Journal Of Venom Research[JOURNAL]
Sun
62 papers
Characterization of crude Echis carinatus venom-induced cytotoxicity in HEK 293T cells.
Pierce RD, Kim ES, Girton LW … +3 more , McMurry JL, Francis JW, Albrecht EA
J Venom Res · 2011 · PMID 22331993
Echis carinatus (saw-scaled viper) produces potent hemorrhagic venom that causes the development of apoptotic and necrotic tissues. In this study, we used polyethyleneimine (PEI) to enhance cellular adherence, and to det...
Echis carinatus (saw-scaled viper) produces potent hemorrhagic venom that causes the development of apoptotic and necrotic tissues. In this study, we used polyethyleneimine (PEI) to enhance cellular adherence, and to determine whether the substrate attachment influenced the survival of cells treated with crude E. carinatus venom. Human embryonic kidney (HEK) 293T cells were grown for 18hr in tissue culture plates with or without polyethyleneimine (PEI), and were then stimulated with crude E. carinatus venom for 3 or 12hr. HEK 293T cells grown without PEI displayed a robust oxidative response to corresponding substrate detachment, loss of plasma membrane integrity and decreased cell viability. Cells grown on PEI adsorbed substrates demonstrated prolonged substrate attachment resulting in significantly higher cell viabilities. These observations suggest that the cytotoxicity of crude E. carinatus venom is dependent upon cellular detachment.
Inhibition of Bothrops jararacussu venom activities by Plathymenia reticulata Benth extracts.
Nicole M F, Gleidy Aa S, Karine N C … +6 more , Magali G S, José C C, Cháriston A Dal B, Márcio G Dos S, Francisco C G, Yoko OF
J Venom Res · 2011 · PMID 22331992
Hexane (HEX), dichloromethane (DM), ethyl acetate (EA) and methanol (M) extracts (0.1, 0.2 and 0.4mg/ml) were obtained via Soxhlet from Plathymenia reticulata barks (Pr). These extracts were evaluated against the myotoxi...
Hexane (HEX), dichloromethane (DM), ethyl acetate (EA) and methanol (M) extracts (0.1, 0.2 and 0.4mg/ml) were obtained via Soxhlet from Plathymenia reticulata barks (Pr). These extracts were evaluated against the myotoxicity (58%) and the irreversible in vitro neuromuscular blockade of Bothrops jararacussu (Bjssu) venom (40μg/ml) in a mouse phrenic-nerve diaphragm preparation, by using light-microscopy and conventional myographic techniques. Thin layer chromatography (TLC) was used to access the basic composition of extracts. The efficacy of the extracts was analyzed by Student's t-test or repeated measures ANOVA. The significance level was set at 5%. The Pr extracts showed a higher polyphenols content (3.75%), from which tannins take part, around 20 times more than flavonoids content (0.16%). Qualitatively, via TLC, DM and EA extracts showed higher tannins concentration than the HEX and M extracts. Pharmacologically, at 0.4mg/ml, DM was more effective (92 ± 6.2%) than EA (81.3 ±10%) = HEX, 77.2 ±4.7%) > M (54 ±10%) against the toxic effects of the venom. Morphologically, DM extract preserved intact 52.8% of the muscle fibers in the presence of the venom. We concluded that P. reticulata extracts are able to inhibit toxic effects of B. jararacussu venom, whose protective mechanism could be mediated by tannins.
Local and systemic biochemical alterations induced by Bothrops atrox snake venom in mice.
de Souza CA, Kayano AM, Setúbal SS … +7 more , Pontes AS, Furtado JL, Kwasniewski FH, Zaqueo KD, Soares AM, Stábeli RG, Zuliani JP
J Venom Res · 2012 · PMID 23487552
The local and systemic alterations induced by Bothrops atrox snake venom (BaV) injection in mice were studied. BaV induced superoxide production by migrated neutrophils, mast cell degranulation and phagocytosis by macrop...
