorpion venom Scorpio maurus palmatus was performed using reverse-phase HPLC separation followed by mass spectrometry determination. Sixty five components were identified with molecular masses varying from 413 to 14,009 Da. The high percentage of peptides (41.5%) was from 3 to 5 KDa which may represent linear antimicrobial peptides and KScTxs. Also, 155 expressed sequence tags (ESTs) were analyzed through construction the cDNA library prepared from a pair of venomous gland. About 77% of the ESTs correspond to toxin-like peptides and proteins with definite open reading frames. The cDNA sequencing results also show the presence of sequences whose putative products have sequence similarity with antimicrobial peptides (24%), insecticidal toxins, β-NaScTxs, κ-KScTxs, α-KScTxs, calcines and La1-like peptides. Also, we have obtained 23 atypical types of venom molecules not recorded in other scorpion species. Moreover, 9% of the total ESTs revealed significant similarities with proteins involved in the cellular processes of these scorpion venomous glands. This is the first set of molecular masses and transcripts described from this species, in which various venom molecules have been identified. They belong to either known or unassigned types of scorpion venom peptides and proteins, and provide valuable information for evolutionary analysis and venomics.

  17. Genome-wide analysis of homeobox genes from Mesobuthus martensii reveals Hox gene duplication in scorpions.

    Science.gov (United States)

    Di, Zhiyong; Yu, Yao; Wu, Yingliang; Hao, Pei; He, Yawen; Zhao, Huabin; Li, Yixue; Zhao, Guoping; Li, Xuan; Li, Wenxin; Cao, Zhijian

    2015-06-01

    Homeobox genes belong to a large gene group, which encodes the famous DNA-binding homeodomain that plays a key role in development and cellular differentiation during embryogenesis in animals. Here, one hundred forty-nine homeobox genes were identified from the Asian scorpion, Mesobuthus martensii (Chelicerata: Arachnida: Scorpiones: Buthidae) based on our newly assembled genome sequence with approximately 248 × coverage. The identified homeobox genes were categorized into eight classes including 82 families: 67 ANTP class genes, 33 PRD genes, 11 LIM genes, five POU genes, six SINE genes, 14 TALE genes, five CUT genes, two ZF genes and six unclassified genes. Transcriptome data confirmed that more than half of the genes were expressed in adults. The homeobox gene diversity of the eight classes is similar to the previously analyzed Mandibulata arthropods. Interestingly, it is hypothesized that the scorpion M. martensii may have two Hox clusters. The first complete genome-wide analysis of homeobox genes in Chelicerata not only reveals the repertoire of scorpion, arachnid and chelicerate homeobox genes, but also shows some insights into the evolution of arthropod homeobox genes.

  18. Recovery of some of the missing wrappers of Berlese's Acari, Myriopoda et Scorpiones

    NARCIS (Netherlands)

    Hammen, van der L.

    1986-01-01

    Reproductions are given of the original wrappers of A. Berlese's Acari, Myriopoda et Scorpiones, fasc. II, IV, VI, VII and XIV. These wrappers (on some of which the first descriptions of new species are published) could not be included in the 1979 reprint edition of the work, as no extant copies of

  19. Antitoxin activity of plants used in Mexican traditional medicine against scorpion poisoning.

    Science.gov (United States)

    Jiménez-Ferrer, J E; Pérez-Terán, Y Y; Román-Ramos, R; Tortoriello, J

    2005-01-01

    Scorpions, especially in urban areas of tropical and subtropical regions, present a common risk of poisoning. In Mexico, scorpion envenomation is considered a public health problem. Despite the frequency of scorpion sting cases, there are to date no uniform criteria for their treatment. In Mexican traditional medicine, different plant species have been widely used as a remedy for treating scorpion poisoning. The aim of this work was to evaluate the effect of Bouvardia ternifolia, Aristolochia elegans and Vitex mollis extracts on Centruroides limpidus limpidus venom lethality in mice, and to determine their antagonist activity on guinea pig ileum. The hexane and methanol extract from B. ternifolia modified the LD50 of C. limpidus limpidus venom from 0.750 +/- 0.08 to 1.64 +/- 0.19 and 1.16 +/- 0.14 mg/kg, respectively. The extracts of A. elegans produced lower antitoxic activity, while extracts of V. mollis did not show any protection. On in vitro test, addition of B. ternifolia and A. elegans extracts strongly inhibited, in a concentration-dependent manner, the ileum contractions induced by venom. In general, the results demonstrated the effectiveness of these two plant species in modifying the lethality of C. limpidus limpidus venom in mice.

  20. Phospha-scorpionate complexes by click chemistry using phenyl azide and ethynylphosphine oxides

    NARCIS (Netherlands)

    van Assema, S.G.A.; Tazelaar, C.G.J.; de Jong, G.B.; van Maarseveen, J.H.; Schakel, M.; Lutz, M.; Spek, A.L.; Slootweg, J.C.; Lammertsma, K.

    2008-01-01

    The copper-catalyzed Click reaction of phenyl azide with ethynylphosphine oxides provides new P-substituted triazoles. With tris(ethynyl)phosphine oxide this route affords a versatile scorpionate ligand that coordinates to RhCl3 as a tripodal N ligand. Upon reduction, the same ligand can act as a P

  1. A single-point mutation enhances dual functionality of a scorpion toxin.

    Science.gov (United States)

    Wang, Xueli; Gao, Bin; Zhu, Shunyi

    2016-01-01

    Scorpion venom represents a tremendous, hitherto partially explored peptide library that has been proven to be useful not only for understanding ion channels but also for drug design. MeuTXKα3 is a functionally unknown scorpion toxin-like peptide. Here we describe new transcripts of this gene arising from alternative polyadenylation and its biological function as well as a mutant with a single-point substitution at site 30. Native-like MeuTXKα3 and its mutant were produced in Escherichia coli and their toxic function against Drosophila Shaker K(+) channel and its mammalian counterparts (rKv1.1-rKv1.3) were assayed by two-electrode voltage clamp technique. The results show that MeuTXKα3 is a weak toxin with a wide-spectrum of activity on both Drosophila and mammalian K(+) channels. The substitution of a proline at site 30 by an asparagine, an evolutionarily conserved functional residue in the scorpion α-KTx family, led to an increased activity on rKv1.2 and rKv1.3 but a decreased activity on the Shaker channel without changing the potency on rKv1.1, suggesting a key role of this site in species selectivity of scorpion toxins. MeuTXKα3 was also active on a variety of bacteria with lethal concentrations ranging from 4.66 to 52.01μM and the mutant even had stronger activity on some of these bacterial species. To the best of our knowledge, this is the first report on a bi-functional short-chain peptide in the lesser Asian scorpion venom. Further extensive mutations of MeuTXKα3 at site 30 could help improve its K(+) channel-blocking and antibacterial functions.

  2. Functional evolution of scorpion venom peptides with an inhibitor cystine knot fold.

    Science.gov (United States)

    Gao, Bin; Harvey, Peta J; Craik, David J; Ronjat, Michel; De Waard, Michel; Zhu, Shunyi

    2013-06-27

    The ICK (inhibitor cystine knot) defines a large superfamily of polypeptides with high structural stability and functional diversity. Here, we describe a new scorpion venom-derived K+ channel toxin (named λ-MeuKTx-1) with an ICK fold through gene cloning, chemical synthesis, nuclear magnetic resonance spectroscopy, Ca2+ release measurements and electrophysiological recordings. λ-MeuKTx-1 was found to adopt an ICK fold that contains a three-strand anti-parallel β-sheet and a 310-helix. Functionally, this peptide selectively inhibits the Drosophila Shaker K+ channel but is not capable of activating skeletal-type Ca2+ release channels/ryanodine receptors, which is remarkably different from the previously known scorpion venom ICK peptides. The removal of two C-terminal residues of λ-MeuKTx-1 led to the loss of the inhibitory activity on the channel, whereas the C-terminal amidation resulted in the emergence of activity on four mammalian K+ channels accompanied by the loss of activity on the Shaker channel. A combination of structural and pharmacological data allows the recognition of three putative functional sites involved in channel blockade of λ-MeuKTx-1. The presence of a functional dyad in λ-MeuKTx-1 supports functional convergence among scorpion venom peptides with different folds. Furthermore, similarities in precursor organization, exon-intron structure, 3D-fold and function suggest that scorpion venom ICK-type K+ channel inhibitors and Ca2+ release channel activators share a common ancestor and their divergence occurs after speciation between buthidae and non-buthids. The structural and functional characterizations of the first scorpion venom ICK toxin with K+ channel-blocking activity sheds light on functionally divergent and convergent evolution of this conserved scaffold of ancient origin.

  3. A RETROSPECTIVE STUDY OF EPIDEMIOLOGY CLINICAL COURSE AND TREATMENT OUTCOME OF SCORPION STING IN PAEDIATRIC AGE GROUP

    Directory of Open Access Journals (Sweden)

    Ramesh

    2015-12-01

    Full Text Available INTRODUCTION We know that habitat of scorpion is warm, and dry region. They inhibit commonly under logs, debris, paddy husk, sugar cane fields, and Coconut and banana plantations. (1 Konaseema region of Andhra Pradesh is famous for paddy, banana and coconut which are good habitat for scorpion. It is a retrospective study in which all the date of scorpion sting cases admitted in Konaseema institute of medical science and general hospital the only referral hospital in Konaseema region in last 3 years that is from Oct 2012 to Nov 2015 was collected. Mesobuthus tamulus is common in Andhra Pradesh. With the combined use of SAV and prazosin mortality has been reduced. But the awareness about the scorpion to the parent and its habitat will prevent the sting.

  4. Infective endocarditis and septic pulmonary embolism following scorpion sting envenoming in an 11-year-old child.

    Science.gov (United States)

    Prakash, Vellasamy; Krishnamurthy, Sriram; Mahadevan, Subramanian; Bethou, Adhisivam; Deepak Barathi, S

    2014-05-01

    Scorpion sting is one of the common paediatric toxicological problems encountered in southern India. This rural emergency often results in an autonomic storm causing peripheral circulatory failure and/or congestive cardiac failure, leading to pulmonary oedema. A rare case of scorpion sting envenoming in an 11-year-old boy that led to local cellulitis, dyspnoea and congestive heart failure is presented. This was followed by a persistent high-grade fever which lasted for more than 2 weeks and was complicated by fatal Staphylococcus aureus infective endocarditis and septic pulmonary embolism. Although infective endocarditis has been reported occasionally in adults following scorpion sting, this is the first case of infective endocarditis in a native valve in a child following scorpion sting. The literature is reviewed and the mechanisms for this association are discussed.

  5. New binding site on common molecular scaffold provides HERG channel specificity of scorpion toxin BeKm-1

    DEFF Research Database (Denmark)

    Korolkova, Yuliya V; Bocharov, Eduard V; Angelo, Kamilla

    2002-01-01

    The scorpion toxin BeKm-1 is unique among a variety of known short scorpion toxins affecting potassium channels in its selective action on ether-a-go-go-related gene (ERG)-type channels. BeKm-1 shares the common molecular scaffold with other short scorpion toxins. The toxin spatial structure...... resolved by NMR consists of a short alpha-helix and a triple-stranded antiparallel beta-sheet. By toxin mutagenesis study we identified the residues that are important for the binding of BeKm-1 to the human ERG K+ (HERG) channel. The most critical residues (Tyr-11, Lys-18, Arg-20, Lys-23) are located...... in the alpha-helix and following loop whereas the "traditional" functional site of other short scorpion toxins is formed by residues from the beta-sheet. Thus the unique location of the binding site of BeKm-1 provides its specificity toward the HERG channel....

  6. Anti-proliferation Effect of Polypeptide Extracted from Scorpion Venom on Human Prostate Cancer Cells in vitro

    OpenAIRE

    Zhang, Yue Ying; Wu, Li Cun; Wang, Zhao Peng; Wang, Zhao Xia; Jia, Qing; Jiang, Guo Sheng; Zhang, Wei Dong

    2009-01-01

    Background Prostate cancer is a major cause of cancer-related death in men. Therefore there has been considerable interest to explore neoadjuvant therapy. Polypeptide extracted from scorpion venom (PESV), originally obtained from the East-Asian scorpion Buthus martensi Karsch (BmK), is being studied for both prevention and treatment of various human malignancies including prostate cancer. Methods The present study was to investigate the effect of PESV on cell proliferation, cell cycle, and ap...

  7. The Effects of a Chactoid Scorpion Venom and Its Purified Toxins on Rat Blood Pressure and Mast Cells Histamine Release

    OpenAIRE

    2013-01-01

    The effect of the venom of the Chactoid family of scorpions on blood pressure was scantly investigated and was addressed in the present study using the venom of the Israeli scorpion, Scorpio maurus palmatus. Blood pressure in rats was monitored via cannulated femoral artery, while venom and toxins were introduced into femoral vein. Venom injection elicited a biphasic effect, expressed first by a fast and transient hypotensive response, which lasted up to 10 min, followed by a hypertensive res...

  8. Litter size, effects of maternal body size, and date of birth in South American scorpions (Arachnida: Scorpiones

    Directory of Open Access Journals (Sweden)

    Sabrina Outeda-Jorge

    2009-03-01

    Full Text Available We present new data on litter size and date of birth (month for 21 South American scorpions species. We provide data for one katoikogenic species, the liochelid Opisthacanthus cayaporum Vellard, 1932 (offspring = 3; birth month: Jan; and for several apoikogenic species, such as the bothriurids Bothriurus araguayae Vellard, 1934 (53; Sep, B. rochensis San Martín, 1965 (22-28; Jan, Aug; the buthids Ananteris balzanii Thorell, 1891 (10-34; Jan-Mar, Physoctonus debilis (Koch, 1840 (2; Sep, Rhopalurus amazonicus Lourenço, 1986 (19; Nov, R. lacrau Lourenço & Pinto-da-Rocha, 1997 (30; Dec, R. laticauda Thorell, 1876 (41; Nov, R. rochai Borelli, 1910 (11-47; Dec-Jan, Mar-Apr, Tityus bahiensis (Perty, 1833 (4-23; Oct-Mar, T. clathratus Koch, 1844 (8-18; Nov-Jan, T. costatus (Karsch, 1879 (21-25; Jan, Apr, T. kuryi Lourenço, 1997 (4-16; Mar, T. mattogrossensis Borelli, 1901(8-9; May, T. obscurus (Gervais, 1843 (16-31; Jan-Feb, May, Jul, T. serrulatus Lutz & Mello, 1922 (8-36; Dec, Feb-Apr, T. silvestris Pocock, 1897 (5-14; Dec-Jan, Apr, T. stigmurus (Thorell, 1876 (10-18; Nov, Jan, Mar, Tityus sp. 1 (T. clathratus group - 7-12; Feb-Apr, Tityus sp. 2 (T. bahiensis group - 2; Mar; and the chactid Brotheas sp. (8-21; Jan, Apr. We observed multiple broods: R. lacrau (offspring in the 2nd brood = 27, T. kuryi (6-16, T. obscurus (2-32, T. silvestris (8, T. stigmurus (4-9, T. bahiensis (offspring in the 2nd brood = 2-18; 3rd = 1, and T. costatus (2nd brood = 18; 3rd = 4. We found statistically significant positive correlation between female size and litter size for T. bahiensis and T. silvestris, and nonsignificant correlation for T. serrulatus.

  9. Nutrition of Scorpion and Application of Its Extracts%全蝎的营养成分及其提取物的应用

    Institute of Scientific and Technical Information of China (English)

    李志英; 孙中兴; 罗志强; 冯幼

    2012-01-01

    Scorpion is an animal which preys on mollusk insect. As a traditional Chinese herbal medicines, scorpion has potency of remove of blood stasis efficacy analgesic efficacy. This paper summarized the nutrition characteristic of scorpion and its application of scorpion extract.%蝎子是以软体昆虫为食的节肢动物。作为传统的中药材,全蝎具有熄风镇痉、攻毒散结、通络止痛的功效。文章就全蝎的营养成分及其提取物的应用作一简述。

  10. Investigating the chemical profile of regenerated scorpion (Parabuthus transvaalicus) venom in relation to metabolic cost and toxicity.

    Science.gov (United States)

    Nisani, Zia; Boskovic, Danilo S; Dunbar, Stephen G; Kelln, Wayne; Hayes, William K

    2012-09-01

    We investigated the biochemical profile of regenerated venom of the scorpion Parabuthus transvaalicus in relation to its metabolic cost and toxicity. Using a closed-system respirometer, we compared oxygen consumption between milked and unmilked scorpions to determine the metabolic costs associated with the first 192 h of subsequent venom synthesis. Milked scorpions had a substantially (21%) higher mean metabolic rate than unmilked scorpions, with the largest increases in oxygen consumption occurring at approximately 120 h, 162 h, and 186 h post-milking. Lethality tests in crickets indicated that toxicity of the regenerated venom returned to normal levels within 4 d after milking. However, the chemical profile of the regenerated venom, as evaluated by FPLC and MALDI-TOF mass spectrometry, suggested that regeneration of different venom components was asynchronous. Some peptides regenerated quickly, particularly those associated with the scorpion's "prevenom," whereas others required much or all of this time period for regeneration. This asynchrony could explain the different spikes detected in oxygen consumption of milked scorpions as various peptides and other venom components were resynthesized. These observations confirm the relatively high metabolic cost of venom regeneration and suggest that greater venom complexity can be associated with higher costs of venom production.

  11. Envenenamento por Tityus stigmurus (Scorpiones; Buthidae no Estado da Bahia, Brasil Envenomation by Tityus stigmurus (Scorpiones; Buthidae in Bahia, Brazil

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    Rejâne Maria Lira-da-Silva

    2000-06-01

    Full Text Available A presente investigação é um estudo descritivo dos aspectos clínicos dos acidentes causados pelo escorpião Tityus stigmurus no Estado da Bahia, Brasil. Foram analisados 237 casos confirmados, tratados pelo Centro de Informações Antiveneno da Bahia (CIAVE, no período de 1982-1995. O envenenamento por T. stigmurus caracterizou-se por manifestações locais: dor (94,4%, dormência (30%, edema (17,8%, eritema (17,8% e parestesia (15,6% e gerais: cefaléia (14%, vômitos (4,4% e sudorese (3,3%. A maioria dos envenenamentos (94% foi leve e todos evoluíram para cura. A ausência de letalidade, com o restabelecimento dos pacientes, inclusive casos graves, sugere a eficácia do tratamento com o antiveneno específico, apesar do veneno desta espécie não estar presente no pool de produção nacional do soro. Há necessidade de revisão dos critérios regionais nos esquemas atuais de soroterapia. Os dados apontam para a semelhança da gravidade do envenenamento por T. serrulatus, com exceção da ocorrência de óbitos e complicações sistêmicas.The present investigation is a descriptive study regarding the clinical aspects of accidents caused by the scorpion Tityus stigmurus in Bahia, Brazil. We analyzed 237 confirmed cases treated by the Antivenom Information Centre (CIAVE from 1982 to 1995. Envenomation by T. stigmurus was mainly characterized by local symptoms: pain (94.4%, dormancy (30.0%, edema (17.8%, erythema (17.8, paresthesia (15.6% and general manifestations such as headache (4.4%, vomiting (4.4% and sudoresis (3.3%. Most of the envenomation cases were mild (94% and all were successfully cured. Although T. stigmurus venom is not in the pool of anti-venom serum (SAE, the absence of lethality and benign nature of the cases suggest the efficiency of SAE. With the exception of deaths and systemic complications, envenoming gravity was similar to those of Tityus serrulatus.

  12. Natural occurrence of the Fusarium solani on Tityus stigmurus (Thorell, 1876 (Scorpiones: Buthidae

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    PL. Santana-Neto

    Full Text Available Members of the Fusarium solani species complex are agents of human mycoses, also affecting plants and other animals. Nevertheless, this fungus has not been reported on scorpions. Ten specimens of Tityus stigmurus collected in the field and showing their surface covered by white mycelia were used to assess fungus presence in the animal after its death. Identification of the fungi was based upon the cultural and morphological characteristics. The fungus was isolated from chelicerae and intersegmental regions. Infected individuals had their behaviour modified by reducing feeding and locomotion. None of the infected individuals survived. It is likely that this fungus may have a role in the regulation of field scorpion populations.

  13. Scorpion Venom Heat-Resistant Peptide Protects Transgenic Caenorhabditis elegans from β- Amyloid Toxicity

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    Xiao-Gang Zhang

    2016-07-01

    Full Text Available Scorpion venom heat-resistant peptide (SVHRP is a component purified from Buthus martensii Karsch scorpion venom. Our previous studies found SVHRP could enhance neurogenesis and inhibit microglia-mediated neuroinflammation in vivo. Here, we use the transgenic CL4176, CL2006 and CL2355 strains of Caenorhabditis elegans which express the human Aβ1–42 to investigate the effects and the possible mechanisms of SVHRP mediated protection against Aβ toxicity in vivo. The results showed that SVHRP-fed worms displayed remarkably decreased paralysis, less abundant toxic Aβ oligomers, reduced Aβ plaque deposition with respect to untreated animals. SVHRP also suppressed neuronal Aβ expression-induced defects in chemotaxis behavior and attenuated levels of ROS in the transgenic C. elegans. Taken together, these results suggest SVHRP could protect against Aβ-induced toxicity in C. elegans. Further studies need to be conducted in murine models and humans to analyze the effectiveness of the peptide.

  14. Scorpion Venom Heat-Resistant Peptide Protects Transgenic Caenorhabditis elegans from β-Amyloid Toxicity

    Science.gov (United States)

    Zhang, Xiao-Gang; Wang, Xi; Zhou, Ting-Ting; Wu, Xue-Fei; Peng, Yan; Zhang, Wan-Qin; Li, Shao; Zhao, Jie

    2016-01-01

    Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Our previous studies found SVHRP could enhance neurogenesis and inhibit microglia-mediated neuroinflammation in vivo. Here, we use the transgenic CL4176, CL2006, and CL2355 strains of Caenorhabditis elegans which express the human Aβ1-42 to investigate the effects and the possible mechanisms of SVHRP mediated protection against Aβ toxicity in vivo. The results showed that SVHRP-fed worms displayed remarkably decreased paralysis, less abundant toxic Aβ oligomers, reduced Aβ plaque deposition with respect to untreated animals. SVHRP also suppressed neuronal Aβ expression-induced defects in chemotaxis behavior and attenuated levels of ROS in the transgenic C. elegans. Taken together, these results suggest SVHRP could protect against Aβ-induced toxicity in C. elegans. Further studies need to be conducted in murine models and humans to analyze the effectiveness of the peptide. PMID:27507947

  15. Preparation of a polyvalent antivenom against various Mexican scorpion Centruroides species.

    Science.gov (United States)

    Garcia y Perez, G; Martin, M F; Rochat, H

    1988-01-01

    Antisera were obtained from rabbits injected with four different immunogens from the Mexican scorpion Centruroides suffusus suffusus i.e. the crude venom, a telson extract, a toxic fraction obtained from this telson extract by gel filtration and the same toxic fraction subjected to acetylation. The neutralizing capacity of these antisera are compared: it appears that a telson extract can be used instead of the crude venom to produce an efficient antiserum. The immunological properties of ground telsons obtained from three other species of the Mexican scorpion Centruroides (Centruroides noxius, Centruroides limpidus limpidus, Centruroides limpidus tecomanus) are studied with the antisera raised against Centruroides suffusus suffusus immunogens: an almost total cross-neutralization is observed.

  16. A K⁺ channel blocking peptide from the Cuban scorpion Rhopalurus garridoi.

    Science.gov (United States)

    Rodríguez-Ravelo, Rodolfo; Restano-Cassulini, Rita; Zamudio, Fernando Z; Coronas, Fredy I V; Espinosa-López, Georgina; Possani, Lourival D

    2014-03-01

    A proteomic analysis of the venom obtained from the Cuban scorpion Rhopalurus garridoi was performed. Venom was obtained by electrical stimulation, separated by high performance liquid chromatography, and the molecular masses of their 50 protein components were identified by mass spectrometry. A peptide of 3940 Da molecular mass was obtained in pure form and its primary structure determined. It contains 37 amino acid residues, including three disulfide bridges. Electrophysiological experiments showed that this peptide is capable of blocking reversibly K(+)-channels hKv1.1 with a Kd close to 1 μM, but is not effective against hKv1.4, hERG1 and EAG currents, at the same concentration. This is the first protein component ever isolated from this species of scorpion and was assigned the systematic number α-KTx 2.14.

  17. The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening.

    Science.gov (United States)

    Camargos, Thalita S; Bosmans, Frank; Rego, Solange C; Mourão, Caroline B F; Schwartz, Elisabeth F

    2015-01-01

    We identified Tf2, the first β-scorpion toxin from the venom of the Brazilian scorpion Tityus fasciolatus. Tf2 is identical to Tb2-II found in Tityus bahiensis. We found that Tf2 selectively activates human (h)Nav1.3, a neuronal voltage-gated sodium (Nav) subtype implicated in epilepsy and nociception. Tf2 shifts hNav1.3 activation voltage to more negative values, thereby opening the channel at resting membrane potentials. Seven other tested mammalian Nav channels (Nav1.1-1.2; Nav1.4-1.8) expressed in Xenopus oocytes are insensitive upon application of 1 μM Tf2. Therefore, the identification of Tf2 represents a unique addition to the repertoire of animal toxins that can be used to investigate Nav channel function.

  18. Insights into reproductive strategies of Tityus (Archaeotityus) pusillus Pocock, 1893 (Scorpiones, Buthidae).

    Science.gov (United States)

    de Albuquerque, Cleide Maria Ribeiro; de Araujo Lira, André Felipe

    2016-01-01

    A remarkable diversity of life history strategies has evolved among species for achieving reproductive success, including adaptive growth, protandry, iteroparity, and extra molting. Here, we report on the reproductive strategies of the litter-dwelling scorpion, Tityus (Archaeotityus) pusillus, the most abundant and widespread scorpion species in the Atlantic Forest of northeastern Brazil. We observed both iteroparity and protandry reproductive strategies in this species. Females were competent to produce up to three broods after a single insemination, and no correlation between female size and litter size was observed. Most males reached adulthood 1 month before females following four molts, characterizing protandry. Nevertheless, an extra molt was observed to occur in some males (n=4) and females (n=1). These findings highlight the life history traits of T. (A.) pusillus, which may imply in reproductive success and adaptation to changes in environmental conditions.

  19. Does scorpion bite lead to development of resistance to the effect of local anaesthetics?

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    Minnu Mridul Panditrao

    2012-01-01

    Full Text Available A patient posted for vaginal hysterectomy was administered subarachnoid block, which failed, so was repeated in one space above. The block failed again, after waiting for 30 min. Patient gave a history of scorpion bite twice, once at the age of 17 years on her right foot and again about 8 months back. Thereafter, balanced general anaesthesia was given. On eighth post-operative day, after explaining about her possible special condition (?Resistance to local anaesthetic agents, the patient was given left median, ulnar and radial nerve blocks at the wrist and local infiltration near the anatomical snuff box. There was neither sensory nor motor block. The scorpion venom is known to affect the pumping mechanism of sodium channels in the nerve fibres, which are involved in the mechanism of action of local anaesthetic drugs, it may be responsible for the development of ′resistance′ to the action of local anaesthetic agents.

  20. Epidemiological and clinical characteristics of scorpion stings in children in fez, Morocco

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    S Abourazzak

    2009-01-01

    Full Text Available Scorpion stings are a public health problem in Morocco, especially among children, who experience the most severe cases. Epidemiological and clinical findings on scorpion stings in Fez, Morocco, were evaluated in this investigation. Of 163 cases that required medical attention, 62.6% were male children. The mean age of patients was 4.8 ± 3.4 years. The mean time between stings and first medical attention was 3.36 ± 2.5 hours. Almost all cases occurred in the summer (94% and extremities represented the most frequent sting sites (86.5%. Local pain, hyperemia, scarification, vomiting, sweating, restlessness, tachycardia and tachypnea were the observed clinical symptoms. Regarding severity, 55.2% of patients belonged to class III, followed by class II (26.4% and class I (18.4%. None of our patients received antivenom; however, all of them were treated symptomatically depending on clinical manifestations.

  1. Biochemical and molecular characterization of the venom from the Cuban scorpion Rhopalurus junceus.

    Science.gov (United States)

    García-Gómez, B I; Coronas, F I V; Restano-Cassulini, R; Rodríguez, R R; Possani, L D

    2011-07-01

    This communication describes the first general biochemical, molecular and functional characterization of the venom from the Cuban blue scorpion Rhopalurus junceus, which is often used as a natural product for anti-cancer therapy in Cuba. The soluble venom of this arachnid is not toxic to mice, injected intraperitoneally at doses up to 200 μg/20 g body weight, but it is deadly to insects at doses of 10 μg per animal. The venom causes typical alpha and beta-effects on Na+ channels, when assayed using patch-clamp techniques in neuroblastoma cells in vitro. It also affects K+ currents conducted by ERG (ether-a-go-go related gene) channels. The soluble venom was shown to display phospholipase, hyaluronidase and anti-microbial activities. High performance liquid chromatography of the soluble venom can separate at least 50 components, among which are peptides lethal to crickets. Four such peptides were isolated to homogeneity and their molecular masses and N-terminal amino acid sequence were determined. The major component (RjAa12f) was fully sequenced by Edman degradation. It contains 64 amino acid residues and four disulfide bridges, similar to other known scorpion toxins. A cDNA library prepared from the venomous glands of one scorpion allowed cloning 18 genes that code for peptides of the venom, including RjA12f and eleven other closely related genes. Sequence analyses and phylogenetic reconstruction of the amino acid sequences deduced from the cloned genes showed that this scorpion contains sodium channel like toxin sequences clearly segregated into two monophyletic clusters. Considering the complex set of effects on Na+ currents verified here, this venom certainly warrant further investigation.

  2. A novel human recombinant antibody fragment capable of neutralizing Mexican scorpion toxins.

    Science.gov (United States)

    Riaño-Umbarila, Lidia; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Gurrola, Georgina B; Possani, Lourival D; Becerril, Baltazar

    2013-12-15

    Using phage display and directed evolution, our group has progressed in the construction of a second family of human single chain variable fragments (scFv) which bind to scorpion toxins dangerous to mammals. It was observed that scFv C1 only bound initially to toxin Cn2, which constitutes 6.8% of whole venom from the scorpion Centruroides noxius Hoffman. Only a few amino acid changes were necessary to extend its recognition to other similar toxins and without affecting the recognition for its primary antigen (Cn2 toxin). One variant of scFv C1 (scFv 202F) was selected after two cycles of directed evolution against Cll1 toxin, the second major toxic component from the venom of the Mexican scorpion Centruroides limpidus limpidus Karsh (0.5% of the whole venom). scFv 202F is also capable of recognizing Cn2 toxin. Despite not having the highest affinity for toxins Cll1 (KD = 25.1 × 10(-9) M) or Cn2 (KD = 8.1 × 10(-9) M), this antibody fragment neutralized one LD50 of each one of these toxins. Additionally, scFv 202F moderately recognized Cll2 toxin which constitutes 1.5% of the venom from C. limpidus. Based on our previous experience, we consider that these results are promising; consequently, we continue working on generating new optimized variants from scFv C1 that could be part of a recombinant scorpion anti-venom from human origin, that might reach the market in the near future.

  3. Partial Agonist and Antagonist Activities of a Mutant Scorpion β-Toxin on Sodium Channels*

    OpenAIRE

    Karbat, Izhar; Ilan, Nitza; Zhang, Joel Z.; Cohen, Lior; Kahn, Roy; Benveniste, Morris; Scheuer, Todd; Catterall, William A.; Gordon, Dalia; Gurevitz, Michael

    2010-01-01

    Scorpion β-toxin 4 from Centruroides suffusus suffusus (Css4) enhances the activation of voltage-gated sodium channels through a voltage sensor trapping mechanism by binding the activated state of the voltage sensor in domain II and stabilizing it in its activated conformation. Here we describe the antagonist and partial agonist properties of a mutant derivative of this toxin. Substitution of seven different amino acid residues for Glu15 in Css4 yielded toxin derivatives with both increased a...

  4. Inhibition of gastric emptying and intestinal transit in anesthetized rats by a Tityus serrulatus scorpion toxin

    Directory of Open Access Journals (Sweden)

    Troncon L.E.A.

    2000-01-01

    Full Text Available The effects of a fraction (T1 of Tityus serrulatus scorpion venom prepared by gel filtration on gastric emptying and small intestinal transit were investigated in male Wistar rats. Fasted animals were anesthetized with urethane, submitted to tracheal intubation and right jugular vein cannulation. Scorpion toxin (250 µg/kg or saline was injected iv and 1 h later a bolus of saline (1.0 ml/100 g labeled with 99m technetium-phytate (10 MBq was administered by gavage. After 15 min, animals were sacrificed and the radioactivity remaining in the stomach was determined. Intestinal transit was evaluated by instillation of a technetium-labeled saline bolus (1.0 ml through a cannula previously implanted in the duodenum. After 60 min, the progression of the marker throughout 7 consecutive gut segments was estimated by the geometric center method. Gastric retention of the liquid test meal in rats injected with scorpion toxin (median: 88%; range: 52-95% was significantly higher (P<0.02 than in controls (54%; 21-76%, an effect which was not modified by gastric secretion blockade with ranitidine. The progression of the isotope marker throughout the small intestine was significantly slower (P<0.05 in rats treated with toxin (1.2; 1.0-2.5 than in control animals (2.3; 1.0-3.2. Inhibition of both gastric emptying and intestinal transit in rats injected with scorpion toxin suggests an increased resistance to aboral flow, which might be caused by abnormal neurotransmitter release or by the local effects of venom on smooth muscle cells.

  5. Acute kidney injury in Hemiscorpius lepturus scorpion stung children: Risk factors and clinical features

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    Ehsan Valavi

    2016-01-01

    Full Text Available Acute kidney injury (AKI is frequently seen in Hemiscorpius lepturus scorpion stung children. We have previously reported several victims with hemolytic uremic syndrome (HUS and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 deficiency. Hence, we conducted this study to identify predictive factors and clinical features of AKI in H. lepturus scorpion stung patients. We included all 215 H. lepturus scorpion stung children with no previous renal diseases in two groups (with and without AKI and compared them based on their clinical and laboratory findings. AKI was found in 27.4% of patients, they were significantly younger and with lower body weight (P = 0.006, P = 0.011, respectively. There was a significant difference between groups with and without AKI in findings such as fever (P = 0.003, hypertension (P <0.001, hemolytic anemia (P <0.001, thrombocytopenia (P <0.001, massive proteinuria (P <0.001, hemoglobinuria (P <0.001, pyuria (P <0.001, and hematuria (P = 0.004. HUS was in 5.5% and disseminated intravascular coagulation in 14.6% which had a significant association with AKI (P <0.001.There were several independent predictors for AKI in a multivariate regression model including thrombocytopenia (P = 0.002, pyuria (P = 0.01, proteinuria (P =0.01, and fever (P = 0.02. Hemodialysis was performed in four patients but kidney function improved in all patients and there was no findings of renal impairment after three months follow-up. We found several predictors for AKI in children following H. lepturus scorpion sting including younger age, delay in receiving medical care, pigmenturia, microangiopathic hemolytic anemia, proteinuria, and pyuria.

  6. Assessment of myocardial perfusion and function in victims of scorpion envenomation using gated-SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Alexandre Baldini de; Cupo, Palmira; Pintya, Antonio O.; Caligaris, Fabio; Marin-Neto, Jose A; Hering, Sylvia E.; Simoes, Marcus Vinicius, E-mail: simoesmv@yahoo.co [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

    2010-04-15

    Background: cardiogenic shock and acute pulmonary edema are the major causes of death of patients with scorpion envenomation, whose pathophysiological mechanism remains controversial. Objective: to investigate the correlation between myocardial perfusion abnormalities and left ventricular contractile function in victims of scorpion envenomation. Methods: fifteen patients underwent ECG-gated myocardial perfusion scintigraphy (gated SPECT) within 72 hours of, and 15 days after scorpion envenomation. Images were analyzed by means of a semi-quantitative visual perfusion score (0 = normal, 4 = absent) and motion score (0 = normal, 4 akinesia), using the 17-segment model. Summed perfusion (SPS) and summed motion (SMS) scores were calculated for each patient. Ejection fraction (LVEF) was calculated by a commercially available software. Results: at baseline, 12 out of the 15 patients presented abnormal myocardial perfusion and contractility. Mean values of SPS, SMS and LVEF were 12.5 +- 7.3, 17.0 +- 12.8, and 44.6 +- 16.0%, respectively. A positive correlation between SPS and SMS (r = 0.68; p = 0.005) and negative correlation between SPS and LVEF (r -0.75; p = 0.0021) were found. The follow-up studies showed recovery of global contractility (LVEF of 68.9 +- 9.5, p = 0.0002), segmental contractility (SMS of 2.6 +- 3.1, p = 0.0009) and perfusion (SPS of 3.7 +- 3.3, p = 0.0003). Improvement of LVEF correlated positively with improvement of SPS (r = 0.72; p = 0.0035). Conclusions: myocardial perfusion abnormalities are common in scorpion envenomation and correlate topographically with the contractile dysfunction. Recovery of contractility correlates with reversibility of perfusion defects. These findings suggest the participation of myocardial perfusion abnormalities in the pathophysiology of this form of acute ventricular failure. (author)

  7. Technetium-99m labeling of tityustoxin and venom from the scorpion Tityus serrulatus

    Energy Technology Data Exchange (ETDEWEB)

    Nunan, E.A.; Cardoso, V.N.; Moraes-Santos, T. E-mail: tmoraes@dedalus.lcc.ufmg.br

    2002-12-01

    The tityustoxin, the most toxic fraction from scorpion Tityus serrulatus venom, has been used as a tool in several neurochemical and neuropharmacological studies. Biological activities of labeled and unlabeled tityustoxin and venom were compared. The samples were labeled in the presence of stannous chloride and sodium borohydride with a yield of 60-70% for the venom and 75-85% for tityustoxin and then chromatographed in Sephadex G-10. Biological activities of tityustoxin and venom were preserved after labeling.

  8. SdPI, the first functionally characterized Kunitz-type trypsin inhibitor from scorpion venom.

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    Ruiming Zhao

    Full Text Available BACKGROUND: Kunitz-type venom peptides have been isolated from a wide variety of venomous animals. They usually have protease inhibitory activity or potassium channel blocking activity, which by virtue of the effects on predator animals are essential for the survival of venomous animals. However, no Kunitz-type peptides from scorpion venom have been functionally characterized. PRINCIPAL FINDINGS: A new Kunitz-type venom peptide gene precursor, SdPI, was cloned and characterized from a venom gland cDNA library of the scorpion Lychas mucronatus. It codes for a signal peptide of 21 residues and a mature peptide of 59 residues. The mature SdPI peptide possesses a unique cysteine framework reticulated by three disulfide bridges, different from all reported Kunitz-type proteins. The recombinant SdPI peptide was functionally expressed. It showed trypsin inhibitory activity with high potency (K(i = 1.6×10(-7 M and thermostability. CONCLUSIONS: The results illustrated that SdPI is a potent and stable serine protease inhibitor. Further mutagenesis and molecular dynamics simulation revealed that SdPI possesses a serine protease inhibitory active site similar to other Kunitz-type venom peptides. To our knowledge, SdPI is the first functionally characterized Kunitz-type trypsin inhibitor derived from scorpion venom, and it represents a new class of Kunitz-type venom peptides.

  9. Screening of plants acting against Heterometrus laoticus scorpion venom activity on fibroblast cell lysis.

    Science.gov (United States)

    Uawonggul, Nunthawun; Chaveerach, Arunrat; Thammasirirak, Sompong; Arkaravichien, Tarinee; Chuachan, Chattong; Daduang, Sakda

    2006-01-16

    The aqueous extracts of 64 plant species, listed as animal- or insect-bite antidotes in old Thai drug recipes were screened for their activity against fibroblast cell lysis after Heterometrus laoticus scorpion venom treatment. The venom was preincubated with plant extract for 30 min and furthered treated to confluent fibroblast cells for 30 min. More than 40% efficiency (test/control) was obtained from cell treatment with venom preincubated with extracts of Andrographis paniculata Nees (Acanthaceae), Barringtonia acutangula (L.) Gaertn. (Lecythidaceae), Calamus sp. (Palmae), Clinacanthus nutans Lindau (Acanthaceae), Euphorbia neriifolia L. (Euphorbiaceae), Ipomoea aquatica Forssk (Convolvulaceae), Mesua ferrea L. (Guttiferae), Passiflora laurifolia L. (Passifloraceae), Plectranthus amboinicus (Lour.) Spreng. (Labiatae), Ricinus communis L. (Euphorbiaceae), Rumex sp. (Polygonaceae) and Sapindus rarak DC. (Sapindaceae), indicating that they had a tendency to be scorpion venom antidotes. However, only Andrographis paniculata and Barringtonia acutangula extracts provided around 50% viable cells from extract treatments without venom preincubation. These two plant extracts are expected to be scorpion venom antidotes with low cytotoxicity.

  10. Purification and chemical and biological characterizations of seven toxins from the Mexican scorpion, Centruroides suffusus suffusus.

    Science.gov (United States)

    Martin, M F; Garcia y Perez, L G; el Ayeb, M; Kopeyan, C; Bechis, G; Jover, E; Rochat, H

    1987-04-05

    Seven polypeptides highly toxic to mice were isolated from the venom of the scorpion, Centruroides suffusus suffusus (Css), and their chemical and toxic properties were characterized. It was shown that the most active toxins by intracerebroventricular injection are less active when injected subcutaneously. The complete amino acid sequence (66 residues) of toxin II (Css II) has been determined. The C-terminal end is amidated as found for most other scorpion toxins. Css II is a beta-type toxin, previously used to define the binding site for activation of the sodium channel. Using rat brain synaptosomes, we demonstrated that all Css toxins compete with 125I-Css II to bind to site 4 and should be considered as beta-scorpion toxins. Specific binding parameters for Css VI, one of the most active toxins, were determined: KD = 100 pM; capacity in binding sites, 2.2 pmol of toxin/mg of synaptosomal protein. Css VI was shown to inhibit gamma-aminobutyric acid uptake by synaptosomes: K 0.5 = 100 pM, which agrees with its KD. Competition experiments between the seven Css toxins and 125I-Css II for antiserum raised against Css II demonstrated that all these toxins have common antigenic properties.

  11. Location of 45S Ribosomal Genes in Mitotic and Meiotic Chromosomes of Buthid Scorpions.

    Science.gov (United States)

    Mattos, Viviane Fagundes; Carvalho, Leonardo Sousa; Cella, Doralice Maria; Schneider, Marielle Cristina

    2014-09-01

    Buthid scorpions exhibit a high variability in diploid number within genera and even within species. Cytogenetically, Buthidae differs from other families of Scorpiones based on its low diploid numbers, holocentric chromosomes, and complex chromosomal chains, which form during meiosis. In this study, we analyzed the distribution of the 45S ribosomal DNA (rDNA) genes in the mitotic and meiotic chromosomes of seven buthid species belonging to the genera Rhopalurus and Tityus with the ultimate goal of elucidating the chromosome organization in these scorpions. The chromosome number ranged from 2n=6 to 2n=28. Despite the high variance in diploid number, all species examined carried their 45S rDNA sites in the terminal region of exactly two chromosomes. Analyses of meiotic cells revealed 45S rDNA clusters in the chromosomal chains of Rhopalurus agamemnon, Tityus bahiensis, Tityus confluens, and Tityus martinpaechi, or in bivalent-like configuration in Rhopalurus rochai, Tityus bahiensis, Tityus confluens, Tityus fasciolatus, and Tityus paraguayensis. In the species examined, the 45S rDNA sites colocalized with constitutive heterochromatin regions. In light of the high chromosome variability and maintenance of number and terminal position of 45S rDNA sites in buthids, the heterochromatin may act to conserve the integrity of the ribosomal genes.

  12. Species delimitation and morphological divergence in the scorpion Centruroides vittatus (Say, 1821: insights from phylogeography.

