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PubMed1997

Bov-B long interspersed repeated DNA (LINE) sequences are present in Vipera ammodytes phospholipase A2 genes and in genomes of Viperidae snakes.

Ammodytin L is a myotoxic Ser49 phospholipase A2 (PLA2) homologue, which is tissue-specifically expressed in the venom glands of Vipera ammodytes. The complete DNA sequence of the gene and its 5' and 3' flanking regions has been determined. The gene consists of five exons separated by four introns. Comparative analysis of the ammodytin L and ammodytoxin C genes shows that all intron and flanking sequences are considerably more conserved (93-97%) than the mature protein-coding exons. The pattern of nucleotide substitutions in protein-coding exons is not random but occurs preferentially on the first and the second positions of codons, which suggests positive Darwinian evolution for a new function. An Ruminantia specific ART-2 retroposon, recently recognised as a 5'-truncated Bov-B long interspersed repeated DNA (LINE) sequence, was identified in the fourth intron of both genes. This result suggests that ammodytin L and ammodytoxin C genes are derived by duplication of a common ancestral gene. The phylogenetic distribution of Bov-B LINE among vertebrate classes shows that, besides the Ruminantia, it is limited to Viperidae snakes (Vipera ammodytes, Vipera palaestinae, Echis coloratus, Bothrops alternatus, Trimeresurus flavoviridis and Trimeresurus gramineus). The copy number of the 3' end of Bov-B LINE in the Vipera ammodytes genome is between 62,000 and 75,000. The absence of Bov-B LINE at orthologous positions in other snake PLA2 genes indicates that its retrotransposition in the V. ammodytes PLA2 gene locus has occurred quite recently, about 5 My ago. The amplification of Bov-B LINEs in snakes may have occurred before the divergence of the Viperinae and Crotalinae subfamilies. Due to its wide distribution in Viperidae snakes it may be a valuable phylogenetic marker. The neighbor-joining phylogenetic tree shows two clusters of truncated Bov-B LINE, a Bovidae and a snake cluster, indicating an early horizontal transfer of this transposable element.

Animals↗

PubMed2000

Disseminated intravascular coagulation after cerastes vipera envenomation in a 3-year-old child: a case report.

This study presents a case of severe disseminated intravascular coagulation (DIC) in a 3-year-old child following envenomation by the snake, Cerastes vipera. A literature search revealed very few similar cases. We describe a child who was bitten in his left foot by a snake identified as a C. vipera. Initial symptoms were relatively benign. Local signs included a hemorrhagic vesicle at the site of the bite with marked swelling of the entire leg. Twenty-four hours later, the child developed severe bleeding due to DIC, which lasted 5 days and required repeated administration of blood and blood products and total exchange transfusion. The patient was discharged from the hospital after 7 days in good condition. To the best of our knowledge, severe DIC following envenomation by a C. vipera has not been previously described in the literature. Treatment was essentially supportive. The case report indicates that a specific antivenin against this snake's venom should be made available in our area.

Animals↗

PubMed1998

Biochemical characterization of lebetase, a direct-acting fibrinolytic enzyme from Vipera lebetina snake venom.

Lebetase, the fibrinolytic enzyme isolated from Vipera lebetina (Levantine viper) snake venom is a metalloenzyme that contains one mole of Zn2+ and one mole of Ca2+ per mole of protein. Lebetase is inhibited by dithiothreitol, suggesting that disulfide bonds are necessary for holding the structure. Vipera lebetina venom contains several isoforms of lebetase in the interval of pI 4.6-5.4. Two lebetase fractions I (pI of the main component 5.0) and II (pI of the main component 5.3) degrade fibrin and fibrinogen by hydrolysis of the alpha and beta chains. The molecular weights of the cleavage products produced by the two different lebetase fractions are identical. The metal ions, Cd2+, Cu2+, Co2+, inhibit fibrinolytic and caseinolytic activity of lebetase I and II. Using mass spectrometry we characterized differences in molecular masses of lebetase I and II (22719 Da and 22912 Da). Vipera lebetina venom from a single snake contains mainly one form of lebetase. Lebetase I is more stable at low pH than lebetase II. The lebetases I and II inhibit platelet aggregation induced by ADP in a dose-dependent manner.

Adenosine Diphosphate↗

PubMed1988

Immunocytochemical localization of peptides in the endocrine pancreas of the snakes Vipera aspis and Natrix maura.