The local and systemic alterations induced by Bothrops atrox snake venom (BaV) injection in mice were studied. BaV induced superoxide production by migrated neutrophils, mast cell degranulation and phagocytosis by macrophages. Moreover, BaV caused hemorrhage in dorsum of mice after 2hr post- injection. Three hours post-injection in gastrocnemius muscle, we also observed myonecrosis, which was assessed by the determination of serum and tissue CK besides the release of urea, but not creatinine and uric acid, indicating kidney alterations. BaV also induced the release of LDH and transaminases (ALT and AST) indicating tissue and liver abnormalities. In conclusion, the data indicate that BaV induces events of local and systemic importance.
Purification of a phospholipase A(2) from Daboia russelii siamensis venom with anticancer effects.
Khunsap S, Pakmanee N, Khow O … +6 more , Chanhome L, Sitprija V, Suntravat M, Lucena SE, Perez JC, Sánchez EE
J Venom Res · 2011 · PMID 22091349
Venom phospholipases A2 (PLA(2)) are associated with neurotoxic, myotoxic, cardiotoxic, platelet aggregation, and edema activities. A PLA(2) (Drs-PLA(2)) was purified from Daboia russelii siamensis venom by a two-step pu...
Venom phospholipases A2 (PLA(2)) are associated with neurotoxic, myotoxic, cardiotoxic, platelet aggregation, and edema activities. A PLA(2) (Drs-PLA(2)) was purified from Daboia russelii siamensis venom by a two-step purification procedure consisting of size-exclusion, followed by anion exchange high performance liquid chromatography (HPLC). The molecular weight of the Drs-PLA(2) was 13,679Da, which was determined by MALDI-TOF mass spectrometry. Its N-terminal amino acid sequence was homologous to basic PLA(2)s of viperid snake venoms. The Drs-PLA(2) had indirect hemolytic and anticoagulant activities, cytotoxic activity with a CC(50) of 65.8nM, and inhibited SK-MEL-28 cell migration with an IC(50) of 25.6nM. In addition, the Drs-PLA(2) inhibited the colonization of B16F10 cells in lungs of BALB/c mice by ∼65%.
Biological characterization of Bothrops marajoensis snake venom.
Cavalcante WL, Hernandez-Oliveira S, Galbiatti C … +8 more , Randazzo-Moura P, Rocha T, Ponce-Soto L, Marangoni S, Pai-Silva MD, Gallacci M, da Cruz-Höfling MA, Rodrigues-Simioni L
J Venom Res · 2011 · PMID 22091348
This study describes the effects of Bothrops marajoensis venom (Marajó lancehead) on isolated neuromuscular preparations of chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND). At low concentrations (1µ...
This study describes the effects of Bothrops marajoensis venom (Marajó lancehead) on isolated neuromuscular preparations of chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND). At low concentrations (1µg/ml for CBC and 5µg/ml for PND), the venom exhibited a neuromuscular blocking without any damaging effect on the muscle integrity. At higher concentration (20μg/ml for PND), together with the neuromuscular blockade, there was a moderate myonecrosis. The results show differences between mammalian and avian preparations in response to venom concentration; the avian preparation was more sensitive to venom neurotoxic effect than the mammalian preparation. The possible presynaptic mechanism underlying the neuromuscular blocking effect was reinforced by the observed increase in MEPPs at the same time (at 15min) when the facilitation of twitch tension occurred. These results indicate that the B. marajoensis venom produced neuromuscular blockade, which appeared to be presynaptic at low concentrations with a postsynaptic component at high concentrations, leading to muscle oedema. These observations demand the fractionation of the crude venom and characterization of its active components for a better understanding of its biological dynamics.
Presynaptic effect of a methanolic extract of toad (Rhinella schneideri) poison in avian neuromuscular preparation.
Rostelato-Ferreira S, Dal Belo CA, da Cruz-Höfling MA … +2 more , Hyslop S, Rodrigues-Simioni L
J Venom Res · 2011 · PMID 21994808
The neurotoxicity of a methanolic extract of toad (Rhinella schneideri) poison was examined in chick biventer cervicis preparations. The methanolic extract (1, 3, 10 and 30µg/ml) caused concentration-dependent blockade a...