    Directory of Open Access Journals (Sweden)

    Tsunemi Yamashita

    Full Text Available Scorpion systematics and taxonomy have recently shown a need for revision, partially due to insights from molecular techniques. Scorpion taxonomy has been difficult with morphological characters as disagreement exists among researchers with character choice for adequate species delimitation in taxonomic studies. Within the family Buthidae, species identification and delimitation is particularly difficult due to the morphological similarity among species and extensive intraspecific morphological diversity. The genus Centruroides in the western hemisphere is a prime example of the difficulty in untangling the taxonomic complexity within buthid scorpions. In this paper, we present phylogeographic, Ecological Niche Modeling, and morphometric analyses to further understand how population diversification may have produced morphological diversity in Centruroides vittatus (Say, 1821. We show that C. vittatus populations in the Big Bend and Trans-Pecos region of Texas, USA are phylogeographically distinct and may predate the Last Glacial Maximum (LGM. In addition, we suggest the extended isolation of Big Bend region populations may have created the C. vittatus variant once known as C. pantheriensis.

  13. Risk factors for scorpion stings in the beni mellal province of morocco

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    N Charrab

    2009-01-01

    Full Text Available Scorpion stings comprise a serious problem throughout the globe, especially in regions where they are more frequent. In Morocco, Beni Mellal is one of the provinces most affected by this burden. This study aimed to trace the epidemiological profile of scorpion stings in Beni Mellal in order to improve patient care and prevent both morbidity and mortality. Our work is a retrospective study of scorpion stings based on medical charts of Beni Mellal. From 2002 to 2007, 8,340 cases were registered in this province with an average incidence of 1.36‰. The stings were more frequent in summer months, particularly July and August, and between 6 p.m. and 6 a.m. (59.8%. The average age of victims was 26.54 ± 18.42 years. Children were affected in 30.3% of the cases. Of all registered cases, 67.3% of the patients received medical aid in less than an hour after the sting. The envenomation rate (Class II and Class III was 12.4% and the overall case-fatality rate was 0.42% with a mortality rate of 0.005‰. Statistical analysis of the various studied factors revealed a significant connection among the envenomation class, patient age and evolution.

  14. Variability in venom volume, flow rate and duration in defensive stings of five scorpion species.

    Science.gov (United States)

    van der Meijden, Arie; Coelho, Pedro; Rasko, Mykola

    2015-06-15

    Scorpions have been shown to control their venom usage in defensive encounters, depending on the perceived threat. Potentially, the venom amount that is injected could be controlled by reducing the flow speed, the flow duration, or both. We here investigated these variables by allowing scorpions to sting into an oil-filled chamber, and recording the accreting venom droplets with high-speed video. The size of the spherical droplets on the video can then be used to calculate their volume. We recorded defensive stings of 20 specimens representing 5 species. Significant differences in the flow rate and total expelled volume were found between species. These differences are likely due to differences in overall size between the species. Large variation in both venom flow speed and duration are described between stinging events of single individuals. Both venom flow rate and flow duration correlate highly with the total expelled volume, indicating that scorpions may control both variables in order to achieve a desired end volume of venom during a sting.

  15. Behavioral, histopathological and biochemical impairments observed in mice envenomed by the scorpion: Hottentota gentili (Pallary, 1924).

    Science.gov (United States)

    El Hidan, Moulay Abdelmonaim; Touloun, Oulaid; El Hiba, Omar; Chait, Abderrahman; Eddine Hafid, Jamal; Boumezzough, Ali

    2015-09-01

    Hottentota gentili is a black scorpion which has been considered as dangerous specie by many authors. However there are no data regarding minimal lethal dose and effects of the scorpion venom till now. We therefore aimed, by the present investigation, to assess on the one hand, the LD50 of H. gentili venom by sublethal injection and the effects on some vital organs, by a histological and a biochemical tools. On the other hand, the possible neurobehavioral impairments, in Swiss mice, 3 h, 6 h and 12 h following envenomation. The LD50 of H. gentili scorpion venom was found to be 0.46 mg/kg by subcutaneous injection route. Venom produced focal fragmentation of myocardial fibers, while lungs showed rupture of the alveolar structure. Intestines showed selective histopathological changes. Concomitantly, there was a significant rise in the serum enzymes levels, as well as hyperkalemia and a high level of plasma albumine and creatine. Proteinuria was also observed. The observed behavioral effects were a hypoactivity in the both experiments 30 min and 3 h after injection. The envenomation produced an increased immobility time only 30 min and 3 h post injection in the tail suspension test (TST).

  16. The transcriptome recipe for the venom cocktail of Tityus bahiensis scorpion.

    Science.gov (United States)

    de Oliveira, Ursula Castro; Candido, Denise Maria; Dorce, Valquíria Abrão Coronado; Junqueira-de-Azevedo, Inácio de Loiola Meirelles

    2015-03-01

    Scorpion venom is a mixture of peptides, including antimicrobial, bradykinin-potentiating and anionic peptides and small to medium proteins, such as ion channel toxins, metalloproteinases and phospholipases that together cause severe clinical manifestation. Tityus bahiensis is the second most medically important scorpion species in Brazil and it is widely distributed in the country with the exception of the North Region. Here we sequenced and analyzed the transcripts from the venom glands of T. bahiensis, aiming at identifying and annotating venom gland expressed genes. A total of 116,027 long reads were generated by pyrosequencing and assembled in 2891 isotigs. An annotation process identified transcripts by similarity to known toxins, revealing that putative venom components represent 7.4% of gene expression. The major toxins identified are potassium and sodium channel toxins, whereas metalloproteinases showed an unexpected high abundance. Phylogenetic analysis of deduced metalloproteinases from T. bahiensis and other scorpions revealed a pattern of ancient and intraspecific gene expansions. Other venom molecules identified include antimicrobial, anionic and bradykinin-potentiating peptides, besides several putative new venom components. This report provides the first attempt to massively identify the venom components of this species and constitutes one of the few transcriptomic efforts on the genus Tityus.

  17. New tricks of an old pattern: structural versatility of scorpion toxins with common cysteine spacing.

    Science.gov (United States)

    Saucedo, Alma Leticia; Flores-Solis, David; Rodríguez de la Vega, Ricardo C; Ramírez-Cordero, Belén; Hernández-López, Rogelio; Cano-Sánchez, Patricia; Noriega Navarro, Roxana; García-Valdés, Jesús; Coronas-Valderrama, Fredy; de Roodt, Adolfo; Brieba, Luis G; Domingos Possani, Lourival; del Río-Portilla, Federico

    2012-04-06

    Scorpion venoms are a rich source of K(+) channel-blocking peptides. For the most part, they are structurally related small disulfide-rich proteins containing a conserved pattern of six cysteines that is assumed to dictate their common three-dimensional folding. In the conventional pattern, two disulfide bridges connect an α-helical segment to the C-terminal strand of a double- or triple-stranded β-sheet, conforming a cystine-stabilized α/β scaffold (CSα/β). Here we show that two K(+) channel-blocking peptides from Tityus scorpions conserve the cysteine spacing of common scorpion venom peptides but display an unconventional disulfide pattern, accompanied by a complete rearrangement of the secondary structure topology into a CS helix-loop-helix fold. Sequence and structural comparisons of the peptides adopting this novel fold suggest that it would be a new elaboration of the widespread CSα/β scaffold, thus revealing an unexpected structural versatility of these small disulfide-rich proteins. Acknowledgment of such versatility is important to understand how venom structural complexity emerged on a limited number of molecular scaffolds.

  18. Scorpionism in Ecuador: First report of severe and fatal envenoming cases from northern Manabí by Tityus asthenes Pocock.

    Science.gov (United States)

    Borges, Adolfo; Morales, Melva; Loor, Wilmer; Delgado, Miguel

    2015-10-01

    The presence in rural areas of western Ecuador of scorpions in the genus Tityus capable of producing pediatric mortality is hereby evidenced. The medical significance of scorpions in Ecuador has been underestimated partly because of the clinically unimportant stings delivered by Centruroides margaritatus and Teuthraustes atramentarius, which have venom with low toxicity to vertebrates. Five intra-domiciliary cases of scorpion envenoming in victims aged between 1.9 and 16 years old, including one fatality, are reported from rural settings in forest areas of Chone (n = 2) and Flavio Alfaro (n = 3) counties, northern Manabí province, western Ecuador. Three cases were graded as Class II (moderate) and two in Class III (severe) envenoming. Manifestations showed characteristic autonomic nervous system hyper-stimulation and the fatality (a 1.9-year-old boy from Flavio Alfaro) was due to cardio-respiratory failure. Marked leukocytosis in four of the cases (21,800-31,800 cells/mm(3)), with notable neutrophilia (58-82%), suggests induction of a venom-mediated systemic inflammatory response-like syndrome. Specimens responsible for cases in Flavio Alfaro County, including the fatality, were classified as Tityus asthenes Pocock, accountable for severe scorpionism in Colombia. These findings demand implementation of control and therapeutic measures in affected areas in Ecuador, including evaluation of available scorpion antivenoms.

  19. Effect of Androctonus bicolor scorpion venom on serum electrolytes in rats: A 24-h time-course study.

    Science.gov (United States)

    Al-Asmari, A; Khan, H A; Manthiri, R A

    2016-03-01

    Black fat-tailed scorpion (Androctonus bicolor) belongs to the family Buthidae and is one of the most venomous scorpions in the world. The effects of A. bicolor venom on serum electrolytes were not known and therefore investigated in this study. Adult male Wistar rats were randomly divided into seven groups with five animals in each group. One of the groups served as control and received vehicle only. The animals in the remaining groups received a single subcutaneous injection of crude A. bicolor venom (200 μg/kg bodyweight) and were killed at different time intervals including 30 min, 1 h, 2 h, 4 h, 8 h, and 24 h after venom injection. The results showed that scorpion venom caused significant increase in serum sodium levels within 30 min after injection which slightly subsided after 1 h and then persisted over 24 h. Serum potassium levels continued to significantly increase until 4 h and then slightly subsided. There were significant decreases in serum magnesium (Mg(+)) levels following scorpion venom injection, at all the time points during the course of study. Serum calcium levels were significantly increased during the entire course of study, whereas serum chloride was significantly decreased. In conclusion, A. bicolor envenomation in rats caused severe and persistent hypomagnesemia with accompanied hypernatremia, hyperkalemia, and hypercalcemia. It is important to measure serum Mg(+) levels in victims of scorpion envenomation, and patients with severe Mg(+) deficiency should be treated accordingly.

  20. Two non-coding transcripts of toxins from the scorpion But-hus martensii Karsch: Evi-dence for the existence of NMD in scorpion venom gland cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Two non-coding transcripts of toxins were isolated from the venom gland Cdna library of the Chinese scorpion Buthus martensii Karsch, named BmβTX15-SP and BmTXKβ-SP, respectively. Analysis of nucleotide sequences shows that their 5′ sequences are identical to the 5′UTR and upstream open reading frame (ORF) sequences of the cDNAs encoding BmβTX15 and BmTXKβ, two toxins from Buthus martensii Karsch. But no detectable homology exists in other regions. Two polyadenylated non-coding transcripts encode multiple short ORFs with no more than 34 amino acid residues. The tailing signal (AATAAA) is situated at 14 or 18 bp downstream from the poly(A). The data of genomic sequences provides support for Bmβ TX15-SP and BmTXK β-SP not deriving from splicing errors of pre- mRNAs. Our finding provides evidence for the existence of nonsense-mediated Mrna decay (NMD) pathway in scorpion venom gland cells.

  1. Functional and immuno-reactive characterization of a previously undescribed peptide from the venom of the scorpion Centruroides limpidus.

    Science.gov (United States)

    Olamendi-Portugal, Timoteo; Restano-Cassulini, Rita; Riaño-Umbarila, Lidia; Becerril, Baltazar; Possani, Lourival D

    2017-01-01

    A previously undescribed toxic peptide named Cl13 was purified from the venom of the Mexican scorpion Centruroides limpidus. It contains 66 amino acid residues, including four disulfide bonds. The physiological effects assayed in 7 different subtypes of voltage gated Na(+)-channels, showed that it belongs to the β-scorpion toxin type. The most notorious effects were observed in subtypes Nav1.4, Nav1.5 and Nav1.6. Although having important sequence similarities with two other lethal toxins from this scorpion species (Cll1m and Cll2), the recently developed single chain antibody fragments (scFv) of human origin were not capable of protecting against Cl13. At the amino acid sequence level, in 3 stretches of peptide Cl13 (positions 7-9, 30-38 and 62-66) some differences with respect to other similar toxins are observed. Some of these differences coincide with contact points with the human antibody fragments.

  2. Structure and function of the voltage sensor of sodium channels probed by a beta-scorpion toxin.

    Science.gov (United States)

    Cestèle, Sandrine; Yarov-Yarovoy, Vladimir; Qu, Yusheng; Sampieri, François; Scheuer, Todd; Catterall, William A

    2006-07-28

    Voltage sensing by voltage-gated sodium channels determines the electrical excitability of cells, but the molecular mechanism is unknown. beta-Scorpion toxins bind specifically to neurotoxin receptor site 4 and induce a negative shift in the voltage dependence of activation through a voltage sensor-trapping mechanism. Kinetic analysis showed that beta-scorpion toxin binds to the resting state, and subsequently the bound toxin traps the voltage sensor in the activated state in a voltage-dependent but concentration-independent manner. The rate of voltage sensor trapping can be fit by a two-step model, in which the first step is voltage-dependent and correlates with the outward gating movement of the IIS4 segment, whereas the second step is voltage-independent and results in shifted voltage dependence of activation of the channel. Mutations of Glu(779) in extracellular loop IIS1-S2 and both Glu(837) and Leu(840) in extracellular loop IIS3-S4 reduce the binding affinity of beta-scorpion toxin. Mutations of positively charged and hydrophobic amino acid residues in the IIS4 segment do not affect beta-scorpion toxin binding but alter voltage dependence of activation and enhance beta-scorpion toxin action. Structural modeling with the Rosetta algorithm yielded a three-dimensional model of the toxin-receptor complex with the IIS4 voltage sensor at the extracellular surface. Our results provide mechanistic and structural insight into the voltage sensor-trapping mode of scorpion toxin action, define the position of the voltage sensor in the resting state of the sodium channel, and favor voltage-sensing models in which the S4 segment spans the membrane in both resting and activated states.

  3. Structure and Function of the Voltage Sensor of Sodium Channels Probed by a β-Scorpion Toxin*S

    Science.gov (United States)

    Cestèle, Sandrine; Yarov-Yarovoy, Vladimir; Qu, Yusheng; Sampieri, François; Scheuer, Todd; Catterall, William A.

    2006-01-01

    Voltage sensing by voltage-gated sodium channels determines the electrical excitability of cells, but the molecular mechanism is unknown. β-Scorpion toxins bind specifically to neurotoxin receptor site 4 and induce a negative shift in the voltage dependence of activation through a voltage sensor-trapping mechanism. Kinetic analysis showed that β-scorpion toxin binds to the resting state, and subsequently the bound toxin traps the voltage sensor in the activated state in a voltage-dependent but concentration-independent manner. The rate of voltage sensor trapping can be fit by a two-step model, in which the first step is voltage-dependent and correlates with the outward gating movement of the IIS4 segment, whereas the second step is voltage-independent and results in shifted voltage dependence of activation of the channel. Mutations of Glu779 in extracellular loop IIS1–S2 and both Glu837 and Leu840 in extracellular loop IIS3–S4 reduce the binding affinity of β-scorpion toxin. Mutations of positively charged and hydrophobic amino acid residues in the IIS4 segment do not affect β-scorpion toxin binding but alter voltage dependence of activation and enhance β-scorpion toxin action. Structural modeling with the Rosetta algorithm yielded a three-dimensional model of the toxin-receptor complex with the IIS4 voltage sensor at the extracellular surface. Our results provide mechanistic and structural insight into the voltage sensor-trapping mode of scorpion toxin action, define the position of the voltage sensor in the resting state of the sodium channel, and favor voltage-sensing models in which the S4 segment spans the membrane in both resting and activated states. PMID:16679310

  4. Antiserum production in immunized camel by the venom of Hemiscorpius lepturus scorpion: evaluation of neutralizing test in vivo

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    Behdani M

    2010-08-01

    Full Text Available "nBackground: Scorpion envenomation is considered as one of the Public Health problems in some countries in the world including Iran. Annually, approximately 30,000 scorpion stings happen in Iran from which 12% belongs to Hemiscorpius lepturus (special small closely spaced, bead-shaped jointed tail, similar in the shape to a cows tail, and is locally called ‘‘gaodim'' (Gao, cow; dim, tail with 95% mortality. The main treatment is antiserum therapy which is produced in horse and is the only way to neutralize the venom. Due to the anaphylactic shock of the horse antiserum in some of the stung patients other source of antiserum is recommended. In this study the ability of produced camel antiserum in neutralizing the scorpion venom of Hemiscorpius lepturus was performed in Balb/c model. "n"nMethods: Camel is an animal model that genetically is compatible with human genome utilized in this research to produce antiserum against scorpion venom. Two camels were used for immunization with the venom of Hemiscorpius lepturus. ELISA method was used to confirm the immunity. Antiserum was produced and used for neutralizing test. The precipitated antiserum with saturated ammonium sulfate (SAS was also used to perform the neutralizing test in mice. "n"nResults: The results indicated that the amount of 200 µl of antiserum and 400 µl of SAS antiserum were able to neutralize the amount of 1 LD100 of the venom and the survived the mice from death. "n"nConclusion: The result indicated that camel antiserum against scorpion venom is capable to neutralize the crude venom in mice model. Due to the safety of camel serum in human, it is suggested that the produced antiserum in camel can be substitute with the traditional horse antiserum in scorpion stung patients.

  5. Interventional effect of scorpion venom from Buthus martensii Karsch in Liaoning on somatic pain

    Institute of Scientific and Technical Information of China (English)

    Xinxin Li; Fengzhi Cui

    2006-01-01

    BACKGROUND: Scorpion venom from Buthus martensii Karsch is a kind of protein toxin secreted by scorpion tail. According to records of Pen-ts'ao Kan-mu, the dried scorpion's body and tail are used as medicine,which mainly treating rheumatism numbness, pain and convulsion. Some researches consider that scorpion toxin is the main pharmacological active component of the dried scorpion, and it has 4 times stronger analgesic effect on somatic pain than morphine.OBJECTIVE: To observe the interventional effect of scorpion venom of Buthus martensii Karsch analgesic active peptide on somatic pain.DESIGN: A randomized and controlled trial.SETTING: Department of Physiology, Shenyang Medical College.MATERIALS: Totally 80 Wistar rats (provided by Animal Center of Shenyang Medical College), male and female in half, aged 3 to 4 months, weighed 250 to 350 g, were used in this trial. They were randomly divided into 4 groups: experimental group, control group, morphine group and naloxone group, with 20 in each group. Analgesia active peptide from buthus martensii karsch venom (provided by Biochemical Department of Shenyang Pharmaceutical University, 1 mL/dosage), morphine (produced by Shanghai First Pharmaceutical Manufacturing Plant), naloxone (opium acceptor inhibitor, American Sigma Corporation), AT-AC-350 data-processing machine (Nihon Kohden Corporation), X-Y recording instrument (Nihon Kohden Corporation).METHODS: The experiment was conducted in the Department of Physiology, Shenyang Medical College from July 2003 to July 2005. ① After all the animals were anesthetized, common peroneal nerve is dissected and ligated at middle part. Posterior nucleus group of thalamus (PO) and the tail nuclear were oriented according to G. Paxino rat brain three-dimensional orientation atlas. Glass micro electrode was inserted into PO as guiding electrode, connected with ATAC-350 data-processing machine and X-Y recording instrument,to record the unit evoked potential of PO, taking the evoked

  6. Circumstantial evidences for mimicry of scorpions by the neotropical gecko Coleodactylus brachystoma (Squamata, Gekkonidae in the Cerrados of central Brazil

    Directory of Open Access Journals (Sweden)

    Reuber Albuquerque Brandão

    2005-12-01

    Full Text Available There are few records of invertebrates mimicry by reptiles. In the Cerrados of central Brazil, the small Coleodactylus brachystoma is an endemic species common in the islands and margins of the Serra da Mesa hydroelectric dam reservoir. When cornered, this lizard folds the tail over the body exposing the pale-orange ventral surface. Lizard behavior, tail length and color pattern confer to this lizard a strong resemblance with syntopic buthid scorpions Rhopalurus agamenon, Tytius matogrossensis, and Anantheris balzani. Lizards and scorpions share the same tail color, size, and shape. Ecologically, they use the same microhabitats, are exposed to the same potential predators, and present similar behaviors when threatened.

  7. Solution structure of Pi4, a short four-disulfide-bridged scorpion toxin specific of potassium channels.

    OpenAIRE

    Guijarro, J. Iñaki; M'Barek, Sarrah; Gómez-Lagunas, Froylan; Garnier, Damien; Rochat, Hervé; Sabatier, Jean-Marc; Possani, Lourival; Delepierre, Muriel; Possani, Lourrival

    2003-01-01

    Pi4 is a short toxin found at very low abundance in the venom of Pandinus imperator scorpions. It is a potent blocker of K(+) channels. Like the other members of the alpha-KTX6 subfamily to which it belongs, it is cross-linked by four disulfide bonds. The synthetic analog (sPi4) and the natural toxin (nPi4) have been obtained by solid-phase synthesis or from scorpion venom, respectively. Analysis of two-dimensional (1)H NMR spectra of nPi4 and sPi4 indicates that both peptides have the same s...

  8. Accident caused by Centruroides testaceus (DeGeer, 1778 (Scorpiones, Buthidae, native to the Caribbean, in Brazilian airport

    Directory of Open Access Journals (Sweden)

    Ricardo Antônio Lobo

    2011-12-01

    Full Text Available Describes the case of a 6-year-old girl who was stung by a Centruroides testaceus, a scorpion native to the Lesser Antilles, in the Guarulhos International Airport, São Paulo, Brazil, as she disembarked from a flight coming from the Caribbean. The patient presented only local symptoms (a small area of erythema and pain at the sting site, which were resolved after a few hours with analgesics, without the need for antivenom. Physicians who treat patients stung by scorpions should be alert to the possibility of such accidents being caused by non native species, especially those cases that occur near airports or ports.

  9. Effects of antigliomatin from the scorpion venom of Buthus martensii Karsch on chloride channels on C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Zan Wang; Mingxian Li; Hongmei Meng; Min Huang; Weihong Lin; Li Cui; Shao Wang

    2011-01-01

    Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensii Karsch. Chloride channels are closed under normal osmotic pressure. When osmotic pressure was reduced to 120, 110 and 100 mV, the cell volume enlarged, chloride channels opened, and the chloride channel current increased. Three minutes after antigliomatin treatment, the chloride channel current decreased in a dose-dependent manner. These results show that antigliomatin extracted from the venom of the scorpion Buthus martensii Karsch diminishes chloride channel currents on C6 glioma cells.

  10. Anti-HIV-1 activity of a new scorpion venom peptide derivative Kn2-7.

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    Yaoqing Chen

    Full Text Available For over 30 years, HIV/AIDS has wreaked havoc in the world. In the absence of an effective vaccine for HIV, development of new anti-HIV agents is urgently needed. We previously identified the antiviral activities of the scorpion-venom-peptide-derived mucroporin-M1 for three RNA viruses (measles viruses, SARS-CoV, and H5N1. In this investigation, a panel of scorpion venom peptides and their derivatives were designed and chosen for assessment of their anti-HIV activities. A new scorpion venom peptide derivative Kn2-7 was identified as the most potent anti-HIV-1 peptide by screening assays with an EC(50 value of 2.76 µg/ml (1.65 µM and showed low cytotoxicity to host cells with a selective index (SI of 13.93. Kn2-7 could inhibit all members of a standard reference panel of HIV-1 subtype B pseudotyped virus (PV with CCR5-tropic and CXCR4-tropic NL4-3 PV strain. Furthermore, it also inhibited a CXCR4-tropic replication-competent strain of HIV-1 subtype B virus. Binding assay of Kn2-7 to HIV-1 PV by Octet Red system suggested the anti-HIV-1 activity was correlated with a direct interaction between Kn2-7 and HIV-1 envelope. These results demonstrated that peptide Kn2-7 could inhibit HIV-1 by direct interaction with viral particle and may become a promising candidate compound for further development of microbicide against HIV-1.

  11. A Scorpion Defensin BmKDfsin4 Inhibits Hepatitis B Virus Replication in Vitro

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    Zhengyang Zeng

    2016-04-01

    Full Text Available Hepatitis B virus (HBV infection is a major worldwide health problem which can cause acute and chronic hepatitis and can significantly increase the risk of liver cirrhosis and primary hepatocellular carcinoma (HCC. Nowadays, clinical therapies of HBV infection still mainly rely on nucleotide analogs and interferons, the usage of which is limited by drug-resistant mutation or side effects. Defensins had been reported to effectively inhibit the proliferation of bacteria, fungi, parasites and viruses. Here, we screened the anti-HBV activity of 25 scorpion-derived peptides most recently characterized by our group. Through evaluating anti-HBV activity and cytotoxicity, we found that BmKDfsin4, a scorpion defensin with antibacterial and Kv1.3-blocking activities, has a comparable high inhibitory rate of both HBeAg and HBsAg in HepG2.2.15 culture medium and low cytotoxicity to HepG2.2.15. Then, our experimental results further showed that BmKDfsin4 can dose-dependently decrease the production of HBV DNA and HBV viral proteins in both culture medium and cell lysate. Interestingly, BmKDfsin4 exerted high serum stability. Together, this study indicates that the scorpion defensin BmKDfsin4 also has inhibitory activity against HBV replication along with its antibacterial and potassium ion channel Kv1.3-blocking activities, which shows that BmKDfsin4 is a uniquely multifunctional defensin molecule. Our work also provides a good molecule material which will be used to investigate the link or relationship of its antiviral, antibacterial and ion channel–modulating activities in the future.

  12. A Scorpion Defensin BmKDfsin4 Inhibits Hepatitis B Virus Replication in Vitro

    Science.gov (United States)

    Zeng, Zhengyang; Zhang, Qian; Hong, Wei; Xie, Yingqiu; Liu, Yun; Li, Wenxin; Wu, Yingliang; Cao, Zhijian

    2016-01-01

    Hepatitis B virus (HBV) infection is a major worldwide health problem which can cause acute and chronic hepatitis and can significantly increase the risk of liver cirrhosis and primary hepatocellular carcinoma (HCC). Nowadays, clinical therapies of HBV infection still mainly rely on nucleotide analogs and interferons, the usage of which is limited by drug-resistant mutation or side effects. Defensins had been reported to effectively inhibit the proliferation of bacteria, fungi, parasites and viruses. Here, we screened the anti-HBV activity of 25 scorpion-derived peptides most recently characterized by our group. Through evaluating anti-HBV activity and cytotoxicity, we found that BmKDfsin4, a scorpion defensin with antibacterial and Kv1.3-blocking activities, has a comparable high inhibitory rate of both HBeAg and HBsAg in HepG2.2.15 culture medium and low cytotoxicity to HepG2.2.15. Then, our experimental results further showed that BmKDfsin4 can dose-dependently decrease the production of HBV DNA and HBV viral proteins in both culture medium and cell lysate. Interestingly, BmKDfsin4 exerted high serum stability. Together, this study indicates that the scorpion defensin BmKDfsin4 also has inhibitory activity against HBV replication along with its antibacterial and potassium ion channel Kv1.3-blocking activities, which shows that BmKDfsin4 is a uniquely multifunctional defensin molecule. Our work also provides a good molecule material which will be used to investigate the link or relationship of its antiviral, antibacterial and ion channel–modulating activities in the future. PMID:27128943

  13. Impact of scorpion venom as an acute stressor on the neuroendocrine-immunological network.

    Science.gov (United States)

    Santhosh, K N; Pavana, D; Thippeswamy, N B

    2016-11-01

    Although immunomodulatory property and many other pharmaceutical applications of scorpion venom have been addressed before, no studies were reported about its application as a neuroimmunomodulator at therapeutic dose. In this study, we conceptualized the property of scorpion venom, capable of inducing the acute pain and neurotoxicity can cause acute stress resulting in the modulation of immune cells through HPA axis. The whole venom from Hottentotta rugiscutis, a widely seen scorpion in the region of eastern Karnataka, was extracted and injected a single dose of 1 mg/kg b.w. to Swiss albino mice and then erythrocytes and leukogram were measured. Whole brain AChE activity, corticosterone, cytokines and NO levels in plasma were also evaluated at various time points. Hrv didn't show any histopathological changes in the lymphoid organs and at the site of injection. However, lymphocytes and neutrophils did get altered at 2 h post-injection. Plasma corticosterone, cytokine levels such as IL-1β, IL-6, TNF-α and IL-10 and the AChE activity were significantly increased in a time-dependent manner. Based on these results, it may be predicted, Hrv's ability to cause acute stress resulted in the activation of HPA axis, which stimulates the release of glucocorticoid hormones which in turn elicits the immunomodulation of leukocytes by altering the levels of pro and anti-inflammatory cytokines. Thus, we can conclude, the impact of acute stress induced by Hrv can intercommunicate the signals between neuroendocrine-immune systems.

  14. Selected scorpion toxin exposures induce cytokine release in human peripheral blood mononuclear cells.

    Science.gov (United States)

    Corzo, Gerardo; Espino-Solis, Gerardo Pavel

    2017-03-01

    A cytokine screening on human peripheral blood mononuclear cells (PBMCs) stimulated with selected scorpion toxins (ScTx's) was performed in order to evaluate their effect on human immune cells. The ScTx's chosen for this report were three typical buthid scorpion venom peptides, one with lethal effects on mammals Centruroides suffussus suffusus toxin II (CssII), another, with lethal effects on insects and crustaceans Centruroides noxius toxin 5 (Cn5), and one more without lethal effects Tityus discrepans toxin (Discrepin). A Luminex multiplex analysis was performed in order to determine the amounts chemokines and cytokines IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12-p40, IL-13, interferon alpha (IFN-α), interferon gamma (IFN-γ), tumor necrosis factor alpha TNF-α, and interferon-inducible protein-10 (IP-10) secreted from human PBMCs exposed to these toxins. Although, the ScTx Cn5 is not lethal for mammals, it was able to induce the secretion of cytokines IL-1β, IL-6, and TNF-α, IL-10 and IP-10 in comparison to the lethal CssII, which was able to induce only IP-10 secretion. Discrepin also was able to induce only IP-10. Interestingly, only low amounts of interferons α and β were induced in the presence of the ScTx's assayed. In a synergic experiment, the combination of Discrepin and Cn5 displayed considerable reverse effects on induction of IL-1β, IL-6, IL-10 and TNF-α, but they had a slight synergic effect on IP-10 cytokine production in comparison with the single effect obtained with the Cn5 alone. Thus, the results obtained suggest that the profile of secreted cytokines promoted by ScTx Cn5 is highly related with a cytokine storm event, and also it suggests that the mammalian lethal neurotoxins are not solely responsible of the scorpion envenomation symptomatology.

  15. Neurological effects of venomous bites and stings: snakes, spiders, and scorpions.

    Science.gov (United States)

    Del Brutto, Oscar H

    2013-01-01

    Snake and spider bites, as well as scorpion sting envenoming, are neglected diseases affecting millions of people all over the world. Neurological complications vary according to the offending animal, and are often directly related to toxic effects of the venom, affecting the central nervous system, the neuromuscular transmission, the cardiovascular system, or the coagulation cascade. Snake bite envenoming may result in stroke or muscle paralysis. Metalloproteinases and other substances (common in vipers and colubrids) have anticoagulant or procoagulant activity, and may induce ischemic or hemorrhagic strokes. The venom of elapids is rich in neurotoxins affecting the neuromuscular transmission at either presynaptic or postsynaptic levels. The clinical picture of scorpion sting envenoming is dominated by muscle weakness associated with arterial hypertension, cardiac arrythmias, myocarditis, or pulmonary edema. These manifestations occur as the result of release of catecholamines into the bloodstream or due to direct cardiac toxicity of the venom. Cerebrovascular complications have been reported after the sting of the Indian red scorpion. Intracranial hemorrhages occur in the setting of acute increases in arterial blood pressure related to sympathetic overstimulation, and cerebral infarctions are related to either cerebral hypoperfusion, consumption coagulopathy, vasculitis, or cardiogenic brain embolism. Three main syndromes result from spider bite envenoming: latrodectism, loxoscelism, and funnel-web spider envenoming. Latrodectism is related to neurotoxins present in the venom of widow spiders. Most cases present with headache, lethargy, irritability, myalgia, tremor, fasciculation, or ataxia. Loxoscelism is caused by envenoming by spiders of the family Sicariidae. It may present with a stroke due to a severe coagulopathy. The venom of funnel-web spiders also has neurotoxins that stimulate neurotransmitter release, resulting in sensory disturbances and muscle

  16. Immunopathologic effects of scorpion venom on hepato-renal tissues: Involvement of lipid derived inflammatory mediators.

    Science.gov (United States)

    Lamraoui, Amal; Adi-Bessalem, Sonia; Laraba-Djebari, Fatima

    2015-10-01

    Scorpion venoms are known to cause different inflammatory disorders through complex mechanisms in various tissues. In the study here, the involvement of phospholipase A2 (PLA2) and cyclo-oxygenase (COX)-derived metabolites in hepatic and renal inflammation responses were examined. Mice were envenomed with Androctonus australis hector scorpion venom in the absence or presence of inhibitors that can interfere with lipid inflammatory mediator synthesis, i.e., dexamethasone (PLA2 inhibitor), indomethacin (non-selective COX-1/COX-2 inhibitor), or celecoxib (selective COX-2 inhibitor). The inflammatory response was assessed by evaluating vascular permeability changes, inflammatory cell infiltration, oxidative/nitrosative stress marker levels, and by histologic and functional analyses of the liver and kidney. Results revealed that the venom alone induced an inflammatory response in this tissues marked by increased microvascular permeability and inflammatory cell infiltration, increases in levels of nitric oxide and lipid peroxidation, and decreases in antioxidant defense. Moreover, significant alterations in the histological architecture of these organs were associated with increased serum levels of some metabolic enzymes, as well as urea and uric acid. Pre-treatment of mice with dexamethasone led to significant decreases of the inflammatory disorders in the hepatic parenchyma; celecoxib pre-treatment seemed to be more effective against renal inflammation. Indomethacin pre-treatment only slightly reduced the inflammatory disorders in the tissues. These results suggest that the induced inflammation response in liver was mediated mainly by PLA2 activation, while the renal inflammatory process was mediated by prostaglandin formation by COX-2. These findings provide additional insight toward the understanding of activated pathways and related mechanisms involved in scorpion envenoming syndrome.

  17. Choose your weapon: defensive behavior is associated with morphology and performance in scorpions.

    Science.gov (United States)

    van der Meijden, Arie; Lobo Coelho, Pedro; Sousa, Pedro; Herrel, Anthony

    2013-01-01

    Morphology can be adaptive through its effect on performance of an organism. The effect of performance may, however, be modulated by behavior; an organism may choose a behavioral option that does not fully utilize its maximum performance. Behavior may therefore be decoupled from morphology and performance. To gain insight into the relationships between these levels of organization, we combined morphological data on defensive structures with measures of defensive performance, and their utilization in defensive behavior. Scorpion species show significant variation in the morphology and performance of their main defensive structures; their chelae (pincers) and the metasoma ("tail") carrying the stinger. Our data show that size-corrected pinch force varies to almost two orders of magnitude among species, and is correlated with chela morphology. Chela and metasoma morphology are also correlated to the LD50 of the venom, corroborating the anecdotal rule that dangerously venomous scorpions can be recognized by their chelae and metasoma. Analyses of phylogenetic independent contrasts show that correlations between several aspects of chela and metasoma morphology, performance and behavior are present. These correlations suggest co-evolution of behavior with morphology and performance. Path analysis found a performance variable (pinch force) to partially mediate the relationship between morphology (chela aspect ratio) and behavior (defensive stinger usage). We also found a correlation between two aspects of morphology: pincer finger length correlates with the relative "thickness" (aspect ratio) of the metasoma. This suggests scorpions show a trade-off between their two main weapon complexes: the metasoma carrying the stinger, and the pedipalps carrying the chelae.

  18. Convulsive and Neurodegenerative Effects in Rats of Some Isolated Toxins from the Tityus bahiensis Scorpion Venom

    OpenAIRE

    2013-01-01

    Despite Tityus bahiensis being one of the most dangerous scorpions in Brazil, there are few studies about the effects of its venom, which acts mainly on the central nervous system. Previous studies demonstrated the convulsive ability of this venom. The present work aimed to study the hippocampal effects in rats of some toxins isolated from pool V, which induces a pronounced epileptogenic effect. The pool was separated by reverse-phase HPLC, and the peaks with higher yield (Tb V-1, V-5, V-24, ...

  19. Exploiting Cross-reactivity to Neutralize Two Different Scorpion Venoms with One Single Chain Antibody Fragment*

    OpenAIRE

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D.; Becerril, Baltazar

    2010-01-01

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Bece...

  20. The new kappa-KTx 2.5 from the scorpion Opisthacanthus cayaporum.

    Science.gov (United States)

    Camargos, Thalita Soares; Restano-Cassulini, Rita; Possani, Lourival Domingos; Peigneur, Steve; Tytgat, Jan; Schwartz, Carlos Alberto; Alves, Erica Maria C; de Freitas, Sonia Maria; Schwartz, Elisabeth Ferroni

    2011-07-01

    The kappa-KTx family of peptides, which is the newest K⁺-channel blocker family from scorpion venom, is present in scorpions from the families Scorpionidae and Liochelidae. Differently from the other scorpion KTx families, the three-dimensional structure of the known kappa-KTxs toxins is formed by two parallel α-helices linked by two disulfide bridges. Here, the characterization of a new kappa-KTx peptide, designated kappa-KTx 2.5, derived from the Liochelidae scorpion Opisthacanthus cayaporum, is described. This peptide was purified by HPLC and found to be identical to OcyC8, a predicted mature sequence precursor (UniProtKB C5J89) previously described by our group. The peptide was chemically synthesized and the circular dichroism (CD) spectra of both, native and synthetic, conducted at different temperatures in water and water/trifluoroethanol (TFE), showed a predominance of α-helices. The kappa-KTx 2.5 is heat stable and was shown to be a blocker of K⁺-currents on hKv1.1, and hKv1.4, with higher affinity for Kv1.4 channels (IC₅₀= 71 μM). Similarly to the other kappa-KTxs, the blockade of K⁺-channels occurred at micromolar concentrations, leading to uncertainness about their proper molecular target, and consequently their pharmacologic effect. In order to test other targets, kappa-KTx2.5 was tested on other K⁺-channels, on Na⁺-channels, on bacterial growth and on smooth muscle tissue, a known assay to identify possible bradykinin-potentiating peptides, due to the presence of two contiguous prolines at the C-terminal sequence. It has no effect on the targets used except on hKv1.1, and hKv1.4 expressed in Chinese hamster ovary cells. Since the only plausible function found for kappa-KTx2.5 seems to be the blockade of K⁺-channels, a discussion regarding the analysis of structure-function relationships is included in this communication, based on sequence alignments of members of the kappa-KTx toxin family, and on computational simulation of a

  1. Bothriurus pichicuy, nuevo escorpión chileno del grupo vittatus (Scorpiones, Bothriuridae

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    Mattoni Camilo I.

    2002-01-01

    Full Text Available Bothriurus pichicuy, a new scorpion species from the center coast of Chile, is described. It belongs to the vittatus species-group, and differs from the others species in the group by the pigmentation patterns of the prosoma, mesosoma and venter of metasoma, by the development and arrangement of the ventral keels of caudal segment V, and for its small size. The species is the only representative of the vittatus species-group that lives in sympatry with another Bothriurus species: B. coriaceus Pocock, 1893, from the coastal desert of Chile. Records of B. pichicuy came from the provinces of Petorca and Choapa.

  2. The first species of Thelastoma Leidy, 1849 (Nematoda: Thelastomatidae) parasitising the scorpion Euscorpius italicus (Chactidae: Scorpionidea).

    Science.gov (United States)

    Barus, Vlastimil; Koubková, Bozena

    2002-10-01

    A new species, Thelastoma euscorpii, (Thelastomatidae: Oxyuroidea) is described from Euscorpius italicus (Chactidae) on Pag Island (Kvarner Islands), Croatia. The new taxon differs from all other species of Thelastoma in having a cuticle with fine transverse striae. The excretory pore of the female specimens is located in a prebulbar position, the tail is short and subfiliform (5.5-9.3% of the total body length), and the eggs are small (47-52 x 24-29 microm). The males have a short oesophagus and no spicules. This is the first nematode species found in scorpions (Scorpionidea).

  3. Characterization of Kbot21 Reveals Novel Side Chain Interactions of Scorpion Toxins Inhibiting Voltage-Gated Potassium Channels.

    Science.gov (United States)

    ElFessi-Magouri, Rym; Peigneur, Steve; Othman, Houcemeddine; Srairi-Abid, Najet; ElAyeb, Mohamed; Tytgat, Jan; Kharrat, Riadh

    2015-01-01

    Scorpion toxins are important pharmacological tools for probing the physiological roles of ion channels which are involved in many physiological processes and as such have significant therapeutic potential. The discovery of new scorpion toxins with different specificities and affinities is needed to further characterize the physiology of ion channels. In this regard, a new short polypeptide called Kbot21 has been purified to homogeneity from the venom of Buthus occitanus tunetanus scorpion. Kbot21 is structurally related to BmBKTx1 from the venom of the Asian scorpion Buthus martensii Karsch. These two toxins differ by only two residues at position 13 (R /V) and 24 (D/N).Despite their very similar sequences, Kbot21 and BmBKTx1 differ in their electrophysiological activities. Kbot21 targets KV channel subtypes whereas BmBKTx1 is active on both big conductance (BK) and small conductance (SK) Ca2+-activated K+ channel subtypes, but has no effects on Kv channel subtypes. The docking model of Kbot21 with the Kv1.2 channel shows that the D24 and R13 side-chain of Kbot21 are critical for its interaction with KV channels.

  4. Insights into the Hypertensive Effects of Tityus serrulatus Scorpion Venom: Purification of an Angiotensin-Converting Enzyme-Like Peptidase

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    Daniela Cajado-Carvalho

    2016-11-01

    Full Text Available The number of cases of envenomation by scorpions has grown significantly in Brazil since 2007, with the most severe cases being caused by the Tityus serrulatus scorpion. Although envenomed patients mostly suffer neurotoxic manifestations, other symptoms, such as hypertension, cannot be exclusively attributed to neurotoxins. Omics analyses have detected plentiful amounts of metalloproteases in T. serrulatus venom. However, the roles played by these enzymes in envenomation are still unclear. Endeavoring to investigate the functions of scorpion venom proteases, we describe here for the first time an Angiotensin I-Converting Enzyme-like peptidase (ACE-like purified from T. serrulatus venom. The crude venom cleaved natural and fluorescent substrates and these activities were inhibited by captopril. Regarding the serum neutralization, the scorpion antivenom was more effective at blocking the ACE-like activity than arachnid antivenom, although neither completely inhibited the venom cleavage action, even at higher doses. ACE-like was purified from the venom after three chromatographic steps and its identity was confirmed by mass spectrometric and transcriptomic analyses. Bioinformatics analysis showed homology between the ACE-like transcript sequences from Tityus spp. and human testis ACE. These findings advance our understanding of T. serrulatus venom components and may improve treatment of envenomation victims, as ACE-like may contribute to envenomation symptoms, especially the resulting hypertension.

