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Trevisan-Silva D, Cosenza-Contreras M, Oliveira UC, da Rós N, Andrade-Silva D, Menezes MC, Oliveira AK, Rosa JG, Sachetto ATA, Biniossek ML, Pinter N, Santoro ML, Nishiyama-Jr MY, Schilling O, Serrano SMT. Systemic toxicity of snake venom metalloproteinases: Multi-omics analyses of kidney and blood plasma disturbances in a mouse model. Int J Biol Macromol 2023; 253:127279. [PMID: 37806411 DOI: 10.1016/j.ijbiomac.2023.127279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/04/2023] [Accepted: 10/05/2023] [Indexed: 10/10/2023]
Abstract
Snakebite envenomation is classified as a Neglected Tropical Disease. Bothrops jararaca venom induces kidney injury and coagulopathy. HF3, a hemorrhagic metalloproteinase of B. jararaca venom, participates in the envenomation pathogenesis. We evaluated the effects of HF3 in mouse kidney and blood plasma after injection in the thigh muscle, mimicking a snakebite. Transcriptomic analysis showed differential expression of 31 and 137 genes related to kidney pathology after 2 h and 6 h, respectively. However, only subtle changes were observed in kidney proteome, with differential abundance of 15 proteins after 6 h, including kidney injury markers. N-terminomic analysis of kidney proteins showed 420 proteinase-generated peptides compatible with meprin specificity, indicating activation of host proteinases. Plasma analysis revealed differential abundance of 90 and 219 proteins, respectively, after 2 h and 6 h, including coagulation-cascade and complement-system components, and creatine-kinase, whereas a semi-specific search of N-terminal peptides indicated activation of endogenous proteinases. HF3 promoted host reactions, altering the gene expression and the proteolytic profile of kidney tissue, and inducing plasma proteome imbalance driven by changes in abundance and proteolysis. The overall response of the mouse underscores the systemic action of a hemorrhagic toxin that transcends local tissue damage and is related to known venom-induced systemic effects.
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Affiliation(s)
- Dilza Trevisan-Silva
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Miguel Cosenza-Contreras
- Faculty of Medicine, Institute for Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Ursula C Oliveira
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Nancy da Rós
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Débora Andrade-Silva
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Milene C Menezes
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Ana Karina Oliveira
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | | | | | - Martin L Biniossek
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Niko Pinter
- Faculty of Medicine, Institute for Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany
| | | | - Milton Y Nishiyama-Jr
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Oliver Schilling
- Faculty of Medicine, Institute for Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany.
| | - Solange M T Serrano
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil.
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Sachetto ATA, Miyamoto JG, Tashima AK, de Souza AO, Santoro ML. The Bioflavonoids Rutin and Rutin Succinate Neutralize the Toxins of B. jararaca Venom and Inhibit its Lethality. Front Pharmacol 2022; 13:828269. [PMID: 35264963 PMCID: PMC8899467 DOI: 10.3389/fphar.2022.828269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 01/27/2022] [Indexed: 12/12/2022] Open
Abstract
The venom of the Brazilian pit viper Bothrops jararaca (BjV) is a complex mixture of molecules, and snake venom metalloproteinases (SVMP) and serine proteinases (SVSP) are the most abundant protein families found therein. Toxins present in BjV trigger most of the deleterious disturbances in hemostasis observed in snakebites, i.e., thrombocytopenia, hypofibrinogenemia and bleedings. The treatment of patients bitten by snakes still poses challenges and the bioflavonoid rutin has already been shown to improve hemostasis in an experimental model of snakebite envenomation. However, rutin is poorly soluble in water; in this study, it was succinylated to generate its water-soluble form, rutin succinate (RS), which was analyzed comparatively regarding the chemical structure and characteristic features of rutin. Biological activities of rutin and RS were compared on hemostatic parameters, and against toxic activities of crude BjV in vitro. In vivo, C57BL/6 mice were injected i.p. with either BjV alone or pre-incubated with rutin, RS or 1,10-phenanthroline (o-phe, an SVMP inhibitor), and the survival rates and hemostatic parameters were analyzed 48 h after envenomation. RS showed the characteristic activities described for rutin – i.e., antioxidant and inhibitor of protein disulfide isomerase – but also prolonged the clotting time of fibrinogen and plasma in vitro. Differently from rutin, RS inhibited typical proteolytic activities of SVMP, as well as the coagulant activity of BjV. Importantly, both rutin and RS completely abrogated the lethal activity of BjV, in the same degree as o-phe. BjV induced hemorrhages, falls in RBC counts, thrombocytopenia and hypofibrinogenemia in mice. Rutin and RS also improved the recovery of platelet counts and fibrinogen levels, and the development of hemorrhages was totally blocked in mice injected with BjV incubated with RS. In conclusion, RS has anticoagulant properties and is a novel SVMP inhibitor. Rutin and RS showed different mechanisms of action on hemostasis. Only RS inhibited directly BjV biological activities, even though both flavonoids neutralized B. jararaca toxicity in vivo. Our results showed clearly that rutin and RS show a great potential to be used as therapeutic compounds for snakebite envenomation.