The neurotoxicity of a methanolic extract of toad (Rhinella schneideri) poison was examined in chick biventer cervicis preparations. The methanolic extract (1, 3, 10 and 30µg/ml) caused concentration-dependent blockade at the three highest concentrations (time for 50% blockade, mean±SEM: 84±10, 51±3 and 12±0.8min for 3, 10 and 30µg/ml, respectively; n=6-8 each) that was preceded by significant, transient facilitation at 10μg/ml. Contractures to exogenous ACh (110μM) or KCl (20mM) were unaffected by the blockade. In curarized (d-Tc, 1μg/ml) preparations, the extract (10µg/ml) caused complete, irreversible blockade that persisted after extensive washing. The extract did not significantly alter the creatine kinase release or morphology of biventer cervicis muscle. These results indicate that the methanolic extract of R. schneideri poison acts primarily presynaptically to enhance neurotransmitter release in this avian preparation.
The neuromuscular activity of Micrurus pyrrhocryptus venom and its neutralization by commercial and specific coral snake antivenoms.
Camargo TM, de Roodt AR, da Cruz-Höfling MA … +1 more , Rodrigues-Simioni L
J Venom Res · 2011 · PMID 21858249
The neuromuscular activity ofMicrurus pyrrochryptus venom was studied in chick biventer cervicis (BC) and mouse phrenic nerve-diaphragm (PND) preparations. The venom (0.5-50μg/ml) caused irreversible, time- and concentra...
The neuromuscular activity ofMicrurus pyrrochryptus venom was studied in chick biventer cervicis (BC) and mouse phrenic nerve-diaphragm (PND) preparations. The venom (0.5-50μg/ml) caused irreversible, time- and concentration-dependent blockade, with BC being more sensitive than PND (50% blockade with 10μg/ml in 22±;3min and 62±4min, respectively; mean±SEM, n=6; p<0.05). In BC preparations, venom (0.5μg/ml) progressively abolished ACh-induced contractures, whereas contractures to exogenous KCl and muscle twitches in curarized preparations were unaffected. The venom neither altered creatine kinase release (venom: 25.8±1.75IU/l vs control: 24.3±2.2IU/l, n=6, after 120min), nor it caused significant muscle damage (50μg of venom/ml vs control: 3.5±0.8% vs 1.1±0.7% for PND; 4.3±1.5% vs 1.2±0.5% for BC, n=5). The venom had low PLA(2) activity. Neurotoxicity was effectively neutralized by commercial Micrurus antivenom and specific antivenom. These findings indicate that M. pyrrhocryptus venom acts postsynaptically on nicotinic receptors, with no significant myotoxicity.
The in vitro toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Hypnale).
Maduwage K, Hodgson WC, Konstantakopoulos N … +3 more , O'Leary MA, Gawarammana I, Isbister GK
J Venom Res · 2011 · PMID 21677795
Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopa...
Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopathy and acute renal failure. Currently there are three nominal species of this genus: H. hypnale, H. zara and H. nepa. This study investigates the biochemical and pharmacological properties of the venoms from the three Hypnale species in Sri Lanka. The three Hypnale venoms had similar chromatographic profiles using reverse phase high performance liquid chromatography and fractions with procoagulant activity were identified. Hypnale venoms had potent cytotoxicity in cultured rat aorta smooth muscle cells with similar IC(50) values. The venoms had weak neurotoxic and myotoxic activity in the isolated chick biventer muscle preparation. They had mild procoagulant activity with close MCC(5) values and also phospholipase activity. Locally available polyvalent antivenom did not neutralise any venom effects. The study demonstrates that the three Hypnale venoms are similar and cytotoxicity appears to be the most potent effect, although they have mild procoagulant activity. These findings are consistent with clinical reports.
Hypericum brasiliense plant extract neutralizes some biological effects of Bothrops jararaca snake venom.