  5. Insights into the Hypertensive Effects of Tityus serrulatus Scorpion Venom: Purification of an Angiotensin-Converting Enzyme-Like Peptidase

    Science.gov (United States)

    Cajado-Carvalho, Daniela; Kuniyoshi, Alexandre Kazuo; Duzzi, Bruno; Iwai, Leo Kei; de Oliveira, Úrsula Castro; Junqueira de Azevedo, Inácio de Loiola Meirelles; Kodama, Roberto Tadashi; Portaro, Fernanda Vieira

    2016-01-01

    The number of cases of envenomation by scorpions has grown significantly in Brazil since 2007, with the most severe cases being caused by the Tityus serrulatus scorpion. Although envenomed patients mostly suffer neurotoxic manifestations, other symptoms, such as hypertension, cannot be exclusively attributed to neurotoxins. Omics analyses have detected plentiful amounts of metalloproteases in T. serrulatus venom. However, the roles played by these enzymes in envenomation are still unclear. Endeavoring to investigate the functions of scorpion venom proteases, we describe here for the first time an Angiotensin I-Converting Enzyme-like peptidase (ACE-like) purified from T. serrulatus venom. The crude venom cleaved natural and fluorescent substrates and these activities were inhibited by captopril. Regarding the serum neutralization, the scorpion antivenom was more effective at blocking the ACE-like activity than arachnid antivenom, although neither completely inhibited the venom cleavage action, even at higher doses. ACE-like was purified from the venom after three chromatographic steps and its identity was confirmed by mass spectrometric and transcriptomic analyses. Bioinformatics analysis showed homology between the ACE-like transcript sequences from Tityus spp. and human testis ACE. These findings advance our understanding of T. serrulatus venom components and may improve treatment of envenomation victims, as ACE-like may contribute to envenomation symptoms, especially the resulting hypertension. PMID:27886129

  6. Comments on Environmental and Sanitary Aspects of the Scorpionism by Tityus trivittatus in Buenos Aires City, Argentina

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    Adolfo Rafael de Roodt

    2014-04-01

    Full Text Available Deaths by venomous animals are medical emergencies that can lead to death and thus constitute sanitary problems in some regions of the world. In the South of America, the accidents by these animals are a common sanitary problem especially in warm, tropical or subtropical regions, related with rural work in several countries. Argentina is located in the extreme South of South America and a minor part of the continental surface is in tropical or subtropical regions, where most of the accidents by venomous animals happen. However, in the big cities in the center and South of the country, with no relation to rural work, scorpionism, mostly due to the synanthropic and facultative parthenogenetic scorpion Tityus trivittatus, has become a sanitary problem in the last few decades. This scorpion is present in the biggest cities of Argentina and in the last decades has killed over 20 children in provinces of the center and north of the country, mostly in big cities. In addition, it seems that this species is growing and spreading in new regions of the cities. In this revision, some characteristics of this scorpion regarding its habitat, spreading in Buenos Aires city, combat measures and available treatments are discussed.

  7. Characterization of Kbot21 Reveals Novel Side Chain Interactions of Scorpion Toxins Inhibiting Voltage-Gated Potassium Channels.

    Directory of Open Access Journals (Sweden)

    Rym ElFessi-Magouri

    Full Text Available Scorpion toxins are important pharmacological tools for probing the physiological roles of ion channels which are involved in many physiological processes and as such have significant therapeutic potential. The discovery of new scorpion toxins with different specificities and affinities is needed to further characterize the physiology of ion channels. In this regard, a new short polypeptide called Kbot21 has been purified to homogeneity from the venom of Buthus occitanus tunetanus scorpion. Kbot21 is structurally related to BmBKTx1 from the venom of the Asian scorpion Buthus martensii Karsch. These two toxins differ by only two residues at position 13 (R /V and 24 (D/N.Despite their very similar sequences, Kbot21 and BmBKTx1 differ in their electrophysiological activities. Kbot21 targets KV channel subtypes whereas BmBKTx1 is active on both big conductance (BK and small conductance (SK Ca2+-activated K+ channel subtypes, but has no effects on Kv channel subtypes. The docking model of Kbot21 with the Kv1.2 channel shows that the D24 and R13 side-chain of Kbot21 are critical for its interaction with KV channels.

  8. Genomic cloning, characterization and statistical analysis of an antitumor-analgesic peptide from Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Cui, Yong; Liu, Yanfeng; Chen, Qiqing; Zhang, Rong; Song, Yongbo; Jiang, Zhuopu; Wu, Chunfu; Zhang, Jinghai

    2010-09-01

    The genomic DNA sequence encoding an antitumor-analgesic peptide was amplified from the genome of Chinese scorpion Buthus martensii Karsch (BmKAGAP), then cloned and sequenced. An intron, with a high A + T content (61.6%), splits a glycine codon near the end of the precursor signal peptide and the consensus GT/AG splice junction was identified in the BmKAGAP gene. Using PCR amplification, we confirmed the identity of our cloned cDNA, and found that the BmKAGAP gene contained an intron of 506 bp in length, which was almost identical to that of the characterized scorpion sodium channel ligands in size, consensus junctions, putative branch point and A + T content. This is the first report of using a statistical method for Chinese scorpion B. martensii Karsch genomic sequence analysis, involving the extraction of some putative transcription regulatory factors. Moreover, it establishes a theoretical foundation for studying the relationship between scorpion evolution, gene expression and protein function.

  9. Comparison of the Amino-Acid Content in Pharmacopuncture Extracts Taken from a Scorpion's Body and from Its Tail

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    Lee Jin-Ho

    2013-06-01

    Full Text Available Objective: This study was conducted to investigate the amino-acid compositions of pharmacopuncture extracts taken from the body and from the tail of Buthus martensii Karsch, which are frequently prescribed in Oriental medicine. Methods: Amino acids in hot water and 70% ethanol extracts taken from the scorpion’s whole body and from its tail were screened by using high performance liquid chromatography (HPLC. The experiments were performed with linearity, precision and accuracy. Results: The results of the amino-acid-composition analysis showed that the Buthus martensii Karsch extracts contained various amino acids such as aspartic acid, histidine, alanine, tyrosine, and cystine. The amino-acid analysis showed that the hot water extract was more beneficial than the ethanol extract, except for histidine. The amino acids from the tail and the body of the scorpion were compared, and the concentration of aspartic acid in the extract from the scorpion’s tail was two times that found in the extract from its body. The results of validation experiments were all satisfactory. Conclusion: Studies on the ingredients in extracts from a scorpion other than buthotoxin may demonstrate that the antiepileptic efficacy, anticancer activity, antithrombotic action and analgesic effect are enhanced. Using only the tail of the scorpion when pharmacopuncture is dispensed may be beneficial because the extracts from the tail of the scorpion have higher potency than those from the whole body.

  10. A FOSSIL WHIP-SCORPION (ARACHNIDA: THELYPHONIDA FROM THE UPPER CARBONIFEROUS OF THE CARNIC ALPS (FRIULI, NE ITALY

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    PAUL A. SELDEN

    2016-03-01

    Full Text Available A new and well-preserved fossil whip scorpion (Arachnida: Uropygi: Thelyphonida is described from the Late Carboniferous of the Carnic Alps, Friuli, Italy. It is referred to Parageralinura marsiglioi n. sp. The new specimen is the first Carboniferous arachnid to be described from mainland Italy and is possibly the youngest Palaeozoic thelyphonid.

  11. X-ray Structure of Native Scorpion Toxin BmBKTx1 by Racemic Protein Crystallography Using Direct Methods

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Kalyaneswar; Pentelute, Brad L.; Tereshko, Valentina; Kossiakoff, Anthony A.; Kent, Stephen B.H.; (UC)

    2009-04-08

    Racemic protein crystallography, enabled by total chemical synthesis, has allowed us to determine the X-ray structure of native scorpion toxin BmBKTx1; direct methods were used for phase determination. This is the first example of a protein racemate that crystallized in space group I41/a.

  12. Cooperative Exploration of Rough Martian Terrains with the "Scorpion" Legged Robot as an Adjunct to a Rover.

    Science.gov (United States)

    Colombano, Silvano P.; Kirchner, Frank; Spenneberg, Dirk; Starman, Jared; Hanratty, James; Kovsmeyer, David (Technical Monitor)

    2003-01-01

    NASA needs autonomous robotic exploration of difficult (rough and/or steep) scientifically interesting Martian terrains. Concepts involving distributed autonomy for cooperative robotic exploration are key to enabling new scientific objectives in robotic missions. We propose to utilize a legged robot as an adjunct scout to a rover for access to difficult - scientifically interesting - terrains (rocky areas, slopes, cliffs). Our final mission scenario involves the Ames rover platform "K9" and Scorpion acting together to explore a steep cliff, with the Scorpion robot rappelling down using the K9 as an anchor as well as mission planner and executive. Cooperation concepts, including wheeled rappelling robots have been proposed before. Now we propose to test the combined advantages of a wheeled vehicle with a legged scout as well as the advantages of merging of high level planning and execution with biologically inspired, behavior based robotics. We propose to use the 8-legged, multifunctional autonomous robot platform Scorpion that is currently capable of: Walking on different terrains (rocks, sand, grass, ...). Perceiving its environment and modifying its behavioral pattern accordingly. These capabilities would be extended to enable the Scorpion to: communicate and cooperate with a partner robot; climb over rocks, rubble piles, and objects with structural features. This will be done in the context of exploration of rough terrains in the neighborhood of the rover, but inaccessible to it, culminating in the added capability of rappelling down a steep cliff for both vertical and horizontal terrain observation.

  13. Morbidity, surveillance and epidemiology of scorpion sting, cutaneous leishmaniasis and pediculosis capitis in Bandar-mahshahr County, Southwestern Iran

    Institute of Scientific and Technical Information of China (English)

    Hamid Kassiri; Mohammad-Hossein Feizhaddad; Mohammad Abdehpanah

    2014-01-01

    Objective:To study epidemiologic features of scorpion stings, patients with cutaneous leishmaniasis and pediculosis capitis cases inBandar-mahshahrCounty,SouthwesternIran, during2008-2009.Methods:A descriptive study was conducted on the referred individuals with stung scorpions, pediculosis capitis and cutaneous leishmaniasis attending health centers fromBandar-mahshahrCounty in2008.The patients' medical records with epidemiologic and demographic data were collected.UsingSPSS, we have attempted to summarize statistics, namely frequencies and percentages.Results:A total of135 scorpion stings patients were studied.Of these,34.8% were female and65.2% male.Most of theScorpion stings were recorded in the21-30 year age group(37.8%).A total of82 cases of cutaneous leishmaniasis were studied in this assignment that all cases have been reported from urban health centers.Considering number of wounds on the body the maximum of the patients(37.6%) had only one lesion.In this study, 12 referred patients from the health centers were studied for pediculosis capitis.According to obtained information one of the patients was male and11 patients were female.Conclusions:Some important measures, such aseducation, health promotion and public participation should be implemented for preventing of these diseases.

  14. Microwhip scorpions (Palpigradi feed on heterotrophic cyanobacteria in Slovak caves--a curiosity among Arachnida.

    Directory of Open Access Journals (Sweden)

    Jaroslav Smrž

    Full Text Available To date, only morphological and anatomical descriptions of microwhip scorpions (Arachnida: Palpigradi have been published. This very rare group is enigmatic not only in its relationships to other arachnids, but especially due to the fact that these animals dwell only underground (in caves, soil, and interstitial spaces. We observed the curious feeding habit of the microwhip scorpion Eukoenenia spelaea over the course of one year in Ardovská Cave, located in Slovakia's Karst region. We chose histology as our methodology in studying 17 specimens and based it upon Masson's triple staining, fluorescent light and confocal microscopy. Single-celled cyanobacteria (blue-green algae were conspicuously predominant in the gut of all studied palpigrades. Digestibility of the consumed cyanobacteria was supported by the presence of guanine crystals, glycogen deposits and haemocytes inside the palpigrade body. Cyanobacteria, the oldest cellular organisms on Earth, are very resistant to severe conditions in caves, including even darkness. Therefore, the cyanobacteria are able to survive in dark caves as nearly heterotrophic organisms and are consumed by cave palpigrades. Such feeding habit is extraordinary within the almost wholly predacious orders of the class Arachnida, and particularly so due to the type of food observed.

  15. Microwhip scorpions (Palpigradi) feed on heterotrophic cyanobacteria in Slovak caves--a curiosity among Arachnida.

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    Smrž, Jaroslav; Kováč, Ĺubomír; Mikeš, Jaromír; Lukešová, Alena

    2013-01-01

    To date, only morphological and anatomical descriptions of microwhip scorpions (Arachnida: Palpigradi) have been published. This very rare group is enigmatic not only in its relationships to other arachnids, but especially due to the fact that these animals dwell only underground (in caves, soil, and interstitial spaces). We observed the curious feeding habit of the microwhip scorpion Eukoenenia spelaea over the course of one year in Ardovská Cave, located in Slovakia's Karst region. We chose histology as our methodology in studying 17 specimens and based it upon Masson's triple staining, fluorescent light and confocal microscopy. Single-celled cyanobacteria (blue-green algae) were conspicuously predominant in the gut of all studied palpigrades. Digestibility of the consumed cyanobacteria was supported by the presence of guanine crystals, glycogen deposits and haemocytes inside the palpigrade body. Cyanobacteria, the oldest cellular organisms on Earth, are very resistant to severe conditions in caves, including even darkness. Therefore, the cyanobacteria are able to survive in dark caves as nearly heterotrophic organisms and are consumed by cave palpigrades. Such feeding habit is extraordinary within the almost wholly predacious orders of the class Arachnida, and particularly so due to the type of food observed.

  16. Induction of neutralizing antibodies in mice immunized with scorpion toxins detoxified by liposomal entrapment

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    S.G. Fonseca

    1997-07-01

    Full Text Available The possibility of producing neutralizing antibodies against the lethal effects of scorpion toxins was evaluated in the mouse model by immunization with an immunogen devoid of toxicity. A toxic fraction (5 mg from the venom of the scorpion Tityus serrulatus was entrapped in sphingomyelin-cholesterol liposomes. The liposomes were treated for 1 h at 37oC with a 1% (w/w trypsin solution in 0.2 M sodium carbonate buffer, pH 8.3. This treatment led to a strong reduction in venom toxicity. Immunization was performed as follows: mice were injected sc with 20 µg of the liposome-entrapped toxic fraction on days 1 and 21 and a final injection (20 µg was administered ip on day 36. After injection of the immunogen, all mice developed an IgG response which was shown to be specific for the toxic antigen. The antibodies were measured 10 days after the end of the immunization protocol. In an in vitro neutralization assay we observed that pre-incubation of a lethal dose of the toxic fraction with immune serum strongly reduced its toxicity. In vivo protection assays showed that mice with anti-toxin antibodies could resist the challenge with the toxic fraction, which killed, 30 min after injection, all non-immune control mice

  17. Profiling the resting venom gland of the scorpion Tityus stigmurus through a transcriptomic survey

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    Almeida Diego D

    2012-08-01

    Full Text Available Abstract Background The scorpion Tityus stigmurus is widely distributed in Northeastern Brazil and known to cause severe human envenoming, inducing pain, hyposthesia, edema, erythema, paresthesia, headaches and vomiting. The present study uses a transcriptomic approach to characterize the gene expression profile from the non-stimulated venom gland of Tityus stigmurus scorpion. Results A cDNA library was constructed and 540 clones were sequenced and grouped into 153 clusters, with one or more ESTs (expressed sequence tags. Forty-one percent of ESTs belong to recognized toxin-coding sequences, with transcripts encoding antimicrobial toxins (AMP-like being the most abundant, followed by alfa KTx- like, beta KTx-like, beta NaTx-like and alfa NaTx-like. Our analysis indicated that 34% of the transcripts encode “other possible venom molecules”, which correspond to anionic peptides, hypothetical secreted peptides, metalloproteinases, cystein-rich peptides and lectins. Fifteen percent of ESTs are similar to cellular transcripts. Sequences without good matches corresponded to 11%. Conclusions This investigation provides the first global view of gene expression of the venom gland from Tityus stigmurus under resting conditions. This approach enables characterization of a large number of venom gland component molecules, which belong either to known or non yet described types of venom peptides and proteins from the Buthidae family.

  18. BmK-YA, an enkephalin-like peptide in scorpion venom.

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    Yan Zhang

    Full Text Available By screening extracts of venom from the Asian scorpion Buthus martensii Karsch (BmK for their abilities to activate opioid receptors, we have identified BmK-YA, an amidated peptide containing an enkephalin-like sequence. BmK-YA is encoded by a precursor that displays a signal sequence and contains four copies of BmK-YA sequences and four of His(4-BmK-YA, all flanked by single amino acid residues. BmK-YA and His(4-BmK-YA are amidated and thus fulfill the characteristics expected of bioactive peptides. BmK-YA can activate mammalian opioid receptors with selectivity for the δ subtype while His(4-BmK-YA is inactive at opioid receptors. The discovery of BmK-YA suggests that scorpion venom may represent a novel source of bioactive molecules targeting G protein-coupled receptors (GPCRs and reveal additional insights on the evolution of the opioid precursors.

  19. A 454 sequencing approach for large scale phylogenomic analysis of the common emperor scorpion (Pandinus imperator).

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    Roeding, Falko; Borner, Janus; Kube, Michael; Klages, Sven; Reinhardt, Richard; Burmester, Thorsten

    2009-12-01

    In recent years, phylogenetic tree reconstructions that rely on multiple gene alignments that had been deduced from expressed sequence tags (ESTs) have become a popular method in molecular systematics. Here, we present a 454 pyrosequencing approach to infer the transcriptome of the Emperor scorpion Pandinus imperator. We obtained 428,844 high-quality reads (mean length=223+/-50 b) from total cDNA, which were assembled into 8334 contigs (mean length 422+/-313 bp) and 26,147 singletons. About 1200 contigs were successfully annotated by BLAST and orthology search. Specific analyses of eight distinct hemocyanin sequences provided further proof for the quality of the 454 reads and the assembly process. The P. imperator sequences were included in a concatenated alignment of 149 orthologous genes of 67 metazoan taxa that covers 39,842 amino acids. After removal of low-quality regions, 11,168 positions were employed for phylogenetic reconstructions. Using Bayesian and maximum likelihood methods, we obtained strongly supported monophyletic Ecdysozoa, Arthropoda (excluding Tardigrada), Euarthropoda, Pancrustacea and Hexapoda. We also recovered the Myriochelata (Chelicerata+Myriapoda). Within the chelicerates, Pycnogonida form the sister group of Euchelicerata. However, Arachnida were found paraphyletic because the Acari (mites and ticks) were recovered as sister group of a clade comprising Xiphosura, Scorpiones and Araneae. In summary, we have shown that 454 pyrosequencing is a cost-effective method that provides sufficient data and coverage depth for gene detection and multigene-based phylogenetic analyses.

  20. Expression of functional recombinant scorpion beta-neurotoxin Css II in E. coli.

    Science.gov (United States)

    Johnson, T M; Quick, M W; Sakai, T T; Krishna, N R

    2000-06-01

    The gene for a beta-neurotoxin [Centruroides suffusus suffusus toxin II (Css II)] from the scorpion C. suffusus suffusus was synthesized by recursive PCR and cloned into the expression vector, pET15b. This recombinant vector was transformed into a thioredoxin mutant host bacterial cell, AD 494(DE3)pLysS, and expression was induced with isopropyl thiogalactoside (IPTG). Although the level of expression was low, the recombinant toxin was found only in the soluble fraction with no evidence for the formation of inclusion bodies as had been observed previously with other scorpion toxins. The recombinant Css II was purified by successive ion-exchange and hydrophobic interaction chromatography. Nuclear magnetic resonance (NMR) and circular dichroism (CD) spectral measurements indicate that the protein has a native structure with no indication of denatured species. The recombinant neurotoxin inhibits the uptake of [(3)H]GABA [gamma-aminobutyric acid (GABA)] in neuronal cells as effectively as natural beta-toxins.

  1. Scorpion Toxins Specific for Potassium (K+ Channels: A Historical Overview of Peptide Bioengineering

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    Zachary L. Bergeron

    2012-11-01

    Full Text Available Scorpion toxins have been central to the investigation and understanding of the physiological role of potassium (K+ channels and their expansive function in membrane biophysics. As highly specific probes, toxins have revealed a great deal about channel structure and the correlation between mutations, altered regulation and a number of human pathologies. Radio- and fluorescently-labeled toxin isoforms have contributed to localization studies of channel subtypes in expressing cells, and have been further used in competitive displacement assays for the identification of additional novel ligands for use in research and medicine. Chimeric toxins have been designed from multiple peptide scaffolds to probe channel isoform specificity, while advanced epitope chimerization has aided in the development of novel molecular therapeutics. Peptide backbone cyclization has been utilized to enhance therapeutic efficiency by augmenting serum stability and toxin half-life in vivo as a number of K+-channel isoforms have been identified with essential roles in disease states ranging from HIV, T-cell mediated autoimmune disease and hypertension to various cardiac arrhythmias and Malaria. Bioengineered scorpion toxins have been monumental to the evolution of channel science, and are now serving as templates for the development of invaluable experimental molecular therapeutics.

  2. Neutralizing Effects of Mimosa tenuiflora Extracts against Inflammation Caused by Tityus serrulatus Scorpion Venom

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    Mariana Angélica Oliveira Bitencourt

    2014-01-01

    Full Text Available Scorpion bite represents a significant and serious public health problem in certain regions of Brazil, as well as in other parts of the world. Inflammatory mediators are thought to be involved in the systemic and local immune response induced by Tityus serrulatus scorpion envenomation. The aim of this study was to evaluate the effect of extracts of Mimosa tenuiflora on model envenomation. In mice, the envenomation model is induced by Tityus serrulatus venom. Previous treatment of mice with fractions from M. tenuiflora was able to suppress the cell migration to the peritoneal cavity. The treatment of mice with M. tenuiflora extracts also decreased the levels of IL-6, IL-12, and IL-1β. We concluded that the administration of the extract and fractions resulted in a reduction in cell migration and showed a reduction in the level of proinflammatory cytokines. This study demonstrates, for the first time, the anti-inflammatory effect of aqueous extract from the Mimosa tenuiflora plant on T. serrulatus venom.

  3. Electrocardiographic changes in dog after injection of different doses of the venom of the scorpion Odonthobuthus

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    Sardar Jafari Shoorijeh

    2005-02-01

    Full Text Available There is scant information about biological effects of the venoms of scorpions on different organs. Sixteen healthy native dogs aged about 2 years with average body weight of 18.5 kg of both sexes were selected for this study. Dogs were divided randomly into four equal groups (4 dogs in each group. Clinical signs are recorded and electrocardiogram was obtained for each dog prior to injection of venom. In the control group 1 ml of saline solution was injected and the amount of equal to 0.1, 0.05 and 0.01 mg of venom powder per kg bwt were dissolved in 1 ml saline solution and injected intradermal in the abdominal region or hind limb of each dog in the second, third, and four groups, respectively. Clinical signs and electorcardiogram of each dog were recorded at different time intervals (5, 15, 30, 60, 90, 120, 180, 360 and 24 hours after injection of venom. The results of ECGs, in group 1 and 2 indicated advanced sinus arrhythmia, sinus arrest, sinoatrial standstill, sever bradycardia and tachycardia, first and second degree heart block, premature ventricular contraction, sinus bradycardia and ventricular fibrillation. In group 3, partial sinus arrhythmia, sinus tachycardia, sinus arrest, advanced sinus arrhythmia and tachycardia were observed. In conclusion, the venom of the scorpion Odonthobuthus produces very changes in electrocardiogram by its effects on autonomic system and adrenal gland.

  4. Thaler Konrad (wissenschaftliche Redaktion (2004: Diversität und Biologie von Webspinnen, Skorpionen und anderen Spinnentieren. Diversity and biology of spiders, scorpions and other arachnids

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    Blick, Theo

    2004-11-01

    Full Text Available book review: Thaler Konrad (wissenschaftliche Redaktion (2004: Diversität und Biologie von Webspinnen, Skorpionen und anderen Spinnentieren. Diversity and biology of spiders, scorpions and other arachnids.

  5. Epidemiological and spatial analysis of scorpion stings in two regions of Morocco: Marrakesh-Tensift-Al Haouz and Souss-Massa-Draa

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    Moulay Abdelmonaim El Hidan

    2016-04-01

    Full Text Available Objective: To describe and compare the epidemiological features of scorpionism during six years (2005–2010 in two regions of Morocco: Marrakesh-Tensift-Al Haouz and Souss-MassaDraa. Methods: Clinical and epidemiological data were obtained from medical records of the Moroccan Poison Control Center during 2005–2010. The data comprised demographics, sting characteristics and clinical severity classes. Digital maps were produced for envenomation and death incidence with the distribution of all scorpion species present on the studied area. Results: A total of 75313 scorpion sting cases were notified. The incidence of scorpion stings was 244 cases/100000 population/year and was significantly higher at Marrakesh-Tensift-Al Haouz than Souss-Massa-Draa. The general lethality rate was on an average of 0.28% with a higher rate in Marrakesh-Tensift-Al Haouz compared to Souss-Massa-Draa. There was a different distribution of cases between genders in the two studied regions. With respect to age groups, adults (more than 15 years were affected most compared to children. When analyzed according to the incidence in each province, the highest envenomation incidence was observed in Chichaoua. Concerning lethality, the highest lethality incidence was observed in the Kelaa. Based on this study, we could distinguish three zones: low scorpion stings occurrence without death, high incidence with low lethality and high scorpion stings rate with high lethality. Conclusions: Our data clearly demonstrate the correlation between scorpion stings incidence and the percentage of rural population in the different provinces. Additionally, the lethality incidence could be linked to the scorpion species of the studied area.

  6. A HindIII BAC library construction of Mesobuthus martensii Karsch (Scorpiones:Buthidae): an important genetic resource for comparative genomics and phylogenetic analysis.

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    Li, Songryong; Ma, Yibao; Jang, Shenghun; Wu, Yingliang; Liu, Hui; Cao, Zhijian; Li, Wenxin

    2009-12-01

    Scorpions are "living but sophisticated fossils" that have changed little in their morphology since their first appearance over the past 450 million years ago. To provide a genetic resource for understanding the evolution of scorpion genome and the relationships between scorpions and other organisms, we first determined the genome size of the scorpion Mesobuthus martensii Karsch (about 600 Mbp) in the order Scorpiones and constructed a HindIII BAC library of the male scorpion M. martensii Karsch from China. The BAC library consists of a total of 46,080 clones with an average insert size of 100 kb, providing a 7.7-fold coverage of the scorpion haploid genome size of 600 Mbp as revealed in this study. High-density colony hybridization-based library screening was performed using 18S-5.8S-28S rRNA gene that is one of the most commonly used phylogenetic markers. Both library screening and PCR identification results revealed six positive BAC clones which were overlapped, and formed a contig of approximately 120 kb covering the rDNA. BAC DNA sequencing analysis determined the complete sequence of M. martensii Karsch rDNA unit that has a total length of 8779 bp, including 1813 bp 18s rDNA, 157 bp 5.8s rDNA, 3823 bp 28s rDNA, 530 bp ETS, 2168 bp ITS1 and 288 bp ITS2. Interestingly, some tandem repeats are present in the rRNA intergenic sequence (IGS) and ITS1/2 regions. These results demonstrated that the BAC library of the scorpion M. martensii Karsch and the complete sequence of rDNA unit will provide important genetic resources and tools for comparative genomics and phylogenetic analysis.

  7. Epidemiological and spatial analysis of scorpion stings in two regions of Morocco:Marrakesh-Tensift-Al Haouz and Souss-Massa-Draa

    Institute of Scientific and Technical Information of China (English)

    Moulay Abdelmonaim El Hidan; Oulaid Touloun; Rhizlane El Oufir; Ali Boumezzough

    2016-01-01

    Objective:To describe and compare the epidemiological features of scorpionism during six years (2005–2010) in two regions of Morocco: Marrakesh-Tensift-Al Haouz and Souss-Massa-Draa. Methods: Clinical and epidemiological data were obtained from medical records of the Moroccan Poison Control Center during 2005–2010. The data comprised demographics, sting characteristics and clinical severity classes. Digital maps were produced for envenomation and death incidence with the distribution of all scorpion species present on the studied area. Results:A total of 75 313 scorpion sting cases were notified. The incidence of scorpion stings was 244 cases/100 000 population/year and was significantly higher at Marrakesh-Tensift-Al Haouz than Souss-Massa-Draa. The general lethality rate was on an average of 0.28% with a higher rate in Marrakesh-Tensift-Al Haouz compared to Souss-Massa-Draa. There was a different distribution of cases between genders in the two studied regions. With respect to age groups, adults (more than 15 years) were affected most compared to children. When analyzed according to the incidence in each province, the highest envenomation incidence was observed in Chichaoua. Concerning lethality, the highest lethality incidence was observed in the Kelaa. Based on this study, we could distinguish three zones: low scorpion stings occurrence without death, high incidence with low lethality and high scorpion stings rate with high lethality. Conclusions: Our data clearly demonstrate the correlation between scorpion stings incidence and the percentage of rural population in the different provinces. Additionally, the lethality incidence could be linked to the scorpion species of the studied area.

  8. Effect of scorpion toxin on the enterochromaffin-like cells in normal and Trypanosoma cruzi-infected rats: a morphological study

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    N. H. Toppa

    1989-02-01

    Full Text Available Intravenous injection of scorpion toxin (Tityus serrulatus in normal and Trypanosoma cruzi infected rats did not cause ultrastructural morphologic changes on enterochromaffin-like (ECL cells of the stomach, although it induced a significant increase of the gastric secretion. Our data seem to indicate that gastric ECL cells structure is not affected by stimulation with scorpion toxin or by acute infection with T. cruzi in the rat.

  9. Isolation and characterization of CvIV4: a pain inducing α-scorpion toxin.

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    Ashlee H Rowe

    Full Text Available BACKGROUND: Among scorpion species, the Buthidae produce the most deadly and painful venoms. However, little is known regarding the venom components that cause pain and their mechanism of action. Using a paw-licking assay (Mus musculus, this study compared the pain-inducing capabilities of venoms from two species of New World scorpion (Centruroides vittatus, C. exilicauda belonging to the neurotoxin-producing family Buthidae with one species of non-neurotoxin producing scorpion (Vaejovis spinigerus in the family Vaejovidae. A pain-inducing α-toxin (CvIV4 was isolated from the venom of C. vittatus and tested on five Na(+ channel isoforms. PRINCIPAL FINDINGS: C. vittatus and C. exilicauda venoms produced significantly more paw licking in Mus than V. spinigerus venom. CvIV4 produced paw licking in Mus equivalent to the effects of whole venom. CvIV4 slowed the fast inactivation of Na(v1.7, a Na(+ channel expressed in peripheral pain-pathway neurons (nociceptors, but did not affect the Na(v1.8-based sodium currents of these neurons. CvIV4 also slowed the fast inactivation of Na(v1.2, Na(v1.3 and Na(v1.4. The effects of CvIV4 are similar to Old World α-toxins that target Na(v1.7 (AahII, BmK MI, LqhIII, OD1, however the primary structure of CvIV4 is not similar to these toxins. Mutant Na(v1.7 channels (D1586A and E1589Q, DIV S3-S4 linker reduced but did not abolish the effects of CvIV4. CONCLUSIONS: This study: 1 agrees with anecdotal evidence suggesting that buthid venom is significantly more painful than non-neurotoxic venom; 2 demonstrates that New World buthids inflict painful stings via toxins that modulate Na(+ channels expressed in nociceptors; 3 reveals that Old and New World buthids employ similar mechanisms to produce pain. Old and New World α-toxins that target Na(v1.7 have diverged in sequence, but the activity of these toxins is similar. Pain-inducing toxins may have evolved in a common ancestor. Alternatively, these toxins may be the

  10. Functional characterization of two novel scorpion sodium channel toxins from Lychas mucronatus.

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    Xu, Lingna; Li, Tian; Liu, Honglian; Yang, Fan; Liang, Songping; Cao, Zhijian; Li, Wenxin; Wu, Yingliang

    2014-11-01

    The diverse α-scorpion toxins are invaluable pharmacological tools and potential drugs targeting sodium channels, but the pharmacological profiles of most toxins remains unknown so far. Here, we reported pharmacological activities of two novel α-scorpion toxins LmαTX3 and LmαTX5 from the Lychas mucronatus. Using the expression vector pET-28a, the recombinant LmαTX3 and LmαTX5 were separated by RP-HPLC and identified by MALDI-TOF-MS. Subsequently, sodium channels rNav1.2, mNav1.4, hNav1.5 and hNav1.7 were used for evaluating the pharmacological activities of LmαTX3 and LmαTX5 toxins. The electrophysiological experiments showed that both 10 μM recombinant LmαTX3 and LmαTX5 seriously inhibited the fast inactivation of mNav1.4 and hNav1.5 channels, moderately affected hNav1.7 channel, and hardly modulated rNav1.2 channel. The dose-response experiments further indicated the EC50 values of LmαTX3 were 4.98 ± 0.79 μM for mNav1.4, 1.23 ± 0.31 μM for hNav1.5 and 31.46 ± 2.32 μM for hNav1.7 channels, respectively. Similar pharmacological profiles of recombinant LmαTX5 were also observed, and its EC50 values were 4.53 ± 1.38 μM, 1.03 ± 0.43 μM and 67.62 ± 2.31 μM for mNav1.4, hNav1.5 and hNav1.7, respectively. In addition, the recombinant LmαTX3 from the vector pET-14b had much less effect on the fast inactivation of mNav1.4, hNav1.5 and hNav1.7 channels, which indicated that the expression vector pET-14b likely played a critical role in toxin function. Together, these findings first highlighted that scorpion toxins from L. mucronatus were a new molecular resource of discovering pharmacological probes and prospective drugs targeting sodium channels in the future.

  11. Partial in vitro and in vivo red scorpion venom neutralization activity of Andrographis paniculata

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    Ranjana I Brahmane

    2011-01-01

    Full Text Available Objective: Red scorpion (Mesobuthus tamulus is the most lethal among all poisonous species of scorpions. Envenoming by Mesobuthus tamulus is quite common along the western coast of India, without any established therapy. Andrographis paniculata is one of the plants that has long been used in traditional herbal medicine for the treatment of poisoning by animal bites. Hence, the study was planned to evaluate the ethanolic extract of Andrographis paniculata for the treatment of Mesobuthus tamulus envenoming. Materials and Methods: Ethanolic extract of the plant Andrographis paniculata was obtained using a soxhelet apparatus. Lyophilized venom sample of Mesobuthus tamulus was used. Swiss albino mice weighing 20-30 g were used in the study. Calculation of LD 99 of Mesobuthus tamulus venom was performed using Turner′s method. Acute toxicity of Mesobuthus tamulus venom and its neutralization by the plant extract at a dose of 1 g/kg and 2 g/kg in vivo was seen. Neutralization of the lethal venom effect of Mesobuthus tamulus by plant extract at the dose of 1 g/kg and 2 g/kg by Alam and Gome′s method (in vitro was also seen. Results: The LD 99 of Mesobuthus tamulus venom from this study was determined to be 25.12 ΅g/g and the LD 50 was 15.85 ΅g/g. In the acute toxicity and in vivo neutralization study, plant extract at the dose of 1 g/kg and 2 g/kg resulted in a mean survival of 62.667 min and 39.333 min, respectively. Neutralization of the lethal venom effect of Mesobuthus tamulus by the plant extract at the dose of 1 g/kg and 2 g/kg by Alam and Gome′s method (in vitro showed a mean survival of 49.667 min and 42.5 min, respectively. Conclusion: The ethanolic extract of Adrographis paniculata has some protective effect against the red scorpion venom in mice but does not offer any survival benefit.

  12. Partial Agonist and Antagonist Activities of a Mutant Scorpion β-Toxin on Sodium Channels*

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    Karbat, Izhar; Ilan, Nitza; Zhang, Joel Z.; Cohen, Lior; Kahn, Roy; Benveniste, Morris; Scheuer, Todd; Catterall, William A.; Gordon, Dalia; Gurevitz, Michael

    2010-01-01

    Scorpion β-toxin 4 from Centruroides suffusus suffusus (Css4) enhances the activation of voltage-gated sodium channels through a voltage sensor trapping mechanism by binding the activated state of the voltage sensor in domain II and stabilizing it in its activated conformation. Here we describe the antagonist and partial agonist properties of a mutant derivative of this toxin. Substitution of seven different amino acid residues for Glu15 in Css4 yielded toxin derivatives with both increased and decreased affinities for binding to neurotoxin receptor site 4 on sodium channels. Css4E15R is unique among this set of mutants in that it retained nearly normal binding affinity but lost its functional activity for modification of sodium channel gating in our standard electrophysiological assay for voltage sensor trapping. More detailed analysis of the functional effects of Css4E15R revealed weak voltage sensor trapping activity, which was very rapidly reversed upon repolarization and therefore was not observed in our standard assay of toxin effects. This partial agonist activity of Css4E15R is observed clearly in voltage sensor trapping assays with brief (5 ms) repolarization between the conditioning prepulse and the test pulse. The effects of Css4E15R are fit well by a three-step model of toxin action involving concentration-dependent toxin binding to its receptor site followed by depolarization-dependent activation of the voltage sensor and subsequent voltage sensor trapping. Because it is a partial agonist with much reduced efficacy for voltage sensor trapping, Css4E15R can antagonize the effects of wild-type Css4 on sodium channel activation and can prevent paralysis by Css4 when injected into mice. Our results define the first partial agonist and antagonist activities for scorpion toxins and open new avenues of research toward better understanding of the structure-function relationships for toxin action on sodium channel voltage sensors and toward potential toxin

  13. Partial agonist and antagonist activities of a mutant scorpion beta-toxin on sodium channels.

    Science.gov (United States)

    Karbat, Izhar; Ilan, Nitza; Zhang, Joel Z; Cohen, Lior; Kahn, Roy; Benveniste, Morris; Scheuer, Todd; Catterall, William A; Gordon, Dalia; Gurevitz, Michael

    2010-10-01

    Scorpion β-toxin 4 from Centruroides suffusus suffusus (Css4) enhances the activation of voltage-gated sodium channels through a voltage sensor trapping mechanism by binding the activated state of the voltage sensor in domain II and stabilizing it in its activated conformation. Here we describe the antagonist and partial agonist properties of a mutant derivative of this toxin. Substitution of seven different amino acid residues for Glu(15) in Css4 yielded toxin derivatives with both increased and decreased affinities for binding to neurotoxin receptor site 4 on sodium channels. Css4(E15R) is unique among this set of mutants in that it retained nearly normal binding affinity but lost its functional activity for modification of sodium channel gating in our standard electrophysiological assay for voltage sensor trapping. More detailed analysis of the functional effects of Css4(E15R) revealed weak voltage sensor trapping activity, which was very rapidly reversed upon repolarization and therefore was not observed in our standard assay of toxin effects. This partial agonist activity of Css4(E15R) is observed clearly in voltage sensor trapping assays with brief (5 ms) repolarization between the conditioning prepulse and the test pulse. The effects of Css4(E15R) are fit well by a three-step model of toxin action involving concentration-dependent toxin binding to its receptor site followed by depolarization-dependent activation of the voltage sensor and subsequent voltage sensor trapping. Because it is a partial agonist with much reduced efficacy for voltage sensor trapping, Css4(E15R) can antagonize the effects of wild-type Css4 on sodium channel activation and can prevent paralysis by Css4 when injected into mice. Our results define the first partial agonist and antagonist activities for scorpion toxins and open new avenues of research toward better understanding of the structure-function relationships for toxin action on sodium channel voltage sensors and toward

  14. Age effects on the pharmacokinetics of tityustoxin from Tityus serrulatus scorpion venom in rats

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    E.A. Nunan

    2004-03-01

    Full Text Available The pharmacokinetics of scorpion venom and its toxins has been investigated in experimental models using adult animals, although, severe scorpion accidents are associated more frequently with children. We compared the effect of age on the pharmacokinetics of tityustoxin, one of the most active principles of Tityus serrulatus venom, in young male/female rats (21-22 days old, N = 5-8 and in adult male rats (150-160 days old, N = 5-8. Tityustoxin (6 µg labeled with 99mTechnetium was administered subcutaneously to young and adult rats. The plasma concentration vs time data were subjected to non-compartmental pharmacokinetic analysis to obtain estimates of various pharmacokinetic parameters such as total body clearance (CL/F, distribution volume (Vd/F, area under the curve (AUC, and mean residence time. The data were analyzed with and without considering body weight. The data without correction for body weight showed a higher Cmax (62.30 ± 7.07 vs 12.71 ± 2.11 ng/ml, P < 0.05 and AUC (296.49 ± 21.09 vs 55.96 ± 5.41 ng h-1 ml-1, P < 0.05 and lower Tmax (0.64 ± 0.19 vs 2.44 ± 0.49 h, P < 0.05 in young rats. Furthermore, Vd/F (0.15 vs 0.42 l/kg and CL/F (0.02 ± 0.001 vs 0.11 ± 0.01 l h-1 kg-1, P < 0.05 were lower in young rats. However, when the data were reanalyzed taking body weight into consideration, the Cmax (40.43 ± 3.25 vs 78.21 ± 11.23 ng kg-1 ml-1, P < 0.05 and AUC (182.27 ± 11.74 vs 344.62 ± 32.11 ng h-1 ml-1, P < 0.05 were lower in young rats. The clearance (0.03 ± 0.002 vs 0.02 ± 0.002 l h-1 kg-1, P < 0.05 and Vd/F (0.210 vs 0.067 l/kg were higher in young rats. The raw data (not adjusted for body weight strongly suggest that age plays a pivotal role in the disposition of tityustoxin. Furthermore, our results also indicate that the differences in the severity of symptoms observed in children and adults after scorpion envenomation can be explained in part by differences in the pharmacokinetics of the toxin.

  15. THE MOUSE AS AN EXPERIMENTAL MODEL FOR TITYUS SERRULATUS SCORPION ENVENOMING

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    Mônica de Mônico Magalhães

    1998-10-01

    Full Text Available The scorpion toxin induces a number of physiological parameters alterations, as disturbance of cardiac rhythm, heart failure, shock, pancreatic hypersecretion, abortion, respiratory arrhytmias and pulmonary edema. As the purification of the venom fractions is a laborious process, one alternative for this would be the utilization of small animals. We utilized in the present study thity-six mice that received progressive doses of scorpion toxin TsTX, i.p. or i.v., and were observed for three hours or sacrificed, and the pulmonary alterations were determined by the lung-body index and by histological analysis of the lungs in order to determine if the mouse can be an esperimental model for scorpion envenomation. The data were analyzed by One Way analysis of variance with pA toxina do escorpião induz a várias alterações fisiológicas, como disturbio do ritmo cardíaco, insuficiência cardíaca, choque, hipersecreção pancreática, aborto, arritmias respiratórias e edema pulmonar. A purificação de frações do veneno é um processo trabalhoso. Como alternativa utilizam-se animais pequenos. No presente estudo utilizou-se 36 camundongos que receberam doses progressivas de toxinas do escorpião (TsTX, intraperitoneal ou intravenosa e foram observados por tres horas ou sacrificados. As alteraçòes pulmonares foram determinadas pela fórmula peso do pulmão x 100/ peso corporal e pela análise hitológica dos pulmões a fim de determinar que o camundongo pode ser um modelo experimental do envenenamento pelo escorpião. Os dados foram analizados pela análise de variância considerando-se p<0,05 indicando significancia. Os experimentos não mostraram diferença nos sinais clínicos do envenenamento comparando-se o camundongo com outros mamíferos. Os efeitos foram dose-dependente e que pela via venosa necessita-se menos quantidade para produzir as mesmas alterações. Nos aspectos histológicos pulmonares observou-se edema septal e não alveolar

  16. Scorpion toxins for the reversal of BoNT-induced paralysis.

    Science.gov (United States)

    Lowery, Colin A; Adler, Michael; Borrell, Andrew; Janda, Kim D

    2013-12-15

    The botulinum neurotoxins, characterized by their neuromuscular paralytic effects, are the most toxic proteins known to man. Due to their extreme potency, ease of production, and duration of activity, the BoNT proteins have been classified by the Centers for Disease Control as high threat agents for bioterrorism. In an attempt to discover effective BoNT therapeutics, we have pursued a strategy in which we leverage the blockade of K(+) channels that ultimately results in the reversal of neuromuscular paralysis. Towards this end, we utilized peptides derived from scorpion venom that are highly potent K(+) channel blockers. Herein, we report the synthesis of charybdotoxin, a 37 amino acid peptide, and detail its activity, along with iberiotoxin and margatoxin, in a mouse phrenic nerve hemidiaphragm assay in the absence and the presence of BoNT/A.