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Affiliation(s)
- Ana Teresa Azevedo Sachetto
- Laboratory of Pathophysiology, Institute Butantan, São Paulo, Brazil.,Department of Medical Sciences, School of Medicine, University of São Paulo, São Paulo, Brazil
| | - Jackson Gabriel Miyamoto
- Department of Biochemistry, Escola Paulista de Medicina, Federal University of São Paulo, (EPM/UNIFESP), São Paulo, Brazil
| | - Alexandre Keiji Tashima
- Department of Biochemistry, Escola Paulista de Medicina, Federal University of São Paulo, (EPM/UNIFESP), São Paulo, Brazil
| | - Ana Olívia de Souza
- Laboratory of Development and Innovation, Institute Butantan, São Paulo, Brazil
| | - Marcelo Larami Santoro
- Laboratory of Pathophysiology, Institute Butantan, São Paulo, Brazil.,Department of Medical Sciences, School of Medicine, University of São Paulo, São Paulo, Brazil
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3
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Thomazini CM, Sachetto ATA, de Albuquerque CZ, de Moura Mattaraia VG, de Oliveira AK, Serrano SMDT, Lebrun I, Barbaro KC, Santoro ML. Involvement of von Willebrand factor and botrocetin in the thrombocytopenia induced by Bothrops jararaca snake venom. PLoS Negl Trop Dis 2021; 15:e0009715. [PMID: 34478462 PMCID: PMC8445451 DOI: 10.1371/journal.pntd.0009715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 09/16/2021] [Accepted: 08/06/2021] [Indexed: 12/20/2022] Open
Abstract
Patients bitten by snakes consistently manifest a bleeding tendency, in which thrombocytopenia, consumption coagulopathy, mucous bleeding, and, more rarely, thrombotic microangiopathy, are observed. Von Willebrand factor (VWF) is required for primary hemostasis, and some venom proteins, such as botrocetin (a C-type lectin-like protein) and snake venom metalloproteinases (SVMP), disturb the normal interaction between platelets and VWF, possibly contributing to snakebite-induced bleedings. To understand the relationship among plasma VWF, platelets, botrocetin and SVMP from Bothrops jararaca snake venom (BjV) in the development of thrombocytopenia, we used (a) Wistar rats injected s.c. with BjV preincubated with anti-botrocetin antibodies (ABA) and/or Na2-EDTA (a SVMP inhibitor), and (b) VWF knockout mice (Vwf-/-) injected with BjV. Under all conditions, BjV induced a rapid and intense thrombocytopenia. In rats, BjV alone reduced the levels of VWF:Ag, VWF:CB, high molecular weight multimers of VWF, ADAMTS13 activity, and factor VIII. Moreover, VWF:Ag levels in rats that received BjV preincubated with Na2-EDTA and/or ABA tended to recover faster. In mice, BjV caused thrombocytopenia in both Vwf-/- and C57BL/6 (background control) strains, and VWF:Ag levels tended to decrease in C57BL/6, demonstrating that thrombocytopenia was independent of the presence of plasma VWF. These findings showed that botrocetin present in BjV failed to affect the extent or the time course of thrombocytopenia induced by envenomation, but it contributed to decrease the levels and function of plasma VWF. Thus, VWF alterations during B. jararaca envenomation are an ancillary event, and not the main mechanism leading to decreased platelet counts.
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Affiliation(s)
- Camila Martos Thomazini
- Laboratório de Fisiopatologia, Instituto Butantan, São Paulo-SP, Brazil
- Programa de Pós-Graduação em Clínica Médica, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo-SP, Brazil
| | - Ana Teresa Azevedo Sachetto
- Laboratório de Fisiopatologia, Instituto Butantan, São Paulo-SP, Brazil
- Programa de Pós-Graduação em Clínica Médica, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo-SP, Brazil
| | | | | | - Ana Karina de Oliveira
- Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo-SP, Brazil
| | - Solange Maria de Toledo Serrano
- Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo-SP, Brazil
| | - Ivo Lebrun
- Laboratório de Bioquímica e Biofísica, Instituto Butantan, São Paulo-SP, Brazil
| | | | - Marcelo Larami Santoro
- Laboratório de Fisiopatologia, Instituto Butantan, São Paulo-SP, Brazil
- Programa de Pós-Graduação em Clínica Médica, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo-SP, Brazil
- * E-mail: ,
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Freitas-de-Sousa LA, Nachtigall PG, Portes-Junior JA, Holding ML, Nystrom GS, Ellsworth SA, Guimarães NC, Tioyama E, Ortiz F, Silva BR, Kunz TS, Junqueira-de-Azevedo ILM, Grazziotin FG, Rokyta DR, Moura-da-Silva AM. Size Matters: An Evaluation of the Molecular Basis of Ontogenetic Modifications in the Composition of Bothrops jararacussu Snake Venom. Toxins (Basel) 2020; 12:toxins12120791. [PMID: 33322460 PMCID: PMC7763748 DOI: 10.3390/toxins12120791] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022] Open
Abstract
Ontogenetic changes in venom composition have been described in Bothrops snakes, but only a few studies have attempted to identify the targeted paralogues or the molecular mechanisms involved in modifications of gene expression during ontogeny. In this study, we decoded B. jararacussu venom gland transcripts from six specimens of varying sizes and analyzed the variability in the composition of independent venom proteomes from 19 individuals. We identified 125 distinct putative toxin transcripts, and of these, 73 were detected in venom proteomes and only 10 were involved in the ontogenetic changes. Ontogenetic variability was linearly related to snake size and did not correspond to the maturation of the reproductive stage. Changes in the transcriptome were highly predictive of changes in the venom proteome. The basic myotoxic phospholipases A2 (PLA2s) were the most abundant components in larger snakes, while in venoms from smaller snakes, PIII-class SVMPs were the major components. The snake venom metalloproteinases (SVMPs) identified corresponded to novel sequences and conferred higher pro-coagulant and hemorrhagic functions to the venom of small snakes. The mechanisms modulating venom variability are predominantly related to transcriptional events and may consist of an advantage of higher hematotoxicity and more efficient predatory function in the venom from small snakes.
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Affiliation(s)
- Luciana A. Freitas-de-Sousa
- Programa de Pós-Graduação em Ciências-Toxinologia, Laboratório de Imunopatologia, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (N.C.G.); (E.T.)