Assafim M, de Coriolano EC, Benedito SE … +5 more , Fernandes CP, Lobo JF, Sanchez EF, Rocha LM, Fuly AL
J Venom Res · 2011 · PMID 21654896
Alternative treatments for snake bite are currently being extensively studied, and plant metabolites are considered good candidates for such purpose. Here, the ability of a crude ethanolic extract of Hypericum brasiliens...
Alternative treatments for snake bite are currently being extensively studied, and plant metabolites are considered good candidates for such purpose. Here, the ability of a crude ethanolic extract of Hypericum brasiliense plant in neutralizing Bothrops jararaca snake venom was investigated by in vitro (coagulation, hemolysis or proteolysis) and in vivo (hemorrhage, lethality and edema) biological assays. We describe for the first time the ability of H. brasiliense extracts to inhibit some pharmacological effects of a Brazilian snake venom. Inhibitory assays were performed by incubating B. jararaca venom with H. brasiliense extracts for 30min at room temperature before the assays were performed. The results showed that H. brasiliense extracts impaired lethality, edema, hemorrhage, hemolysis, proteolysis as well as fibrinogen or plasma clotting induced by B. jararaca venom. This indicates that H. brasiliense extracts can provide promising agents to treat B. jararaca envenomation.
Suramin inhibits the early effects of PLA(2) neurotoxins at mouse neuromuscular junctions: A twitch tension study.
Fathi B, Harvey AL, Rowan EG
J Venom Res · 2011 Jan · PMID 21544175
Several phospholipase A(2) (PLA(2)) neurotoxins from snake venoms can affect acetylcholine release at the neuromuscular junction. In isolated nerve-muscle preparations three distinct phases have been described for this p...
Several phospholipase A(2) (PLA(2)) neurotoxins from snake venoms can affect acetylcholine release at the neuromuscular junction. In isolated nerve-muscle preparations three distinct phases have been described for this phenomenon: An initial transient decrease in twitch tension; a second facilitatory phase during which twitch height is greater than control twitch height; and the last phase which causes a reduction in twitch height that finally results in paralysis. Suramin has been reported to inhibit the toxic effects of β-bungarotoxin and another PLA(2) neurotoxin, crotoxin in vitro and in vivo. We have further examined the effects of suramin on the three phases of the effects of the presynaptic PLA(2) neurotoxins β-bungarotoxin, taipoxin and ammodytoxin on mouse phrenic nerve-hemidiaphragm preparations. When preparations were pre-treated with suramin (0.3mM), the early biphasic effects (depression followed by facilitation) were abolished, and the time taken for final blockade induced by β-bungarotoxin, taipoxin and ammodytoxin A was significantly prolonged. In contrast, suramin did not significantly affect the facilitation induced by the potassium channel blocking toxin dendrotoxin I when applied under the same conditions. In addition, application of 0.3mM suramin did not prevent the facilitatory actions of 3,4-diaminopyridine (3,4-DAP) and tetraethylammonium chloride (TEA). Overall, the mechanism whereby suramin reduces the effects of PLA(2) neurotoxins remains elusive. Since suramin reduces both enzyme-dependent and enzyme-independent effects of the toxins, suramin is not acting as a simple enzyme inhibitor. Furthermore, the observation that suramin does not affect actions of standard K(+) channel blockers suggests that suramin does not stabilise nerve terminals.
TTX, cations and spider venom modify avian muscle tone in vitro.
Herzig V, Hodgson WC, Rowan EG
J Venom Res · 2011 Jan · PMID 21544174
Agents that reduce skeletal muscle tone may have a number of useful clinical applications, e.g., for muscle spasticity and other muscle disorders. Recently, we reported that the venoms of two species of Australian therap...