The endocrine pancreas of Vipera aspis and Natrix maura has been investigated by immunocytochemistry for the presence of six peptides reported to occur in Mammals or in Reptiles. Gastrin/CCK and PP were absent in the endocrine cells, VIP was located within nerve terminals only. Insulin, Glucagon, and Somatostatin were localized both in Vipera and Natrix, generally with a ring of D (Somatostatin) cells surrounding a core of Glucagon (A) and Insulin (B) producing cells; however frequent clusters of D cells are intermingled with the other endocrine cells. Statistical evaluations on the percentages of these 3 cell types showed preponderance of A cells in Natrix whereas in Vipera no significant difference was found between the number of A and B cells. The D cells showed a uniform distribution in the pancreas of the 2 studied species, in any case with a percentage slightly inferior to those of B cells.

Animals↗

PubMed1999

Suspected Vipera palaestinae envenomation in three cats.

Vipera palaestinae is the only venomous snake in Israel whose envenomation is clinically significant. It is found in most of the populated areas of the country. The venom of Vipera palaestinae has hemorrhagic and neurotoxic activity. Viper snake envenomation always demonstrates local effects with or without systemic effects. Cats are considered more resistant to snake bites than other animals. Although several case reports of snakebites in cats have been published, this is the first report which describes cases of cats suspected of being bitten by Vipera palaestinae. These cases differ in their severity and in their clinical presentation. Hemoconcentration occurred in 2 cases; and anemia, hypoproteinemia, hemolysis and the appearance of nucleated erythrocytes in another. Thrombocytopenia varied from mild to moderate to severe. These variations reflect the stage and severity of envenomation, and may be due to factors in the snake and/or victim and the time lapsed since the bite occurred.

Anemia↗

PubMed2002

Eight cases of acute renal failure from Vipera russelli formosensis venom after administration of antivenom.

The six-valent antivenom from Vipera russelli formosensis in Taiwan has recently become available in Taiwan. Between June 1998 and December 2001 8 Vipera russelli formosensis snakebite victims were treated with antivenom within 24 h of snakebite. Bleeding stopped and coagulopathy improved after antivenom use, and neurotoxic symptoms were mild. Prothrombin time was prolonged on the 1st day and thrombocytopenia changed within 2 d. In the majority of cases, renal dysfunction persisted for several days after coagulation abnormalities normalized: 3 cases required hemodialysis. Although Vipera russelli formosensis antivenom is capable of preventing hemorrhage, antivenom administration may not alter the course of severe renal damage.

Acute Kidney Injury↗

PubMed1993

A sensitive fluorogenic enzyme linked immunosorbent assay for the detection of Vipera russelli venom.

A highly sensitive fluorogenic enzyme-linked immunosorbent assay (FELISA) has been adapted for the detection of Vipera russelli venom. The assay sensitivity was observed to be 0.1 pg/ml (1 x 10(-13) g/ml). Venoms from snakes of the Vipera group exhibited a high degree of cross-reactivity when tested with the antibody raised against V. russelli venom. With the exception of venom from Naja naja, all the tested venoms from unrelated families also showed cross-reactivity. This procedure is useful for detecting snake venom or its components in biological samples.

Animals↗

PubMed1994

Purification from Vipera lebetina (desert adder) venom of a protein that depletes human complement.

A rapid and efficient procedure for purification from Vipera lebetina venom of a low molecular weight anticomplement protein is described. The procedure used gel filtration on Superose 12, followed by ion-exchange chromatography on a Mono Q column. The purified protein migrated on SDS-PAGE as a single band of about 25,000 Da under nonreducing conditions and as a band of 16,000 Da under reducing conditions. Its isoelectric point was estimated to be 7.6 +/- 0.1. The isolated Vipera lebetina protein was found to decrease the hemolytic activity in human serum measured by assays for classical pathway and alternative pathway activation. The loss of the complement activity could be ascribed, at least in part, to a proteolytic cleavage of the alpha chains of C3 and C4. This protein was also found to be without action on human blood coagulation and on purified fibrinogen and Factor B.

Blood Coagulation↗

PubMed1998

Positive Darwinian selection in Vipera palaestinae phospholipase A2 genes is unexpectedly limited to the third exon.

The venom of Vipera palaestinae contains a two-component toxin, consisting of an acidic phospholipase A2 (PLA2) and a basic protein. Here we report the cloning and sequence analysis of the complete V. palaestinae PLA2 genes. Since in all Viperidae PLA2 multigene families the 5' and 3' flanking regions are highly conserved, we designed oligonucleotide primers that allow amplification of the whole PLA2 multigene family in a single step. The structural organization of both genes is the same as in the Vipera ammodytes PLA2 multigene family, there being five exons separated by four introns. Comparison of V. palaestinae PLA2 genes with other Viperidae PLA2 genes has shown that the structural organization of the genes and the nucleotide sequence of all introns and flanking regions are highly conserved, whereas the third exon clearly shows a higher number of amino acid replacements, an indication of positive Darwinian selection. The positive Darwinian selection is surprisingly limited to the third exon, in contrast to other Viperidae PLA2 genes, where it is present in all mature protein coding exons.