- Correspondence: (L.A.F.-d.-S.); (A.M.M.-d.-S.); Tel.: +55-11-2627-9779 (A.M.M.-d.-S.)
| | - Pedro G. Nachtigall
- Laboratório Especial de Toxinologia Aplicada, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (P.G.N.); (I.L.M.J.-d.-A.)
| | - José A. Portes-Junior
- Laboratório de Coleções Zoológicas, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (J.A.P.-J.); (F.O.); (B.R.S.); (T.S.K.); (F.G.G.)
| | - Matthew L. Holding
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA; (M.L.H.); (G.S.N.); (S.A.E.); (D.R.R.)
| | - Gunnar S. Nystrom
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA; (M.L.H.); (G.S.N.); (S.A.E.); (D.R.R.)
| | - Schyler A. Ellsworth
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA; (M.L.H.); (G.S.N.); (S.A.E.); (D.R.R.)
| | - Noranathan C. Guimarães
- Programa de Pós-Graduação em Ciências-Toxinologia, Laboratório de Imunopatologia, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (N.C.G.); (E.T.)
| | - Emilly Tioyama
- Programa de Pós-Graduação em Ciências-Toxinologia, Laboratório de Imunopatologia, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (N.C.G.); (E.T.)
| | - Flora Ortiz
- Laboratório de Coleções Zoológicas, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (J.A.P.-J.); (F.O.); (B.R.S.); (T.S.K.); (F.G.G.)
| | - Bruno R. Silva
- Laboratório de Coleções Zoológicas, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (J.A.P.-J.); (F.O.); (B.R.S.); (T.S.K.); (F.G.G.)
| | - Tobias S. Kunz
- Laboratório de Coleções Zoológicas, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (J.A.P.-J.); (F.O.); (B.R.S.); (T.S.K.); (F.G.G.)
| | | | - Felipe G. Grazziotin
- Laboratório de Coleções Zoológicas, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (J.A.P.-J.); (F.O.); (B.R.S.); (T.S.K.); (F.G.G.)
| | - Darin R. Rokyta
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA; (M.L.H.); (G.S.N.); (S.A.E.); (D.R.R.)
| | - Ana M. Moura-da-Silva
- Programa de Pós-Graduação em Ciências-Toxinologia, Laboratório de Imunopatologia, Instituto Butantan, 05503-900 São Paulo, SP, Brazil; (N.C.G.); (E.T.)
- Instituto de Pesquisa Clínica Carlos Borborema, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, 69040-000 Manaus, AM, Brazil
- Correspondence: (L.A.F.-d.-S.); (A.M.M.-d.-S.); Tel.: +55-11-2627-9779 (A.M.M.-d.-S.)
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Sachetto ATA, Jensen JR, Santoro ML. Liver gene regulation of hemostasis-related factors is altered by experimental snake envenomation in mice. PLoS Negl Trop Dis 2020; 14:e0008379. [PMID: 32479494 PMCID: PMC7289449 DOI: 10.1371/journal.pntd.0008379] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 06/11/2020] [Accepted: 05/09/2020] [Indexed: 12/30/2022] Open
Abstract
Few studies have addressed gene expression of hemostasis-related factors during acute thrombo-hemorrhagic diseases. Bites by the lanced-headed viper Bothrops jaracaca induce rapid hemostatic disturbances in victims, leading to systemic bleedings, thrombocytopenia and consumption coagulopathy. Although circulating levels of coagulation factors recover rapidly after administration of specific antivenom therapy, it is unclear if B. jararaca venom (BjV) upregulates the mRNA synthesis of hepatic hemostasis-related factors, or if the recovery occurs under basal conditions after the neutralization of venom components by antivenom. Thus, we aimed to investigate if BjV regulates gene expression of important hemostasis-related factors synthetized by the liver. On that account, Swiss mice were injected with saline or BjV (1.6 mg/kg b.w, s.c.), and after 3, 6 and 24 h blood samples and liver fragments were collected to analyze mRNA expression by real-time qPCR. Increased gene expression of fibrinogen chains, haptoglobin and STAT3 was observed during envenomation, particularly at 3 and 6 h. At 24h, mRNA levels of F10 were raised, while those of Serpinc1, Proc and Adamts13 were diminished. Surprisingly, F3 mRNA levels were steadily decreased at 3 h. Gene expression of Thpo, F7, F5 Tfpi, Mug1 was unaltered. mRNA levels of Vwf, P4hb, F8, F2, Plg, and Serpinf2 were minimally altered, but showed important associations with Nfkb1 gene expression. In conclusion, snakebite envenomation upregulates hepatic mRNA synthesis particularly of fibrinogen chains, and acute-phase markers. This response explains the fast recovery of fibrinogen levels after antivenom administration to patients bitten by B. jararaca snakes.
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Affiliation(s)
- Ana Teresa Azevedo Sachetto
- Laboratory of Pathophysiology, Butantan Institute, São Paulo, São Paulo, Brazil
- Department of Medical Sciences, School of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
| | - José Ricardo Jensen
- Laboratory of Immunogenetics, Butantan Institute, São Paulo, São Paulo, Brazil
| | - Marcelo Larami Santoro
- Laboratory of Pathophysiology, Butantan Institute, São Paulo, São Paulo, Brazil
- Department of Medical Sciences, School of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
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Teixeira C, Fernandes CM, Leiguez E, Chudzinski-Tavassi AM. Inflammation Induced by Platelet-Activating Viperid Snake Venoms: Perspectives on Thromboinflammation. Front Immunol 2019; 10:2082. [PMID: 31572356 PMCID: PMC6737392 DOI: 10.3389/fimmu.2019.02082] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/16/2019] [Indexed: 01/01/2023] Open
Abstract
Envenomation by viperid snakes is characterized by systemic thrombotic syndrome and prominent local inflammation. To date, the mechanisms underlying inflammation and blood coagulation induced by Viperidae venoms have been viewed as distinct processes. However, studies on the mechanisms involved in these processes have revealed several factors and signaling molecules that simultaneously act in both the innate immune and hemostatic systems, suggesting an overlap between both systems during viper envenomation. Moreover, distinct classes of venom toxins involved in these effects have also been identified. However, the interplay between inflammation and hemostatic alterations, referred as to thromboinflammation, has never been addressed in the investigation of viper envenomation. Considering that platelets are important targets of viper snake venoms and are critical for the process of thromboinflammation, in this review, we summarize the inflammatory effects and mechanisms induced by viper snake venoms, particularly from the Bothrops genus, which strongly activate platelet functions and highlight selected venom components (metalloproteases and C-type lectins) that both stimulate platelet functions and exhibit pro-inflammatory activities, thus providing insights into the possible role(s) of thromboinflammation in viper envenomation.