Agents that reduce skeletal muscle tone may have a number of useful clinical applications, e.g., for muscle spasticity and other muscle disorders. Recently, we reported that the venoms of two species of Australian theraphosid (Araneae, Theraphosidae) spiders (Coremiocnemis tropix and Selenotholus foelschei) reduced the baseline tension of chick biventer cervicis nerve-muscle preparation. The purpose of this study was to determine the underlying physiology mediating the change in muscle tension, which was addressed by conducting isometric tension experiments. We found that MgCl(2) (20mM), CaCl(2) (20mM), tetrodotoxin (1μM) or C. tropix venom (2μl/ml) produced a similar decrease in baseline tension, whereas d-tubocurarine (100μM), gadolinium (1mM), verapamil (10mM), an increase in osmotic pressure by the addition of glucose (40mM), or the presence/absence of electrical stimulation did not produce a significant change in baseline tension. We suggest that mechanosensitive or muscle TTX-sensitive sodium channels are activated during muscle stretch. This may have implications for the treatment of stretch induced muscle damage.
Ontogenesis, gender, and molting influence the venom yield in the spider Coremiocnemis tropix (Araneae, Theraphosidae).
Herzig V
J Venom Res · 2010 Dec · PMID 21544186
The demand for spider venom increases along with the growing popularity of venoms-based research. A deeper understanding of factors that influence the venom yield in spiders would therefore be of interest to both commerc...
The demand for spider venom increases along with the growing popularity of venoms-based research. A deeper understanding of factors that influence the venom yield in spiders would therefore be of interest to both commercial venom suppliers and research facilities. The present study addresses the influence of several factors on the venom yield by systematically analyzing the data obtained from 1773 electrical milkings of the Australian theraphosid spider Coremiocnemis tropix. Gender and ontogenesis were found to cause a major effect on the venom yield, as adult female C. tropix yielded significantly more venom than adult males. During ontogenesis, the venom yield increased with increasing size of the spiders. Furthermore, a significant reduction in the venom yield during the 50-day time interval preceding a molt was found. On the other hand, extended milking intervals (up to 449 days) and different states of nutrition (as an indication of how well the spider was fed) did not significantly affect the venom yield. Overall, the present findings suggest that venom production in spiders is carefully balanced between the demand for venom and the energy costs associated with its production. It can therefore be concluded that, in line with the venom optimization hypothesis, venom is a precious resource for spiders, which have implemented control mechanisms to ensure economical venom production and usage.
Deep coma and hypokalaemia of unknown aetiology following Bungarus caeruleus bites: Exploration of pathophysiological mechanisms with two case studies.
Gawarammana IB, Mudiyanselage Kularatne SA, Kularatne K … +4 more , Waduge R, Weerasinghe VS, Bowatta S, Senanayake N
J Venom Res · 2010 Dec · PMID 21544185
Bungarotoxin present in Bungarus caeruleus (BC) causes life threatening respiratory muscle paralysis. Deep coma and hypokalaemia have been observed in a significant proportion of patients, but the cause is unknown. We po...
Bungarotoxin present in Bungarus caeruleus (BC) causes life threatening respiratory muscle paralysis. Deep coma and hypokalaemia have been observed in a significant proportion of patients, but the cause is unknown. We postulate the likely mechanism behind these two phenomena. We studied clinical details of two patients admitted with deep coma and performed electroencephalograms (EEG) and brain stem auditory and visual evoked potentials (BAEP and VEP). Daily serum potassium was measured along with urinary potassium excretion as a marker of total extracellular body potassium. Both patients had no brain stem reflexes on admission and the EEG revealed absent alpha and delta activity and presence of dominant theta activity. Alpha rhythm returned on the 3(rd) day in one patient, while in the other it did not, and the latter patient died on the 13(th) day due to disseminated intravascular coagulation. BAEP were delayed and VEP were absent in the deceased patient. Both had low serum potassium and low urinary potassium excretion. Replacement of potassium (up to 1.5mmol/kg/day) did not improve serum potassium and urinary potassium excretion. Absent alpha and delta activity in EEG and delayed BAEP and absent VEP are suggestive of a central action of the venom on both the cortical and brain stem neurones. Persistently low serum potassium and reduced urinary potassium excretion are suggestive of intracellular shift as the causative mechanism of hypokalaemia.