Amino Acid Sequence↗

PubMed1977

The neutralization mechanism of Vipera palaestinae neurotoxin by a purified factor from homologous serum.

The serum of Vipera palaestinae contains two separate factors which neutralize the hemorrhagic and the neurotoxic activities of its venom. The purified antineurotoxic factor shows one major band in disc electrophoresis and an 800-fold increase in specific activity. Its molecular weight is approximately 56 000 and the isoelectric point is 4.0. These data, together with the failure to form precipitin lines in immuno-diffusion tests, suggest that the antineurotoxic factor of Vipera palaestinae serum is probably an albumin-like or alpha-globulin fraction rather than an immunoglobulin fraction. In vivo experiments show that the neutralizing protein does not protect or block the neurotoxin target sites. When the neurotoxic fraction is injected into mice intravenously at different intervals following injection of the snake serum, the neutralizing activity decreases with time. Experiments carried out in vitro show that the antineurotoxic factor is inactivated upon heating at 95 degrees C for 10 min but resists boiling when mixed with the neurotoxic component, suggesting the formation of a thermostable complex between the two components. This assumed complex dissociates at pH 2.5 and the neurotoxic activity reappears. Further investigation of the reaction with 131I-labeled neurotoxin and neurotoxin components shows that a stable complex is formed between the neutralizing protein and one of the synergistic components of the neurotoxic fraction.

Animals↗

PubMed1987

Interaction of aristolochic acid with Vipera russelli phospholipase A2: its effect on enzymatic and pathological activities.

Aristolochic acid, an alkaloid from the plant Aristolochia species, interacts with the major basic phospholipase A2 from Vipera russelli venom. It is an uncompetitive inhibitor with a Ki of 9.9 X 10(-4)M when phosphatidylcholine is used as substrate. The inhibition of direct and indirect hemolysis is higher compared to the inhibition of phosphatidylcholine hydrolysis. Edema-inducing activity of Vipera russelli phospholipase A2 is inhibited by aristolochic acid when injected either as a mixture or separately. Both i.m. and i.p. administration of aristolochic acid following phospholipase injection are equally effective in inhibiting edema. The alkaloid inhibits the edema-inducing activity as soon as it reaches the site, but does not aid in recovery. Aristolochic acid failed to inhibit other pathological activities of the enzyme.

Animals↗

PubMed1992

An affinity purified ovine antivenom for the treatment of Vipera berus envenoming.

A novel antivenom for treating patients with Vipera berus bite has been developed. Sheep are immunised monthly with relatively small amounts of Vipera berus (common adder) venom and the resultant antisera pooled. The immunoglobulin fraction is precipitated with sodium sulphate then cleaved with papain to produce Fab fragments. Finally, those Fab fragments that are directed specifically against components in the venom are purified by affinity chromatography on columns comprising V. berus venom coupled to cyanogen bromide activated Sepharose 4B. The resultant product is some three times more effective than the non-purified Fab in protecting mice against the lethal venom effects.

Animals↗

PubMed1993

Biological and biochemical activities of Vipera berus (European viper) venom.

Vipera berus is widely distributed throughout the northern part of Europe and Asia. Characterization of several toxic effects of its venom in the mouse, as well as of in vitro enzymatic activities was performed. Vipera berus venom displayed in vitro proteolytic, fibrinolytic, anticoagulant, and phospholipase A2 activities. The i.p. LD50 of the venom for Swiss mice was 0.86 micrograms/g (95% confidence limits 0.71-1.01 microgram/g). Significant local tissue-damaging effects, including edema, hemorrhage and myonecrosis, were observed. The local edema was characterized by rapid onset, reaching a maximum after 0.5-1 hr, and with dose-dependent persistence. The hemorrhagic potency was measured by a skin test, giving a minimum hemorrhagic dose value of 3.2 micrograms. The venom also induced a moderate local myonecrosis, evidenced by histological evaluation of injected tissue (gastrocnemius), and by biochemical parameters (increase of plasma creatine kinase activity, and decrease of muscle residual MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide)-reducing activity). Characterization of the venom by SDS-polyacrylamide gel electrophoresis revealed 10 (reduced) or 11 (unreduced) main protein bands, which were further analyzed in relation to mol. wt and relative concentration by densitometry. A rabbit antiserum to V. berus venom recognized all main venom bands by immunoblotting. This antiserum cross-reacted to a variable extent with several crotaline venoms, as assessed by enzyme immunoassay.