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Affiliation(s)
- Catarina Teixeira
- Laboratory of Pharmacology, Butantan Institute, São Paulo, Brazil.,Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil
| | - Cristina Maria Fernandes
- Laboratory of Pharmacology, Butantan Institute, São Paulo, Brazil.,Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil
| | - Elbio Leiguez
- Laboratory of Pharmacology, Butantan Institute, São Paulo, Brazil.,Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil
| | - Ana Marisa Chudzinski-Tavassi
- Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil.,Laboratory of Molecular Biology, Butantan Institute, São Paulo, Brazil
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Elevated plasma levels of hepatocyte growth factor in rats experimentally envenomated with Bothrops jararaca venom: Role of snake venom metalloproteases. Toxicon 2019; 162:9-14. [PMID: 30849454 DOI: 10.1016/j.toxicon.2019.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 02/28/2019] [Accepted: 03/03/2019] [Indexed: 01/06/2023]
Abstract
The hepatocyte growth factor (HGF)/c-met pathway, which mainly consists of HGF activator (HGFA) and its substrate HGF, protects various types of cells via anti-apoptotic and anti-inflammatory signals. Thrombin is the main physiological activator of such plasmatic pathway, and increased plasma concentrations of HGF have been considered as a molecular marker for some pathological conditions, such as disseminated intravascular coagulation. Since thrombin generation is often linked to tissue injury, and these events are common during snake venom-induced consumption coagulopathies (VICC), our goals were to examine whether Bothrops jararaca venom (Bjv), which induces VICC in vivo: (i) activates the HGF/c-met pathway in vivo and (ii) cleaves zymogen forms of HGFA and HGF (proHGFA and proHGF, respectively) in vitro. Two experimental groups (n = 6, each) of male adult Wistar rats were subcutaneously injected with 500 μL of 0.9% NaCl solution (control) or sub-lethal doses (1.6 mg/kg) of Bjv. Three hours after envenomation, whole blood samples were collected from the carotid arteries to evaluate relevant coagulation parameters using rotational thromboelastometry and fibrinogen level (colorimetric assay). Additionally, the plasma concentration of HGF was assayed (ELISA). Thromboelastometric assays showed that blood clotting and fibrin polymerization were severely impaired 3 h after Bjv injection. Total plasma HGF concentrations were almost 6-fold higher in the Bjv-injected group (410.0 ± 91) compared with control values (68 ± 18 pg/mL, p < 0.05). Western blotting assay showed that Bjv processed proHGFA and proHGF, generating bands resembling those generated by thrombin and kallikrein, respectively. In contrast to the serine protease inhibitor 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF), the metalloprotease inhibitor ethylenediaminetetraacetic acid disodium salt (Na2-EDTA) strongly reduced the ability of Bjv to process proHGFA and generated one active band similar to that of thrombin. Since Bjv contains prothrombin and factor X activators, increased intravascular thrombin formation might partly explain the increased HGF levels after bothropic envenomation. In conclusion, these findings suggest that snake venom metalloproteases may be determinant for elevation of plasma levels of HGF in rats experimentally envenomated with Bjv.
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Thomazini CM, Soares RDPS, da Rocha TRF, Sachetto ATA, Santoro ML. Optimization of von Willebrand factor multimer analysis in vertical mini-gel electrophoresis systems: A rapid procedure. Thromb Res 2019; 175:76-83. [PMID: 30731387 DOI: 10.1016/j.thromres.2019.01.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/15/2019] [Accepted: 01/28/2019] [Indexed: 12/20/2022]
Abstract
Von Willebrand disease (VWD) is a common cause of bleeding worldwide. Analysis of von Willebrand factor (VWF) multimer distribution (VWF:MD) is essential to properly classify and treat different types of VWD, and it is performed using a SDS agarose gel electrophoresis followed by Western blotting, a handmade technique that demands days to be completed and requires skillful execution. Aiming both to facilitate gel production and to shorten the preparation time, we developed an uncomplicated technique to provide agility in the analysis of VWF:MD, so that it can be easily accomplished in the routine practice of hemostasis laboratories. On that account, we used a commercial vertical mini-gel electrophoresis system for SDS-PAGE and a semi-dry transfer system, which allowed us to analyze VWF:MD of various samples in a period shorter than 12 h. This technique differentiated VWF:MD in human and animal plasmas under normal, congenital and acquired (experimental envenomation by Bothrops jararaca snake) conditions. This optimized method is cheap, rapid, reproducible, easy to be performed, and uses electrophoresis and Western blotting systems available in most laboratories. All these advantages encourage hemostasis professionals to use it in their routine practices. In order to facilitate the setup and accomplishment of the whole procedure step by step, videos were appended to the article.