Differences in venom toxicity and antigenicity between females and males Tityus nororientalis (Buthidae) scorpions.
De Sousa L, Borges A, Vásquez-Suárez A … +6 more , Op den Camp HJ, Chadee-Burgos RI, Romero-Bellorín M, Espinoza J, De Sousa-Insana L, Pino-García O
J Venom Res · 2010 Oct · PMID 21544184
Venom from male and female specimens of the medically important Venezuelan scorpion Tityus nororientalis have been compared. Males showed a significantly higher venom yield (2.39mg/individual) compared to female scorpion...
Venom from male and female specimens of the medically important Venezuelan scorpion Tityus nororientalis have been compared. Males showed a significantly higher venom yield (2.39mg/individual) compared to female scorpions (0.98mg/individual). Female venom was significantly more toxic than that of males, with a median lethal dose (LD(50)) in C57BL/6 mice of 9.46 μg venom protein/gm body weight [95% confidence interval (8.91-9.94)] whereas LD(50) for males was 13.36(12.58-14.03) μg/gm. Mass spectral analyses by MALDI-TOF revealed differences in venom composition between males and females. From a clinical standpoint, the time course of toxicity course indicated a tendency, in the case of the female venom, to elicit the earlier occurrence of severe signs such as sialorrhea, dyspnea (bradypnea/apnea) and exophthalmus particularly in the late toxicity phase. Female venom was significantly less efficient than male venom to inhibit the binding of anti-T. discrepans antibodies to immobilized T. discrepans venom in ELISA assays, suggesting sex-related differences in the bioactive surfaces of T. nororientalis toxins. These results indicate that males and females of T. nororientalis produce venoms with different composition and activity which may have epidemiological implications.
Heparin at low concentration acts as antivenom against Bothrops jararacussu venom and bothropstoxin-I neurotoxic and myotoxic actions.
Rostelato-Ferreira S, Leite GB, Cintra AC … +3 more , da Cruz-Höfling MA, Rodrigues-Simioni L, Oshima-Franco Y
J Venom Res · 2010 Oct · PMID 21544183
Heparin has been shown to antagonize myotoxic effects of crotaline venoms. Here a very low heparin concentration (LHC) was examined in its ability to antagonize the neurotoxic/myotoxic effects of Bothrops jararacussu ven...
Heparin has been shown to antagonize myotoxic effects of crotaline venoms. Here a very low heparin concentration (LHC) was examined in its ability to antagonize the neurotoxic/myotoxic effects of Bothrops jararacussu venom and its phospholipase A(2) myotoxin, bothropstoxin-I (BthTX-I), in an in vitroz nerve-muscle preparation and in mice gastrocnemius. Normalization of results was done by assays with commercial antibothropic antivenom (CBA). LHC (1IU/ml) added to the incubation bath reduced by 4- and 4.5-fold (vs 2.8- and 2.5-fold by CBA) the neuromuscular paralysis, by 5.4 and 4.4-fold (vs 2.5- and 13.3-fold by CBA) the percentage of fibers damaged and by 6- and 1.7-fold (vs 30- and 1.6-fold by CBA) the CK activity induced by B. jararacussu and BthTX-I, respectively. Protamine sulphate added 15min after the incubation of the preparation with LHC+venom, avoided the LHC neutralizing effect against venom neurotoxicity. This strongly attests that given the polycationic nature of protamine, it probably complexed with the polyanionic heparin making it unattainable for binding to basic components of venom, reducing toxicity. Since heparin antagonism is generally stronger against venom effects than is myotoxin we discuss that other venom components than the BthTX-I are likely target for the antagonism promoted by the polyanionic heparin.
The pharmacokinetics of Iranian scorpion Odonthubuthus doriae venom and the available antivenom.
Jalali A, Moazen S, Babaee M … +2 more , Dadashzade S, Droudi A
J Venom Res · 2010 Oct · PMID 21544182
In Iran intramuscular (IM) administration of antivenoms is used for the treatment of human scorpion envenoming of six medically dangerous scorpion species, including Odonthubuthus doriae (O. doriae). The purpose of the c...