Animals↗

PubMed1996

Similar effectiveness of Fab and F(ab')2 antivenoms in the neutralization of hemorrhagic activity of Vipera berus snake venom in mice.

The ability of two antivenoms to Vipera spp., consisting of Fab (Therapeutic Antibodies), or of F(ab')2 (Zagreb Institute of Immunology) antibody fragments, to neutralize the hemorrhagic activity of Vipera berus snake venom in mice, was compared. First, the neutralizing potency was determined by in vitro preincubation of venom and antivenom, followed by intradermal injection into mice and subsequent measurement of the hemorrhagic area. Both antivenoms had the same anti-hemorrhagic potency, in terms of volume of antivenom/mass of venom, with an estimated ED50 (50% reduction of the effect) of 80 microliters antivenom/mg venom. Therefore, no adjustments in dose were necessary for subsequent in vivo comparative experiments. When the antivenoms were administered intravenously into mice immediately after intradermal venom injection, there was no difference in their effectiveness in reducing hemorrhagic lesions, at all doses tested. These results indicate that neutralization of local hemorrhagic activity of V. berus venom in vivo is not improved by the use of the smaller Fab fragments, in comparison to F(ab')2, when equivalent neutralizing units are injected. However, this does not exclude the possibility that other clinically relevant venom effects may be neutralized with different efficiency by Fab or F(ab')2 fragments of antibodies.

Animals↗

PubMed1993

Isolation, partial characterization and complete amino acid sequence of the toxic phospholipase A2 from the venom of the common viper, Vipera berus berus.

A basic, toxic phospholipase A2 was purified from the venom of Vipera berus berus (Vbb) by a single purification step, using hydrophobic chromatography. The primary structure of isolated protein was established from peptides generated by Gly-specific papaya proteinase IV, beta-trypsin, CNBr and mild acid hydrolysis. The enzyme consists of a single chain of 122 amino acid residues with 14 Cys in positions characteristic for the phospholipase A2 subgroup IIA. As far as we know, this is the first complete Vipera berus phospholipase A2 amino acid sequence reported.

Amino Acid Sequence↗

PubMed1985

Isolation and characterization of nerve growth factor from Vipera lebetina (snake) venom.

Nerve growth factor from Vipera lebetina venom was purified by gel filtration and ion exchange chromatography steps. The NGF preparation obtained is a glycoprotein with weak arginine esterase activity. It hydrolyzes benzoylarginine ethyl ester (BAEE). Vipera lebetina NGF consists of multiple forms of protein with pI in the interval 9-10.5. All isoforms have identical molecular weights of 32,500.

Animals↗

PubMed1986

Isolation and characterization of nerve growth factor from Vipera berus berus (common viper) venom.

Nerve growth factor from Vipera berus berus venom was purified by gel filtration on Sephadex G-100 (superfine), ion-exchange-chromatography on DEAE-Sephadex A-50 and chromatofocusing on PBE 118. The Vipera berus berus venom NGF consists of multiple molecular forms with pls in the interval 9.1-9.7. All isoforms have identical mol. wts approximately 35,000 +/- 3000 (in gel filtration) and 17,000 +/- 2000, 15,000 +/- 2000 (by SDS electrophoresis with beta-mercaptethanol). V. berus berus venom NGF reacted with monoclonal antibodies against Viper lebetina NGF and caused differentiation of pheochromocytoma PC12 cells.

Animals↗

PubMed1990

A comparative study of the biological properties of venoms from snakes of the genus Vipera (true adders)

1. The hemorrhagic, procoagulant, anticoagulant, phosphodiesterase, hyaluronidase, alkaline phosphomonoesterase, 5'-nucleotidase, arginine ester hydrolase, phospholipase A, L-amino acid oxidase and protease activities of 26 samples of venoms of 13 taxa of Vipera were determined and the Sephadex G-75 gel filtration patterns for some of the venoms were also examined. 2. The results indicate the presence of certain common characteristics among the venoms, particularly if V. russelli is excluded from the comparison. The results also support the recently proposed reassignment of V. russelli to a separate genus. 3. The data show that information on venom biological properties can be used for differentiation of venoms of many species of Vipera. Particularly useful for this purpose are the protease, phosphodiesterase, phospholipase A and the procoagulant activities and the Sephadex G-75 gel filtration patterns of the venoms.

Animals↗