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Affiliation(s)
- Camila Martos Thomazini
- Instituto Butantan, Laboratório de Fisiopatologia, São Paulo, SP, Brazil; Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Tania Rubia Flores da Rocha
- Fundação Pró-Sangue, Hemocentro de São Paulo, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ana Teresa Azevedo Sachetto
- Instituto Butantan, Laboratório de Fisiopatologia, São Paulo, SP, Brazil; Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marcelo Larami Santoro
- Instituto Butantan, Laboratório de Fisiopatologia, São Paulo, SP, Brazil; Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
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9
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Rosa JG, de Albuquerque CZ, Mattaraia VGDM, Santoro ML. Comparative study of platelet aggregation and secretion induced by Bothrops jararaca snake venom and thrombin. Toxicon 2019; 159:50-60. [PMID: 30677414 DOI: 10.1016/j.toxicon.2019.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/04/2019] [Accepted: 01/10/2019] [Indexed: 12/28/2022]
Abstract
Victims of Bothrops jararaca snakebites manifest bleedings, blood incoagulability, platelet dysfunction, and thrombocytopenia, and the latter has been directly implicated in the genesis of hemorrhagic diathesis. We addressed herein the direct effects of B. jararaca venom (BjV) on ex vivo platelet aggregation and granule secretion in washed human and mouse platelets. BjV directly aggregated platelets, but the extent of platelet aggregation was lower in human than mouse platelets. On the other hand, BjV (24.4 μg/mL) and thrombin (0.1 U/mL) induced a similar extent of ATP and platelet factor 4 (PF4) secretion in both species. BjV-induced platelet aggregation was independent of the platelet dense body content, as in pearl mouse (Ap3b1-/-) platelets, whose dense bodies are deficient in adenine nucleotides and serotonin, the extent of platelet aggregation was superior to that induced in BALB/c or C57BL/6 mice. BjV-induced β-hexosaminidase secretion in human platelets was less intense than that evoked by thrombin, and the contrary was observed in mouse platelets. Irreversible inactivation of platelet cyclooxygenase 1 by acetylsalicylic acid did not reduce BjV-induced platelet aggregation. BjV exerted no cytotoxic activity in human and mouse platelets, as evaluated by lactate dehydrogenase loss. Eptifibatide, which inhibits the binding of fibrinogen to platelet glycoprotein complex GPIIb-IIIa, differently blocked BjV-induced platelet aggregation in mice and humans. BjV-induced platelet aggregation did not depend on snake venom serine proteinases nor metalloproteinases in mice, whilst serine proteinases were rather important for platelet aggregation in humans. Our results show that BjV induces direct activation, aggregation, and secretion in human and mouse platelets, but it exerts diverse responses in them, which should be considered in comparative studies to understand pathophysiological events during Bothrops envenomation.
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Affiliation(s)
- Jaqueline Gomes Rosa
- Instituto Butantan, Laboratório de Fisiopatologia, Av. Dr. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil; Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | | | - Marcelo Larami Santoro
- Instituto Butantan, Laboratório de Fisiopatologia, Av. Dr. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil; Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
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Araujo RT, Corrêa-Netto C, Brazil-Más L, Silveira CRF, Fernandes I, Zingali RB. Can anti-bothropstoxin-I antibodies discriminate between Bothrops jararaca and Bothrops jararacussu venoms? J Venom Anim Toxins Incl Trop Dis 2017; 23:12. [PMID: 28293253 PMCID: PMC5346246 DOI: 10.1186/s40409-017-0105-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 02/24/2017] [Indexed: 11/25/2022] Open
Abstract
Background Snakes of the genus Bothrops, popularly known as pit vipers, are responsible for most cases of snakebite in Brazil. Within this genus, Bothrops jararacussu and B. jararaca deserve special attention due to the severity of their bites and for inhabiting densely populated areas. Regarding the treatment of snakebites by Bothrops jararacussu, questions have been raised about the effectiveness of the specific bothropic antivenom in neutralizing myotoxic effects; however, there are no accurate data for humans. Thus, the development of a differential diagnostic kit for this species would be of great interest because it provides, for healthcare professionals, a tool that would allow us to determine whether the accident was caused by B. jararacussu or other species of the genus. It would also make it possible to evaluate the specificity of the treatment and to provide data for epidemiological studies. Methods First, we produced a species-specific polyclonal antibody – a potential biomarker of Bothrops jararacussu venom – against bothropstoxin-I (BthTx-I), which is also found in smaller quantities in the venoms of B. jararaca from southern Brazil. Results Polyclonal antibodies against bothropstoxin-I could be separated into several species-specific immunoglobulins. Then, aiming to develop a system of safe and standardized immunoassay, we produced monoclonal antibodies. Seven hybridomas were obtained. Five of them were specific to the venom of B. jararacussu and two recognized the venom of B. jararaca from the southeastern population. The use of monoclonal antibodies also made it possible to differentiate B. jararacussu from B. jararaca venom obtained from the southern population. Analyzing the reactivity of monoclonal antibodies against other bothropic venoms, we found mAb Bt-3 to be more specific than others for B. jararacussu venom. Conclusions These results show the potential of BthTx-I for producing monoclonal antibodies that differentiate between B. jararacussu and other Bothrops species venoms.