  17. Scorpion beta-toxins and voltage-gated sodium channels: interactions and effects.

    Science.gov (United States)

    Pedraza Escalona, Martha; Possani, Lourival D

    2013-01-01

    Scorpion beta-toxins (beta-ScTxs) modify the activity of voltage-gated sodium (Nav) channels, thereby producing neurotoxic effects in diverse organisms. For this reason, beta-ScTxs are essential tools not only for discriminating among different channel sub-types but also for studying the mechanisms of channel gating and the structure-function relationship involved in this process. This review considers both the structural and the functional implications of the beta-ScTxs after they bind to their receptor sites, in accord with their classification into a) anti-mammalian beta-ScTxs, b) anti-insect selective excitatory beta-ScTxs, c) anti-insect selective depressant beta-ScTxs and d) beta-ScTxs active on both insect and mammals Nav channels. Additionally, the molecular mechanism of toxin action by the "voltage sensor trapping" model is discussed, and the systemic effects produced by these toxins are reviewed.

  18. Antivenom reversal of biochemical alterations induced by black scorpion Heterometrus fastigiousus Couzijn venom in mice

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    MK Chaubey

    2009-01-01

    Full Text Available In the present study, Heterometrus fastigiousus venom (HFV was employed as antigen to produce species-specific scorpion antivenom (SAV in albino mice (NIH strain. To determine SAV efficacy, it was pre-incubated with 10 LD50 of HFV and then injected subcutaneously into mice. Subsequently, mortality was observed after 24 hours. Minimum effective dose (MED was 12.5 LD50 of HFV/mL of SAV. SAV effectiveness to reverse HFV-induced biochemical alterations in mice was analyzed by challenge method. Simultaneously, mice received subcutaneously 40% of 24-hour-LD50 of HFV and intravenously SAV. After four hours, changes in serum glucose, free amino acids, uric acids, pyruvic acid, cholesterol, total protein, alkaline phosphatase, acid phosphatase, lactic dehydrogenase and glutamate-pyruvate transaminase enzyme level were determined. Treatment with species-specific SAV resulted in the reversal of HFV-induced biochemical alterations.

  19. Antibacterial Activity and Toxicity of Analogs of Scorpion Venom IsCT Peptides.

    Science.gov (United States)

    de la Salud Bea, Roberto; Petraglia, Adam F; Ascuitto, Michael R; Buck, Quentin M

    2017-06-28

    Seven analogs of the natural, α-helix peptides IsCT1 and IsCT2-found in the venom of scorpion Opithancatus Madagascariensis-have been synthesized and tested to compare their antibacterial and hemolytic activity against natural peptides. In general, results show that increasing hydrophobicity by substituting positions 5 and 9 of the sequences with alanine, valine, and leucine, enhances antibacterial activity. However, this also increases hemolytic activity. The analog with an increased net positive charge from +1 to +3 produces moderate bacterial growth inhibition but also has high hemolytic activity. On the other hand, the analog with a negative net charge (-1) has low antibacterial properties but also no cytotoxicity under the tested conditions, a similar result was found for five of the seven studied analogs.

  20. A toxin to nervous, cardiac, and endocrine ERG K+ channels isolated from Centruroides noxius scorpion venom.

    Science.gov (United States)

    Gurrola, G B; Rosati, B; Rocchetti, M; Pimienta, G; Zaza, A; Arcangeli, A; Olivotto, M; Possani, L D; Wanke, E

    1999-05-01

    Toxins isolated from a variety of venoms are tools for probing the physiological function and structure of ion channels. The ether-a-go-go-related genes (erg) codify for the K+ channels (ERG), which are crucial in neurons and are impaired in human long-QT syndrome and Drosophila 'seizure' mutants. We have isolated a peptide from the scorpion Centruroides noxius Hoffmann that has no sequence homologies with other toxins, and demonstrate that it specifically inhibits (IC50=16+/-1 nM) only ERG channels of different species and distinct histogenesis. These results open up the possibility of investigating ERG channel structure-function relationships and novel pharmacological tools with potential therapeutic efficacy.

  1. Scorpion仪器主机故障及解决方法%Troubleshooting for Scorpion host

    Institute of Scientific and Technical Information of China (English)

    岩巍; 杨波; 李园园

    2012-01-01

    After introducing the structure and main functions of Scorpion host, this paper focus on analyzing the problems appeared in the field seismic operation and put forward some related solutions. Those solutions are proved to he effective for improving the production efficiency and reducing the delay time for troubleshooting in field operation.%本文介绍了Scorpion仪器主机的构成及其主要功能,重点剖析了该仪器主机各部分在野外实际应用中常见的故障,并提供了故障分析和排除的方法。有助于在野外工作现场快速解决问题,减少由于主机出现故障产生的待工时间,提高生产效率。

  2. Structure-function relationship of bifunctional scorpion toxin BmBKTxl

    Institute of Scientific and Technical Information of China (English)

    Suming Wang; Lijun Huang; Dieter Wicher; Chengwu Chi; Chenqi Xu

    2008-01-01

    As the first identified scorpion toxin active on both big conductance Ca2+-activated K+ channels (BK) and small conductance Ca2+-activated K+ channels (SK), BmBKTxl has been proposed to have two separate functional faces for two targets. To investigate this hypothesis, two double mutants,K21A-Y30A and R9A-KIlA, together with wild-type toxin were expressed in Escherichia coli. The recombinant toxins were tested on cockroach BK and rat SK2 channel for functional assay. Mutant K21A-Y30A had a dramatic loss of function on BK but retained its function on SK. Mutant R9A-KI1A did not lose function on BK or SK. These data support the two functional-face hypothesis and indicate that the BK face is on the C-terminal β-sheet.

  3. Second record of Tityus bahiensis (Scorpiones, Buthidae from Venezuela: epidemiological implications

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    L. De Sousa

    2008-01-01

    Full Text Available This work reports the second record of the scorpion Tityus bahiensis Perty from Venezuela. The specimen was found alive in a wardrobe at a hotel resort in Margarita Island, northeastern Venezuela. Morphological characterization allowed its assignment to the Tityus bahiensis population inhabiting the southernmost area of the species' geographic range, e.g. the state of São Paulo in Brazil, northern Argentina and Paraguay. The fact that the only available Venezuelan antiscorpion (anti-Tityus discrepans serum does not neutralize the effects of alpha- and beta-toxin from Tityus serrulatus venom (which resembles in composition that of T. bahiensis constitutes a warning to local clinicians confronted with envenomations by noxious species transported to Venezuela from Brazil by human agency.

  4. Full characterization of three toxins from the Androctonus amoreuxi scorpion venom.

    Science.gov (United States)

    Abbas, Najwa; Legros, Christian; Ceard, Brigitte; Belghazi, Maya; Hamon, Alain; Bougis, Pierre E; Martin-Eauclaire, Marie-France

    2009-09-15

    In this study, we have characterized the immunological and pharmacological properties of the three major alpha-type toxins from the scorpion Androctonus amoreuxi, AamH1, AamH2 and AamH3, which were previously described as putative toxins from cDNAs [Chen, T. et al., 2003. Regul. Pept. 115, 115-121]. The immunological tests (ELISA, RIA) have demonstrated that AamH1, AamH2 and AamH3 belong to the immunological groups 3 and 4 of alpha-type toxins. Analysis of the three toxin effects on currents through rat brain (rNav1.2), rat muscle (rNav1.4) and Drosophila (DmNav1) sodium channels expressed in Xenopus oocytes revealed that AamH1 and AamH2, but not AamH3, have anti-insect and anti-mammal activities and can be classified as alpha-like toxins. While AamH1 removes fast inactivation only in neuronal rNav1.2 channel and has no effect on muscular rNav1.4 channel, AamH2 affects both neuronal rNav1.2 and muscular rNav1.4 channels. AamH3 was lethal to mice by intracerebroventricular injection despite its lack of activity on the neuronal rNav1.2 channel. Finally, we have shown that the A. amoreuxi venom was better neutralized by the antiserum raised against the venom of Buthus occitanus tunetanus than by the antisera raised against scorpion venoms from the same genus Androctonus.

  5. Pathophysiological and neurobehavioral injuries in mice experimentally envenomed with Androctonus liouvillei (Pallary, 1928) scorpion venom.

    Science.gov (United States)

    El Hidan, Moulay Abdelmonaim; Touloun, Oulaid; El Hiba, Omar; Boumezzough, Ali

    2016-01-01

    The genus Androctonus is represented by 7 scorpion species in Morocco. All studies conducted on the characterization of Androctonus species venom are limited to Androctonus mauritanicus. However, there is other species which arouses also interest of scientists due to their high toxicity. Thus, we chose to assess the toxic effect of Androctonus liouvillei venom by sublethal injection and the effects on some vital organs, by a histological and a biochemical tools. In addition, we aimed to characterize the neurobehavioral impairments, in Swiss mice, 3h, 6h and 12h following envenomation. The LD50 of A. liouvillei scorpion venom was found to be 0.29mg/kg by subcutaneous injection route. Venom administration induced glomerular destruction and disorganization in the Bowman's spac. Examination of lungs showed a remarkable focal rupture of the alveolar structure and intra-alveolar hemorrhage. Concurrently, there was a significant enhancement in the serum enzymes levels of AST, ALT, CPK and LDH, and a high level of glucose and creatinine. Proteinuria was also observed. Regarding the behavioral effects we noted a hypoactivity and anxiogenic-like effect, manifested by an increased time spent in the open arms in groups tested 30min and 12h after the injection. Concomitantly with an increased immobility time in the tail suspension test. The present finding show an obvious profound neuromodulatory effect of A. liouvillei venom manifested by an impaired neurobehavioral and physiological patterns in mice that may in part explain the toxic effect of the venom in human as one of the potent death agents.

  6. Genomic and structural characterization of Kunitz-type peptide LmKTT-1a highlights diversity and evolution of scorpion potassium channel toxins.

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    Zongyun Chen

    Full Text Available BACKGROUND: Recently, a new subfamily of long-chain toxins with a Kunitz-type fold was found in scorpion venom glands. Functionally, these toxins inhibit protease activity and block potassium channels. However, the genomic organization and three-dimensional (3-D structure of this kind of scorpion toxin has not been reported. PRINCIPAL FINDINGS: Here, we characterized the genomic organization and 3-D nuclear magnetic resonance structure of the scorpion Kunitz-type toxin, LmKTT-1a, which has a unique cysteine pattern. The LmKTT-1a gene contained three exons, which were interrupted by two introns located in the mature peptide region. Despite little similarity to other Kunitz-type toxins and a unique pattern of disulfide bridges, LmKTT-1a possessed a conserved Kunitz-type structural fold with one α-helix and two β-sheets. Comparison of the genomic organization, 3-D structure, and functional data of known toxins from the α-KTx, β-KTx, γ-KTx, and κ-KTx subfamily suggested that scorpion Kunitz-type potassium channel toxins might have evolved from a new ancestor that is completely different from the common ancestor of scorpion toxins with a CSα/β fold. Thus, these analyses provide evidence of a new scorpion potassium channel toxin subfamily, which we have named δ-KTx. CONCLUSIONS/SIGNIFICANCE: Our results highlight the genomic, structural, and evolutionary diversity of scorpion potassium channel toxins. These findings may accelerate the design and development of diagnostic and therapeutic peptide agents for human potassium channelopathies.

  7. Cloning, expression, and pharmacological activity of BmK AS, an active peptide from scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Shao, Jian-Hua; Wang, Yue-Qiu; Wu, Xiao-Yan; Jiang, Rui; Zhang, Rong; Wu, Chun-Fu; Zhang, Jing-Hai

    2008-01-01

    BmK AS is a beta long-chain scorpion peptide from the venom of Buthus martensii Karsch (BmK). It was efficiently expressed as a soluble and functional peptide in Escherichia coli, and purified by metal chelating chromatography. About 4.2 mg/l purified recombinant BmK AS could be obtained. The recombinant BmK AS maintained a similar analgesic activity to the natural one in both the mouse-twisting test and hot-plate procedure. It also exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. BmK AS is the first long-chain scorpion peptide reported to have antimicrobial activity, and is a valuable molecular scaffold for pharmacological research.

  8. Functional analysis of the alpha-neurotoxin, BmalphaTX14, derived from the Chinese scorpion, Buthus martensii Karsch.

    Science.gov (United States)

    Wang, Kun; Yin, Shi-Jin; Lu, Meng; Yi, Hong; Dai, Chao; Xu, Xiu-Jing; Cao, Zhi-Jian; Wu, Ying-Liang; Li, Wen-Xin

    2006-11-01

    The gene encoding the BmalphaTX14 (alpha-neurotoxin TX14) protein, derived from the cDNA library of the Chinese scorpion Buthus martensii Karsch, was expressed in Pichia pastoris. The recombinant protein was purified by metal chelate affinity chromatography and gel filtration chromatography. Using patch-clamp technique, electrophysiological activity of rBmalphaTX14 was identified. In the neurons isolated from mice trigeminal root ganglion, the Na+ current amplitude was reduced by 80% under whole cell patch-clamp recording. There were no apparent modifications to the gating mechanism in the presence of rBmalphaTX14. Although BmalphaTX14 shared a high amino acid sequence similarity with other typical alpha-toxins, it has different effects on neurons. Further electrophysiological analysis suggested that rBmalphaTX14 selectively blocked Na+ channels and is a member of a new group of scorpion toxins.

  9. Cloning and molecular characterization of BumaMPs1, a novel metalloproteinases from the venom of scorpion Buthus martensi Karsch.

    Science.gov (United States)

    Xia, Xichao; Ma, Yuhong; Xue, Shipeng; Wang, Aimei; Tao, Junliang; Zhao, Yan; Zhang, Qingyuan; Liu, Rongzhi; Lu, Shaoe

    2013-12-15

    Scorpion venoms metalloproteinase is involved in a number of important biological, physiological and pathophysiological processes. In this work, a complete sequence of metalloproteinase was first obtained from venom of scorpion Buthus martensi and named as BumaMPs1. BumaMPs1 has 393 amino acid residues containing with a molecular mass of 44.53 kDa, showing an isoelectric point of 5.66. The primary sequence analysis indicated that the BumaMPs1 contains a zinc-binding motif (HELGHNLGISH), methionine-turn motif (YIM), disintegrin-like domain (ETCD) and N-glycosylation site. The multiple alignment of its deduced amino acid sequence and those of other metalloproteinase showed a high structural similarly, mainly among class reprolysin proteases. The phylogenetic analysis showed early divergence and independent evolution of BumaMPs1 from other metalloproteinase.

  10. Structure-function relationships in scorpion neurotoxins. Identification of the supperreactive lysine residue in toxin I of Androctonus australis Hector.

    Science.gov (United States)

    Sampieri, F; Habersetzer-Rochat, C

    1978-07-21

    In a previous article (Habersetzer-Rochat, C. and Sampieri, R. (1976) Biochemistry 15, 2254--2261) it was demonstrated that the toxin I of the North African Scorpion Androctonus australis Hector was inactivated after reaction with iodoacetate; the toxicity loss in mice was correlated with the carboxymethylation of one superreactive residue. In the present work, alkylation of toxin I was performed with iodo[14C]-acetate. Hence, it was possible, after reduction, S-methylation and chymotryptic hydrolysis of this toxin, to isolate the peptide containing the labelled lysine residue. By automatic Edman degradation, this residue was identified as being the penultimate lysine at position 56 in the primary sequence. Comparison of three primary structures of scorpion neurotoxins and comparison in different kinds of activity seem to indicate that this lysine residue is mainly important for toxicity in mice.

  11. Experimental Tityus serrulatus scorpion envenomation: age- and sex-related differences in symptoms and mortality in mice

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    Pucca MB

    2011-01-01

    Full Text Available Among the various methods for evaluating animal venom toxicity, the calculation of the median lethal dose (LD50 is the most widely used. Although different protocols can be used to calculate the LD50, the source of the venom and the method of extraction, as well as the strain, age, and sex of the animal model employed, should be taken into consideration. The objective of the present study was to evaluate the influence of sex and age on the toxicity of Tityus serrulatus scorpion venom in Swiss mice. Although the symptoms of envenomation were similar in male and female animals, female mice proved to be more resistant to the venom. In females, age had no impact on the susceptibility to scorpion envenomation. Male mice were more sensitive to T. serrulatus venom. Moreover, in males, age was an important parameter since sensitivity to the venom increased with age.

  12. Scorpion (Androctonus bicolor venom exhibits cytotoxicity and induces cell cycle arrest and apoptosis in breast and colorectal cancer cell lines

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    Abdulrahman K Al-Asmari

    2016-01-01

    Full Text Available Objectives: The defective apoptosis is believed to play a major role in the survival and proliferation of neoplastic cells. Hence, the induction of apoptosis in cancer cells is one of the targets for cancer treatment. Researchers are considering scorpion venom as a potent natural source for cancer treatment because it contains many bioactive compounds. The main objective of the current study is to evaluate the anticancer property of Androctonus bicolor scorpion venom on cancer cells. Materials and Methods: Scorpions were milked by electrical stimulation of telsons and lyophilized. The breast (MDA-MB-231 and colorectal (HCT-8 cancer cells were maintained in appropriate condition. The venom cytotoxicity was assessed by 3-(4,5-di-methylthiazol-2-yl-2,5-diphenyl-2H-tetrazolium bromide assay, and the cellular and nuclear changes were studied with propidium iodide and 4′,6-diamidino-2-phenylindole stain, respectively. The cell cycle arrest was examined using muse cell analyzer. Results: The A. bicolor venom exerted cytotoxic effects on MDA-MB-231 and HCT-8 cells in a dose- and duration-dependent manner and induced apoptotic cell death. The treatment with this venom arrests the cancer cells in G0/G1 phase of cell cycle. Conclusions: The venom selectively induces the rate of apoptosis in MDA-MB-231 and HCT-8 cells as reflected by morphological and cell cycle studies. To the best of our knowledge, this is the first scientific evidence demonstrating the induction of apoptosis and cell cycle arrest by A. bicolor scorpion venom.

  13. Scorpion (Androctonus bicolor) venom exhibits cytotoxicity and induces cell cycle arrest and apoptosis in breast and colorectal cancer cell lines

    Science.gov (United States)

    Al-Asmari, Abdulrahman K.; Riyasdeen, Anvarbatcha; Abbasmanthiri, Rajamohamed; Arshaduddin, Mohammed; Al-Harthi, Fahad Ali

    2016-01-01

    Objectives: The defective apoptosis is believed to play a major role in the survival and proliferation of neoplastic cells. Hence, the induction of apoptosis in cancer cells is one of the targets for cancer treatment. Researchers are considering scorpion venom as a potent natural source for cancer treatment because it contains many bioactive compounds. The main objective of the current study is to evaluate the anticancer property of Androctonus bicolor scorpion venom on cancer cells. Materials and Methods: Scorpions were milked by electrical stimulation of telsons and lyophilized. The breast (MDA-MB-231) and colorectal (HCT-8) cancer cells were maintained in appropriate condition. The venom cytotoxicity was assessed by 3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay, and the cellular and nuclear changes were studied with propidium iodide and 4’,6-diamidino-2-phenylindole stain, respectively. The cell cycle arrest was examined using muse cell analyzer. Results: The A. bicolor venom exerted cytotoxic effects on MDA-MB-231 and HCT-8 cells in a dose- and duration-dependent manner and induced apoptotic cell death. The treatment with this venom arrests the cancer cells in G0/G1 phase of cell cycle. Conclusions: The venom selectively induces the rate of apoptosis in MDA-MB-231 and HCT-8 cells as reflected by morphological and cell cycle studies. To the best of our knowledge, this is the first scientific evidence demonstrating the induction of apoptosis and cell cycle arrest by A. bicolor scorpion venom. PMID:27721540

  14. Modulation of human Nav1.7 channel gating by synthetic α-scorpion toxin OD1 and its analogs

    OpenAIRE

    2015-01-01

    Nine different voltage-gated sodium channel isoforms are responsible for inducing and propagating action potentials in the mammalian nervous system. The Nav1.7 channel isoform plays an important role in conducting nociceptive signals. Specific mutations of this isoform may impair gating behavior of the channel resulting in several pain syndromes. In addition to channel mutations, similar or opposite changes in gating may be produced by spider and scorpion toxins binding to different parts of ...

  15. Cardiac disorders and mode of action of the Egyptian scorpion venom Androctonus bicolor on isolated toad’s heart

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    Mohamed A. Abdel-Rahman

    2015-10-01

    Full Text Available Scorpion venom is a complex mixture of components with various pharmacological and toxicological effects. It is characterized by the presence of a large number of toxins that specifically interact with ion channels of excitable cells. The Egyptian scorpion Androctonus bicolor belongs to the family of Buthidae and until now no information is available about the effect of its venom on cardiac muscles. Using an in vitro approach, cardiotoxicity and mode of action of A. bicolor venom on isolated toad’s heart were investigated. Direct application of scorpion venom (0.5 μg/ml into isolated toad’s heart induced a remarkable bradycardia concomitant with a protraction in the conduction time (P–R interval. In the meantime, a significant increase in the R-wave amplitude (ventricular contraction was noticed after 5 min of venom perfusion. Various cases of cardiac disorders were recorded such as sinus arrhythmias, ectopic beats and different degrees of heart block. Through using different autonomic and ion channel blockers, the possible mechanism of action of A. bicolor venom on isolated toad’s heart was revealed. The application of both atropine (4 μg/ml and verapamil (5 μg/ml could not alleviate the pronounced negative chronotropic and positive inotropic effects. Meanwhile, a significant decrease in the R-wave amplitude was observed after propranolol (5 μg/ml application. In conclusion, our findings indicate that the venom of A. bicolor directly influenced the cardiac electrical activity of toads through β-adrenergic receptors. The direct effect of this venom on cardiac tissues may significantly contribute in the development of several cardiotoxic effects following scorpion sting.

  16. Expression, renaturation and functional analysis of an excitatory insect-specific toxin from scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Li, Chong; Liu, Wei; Bossmans, Frank; Zhu, Rong-Huan; Tytgat, Jan; Wang, Da-Cheng

    2005-10-01

    The cDNA of BmK IT-AP, an excitatory insect toxin from the scorpion Buthus martensi Karsch that has an analgesic effect on mammalian cells, was expressed in E. coli in the form of an inclusion body. Following denaturation and reduction, the recombinant protein was renatured and purified by liquid chromatography. The authenticity of the recombinant product was confirmed by bioassay and its electrophysiological effect on insect sodium channel.

  17. Purification, characterization, and bioactivity of a new analgesic-antitumor peptide from Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Shao, Jian-Hua; Cui, Yong; Zhao, Ming-Yi; Wu, Chun-Fu; Liu, Yan-Feng; Zhang, Jing-Hai

    2014-03-01

    Scorpion venoms are complex mixtures of dozens or even hundreds of distinct proteins, many of which have diverse bioactivities. In this study, after bioassay-driven chromatographic purification, a new dual-function peptide with analgesic and antitumor activities was isolated and designated BmK AGAP-SYPU2. The first 12 amino acid residues were sequenced with Edman degradation. The cDNA was cloned by using rapid amplification of cDNA ends from the cDNA pool from scorpion glands. The amino acid sequence of BmK AGAP-SYPU2 was then deduced, and is consistent with the molecular mass measured with MALDI-TOF-MS. A preliminary pharmacological analysis revealed the following: in the dose-effect curve plotted with the mouse-twisting test, BmK AGAP-SYPU2 showed analgesic activity with an ED50 value of 1.42 mg/kg; in the time-effect curves plotted with a hot-plate procedure, BmK AGAP-SYPU2 had similar effects to those of the painkiller morphine, except for its longer duration. BmK AGAP-SYPU2 also showed antitumor activity against Ehrlich ascites tumor and S-180 fibrosarcoma models in vivo. Sequence alignment and homology modeling showed that BmK AGAP-SYPU2 is highly conserved relative to other scorpion α-toxins. However, a few different amino acids endow it with unique molecular properties, which may be responsible for its specific bioactivities. BmK AGAP-SYPU2, a new scorpion neurotoxin with dual functions, is a potential candidate drug amenable to exploitation and modification.

  18. Characterization of Am IT, an anti-insect β-toxin isolated from the venom of scorpion Androctonus mauretanicus.

    Science.gov (United States)

    Oukkache, Naoual; ElJaoudi, Rachid; Chgoury, Fatima; Rocha, Marisa Teixeira; Sabatier, Jean-Marc

    2015-06-25

    In the present study, a 'novel' toxin, called Am IT from the venom of scorpion Androctonus mauretanicus is isolated and characterized. A detailed analysis of the action of Am IT on insect axonal sodium currents is reported. Am IT was purified through gel filtration followed by C18 reversed-phase HPLC. Toxicity of Am IT in vivo was assessed on male German cockroach (Blattella germanica) larvae and C57/BL6 mice. Cross-reactivity of Am IT with two β-toxins was evidenced using (125)I-iodinated toxin-based radioimmunoassays with synaptosomal preparations from rat brain. The complete amino acid sequence of Am IT was finally determined by Edman sequencing. Am IT was observed to compete with AaH IT4 purified from the venom of scorpion Androctonus australis in binding assays. It was recognized by an antibody raised against a β-type toxin, which indicated some structural similarity with β-toxins (or related toxin family). The 'novel' toxin exhibited dual activity since it competed with anti-mammal toxins in binding assays as well as showed contracting activity to insect. The toxin competed with radio-labeled β-toxin Css IV by binding to Na(+) channels of rat brain synaptosomes. Analysis of toxin amino acid sequences showed that Am IT shares high structural identity (92%) with AaH IT4. In conclusion, Am IT not only reveals an anti-insect compound properties secreted by 'Old World' scorpions, paralyzing insect larvae by binding to Na(+) channels on larvae's nerve-cell membranes, but also exerts toxic activity in mice, which is similar to anti-mammal toxins from 'New World' scorpions (North and South Americas). Therefore, Am IT appears to be structurally and functionally similar to AaH IT4.

  19. Enzymatic properties of venoms from Brazilian scorpions of Tityus genus and the neutralisation potential of therapeutical antivenoms.

    Science.gov (United States)

    Venancio, Emerson J; Portaro, Fernanda C V; Kuniyoshi, Alexandre K; Carvalho, Daniela Cajado; Pidde-Queiroz, Giselle; Tambourgi, Denise V

    2013-07-01

    Tityus scorpion stings are an important public health problem in Brazil, where the incidence of such stings exceeds the incidence of the health problems caused by other venomous animals, including snakes. In this study, we have analysed specific enzymatic activities of the venom from the Brazilian scorpions of Tityus genus, i.e., Tityus serrulatus, Tityus bahiensis and Tityus stigmurus. The data presented here revealed that Tityus spp. venoms exhibited significant hyaluronidase activity but no phospholipase activity. All the venom samples exhibited the ability to hydrolyse Abz-FLRRV-EDDnp and dynorphin 1-13 substrates. These activities were inhibited by 1,10-phenanthroline but not by PMSF, indicating the presence of metalloproteinases in the Tityus spp. venoms. The venom peptidase activity on Abz-FLRRV-EDDnp and on dynorphin 1-13 was partially inhibited by therapeutic Brazilian anti-scorpion and anti-arachnidic antivenoms. Dynorphin 1-13 (YGGFLRRIRPKLK) contains two scissile bonds between the residues Leu-Arg and Arg-Arg that are susceptible to cleavage by the Tityus venom metallopeptidase(s). Their cleavage releases leu-enkephalin, an important bioactive peptide. The detection of metalloproteinase(s) with specificity for both dynorphin 1-13 degradation and leu-enkephalin releasing can be important for the mechanistic understanding of hypotension and bradycardia induction in cases of scorpion stings, whereas hyaluronidases might contribute to the diffusion of the toxins present in these venoms. Furthermore, the limited inhibition of the toxic enzymatic activities by commercial antivenoms illustrates the necessity of improvements in current antivenom preparation.

  20. Arachnids of medical importance in Brazil: main active compounds present in scorpion and spider venoms and tick saliva.

    Science.gov (United States)

    Cordeiro, Francielle A; Amorim, Fernanda G; Anjolette, Fernando A P; Arantes, Eliane C

    2015-01-01

    Arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). Many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. These animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. Several protein and non-protein compounds present in the venom and saliva of these animals are responsible for symptoms observed in envenoming, exhibiting neurotoxic, dermonecrotic and hemorrhagic activities. The phylogenomic analysis from the complementary DNA of single-copy nuclear protein-coding genes shows that these animals share some common protein families known as neurotoxins, defensins, hyaluronidase, antimicrobial peptides, phospholipases and proteinases. This indicates that the venoms from these animals may present components with functional and structural similarities. Therefore, we described in this review the main components present in spider and scorpion venom as well as in tick saliva, since they have similar components. These three arachnids are responsible for many accidents of medical relevance in Brazil. Additionally, this study shows potential biotechnological applications of some components with important biological activities, which may motivate the conducting of further research studies on their action mechanisms.

  1. Convergent evolution in the antennae of a cerambycid beetle, Onychocerus albitarsis, and the sting of a scorpion

    Science.gov (United States)

    Berkov, Amy; Rodríguez, Nelson; Centeno, Pedro

    2008-03-01

    Venom-injecting structures have arisen independently in unrelated arthropods including scorpions, spiders, centipedes, larval owlflies and antlions, and Hymenoptera (wasps, ants, and bees). Most arthropods use venom primarily as an offensive weapon to subdue prey, and only secondarily in defense against enemies. Venom is injected by biting with fangs or stinging with a specialized hypodermic structure used exclusively for the delivery of venom (usually modified terminal abdominal segments). A true sting apparatus, previously known only in scorpions and aculeate wasps, is now known in a third group. We here report the first known case of a cerambycid beetle using its antennae to inject a secretion that causes cutaneous and subcutaneous inflammation in humans. Scanning electron microscopy revealed that the terminal antennal segment of Onychocerus albitarsis (Pascoe) has two pores opening into channels leading to the tip through which the secretion is delivered. This is a novel case of convergent evolution: The delivery system is almost identical to that found in the stinger of a deadly buthid scorpion.

  2. Solution structure of BmKalphaTx11, a toxin from the venom of the Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Zhu, Jing; Tong, Xiaotian; Cao, Chunyang; Wu, Gong; Zhang, Naixia; Wu, Houming

    2010-01-01

    The solution structure of BmKalphaTx11 presented by this paper is distinctive from any other structures of wide-type scorpion alpha-toxins reported so far, for its trans-9,10 peptide bond conformation is accompanied by 'protruding' topology of the 'NC-domain'. The orientation of the C-tail of BmKalphaTx11 is obviously different from that of classical alpha-toxins (e.g., AaH2, BmK-M8), despite the fact that they share common trans conformation of peptide bond between residues 9 and 10. Accordingly, there must be other structural factors dominating the orientation of the C-tail except the conformation of peptide bond 9-10. Our study reveals that residues at position 58 play an important role in it, and different type of residues at this position (e.g., Lys, Arg, Met, Ile) result in different spatial relationship between the C-terminus and the 'five-residue-turn' and then different topology of the 'NC-domain', therefore residues at position 58 are believed to function as structure and bioactivity switch for specificity of scorpion alpha-toxins. The mechanism for stabilizing the geometry of the 'NC-domain' in wide-type scorpion alpha-toxins is also discussed.

  3. A Combinational Strategy upon RNA Sequencing and Peptidomics Unravels a Set of Novel Toxin Peptides in Scorpion Mesobuthus martensii

    Directory of Open Access Journals (Sweden)

    Ning Luan

    2016-10-01

    Full Text Available Scorpion venom is deemed to contain many toxic peptides as an important source of natural compounds. Out of the two hundred proteins identified in Mesobuthus martensii (M. martensii, only a few peptide toxins have been found so far. Herein, a combinational approach based upon RNA sequencing and Liquid chromatography-mass spectrometry/mass spectrometry (LC MS/MS was employed to explore the venom peptides in M. martensii. A total of 153 proteins were identified from the scorpion venom, 26 previously known and 127 newly identified. Of the novel toxins, 97 proteins exhibited sequence similarities to known toxins, and 30 were never reported. Combining peptidomic and transcriptomic analyses, the peptide sequence of BmKKx1 was reannotated and four disulfide bridges were confirmed within it. In light of the comparison of conservation and variety of toxin amino acid sequences, highly conserved and variable regions were perceived in 24 toxins that were parts of two sodium channel and two potassium channel toxins families. Taking all of this evidences together, the peptidomic analysis on M. martensii indeed identified numerous novel scorpion peptides, expanded our knowledge towards the venom diversity, and afforded a set of pharmaceutical candidates.

  4. Structural and Functional Elucidation of Peptide Ts11 Shows Evidence of a Novel Subfamily of Scorpion Venom Toxins

    Science.gov (United States)

    Cremonez, Caroline M.; Maiti, Mohitosh; Peigneur, Steve; Cassoli, Juliana Silva; Dutra, Alexandre A. A.; Waelkens, Etienne; Lescrinier, Eveline; Herdewijn, Piet; de Lima, Maria Elena; Pimenta, Adriano M. C.; Arantes, Eliane C.; Tytgat, Jan

    2016-01-01

    To date, several families of peptide toxins specifically interacting with ion channels in scorpion venom have been described. One of these families comprise peptide toxins (called KTxs), known to modulate potassium channels. Thus far, 202 KTxs have been reported, belonging to several subfamilies of KTxs (called α, β, γ, κ, δ, and λ-KTxs). Here we report on a previously described orphan toxin from Tityus serrulatus venom, named Ts11. We carried out an in-depth structure-function analysis combining 3D structure elucidation of Ts11 and electrophysiological characterization of the toxin. The Ts11 structure is highlighted by an Inhibitor Cystine Knot (ICK) type scaffold, completely devoid of the classical secondary structure elements (α-helix and/or β-strand). This has, to the best of our knowledge, never been described before for scorpion toxins and therefore represents a novel, 6th type of structural fold for these scorpion peptides. On the basis of their preferred interaction with voltage-gated K channels, as compared to all the other targets tested, it can be postulated that Ts11 is the first member of a new subfamily, designated as ε-KTx. PMID:27706049

  5. OcyKTx2, a new K⁺-channel toxin characterized from the venom of the scorpion Opisthacanthus cayaporum.

    Science.gov (United States)

    Schwartz, Elisabeth F; Bartok, Adam; Schwartz, Carlos Alberto; Papp, Ferenc; Gómez-Lagunas, Froylan; Panyi, Gyorgy; Possani, Lourival D

    2013-08-01

    Opisthacanthus cayaporum belongs to the Liochelidae family, and the scorpions from this genus occur in southern Africa, Central America and South America and, therefore, can be considered a true Gondwana heritage. In this communication, the isolation, primary structure characterization, and K⁺-channel blocking activity of new peptide from this scorpion venom are reported. OcyKTx2 is a 34 amino acid long peptide with four disulfide bridges and molecular mass of 3807 Da. Electrophysiological assays conducted with pure OcyKTx2 showed that this toxin reversibly blocks Shaker B K⁺-channels with a Kd of 82 nM, and presents an even better affinity toward hKv1.3, blocking it with a Kd of ∼18 nM. OcyKTx2 shares high sequence identity with peptides belonging to subfamily 6 of α-KTxs that clustered very closely in the phylogenetic tree included here. Sequence comparison, chain length and number of disulfide bridges analysis classify OcyKTx2 into subfamily 6 of the α-KTx scorpion toxins (systematic name, α-KTx6.17).

  6. Purification and cDNA cloning of a novel neurotoxic peptide (Acra3) from the scorpion Androctonus crassicauda.

    Science.gov (United States)

    Caliskan, Figen; García, Blanca I; Coronas, Fredy I V; Restano-Cassulini, Rita; Korkmaz, Ferhan; Sahin, Yalcin; Corzo, Gerardo; Possani, Lourival D

    2012-09-01

    Androctonus crassicauda is one of the Southeastern Anatolian scorpions of Turkey with ethno-medical and toxicological importance. Two toxic peptides (Acra1 and Acra2) were isolated and characterized from the venom of this scorpion. In this communication, the isolation of an additional toxin (Acra3) by chromatographic separations (HPLC and TSK-gel sulfopropyl) and its chemical and functional characterization is reported. Acra3 is a 7620Da molecular weight peptide, with 66 amino acid residues crosslinked by four disulfide bridges. The gene coding for this peptide was cloned and sequenced. Acra3 is anticipated to undergo post-translational modifications at the C-terminal region, having an amidated serine as last residue. Injection of Acra3 induces severe neurotoxic events in mice, such as: excitability and convulsions, leading to the death of the animals within a few minutes after injection. Electrophysiological assays conducted with pure Acra3, using cells that specifically expressed sodium channels (Nav1.1-Nav1.6) showed no clear effect. The exact molecular target of Acra3 remained undiscovered, similar to three other scorpion peptides that clustered very closely in the phylogenetic tree included here. The exact target of these four peptides is not very clear.

  7. Modulation of human Nav1.7 channel gating by synthetic α-scorpion toxin OD1 and its analogs.

    Science.gov (United States)

    Motin, Leonid; Durek, Thomas; Adams, David J

    2016-01-01

    Nine different voltage-gated sodium channel isoforms are responsible for inducing and propagating action potentials in the mammalian nervous system. The Nav1.7 channel isoform plays an important role in conducting nociceptive signals. Specific mutations of this isoform may impair gating behavior of the channel resulting in several pain syndromes. In addition to channel mutations, similar or opposite changes in gating may be produced by spider and scorpion toxins binding to different parts of the voltage-gated sodium channel. In the present study, we analyzed the effects of the α-scorpion toxin OD1 and 2 synthetic toxin analogs on the gating properties of the Nav1.7 sodium channel. All toxins potently inhibited channel inactivation, however, both toxin analogs showed substantially increased potency by more than one order of magnitude when compared with that of wild-type OD1. The decay phase of the whole-cell Na(+) current was substantially slower in the presence of toxins than in their absence. Single-channel recordings in the presence of the toxins revealed that Na(+) current inactivation slowed due to prolonged flickering of the channel between open and closed states. Our findings support the voltage-sensor trapping model of α-scorpion toxin action, in which the toxin prevents a conformational change in the domain IV voltage sensor that normally leads to fast channel inactivation.

  8. Scorpion Venom Heat-Resistant Peptide Attenuates Glial Fibrillary Acidic Protein Expression via c-Jun/AP-1.

    Science.gov (United States)

    Cao, Zhen; Wu, Xue-Fei; Peng, Yan; Zhang, Rui; Li, Na; Yang, Jin-Yi; Zhang, Shu-Qin; Zhang, Wan-Qin; Zhao, Jie; Li, Shao

    2015-11-01

    Scorpion venom has been used in the Orient to treat central nervous system diseases for many years, and the protein/peptide toxins in Buthus martensii Karsch (BmK) venom are believed to be the effective components. Scorpion venom heat-resistant peptide (SVHRP) is an active component of the scorpion venom extracted from BmK. In a previous study, we found that SVHRP could inhibit the formation of a glial scar, which is characterized by enhanced glial fibrillary acidic protein (GFAP) expression, in the epileptic hippocampus. However, the cellular and molecular mechanisms underlying this process remain to be clarified. The results of the present study indicate that endogenous GFAP expression in primary rat astrocytes was attenuated by SVHRP. We further demonstrate that the suppression of GFAP was primarily mediated by inhibiting both c-Jun expression and its binding with AP-1 DNA binding site and other factors at the GFAP promoter. These results support that SVHRP contributes to reducing GFAP at least in part by decreasing the activity of the transcription factor AP-1. In conclusion, the effects of SVHRP on astrocytes with respect to the c-Jun/AP-1 signaling pathway in vitro provide a practical basis for studying astrocyte activation and inhibition and a scientific basis for further studies of traditional medicine.

  9. Unique scorpion toxin with a putative ancestral fold provides insight into evolution of the inhibitor cystine knot motif

    Science.gov (United States)

    Smith, Jennifer J.; Hill, Justine M.; Little, Michelle J.; Nicholson, Graham M.; King, Glenn F.; Alewood, Paul F.

    2011-01-01

    The three-disulfide inhibitor cystine knot (ICK) motif is a fold common to venom peptides from spiders, scorpions, and aquatic cone snails. Over a decade ago it was proposed that the ICK motif is an elaboration of an ancestral two-disulfide fold coined the disulfide-directed β-hairpin (DDH). Here we report the isolation, characterization, and structure of a novel toxin [U1-liotoxin-Lw1a (U1-LITX-Lw1a)] from the venom of the scorpion Liocheles waigiensis that is the first example of a native peptide that adopts the DDH fold. U1-LITX-Lw1a not only represents the discovery of a missing link in venom protein evolution, it is the first member of a fourth structural fold to be adopted by scorpion-venom peptides. Additionally, we show that U1-LITX-Lw1a has potent insecticidal activity across a broad range of insect pest species, thereby providing a unique structural scaffold for bioinsecticide development. PMID:21670253

  10. Unique scorpion toxin with a putative ancestral fold provides insight into evolution of the inhibitor cystine knot motif.

    Science.gov (United States)

    Smith, Jennifer J; Hill, Justine M; Little, Michelle J; Nicholson, Graham M; King, Glenn F; Alewood, Paul F

    2011-06-28

    The three-disulfide inhibitor cystine knot (ICK) motif is a fold common to venom peptides from spiders, scorpions, and aquatic cone snails. Over a decade ago it was proposed that the ICK motif is an elaboration of an ancestral two-disulfide fold coined the disulfide-directed β-hairpin (DDH). Here we report the isolation, characterization, and structure of a novel toxin [U(1)-liotoxin-Lw1a (U(1)-LITX-Lw1a)] from the venom of the scorpion Liocheles waigiensis that is the first example of a native peptide that adopts the DDH fold. U(1)-LITX-Lw1a not only represents the discovery of a missing link in venom protein evolution, it is the first member of a fourth structural fold to be adopted by scorpion-venom peptides. Additionally, we show that U(1)-LITX-Lw1a has potent insecticidal activity across a broad range of insect pest species, thereby providing a unique structural scaffold for bioinsecticide development.

  11. Clinical consequences of Tityus bahiensis and Tityus serrulatus scorpion stings in the region of Campinas, southeastern Brazil.

    Science.gov (United States)

    Bucaretchi, Fábio; Fernandes, Luciane C R; Fernandes, Carla B; Branco, Maíra M; Prado, Camila C; Vieira, Ronan J; De Capitani, Eduardo M; Hyslop, Stephen

    2014-10-01

    Scorpion stings account for most envenomations by venomous animals in Brazil. A retrospective study (1994-2011) of the clinical consequences of Tityus scorpion stings in 1327 patients treated at a university hospital in Campinas, southeastern Brazil, is reported. The clinical classification, based on outcome, was: dry sting (no envenoming), class I (only local manifestations), class II (systemic manifestations), class III (life-threatening manifestations, such as shock and/or cardiac failure requiring inotropic/vasopressor agents, and/or respiratory failure), and fatal. The median patient age was 27 years (interquartile interval = 15-42 years). Scorpions were brought for identification in 47.2% of cases (Tityus bahiensis 27.7%; Tityus serrulatus 19.5%). Sting severity was classified and each accounted for the following percentage of cases: dry stings - 3.4%, class I - 79.6%, class II - 15.1%, class III - 1.8% and fatal - 0.1%. Pain was the primary local manifestation (95.5%). Systemic manifestations such as vomiting, agitation, sweating, dyspnea, bradycardia, tachycardia, tachypnea, somnolence/lethargy, cutaneous paleness, hypothermia and hypotension were detected in class II or class III + fatal groups, but were significantly more frequent in the latter group. Class III and fatal cases occurred only in children <15 years old, with scorpions being identified in 13/25 cases (T. serrulatus, n = 12; T. bahiensis, n = 1). Laboratory blood abnormalities (hyperglycemia, hypokalemia, leukocytosis, elevations in serum total CK, CK-MB and troponin T, bicarbonate consumption and an increase in base deficit and blood lactate), electrocardiographic changes (ST segment) and echocardiographic alterations (ventricular ejected fraction <54%) were frequently detected in class III patients. Seventeen patients developed pulmonary edema, 16 had cardiac failure and seven had cardiogenic shock. These results indicate that most scorpion stings involved only local manifestations

  12. Design and expression of recombinant toxins from Mexican scorpions of the genus Centruroides for production of antivenoms.