In Iran intramuscular (IM) administration of antivenoms is used for the treatment of human scorpion envenoming of six medically dangerous scorpion species, including Odonthubuthus doriae (O. doriae). The purpose of the current study is to investigate the efficiency of the intramuscular route and the delay of injection on the neutralizing effect of the available polyvalent antivenom. We compared the pharmacokinetics parameters of O. doriae venom and its antivenom. 5µg (131)I-labeled venom and 0.2µl of antivenom were administered via subcutaneous (SC) or IM into rats. Blood samples were taken at various predetermined time intervals during a 24hr period for the venom and a 360min period for the antivenom. The radio-iodination was carried out using the chloramin-T method. The results showed that pharmacokinetic parameters of the venom were T(1/2) = 496.53min; V(d) = 1522ml/kg; Cl = 2.12 ml/kg/min; mean resident residual time (MRT) = 555.77min, and for the antivenom T(1/2) = 902.13min, V(d) = 666.66 ml/kg , Cl = 0.512 ml/kg/min and MRT = 1292min. The total body clearance of the venom is relatively low in agreement with a high mean residence time. Higher AUC and C(max) values for the antivenom as well as its longer residence time indicate that the venom and antivenom are expected to have enough opportunity to interact in the tissue compartments. Over, this study suggests that the intramuscular administration of a single dose of antivenom (2 vials each of 5ml) based on current protocol in Iran is a suitable route for the treatment of envenomation with O. doriae. Prudently, further clinical studies with similar aims need to be carried out to confirm these findings in human victims.
A novel bioactive peptide from wasp venom.
Chen L, Chen W, Yang H … +1 more , Lai R
J Venom Res · 2010 Sep · PMID 21544181
Wasp venoms contain a number of pharmacologically active biomolecules, undertaking a wide range of functions necessary for the wasp's survival. We purified and characterized a novel bioactive peptide (vespin) from the ve...
Wasp venoms contain a number of pharmacologically active biomolecules, undertaking a wide range of functions necessary for the wasp's survival. We purified and characterized a novel bioactive peptide (vespin) from the venoms of Vespa magnifica (Smith) wasps with unique primary structure. Its amino acid sequence was determined to be CYQRRVAITAGGLKHRLMSSLIIIIIIRINYLRDNSVIILESSY. It has 44 residues including 15 leucines or isoleucines (32%) in the sequence. Vespin showed contractile activity on isolated ileum smooth muscle. The cDNA encoding vespin precursor was cloned from the cDNA library of the venomous glands. The precursor consists of 67 amino acid residues including the predicted signal peptide and mature vespin. A di-basic enzymatic processing site (-KR-) is located between the signal peptide and the mature peptide. Vespin did not show similarity with any known proteins or peptides by BLAST search, suggesting it is a novel bioactive peptide from wasp venoms.
Non-covalent interaction of phospholipase A(2) (PLA(2)) and kaouthiotoxin (KTX) from venom of Naja kaouthia exhibits marked synergism to potentiate their cytotoxicity on target cells.
Mukherjee AK
J Venom Res · 2010 Sep · PMID 21544180
Present study shows that non-covalent interaction of kaouthiotoxin (KTX) with their respective pohospholipase A(2) (PLA(2)) from the venom of N. kaouthia displayed marked synergism to exert cytotoxicity without altering...