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Affiliation(s)
- Ricardo Teixeira Araujo
- Laboratório de Hemostase e Venenos, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ Brasil.,Instituto Vital Brazil, Niterói, RJ Brasil
| | - Carlos Corrêa-Netto
- Laboratório de Hemostase e Venenos, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ Brasil.,Instituto Vital Brazil, Niterói, RJ Brasil
| | | | | | | | - Russolina Benedeta Zingali
- Laboratório de Hemostase e Venenos, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ Brasil
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Köppel C, Martens F. Clinical Experience in the Therapy of Bites from Exotic Snakes in Berlin. Hum Exp Toxicol 2016; 11:549-52. [PMID: 1361148 DOI: 10.1177/096032719201100619] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Since there are nearly no indigenous poisonous snakes in Germany, snake bites by poisonous snakes are rare. Most serious snake bites reported to poison information centres or treated at hospitals are caused by exotic snakes that are kept in private households. Only few types of antivenom are stored in emergency depots in Germany including polyvalent antivenoms from commercial sources. Since experience with the treatment of poisonous snake bites is limited, the records of the Intensive Care Unit and the Poison Information Centre of the Universitätsklinikum Rudolf Virchow from 1980-1991 were evaluated. During this period, 51 snake bites were reported. Eleven patients who had been bitten by exotic poisonous snakes were treated in intensive care. In eight of the cases, ethanol (blood levels on admission 1.2-4.2 g-1) had played an important role in the cause of the bite. A moderate to severe local inflammation at the site of the bite followed by oedema and necrosis was typical. One patient developed respiratory failure, probably because of the neurotoxic effects of the snake venom and a compartment syndrome necessitating fasciotomy. Haemolysis was observed in four patients and coagulopathy in six patients. All patients received polyvalent antivenom within 2-12 h of the snake bite. Despite serious coagulopathy in two of the patients and respiratory arrest in one, all survived without sequelae.
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Affiliation(s)
- C Köppel
- Medical Intensive Care Unit, Universitätsklinikum Rudolf Virchow, Freie Universität Berlin, Germany
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12
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Abstract
Controlling perioperative bleeding is of critical importance to minimize hemorrhaging and fatality. Patients on anticoagulant therapy such as heparin have diminished clotting potential and are at risk for hemorrhaging. Here we describe a self-assembling nanofibrous peptide hydrogel (termed SLac) that on its own can act as a physical barrier to blood loss. SLac was loaded with snake-venom derived Batroxobin (50 μg/mL) yielding a drug-loaded hydrogel (SB50). SB50 was potentiated to enhance clotting even in the presence of heparin. In vitro evaluation of fibrin and whole blood clotting helped identify appropriate concentrations for hemostasis in vivo. Batroxobin-loaded hydrogels rapidly (within 20s) stop bleeding in both normal and heparin-treated rats in a lateral liver incision model. Compared to standard of care, Gelfoam, and investigational hemostats such as Puramatrix, only SB50 showed rapid liver incision hemostasis post surgical application. This snake venom-loaded peptide hydrogel can be applied via syringe and conforms to the wound site resulting in hemostasis. This demonstrates a facile method for surgical hemostasis even in the presence of anticoagulant therapies.
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Affiliation(s)
- Vivek A Kumar
- Departments of Chemistry and Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77030, United States
| | - Navindee C Wickremasinghe
- Departments of Chemistry and Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77030, United States
| | - Siyu Shi
- Departments of Chemistry and Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77030, United States
| | - Jeffrey D Hartgerink
- Departments of Chemistry and Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77030, United States
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Senise LV, Yamashita KM, Santoro ML. Bothrops jararaca envenomation: Pathogenesis of hemostatic disturbances and intravascular hemolysis. Exp Biol Med (Maywood) 2015; 240:1528-36. [PMID: 26080462 DOI: 10.1177/1535370215590818] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 05/11/2015] [Indexed: 12/15/2022] Open
Abstract
To attain fully functional biological activity, vitamin-K dependent coagulation factors (VKDCF) are γ-carboxylated prior to secretion from liver. Warfarin impairs the γ-carboxylation, and consequently their physiological function. Bothrops jararaca snake venom (BjV) contains several activators of blood coagulation, especially procoagulant enzymes (prothrombin and factor X activators) and thrombin-like enzymes. In order to clarify the relative contribution of prothrombin and factor X activators to the hemostatic disturbances occurring during experimental B. jararaca envenomation, warfarin was used to deplete VKDCF, prior to BjV administration. Male Wistar rats were pretreated with saline (Sal) or warfarin (War) and inoculated subsequently with BjV or saline, thus forming four groups: Sal + Sal (negative control), Sal + BjV (positive control), War + Sal (warfarinization control), and War + BjV. Three hours after inoculation, prothrombin and factor X levels fell 40% and 50%, respectively; levels of both factors decreased more than 97% in the War + Sal and War + BjV groups. Platelet counts dropped 93% and 76% in Sal + BjV and War + BjV, respectively, and plasma fibrinogen levels decreased 86% exclusively in Sal + BjV. After 6 and 24 h, platelet counts and fibrinogen levels increased progressively. A dramatic augmentation in plasma hemoglobin levels and the presence of schizocytes and microcytes in the Sal + BjV group indicated the development of intravascular hemolysis, which was prevented by warfarin pretreatment. Our findings show that intravascular thrombin generation has the foremost role in the pathogenesis of coagulopathy and intravascular hemolysis, but not in the development of thrombocytopenia, in B. jararaca envenomation in rats; in addition, fibrinogenases (metalloproteinases) may contribute to coagulopathy more than thrombin-like enzymes.