    Science.gov (United States)

    Jiménez-Vargas, J M; Quintero-Hernández, V; González-Morales, L; Ortiz, E; Possani, L D

    2017-03-15

    This manuscript describes the design of plasmids containing the genes coding for four main mammalian toxins of scorpions from the genus Centruroides (C.) of Mexico. The genes that code for toxin 2 of C. noxius (Cn2), toxin 2 from C. suffusus (Css2) and toxins 1 and 2 from C. limpidus (Cll1 and Cll2) were included into individual plasmids carrying the genetic construction for expression of fusion proteins containing a leader peptide (pelB) that directs the expressed protein to the bacterial periplasm, a carrier protein (thioredoxin), the cleavage site for enterokinase, the chosen toxin and a poly-histidine tag (6xHis-tag) for purification of the hybrid protein by immobilized metal ion affinity chromatography after expression in Escherichia coli strain BL21 (DE3). The purified hybrid proteins containing the recombinant toxins (abbreviated Thio-EK-Toxin) were used for immunization of three independent groups of ten mice and four rabbits. Challenging the first group of mice, immunized with recombinant Thio-EK-Css2, with three median lethal doses (LD50) of C. suffusus soluble venom resulted in the survival of all the test animals without showing intoxication symptoms. All control mice (none immunized) died. Similar results were obtained with mice previously immunized with Thio-EK-Cn2 and challenged with C. noxius venom. The third group of mice immunized with both Thio-EK-Cll1 and Thio-EK-Cll2 showed an 80% survival ratio when challenged with only one LD50 of C. limpidus venom, all showing symptoms of intoxication. The sera from rabbits immunized with a combination of the four recombinant toxins were collected separately and used to assess their neutralization capacity in vitro (pre-incubating the serum with the respective scorpion venom and injecting the mixture into mice), using six mice for each serum/venom combination tested. The venoms from the six most dangerous scorpion species of Mexico were assayed: C. noxius, C. suffusus, C. limpidus, C. elegans, C

  13. Evaluation of the Lethal Potency of Scorpion and Snake Venoms and Comparison between Intraperitoneal and Intravenous Injection Routes

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    Naoual Oukkache

    2014-06-01

    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

  14. Evolutionary diversification of Mesobuthus α-scorpion toxins affecting sodium channels.

    Science.gov (United States)

    Zhu, Shunyi; Peigneur, Steve; Gao, Bin; Lu, Xiuxiu; Cao, Chunyang; Tytgat, Jan

    2012-01-01

    α-Scorpion toxins constitute a family of peptide modulators that induce a prolongation of the action potential of excitable cells by inhibiting voltage-gated sodium channel inactivation. Although they all adopt a conserved structural scaffold, the potency and phylogentic preference of these toxins largely vary, which render them an intriguing model for studying evolutionary diversification among family members. Here, we report molecular characterization of a new multigene family of α-toxins comprising 13 members (named MeuNaTxα-1 to MeuNaTxα-13) from the scorpion Mesobuthus eupeus. Of them, five native toxins (MeuNaTxα-1 to -5) were purified to homogeneity from the venom and the solution structure of MeuNaTxα-5 was solved by nuclear magnetic resonance. A systematic functional evaluation of MeuNaTxα-1, -2, -4, and -5 was conducted by two-electrode voltage-clamp recordings on seven cloned mammalian voltage-gated sodium channels (Na(v)1.2 to Na(v)1.8) and the insect counterpart DmNa(v)1 expressed in Xenopus oocytes. Results show that all these four peptides slow inactivation of DmNa(v)1 and are inactive on Na(v)1.8 at micromolar concentrations. However, they exhibit differential specificity for the other six channel isoforms (Na(v)1.2 to Na(v)1.7), in which MeuNaTxα-4 shows no activity on these isoforms and thus represents the first Mesobuthus-derived insect-selective α-toxin identified so far with a half maximal effective concentration of 130 ± 2 nm on DmNa(v)1 and a half maximal lethal dose of about 200 pmol g(-1) on the insect Musca domestica; MeuNaTxα-2 only affects Na(v)1.4; MeuNaTxα-1 and MeuNaTxα-5 have a wider range of channel spectrum, the former active on Na(v)1.2, Na(v)1.3, Na(v)1.6, and Na(v)1.7, whereas the latter acting on Na(v)1.3-Na(v)1.7. Remarkably, MeuNaTxα-4 and MeuNaTxα-5 are two nearly identical peptides differing by only one point mutation at site 50 (A50V) but exhibit rather different channel subtype selectivity, highlighting a

  15. Effect of clonidine in mice injected with Tityus discrepans scorpion venom.

    Science.gov (United States)

    Rodríguez, A; Zerpa, H; Ruiz, A; Bermúdez, V; García, F; Silva, A; Gutiérrez, L; Villasmil, S

    2013-03-01

    A study was conducted to assess the effect of clonidine (α(2)-adrenoceptor selective agonist) on glycemia, serum and urine α-amylase, blood urea nitrogen (BUN), serum creatinine, white blood cell count, kidney histology and zymogen granule content in pancreatic acini, in mice under the effect of Tityus discrepans (Td) scorpion venom. BALB/c male mice (20 ± 2 g, n = 7-11) were intraperitoneally (ip) injected with a sublethal dose (1 μg/g) of Td venom, and were treated (ip) with 0.1 μg/g of clonidine (Catapresan(®)) or 0.9% NaCl 30 min after the venom injection, and then every 2 h. Six hours later, mice were anesthetized with diethylether and urine and blood samples were withdrawn by cystocentesis and cardiocentesis, respectively. Tissue samples were obtained and fixed immediately in buffered formalin (2%, pH 7.4) and then processed for stain H&E. Td venom did not cause hyperglycemia by itself. However, clonidine induced hyperglycemia, which was synergized by Td venom. Although the venom did not produce hyperamylasemia, clonidine significantly diminished serum α-amylase activity in envenomed mice. Td venom did not significantly increase urinary α-amylase activity, which was unaffected by clonidine. Morphometric analysis using microphotographs of pancreata from mice injected with Td venom showed a reduced zymogen granule content as judged by the acidophilic bidimensional area of acini. This effect was significantly reduced by clonidine. Kidney samples showed histological changes which were partially affected by the drug. Clonidine reduced the increase in BUN and serum creatinine concentration in envenomed mice. Td venom produced neutrophilia and lymphopenia, which were clonidine-resistant at the assayed dose. These results suggest that α(2)-adrenoceptor selective agonists would be able to reduce some scorpion venom-induced renal and pancreatic disturbances, possibly through the inhibition of neurotransmitter release from presynaptic cholinergic and

  16. Variation in quantity and composition of cuticular hydrocarbons in the scorpion Buthus occitanus (Buthidae) in response to acute exposure to desiccation stress.

    Science.gov (United States)

    Gefen, E; Talal, S; Brendzel, O; Dror, A; Fishman, A

    2015-04-01

    Scorpions exhibit some of the lowest recorded water loss rates among terrestrial arthropods. Evaporative water loss to the surrounding environment occurs mainly through the integument, and thus its resistance to water loss has paramount significance for the ability of scorpions to tolerate extremely dry habitats. Cuticular hydrocarbons (HCs) deposited on the outer epicuticle play an important role in determining cuticular waterproofing, and seasonal variation in both cuticular HC quantity and composition has been shown to correlate with water loss rates. Precursor incorporation rates into cuticle HCs have been observed to be extremely low in scorpions compared with insects. We therefore used adult male Buthus occitanus (Buthidae) in order to test HC profile plasticity during acute exposure to 14 d and 28 d of experimental desiccation. Cuticular HC profile of hydrated scorpions was similar to that reported for several other scorpion species, consisting of similar fractions of n-alkanes and branched alkanes, with no evidence for unsaturation. Most abundant of the n-alkanes were n-heptacosane (C27; 19±2% of total HCs), n-nonacosane (C29; 16±1%) and n-hentriacontane (C31; 11±1%). Exposure to desiccation stress resulted in a significant increase in the total amount of extracted HCs, and in the relative abundance of branched alkanes at the expense of n-alkanes. Together with an increase in HC chain lengths, these changes mimic previously-reported seasonal variation among freshly-collected specimens. This indicates that scorpions respond to water shortage by regulating the properties of their passive integumental barrier to water loss.

  17. Antibacterial activity and mechanism of a scorpion venom peptide derivative in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Luyang Cao

    Full Text Available BmKn2 is an antimicrobial peptide (AMP characterized from the venom of scorpion Mesobuthus martensii Karsch by our group. In this study, Kn2-7 was derived from BmKn2 to improve the antibacterial activity and decrease hemolytic activity. Kn2-7 showed increased inhibitory activity against both gram-positive bacteria and gram-negative bacteria. Moreover, Kn2-7 exhibited higher antibacterial activity against clinical antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA. In addition, the topical use of Kn2-7 effectively protected the skin of mice from infection in an S. aureus mouse skin infection model. Kn2-7 exerted its antibacterial activity via a bactericidal mechanism. Kn2-7 killed S. aureus and E. coli rapidly by binding to the lipoteichoic acid (LTA in the S. aureus cell wall and the lipopolysaccharides (LPS in the E. coli cell wall, respectively. Finally, the hemolytic activity of Kn2-7 was significantly decreased, compared to the wild-type peptide BmKn2. Taken together, the Kn2-7 peptide can be developed as a topical therapeutic agent for treating bacterial infections.

  18. Hp1404, a new antimicrobial peptide from the scorpion Heterometrus petersii.

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    Zhongjie Li

    Full Text Available Antimicrobial peptides have attracted much interest as a novel class of antibiotics against a variety of microbes including antibiotics resistant strains. In this study, a new cationic antimicrobial peptide Hp1404 was identified from the scorpion Heterometrus petersii, which is an amphipathic α-helical peptide and has a specific inhibitory activity against gram-positive bacteria including methicillin-resistant Staphylococcus aureus. Hp1404 can penetrate the membrane of S. aureus at low concentration, and disrupts the cellular membrane directly at super high concentration. S. aureus does not develop drug resistance after multiple treatments with Hp1404 at sub MIC concentration, which is possibly associated with the antibacterial mechanism of the peptide. In addition, Hp1404 has low toxicity to both mammalian cells (HC₅₀  =  226.6 µg/mL and CC₅₀ > 100 µg/mL and balb-c mice (Non-toxicity at 80 mg/Kg by intraperitoneal injection and LD₅₀  =  89.8 mg/Kg by intravenous injection. Interestingly, Hp1404 can improve the survival rate of the MRSA infected balb-c mice in the peritonitis model. Taken together, Hp1404 may have potential applications as an antibacterial agent.

  19. Preparing and Characterizing Chitosan Nanoparticles Containing Hemiscorpius lepturus Scorpion Venom as an Antigen Delivery System

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    Mohammadpour Dounighi, N.

    2012-11-01

    Full Text Available In recent years, chitosan nanoparticles have been studied widely for protein delivery. In this study, Hemiscorpius lepturus (HL venom was encapsulated in chitosan nanoparticles. The aim of the present work was to carry out a systematic study for preparing biocompatible and biodegradable nanoparticles for loading HL scorpion venom and to evaluate their potential as an antigen delivery system. In this study, HL venom loaded chitosan nanoparticles fabricated by ionic gelation of chitosan and tripolyphosphate and the factors which may be influenced in the preparation of nanoparticles were analyzed. Also, their physicochemical properties and in vitro release behavior were studied. The optimum encapsulation efficiency and capacity were observed when the chitosan concentration and HL venom were 2mg/ml and 500µg/ml, respectively. The HL venom loaded nanoparticles were in the size range of 130-160nm (polydispersity index values of 0.423 and exhibited the positive zeta potential. Transmission electron microscope imaging showed spherical and smooth surface of nanoparticles. The profiles of the release exhibited a burst releases about 50% in the first 4 hr and then slowed down at a constant rate. The obtained results suggested that the chitosan nanoparticles prepared in this work had the potential for antigen delivery.

  20. Phylogeographic Study of Whip Scorpions (Chelicerata: Arachnida: Thelyphonida) in Japan and Taiwan.

    Science.gov (United States)

    Karasawa, Shigenori; Nagata, Satomi; Aoki, Jun-ichi; Yahata, Kensuke; Honda, Masanao

    2015-08-01

    Whip scorpions (Thelyphonida), comprising an order in the class Arachnida, are distributed from tropical to temperate zones. Two species occur exclusively in Japan and Taiwan, but the border of their distributional ranges is ambiguous in the Central Ryukyus (Japan). We collected new specimens from the Central Ryukyus and revealed that the border of distribution of the two species lies between the Central and Southern Ryukyus, i.e., the Kerama Gap. Moreover, the estimated divergence time (15.8 Mya) of the two species, based on the mitochondrial COI gene, was older than the recently estimated time (1.55 Mya) of formation of the Kerama Gap. These results highlight the risks of a priori assumption solely on the basis of geological data for applying it as a calibration point to some terrestrial animals in this region. Typopeltis stimpsonii was genetically divided into four lineages, two of which turned out to be endemic to the Okinawa Islands. All specimens from the main island of Japan and Shikoku were in one lineage, which was also found in the Amami Islands and Hachijojima Island. This suggests that these specimens may have been dispersed by human activity. Typopeltis crucifer included five genetic lineages. Species collected from Ishigakijima and Iriomotejima Islands were genetically diversified not between the borders of these islands but within Ishigakijima Island. This study also suggests that phylogenetic diversity of the species in the Southern Ryukyus have increased through two times of invasions from Taiwan.

  1. Accelerated evolution and functional divergence of scorpion short-chain K+ channel toxins after speciation.

    Science.gov (United States)

    Gao, Bin; Zhu, Shunyi

    2012-10-01

    The α-KTx14 subfamily of scorpion toxins is a group of short-chain polypeptides affecting K(+) channels, including five known members which are restrictedly distributed in Mesobuthus martensii. Here, we describe seven new α-KTx14 peptides from M. martensii and its sibling species Mesobuthus eupeus, two of which (termed MarKTX-3 and MeuKTX-1) were chemically synthesized and refolded for structural and functional studies. Electrophysiological recordings of effects of these two peptides on an array of voltage-gated potassium channels revealed that MarKTX-3 was capable of inhibiting five mammalian K(v)1 isoforms (rK(v)1.1-rK(v)1.5) and the Drosophila Shaker channel with low potency whereas MeuKTX-1 lacks such activity. Circular dichroism spectroscopy analysis combined with homology modeling demonstrates that MarKTX-3 and MeuKTX-1 both adopt a similar cysteine-stabilized α-helical and β-sheet fold. Evolutionary analysis indicates accelerated amino acid substitutions in the mature-peptide-encoding regions of orthologous α-KTx14 peptides after speciation, thereby providing evidences for adaptive evolution and functional divergence of this subfamily.

  2. Insects as biological models to assay spider and scorpion venom toxicity

    Directory of Open Access Journals (Sweden)

    M. F. Manzoli-Palma

    2003-01-01

    Full Text Available This study was undertaken to develop an experimental protocol using insects as biological models to assay venom toxicity of the following spiders Loxosceles gaucho, Phoneutria nigriventer, Nephilengys cruentata and Tityus serrulatus scorpion. Three different insect species were bioassayed: Apis mellifera (Hymenoptera, Grillus assimilis (Orthoptera, and Diatraea saccharalis (Lepidoptera. Venoms were injected into the hemocele of insects with a microsyringe at concentrations that caused dose/weight-dependent effects; doses causing either paralysis (ED50 or death (LD50 were recorded for each venom and insect test-species. T. serrulatus and L. gaucho venoms were lethal to all tested species, while P. nigriventer venom caused paralysis and death, and N. cruentata venom caused only paralysis at the doses assayed. A comparison between the insect test species described above revealed that A. mellifera was highly sensitive to all venoms tested; even a tiny amount of N. cruentata non-lethal venom caused a change in the walking pattern leading to transient paralysis. D. saccharalis larvae were very resistant to all four venoms.

  3. PIXE-STIM microtomography: Zinc and manganese concentrations in a scorpion stinger

    Science.gov (United States)

    Schofield, Robert M. S.; Lefevre, Harlan W.

    1992-10-01

    Microtomography using PIXE (proton induced X-ray emission) is developed and applied. Iterative algorithms for emission tomography (Donner algorithms) are modified for this purpose. STIM (scanning transmission ion microscopy) microtomography provides the required local X-ray attenuation factors and X-ray production cross sections (σ x's). The variation in σ x is treated along with X-ray attenuation in an effective attenuation factor. Several criteria for the optimal number of iterations are discussed. Element density values obtained from PIXE tomography are normalized with density values from STIM tomography to provide local concentration values. Three transverse sections of the sting of a scorpion, Hadrurus arizonensis, are reconstructed tomographically. Local zinc concentrations reaching as high as 25(± 3)% of dry mass are found. Manganese concentrations reaching 3.8(± 0.5)% of dry mass are also found. In the section manifesting high concentrations of both manganese and zinc, the zinc is found mainly in a band beneath the manganese-rich surface layer. Specimen damage during PIXE is found not to have significantly affected the results.

  4. Structural Similarity between Defense Peptide from Wheat and Scorpion Neurotoxin Permits Rational Functional Design*

    Science.gov (United States)

    Berkut, Antonina A.; Usmanova, Dinara R.; Peigneur, Steve; Oparin, Peter B.; Mineev, Konstantin S.; Odintsova, Tatyana I.; Tytgat, Jan; Arseniev, Alexander S.; Grishin, Eugene V.; Vassilevski, Alexander A.

    2014-01-01

    In this study, we present the spatial structure of the wheat antimicrobial peptide (AMP) Tk-AMP-X2 studied using NMR spectroscopy. This peptide was found to adopt a disulfide-stabilized α-helical hairpin fold and therefore belongs to the α-hairpinin family of plant defense peptides. Based on Tk-AMP-X2 structural similarity to cone snail and scorpion potassium channel blockers, a mutant molecule, Tk-hefu, was engineered by incorporating the functionally important residues from κ-hefutoxin 1 onto the Tk-AMP-X2 scaffold. The designed peptide contained the so-called essential dyad of amino acid residues significant for channel-blocking activity. Electrophysiological studies showed that although the parent peptide Tk-AMP-X2 did not present any activity against potassium channels, Tk-hefu blocked Kv1.3 channels with similar potency (IC50 ∼ 35 μm) to κ-hefutoxin 1 (IC50 ∼ 40 μm). We conclude that α-hairpinins are attractive in their simplicity as structural templates, which may be used for functional engineering and drug design. PMID:24671422

  5. Structural similarity between defense peptide from wheat and scorpion neurotoxin permits rational functional design.

    Science.gov (United States)

    Berkut, Antonina A; Usmanova, Dinara R; Peigneur, Steve; Oparin, Peter B; Mineev, Konstantin S; Odintsova, Tatyana I; Tytgat, Jan; Arseniev, Alexander S; Grishin, Eugene V; Vassilevski, Alexander A

    2014-05-16

    In this study, we present the spatial structure of the wheat antimicrobial peptide (AMP) Tk-AMP-X2 studied using NMR spectroscopy. This peptide was found to adopt a disulfide-stabilized α-helical hairpin fold and therefore belongs to the α-hairpinin family of plant defense peptides. Based on Tk-AMP-X2 structural similarity to cone snail and scorpion potassium channel blockers, a mutant molecule, Tk-hefu, was engineered by incorporating the functionally important residues from κ-hefutoxin 1 onto the Tk-AMP-X2 scaffold. The designed peptide contained the so-called essential dyad of amino acid residues significant for channel-blocking activity. Electrophysiological studies showed that although the parent peptide Tk-AMP-X2 did not present any activity against potassium channels, Tk-hefu blocked Kv1.3 channels with similar potency (IC50 ∼ 35 μm) to κ-hefutoxin 1 (IC50 ∼ 40 μm). We conclude that α-hairpinins are attractive in their simplicity as structural templates, which may be used for functional engineering and drug design. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Fluorescent protein-scorpion toxin chimera is a convenient molecular tool for studies of potassium channels.

    Science.gov (United States)

    Kuzmenkov, Alexey I; Nekrasova, Oksana V; Kudryashova, Kseniya S; Peigneur, Steve; Tytgat, Jan; Stepanov, Alexey V; Kirpichnikov, Mikhail P; Grishin, Eugene V; Feofanov, Alexey V; Vassilevski, Alexander A

    2016-09-21

    Ion channels play a central role in a host of physiological and pathological processes and are the second largest target for existing drugs. There is an increasing need for reliable tools to detect and visualize particular ion channels, but existing solutions suffer from a number of limitations such as high price, poor specificity, and complicated protocols. As an alternative, we produced recombinant chimeric constructs (FP-Tx) consisting of fluorescent proteins (FP) fused with potassium channel toxins from scorpion venom (Tx). In particular, we used two FP, eGFP and TagRFP, and two Tx, OSK1 and AgTx2, to create eGFP-OSK1 and RFP-AgTx2. We show that these chimeras largely retain the high affinity of natural toxins and display selectivity to particular ion channel subtypes. FP-Tx are displaced by other potassium channel blockers and can be used as an imaging tool in ion channel ligand screening setups. We believe FP-Tx chimeras represent a new efficient molecular tool for neurobiology.

  7. Straightforward approach to produce recombinant scorpion toxins-Pore blockers of potassium channels.

    Science.gov (United States)

    Nekrasova, Oksana; Kudryashova, Ksenia; Fradkov, Arkadiy; Yakimov, Sergey; Savelieva, Maria; Kirpichnikov, Mikhail; Feofanov, Alexey

    2017-01-10

    Scorpion venom peptide blockers (KTx) of potassium channels are a valuable tool for structure-functional studies and prospective candidates for medical applications. Low yields of recombinant KTx hamper their wide application. We developed convenient and efficient bioengineering approach to a large-scale KTx production that meets increasing demands for such peptides. Maltose-binding protein was used as a carrier for cytoplasmic expression of folded disulfide-rich KTx in E. coli. TEV protease was applied for in vitro cleavage of the target peptide from the carrier. To produce KTx with retained native N-terminal sequence, the last residue of TEV protease cleavage site (CSTEV) was occupied by the native N-terminal residue of a target peptide. It was shown that decreased efficiency of hydrolysis of fusion proteins with non-canonical CSTEV can be overcome without by-product formation. Disulfide formation and folding of a target peptide occurred in cytoplasm eliminating the need for renaturation procedure in vitro. Advantages of this approach were demonstrated by producing six peptides with three disulfide bonds related to four KTx sub-families and achieving peptide yields of 12-22mg per liter of culture. The developed approach can be of general use for low-cost production of various KTx, as well as other disulfide-rich peptides and proteins.

  8. Characterization of six toxins from the venom of the Moroccan scorpion Buthus occitanus mardochei.

    Science.gov (United States)

    Vargas, O; Martin, M F; Rochat, H

    1987-02-02

    When the venom of the Moroccan scorpion Buthus occitanus mardochei was submitted to a combination of several chromatographic steps (including gel-filtration and ion-exchange chromatographies), seven proteins were obtained, six being lethal to mice. These proteins have been characterized by their chemical, immunological and toxic properties. The amino acid sequence (66 residues) of Bom III, the most noteworthy toxin of the venom as for its amino acid composition, is proposed following automatic sequencing of the reduced and S-methylated protein and of chymotryptic peptides. It was obvious that this sequence is somewhat different from those of toxins belonging to the same structural and immunological group (Bom III was found to be immunologically related to Buthus occitanus tunetanus toxins I and II which both share with it 56% of homology. Furthermore, Bom III was found to be unable to compete (as does Bot I) with toxin II of Androctonus australis Hector (an alpha-type toxin) for neurotoxin binding site 3 on the sodium channel of rat brain synaptosomes. Bom III was also unable to compete with toxin II of Centruroides suffusus suffusus (a beta-type toxin) to neurotoxin binding site 4 of the same channel.

  9. Conformational flexibility of a scorpion toxin active on mammals and insects: a circular dichroism study.

    Science.gov (United States)

    Loret, E P; Sampieri, F; Roussel, A; Granier, C; Rochat, H

    1990-01-01

    Three scorpion toxins have been analyzed by circular dichroism in water and in 2,2,2-trifluoroethanol (TFE) solutions. These toxins were chosen because they are representative of three kinds of pharmacological activities: (1) toxin AaH IT2, an antiinsect toxin purified from the venom of Androctonus australis Hector, which is able to bind to insect nervous system preparation, (2) toxin Css II, from the venom of Centruroides suffusus suffusus, which is a beta-type antimammal toxin capable of binding to mammal nervous system preparation, and (3) the toxin Ts VII from the venom of Tityus serrulatus, which is able to bind to both types of nervous systems. In order to minimize bias, CD data were analyzed by a predictive algorithm to assess secondary structure content. Among the three molecules, Ts VII presented the most unordered secondary structure in water, but it gained in ordered forms when solubilized in TFE. These results indicated that the Ts VII backbone is the most flexible, which might result in a more pronounced tendency for this toxin molecule to undergo conformational changes. This is consistent with the fact that it competes with both antiinsect and beta-type antimammal toxins for the binding to the sodium channel.

  10. Serological, biochemical and enzymatic alterations in rodents after experimental envenomation with Hadruroides lunatus scorpion venom.

    Science.gov (United States)

    Costal-Oliveira, F; Guerra-Duarte, C; Castro, K L P; Tintaya, B; Bonilla, C; Silva, W; Yarlequé, A; Fujiwara, R; Melo, M M; Chávez-Olórtegui, C

    2015-09-01

    Toxic effects of Peruvian Hadruroides lunatus scorpion venom on different biochemical and enzymatic parameters in blood serum of Wistar rats and Swiss mice were determined after experimental envenomation. An increase in enzymatic activities of Aspartate Aminotransferase (AST), Lactate Dehydrogenase (LDH) and levels of serum protein and albumin were observed while a decrease in creatinine level in serum was perceived after 30 min of envenomation. No alterations in urea levels and in kidney histology were detected in the envenomed rats. The global leukocytes count was diminished, with decrease in lymphocytes, eosinophils and neutrophils levels in the bloodstream, while no alterations were found in hematological parameters of red series in rats injected with H. lunatus venom. IL-2, IL-4, IL-6, INF-γ, TNF, IL-17A and IL-10 levels were evaluated 0.5, 3 and 6 h after experimental envenomation of mice with H. lunatus venom. From all the analyzed cytokines, only IL-6 showed an increase in serum levels. Taken together, these results point out that envenomation by H. lunatus can impair hematological and immunological parameters and therefore might be monitored in accidents involving this species.

  11. Venom from Cuban Blue Scorpion has tumor activating effect in hepatocellular carcinoma

    Science.gov (United States)

    Giovannini, Catia; Baglioni, Michele; Baron Toaldo, Marco; Cescon, Matteo; Bolondi, Luigi; Gramantieri, Laura

    2017-01-01

    Complementary and alternative medicine (CAM) is the term used to describe many kinds of products, practices, and systems that are not part of conventional medicine. Cancer patients usually do everything they can to combat the disease, manage its symptoms, and cope with the side effects of treatment. Unfortunately, patients who use CAM underestimate the risk of interaction with cancer therapy or worse they omit conventional therapy thus reducing the possibility of cancer remission. Herein we analyzed the effects of Vidatox 30 CH (venom extracted from the Junceus Rhopalurus scorpion) on hepatocellular carcinoma (HCC), the second leading cause of cancer-related deaths. We found out that Vidatox increases HCC proliferation and invasion whereas it does not seem to interact with sorafenib, the orally active multikinase inhibitor approved for the treatment of advanced hepatocellular carcinoma. Our results suggest that the concentration of Vidatox used in the present study has not anti-neoplastic effects and care must be taken in hiring Vidatox in patients with HCC. PMID:28322221

  12. Recombinant scorpion insectotoxin AaIT kills specifically insect cells but not human cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LCs0 value of 18.4 uM and 0.70 μM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 μM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3μM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells.

  13. Data mining using multivariate The circadian rhythm and visual elements in scorpions: A review

    Directory of Open Access Journals (Sweden)

    M. R. Warburg

    2013-12-01

    Full Text Available The purpose of this paper is to review the state of research in this field and to outline future ways how to proceed. The term: "Zeitgeber", implies 'time giver' meaning: synchronizer when an external entrainment factor synchronizes the endogenous rhythm. Is this 'time giver', the chronological date in the sense that it is related to the time of day as reflected in the natural light-dark cycles? Or does it mean cyclic phases of activity as demonstrated in the laboratory? Moreover, is it totally independent of the animal's physiological condition? This subject was studied largely in buthid species (15 of a total of only 30 scorpion species. Moreover, many (over 25% of the studies (19 were done on a single buthid species: Androctonus australis. Species diversity was observed only by one author's work who studied eye structure in seven species. Since he found variability in eye structure it would not be advisable to generalize. The fact that experimenting was carried out irrespective of species diversity, gender, ecological or physiological conditions, and was usually done on animals kept in captivity for some time before the experimenting had started, is a major drawback to this kind of study. The diurnal rhythms is triggered either directly through spontaneous arrhythmic activity in the central nervous system, or by neurosecretory material. It is possible that these differences arise from either different technical treatments or due to basic problems, and these need to be clarified.

  14. Expression and characterization of a novel scorpine-like peptide Ev37, from the scorpion Euscorpiops validus.

    Science.gov (United States)

    Feng, Jing; Yu, Congya; Wang, Mingyu; Li, Zhi; Wu, Yingliang; Cao, Zhijian; Li, Wenxin; He, Xiaohua; Han, Song

    2013-03-01

    Scorpion venom contains a group of two-domain peptides that function to block potassium channels or have cytolytic activities. These peptides, whose functions are poorly studied, are named β-KTx or scorpine-like peptides. Ev37, the first identified gene in the Euscorpiidae family, which encoded a novel scorpine-like peptide, was cloned from the venom cDNA library of scorpion Euscorpiops validus. Sequence analysis showed that the mature Ev37 peptide contained 78 amino acid residues, which formed two structural domains: a putative α-helical N-terminus and a C-terminus with the cysteine-stabilized α/β motif. The peptide rEv37 and two truncated peptides representing the individual structural domains (Ev37-N and Ev37-C) were expressed in Escherichia coli and purified for functional study. Unlike classic scorpine-like peptides, rEv37 and truncated peptides showed no cytolytic activity against bacteria or eukaryotic cells. Interestingly, rEv37 selectively inhibited Kv1.3 channel without effectively blocking Kv1.1 and Kv1.2 channels. Neither Ev37-N nor Ev37-C blocked Kv1.3 channel, suggesting that both the N-terminal and C-terminal domain of Ev37 are likely involved in the interaction with Kv1.3 channel. These results not only enrich our knowledge of scorpion toxins from scorpine-like subfamily but also provide a novel template with unique structure for designing new types of selective Kv1.3 blockers.

  15. Variability of Potassium Channel Blockers in Mesobuthus eupeus Scorpion Venom with Focus on Kv1.1

    Science.gov (United States)

    Kuzmenkov, Alexey I.; Vassilevski, Alexander A.; Kudryashova, Kseniya S.; Nekrasova, Oksana V.; Peigneur, Steve; Tytgat, Jan; Feofanov, Alexey V.; Kirpichnikov, Mikhail P.; Grishin, Eugene V.

    2015-01-01

    The lesser Asian scorpion Mesobuthus eupeus (Buthidae) is one of the most widely spread and dispersed species of the Mesobuthus genus, and its venom is actively studied. Nevertheless, a considerable amount of active compounds is still under-investigated due to the high complexity of this venom. Here, we report a comprehensive analysis of putative potassium channel toxins (KTxs) from the cDNA library of M. eupeus venom glands, and we compare the deduced KTx structures with peptides purified from the venom. For the transcriptome analysis, we used conventional tools as well as a search for structural motifs characteristic of scorpion venom components in the form of regular expressions. We found 59 candidate KTxs distributed in 30 subfamilies and presenting the cysteine-stabilized α/β and inhibitor cystine knot types of fold. M. eupeus venom was then separated to individual components by multistage chromatography. A facile fluorescent system based on the expression of the KcsA-Kv1.1 hybrid channels in Escherichia coli and utilization of a labeled scorpion toxin was elaborated and applied to follow Kv1.1 pore binding activity during venom separation. As a result, eight high affinity Kv1.1 channel blockers were identified, including five novel peptides, which extend the panel of potential pharmacologically important Kv1 ligands. Activity of the new peptides against rat Kv1.1 channel was confirmed (IC50 in the range of 1–780 nm) by the two-electrode voltage clamp technique using a standard Xenopus oocyte system. Our integrated approach is of general utility and efficiency to mine natural venoms for KTxs. PMID:25792741

  16. Hot and not-so-hot females: reproductive state and thermal preferences of female Arizona Bark Scorpions (Centruroides sculpturatus).

    Science.gov (United States)

    Webber, M M; Gibbs, A G; Rodríguez-Robles, J A

    2015-02-01

    For ectotherms, environmental temperatures influence numerous life history characteristics, and the body temperatures (Tb ) selected by individuals can affect offspring fitness and parental survival. Reproductive trade-offs may therefore ensue for gravid females, because temperatures conducive to embryonic development may compromise females' body condition. We tested whether reproduction influenced thermoregulation in female Arizona Bark Scorpions (Centruroides sculpturatus). We predicted that gravid females select higher Tb and thermoregulate more precisely than nonreproductive females. Gravid C. sculpturatus gain body mass throughout gestation, which exposes larger portions of their pleural membrane, possibly increasing their rates of transcuticular water loss in arid environments. Accordingly, we tested whether gravid C. sculpturatus lose water faster than nonreproductive females. We determined the preferred Tb of female scorpions in a thermal gradient and measured water loss rates using flow-through respirometry. Gravid females preferred significantly higher Tb than nonreproductive females, suggesting that gravid C. sculpturatus alter their thermoregulatory behaviour to promote offspring fitness. However, all scorpions thermoregulated with equal precision, perhaps because arid conditions create selective pressure on all females to thermoregulate effectively. Gravid females lost water faster than nonreproductive animals, indicating that greater exposure of the pleural membrane during gestation enhances the desiccation risk of reproductive females. Our findings suggest that gravid C. sculpturatus experience a trade-off, whereby selection of higher Tb and increased mass during gestation increase females' susceptibility to water loss, and thus their mortality risk. Elucidating the mechanisms that influence thermal preferences may reveal how reproductive trade-offs shape the life history of ectotherms in arid environments.

  17. Ecophysiological adaptations to dry thermal environments measured in two unrestrained Namibian scorpions, Parabuthus villosus (Buthidae) and Opisthophthalmus flavescens (Scorpionidae).

    Science.gov (United States)

    Bridges, C R; le Roux, J M; van Aardt, W J

    1997-01-01

    The daily changes in body temperature experienced by Parabuthus villosus (Buthidae), a scorpion found on the gravel plains around Gobabeb, Namibia, and by Opisthophthalmus flavescens (Scorpionidae), a dune-dwelling species from the same area, were measured under similar field conditions. Thermocouples implanted under the segments of the mesosoma measured maximum temperatures as high as 43 degrees C in the shade. Air temperatures reached a maximum of 33 degrees C during the daytime and a minimum of 12 degrees C at night. Very low metabolic rates compared with those of other nonsedentary invertebrates were recorded in both species; oxygen consumption ranged from 8 microL g-1 h-1 at 16 degrees C to 115 microL g-1 h-1 at 40 degrees C. A pulsed Doppler system was used to measure heart rate in situ in free-moving scorpions. At night, heart rate declined to about 4 beats min-1 in resting undisturbed scorpions. During daylight excursions and while scorpions hunted for food, heart rates as high as 180 beats min-1 were observed. Heart rate was linearly correlated with temperature in P. villosus, with a slope of 2.37 (Q10 = 2.18), but in O. flavescens only a limited correlation was observed, with a slope of 1.18 (Q10 = 1.69). In O. flavescens, heart rate showed hysteresis as body temperature rose during daylight and then decreased during the late afternoon and evening; the reverse was observed in P. villosus. In both species, haemocyanin-oxygen affinity was independent of temperature, with a higher oxygen affinity and a larger pH sensitivity in O. flavescens. The Q10's of oxygen consumption and heart rate are quite different in O. flavescens but not as different in P. villosus. Although changes in the cardiovascular system, such as stroke volume, may also play a role in meeting increased oxygen demand, the features of the haemocyanin oxygen transport system, such as the absence of temperature sensitivity and a marked pH sensitivity, can also influence the maintenance of VO2

  18. Modeling of spatial distribution for scorpions of medical importance in the São Paulo State, Brazil.

    Science.gov (United States)

    Brites-Neto, José; Duarte, Keila Maria Roncato

    2015-07-01

    In this work, we aimed to develop maps of modeling geographic distribution correlating to environmental suitability for the two species of scorpions of medical importance at São Paulo State and to develop spatial configuration parameters for epidemiological surveillance of these species of venomous animals. In this study, 54 georeferenced points for Tityus serrulatus and 86 points for Tityus bahiensis and eight environmental indicators, were used to generate species distribution models in Maxent (maximum entropy modeling of species geographic distributions) version 3.3.3k using 70% of data for training (n=38 to T. serrulatus and n=60 to T. bahiensis) and 30% to test the models (n=16 for T. serrulatus and n=26 for T. bahiensis). The logistic threshold used to cut models in converting the continuous probability model into a binary model was the "maximum test sensitivity plus specificity," provided by Maxent, with results of 0.4143 to T. serrulatus and of 0.3401 to T. bahiensis. The models were evaluated by the area under the curve (AUC), using the omission error and the binomial probability. With the data generated by Maxent, distribution maps were produced using the "ESRI(®) ArcGIS 10.2.2 for Desktop" software. The models had high predictive success (AUC=0.7698±0.0533, omission error=0.2467 and p<0.001 for T. serrulatus and AUC=0.8205±0.0390, omission error=0.1917 and p<0.001 for T. bahiensis) and the resultant maps showed a high environmental suitability in the north, central, and southeast of the state, confirming the increasing spread of these species. The environmental variables that mostly contributed to the scorpions species distribution model were rain precipitation (28.9%) and tree cover (28.2%) for the T. serrulatus and temperature (45.8%) and thermal amplitude (12.6%) for the T. bahiensis. The distribution model of these species of medical importance scorpions in São Paulo State revealed a higher environmental suitability of these species in the

  19. Modeling of spatial distribution for scorpions of medical importance in the São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    José Brites-Neto

    2015-07-01

    Full Text Available Aim: In this work, we aimed to develop maps of modeling geographic distribution correlating to environmental suitability for the two species of scorpions of medical importance at São Paulo State and to develop spatial configuration parameters for epidemiological surveillance of these species of venomous animals. Materials and Methods: In this study, 54 georeferenced points for Tityus serrulatus and 86 points for Tityus bahiensis and eight environmental indicators, were used to generate species distribution models in Maxent (maximum entropy modeling of species geographic distributions version 3.3.3k using 70% of data for training (n=38 to T. serrulatus and n=60 to T. bahiensis and 30% to test the models (n=16 for T. serrulatus and n=26 for T. bahiensis. The logistic threshold used to cut models in converting the continuous probability model into a binary model was the “maximum test sensitivity plus specificity,” provided by Maxent, with results of 0.4143 to T. serrulatus and of 0.3401 to T. bahiensis. The models were evaluated by the area under the curve (AUC, using the omission error and the binomial probability. With the data generated by Maxent, distribution maps were produced using the “ESRI® ArcGIS 10.2.2 for Desktop” software. Results: The models had high predictive success (AUC=0.7698±0.0533, omission error=0.2467 and p<0.001 for T. serrulatus and AUC=0.8205±0.0390, omission error=0.1917 and p<0.001 for T. bahiensis and the resultant maps showed a high environmental suitability in the north, central, and southeast of the state, confirming the increasing spread of these species. The environmental variables that mostly contributed to the scorpions species distribution model were rain precipitation (28.9% and tree cover (28.2% for the T. serrulatus and temperature (45.8% and thermal amplitude (12.6% for the T. bahiensis. Conclusion: The distribution model of these species of medical importance scorpions in São Paulo State

  20. Modulation of the Pharmacological and Biochemical Actions of Leiurusquinquestriatus (L.q) Scorpion Venom by Exposure to Gamma Radiation

    OpenAIRE

    Heba A. Mohamed*, Esmat A. Shaaban* , Aber M Amin** and Sanaa A. Kenawy

    2011-01-01

    This study was undertaken to evaluate the effect of gamma radiation (1.5 KGy & 3 KGy) on L.q scorpion venom. This was carried out by studying the toxicological, biochemical & immunological properties of the venom before and after exposure to gamma radiation. Material and methods Animals, venom, antivenin, gamma radiation, 125I. Results Data revealed that the toxicity of irradiated venom (1.5 KGy & 3 KGy) decreased as compared to that of the native one. LD50 of irradiated venom were 3.5 mg/kg ...

  1. Polyamide-scorpion cyclam lexitropsins selectively bind AT-rich DNA independently of the nature of the coordinated metal.

    Directory of Open Access Journals (Sweden)

    Anthony T S Lo

    Full Text Available Cyclam was attached to 1-, 2- and 3-pyrrole lexitropsins for the first time through a synthetically facile copper-catalyzed "click" reaction. The corresponding copper and zinc complexes were synthesized and characterized. The ligand and its complexes bound AT-rich DNA selectively over GC-rich DNA, and the thermodynamic profile of the binding was evaluated by isothermal titration calorimetry. The metal, encapsulated in a scorpion azamacrocyclic complex, did not affect the binding, which was dominated by the organic tail.

  2. Alacranes (Arachnida: Scorpiones de Frontera Corozal, en la selva lacandona, Chiapas, México, con la descripción de una nueva especie de Diplocentrus (Diplocentridae Scorpions (Arachnida, Scorpiones from Frontera Corozal, in the Lacandona rainforest, Chiapas, México, with the description of a new species of Diplocentrus (Diplocentridae

    Directory of Open Access Journals (Sweden)

    Oscar F. Francke B.

    2007-06-01

    Full Text Available Se realizaron recolectas diurnas y nocturnas en la Comunidad de Frontera Corozal, Municipio de Ocosingo, Chiapas, México. Se registran 3 especies de escorpiones, 2 de la familia Buthidae y una de la familia Diplocentridae. Centruroides schmidti Sissom es un nuevo registro para el estado de Chiapas y Diplocentrus chol es una especie nueva.Diurnal and nocturnal collecting in the community of Frontera Corozal, Municipio Ocosingo, Chiapas, Mexico, revealed three species of scorpions, two belonging to the family Buthidae and one to Diplocentridae. Centruroides schmidtiSissom is a new record for the state of Chiapas, and Diplocentrus chol is described as a new species.

  3. Cloning and characterization of a novel calcium channel toxin-like gene BmCa1 from Chinese scorpion Mesobuthus martensii Karsch.

    Science.gov (United States)

    Zhijian, Cao; Yun, Xie; Chao, Dai; Shunyi, Zhu; Shijin, Yin; Yingliang, Wu; Wenxin, Li

    2006-06-01

    Many studies have been carried on peptides and genes encoding scorpion toxins from the venom of Mesobuthus martensii Karsch (synonym: Buthus martensii Karsch, BmK), such as Na+, K+ and Cl- channel modulators. In this study, a novel calcium channel toxin-like gene BmCa1 was isolated and characterized from the venom of Mesobuthus martensii Karsch. First, a partial cDNA sequence of the Ca2+ channel toxin-like gene was identified by random sequencing method from a venomous gland cDNA library of Mesobuthus martensii Karsch. The full-length sequence of BmCa1 was then obtained by 5'RACE technique. The peptide deduced from BmCa1 precursor nucleotide sequence contains a 27-residue signal peptide and a 37-residue mature peptide. Although BmCa1 and other scorpion toxins are different at the gene and protein primary structure levels, BmCa1 has the same precursor nucleotide organization and cysteine arrangement as that of the first subfamily members of calcium channel scorpion toxins. Genomic DNA sequence of BmCa1 was also cloned by PCR. Sequence analysis showed that BmCa1 gene consists of three exons separated by two introns of 72 bp and 1076 bp in length, respectively. BmCa1 is the first calcium channel toxin-like gene cloned from the venom of Mesobuthus martensii Karsch and potentially represents a novel class of calcium channel toxins in scorpion venoms.