Present study shows that non-covalent interaction of kaouthiotoxin (KTX) with their respective pohospholipase A(2) (PLA(2)) from the venom of N. kaouthia displayed marked synergism to exert cytotoxicity without altering the biochemical properties of PLA(2). For example, although NK-PLA(2) or KTX alone did not induce appreciable hemolysis of washed human erythrocytes; however, the hemolytic potency of NK-PLA(2): KTX complex was significantly higher. Identically, selective lysis of virus infected Sf9 and normal Tn insect cells was further enhanced by the cognate NK-PLA(2): KTX complex as compared to individual components of the complex. Gas-chromatographic analysis of fatty acids released from intact erythrocytes by cytotoxic action of individual NK-PLA(2) and NK-PLA(2): KTX complex demonstrated that ratio between saturated fatty acids (SFA) and unsaturated FA (UFA) was increasing with time of hydrolysis of RBC either in the case of NK-PLA(2) or NK-PLA(2)-KTX complex suggesting NK-PLA(2)-KTX complex apparently displayed the more preference for glycerophospholipids with SFAs on the sn-2 position. Therefore, it may be suggested that KTX first destabilize the target cell membrane followed by higher enzymatic activity of PLA(2) on dislocated and disorganized phospholipid bilayers resulting in a significantly higher (p < 0.05) membrane damage by NK-PLA(2)-KTX complex compared to individual components of the complex.
Effect of honey bee venom on differentiation of cholinergic neurons.
Kouchesfahani HM, Nabiuni M, Parivar K … +1 more , Ebrahimi S
J Venom Res · 2010 Sep · PMID 21544179
Mouse P19 embryonic carcinoma (EC) cells are pluripotent and can differentiate into a population consisting largely of neurons and glia cells using a concentration of 5x10(-7)M of retinoic acid (RA). Thus, P19 EC cells a...
Mouse P19 embryonic carcinoma (EC) cells are pluripotent and can differentiate into a population consisting largely of neurons and glia cells using a concentration of 5x10(-7)M of retinoic acid (RA). Thus, P19 EC cells are a good model system to study events occurring during the critical phases of neuronal differentiation, in vitro. Honey bee venom (BV) consists of mellitin, phospholipase A2, apamin and several other bioactive substances. Previous studies have shown that mellitin and phospholipase A2 - two major components of BV - play an important role in the differentiation of neurons. The purpose of this study was to examine effects of BV and RA on the differentiation of cholinergic neuron in P19 cell line. Preliminary results obtained from morphological examination showed that six days after treatment with 5x10(-7)M RA, P19 cells produced processes, and gradually obtained neuronal phenotype at approximately day-10. All cells then died at day-11. P19 cells treated with 1.3μg/ml BV produced processes on day-6 and neurons appeared in the next four days. They then proceeded to total size until day-10 and produced elongated processes; however, all cells died on day-11. Using BV and RA together had the same effect but more pronounced differentiating results. It can be concluded that applying BV with RA has an additive effect on cell differentiation and proliferation. The presence of acetylcholinesterase (AChE), frequently used as a marker for neuronal differentiation, was also determined and found using DTNB.
Proteolytic activity of Elapid and Viperid Snake venoms and its implication to digestion.
Bottrall JL, Madaras F, Biven CD … +2 more , Venning MG, Mirtschin PJ
J Venom Res · 2010 Sep · PMID 21544178
Testing whether venoms may aid in digestion of the prey, eleven snake venoms were compared for the presence of proteases and endopeptidases that function in alkaline pH conditions. In vitro experiments examined the relat...
Testing whether venoms may aid in digestion of the prey, eleven snake venoms were compared for the presence of proteases and endopeptidases that function in alkaline pH conditions. In vitro experiments examined the relative protease and endopeptidase activity of the venoms, which involved combining bovine muscle and snake venom in a buffered solution, encased within dialysis tubing. This mixture was then incubated at room temperature (∼20°C) for 24hr, with constant shaking. Bicinchoninic acid (BCA) assay and ninhydrin assay were used to determine peptide and amino acid concentrations. Histological and immunohistochemical investigations using N. kaouthia venom confirmed in vitro findings. Results show that B. arietans venom generated the highest amount of protein/peptides and amino acids in the dialysates, while O. scutellatus, N. ater niger and P. textilis venom did not show any significant protein degradation under alkaline conditions. Histological examination revealed varying degrees of muscle cell damage for each of the venom investigated, and the immunohistochemical study on N. kaouthia venom showed that the venom penetrated the muscle tissue to a significant degree. In vitro assays and histological results indicate that particular venoms may possess the ability to enhance digestion of bovine muscle tissue.
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