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Affiliation(s)
- Luana V Senise
- Laboratory of Pathophysiology, Institute Butantan, São Paulo 05503-900, Brazil Department of Physiology, Biosciences Institute, University of São Paulo, São Paulo 05508-900, Brazil
| | - Karine M Yamashita
- Laboratory of Pathophysiology, Institute Butantan, São Paulo 05503-900, Brazil Department of Clinical Medicine, School of Medicine, University of São Paulo, São Paulo 05508-900, Brazil
| | - Marcelo L Santoro
- Laboratory of Pathophysiology, Institute Butantan, São Paulo 05503-900, Brazil Department of Clinical Medicine, School of Medicine, University of São Paulo, São Paulo 05508-900, Brazil
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Yamashita KM, Alves AF, Barbaro KC, Santoro ML. Bothrops jararaca venom metalloproteinases are essential for coagulopathy and increase plasma tissue factor levels during envenomation. PLoS Negl Trop Dis 2014; 8:e2814. [PMID: 24831016 PMCID: PMC4022520 DOI: 10.1371/journal.pntd.0002814] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 03/10/2014] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND/AIMS Bleeding tendency, coagulopathy and platelet disorders are recurrent manifestations in snakebites occurring worldwide. We reasoned that by damaging tissues and/or activating cells at the site of the bite and systemically, snake venom toxins might release or decrypt tissue factor (TF), resulting in activation of blood coagulation and aggravation of the bleeding tendency. Thus, we addressed (a) whether TF and protein disulfide isomerase (PDI), an oxireductase involved in TF encryption/decryption, were altered in experimental snake envenomation; (b) the involvement and significance of snake venom metalloproteinases (SVMP) and serine proteinases (SVSP) to hemostatic disturbances. METHODS/PRINCIPAL FINDINGS Crude Bothrops jararaca venom (BjV) was preincubated with Na2-EDTA or AEBSF, which are inhibitors of SVMP and SVSP, respectively, and injected subcutaneously or intravenously into rats to analyze the contribution of local lesion to the development of hemostatic disturbances. Samples of blood, lung and skin were collected and analyzed at 3 and 6 h. Platelet counts were markedly diminished in rats, and neither Na2-EDTA nor AEBSF could effectively abrogate this fall. However, Na2-EDTA markedly reduced plasma fibrinogen consumption and hemorrhage at the site of BjV inoculation. Na2-EDTA also abolished the marked elevation in TF levels in plasma at 3 and 6 h, by both administration routes. Moreover, increased TF activity was also noticed in lung and skin tissue samples at 6 h. However, factor VII levels did not decrease over time. PDI expression in skin was normal at 3 h, and downregulated at 6 h in all groups treated with BjV. CONCLUSIONS SVMP induce coagulopathy, hemorrhage and increased TF levels in plasma, but neither SVMP nor SVSP are directly involved in thrombocytopenia. High levels of TF in plasma and TF decryption occur during snake envenomation, like true disseminated intravascular coagulation syndrome, and might be implicated in engendering bleeding manifestations in severely-envenomed patients.
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Affiliation(s)
- Karine M. Yamashita
- Laboratory of Pathophysiology, Institute Butantan, São Paulo, São Paulo, Brazil
- Department of Clinical Medicine, School of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
| | - André F. Alves
- Laboratory of Pathophysiology, Institute Butantan, São Paulo, São Paulo, Brazil
| | - Katia C. Barbaro
- Immunopathology, Institute Butantan, São Paulo, São Paulo, Brazil
| | - Marcelo L. Santoro
- Laboratory of Pathophysiology, Institute Butantan, São Paulo, São Paulo, Brazil
- Department of Clinical Medicine, School of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
- * E-mail: ,
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15
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Gao JF, Wang J, He Y, Qu YF, Lin LH, Ma XM, Ji X. Proteomic and biochemical analyses of short-tailed pit viper (Gloydius brevicaudus) venom: age-related variation and composition-activity correlation. J Proteomics 2014; 105:307-22. [PMID: 24487038 DOI: 10.1016/j.jprot.2014.01.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 01/11/2014] [Accepted: 01/15/2014] [Indexed: 10/25/2022]
Abstract
UNLABELLED We conducted an in-depth analysis of the proteomic and biochemical profiles of the venom of neonate and adult short-tailed pit vipers (Gloydius brevicaudus). Identified proteins were assigned to a few main toxin families. Disintegrin, phospholipase A2 (PLA2), serine proteinase, cysteine-rich secretory protein, C-type lectin-like protein, l-amino acid oxidase and snake venom metalloproteinase (SVMP) were detected in both venoms, while 5'-nucleotidase was detected only in the adult venom. SVMP was the predominant protein family in both venoms (neonate: 65.7%; adult: 64.4%), followed by PLA2 (neonate: 13.4%; adult: 25.0%). Antivenomic analysis revealed that commercial G. brevicaudus antivenom almost neutralized the chromatographic peaks with medium and high molecular masses in both venoms, but did not completely recognize peaks with low molecular mass. Toxicological and enzymatic activities show remarkable age-related variation in G. brevicaudus venom, probably resulting from variation in venom composition. Our data demonstrate age-related variation across venomics, antivenomics and biochemical profiles of G. brevicaudus venom, and have implications for the management of G. brevicaudus bites, including improving antivenom preparation by combining both venoms. BIOLOGICAL SIGNIFICANCE This study investigates the composition and biochemical activity of neonate and adult Gloydius brevicaudus venoms. We found remarkable age-related variation in venom biological activity, likely the result of variation in venom composition. Antivenomics analysis was used to explore difference in neonate and adult G. brevicaudus venoms. Our findings have implications for the diagnosis and clinical management of G. brevicaudus bites, and the design of venom mixtures that will increase the efficacy of commercial antivenom. This article is part of a Special Issue entitled: Proteomics of non-model organisms.
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Affiliation(s)
- Jian-Fang Gao
- Hangzhou Key Laboratory for Animal Adaptation and Evolution, School of Life Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Jin Wang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, Jiangsu, China
| | - Ying He
- Hangzhou Key Laboratory for Animal Adaptation and Evolution, School of Life Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Yan-Fu Qu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, Jiangsu, China
| | - Long-Hui Lin
- Hangzhou Key Laboratory for Animal Adaptation and Evolution, School of Life Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Xiao-Mei Ma
- Hangzhou Key Laboratory for Animal Adaptation and Evolution, School of Life Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Xiang Ji
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, Jiangsu, China.