  4. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod

    NARCIS (Netherlands)

    Fuzita, F.J.; Pinkse, M.W.H.; Patane, J.S.L.; Juliano, M.A.; Verhaert, P.D.E.M.; Lopes, A.R.

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health

  5. Biochemical, Transcriptomic and Proteomic Analyses of Digestion in the Scorpion Tityus serrulatus: Insights into Function and Evolution of Digestion in an Ancient Arthropod

    NARCIS (Netherlands)

    Fuzita, F.J.; Pinkse, M.W.H.; Patane, J.S.L.; Juliano, M.A.; Verhaert, P.D.E.M.; Lopes, A.R.

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health

  6. Purification, Characterization and 1H NMR Resonance Assignment of an α-Like Neurotoxin BmK 16 from the Venom of Chinese Scorpion Buthus martensii Karsch

    Institute of Scientific and Technical Information of China (English)

    ZHANG, Nai-Xia; WU, Gong; WANG, Zhong-Hua; WU, Hou-Ming

    2003-01-01

    A natural scorpion toxin BmK 16 was purified for the first time from the venom of the Chinese scorpion Buthus martensii Karsch (BmK) by using combined gel-filtration, ion exchange and reversed phase chromatography. The sequence of the Nterminal 8 amino acid residues was determined by Edman degradation. Using the N-terminal sequence as a tag, the database searching revealed a hit in the scorpion cDNA Bank.The sequence for N-terminal 8 amino acid residues, molecular weight and amino acid compositions of BmK 16 were identical with the calculated values according to the first 64 residues' sequence of the precursor peptide alpha-neurotoxin TX16 derived from the sequence of the cDNA AF156597 (EMBL). The sequence-specific resonance assignment of BmK 16 was achieved and the intact sequence of BmK 16 was determined as followings: VRDAY IAKPH NCVYE CARNE YCNDL CTKNGAKSGY CQWVG KYGNG CWCKE LPDNV PIRVP GKCH.Furthermore, the results from the sequence homology analysis and the toxicity assays indicated that BmK 16 was an -like scorpion neurotoxin.

  7. Biochemical, Transcriptomic and Proteomic Analyses of Digestion in the Scorpion Tityus serrulatus: Insights into Function and Evolution of Digestion in an Ancient Arthropod

    NARCIS (Netherlands)

    Fuzita, F.J.; Pinkse, M.W.H.; Patane, J.S.L.; Juliano, M.A.; Verhaert, P.D.E.M.; Lopes, A.R.

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challe

  8. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod

    NARCIS (Netherlands)

    Fuzita, F.J.; Pinkse, M.W.H.; Patane, J.S.L.; Juliano, M.A.; Verhaert, P.D.E.M.; Lopes, A.R.

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challe

  9. Cardiopulmonary complications induced by Iranian Mesobuthus eupeus scorpion venom in anesthetized rabbits

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    E Zayerzadeh

    2010-01-01

    Full Text Available Scorpion envenomation is a life-threatening condition, especially in children and elderly individuals affected by respiratory and cardiovascular diseases. In this study, the toxic effects of median lethal dose (LD50 injections of Mesobuthus eupeus (Me venom on the heart and lungs of anesthetized rabbits were investigated. Six rabbits were selected and alterations in their electrocardiogram, heart rate, respiration and blood pressure before and after venom injection were recorded. Cardiac troponin T (cTnT, creatinine kinase muscle-brain fraction (CK-MB and lactate dehydrogenase (LDH were measured at 0, 1 and 3 hours after envenomation and pathology studies were carried out postmortem. All the animals showed signs and symptoms of envenomation within 40 minutes and died 3 to 3.5 hours after venom injection. Pathology studies revealed alveolar edema in 100% of the rabbits and myocardial infarction in 16%. The main histopathological changes were myocytolysis, coagulation necrosis, focal hemorrhage, thrombus formation both in myocardium and on endocardial surfaces as well as inflammatory infiltrates in the heart and hemorrhage, vascular thrombus and interstitial inflammation in the lungs. ECG monitoring of rabbits showed ST elevation, ST depression and inverted T and Q waves. In addition, although cTnT levels increased in 16% of the animals and serum LDH was also augmented, none of these changes was statistically significant. The enzyme CK-MB also did not show any change after Me venom injection. In conclusion, the results of this study showed that Me venom killed animals in less than 3.5 hours through severe pulmonary damage and it appears that the deaths could not be attributed to cardiovascular lesions. Therefore, Me venom effects on the lungs are so important that they appear to be independent of heart damage.

  10. Scorpion toxins modify phytopathogenic fungus physiology. A possible source of new fungicides.

    Science.gov (United States)

    Joya, Galax; D'Suze, Gina; Salazar, Víctor; Rosales, Arnaldo; Sevcik, Carlos; Visbal, Gonzalo; Ferreira, André T S; Perales, Jonas

    2011-06-08

    Seven toxins (F1-F7) were purified from Tityus discrepans scorpion venom on a C18 HPLC column. The compounds were fungitoxic on Macrophomina phaseolina. The molecular masses of F1-F7 were (Da) 1061.1, 7328.8, 7288.3, 7268.5, 7104.6, 6924.6, and 6823.3, respectively. It is not known if F1 is a small peptide or some other kind of organic molecule. Compounds F2-F7 were peptides. The most potent was F7, with a minimal inhibition concentration of 0.4 μg/μL and a concentration for 50% inhibition of 0.13 μg/μL. Fungal esterase activity was abolished by F2, F3, and F5 and inhibited by 89, 60, 58, and 54% by F4, F6, F7, and F1, respectively. F1, F2, F5, and F7 induced an increase on hyphae chitin wall and septum thickness. Peptides F3-F6 induced efflux of the fluorescent dye Na-CoroNa Red complex from hyphae. Only F5 and F6 were inhibited by the prokaryote sodium channel blockers amiloride and mibefradil. Gas chromatography-mass spectrometry analysis suggested that F1, F5, F6, and F7 altered sterol biosynthesis either by inhibiting ergosterol biosynthesis or by producing ergosterol analogues. The peptides affect M. phaseolina viability by three mechanisms: decreasing esterase activity, altering Na(+) membrane permeability, and altering wall sterol biosynthesis. It seems that interfering with sterol synthesis is an important mechanism behind the effect of the fungicideal toxins. However, the antifungal effects at short times are indicative of a direct esterase inhibition, which, with the increased membrane leakiness to Na(+), makes the fungus inviable.

  11. Exploiting cross-reactivity to neutralize two different scorpion venoms with one single chain antibody fragment.

    Science.gov (United States)

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D; Becerril, Baltazar

    2011-02-25

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Becerril, B. (2005) FEBS J. 272, 2591-2601) and Css2 (this work). Each evolved variant showed strong cross-reactivity against several toxins, and was capable of neutralizing Cn2 and Css2. Furthermore, each variant neutralized the whole venoms of the above species. As far as we know, this is the first report of antibodies with such characteristics. Maturation processes revealed key residue changes to attain expression, stability, and affinity improvements as compared with the parental scFv. Combination of these changes resulted in the scFv LR, which is capable of rescuing mice from severe envenomation by 3 LD(50) of freshly prepared whole venom of C. noxius (7.5 μg/20 g of mouse) and C. suffusus (26.25 μg/20 g of mouse), with surviving rates between 90 and 100%. Our research is leading to the formulation of an antivenom consisting of a discrete number of human scFvs endowed with strong cross-reactivity and low immunogenicity.

  12. Effect of toxin-g from Tityus serrulatus scorpion venom on gastric emptying in rats

    Directory of Open Access Journals (Sweden)

    F. Bucaretchi

    1999-04-01

    Full Text Available The effect of toxin-g from Tityus serrulatus scorpion venom on the gastric emptying of liquids was studied in 176 young adult male Wistar rats (2-3 months of age divided into subgroups of 8 animals each. Toxin-g was injected iv at doses of 25, 37.5, 50 or 100 µg/kg and the effect on gastric emptying was assessed 30 min and 8 h later. A time-course study was also performed by injecting 50 µg of toxin-g /kg and measuring the effect on gastric emptying at times 0.25, 0.5, 1, 2, 4, 8, 24 and 48 h post-venom. Each envenomed animal was paired with its saline control and all received a saline test meal solution containing phenol red (60 µg/ml as a marker. Ten minutes after administering the test meal by gavage the animals were sacrificed and gastric retention was determined by measuring the residual marker concentration of the test meal. A significant delay in gastric emptying, at 30 min and 8 h post-venom, was observed only after 50 and 100 µg of toxin-g /kg compared to control values. The responses to these two doses were significantly different after 8 h post-venom. Toxin-g (50 µg/kg significantly delayed the gastric emptying of liquids at all times studied, with a peak response at 4 h after toxin administration compared to control values. These results indicate that the iv injection of toxin-g may induce a rapid, intense and sustained inhibition of gastric emptying 0.25 to 48 h after envenomation.

  13. Exploiting Cross-reactivity to Neutralize Two Different Scorpion Venoms with One Single Chain Antibody Fragment*

    Science.gov (United States)

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D.; Becerril, Baltazar

    2011-01-01

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Becerril, B. (2005) FEBS J. 272, 2591–2601) and Css2 (this work). Each evolved variant showed strong cross-reactivity against several toxins, and was capable of neutralizing Cn2 and Css2. Furthermore, each variant neutralized the whole venoms of the above species. As far as we know, this is the first report of antibodies with such characteristics. Maturation processes revealed key residue changes to attain expression, stability, and affinity improvements as compared with the parental scFv. Combination of these changes resulted in the scFv LR, which is capable of rescuing mice from severe envenomation by 3 LD50 of freshly prepared whole venom of C. noxius (7.5 μg/20 g of mouse) and C. suffusus (26.25 μg/20 g of mouse), with surviving rates between 90 and 100%. Our research is leading to the formulation of an antivenom consisting of a discrete number of human scFvs endowed with strong cross-reactivity and low immunogenicity. PMID:21156801

  14. Venom from Opisthacanthus elatus scorpion of Colombia, could be more hemolytic and less neurotoxic than thought.

    Science.gov (United States)

    Estrada-Gómez, Sebastián; Vargas Muñoz, Leidy Johana; Saldarriaga-Córdoba, Mónica; Quintana Castillo, Juan Carlos

    2016-01-01

    We report the first biochemical, biological, pharmacological and partial proteomic characterization studies of the Opisthancanthus elatus venom (Gervais, 1844) from Colombia. The Reverse Phase High-Performance Liquid Chromatography venom profile showed 28 main well-defined peaks, most eluting between 20 and 45min (18-30% of acetonitrile, respectively). High-resolution mass analysis indicates the presence of 106 components ranging from 806.59742Da to 16849.4139Da. O. elatus venom showed hemolytic activity and hydrolyzed the specific substrate BapNa suggesting the presence of proteins with serine-protease activity. Collected RP-HPLC fractions eluting at 52.6, 55.5, 55.8, 56.2, and 63.9min (PLA2 region between 33 and 40% of acetonitrile), showed hemolytic activity and hydrolyzed the synthetic substrate 4-nitro-3-octanoyloxy-benzoic acid, indicating the presence of compounds with phospholipases A2 activity. These RP-HPLC fractions, showed molecular masses values up to 13978.19546Da, corroborating the possible presence of the mentioned enzymes. Tryptic digestion and MS/MS analysis showed the presence of a phospholipase like fragment, similar to on described in other Opisthacanthus genus studies. No coagulant activity was observed. No larvicidal or antimicrobial activity was observed at concentrations evaluated. Lethal and toxic activity is expected at doses above 100mg/kg, no neurotoxic effects were detected at lower doses. In conclusion, O. elatus exhibits a venom with a predominant phospholipase A2 activity than thought; mammal's neurotoxic activity is expected above the 100mg/kg, which is very high compared to the venom from other neurotoxic scorpions.

  15. Chemical engineering and structural and pharmacological characterization of the α-scorpion toxin OD1.

    Science.gov (United States)

    Durek, Thomas; Vetter, Irina; Wang, Ching-I Anderson; Motin, Leonid; Knapp, Oliver; Adams, David J; Lewis, Richard J; Alewood, Paul F

    2013-01-01

    Scorpion α-toxins are invaluable pharmacological tools for studying voltage-gated sodium channels, but few structure-function studies have been undertaken due to their challenging synthesis. To address this deficiency, we report a chemical engineering strategy based upon native chemical ligation. The chemical synthesis of α-toxin OD1 was achieved by chemical ligation of three unprotected peptide segments. A high resolution X-ray structure (1.8 Å) of synthetic OD1 showed the typical βαββ α-toxin fold and revealed important conformational differences in the pharmacophore region when compared with other α-toxin structures. Pharmacological analysis of synthetic OD1 revealed potent α-toxin activity (inhibition of fast inactivation) at Nav1.7, as well as Nav1.4 and Nav1.6. In addition, OD1 also produced potent β-toxin activity at Nav1.4 and Nav1.6 (shift of channel activation in the hyperpolarizing direction), indicating that OD1 might interact at more than one site with Nav1.4 and Nav1.6. Investigation of nine OD1 mutants revealed that three residues in the reverse turn contributed significantly to selectivity, with the triple OD1 mutant (D9K, D10P, K11H) being 40-fold more selective for Nav1.7 over Nav1.6, while OD1 K11V was 5-fold more selective for Nav1.6 than Nav1.7. This switch in selectivity highlights the importance of the reverse turn for engineering α-toxins with altered selectivity at Nav subtypes.

  16. The Effects of a Chactoid Scorpion Venom and Its Purified Toxins on Rat Blood Pressure and Mast Cells Histamine Release

    Directory of Open Access Journals (Sweden)

    Philip Lazarovici

    2013-07-01

    Full Text Available The effect of the venom of the Chactoid family of scorpions on blood pressure was scantly investigated and was addressed in the present study using the venom of the Israeli scorpion, Scorpio maurus palmatus. Blood pressure in rats was monitored via cannulated femoral artery, while venom and toxins were introduced into femoral vein. Venom injection elicited a biphasic effect, expressed first by a fast and transient hypotensive response, which lasted up to 10 min, followed by a hypertensive response, which lasted up to one hour. It was found that these effects resulted from different venom components. Phospholipase A2 produced the hypotensive effect, while a non-enzymatic neurotoxic polypeptide fraction produced the hypertensive effect. Surprisingly, the main neurotoxic polypeptide to mice had no effect on blood pressure. In vitro experiments indicated that the hypertensive factors caused histamine release from the peritoneal mast cells, but this effect is assumed to be not relevant to their in vivo effect. In spite of the cytotoxic activity of phospholipase A2, it did not release histamine. These findings suggest that the effects of venom and isolated fractions on blood pressure parameters are mediated by different mechanisms, which deserve further pharmacological investigation.

  17. Vesicle-associated membrane protein (VAMP) cleavage by a new metalloprotease from the Brazilian scorpion Tityus serrulatus.

    Science.gov (United States)

    Fletcher, Paul L; Fletcher, Maryann D; Weninger, Keith; Anderson, Trevor E; Martin, Brian M

    2010-03-01

    We present evidence that venom from the Brazilian scorpion Tityus serrulatus and a purified fraction selectively cleave essential SNARE proteins within exocrine pancreatic tissue. Western blotting for vesicle-associated membrane protein type v-SNARE proteins (or synaptobrevins) reveals characteristic alterations to venom-treated excised pancreatic lobules in vitro. Immunocytochemistry by electron microscopy confirms both the SNARE identity as VAMP2 and the proteolysis of VAMP2 as a marked decrease in secondary antibody-conjugated colloidal gold particles that are predominantly associated with mature zymogen granules. Studies with recombinant SNARE proteins were used to determine the specific cleavage site in VAMP2 and the susceptibility of VAMP8 (endobrevin). The VAMP2 cleavage site is between the transmembrane anchor and the SNARE motif that assembles into the ternary SNARE complex. Inclusion of divalent chelating agents (EDTA) with fraction nu, an otherwise active purified component from venom, eliminates SNARE proteolysis, suggesting the active protein is a metalloprotease. The unique cleavages of VAMP2 and VAMP8 may be linked to pancreatitis that develops following scorpion envenomation as both of these v-SNARE proteins are associated with zymogen granule membranes in pancreatic acinar cells. We have isolated antarease, a metalloprotease from fraction nu that cleaves VAMP2, and report its amino acid sequence.

  18. Vesicle-associated Membrane Protein (VAMP) Cleavage by a New Metalloprotease from the Brazilian Scorpion Tityus serrulatus*

    Science.gov (United States)

    Fletcher, Paul L.; Fletcher, Maryann D.; Weninger, Keith; Anderson, Trevor E.; Martin, Brian M.

    2010-01-01

    We present evidence that venom from the Brazilian scorpion Tityus serrulatus and a purified fraction selectively cleave essential SNARE proteins within exocrine pancreatic tissue. Western blotting for vesicle-associated membrane protein type v-SNARE proteins (or synaptobrevins) reveals characteristic alterations to venom-treated excised pancreatic lobules in vitro. Immunocytochemistry by electron microscopy confirms both the SNARE identity as VAMP2 and the proteolysis of VAMP2 as a marked decrease in secondary antibody-conjugated colloidal gold particles that are predominantly associated with mature zymogen granules. Studies with recombinant SNARE proteins were used to determine the specific cleavage site in VAMP2 and the susceptibility of VAMP8 (endobrevin). The VAMP2 cleavage site is between the transmembrane anchor and the SNARE motif that assembles into the ternary SNARE complex. Inclusion of divalent chelating agents (EDTA) with fraction ν, an otherwise active purified component from venom, eliminates SNARE proteolysis, suggesting the active protein is a metalloprotease. The unique cleavages of VAMP2 and VAMP8 may be linked to pancreatitis that develops following scorpion envenomation as both of these v-SNARE proteins are associated with zymogen granule membranes in pancreatic acinar cells. We have isolated antarease, a metalloprotease from fraction ν that cleaves VAMP2, and report its amino acid sequence. PMID:20026600

  19. Fine structure of the stinger, histology and histochemistry of the venom gland in the scorpion Androctonus amoreuxi (Buthidae

    Directory of Open Access Journals (Sweden)

    Belal A. Soliman

    2013-03-01

    Full Text Available The venom apparatus of the scorpion Androctonus amoreuxi has been identified histologically and histochemically in the present study. The results showed that this apparatus composed of a pair of venom glands and a stinger located in the terminal segment called telson. The stinger of the venom apparatus has been studied by the light microscope and SEM. The stinger, located at the end section of the telson, is sickle-shaped. The venom is ejected through a pair of venom pores on its subterminal portion. Both venom ducts extend along the stinger without contact with each other since they are separated by connective tissue cells. The stinger is covered by cuticle and spines. Each venom gland is covered by a sheath of striated muscle and is lined with extensively folded secretory epithelium that consists of non-secretory and secretory venom-producing cells. The venom-producing cells reacted positively to histochemical tests for carbohydrates and proteins. The outcomes also revealed that the venom-producing cells of both glands produce neutral mucosubstances. The structure and secretion of scorpion venom glands are discussed within the context of the present results.

  20. Identification of a new specific Kv1.3 channel blocker, Ctri9577, from the scorpion Chaerilus tricostatus.

    Science.gov (United States)

    Xie, Shujun; Feng, Jing; Yu, Congya; Li, Zhi; Wu, Yingliang; Cao, Zhijian; Li, Wenxin; He, Xiaohua; Xiang, Ming; Han, Song

    2012-07-01

    Scorpion toxins are valuable resources for discovering new ion channel modulators and drug candidates. Potassium channel Kv1.3 is an important pharmacological target of T cell-mediated autoimmune diseases, which are encouraging the screening and design of the specific peptide blockers for Kv1.3 channel. Ctri9577, the first neurotoxin gene of Chaerilidae family was cloned from the venom of the scorpion Chaerilus tricostatus through the constructing its cDNA library. The sequence analysis showed that the mature peptide of Ctri9577 contained 39 amino acid residues including six conserved cysteines, whose low sequence similarity indicated that it was a new member of α-KTx15 subfamily. By using expression and purification technology, the recombinant peptide was obtained. Subsequently, the electrophysiological experiments indicated that the Ctri9577 peptide selectively inhibited Kv1.3 channel current with an IC(50) of 0.49±0.45 nM without effectively blocking potassium channels Kv1.1, Kv1.2, hERG and SK3. All these findings not only enrich the knowledge of toxins from the Chaerilidae family, but also present a novel potential drug candidate targeting Kv1.3 channels for the therapy of autoimmune diseases.

  1. The effects of a chactoid scorpion venom and its purified toxins on rat blood pressure and mast cells histamine release.

    Science.gov (United States)

    Ettinger, Keren; Cohen, Gadi; Momic, Tatjana; Lazarovici, Philip

    2013-07-29

    The effect of the venom of the Chactoid family of scorpions on blood pressure was scantly investigated and was addressed in the present study using the venom of the Israeli scorpion, Scorpio maurus palmatus. Blood pressure in rats was monitored via cannulated femoral artery, while venom and toxins were introduced into femoral vein. Venom injection elicited a biphasic effect, expressed first by a fast and transient hypotensive response, which lasted up to 10 min, followed by a hypertensive response, which lasted up to one hour. It was found that these effects resulted from different venom components. Phospholipase A₂ produced the hypotensive effect, while a non-enzymatic neurotoxic polypeptide fraction produced the hypertensive effect. Surprisingly, the main neurotoxic polypeptide to mice had no effect on blood pressure. In vitro experiments indicated that the hypertensive factors caused histamine release from the peritoneal mast cells, but this effect is assumed to be not relevant to their in vivo effect. In spite of the cytotoxic activity of phospholipase A₂, it did not release histamine. These findings suggest that the effects of venom and isolated fractions on blood pressure parameters are mediated by different mechanisms, which deserve further pharmacological investigation.

  2. First chemical synthesis of a scorpion alpha-toxin affecting sodium channels: the Aah I toxin of Androctonus australis hector.

    Science.gov (United States)

    M'Barek, Sarrah; Fajloun, Ziad; Cestèle, Sandrine; Devaux, Christiane; Mansuelle, Pascal; Mosbah, Amor; Jouirou, Besma; Mantegazza, Massimo; Van Rietschoten, Jurphaas; El Ayeb, Mohamed; Rochat, Hervé; Sabatier, Jean-Marc; Sampieri, François

    2004-11-01

    Aah I is a 63-residue alpha-toxin isolated from the venom of the Buthidae scorpion Androctonus australis hector, which is considered to be the most dangerous species. We report here the first chemical synthesis of Aah I by the solid-phase method, using a Fmoc strategy. The synthetic toxin I (sAah I) was renatured in DMSO-Tris buffer, purified and subjected to thorough analysis and comparison with the natural toxin. The sAah I showed physico-chemical (CD spectrum, molecular mass, HPLC elution), biochemical (amino-acid composition, sequence), immunochemical and pharmacological properties similar to those of the natural toxin. The synthetic toxin was recognized by a conformation-dependent monoclonal anti-Aah I antibody, with an IC50 value close to that for the natural toxin. Following intracerebroventricular injection, the synthetic and the natural toxins were similarly lethal to mice. In voltage-clamp experiments, Na(v) 1.2 sodium channel inactivation was inhibited by the application of sAah I or of the natural toxin in a similar way. This work describes a simple protocol for the chemical synthesis of a scorpion alpha-toxin, making it possible to produce structural analogues in time.

  3. Scorpion toxin prolongs an inactivation phase of the voltage-dependent sodium current in rat isolated single hippocampal neurons.

    Science.gov (United States)

    Kaneda, M; Oyama, Y; Ikemoto, Y; Akaike, N

    1989-05-15

    The effects of scorpion toxin on the voltage-dependent sodium current (INa) of CA1 pyramidal neurons isolated from rat hippocampus were studied under the single-electrode voltage-clamp condition using a 'concentration-clamp' technique. The toxin increased the peak amplitude of INa and prolonged its inactivation phase in a time- and dose-dependent manner. Inactivation phase of INa proceeded with two exponential components in the absence (control) and presence of the toxin. In the toxin-treated neurons, both the time constant of slow component and its fractional contribution to the total current increased dose-dependently while the fractional contribution of the fast one decreased in a dose-dependent fashion without changing its time constant. Actions of scorpion toxin on the sodium channels of hippocampal pyramidal neurons were essentially similar to those of peripheral preparations. Therefore, it can be concluded that the sodium channels of mammalian brain neurons have structures and functions similar to peripheral channels.

  4. Genomic organization of four novel nondisulfide-bridged peptides from scorpion Mesobuthus martensii Karsch: gaining insight into evolutionary mechanism.

    Science.gov (United States)

    Luo, Feng; Zeng, Xian-Chun; Hahin, Richard; Cao, Zhi-Jian; Liu, Hui; Li, Wen-Xin

    2005-12-01

    At least 25 nondisulfide-bridged peptides (NDBPs) have been identified and characterized from scorpions. However, the genomic organization of the genes that encode these peptides have not been reported yet. BmKa1, BmKa2 and BmKb1 are three novel genes that code for NDBPs identified by our group from Mesobuthus martensii Karsch. Based on their cDNA sequences, the genomic DNA sequences encoding these peptides were obtained using the PCR method. Sequence analysis showed that three distinct genomic structural patterns are used to encode these three peptides. The BmKa1 gene is not interrupted by any introns. However, the BmKa2 gene is composed of two exons, interrupted by a 67 bp intron that is located in the DNA region encoding the mature peptide. Two genomic homologues of the BmKb1 cDNA sequence, named BmKb1' and BmKb2, respectively, were obtained. The BmKb1' gene contains one intron of 593 bp, inserted into the DNA region that encodes the signal peptide. Similarly, the BmKb2 gene also contains an intron that interrupts the exon that encodes the NDBP signal peptide. The amino acid sequences deduced for BmKb2 and BmKb1' differ only at one position. The data suggest that the genomic organizational pattern of NDBPs displays more divergence than that exhibited by the genes that encode disulfide-bridged peptides from scorpions.

  5. Differential effects of defined chemical modifications on antigenic and pharmacological activities of scorpion alpha and beta toxins.

    Science.gov (United States)

    el Ayeb, M; Darbon, H; Bahraoui, E M; Vargas, O; Rochat, H

    1986-03-03

    Specific chemical modifications of scorpion alpha and beta toxins have been used to study the involvement of particular residues in both the pharmacological and the antigenic sites of these toxins. Modification by 1,2-cyclohexanedione of arginine-27 of a beta toxin, Centruroides suffusus suffusus toxin II, drastically decrease the antigenic activity without any influence on the pharmacological activity. Conversely, modification by the same reagent of arginine-2 of an alpha toxin, Androctonus australis Hector toxin III, led to a 100-times less pharmacologically potent derivative and did not induce a significant loss of antigenic activity. Excision of the N-terminal pentapeptide of another alpha toxin, Buthus occitanus mardochei toxin III, by pepsin digestion led to a non-toxic derivative retaining full antigenic activity. Thus, the N-terminal part of the conserved hydrophobic surface of the toxin is highly implicated in the pharmacological activity, whereas the region of arginine-27, located in the alpha helix situated on the back surface, opposite the conserved hydrophobic region, is fully implicated in the antigenic activity and is far from the pharmacological site. These results are good arguments in favor of the idea that in scorpion toxins the surfaces implicated in the pharmacological and the antigenic activities do not overlap. Since the antigenic sites are present in highly variable sequence the development of an efficient polyvalent serotherapy is questionable.

  6. Isolation and primary structure of a potent toxin from the venom of the scorpion Centruroides sculpturatus Ewing.

    Science.gov (United States)

    Pete, M J; Conlon, J M; Murphy, R F

    1992-12-01

    A potent toxin has been purified from the venom of the scorpion Centruroides sculpturatus Ewing using the ion-exchange resin CM-Sepharose CL-6B at basic pH. The toxin, designated CsE M1, comprised 65 amino acid residues and its primary structure was established as: Lys-Glu-Gly-Tyr-Leu-Val-Asn-Ser-Tyr-Thr10-Gly-Cys-Lys-Tyr-Glu-Cys- Leu-Lys-Leu- Gly20-Asp-Asn-Asp-Tyr-Cys-Leu-Arg-Glu-Cys-Arg30-Gln-Gln-Tyr- Gly-Lys-Ser-Gly-Gly - Tyr-Cys40-Tyr-Ala-Phe-Ala-Cys-Trp-Cys-Thr-His-Leu50-Tyr-Glu- Gln-Ala-Val-Val-Trp - Pro-Leu-Pro60-Asn-Lys-Thr-Cys-Asn. CsE M1 is the most lethal protein to be identified in C. sculpturatus venom and the LD50 of the toxin, determined by subcutaneous injection into Swiss mice, is 87 micrograms/kg. CsE M1 shows strong structural similarity (92% positional identity) to the most potent beta-toxin, Css II, from the Mexican scorpion, Centruroides suffusus suffusus but is quite dissimilar to the previously characterized toxins with low potency isolated from C. sculpturatus Ewing.

  7. Isolation and molecular cloning of beta-neurotoxins from the venom of the scorpion Centruroides suffusus suffusus.

    Science.gov (United States)

    Espino-Solis, Gerardo Pavel; Estrada, Georgina; Olamendi-Portugal, Timoteo; Villegas, Elba; Zamudio, Fernando; Cestele, Sandrine; Possani, Lourival D; Corzo, Gerardo

    2011-04-01

    This communication reports the identification and characterization of two new toxins from the venom of the scorpion Centruroides suffusus suffusus, named: CssVIII and CssIX, according to the original nomenclature of toxins previously described for this scorpion. The isolation was obtained by means of two chromatographic steps, and a cDNA library was used to fully identify their precursors. CssVIII and CssIX contain signal peptides of 19 and 17 amino acid residues, and mature peptides of 66 and 65 residues, respectively. Intracranial injections into mice of both purified toxins showed toxicity results similar to those found for toxins CssII and CssIV. Additionally, they compete with the parent toxin CssIV, in binding and displacement experiments, conducted with brain synaptosomes showing nanomolar affinities. These results strongly support the conclusion that they are new β-neurotoxins and certainly would be of the interest of researchers in the field of venomics for studying sodium channels.

  8. General characterization of Tityus fasciolatus scorpion venom. Molecular identification of toxins and localization of linear B-cell epitopes.

    Science.gov (United States)

    Mendes, T M; Guimarães-Okamoto, P T C; Machado-de-Avila, R A; Oliveira, D; Melo, M M; Lobato, Z I; Kalapothakis, E; Chávez-Olórtegui, C

    2015-06-01

    This communication describes the general characteristics of the venom from the Brazilian scorpion Tityus fasciolatus, which is an endemic species found in the central Brazil (States of Goiás and Minas Gerais), being responsible for sting accidents in this area. The soluble venom obtained from this scorpion is toxic to mice being the LD50 is 2.984 mg/kg (subcutaneally). SDS-PAGE of the soluble venom resulted in 10 fractions ranged in size from 6 to 10-80 kDa. Sheep were employed for anti-T. fasciolatus venom serum production. Western blotting analysis showed that most of these venom proteins are immunogenic. T. fasciolatus anti-venom revealed consistent cross-reactivity with venom antigens from Tityus serrulatus. Using known primers for T. serrulatus toxins, we have identified three toxins sequences from T. fasciolatus venom. Linear epitopes of these toxins were localized and fifty-five overlapping pentadecapeptides covering complete amino acid sequence of the three toxins were synthesized in cellulose membrane (spot-synthesis technique). The epitopes were located on the 3D structures and some important residues for structure/function were identified.

  9. Recombination of Anti-pain Scorpion Toxin Polypeptides%抗痛蝎毒素多肽的重组表达研究

    Institute of Scientific and Technical Information of China (English)

    冉秋行; 刘霞; 杨清湖; 白占涛

    2015-01-01

    蝎毒素多肽作用于众多细胞膜离子通道,调控通道动力学特性.显具抗痛活性的蝎毒素多肽呈现较高的学术研究价值和医药应用前景.序列比对分析发现,抗痛蝎毒素多肽具较高保守型,序列同源性达45%,均具8个半胱氨酸残基,且其位置相对保守,这可能与抗痛功能有关.天然蝎毒素蛋白的获得、结构与功能研究受限,而高纯度、高活性重组毒素多肽是一条有效解决途径.本文综述抗痛蝎毒素多肽的重组表达,藉此推进其结构与功能相关性的理解.%Scorpion toxin peptides target on and regulate gating dynamics of multiple ion channels. Anti-pain scor-pion toxin polypeptides are a kind of potential analgesic drugs. Sequence alignment analysis showed that the anti-scorpion toxin polypeptide performed about 45% sequence homology and three dimensional topology all combined by eight conservative scaffold cysteine residues,which may be corresponding to their anti-pain function. Moreover, gene recombinant and mutation of high-purity and high-activity polypeptides would be the more effective path-ways to elucidate the conservation and active properties. The paper thus reviews the current recombination progress-ing and application of scorpion polypeptides to further our understanding to the structure-function relationship of natural anti-pain scorpion toxins.

  10. Pre-clinical studies of toxin-specific nanobodies: evidence of in vivo efficacy to prevent fatal disturbances provoked by scorpion envenoming.

    Science.gov (United States)

    Hmila, Issam; Cosyns, Bernard; Tounsi, Hayfa; Roosens, Bram; Caveliers, Vicky; Abderrazek, Rahma Ben; Boubaker, Samir; Muyldermans, Serge; El Ayeb, Mohamed; Bouhaouala-Zahar, Balkiss; Lahoutte, Tony

    2012-10-15

    Scorpions represent a significant threat to humans and animals in various countries throughout the world. Recently, we introduced Nanobodies (Nbs) to combat more efficiently scorpion envenoming and demonstrated the performance of NbAahIF12 and NbAahII10 to neutralize scorpion toxins of Androctonus australis hector venom. A bispecific Nb construct (NbF12-10) comprising these two Nbs is far more protective than the classic Fab'(2) based therapy and is the most efficient antivenom therapy against scorpion sting in preclinical studies. Now we investigate the biodistribution and pharmacokinetics of (99m)Tc labeled Nbs by in vivo imaging in rodents and compared these data with those of the Fab'(2) product (PAS). The pharmacodynamics of the Nbs was investigated in rats by in vivo echocardiography and it is shown that NbF12-10 prevents effectively the hemodynamic disturbances induced by a lethal dose of venom. Moreover, even a late injection of NbF12-10 restores the heart rate and brings the blood pressure to baseline values. Histology confirms that NbF12-10 prevents lung and heart lesions of treated mice after envenoming. In conjunction, in this preclinical study, we provide proof of concept that NbF12-10 prevents effectively the fatal disturbances induced by Androctonus venom, and that the Nanobody based therapeutic has a potential to substitute the classic Fab'(2) based product as immunotherapeutic in scorpion envenoming. Further clinical study using larger cohorts of animals should be considered to confirm the full protecting potential of our NbF12-10.

  11. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

    Science.gov (United States)

    Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

  12. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

    Directory of Open Access Journals (Sweden)

    Felipe J Fuzita

    Full Text Available Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability, zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also

  13. Synthesis and characterization of Pi4, a scorpion toxin from Pandinus imperator that acts on K+ channels.

    Science.gov (United States)

    M'Barek, Sarrah; Mosbah, Amor; Sandoz, Guillaume; Fajloun, Ziad; Olamendi-Portugal, Timoteo; Rochat, Hervé; Sampieri, François; Guijarro, J Iñaki; Mansuelle, Pascal; Delepierre, Muriel; De Waard, Michel; Sabatier, Jean-Marc

    2003-09-01

    Pi4 is a 38-residue toxin cross-linked by four disulfide bridges that has been isolated from the venom of the Chactidae scorpion Pandinus imperator. Together with maurotoxin, Pi1, Pi7 and HsTx1, Pi4 belongs to the alpha KTX6 subfamily of short four-disulfide-bridged scorpion toxins acting on K+ channels. Due to its very low abundance in venom, Pi4 was chemically synthesized in order to better characterize its pharmacology and structural properties. An enzyme-based cleavage of synthetic Pi4 (sPi4) indicated half-cystine pairings between Cys6-Cys27, Cys12-32, Cys16-34 and Cys22-37, which denotes a conventional pattern of scorpion toxin reticulation (Pi1/HsTx1 type). In vivo, sPi4 was lethal after intracerebroventricular injection to mice (LD50 of 0.2 microg per mouse). In vitro, addition of sPi4 onto Xenopus laevis oocytes heterologously expressing various voltage-gated K+ channel subtypes showed potent inhibition of currents from rat Kv1.2 (IC50 of 8 pm) and Shaker B (IC50 of 3 nm) channels, whereas no effect was observed on rat Kv1.1 and Kv1.3 channels. The sPi4 was also found to compete with 125I-labeled apamin for binding to small-conductance Ca(2+)-activated K+ (SK) channels from rat brain synaptosomes (IC50 value of 0.5 microm). sPi4 is a high affinity blocker of the Kv1.2 channel. The toxin was docked (BIGGER program) on the Kv channel using the solution structure of sPi4 and a molecular model of the Kv1.2 channel pore region. The model suggests a key role for residues Arg10, Arg19, Lys26 (dyad), Ile28, Lys30, Lys33 and Tyr35 (dyad) in the interaction and the associated blockage of the Kv1.2 channel.

  14. Comprehensive analysis of venom from the scorpion Centruroides tecomanus reveals compounds with antimicrobial, cytotoxic, and insecticidal activities.

    Science.gov (United States)

    Valdez-Velazquéz, L L; Romero-Gutierrez, M T; Delgado-Enciso, I; Dobrovinskaya, O; Melnikov, V; Quintero-Hernández, V; Ceballos-Magaña, S G; Gaitan-Hinojosa, M A; Coronas, F I; Puebla-Perez, A M; Zamudio, F; De la Cruz-García, I; Vázquez-Vuelvas, O F; Soriano-Hernandez, A D; Possani, L D

    2016-08-01

    Centruroides tecomanus is a medically important scorpion of the state of Colima (Mexico). This communication reports the identification of venom components of this scorpion with biological activity over insects/crickets (Acheta domestica), crustaceans/fresh water shrimps (Cambarellus montezumae), and mammalians/mice (Mus musculus, strain CD1). It also describes the pharmacological effects on cell lines in culture (L5178Y cells, HeLa cells, HuTu cells and Jurkat E6-1 cells), as well as on several types of bacteria (see below). The soluble venom of this scorpion was fractionated by high-performance liquid chromatography (HPLC) and collected separately in twelve independent fractions collected over 60 min run (5 min time apart each other). The HPLC components of fraction VII were lethal to all three species used for assay. The IVth fraction had a toxic effect on freshwater shrimps. In this species, fractions VI, VII and VIII were all lethal. For crickets, fractions V and VI were toxic and fraction VII was lethal. In mouse, the lethal components were found in fraction VII, whereas fraction VIII was toxic, but not lethal, at the doses assayed. The molecular weight of peptides from the various group of fractions were identified by mass spectrometry determination. Components lethal to mice showed molecular weights from 7013 to 7487 Da. Two peptides were obtained in homogeneous form and shown to be lethal to the three species of animal used for assay. The soluble venom tested on L5178Y cell line survival was shown to be cytotoxic, at 10-100 μg/mL concentration, when compared to control murine splenocytes (p = 0.007). The soluble venom applied to Hela, Hutu and Jurkat cell lines did not show cytotoxic effects at these concentrations. On the contrary, it seems to have a proliferative effect. However the HPLC fractions I, III, VI and XII do have a cytotoxic effect on Jurkat E06-1 cells in culture at 200 μg/mL concentration. The antimicrobial activity of the venom

  15. Characterization of the first K⁺ channel blockers from the venom of the Moroccan scorpion Buthus occitanus Paris.

    Science.gov (United States)

    Martin-Eauclaire, Marie-France; Céard, Brigitte; Belghazi, Maya; Lebrun, Régine; Bougis, Pierre E

    2013-12-01

    The availability of a large variety of specific blockers, which inhibit different K(+) currents, would help to elucidate their differences in physiological function. Short peptide toxins isolated from scorpion venoms are able to block voltage-dependent or Ca(2+)-activated K(+) channels. Here, we have studied the venom of the Moroccan scorpion Buthus occitanus Paris (BoP) in order to find new peptides, which could enlarge our structure-function relationship knowledge on the Kv1.3 blocker Kaliotoxin (KTX) that belongs to the α-KTx3.1 family. Indeed and since more a decade, KTX is widely used by international investigators because it exhibits a quite sharp specificity and a high-affinity for the Kv1.3 channel, which is not only a neuronal channel but also a therapeutic target for diverse autoimmune diseases such as multiple sclerosis, type 1 diabetes, and rheumatoid arthritis. The BoP venom was first investigated using HPLC and MALDI-TOF/MS. Further, the HPLC fractions were screened by ELISA with antibodies raised against KTX. These antibodies recognized at least three components toxic in mice by intracerebroventricular injection. They were further pharmacologically characterized by competition using (125)I-KTX bound to its specific binding sites on rat brain synaptosomes. A single component (4161 Da) inhibited totally the (125)I-KTX binding and with high-affinity (IC50 = 0.1 nM), while the two other components poorly competed with (IC50 > 100 nM). These toxins were sequenced in full by Edman's degradation. The high-affinity ligand (BoPKTX) shares 86% sequence identity with KTX and was classified as toxin α-KTx3.17. The two others peptides (BoP1 and BoP2, 4093 Da and 4121 Da, respectively) only differ by a Lys/Arg mutation. Their amino acid sequences were related to Martentoxin, which has been characterized from the Chinese scorpion Buthus martenzi Karch and described as both a BKCa and Kv1.3 blocker. Accordingly, they belong to the α-KTx16 family.

  16. Scorpion toxins from Buthus martensii Karsch all possess a predicted alpha-tight-turn.

    Science.gov (United States)

    Hahin, Richard; Chen, Ziyi; Wang, Danhui; Reddy, Giridher; Mao, Long

    2003-01-01

    We have purified a new toxin (BmK 17[4]) from Asian scorpion (Buthus martensii Karsch) venom that possesses a distinctive structural motif in its N-terminal (positions 8-12) that is similarly found in two other previously described alpha-like toxins. BmK 17[4] prolongs action potentials (APs) in frog nerve and was purified using gel filtration, ion exchange, fast protein liquid chromatography (FPLC), and high-performance liquid chromatography (HPLC). BmK 17[4] significantly prolonged frog APs but it did not alter APs from an insect ventral nerve cord at similar doses. When applied to voltage-clamped frog muscle single fibers, BmK 17[4] prolonged fast inactivation. Because the polypeptide prolongs APs when both K+ and Ca2+ channels were blocked, BMK 17[4] acts to selectively alter Na+ channel inactivation. The N-terminal sequence of BmK 17[4] was found to be VRDAYIAKPENCVYXC --. The molar mass of BmK 17[4] was determined by LC/MS/MS to be 7097 Daltons. The N- terminal motif (KPENC), which introduces a reverse turn in residues 8-12, does not appear in previously characterized BmK alpha-toxins and may be characteristic of alpha-like toxins. Sequence similarity database searches were used to test whether the N-terminal sequences of alpha-like polypeptide toxins from B. martensii Karsch possess a distinctive structural motif in its 5-residue reverse turn (alpha-turn) that is conserved. Sequence similarities with putative polypeptides encoded by cDNAs obtained from a cDNA library [Zhu, S. Y., Li, W. X., Zenq, X. C., et al. (2000) Nine novel precursors of Buthus martensii scorpiox alpha-toxin homologues. Toxicon 38, 1653-1661] from BmK venom glands showed that an active polypeptide toxin cleaved from the putative propolypeptide toxin BmK M9 is likely identical to BmK 17[4]. Sequence comparisons with toxins and putative toxins from B. martensii Karsch and other species revealed that a group of these toxins possess a common structural motif in their alpha-turn. A neighbor

  17. Venom conjugated polylactide applied as biocompatible material for passive and active immunotherapy against scorpion envenomation.

