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African adders: partial characterization of snake venoms from three Bitis species of medical importance and their neutralization by experimental equine antivenoms.

Paixão-Cavalcante D, Kuniyoshi AK, Portaro FC, da Silva WD, Tambourgi DV - PLoS Negl Trop Dis (2015)

Bottom Line: The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies.Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested.We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms.

View Article: PubMed Central - PubMed

Affiliation: Immunochemistry Laboratory, Butantan Institute, São Paulo, São Paulo, Brazil.

ABSTRACT

Background: An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms.

Methodology/principal findings: The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1-7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested.

Conclusion: These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms.

No MeSH data available.


Related in: MedlinePlus

Biochemical characterization of Bitis ssp venoms.[A] Venoms samples (30 μg) from B. arietans (Ba), B. g. rhinoceros (Br) and B. nasicornis (Bn) snakes were separated by SDS-PAGE (8–16% gel) under non-reducing and reducing conditions and silver stained. [B] Venom samples (10 μg) from Bitis ssp were separated by SDS-PAGE and electrotransfered into nitrocellulose membranes to analyze the presence of oligosaccharide residues. Blots were probed with WGA-HRPO (WGA) or Con A-HRPO (Con A) and the reactions developed with DAB.
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pntd.0003419.g001: Biochemical characterization of Bitis ssp venoms.[A] Venoms samples (30 μg) from B. arietans (Ba), B. g. rhinoceros (Br) and B. nasicornis (Bn) snakes were separated by SDS-PAGE (8–16% gel) under non-reducing and reducing conditions and silver stained. [B] Venom samples (10 μg) from Bitis ssp were separated by SDS-PAGE and electrotransfered into nitrocellulose membranes to analyze the presence of oligosaccharide residues. Blots were probed with WGA-HRPO (WGA) or Con A-HRPO (Con A) and the reactions developed with DAB.

Mentions: All the three Bitis venoms presented different electrophoretic profiles containing bands with molecular weight varying from 10 to 200 kDa (Fig. 1A). Some of these bands are probably in complex or present disulfide bonds inter- or intra-chains as observed by the presence of extra bands of lower molecular weight after reduction (Fig. 1A). All venoms presented some proteins with sugar residues, as determined by the interaction with WGA, which selectively binds to N-acetylneuraminic acid and N-acetylglucosamil residues [24] or Con A, which selectively binds to α-mannopyranosyl and α-glucopyranosyl residues [25] (Fig. 1B). The specificity of the lectin binding was confirmed by the absence of bands on the membranes incubated with lectins in the presence of the specific sugars.


African adders: partial characterization of snake venoms from three Bitis species of medical importance and their neutralization by experimental equine antivenoms.

Paixão-Cavalcante D, Kuniyoshi AK, Portaro FC, da Silva WD, Tambourgi DV - PLoS Negl Trop Dis (2015)

Biochemical characterization of Bitis ssp venoms.[A] Venoms samples (30 μg) from B. arietans (Ba), B. g. rhinoceros (Br) and B. nasicornis (Bn) snakes were separated by SDS-PAGE (8–16% gel) under non-reducing and reducing conditions and silver stained. [B] Venom samples (10 μg) from Bitis ssp were separated by SDS-PAGE and electrotransfered into nitrocellulose membranes to analyze the presence of oligosaccharide residues. Blots were probed with WGA-HRPO (WGA) or Con A-HRPO (Con A) and the reactions developed with DAB.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4340965&req=5

pntd.0003419.g001: Biochemical characterization of Bitis ssp venoms.[A] Venoms samples (30 μg) from B. arietans (Ba), B. g. rhinoceros (Br) and B. nasicornis (Bn) snakes were separated by SDS-PAGE (8–16% gel) under non-reducing and reducing conditions and silver stained. [B] Venom samples (10 μg) from Bitis ssp were separated by SDS-PAGE and electrotransfered into nitrocellulose membranes to analyze the presence of oligosaccharide residues. Blots were probed with WGA-HRPO (WGA) or Con A-HRPO (Con A) and the reactions developed with DAB.
Mentions: All the three Bitis venoms presented different electrophoretic profiles containing bands with molecular weight varying from 10 to 200 kDa (Fig. 1A). Some of these bands are probably in complex or present disulfide bonds inter- or intra-chains as observed by the presence of extra bands of lower molecular weight after reduction (Fig. 1A). All venoms presented some proteins with sugar residues, as determined by the interaction with WGA, which selectively binds to N-acetylneuraminic acid and N-acetylglucosamil residues [24] or Con A, which selectively binds to α-mannopyranosyl and α-glucopyranosyl residues [25] (Fig. 1B). The specificity of the lectin binding was confirmed by the absence of bands on the membranes incubated with lectins in the presence of the specific sugars.

Bottom Line: The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies.Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested.We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms.

View Article: PubMed Central - PubMed

Affiliation: Immunochemistry Laboratory, Butantan Institute, São Paulo, São Paulo, Brazil.

ABSTRACT

Background: An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms.

Methodology/principal findings: The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1-7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested.

Conclusion: These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms.

No MeSH data available.


Related in: MedlinePlus