    Science.gov (United States)

    Ayari-Riabi, Sana; Trimaille, Thomas; Mabrouk, Kamel; Bertin, Denis; Gigmes, Didier; Benlasfar, Zakaria; Zaghmi, Ahlem; Bouhaouala-Zahar, Balkiss; Elayeb, Mohamed

    2016-04-04

    Scorpion envenoming represents a public health issue in subtropical regions of the world. Treatment and prevention need to promote antitoxin immunity. Preserving antigenic presentation while removing toxin effect remains a major challenge in toxin vaccine development. Among particulate adjuvant, particles prepared with poly (D,L-lactide) polymer are the most extensively investigated due to their excellent biocompatibility and biodegradability. The aim of this study is to develop surfactant-free PLA nanoparticles that safely deliver venom toxic fraction to enhance specific immune response. PLA nanoparticles are coated with AahG50 (AahG50/PLA) and BotG50 (BotG50/PLA): a toxic fraction purified from Androctonus australis hector and Buthus occitanus tunetanus venoms, respectively. Residual toxicities are evaluated following injections of PLA-containing high doses of AahG50 (or BotG50). Immunization trials are performed with the detoxified fraction administered alone without adjuvant. A comparative study of the effect of Freund is also included. The neutralizing capacity of sera is determined in naive mice. Six months later, immunized mice are challenged subcutaneously with increased doses of AahG50. Subcutaneous lethal dose 50 (LD50) of AahG50 and BotG50 is of 575 μg/kg and 1300 μg/kg respectively. By comparison, BotG50/PLA is totally innocuous while 50% of tested mice survive 2875 μg AahG50/kg. Alhydrogel and Freund are not able to detoxify such a high dose. Cross-antigenicity between particulate and soluble fraction is also, ensured. AahG50/PLA and BotG50/PLA induce high antibody levels in mice serum. The neutralizing capacity per mL of anti-venom was 258 μg/mL and 186 μg/mL calculated for anti-AahG50/PLA and anti-BotG50/PLA sera, respectively. Animals immunized with AahG50/PLA are protected against AahG50 injected dose of 3162 μg/kg as opposed all non-immunized mice died at this dose. We find that the detoxification approach based PLA nanoparticles, benefit

  18. Characterization of a novel cDNA encoding a short venom peptide derived from venom gland of scorpion Buthus martensii Karsch: trans-splicing may play an important role in the diversification of scorpion venom peptides.

    Science.gov (United States)

    Zeng, Xian-Chun; Luo, Feng; Li, Wen-Xin

    2006-04-01

    A novel cDNA clone (named BmKT-u) which is a hybrid molecule of the 5'-terminal region of BmKT' cDNA and the 3'-terminal region of an undocumented cDNA (named BmKu), was isolated from a cDNA library made from the venom gland of scorpion Buthus martensii Karsch. BmKT-u codes for a 30 amino acid residue precursor peptide composed of a 20-residue signal sequence, and a putative 10-residue novel mature peptide. Northern blot hybridization showed BmKT-u cDNA is generated from a transcript. RT-PCR experiments excluded the possibility that BmKT-u cDNA is an artifact generated during reverse transcription. Genomic amplifications performed with three pairs of BmKT-u gene-specific primers showed the BmKT-u gene does not exist in the genome of the scorpion as a single transcriptional unit. Genomic cloning for BmKT' showed that the BmKT' gene contains an intron of 509 bp inserted into the region encoding the C-terminal region of the signal peptide. A sequence alignment comparison of the cDNA of BmKT-u with genomic BmKT' revealed that the junction site of the hybrid molecule is located at the 5'-splicing site of the intron. The data suggest that the BmKT-u transcript is a naturally occurring mature mRNA that is generated by trans-splicing. Trans-splicing may contribute to the diversity of venom peptides from venomous animals.

  19. Characterization of BmKbpp, a multifunctional peptide from the Chinese scorpion Mesobuthus martensii Karsch: gaining insight into a new mechanism for the functional diversification of scorpion venom peptides.

    Science.gov (United States)

    Zeng, Xian-Chun; Wang, Sanxia; Nie, Yao; Zhang, Lei; Luo, Xuesong

    2012-01-01

    BmKbpp is a novel cationic and α-helical peptide from the Chinese scorpion Mesobuthus martensii Karsch, of which function or biological activity has not been characterized so far. Here we showed that BmKbpp possesses strong antimicrobial activity against both Gram-positive and Gram-negative bacteria with a MIC range from 2.3 μM to 68.2 μM for the majority of tested bacteria. BmKbpp also inhibits the growth of tested fungi with an IC50 range from 0.2 μM to 3.1 μM. Because BmKbpp potently inhibits the growth of some antibiotics-resistant pathogens, and shows very weak hemolytic activity, it has considerable potentials for therapeutic applications. Moreover, we found that BmKbpp markedly inhibits the superoxide production in granulocytes or HL-60 cells at the concentrations of submicromolar level; this suggests that BmKbpp can act as a signaling molecule involving innate immune regulation at low concentrations. The C-terminal region of BmKbpp (BmKbpp-C) shows 72% similarity to the peptide K-12, a bradykinin-potentiating peptide. We found that both BmKbpp and BmKbpp-C possess bradykinin-potentiating activity, and the activity of BmKbpp-C is stronger than that of BmKbpp. PCR amplification for the genomic gene of BmBpp showed that it is not a continuous sequence in the genome; it suggests that BmKbpp could come from a recombination event in transcript level. Taken together, our data suggest that multi-functionalization of a single peptide, which is probably mediated by trans-splicing, could be a new mechanism for the functional diversification of scorpion venom peptides.

  20. Gene cloning and functional characterization of four novel antimicrobial-like peptides from scorpions of the family Vaejovidae.

    Science.gov (United States)

    Ramírez-Carreto, Santos; Quintero-Hernández, Verónica; Jiménez-Vargas, Juana María; Corzo, Gerardo; Possani, Lourival D; Becerril, Baltazar; Ortiz, Ernesto

    2012-04-01

    From the cDNA libraries made from the venom glands of two scorpions belonging to the Vaejovidae family, four different putative non disulfide-bridged antimicrobial peptides were identified: VmCT1 and VmCT2 from Vaejovis mexicanus smithi plus VsCT1 and VsCT2 from Vaejovis subcristatus. These short peptides (with only 13 amino acid residues each) share important amino acid sequence similarities among themselves and with other reported antimicrobial peptides, but their biological activities vary dramatically. This communication reports the cloning, chemical synthesis and characterization of these peptides. Two peptides, VmCT1 and VmCT2 showed broad-spectrum antibacterial activity with minimum inhibitory concentrations MICs in the range of 5-25 μM and 10-20 μM respectively, whereas their hemolytic activity at these concentrations was low. Structure-function relationships that might determine the differences in activities are discussed.

  1. The development of the hardware for studying biological clock systems under microgravity conditions, using scorpions as animal models

    Science.gov (United States)

    Serafini, L.; Viganò, W.; Donati, A.; Porciani, M.; Zolesi, V.; Schulze-Varnholt, D.; Manieri, P.; El-Din Sallam, A.; Schmäh, M.; Horn, E. R.

    2007-02-01

    The study of internal clock systems of scorpions in weightless conditions is the goal of the SCORPI experiment. SCORPI was selected for flight on the International Space Station (ISS) and will be mounted in the European facility BIOLAB, the European Space Agency (ESA) laboratory designed to support biological experiments on micro-organisms, cells, tissue, cultures, small plants and small invertebrates. This paper outlines the main features of a breadboard designed and developed in order to allow the analysis of critical aspects of the experiment. It is a complete tool to simulate the experiment mission on ground and it can be customised, adapted and tuned to the scientific requirements. The paper introduces the SCORPI-T experiment which represents an important precursor for the success of the SCORPI on BIOLAB. The capabilities of the hardware developed show its potential use for future similar experiments in space.

  2. Synthesis and structural characterization of two half-sandwich nickel(II) complexes with the scorpionate ligands

    Energy Technology Data Exchange (ETDEWEB)

    Wang, G.-F., E-mail: wgf1979@126.com, E-mail: s-shuwen@163.com [Yuncheng University, Department of Applied Chemistry (China); Zhang, X., E-mail: zhangx@hit.edu.cn [Harbin Institute of Technology, Academy of Fundamental and Interdisciplinary Science (China); Sun, S.-W.; Sun, H.; Ma, H.-X. [Yuncheng University, Department of Applied Chemistry (China)

    2015-12-15

    The synthesis and characterization of two new halfsandwich mononuclear nickel(II) complexes with the scorpionate ligands, [k{sup 3}-N, N',N''-Tp{sup t-Bu}, {sup Me}NiI] (1) and [k{sup 3}-N,N',N''-Tp{sup t-Bu}, {sup Me}NiNO{sub 3}] (2), are reported. These complexes have been fully characterized by elemental analyses and infrared spectra. Their molecular structures were determined by single crystal X-ray diffraction. The nickel(II) ion of complex 1 is in a four-coordinate environment, in which the donor atoms are provided by three nitrogen atoms of a hydrotris(pyrazolyl) borate ligand and one iodide atom, while that of complex 2 is in a five-coordinate environment with three nitrogen atoms from a hydrotris(pyrazolyl)borate ligand and two oxygen atoms from a nitrate ion.

  3. Molecular modeling and docking simulations of scorpion toxins and related analogs on human SKCa2 and SKCa3 channels.

    Science.gov (United States)

    Andreotti, Nicolas; di Luccio, Eric; Sampieri, François; De Waard, Michel; Sabatier, Jean-Marc

    2005-07-01

    The small-conductance Ca2+-activated K+ (SKCa) channels modulate cytosolic Ca2+ concentration in excitable and non-excitable tissues by regulating the membrane potential and are responsible of slow action potential after hyperpolarization that inhibits cell firing. Among these, human SKCa2 and SKCa3 channels differ in the pore region by only two residues: Ala331 and Asn367 (human small-conductance calcium-activated potassium channel, hSKCa2) instead of Val485 and His521 (hSKCa3). To design highly selective blockers of hSKCa channels, a number of known hSKCa2 and/or hSKCa3-active peptides (i.e. scorpion toxins and analogs thereof) were analyzed for their interactions and selectivities toward these channels. Molecular models of hSKCa2 and hSKCa3 channels (S5-H5-S6 portion) were generated, and scorpion toxins/peptides of unsolved three-dimensional (3D) structures were modeled. Models of toxin-channel complexes were generated by the bimolecular complex generation with global evaluation, and ranking (BiGGER) docking software and selected by using a screening method of the docking solutions. A high degree of correlation was found to exist between docking energies and experimental Kd values of peptides that blocked hSKCa2 and/or hSKCa3 channels, suggesting it could be appropriate to predict Kd values of other bioactive peptides. The best scoring complexes were also used to identify key residues of both interacting partners, indicating that such an approach should help the design of more active and/or selective peptide blockers of targeted ion channels.

  4. Negative-shift activation, current reduction and resurgent currents induced by β-toxins from Centruroides scorpions in sodium channels.

    Science.gov (United States)

    Schiavon, Emanuele; Pedraza-Escalona, Martha; Gurrola, Georgina B; Olamendi-Portugal, Timoteo; Corzo, Gerardo; Wanke, Enzo; Possani, Lourival D

    2012-02-01

    The β-toxins purified from the New World scorpion venoms of the Centruroides species affect several voltage-gated sodium channels (VGSCs) and thus are essential tools not only for the discrimination of different channel sub-types but also for studying the structure-function relationship between channels and toxins. This communication reports the results obtained with four different peptides purified from three species of Centruroides scorpions and assayed on seven distinct isoforms of VGSC (Na(v)1.1-Na(v)1.7) by specific functional analysis conducted through single cell electrophysiology. The toxins studied were CssII from Centruroides suffusus suffusus, Cll1 and Cll2 from Centruroides limpidus limpidus and a novel toxin from Centruroides noxius, which was characterized for the first time here. It has 67 amino acid residues and four disulfide bridges with a molecular mass of 7626 Da. Three different functional features were identified: current reduction of macroscopic conductance, left shift of the voltage-dependent activation and induction of resurgent currents at negative voltages following brief, strong depolarizations. The isoforms which revealed to be more affected resulted to be Na(v)1.6 > 1.1 > 1.2 and, for the first time, a β-toxin is here shown to induce resurgent current also in isoforms different from Na(v)1.6. Additionally, these results were analyzed with molecular modelling. In conclusion, although the four toxins have a high degree of identity, they display tri-modal function, each of which shows selectivity among the different sub-types of Na+ -channels. Thus, they are invaluable as tools for structure-function studies of β-toxins and offer a basis for the design of novel ion channel-specific drugs.

  5. Effect of acid secretion blockade on acute gastric mucosal lesions induced by Tityus serrulatus scorpion toxin in anaesthetized rats.

    Science.gov (United States)

    Melo, Júnio Rios; de Araújo, Gnana Keith Marques; da Luz, Magda Maria Profeta; da Conceição, Sérgio Alexandre; Lisboa, Felipe Assis; Moraes-Santos, Tasso; Cunha-Melo, José Renan

    2006-10-01

    Scorpion venom (TX) promotes gastric acid and pepsin secretion leading to acute gastric mucosal lesions (AGML), when injected in animals. The goal of the present study was to observe the effects of acid gastric secretion blockers over the incidence of TX-induced AGML in vivo. To verify this model, we used male albino rats, fasted 18-20 h (n=122) and anaesthetized with urethane (1.4 g/kg, i.p.). Their trachea and left femoral vein were both cannulated; the first to avoid airway obstructions during scorpion intoxication and the second for administration of saline, TX and acid blockers. Following the surgical procedure, the animals were divided in 10 groups of at least 10 animals each. Control groups were injected with NaCl 0.9% 1 ml/kg (n=10) or TX 375 microg/kg (n=32). Test groups (n=10, each) received atropine 5 mg/kg, cimetidine 10mg/kg, ranitidine 2.5mg/kg, ranitidine 5mg/kg, omeprazol 1 mg/kg, omeprazol 4 mg/kg, octreotide 80 and octreotide 100 microg/kg 10 min before the TX was injected. After 1h of intoxication, the stomach was resected for macroscopic study and the gastric secretion was collected for volume, pH and acid output assessment. We observed that all blockers were able to completely or partially prevent the TX-induced acid secretion as well as the AGML (p<0.05). Our data suggest the TX-induced AGML can be prevented by different class of acid blockers injected before the intoxication.

  6. Mortality and antibody responses of mice to three successive episodes of experimental scorpion (Centruroides limpidus limpidus) envenomation and immunological rescue.

    Science.gov (United States)

    Padilla, Alejandro; Govezensky, Tzipe; Possani, Lourival D; Larralde, Carlos

    2005-08-01

    Mortality rates of mice and their levels of anti-venom and anti-F(ab')2 antibodies were assessed after three episodes of subcutaneous envenomations with or without treatment with horse F(ab')2. Soluble venom from the Mexican scorpion Centruroides limpidus limpidus was used for these experiments. Repetition of episodes did not induce different mortality rates in untreated mice. F(ab')2 rescued about 85% of the mice in the first two episodes and 66% in the third, without distinction of gender or ostensible side-effects: a suggestion of selection of the most resistant mice. Surviving mice produced in vitro neutralizing antibodies to the scorpion venom and also antibodies to F(ab')2, when injected alone but more so if combined: a possible immunological adjuvant or alarm effect of the venom or of the cascading physiopathology of envenomation. In the few surviving mice, both anti-venom and anti-F(ab')2 antibodies increased significantly after the first envenomation but not thereafter, showing no correlation with mortality rates: a suggestion of their clinical irrelevance, the few hard-to kill mice appeared to resist envenomation by mechanisms other than antibody response. Injection of F(ab')2 alone induced production of detectable anti-venom antibodies in a few mice and injection of venom alone induced that of anti-F(ab')2 antibodies, perhaps due to trace amounts of venom in the high affinity fraction of F(ab')2 and to anti-idiotypic antibodies or polyclonal activity in the envenomation episode, respectively.

  7. Determination of potency and paraspecific effects of Androctonus crassicauda (Olivier, 1807 antivenom against Mesobuthus gibbosus (Brullé, 1832 venom (Scorpiones: Buthidae

    Directory of Open Access Journals (Sweden)

    O. Ozkan

    2007-01-01

    Full Text Available Scorpion envenomation remains a real health problem in many countries. In scorpionism cases, it is often recommended that patients be treated with species-specific antivenom. Androctonus crassicauda venom has been used as antigen for antivenom production in Turkey, where this antivenom, called Turkish antivenom, has also been effective in the treatment of envenomation caused by species other than A. crassicauda. The present study aimed at determining the paraspecific effects and potency of the Turkish antivenom against Mesobuthus gibbosus (Brullé, 1832 venom. To assess the venom toxicity and the antivenom efficacy, we determined the Minimum Lethal Dose (MLD and the Minimum Effective Dose (MED instead of LD50 and ED50, respectively. Androctonus crassicauda antivenom was capable of neutralizing M. gibbosus venom (20 MLD. This was the first study indicating that A. crassicauda antivenom can be used for the treatment of Mesobuthus gibbosus stings, especially in Aegean Region, Turkey.

  8. Scorpion venom heat-resistant peptide (SVHRP) enhances neurogenesis and neurite outgrowth of immature neurons in adult mice by up-regulating brain-derived neurotrophic factor (BDNF).

    Science.gov (United States)

    Wang, Tao; Wang, Shi-Wei; Zhang, Yue; Wu, Xue-Fei; Peng, Yan; Cao, Zhen; Ge, Bi-Ying; Wang, Xi; Wu, Qiong; Lin, Jin-Tao; Zhang, Wan-Qin; Li, Shao; Zhao, Jie

    2014-01-01

    Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM) to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2'-dexoxyuridine (BrdU)-positive cells, BrdU-positive/neuron-specific nuclear protein (NeuN)-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM)-positive immature neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB) in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF) but not nerve growth factor (NGF) or glial cell line-derived neurotrophic factor (GDNF) was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP)-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values of SVHRP.

  9. The dilemma of choosing a reference character for measuring sexual size dimorphism, sexual body component dimorphism, and character scaling: cryptic dimorphism and allometry in the scorpion Hadrurus arizonensis.

    Directory of Open Access Journals (Sweden)

    Gerad A Fox

    Full Text Available Sexual differences in morphology, ranging from subtle to extravagant, occur commonly in many animal species. These differences can encompass overall body size (sexual size dimorphism, SSD or the size and/or shape of specific body parts (sexual body component dimorphism, SBCD. Interacting forces of natural and sexual selection shape much of the expression of dimorphism we see, though non-adaptive processes may be involved. Differential scaling of individual features can result when selection favors either exaggerated (positive allometry or reduced (negative allometry size during growth. Studies of sexual dimorphism and character scaling rely on multivariate models that ideally use an unbiased reference character as an overall measure of body size. We explored several candidate reference characters in a cryptically dimorphic taxon, Hadrurus arizonensis. In this scorpion, essentially every body component among the 16 we examined could be interpreted as dimorphic, but identification of SSD and SBCD depended on which character was used as the reference (prosoma length, prosoma area, total length, principal component 1, or metasoma segment 1 width. Of these characters, discriminant function analysis suggested that metasoma segment 1 width was the most appropriate. The pattern of dimorphism in H. arizonensis mirrored that seen in other more obviously dimorphic scorpions, with static allometry trending towards isometry in most characters. Our findings are consistent with the conclusions of others that fecundity selection likely favors a larger prosoma in female scorpions, whereas sexual selection may favor other body parts being larger in males, especially the metasoma, pectines, and possibly the chela. For this scorpion and probably most other organisms, the choice of reference character profoundly affects interpretations of SSD, SBCD, and allometry. Thus, researchers need to broaden their consideration of an appropriate reference and exercise caution

  10. The dilemma of choosing a reference character for measuring sexual size dimorphism, sexual body component dimorphism, and character scaling: cryptic dimorphism and allometry in the scorpion Hadrurus arizonensis.

    Science.gov (United States)

    Fox, Gerad A; Cooper, Allen M; Hayes, William K

    2015-01-01

    Sexual differences in morphology, ranging from subtle to extravagant, occur commonly in many animal species. These differences can encompass overall body size (sexual size dimorphism, SSD) or the size and/or shape of specific body parts (sexual body component dimorphism, SBCD). Interacting forces of natural and sexual selection shape much of the expression of dimorphism we see, though non-adaptive processes may be involved. Differential scaling of individual features can result when selection favors either exaggerated (positive allometry) or reduced (negative allometry) size during growth. Studies of sexual dimorphism and character scaling rely on multivariate models that ideally use an unbiased reference character as an overall measure of body size. We explored several candidate reference characters in a cryptically dimorphic taxon, Hadrurus arizonensis. In this scorpion, essentially every body component among the 16 we examined could be interpreted as dimorphic, but identification of SSD and SBCD depended on which character was used as the reference (prosoma length, prosoma area, total length, principal component 1, or metasoma segment 1 width). Of these characters, discriminant function analysis suggested that metasoma segment 1 width was the most appropriate. The pattern of dimorphism in H. arizonensis mirrored that seen in other more obviously dimorphic scorpions, with static allometry trending towards isometry in most characters. Our findings are consistent with the conclusions of others that fecundity selection likely favors a larger prosoma in female scorpions, whereas sexual selection may favor other body parts being larger in males, especially the metasoma, pectines, and possibly the chela. For this scorpion and probably most other organisms, the choice of reference character profoundly affects interpretations of SSD, SBCD, and allometry. Thus, researchers need to broaden their consideration of an appropriate reference and exercise caution in interpreting

  11. Scorpion venom heat-resistant peptide (SVHRP enhances neurogenesis and neurite outgrowth of immature neurons in adult mice by up-regulating brain-derived neurotrophic factor (BDNF.

    Directory of Open Access Journals (Sweden)

    Tao Wang

    Full Text Available Scorpion venom heat-resistant peptide (SVHRP is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2'-dexoxyuridine (BrdU-positive cells, BrdU-positive/neuron-specific nuclear protein (NeuN-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM-positive immature neurons in the subventricular zone (SVZ and subgranular zone (SGZ of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF but not nerve growth factor (NGF or glial cell line-derived neurotrophic factor (GDNF was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values

  12. Responsive metal complexes: a click-based "allosteric scorpionate" complex permits the detection of a biological recognition event by EPR/ENDOR spectroscopy.

    Science.gov (United States)

    Tamanini, Emiliano; Rigby, Stephen E J; Motevalli, Majid; Todd, Matthew H; Watkinson, Michael

    2009-01-01

    Chemical sensing is a mature field, and many effective sensors for small anions and cations have been devised. Metal complexes have been used widely for this purpose, but there are fewer reports of their use in the detection of organic and biological analytes. To date metal complexes have been used in sensing via the direct displacement of a pre-existing ligand by an analyte, or by an adventitious complementarity between the complex and analyte. These strategies do not permit a general approach to the sensing of biological molecules with metal complexes because of the demands to engineer molecular recognition into the complex architecture. We describe a fundamentally new approach to this field-the "allosteric scorpionate" metal complex. The binding partner of a biological analyte is attached to a scorpionate ligand on a metal complex, remote from the metal centre. Binding of the analyte causes a change in the primary coordination sphere at the metal, thereby revealing the presence of the biological molecule. We show that azamacrocyclic complexes with a triazole scorpion ligand may be easily assembled with the [3+2] Huisgens 'click' cycloaddition. We demonstrate the synthesis of a biotin-functionalised cyclam derivative using this methodology. This, and our previously communicated zinc sensor, are to the best of our knowledge the first examples of a triazole being employed as a scorpion ligand on an azamacrocycle. Coordination by the triazole to the metal is perturbed by the binding of avidin to the pendant ligand. This event can be sensitively detected with EPR spectroscopy, and the details of the coordination change probed with ENDOR spectroscopy, confirming the loss of the axial triazole nitrogen donor upon binding to avidin. This represents the first metal complex where remote, 'allosteric' coordination of an analyte has been shown to cause a change in the primary coordination sphere of the metal. Since the synthesis is modular and straightforward, other

  13. Una especie nueva de alacrán del género Centruroides de importancia médica (Scorpiones: Buthidae del estado de Guerrero, México A new scorpion species of medical importance of the genus Centruroides (Scorpiones: Buthidae from the state of Guerrero, Mexico

    Directory of Open Access Journals (Sweden)

    José Guadalupe Baldazo-Monsivaiz

    2013-03-01

    Full Text Available Se describe Centruroides villegasi sp. nov. del municipio de Chilapa de Álvarez, Guerrero, que es la novena especie de Centruroides registrada para el estado. Se compara con C. limpidus (Karsch, 1879 por su parecido morfológico y por habitar la misma zona geográfica. Se compara también con C. balsasensis Ponce y Francke, 2004, C. meisei Hoffmann, 1938 y C. tecomanus Hoffmann, 1932, por pertenecer al grupo "alacranes rayados" (sensu Hoffmann, 1932, por su parecido morfológico y por su registro en Guerrero. Es una especie de importancia médica que no se había recolectado o reconocido previamente. Se incluye una lista de las especies de alacranes reconocidas para Guerrero, después de actualizar datos y hacer las correcciones necesarias a los registros históricos para el estado.Centruroides villegasi sp. nov. from the municipality of Chilapa de Álvarez, Guerrero, Mexico is described. It is the nineth species of Centruroides reported for this state. The new species is compared with C. limpidus (Karsch, 1879 which is morphologically similar and inhabits the same geographic zone. The species C. balsasensis Ponce and Francke, 2004, C. meisei Hoffmann, 1938, and C. tecomanus Hoffmann, 1932 are also compared because they are found in Guerrero and belong to the "striped scorpions" group (sensu Hoffmann, 1932, and therefore they are morphologically similar to the new species. It is a species of medical importance that had not been collected or recognized previously. A list of species of scorpions recorded for the state of Guerrero is included after the revision and correction of historical records.

  14. Molecular cloning and biochemical characterization of the first Na(+)-channel α-type toxin peptide (Acra4) from Androctonus crassicauda scorpion venom.

    Science.gov (United States)

    Caliskan, Figen; Quintero-Hernández, Veronica; Restano-Cassulini, Rita; Coronas-Valderrama, Fredy I; Corzo, Gerardo; Possani, Lourival D

    2013-06-01

    Due to the medical importance played in Turkey by stings of the scorpion Androctonus crassicauda, its venom has been studied with more attention. In this communication we report a new toxic peptide, named Acra4, because it is the fourth peptide completely characterized from venom of this scorpion. The peptide contains 64 amino acid residues stabilized by four disulfide bridges, with a molecular weight of 6937 Da. Purification of the lethal peptide was performed by three steps of high performance liquid chromatography (HPLC) separations, and the molecular weight was determined by mass spectrometry analysis and the full amino acid sequence was obtained by direct Edman degradation in conjunction with gene cloning. The LD50 of Acra4 was 50.5 ng/20 g mouse body weight (95% confidence intervals from 48.8 to 52.2 ng/20 g mouse body weight). Additionally, from a sample of cDNA of A. crassicauda four genes were cloned displaying sequence similarities to known scorpion toxins, and are reported here as potentially toxic peptides, named Acra5 to Acra8. Electrophysiological studies of Acra4 were performed using Na(+)-channels expressed in F11 cell culture, by patch-clamp recordings. This is the first time that such peptide from A. crassicauda having a specific Na(+)-channel α-type effect is reported. Its affinity toward Na(+)-channels in F11 cell line is in the order of 1 μM concentration.

  15. Chinese-scorpion (Buthus martensi Karsch) toxin BmK alphaIV, a novel modulator of sodium channels: from genomic organization to functional analysis.

    Science.gov (United States)

    Chai, Zhi-Fang; Zhu, Mang-Mang; Bai, Zhan-Tao; Liu, Tong; Tan, Miao; Pang, Xue-Yan; Ji, Yong-Hua

    2006-11-01

    In the present study, BmK alphaIV, a novel modulator of sodium channels, was cloned from venomous glands of the Chinese scorpion (Buthus martensi Karsch) and expressed successfully in Escherichia coli. The BmK alphaIV gene is composed of two exons separated by a 503 bp intron. The mature polypeptide contains 66 amino acids. BmK alphaIV has potent toxicity in mice and cockroaches. Surface-plasmon-resonance analysis found that BmK alphaIV could bind to both rat cerebrocortical synaptosomes and cockroach neuronal membranes, and shared similar binding sites on sodium channels with classical AaH II (alpha-mammal neurotoxin from the scorpion Androctonus australis Hector), BmK AS (beta-like neurotoxin), BmK IT2 (the depressant insect-selective neurotoxin) and BmK abT (transitional neurotoxin), but not with BmK I (alpha-like neurotoxin). Two-electrode voltage clamp recordings on rNav1.2 channels expressed in Xenopus laevis oocytes revealed that BmK alphaIV increased the peak amplitude and prolonged the inactivation phase of Na+ currents. The structural and pharmacological properties compared with those of other scorpion alpha-toxins suggests that BmK alphaIV represents a novel subgroup or functional hybrid of alpha-toxins and might be an evolutionary intermediate neurotoxin for alpha-toxins.

  16. Purification, characterization and functional expression of a new peptide with an analgesic effect from Chinese scorpion Buthus martensii Karsch (BmK AGP-SYPU1).

    Science.gov (United States)

    Wang, Yu; Wang, Li; Cui, Yong; Song, Yong-Bo; Liu, Yan-Feng; Zhang, Rong; Wu, Chun-Fu; Zhang, Jing-Hai

    2011-07-01

    In this study, a new peptide named BmK AGP-SYPU1 with an analgesic effect was purified from the venom of Chinese scorpion Buthus martensi Karsch (BmK) through a four-step chromatographic process. The mouse twisting test was used to identify the target peptides in every separation step. The purified BmK AGP-SYPU1 was further qualified by RP-HPLC and HPCE. The molecular mass determined by the MALDI-4800-TOF/TOF MS for BmK AGP-SYPU1 was 7544 Da. Its primary structure of the N-terminal was obtained using Edman degradation. The gene sequence of BmK AGP-SYPU1 was cloned from the cDNA pool and genomic of scorpion glands, respectively, and then expressed in Escherichia coli. The sequence determination showed that BmK AGP-SYPU1 was composed of 66 amino acid residues with a new primary structure. The metal chelating affinity column and cation exchange chromatography were used to purify the recombinant BmK AGP-SYPU1. Consequently, the native and recombinant BmK AGP-SYPU1 showed similar analgesic effects on mice as assayed using a mouse twisting model. These results suggested that BmK AGP-SYPU1 is a new analgesic component found in the Chinese scorpion Buthus martensi Karsch.

  17. Morphology of the prosomal endoskeleton of Scorpiones (Arachnida) and a new hypothesis for the evolution of cuticular cephalic endoskeletons in arthropods.

    Science.gov (United States)

    Shultz, Jeffrey W

    2007-03-01

    Skeletomuscular anatomy of the scorpion prosoma is examined in an attempt to explain the evolution of two endoskeletal features, a muscular diaphragm dividing the prosoma and opisthosoma and cuticular epistomal entapophyses with a uniquely complex arrangement of muscles, tendons and ligaments. Both structures appear to be derived from modifications of the mesodermal intersegmental endoskeleton that is primitive for all major arthropod groups. The scorpion diaphragm is a compound structure comprising axial muscles and pericardial ligaments of segments VI to VIII and extrinsic muscles of leg 4 brought into contact by longitudinal reduction of segment VII and integrated into a continuous subvertical sheet. This finding reconciles a long-standing conflict between one interpretation of opisthosomal segmentation based on scorpion embryology and another derived from comparative skeletomuscular anatomy. A new evolutionary-developmental mechanism is proposed to account for the complex morphology of the epistomal entapophyses. Each entapophysis receives 14 muscles and tendons that in other taxa would attach to the anterior connective endoskeleton in the same relative positions. This observation suggests that the embryological precursor to the connective endoskeleton can initiate and guide ectodermal invagination and thereby serve as a spatial template for the development of cuticular apodemes. This mesoderm-template model of ectodermal invagination is potentially applicable to all arthropods and may explain structural diversity and convergence in cephalic apodemes throughout the group. The model is used to interpret the cephalic endoskeletons of two non-chelicerate arthropods, Archaeognatha (Hexapoda) and Symphyla (Myriapoda), to demonstrate the generality of the model.

  18. Biochemical and physiological characterization of a new Na(+)-channel specific peptide from the venom of the Argentinean scorpion Tityus trivittatus.

    Science.gov (United States)

    Coronas, Fredy I V; Diego-García, Elia; Restano-Cassulini, Rita; de Roodt, Adolfo R; Possani, Lourival D

    2015-06-01

    A new peptide with 61 amino acids cross-linked by 4 disulfide bridges, with molecular weight of 6938.12Da, and an amidated C-terminal amino acid residue was purified and characterized. The primary structure was obtained by direct Edman degradation and sequencing its gene. The peptide is lethal to mammals and was shown to be similar (95% identity) to toxin Ts1 (gamma toxin) from the Brazilian scorpion Tityus serrulatus; it was named Tt1g (from T. trivittatus toxin 1 gamma-like). Tt1g was assayed on several sub-types of Na(+)-channels showing displacement of the currents to more negative voltages, being the hNav1.3 the most affected channel. This toxin displays characteristics typical to the β-type sodium scorpion toxins. Lethality tests and physiological assays indicate that this peptide is probably the most important toxic component of this species of scorpion, known for causing human fatalities in the South American continent.

  19. Amino Acid Sequence of an Excitatory Insect-selective Toxin (BmK IT) From Venom of the Scorpion Buthus martensi Karsch

    Institute of Scientific and Technical Information of China (English)

    吉永华; P. Mansuelle; 徐科; C. Granier; C. Kopeyan; S. Terakawa; H. Rochat

    1994-01-01

    The insect-selective neurotoxin(BmK IT) of scorpion Buthus martensi Karsch was first reduced and S-alkylated, and then digested by TPCK-trypsin and Staphylococcus aureus V-8 Protease. The enzymatic peptides were purified on TLC-plastic sheet and submitted to determine their amino acid compositions and sequences. The sequence of the 70 amino acid residues of BmK IT was established with reference to the primary structure of AaH IT, another excitatory insect-selective toxin from the venom of North African scorpion Androctonus australis Hector. About 75% of the homologous sequence was found in the molecules of BmK IT and AaH IT. It is obvious that the results contribute toward better understanding of the molecular structure characteristics, structure/activity relationship of scorpion insect-selective toxins, and they can serve as the molecular basis for utilizing the toxins as a tool to clarify molecular mechanism involved in channel gating, and to infer the possibility of developing them as new selective b

  20. Neutralization of Gating Charges in Domain II of the Sodium Channel α Subunit Enhances Voltage-Sensor Trapping by a β-Scorpion Toxin

    Science.gov (United States)

    Cestèle, Sandrine; Scheuer, Todd; Mantegazza, Massimo; Rochat, Hervé; Catterall, William A.

    2001-01-01

    β-Scorpion toxins shift the voltage dependence of activation of sodium channels to more negative membrane potentials, but only after a strong depolarizing prepulse to fully activate the channels. Their receptor site includes the S3–S4 loop at the extracellular end of the S4 voltage sensor in domain II of the α subunit. Here, we probe the role of gating charges in the IIS4 segment in β-scorpion toxin action by mutagenesis and functional analysis of the resulting mutant sodium channels. Neutralization of the positively charged amino acid residues in the IIS4 segment by mutation to glutamine shifts the voltage dependence of channel activation to more positive membrane potentials and reduces the steepness of voltage-dependent gating, which is consistent with the presumed role of these residues as gating charges. Surprisingly, neutralization of the gating charges at the outer end of the IIS4 segment by the mutations R850Q, R850C, R853Q, and R853C markedly enhances β-scorpion toxin action, whereas mutations R856Q, K859Q, and K862Q have no effect. In contrast to wild-type, the β-scorpion toxin Css IV causes a negative shift of the voltage dependence of activation of mutants R853Q and R853C without a depolarizing prepulse at holding potentials from −80 to −140 mV. Reaction of mutant R853C with 2-aminoethyl methanethiosulfonate causes a positive shift of the voltage dependence of activation and restores the requirement for a depolarizing prepulse for Css IV action. Enhancement of sodium channel activation by Css IV causes large tail currents upon repolarization, indicating slowed deactivation of the IIS4 voltage sensor by the bound toxin. Our results are consistent with a voltage-sensor–trapping model in which the β-scorpion toxin traps the IIS4 voltage sensor in its activated position as it moves outward in response to depolarization and holds it there, slowing its inward movement on deactivation and enhancing subsequent channel activation. Evidently

  1. Pre-clinical studies of toxin-specific Nanobodies: Evidence of in vivo efficacy to prevent fatal disturbances provoked by scorpion envenoming

    Energy Technology Data Exchange (ETDEWEB)

    Hmila, Issam [Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Cosyns, Bernard [Laboratory of In Vivo Cellular and Molecular Imaging, Vrije Universiteit Brussel (Belgium); Tounsi, Hayfa [Service d' Anatomo-Pathologie, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Roosens, Bram; Caveliers, Vicky [Laboratory of In Vivo Cellular and Molecular Imaging, Vrije Universiteit Brussel (Belgium); Abderrazek, Rahma Ben [Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Boubaker, Samir [Service d' Anatomo-Pathologie, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Muyldermans, Serge [Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel (Belgium); Department of Structural Biology, VIB, Brussels (Belgium); El Ayeb, Mohamed [Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Bouhaouala-Zahar, Balkiss, E-mail: balkiss.bouhaouala@pasteur.rns.tn [Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13 Place Pasteur, BP-74, 1002 Tunis (Tunisia); Faculté de Médecine de Tunis, Université de Tunis-El Manar (Tunisia); Lahoutte, Tony [Laboratory of In Vivo Cellular and Molecular Imaging, Vrije Universiteit Brussel (Belgium)

    2012-10-15

    Scorpions represent a significant threat to humans and animals in various countries throughout the world. Recently, we introduced Nanobodies (Nbs) to combat more efficiently scorpion envenoming and demonstrated the performance of NbAahIF12 and NbAahII10 to neutralize scorpion toxins of Androctonus australis hector venom. A bispecific Nb construct (NbF12-10) comprising these two Nbs is far more protective than the classic Fab′{sub 2} based therapy and is the most efficient antivenom therapy against scorpion sting in preclinical studies. Now we investigate the biodistribution and pharmacokinetics of {sup 99m}Tc labeled Nbs by in vivo imaging in rodents and compared these data with those of the Fab′{sub 2} product (PAS). The pharmacodynamics of the Nbs was investigated in rats by in vivo echocardiography and it is shown that NbF12-10 prevents effectively the hemodynamic disturbances induced by a lethal dose of venom. Moreover, even a late injection of NbF12-10 restores the heart rate and brings the blood pressure to baseline values. Histology confirms that NbF12-10 prevents lung and heart lesions of treated mice after envenoming. In conjunction, in this preclinical study, we provide proof of concept that NbF12-10 prevents effectively the fatal disturbances induced by Androctonus venom, and that the Nanobody based therapeutic has a potential to substitute the classic Fab′{sub 2} based product as immunotherapeutic in scorpion envenoming. Further clinical study using larger cohorts of animals should be considered to confirm the full protecting potential of our NbF12-10. -- Highlights: ► Nanobody therapy prevents the hemodynamic disturbances induced by a lethal dose. ► Late injection of Nanobody restores hemodynamic parameters to baseline values. ► Nanobody therapy prevents lung and heart lesions of treated mice after envenoming. ► Labeled Nanobody and Fab’2 pharmacokinetics curves reach plateau in favour of Nanobody.

  2. Characterization of a new Kv1.3 channel-specific blocker, J123, from the scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Shijin, Yin; Hong, Yi; Yibao, Ma; Zongyun, Chen; Han, Song; Yingliang, Wu; Zhijian, Cao; Wenxin, Li

    2008-09-01

    The potassium channel Kv1.3 is an attractive pharmacological target for T-cell-mediated autoimmune diseases, and specific and selective peptidic blockers of Kv1.3 channels have served as valuable therapeutic leads for treating these diseases. Here, we found a new peptide toxin, J123, with 43 amino acids including six cysteine residues by screening the venomous cDNA library of scorpion Buthus martensii Karsch, which has been used as traditional medicine in China for more than 2000 years. The sequence analysis suggested that peptide J123 constituted a new member of the alpha-KTx toxins. The electrophysiological experiments further indicated that peptide J123 has a novel pharmacological profiles: it blocked Kv1.3 channel with high potency (IC50=0.79 nM), and exhibited good selectivity on Kv1.3 over Kv1.1 (>1000-fold) and Kv1.2 (about 30-fold), respectively. Furthermore, peptide J123 had no activity on SKCa2 and SKCa3 channels at micromolar concentration level. Based on the pharmacological activities, the possible channel-interacting surface of peptide J123 was also predicted by molecular modeling and docking. All these data not only enrich the knowledge of the structure-function relationship of the new Kv1.3-speicific peptide but also present a potential drug candidate for selectively targeting Kv1.3 channels.

  3. Scorpion venom activates natural killer cells in hepatocellular carcinoma via the NKG2D-MICA pathway.

    Science.gov (United States)

    Chen, Han; Zhidan, Wang; Xia, Ren; Zhaoxia, Wang; Qing, Jia; Qiang, Guo; Haipeng, Yin; Hengxiao, Wang

    2016-06-01

    Previous studies have demonstrated that polypeptides extracted from scorpion venom (PESV) inhibited cell proliferation in several tumors, however, the effect on dysfunctional and exhausted natural killer cells which contribute to tumor escape from immune surveillance remain to be elucidated. In this study, we determined the effect of PESV on NK infiltration into H22 cells orthotopic transplantation tumors and on the expression of MHC class I chain-related proteins A (MICA) in HepG2 cells. We found that tumor growth in mice was significantly inhibited by PESV and the survival time of tumor-bearing mice treated with PESV was significantly prolonged. Moreover, levels of tumor-infiltrating NK cells, NKG2D protein, perforin and granzyme B mRNA were significantly increased in the group treated with PESV compared with the tumor-bearing control group. In addition, In addition, up-regulation of MICA by PESV enhances the susceptibility of HepG2 cells to NK lysis in vitro. These results indicate that the inhibitory effects of PESV on hepatic carcinoma are likely mediated by up-regulation of NK cell activity via the MICA-NKG2D pathway.

  4. Two new cave-dwelling genera of short-tailed whip-scorpions from Brazil (Arachnida: Schizomida: Hubbardiidae

    Directory of Open Access Journals (Sweden)

    Ricardo Pinto-da-Rocha

    2016-01-01

    Full Text Available ABSTRACT Two new genera of short-tailed whip-scorpions are described based on material from Brazilian iron ore and canga caves in the Carajás region, Pará, Brazil. Naderiore gen. nov. with a single species N. carajas sp. nov. and also monotypic Cangazomus gen. nov. (type species C. xikrin sp. nov.. The relationships of the two new genera with previously described genera are discussed. Naderiore most closely resembles Adisomus Cokendolpher & Reddell, 2000, Piaroa Villarreal, Tourinho & Giupponi, 2008 and Calima Moreno-González & Villarreal, 2012, and can be distinguished from them by Dm3 modified as macrosetae in the male flagellum. Cangazomus most closely resembles Naderiore , Adisomus Cokendolpher & Reddell, 2000, and Piaroa Villarreal, Tourinho & Giupponi, 2008. It differs from all of them by the presence of two pairs of ramified spermathecal lobes, each composed of a differentiated stalk and distoterminal ramified bulbs, chitinized arch without anterior branch and notched lateral tip, pedipalps unarmed and not sexually dimorphic, and the male flagellar setae Dm3 as a microsetae.

  5. Effects of Androctonus crassicauda (Olivier, 1807 (scorpiones: buthidae venom on rats: correlation among acetylcholinesterase activities and electrolytes levels

    Directory of Open Access Journals (Sweden)

    O. Ozkan

    2007-01-01

    Full Text Available Scorpions can be considered living fossils because they have changed so little during the last 400 million years. They are venomous arthropods of the Arachnida class and regarded as relatives of spiders, ticks and mites. The aim of the present study was to evaluate the toxicity of Androctonus crassicauda (Olivier, 1807 venom and its effects on the acetylcholinesterase (AchE activity and on electrolytes levels in rats. Animals were divided into seven groups of five rats each. Test groups received 250µg/kg of venom solution while control group was treated with 200µl of physiological saline solution (PSS. Blood samples were collected from the animals on the 1st, 2nd 4th, 8th, 12th, and 24th hours after subcutaneous injection of venom. Animals were monitored for 24 hours. Androctonus crassicauda venom significantly reduced AchE activity on the 12th hour when compared with control group. A statistically negative correlation between Na+ and K+ (p<0.05 and a positive correlation between Na+ and CL- (p<0.001 ions levels were observed after the administration of A. crassiccauda venom to rats. We can conclude that the differences in the electrolytes levels are due to acute renal failure, since elimination of toxin occurs primarily via the kidney.

  6. Role of lysine and tryptophan residues in the biological activity of toxin VII (Ts gamma) from the scorpion Tityus serrulatus.

    Science.gov (United States)

    Hassani, O; Mansuelle, P; Cestèle, S; Bourdeaux, M; Rochat, H; Sampieri, F

    1999-02-01

    Toxin VII (TsVII), also known as Ts gamma, is the most potent neurotoxin in the venom of the Brazilian scorpion Tityus serrulatus. It has been purified to homogeneity using a new fast and efficient method. Chemical modification of TsVII with the tryptophan-specific reagent o-nitrophenylsulfenyl chloride yielded three modified derivatives (residues Trp39, Trp50 and Trp54). Acetylation of TsVII mostly generated the monoacetylated Lys12 derivative. No side reactions were detected, as indicated by endoproteinase Lys-C peptide mapping, Edman degradation and electrospray mass spectrometry. Circular dichroism and fluorimetric measurements showed that none of the chemical modifications altered the overall structure of the derivatives. The acetylation of Lys12 or the sulfenylation of Trp39 or Trp54 led to a loss of both toxicity in mice and apparent binding affinity for rat brain and cockroach synaptosomal preparations. Sulfenylation of Trp50, however, moderately affected the toxicity of TsVII in mice and had almost no effect on its binding properties. A 3-dimensional model of TsVII was constructed by homology modeling. It suggests that the most reactive residues (Lys12 and Trp39 and Trp54) are all important in the functional disruption of neuronal sodium channels by TsVII, and are close to each other in the hydrophobic conserved region.

  7. [Genomic DNA sequences and functional expression, purification of BmalphaTX14 neurotoxin from scorpion Buthus martensii Karsch].

    Science.gov (United States)

    Lü, Meng; Wang, Kun; Cao, Zhi-Jian; Jiang, Da-He; Mao, Xin; Li, Wen-Xin

    2005-11-01

    Based on the full-length cDNA of BmalphaTX14 from Chinese scorpion Buthus martensii Karsch (BmK), gene of the mature peptide of BmalphaTX14 was cloned into the yeast expression vector pPIC9K. After transforming, screening and inducing, tricine-SDS-PAGE and Western blot proved that rBmalphaTX14 protein was expressed in the medium for up to 84 hours, getting nearly 120 mg/L. Recombinant BmalphaTX14 was purified rapidly and efficiently through Ni-NTA-agarose, polyethylene glycol precipitation and gel filtration chromatography. The purified rBmalphaTX14 proved to have the anti-insect activity by toxicity assay. Meanwhile, genomic gene of BmalphaTX14 was cloned and sequenced by PCR method, sequence analysis of this gene showed that BmalphaTX14 had an intron of 408 base pairs located at the signal peptide encoding region, which was similar with the characteristic of other alpha-type sodium ion-channel toxin. Considering both the genomic organization and the peptide function, BmaTX14 proved to be a membership belonging to alpha-type sodium ion-channel toxin.

  8. Anti-proliferative Effects of Androctonus amoreuxi Scorpion and Cerastes cerastes Snake Venoms on Human Prostate Cancer Cells

    Science.gov (United States)

    Akef, Hassan; Kotb, Nahla; Abo-Elmatty, Dina; Salem, Sayed

    2017-01-01

    The present study evaluated the effects of Androctonus amoreuxi scorpion venom, Cerastes cerastes snake venom and their mixture on prostate cancer cells (PC3). An MTT assay was used to determine the anti-proliferative effect of the venoms, while quantitative real time PCR was used to evaluate the expression of apoptosis-related genes (Bax and Bcl-2). Furthermore, colorimetric assays were used to measure the levels of malondialdehyde (MDA) and antioxidant enzymes. Our results show that the venoms significantly reduced PC3 cell viability in a dose-dependent manner. On the other hand, these venoms significantly decreased Bcl-2 gene expression. Additionally, C. cerastes venom significantly reduced Bax gene expression, while A. amoreuxi venom and a mixture of A. amoreuxi & C. cerastes venoms did not alter Bax expression. Consequently, these venoms significantly increased the Bax/Bcl-2 ratio and the oxidative stress biomarker MDA. Furthermore, these venoms also increased the activity levels of the antioxidant enzymes, catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase. Overall, the venoms have cytotoxic and anti-proliferative effects on PC3 cells. PMID:28382285

  9. Study of severe scorpion envenoming following subcutaneous venom injection into dogs: Hemodynamic and concentration/effect analysis.

    Science.gov (United States)

    Elatrous, Souheil; Ouanes-Besbes, Lamia; Ben Sik-Ali, Habiba; Hamouda, Zineb; BenAbdallah, Saoussen; Tilouche, Nejla; Jalloul, Faten; Fkih-Hassen, Mohamed; Dachraoui, Fahmi; Ouanes, Islem; Abroug, Fekri

    2015-09-15

    To evaluate the dose-effects of Androctonus australis hector (Aah) venom injected subcutaneously on hemodynamics and neurohormonal secretions, 10 anesthetized and ventilated mongrel dogs, were split in two groups (n = 5/group). Subcutaneous injection was done with either 0.2 mg/kg or 0.125 mg/kg of the purified G50 scorpion toxic fraction. Hemodynamic parameters using right heart catheter were recorded and plasma concentrations of catecholamine, troponin, and serum toxic fraction were measured sequentially from baseline to 120 min. We identified the dose of toxic fraction evoking characteristic hemodynamic perturbation of severe envenomation, the time-lapse to envenomation, and the associated plasma level. The injection of 0.125 mg/kg toxic fraction was not associated with significant variations in hemodynamic parameters, whereas the 0.2 mg/kg dose caused envenomation characterized by significant increase in plasma catecholamines, increased pulmonary artery occluded pressure, mean arterial pressure, and systemic vascular resistance (p < 0.05), in association with sustained decline in cardiac output (p < 0.001). Envenomation occurred by the 30th minute, and the corresponding concentration of toxic fraction was 1.14 ng/ml. The current experiment allowed the identification of the sub-lethal dose (0.2 mg/kg) of the toxic fraction of Aah administered by the subcutaneous route. Two parameters with potential clinical relevance were also uncovered: the time-lapse to envenomation and the corresponding concentration of toxic fraction.

  10. Expression of scorpion toxin LqhIT2 increases the virulence of Metarhizium acridum towards Locusta migratoria manilensis.

    Science.gov (United States)

    Peng, Guoxiong; Xia, Yuxian

    2014-11-01

    LqhIT2 is an insect-specific neurotoxin from the venom of scorpion. In this study, the LqhIT2 gene was introduced into the entomopathogenic fungus, Metarhizium acridum. The virulence of the genetically modified strain MaLqhIT2 was then evaluated against locusts (Locusta migratoria manilensis). Compared with the wild-type strain, the median lethal cell density (LC50) for MaLqhIT2 was a 22.6-fold lower, and the median times to death (LT50) for MaLqhIT2 were reduced by 30.3 and 29.6 %, respectively, after topical inoculation and injection. MaLqhIT2 also grew significantly faster in the hemolymph than wild-type strain. There were no significant differences in germination, appressorium formation and sporulation in locust carcasses between the MaLqhIT2 and wild-type strain. These results indicate that LqhIT2 increased the virulence of M. acridum towards locusts by shortening the in vivo infection period, without affecting cuticle penetration or conidia formation in the carcasses. LqhIT2 thus shows considerable potential for increasing fungal virulence against locusts.

  11. Separation and partial characterization of smooth muscle contractile material in the venom of the scorpion Heterometrus bengalensis.

    Science.gov (United States)

    Kar, P K; Sarangi, B; Datta, A; Gomes, A; Lahiri, S C

    1983-01-01

    A smooth muscle contractile material was separated from crude venom of the scorpion Heterometrus bengalensis (found in Eastern India) by solvent extraction, gel filtration and thin layer chromatography. Smooth muscle contractile material could be extracted, in descending order of efficiency, with methanol, butanol, ethanol and acetone. The contractile material separated by gel filtration (Sephadex G-25) when further extracted, using the Folch procedure, showed a single spot in thin layer chromatography with one solvent system. Rechromatography of an eluate from this spot with another solvent system resolved it into three spots (SL1, SL2 and SL3, the mixture being designated as Substance L) which could be visualized either with iodine vapour, ninhydrin or molybdenum reagent. Eluates from the three spots contracted guinea-pig ileum which had been pretreated with antagonists of ACh, histamine, 5-HT and prostaglandins. Substance L and its fractions (SL1, SL2 and SL3) contain inorganic phosphorus, amino nitrogen and amino sugar, which point to the likelihood of their being glycophosphatides.

  12. The Scorpion Toxin Analogue BmKTX-D33H as a Potential Kv1.3 Channel-Selective Immunomodulator for Autoimmune Diseases

    Directory of Open Access Journals (Sweden)

    Fang Ye

    2016-04-01

    Full Text Available The Kv1.3 channel-acting scorpion toxins usually adopt the conserved anti-parallel β-sheet domain as the binding interface, but it remains challenging to discover some highly selective Kv1.3 channel-acting toxins. In this work, we investigated the pharmacological profile of the Kv1.3 channel-acting BmKTX-D33H, a structural analogue of the BmKTX scorpion toxin. Interestingly, BmKTX-D33H, with its conserved anti-parallel β-sheet domain as a Kv1.3 channel-interacting interface, exhibited more than 1000-fold selectivity towards the Kv1.3 channel as compared to other K+ channels (including Kv1.1, Kv1.2, Kv1.7, Kv11.1, KCa2.2, KCa2.3, and KCa3.1. As expected, BmKTX-D33H was found to inhibit the cytokine production and proliferation of both Jurkat cells and human T cells in vitro. It also significantly improved the delayed-type hypersensitivity (DTH responses, an autoreactive T cell-mediated inflammation in rats. Amino acid sequence alignment and structural analysis strongly suggest that the “evolutionary” Gly11 residue of BmKTX-D33H interacts with the turret domain of Kv1 channels; it appears to be a pivotal amino acid residue with regard to the selectivity of BmKTX-D33H towards the Kv1.3 channel (in comparison with the highly homologous scorpion toxins. Together, our data indicate that BmKTX-D33H is a Kv1.3 channel–specific blocker. Finally, the remarkable selectivity of BmKTX-D33H highlights the great potential of evolutionary-guided peptide drug design in future studies.

  13. Antimicrobial/cytolytic peptides from the venom of the North African scorpion, Androctonus amoreuxi: biochemical and functional characterization of natural peptides and a single site-substituted analog.

    Science.gov (United States)

    Almaaytah, Ammar; Zhou, Mei; Wang, Lei; Chen, Tianbao; Walker, Brian; Shaw, Chris

    2012-06-01

    The venoms of scorpions are complex cocktails of polypeptide toxins that fall into two structural categories: those that contain cysteinyl residues with associated disulfide bridges and those that do not. As the majority of lethal toxins acting upon ion channels fall into the first category, most research has been focused there. Here we report the identification and structural characterization of two novel 18-mer antimicrobial peptides from the venom of the North African scorpion, Androctonus amoreuxi. Named AamAP1 and AamAP2, both peptides are C-terminally amidated and differ in primary structure at just two sites: Leu-->Pro at position 2 and Phe-->Ile at position 17. Synthetic replicates of both peptides exhibited a broad-spectrum of antimicrobial activity against a Gram-positive bacterium (Staphylococcus aureus), a Gram-negative bacterium (Escherichia coli) and a yeast (Candida albicans), at concentrations ranging between 20 μM and 150 μM. In this concentration range, both peptides produced significant degrees of hemolysis. A synthetic replicate of AamAP1 containing a single substitution (His-->Lys) at position 8, generated a peptide (AamAP-S1) with enhanced antimicrobial potency (3-5 μM) against the three test organisms and within this concentration range, hemolytic effects were negligible. In addition, this His-->Lys variant exhibited potent growth inhibitory activity (ID(50) 25-40 μm) against several human cancer cell lines and endothelial cells that was absent in both natural peptides. Natural bioactive peptide libraries, such as those that occur in scorpion venoms, thus constitute a unique source of novel lead compounds with drug development potential whose biological properties can be readily manipulated by simple synthetic chemical means.

  14. Variability of Potassium Channel Blockers in Mesobuthus eupeus Scorpion Venom with Focus on Kv1.1: AN INTEGRATED TRANSCRIPTOMIC AND PROTEOMIC STUDY.

    Science.gov (United States)

    Kuzmenkov, Alexey I; Vassilevski, Alexander A; Kudryashova, Kseniya S; Nekrasova, Oksana V; Peigneur, Steve; Tytgat, Jan; Feofanov, Alexey V; Kirpichnikov, Mikhail P; Grishin, Eugene V

    2015-05-08

    The lesser Asian scorpion Mesobuthus eupeus (Buthidae) is one of the most widely spread and dispersed species of the Mesobuthus genus, and its venom is actively studied. Nevertheless, a considerable amount of active compounds is still under-investigated due to the high complexity of this venom. Here, we report a comprehensive analysis of putative potassium channel toxins (KTxs) from the cDNA library of M. eupeus venom glands, and we compare the deduced KTx structures with peptides purified from the venom. For the transcriptome analysis, we used conventional tools as well as a search for structural motifs characteristic of scorpion venom components in the form of regular expressions. We found 59 candidate KTxs distributed in 30 subfamilies and presenting the cysteine-stabilized α/β and inhibitor cystine knot types of fold. M. eupeus venom was then separated to individual components by multistage chromatography. A facile fluorescent system based on the expression of the KcsA-Kv1.1 hybrid channels in Escherichia coli and utilization of a labeled scorpion toxin was elaborated and applied to follow Kv1.1 pore binding activity during venom separation. As a result, eight high affinity Kv1.1 channel blockers were identified, including five novel peptides, which extend the panel of potential pharmacologically important Kv1 ligands. Activity of the new peptides against rat Kv1.1 channel was confirmed (IC50 in the range of 1-780 nm) by the two-electrode voltage clamp technique using a standard Xenopus oocyte system. Our integrated approach is of general utility and efficiency to mine natural venoms for KTxs.

  15. Mapping the Interaction Site for a β-Scorpion Toxin in the Pore Module of Domain III of Voltage-gated Na+ Channels*

    Science.gov (United States)

    Zhang, Joel Z.; Yarov-Yarovoy, Vladimir; Scheuer, Todd; Karbat, Izhar; Cohen, Lior; Gordon, Dalia; Gurevitz, Michael; Catterall, William A.

    2012-01-01

    Activation of voltage-gated sodium (Nav) channels initiates and propagates action potentials in electrically excitable cells. β-Scorpion toxins, including toxin IV from Centruroides suffusus suffusus (CssIV), enhance activation of NaV channels. CssIV stabilizes the voltage sensor in domain II in its activated state via a voltage-sensor trapping mechanism. Amino acid residues required for the action of CssIV have been identified in the S1-S2 and S3-S4 extracellular loops of domain II. The extracellular loops of domain III are also involved in toxin action, but individual amino acid residues have not been identified. We used site-directed mutagenesis and voltage clamp recording to investigate amino acid residues of domain III that are involved in CssIV action. In the IIISS2-S6 loop, five substitutions at four positions altered voltage-sensor trapping by CssIVE15A. Three substitutions (E1438A, D1445A, and D1445Y) markedly decreased voltage-sensor trapping, whereas the other two substitutions (N1436G and L1439A) increased voltage-sensor trapping. These bidirectional effects suggest that residues in IIISS2-S6 make both positive and negative interactions with CssIV. N1436G enhanced voltage-sensor trapping via increased binding affinity to the resting state, whereas L1439A increased voltage-sensor trapping efficacy. Based on these results, a three-dimensional model of the toxin-channel interaction was developed using the Rosetta modeling method. These data provide additional molecular insight into the voltage-sensor trapping mechanism of toxin action and define a three-point interaction site for β-scorpion toxins on NaV channels. Binding of α- and β-scorpion toxins to two distinct, pseudo-symmetrically organized receptor sites on NaV channels acts synergistically to modify channel gating and paralyze prey. PMID:22761417

  16. Reconstitution of high-affinity binding of a beta-scorpion toxin to neurotoxin receptor site 4 on purified sodium channels.

    Science.gov (United States)

    Thomsen, W; Martin-Eauclaire, M F; Rochat, H; Catterall, W A

    1995-09-01

    Reconstitution of purified sodium channels into phospholipid vesicles restores many aspects of sodium channel function including high-affinity neurotoxin binding and action at neurotoxin receptor sites 1-3 and 5, but neurotoxin binding and action at receptor site 4 has not previously been demonstrated in purified and reconstituted preparations. Toxin IV from the venom of the American scorpion Centruroides suffusus suffusus (Css IV), a beta-scorpion toxin, shifts the voltage dependence of sodium channel activation by binding with high affinity to neurotoxin receptor site 4. Sodium channels were purified from rat brain and reconstituted into phospholipid vesicles composed of phosphatidylcholine and phosphatidylethanolamine (65:35). 125I-Css IV, purified by reversed-phase HPLC, bound rapidly and specifically to reconstituted sodium channels. Dissociation of the bound toxin was biphasic with half-times of 0.22 min-1 and 0.015 min-1. At equilibrium, the toxin bound to two classes of specific high-affinity sites, a variable minor class with KD of approximately 0.1 nM and a major class with a KD of approximately 5 nM. Approximately 0.8 mol 125I-Css IV was bound per mole of reconstituted, right-side-out sodium channels, as assessed from comparison of binding of saxitoxin and Css IV. Binding of Css IV was unaffected by membrane potential or by neurotoxins that bind at sites 1-3 or 5, consistent with the characteristics of binding of beta-scorpion toxins to sodium channels in cells and membrane preparations.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Mapping the interaction site for a β-scorpion toxin in the pore module of domain III of voltage-gated Na(+) channels.

    Science.gov (United States)

    Zhang, Joel Z; Yarov-Yarovoy, Vladimir; Scheuer, Todd; Karbat, Izhar; Cohen, Lior; Gordon, Dalia; Gurevitz, Michael; Catterall, William A

    2012-08-31

    Activation of voltage-gated sodium (Na(v)) channels initiates and propagates action potentials in electrically excitable cells. β-Scorpion toxins, including toxin IV from Centruroides suffusus suffusus (CssIV), enhance activation of Na(V) channels. CssIV stabilizes the voltage sensor in domain II in its activated state via a voltage-sensor trapping mechanism. Amino acid residues required for the action of CssIV have been identified in the S1-S2 and S3-S4 extracellular loops of domain II. The extracellular loops of domain III are also involved in toxin action, but individual amino acid residues have not been identified. We used site-directed mutagenesis and voltage clamp recording to investigate amino acid residues of domain III that are involved in CssIV action. In the IIISS2-S6 loop, five substitutions at four positions altered voltage-sensor trapping by CssIV(E15A). Three substitutions (E1438A, D1445A, and D1445Y) markedly decreased voltage-sensor trapping, whereas the other two substitutions (N1436G and L1439A) increased voltage-sensor trapping. These bidirectional effects suggest that residues in IIISS2-S6 make both positive and negative interactions with CssIV. N1436G enhanced voltage-sensor trapping via increased binding affinity to the resting state, whereas L1439A increased voltage-sensor trapping efficacy. Based on these results, a three-dimensional model of the toxin-channel interaction was developed using the Rosetta modeling method. These data provide additional molecular insight into the voltage-sensor trapping mechanism of toxin action and define a three-point interaction site for β-scorpion toxins on Na(V) channels. Binding of α- and β-scorpion toxins to two distinct, pseudo-symmetrically organized receptor sites on Na(V) channels acts synergistically to modify channel gating and paralyze prey.

  18. The scorpion toxin Amm VIII induces pain hypersensitivity through gain-of-function of TTX-sensitive Na⁺ channels.

    Science.gov (United States)

    Abbas, Najwa; Gaudioso-Tyzra, Christelle; Bonnet, Caroline; Gabriac, Mélanie; Amsalem, Muriel; Lonigro, Aurélie; Padilla, Françoise; Crest, Marcel; Martin-Eauclaire, Marie-France; Delmas, Patrick

    2013-08-01

    Voltage-gated Na(+) channels (Nav) are the targets of a variety of scorpion toxins. Here, we investigated the effects of Amm VIII, a toxin isolated from the venom of the scorpion Androctonus mauretanicus mauretanicus, on pain-related behaviours in mice. The effects of Amm VIII were compared with the classic scorpion α-toxin AaH II from Androctonus australis. Contrary to AaH II, intraplantar injection of Amm VIII at relatively high concentrations caused little nocifensive behaviours. However, Amm VIII induced rapid mechanical and thermal pain hypersensitivities. We evaluated the toxins' effects on Nav currents in nociceptive dorsal root ganglion (DRG) neurons and immortalized DRG neuron-derived F11 cells. Amm VIII and AaH II enhanced tetrodotoxin-sensitive (TTX-S) Nav currents in DRG and F11 cells. Both toxins impaired fast inactivation and negatively shifted activation. AaH II was more potent than Amm VIII at modulating TTX-S Nav currents with EC50 of 5 nM and 1 μM, respectively. AaH II and Amm VIII also impaired fast inactivation of Nav1.7, with EC50 of 6.8 nM and 1.76 μM, respectively. Neither Nav1.8 nor Nav1.9 was affected by the toxins. AaH II and Amm VIII reduced first spike latency and lowered action potential threshold. Amm VIII was less efficient than AaH II in increasing the gain of the firing frequency-stimulation relationship. In conclusion, our data show that Amm VIII, although less potent than AaH II, acts as a gating-modifier peptide reminiscent of classic α-toxins, and suggest that its hyperalgesic effects can be ascribed to gain-of-function of TTX-S Na(+) channels in nociceptors. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  19. Involvement of Cholinergic and Adrenergic Receptors in Pathogenesis and Inflammatory Response Induced by Alpha-Neurotoxin Bot III of Scorpion Venom.

    Science.gov (United States)

    Nakib, Imene; Martin-Eauclaire, Marie-France; Laraba-Djebari, Fatima

    2016-10-01

    Bot III neurotoxin is the most lethal α neurotoxin purified from Buthus occitanus tunetanus scorpion venom. This toxin binds to the voltage-gated sodium channel of excitable cells and blocks its inactivation, inducing an increased release of neurotransmitters (acetylcholine and catecholamines). This study aims to elucidate the involvement of cholinergic and adrenergic receptors in pathogenesis and inflammatory response triggered by this toxin. Injection of Bot III to animals induces an increase of peroxidase activities, an imbalance of oxidative status, tissue damages in lung parenchyma, and myocardium correlated with metabolic disorders. The pretreatment with nicotine (nicotinic receptor agonist) or atropine (muscarinic receptor antagonist) protected the animals from almost all disorders caused by Bot III toxin, especially the immunological alterations. Bisoprolol administration (selective β1 adrenergic receptor antagonist) was also efficient in the protection of animals, mainly on tissue damage. Propranolol (non-selective adrenergic receptor antagonist) showed less effect. These results suggest that both cholinergic and adrenergic receptors are activated in the cardiopulmonary manifestations induced by Bot III. Indeed, the muscarinic receptor appears to be more involved than the nicotinic one, and the β1 adrenergic receptor seems to dominate the β2 receptor. These results showed also that the activation of nicotinic receptor leads to a significant protection of animals against Bot III toxin effect. These findings supply a supplementary data leading to better understanding of the mechanism triggered by scorpionic neurotoxins and suggest the use of drugs targeting these receptors, especially the nicotinic one in order to counteract the inflammatory response observed in scorpion envenomation.

  20. The Scorpion Toxin Analogue BmKTX-D33H as a Potential Kv1.3 Channel-Selective Immunomodulator for Autoimmune Diseases.

    Science.gov (United States)

    Ye, Fang; Hu, Youtian; Yu, Weiwei; Xie, Zili; Hu, Jun; Cao, Zhijian; Li, Wenxin; Wu, Yingliang

    2016-04-19

    The Kv1.3 channel-acting scorpion toxins usually adopt the conserved anti-parallel β-sheet domain as the binding interface, but it remains challenging to discover some highly selective Kv1.3 channel-acting toxins. In this work, we investigated the pharmacological profile of the Kv1.3 channel-acting BmKTX-D33H, a structural analogue of the BmKTX scorpion toxin. Interestingly, BmKTX-D33H, with its conserved anti-parallel β-sheet domain as a Kv1.3 channel-interacting interface, exhibited more than 1000-fold selectivity towards the Kv1.3 channel as compared to other K⁺ channels (including Kv1.1, Kv1.2, Kv1.7, Kv11.1, KCa2.2, KCa2.3, and KCa3.1). As expected, BmKTX-D33H was found to inhibit the cytokine production and proliferation of both Jurkat cells and human T cells in vitro. It also significantly improved the delayed-type hypersensitivity (DTH) responses, an autoreactive T cell-mediated inflammation in rats. Amino acid sequence alignment and structural analysis strongly suggest that the "evolutionary" Gly11 residue of BmKTX-D33H interacts with the turret domain of Kv1 channels; it appears to be a pivotal amino acid residue with regard to the selectivity of BmKTX-D33H towards the Kv1.3 channel (in comparison with the highly homologous scorpion toxins). Together, our data indicate that BmKTX-D33H is a Kv1.3 channel-specific blocker. Finally, the remarkable selectivity of BmKTX-D33H highlights the great potential of evolutionary-guided peptide drug design in future studies.

  1. Activity of scorpion venom-derived antifungal peptides against planktonic cells of Candida spp and Cryptococcus neoformans and Candida albicans biofilms.

    Directory of Open Access Journals (Sweden)

    Fernanda Guilhelmelli

    2016-11-01

    Full Text Available The incidence of fungal infections has been increasing in the last decades, while the number of available antifungal classes remains the same. The natural and acquired resistance of some fungal species to available therapies, associated with the high toxicity of these drugs on the present scenario and makes an imperative of the search for new, more efficient and less toxic therapeutic choices. Antimicrobial peptides (AMPs are a potential class of antimicrobial drugs consisting of evolutionarily conserved multifunctional molecules with both microbicidal and immunomodulatory properties being part of the innate immune response of diverse organisms. In this study, we evaluated 11 scorpion-venom derived non-disulfide-bridged peptides against Cryptococcus neoformans and Candida spp, which are important human pathogens. Seven of them, including two novel molecules, showed activity against both genera with MICs values ranging from 3.12 to 200 µM and an analogous activity against C. albicans biofilms. Most of the peptides presented low hemolytic and cytotoxic activity against mammalian cells. Modifications in the primary peptide sequence, as revealed by in silico and circular dichroism analyses of the most promising peptides, underscored the importance of cationicity for their antimicrobial activity as well the amphipathicity of these molecules and their tendency to form alpha helices. This is the first report of scorpion-derived AMPs against C. neoformans and our results underline the potential of scorpion venom as a source of antimicrobials. Further characterization of their mechanism of action, followed by molecular optimization to decrease their citotoxicity and increase antimicrobial activity, is needed to fully clarify their real potential as antifungals.

  2. MeuTXKbeta1, a scorpion venom-derived two-domain potassium channel toxin-like peptide with cytolytic activity.

    Science.gov (United States)

    Zhu, Shunyi; Gao, Bin; Aumelas, André; del Carmen Rodríguez, Maria; Lanz-Mendoza, Humberto; Peigneur, Steve; Diego-Garcia, Elia; Martin-Eauclaire, Marie-France; Tytgat, Jan; Possani, Lourival D

    2010-04-01

    Recent studies have demonstrated that scorpion venom contains unique two-domain peptides with the peculiarity of possessing different functions, i.e. neurotoxic and cytolytic activities. Here we report systematic characterization of a new two-domain peptide (named MeuTXKbeta1) belonging to the TsTXKbeta molecular subfamily from the scorpion Mesobuthus eupeus by molecular cloning, biochemical purification, recombinant expression, functional assays, CD and NMR studies. Its full-length bioactive form as well as 1-21 and 22-72 fragments (named N(1-21) and C(22-72), respectively) was produced in Escherichia coli by an on-column refolding approach. Recombinant peptide (rMeuTXKbeta1) exhibited a low affinity for K(+) channels and cytolytic effects against bacteria and several eukaryotic cells. N(1-21) was found to preserve anti-Plasmodium activity in contrast to haemolytic activity, whereas C(22-72) retains these two activities. Circular dichroism analysis demonstrates that rMeuTXKbeta1 presents a typical scorpion toxin scaffold in water and its alpha-helical content largely increases in a membrane-mimicking environment, consistent with the NMR structure of N(1-21) and an ab initio structure model of MeuTXKbeta1 predicted using I-TASSER algorithm. Our structural and functional data clearly indicate an evolutionary link between TsTXKbeta-related peptides and antiparasitic scorpines which both comprise the betaSPN (beta-KTxs and scorpines) family. Copyright 2009 Elsevier B.V. All rights reserved.

  3. 抗昆虫蝎毒素多肽的重组表达研究%Recombinant Expression of Anti-insect Scorpion Toxin Peptides

    Institute of Scientific and Technical Information of China (English)

    韩玉莹; 刘霞; 白占涛

    2016-01-01

    Scorpion toxin peptides are strong means of defense and getting food for itself. Anti-insect scorpion toxin peptides target on and regulate gating dynamics of multiple ion channels. It was a kind of potential biopesticide and was of Value in research. Sequence analysis showed that the anti-insect toxin peptides performed about 67% se-quence homology and three dimensional topology all combined by six conserVatiVe scaffold cysteine residues,which may be corresponding to their anti-insect function. NeVertheless,it was difficult to extract natural scorpion toxin peptide that resulted in its research limit of structure and function. Thus the gene recombinant and mutation of high-purity and high-actiVity peptides would be the more effectiVe pathways to elucidate the conserVation and actiVe properties. The paper reViews the current recombination progressing and application of anti-insect scorpion toxin peptides to further our understanding to its structure and anti-insect mechanism.%蝎毒素是蝎子自我防御和捕食的有力工具,属于活性短肽。抗昆虫蝎毒素多肽作用于昆虫细胞膜离子通道,调控通道动力学特性,是潜在的生物杀虫剂,具很高的研究价值。序列比对分析发现,抗昆虫蝎毒素多肽有高保守性,序列同源性达67%,其中有4个保守的半胱氨酸残基,这可能与其抗昆虫作用的结构有关。但天然蝎毒素蛋白获取较困难,致使抗昆虫毒素多肽的结构与功能研究受限,因此,利用基因重组技术获得高纯度高活性重组蝎毒素是有效途径之一。本文综述了抗昆虫蝎毒素多肽外源重组表达的研究现状,旨在更深入全面理解其结构及抗昆虫机理等,以助推后续相关研究。

  4. Purification, amino-acid sequence and partial characterization of two toxins with anti-insect activity from the venom of the South American scorpion Tityus bahiensis (Buthidae).

    OpenAIRE

    2001-01-01

    We report here the isolation by a two-step chromatographic procedure of two new toxins from the South American scorpion Tityus bahiensis. Their amino-acid sequences and some of their biological features were established. The two toxins have different biological properties. Toxin TbIT-I had almost no activity or pharmacological effects in vertebrate tissues whereas it was lethal to house ¯ies (LD50 80.0 ng/house ¯y). In contrast, Tb2-II was active against both mammals (intracerebroventricular ...

  5. Miniaturization of Scorpion β-Toxins Uncovers a Putative Ancestral Surface of Interaction with Voltage-gated Sodium Channels*♦

    OpenAIRE

    2008-01-01

    The bioactive surface of scorpion β-toxins that interact with receptor site-4 at voltage-gated sodium channels is constituted of residues of the conserved βαββ core and the C-tail. In an attempt to evaluate the extent by which residues of the toxin core contribute to bioactivity, the anti-insect and anti-mammalian β-toxins Bj-xtrIT and Css4 were truncated at their N and C termini, resulting in miniature peptides composed essentially of the core secondary structure motives. The truncated β-tox...

  6. Site-directed mutagenesis of the toxin from the Chinese scorpion Buthus martensii Karsch (BmKAS): insight into sites related to analgesic activity.

    Science.gov (United States)

    Cui, Yong; Song, Yong-Bo; Ma, Lin; Liu, Yan-Feng; Li, Guo-Dong; Wu, Chun-Fu; Zhang, Jing-Hai

    2010-10-01

    This study utilized the E. coli expression system to investigate the role of amino acid residues in toxin from the Chinese scorpion--Buthus martensii Karsch (BmKAS). To evaluate the extent to which residues of the toxin core contribute to its analgesic activity, ten mutants of BmKAS were obtained by PCR. Using site-directed mutagenesis, all of these residues were substituted with different amino acids. This study represents a thorough mapping and elucidation of the epitopes that form the molecular basis of the toxin's analgesic activity. Our results showed large mutant-dependent differences that emphasize the important roles of the studied residues.

  7. Cloning and molecular characterization of BmHYA1, a novel hyaluronidase from the venom of Chinese red scorpion Buthus martensi Karsch.

    Science.gov (United States)

    Feng, Luo; Gao, Rong; Meng, Jun; Gopalakrishnakone, Ponnampalam

    2010-09-01

    In this communication, the full protein sequence of a novel venom hyaluronidase BmHYA1 was reported. It is the first full hyaluronidase amino acid sequence from scorpion venom. It was deduced from nucleotide sequence by 3' Rapid Amplification of cDNA Ends (RACE) PCR cloning, followed by alignment with the N-terminal amino acid sequence, which was obtained by Edman degradation. BmHYA1 has 385 amino acid residues containing five potential N-glycosylation sites. The phylogenetic analysis indicates early divergence and independent evolution of BmHYA1 from other hyaluronidases.

  8. Structural Basis of Neutralization of the Major Toxic Component from the Scorpion Centruroides noxius Hoffmann by a Human-derived Single-chain Antibody Fragment*

    OpenAIRE

    Canul-Tec, Juan Carlos; Riaño-Umbarila, Lidia; Rudiño-Piñera, Enrique; Becerril, Baltazar; Possani, Lourival D.; Torres-Larios, Alfredo

    2011-01-01

    It has previously been reported that several single-chain antibody fragments of human origin (scFv) neutralize the effects of two different scorpion venoms through interactions with the primary toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2). Here we present the crystal structure of the complex formed between one scFv (9004G) and the Cn2 toxin, determined in two crystal forms at 2.5 and 1.9 Å resolution. A 15-residue span of the toxin is recognized by th...

  9. NMR solution structure of Cn12, a novel peptide from the Mexican scorpion Centruroides noxius with a typical beta-toxin sequence but with alpha-like physiological activity.

    Science.gov (United States)

    del Río-Portilla, Federico; Hernández-Marín, Elizabeth; Pimienta, Genaro; Coronas, Fredy V; Zamudio, Fernando Z; Rodríguez de la Vega, Ricardo C; Wanke, Enzo; Possani, Lourival D

    2004-06-01

    Cn12 isolated from the venom of the scorpion Centruroides noxius has 67 amino-acid residues, closely packed with four disulfide bridges. Its primary structure and disulfide bridges were determined. Cn12 is not lethal to mammals and arthropods in vivo at doses up to 100 microg per animal. Its 3D structure was determined by proton NMR using 850 distance constraints, 36 phi angles derived from 36 coupling constants obtained by two different methods, and 22 hydrogen bonds. The overall structure has a two and half turn alpha-helix (residues 24-32), three strands of antiparallel beta-sheet (residues 2-4, 37-40 and 45-48), and a type II turn (residues 41-44). The amino-acid sequence of Cn12 resembles the beta scorpion toxin class, although patch-clamp experiments showed the induction of supplementary slow inactivation of Na(+) channels in F-11 cells (mouse neuroblastoma N18TG-2 x rat DRG2), which means that it behaves more like an alpha scorpion toxin. This behaviour prompted us to analyse Na(+) channel binding sites using information from 112 Na(+) channel gene clones available in the literature, focusing on the extracytoplasmic loops of the S5-S6 transmembrane segments of domain I and the S3-S4 segments of domain IV, sites considered to be responsible for binding alpha scorpion toxins.

  10. Scorpion ethanol extract and valproic acid effects on hippocampal glial fibrillary acidic protein expression in a rat model of chronic-kindling epilepsy induced by lithium chloride-pilocarpine

    Institute of Scientific and Technical Information of China (English)

    Yi Liang; Hongbin Sun; Liang Yu; Baoming He; Yan Xie

    2012-01-01

    The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Results were subsequently compared with valproic acid. Results showed gradually-increased hippocampal glial fibrillary acidic protein expression following model establishment; glial fibrillary acidic protein mRNA expression was significantly increased at 3 days, reached a peak at 7 days, and then gradually decreased thereafter. Ethanol extracts of scorpion doses of 580 and 1 160 mg/kg, as well as 120 mg/kg valproic acid, led to a decreased number of glial fibrillary acidic protein-positive cells and glial fibrillary acidic protein mRNA expression, as well as decreased seizure grades and frequency of spontaneously recurrent seizures. The effects of 1 160 mg/kg ethanol extracts of scorpion were equal to those of 120 mg/kg valproic acid. These results suggested that the anti-epileptic effect of ethanol extracts of scorpion were associated with decreased hippocampal glial fibrillary acidic protein expression in a rat model of lithium chloride-pilocarpine induced epilepsy.

  11. 北京地区蝎蛰伤的流行病学特点及中西医结合急诊处置%The epidemic characteristics of scorpion envenomation and emergency treatment by integrated medicine in Beijing

    Institute of Scientific and Technical Information of China (English)

    门保忠; 赵晓东; 苏琴; 张宪; 党伟; 王曼

    2014-01-01

    Objective To investigate the epidemic characteristics of scorpion envenomation in Beijing area, and to provide a new method to manage scorpion envenomation in emergency. Methods 325 cases of scorpion stings from 2005 to 2012 in our department were divided into three groups(mild,medium and severe) according to clinical symptoms and were analyzed statistically, and generalized the law of scorpion activity according to seasons and of clinical manifestations as well as emergency management by integrated medicine. Results The seasons of summer and autumn were the more frequent incidence seasons of scorpion envenomation than other two seasons (P=0.058), geographical distribution concentrates in mountain rural area and bungalow in urban area, and satisfied results were obtained by integrated medicine without antivenom serum treatment. The recovery time among the three groups were different significantly (P=0.0001). Conclusion It is essential to prevent scorpion stings in summer and autumn, and it is a new way to mange scorpion envenomation by integrated medicine without antivenom serum.%目的:探讨北京地区蝎子蛰伤的流行病学特点,为急诊处置蝎蛰伤提供新的正规治疗方法。方法将急诊科2005~2012年325例的蝎蛰伤资料按症状分为轻、中和重度三组进行统计学分析,总结出蝎子活动的季节规律;总结蝎蛰伤的临床表现和中西医结合急诊处置方法。结果夏秋季是北京地区蝎蛰伤多发季节(P=0.058),不用抗毒血清的中西医结合治疗能取得良好的疗效。地理分布多在山区农村和城区的平房区,不同组别的症状消失时间差异有统计学意义(P=0.0001)。结论北京地区夏秋季是防治蝎蛰伤的重要时期;不采用血清疗法,中西医结合不失为一种新的治疗蝎蛰伤有效方法。

  12. 不同地域东亚钳蝎蝎毒的双向电泳鉴定%Identification of Scorpion Venom in Buthus Martensii Karsch from Different Regions by Two-dimensional Gel Electrophoresis (2-DE)

    Institute of Scientific and Technical Information of China (English)

    倪伊婷; 郭美华; 王君德; 刘赟; 辛毅; 吴大畅

    2012-01-01

    Objective To identify qualitatively and analyze the activity of scorpion venom in Buthus Martensii Karsch from different regions by two-dimensional gel electrophoresis (2-DE),and investigate the protein composition and function differences of scorpion venom. Methods Quantitive identification and content determination of proteins in scorpion venom were performed following preconditions including dissolution, desalting and condensing of the freeze-drying scorpion venom powder. The proteins in scorpion venom were separated by pH gradient isoeleciric focusing and SUS-PAGE gel eledrophoresis. The two-dimensional electrophoresis gel map was captured via gel imaging system after staining. The special different proteins were determined and comparatively analyzed through PD Quesl. Image analysis software,and thus the scorpion venom from different regions was qualitatively identified. Results Protein fingerprints were acquired from three samples. Total protein spots were 80,69,77,and the distinctive number of which were 56,46,55 , successively. Conclusion Scorpion venom in Buthus Martensii Karsch from diffe.re.nt regions separated with 2-DE show obviously diverse protein distributions.%目的 利用蛋白质组学中双向电泳技术,定性鉴定、分析不同地域东亚钳蝎蝎毒活性的差别,探索不同产地蝎毒的蛋白质组成及功能差异.方法 将不同产地的冷冻干燥蝎毒粉经溶解、除盐、浓缩后测定蝎毒蛋白质含量,进行定量的蝎毒鉴定.采用pH梯度等电聚焦和SDS-PAGE凝胶电泳技术分离蝎毒蛋白质.银染后通过凝胶成像系统获 得双向电泳凝胶图谱,用PD Quest图像分析软件比较分析,确定差异的特征蛋白点,从而定性鉴定不同产地蝎毒.结果 获得3个样品的蛋白质指纹图谱.分别检测出80,69和77个点,特征差异蛋白点依次为56,46和55个.结论 不同产地的东亚钳蝎蝎毒通过双向电泳分离蛋白后,表现出明显不同的蛋白点分布.

  13. Sex-Linked Chromosome Heterozygosity in Males of Tityus confluens (Buthidae): A Clue about the Presence of Sex Chromosomes in Scorpions

    Science.gov (United States)

    Adilardi, Renzo Sebastián; Ojanguren-Affilastro, Andrés Alejandro; Mola, Liliana María

    2016-01-01

    Scorpions of the genus Tityus show holokinetic chromosomes, achiasmatic male meiosis and an absence of heteromorphic sex chromosomes, like all Buthidae. In this work, we analysed the meiotic behaviour and chromosome rearrangements of a population of the scorpion Tityus confluens, characterising the cytotypes of males, females and embryos with different cytogenetic techniques. This revealed that all the females were structural homozygotes, while all the males were structural heterozygotes for different chromosome rearrangements. Four different cytotypes were described in males, which differed in chromosome number (2n = 5 and 2n = 6) and meiotic multivalent configurations (chains of four, five and six chromosomes). Based on a detailed mitotic and meiotic analysis, we propose a sequence of chromosome rearrangements that could give rise to each cytotype and in which fusions have played a major role. Based on the comparison of males, females and a brood of embryos, we also propose that the presence of multivalents in males and homologous pairs in females could be associated with the presence of cryptic sex chromosomes, with the male being the heterogametic sex. We propose that the ancestral karyotype of this species could have had homomorphic XY/XX (male/female) sex chromosomes and a fusion could have occurred between the Y chromosome and an autosome. PMID:27783630

  14. Asymmetric pulmonary edema after scorpion sting: a case report Edema pulmonar assimétrico após picada de escorpião: relato de caso

    Directory of Open Access Journals (Sweden)

    Ebrahim Razi

    2008-12-01

    Full Text Available A 12-year-old boy was referred with acute asymmetric pulmonary edema (APE four-hour after scorpion sting to Emergency department. On admission, the main clinical manifestations were: dyspnea, tachypnea, and tachycardia. Chest x-ray revealed APE predominantly on the right hemithorax. The patient was treated with oxygen, intravenous frusemide and digoxin and discharged on the sixth hospital day in a good condition. This case report emphasizes the occurrence of asymmetric pulmonary edema after severe scorpion envenomation within few hours immediately after the sting.Menino de 12 anos foi internado no Pronto Socorro, com edema pulmonar assimétrico agudo (APE, quatro horas após picada de escorpião. À admis