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da Silva IRF, Lorenzetti R, Rennó AL, Baldissera L, Zelanis A, Serrano SMDT, Hyslop S. BJ-PI2, A non-hemorrhagic metalloproteinase from Bothrops jararaca snake venom. Biochim Biophys Acta Gen Subj 2012; 1820:1809-21. [DOI: 10.1016/j.bbagen.2012.07.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 07/07/2012] [Accepted: 07/25/2012] [Indexed: 11/25/2022]
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17
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Luna KPO, da Silva MB, Pereira VRA. Clinical and immunological aspects of envenomations by Bothrops snakes. J Venom Anim Toxins Incl Trop Dis 2011. [DOI: 10.1590/s1678-91992011000200003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- KPO Luna
- University of Paraíba, Brazil; Federal University of Pernambuco, Brazil
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18
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Comparative analysis of newborn and adult Bothrops jararaca snake venoms. Toxicon 2010; 56:1443-58. [DOI: 10.1016/j.toxicon.2010.08.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 08/24/2010] [Accepted: 08/26/2010] [Indexed: 02/08/2023]
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Santoro ML, Sano-Martins IS, Chamone DAF. In Vivo Platelet Activation Induced byBothrops jararacaVenom in Rabbits. Platelets 2009; 5:162-70. [DOI: 10.3109/09537109409005530] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Santoro ML, Sano-Martins IS, Fan HW, Cardoso JL, Theakston RDG, Warrell DA. Haematological evaluation of patients bitten by the jararaca, Bothrops jararaca, in Brazil. Toxicon 2008; 51:1440-8. [DOI: 10.1016/j.toxicon.2008.03.018] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 03/18/2008] [Accepted: 03/19/2008] [Indexed: 11/25/2022]
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Berger M, Pinto AF, Guimarães JA. Purification and functional characterization of bothrojaractivase, a prothrombin-activating metalloproteinase isolated from Bothrops jararaca snake venom. Toxicon 2008; 51:488-501. [DOI: 10.1016/j.toxicon.2007.09.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2007] [Revised: 09/01/2007] [Accepted: 09/25/2007] [Indexed: 11/28/2022]
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Fernandes RS, Assafim M, Arruda EZ, Melo PA, Zingali RB, Monteiro RQ. Suramin counteracts the haemostatic disturbances produced by Bothrops jararaca snake venom. Toxicon 2007; 49:931-8. [PMID: 17316730 DOI: 10.1016/j.toxicon.2007.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 12/24/2006] [Accepted: 01/11/2007] [Indexed: 11/25/2022]
Abstract
Snakebite accidents produced by Bothrops jararaca typically results in haemostatic changes including pro- and anticoagulant disturbs as well as interference with platelets. Suramin is a hexasulfonated naphthylurea derivative that was recently characterized as a thrombin inhibitor (Monteiro et al., 2004. Suramin interaction with human alpha-thrombin: inhibitory effects and binding studies. Int. J. Biochem. Cell Biol. 36(10), 2077-2085). Here, we evaluated the ability of suramin to counteract some of the haemostatic disturbs produced by B. jararaca venom. In vitro assays showed that suramin inhibited venom-induced hydrolysis of a number of synthetic substrates: S-2238, S-2266, S-2302 and S-2288, being this ability more prominent towards the thrombin substrate S-2238 (IC(50)=4.3 microM). It was also observed that suramin impaired the fibrinogen clotting induced by B. jararaca venom (IC(50)=124 microM). Accordingly, increasing concentrations of suramin progressively delayed venom-induced plasma clotting, with complete inhibition attained at concentrations above 1.0 mM. In addition, the platelet-aggregating properties of B. jararaca venom were inhibited by suramin in a dose-dependent fashion (IC(50)=127 microM). Suramin showed no effect in the in vivo hemorrhagic effect of venom in mouse skin. The in vivo effect of suramin was further tested using a previously established venous thrombosis model in rats induced by intravenous administration of B. jararaca venom combined with stasis. Venom doses of 100 microg/kg produced 100% of thrombus incidence (10.6+/-1.7 mg). On the other hand, previous administration of suramin partially inhibited thrombus formation. Thus, 12.5 or 25 mg/kg of suramin decreased thrombus weight by 24% and 40%, respectively. Remarkably, co-administration of 3 microL/kg of antibothropic serum (which has no effect on thrombus formation) and 12.5 mg/kg of suramin decreased thrombus weight by 75%, suggesting a synergic effect. Altogether, we demonstrate here that suramin inhibits in vitro and in vivo haemostatic changes caused by B. jararaca venom. At this point, this drug could be of potential interest for association with conventional antiserum therapy.
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Affiliation(s)
- Renato S Fernandes
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Cidado Universitária, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro, RJ, Brazil
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25
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Mirshafiey A. Venom therapy in multiple sclerosis. Neuropharmacology 2007; 53:353-61. [PMID: 17583756 DOI: 10.1016/j.neuropharm.2007.05.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Revised: 04/30/2007] [Accepted: 05/03/2007] [Indexed: 11/16/2022]
Abstract
To date many people with multiple sclerosis (MS) seek complementary and alternative medicines (CAM) to treat their symptoms as an adjunct to conventionally used therapies. Among the common CAM therapies, there is a renewed interest in the therapeutic potential of venoms in MS. The efficacy of this therapeutic method remains unclear. However, venom-based therapy using bee, snakes and scorpions venom and/or sea anemones toxin has been recently developed because current investigations have identified the various components and molecular mechanism of the effects of venoms under in vitro and in vivo conditions. The aim of this review is to describe the recent findings regarding the role of venoms and their components in treatment of MS disease and that whether venom therapy could be recommended as a complementary treatment or not.
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Affiliation(s)
- Abbas Mirshafiey
- Department of Immunology, School of Public Health, Medical Sciences, University of Tehran, Box 6446, Tehran 14155, Iran.
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Salazar AM, Rodriguez-Acosta A, Girón ME, Aguilar I, Guerrero B. A comparative analysis of the clotting and fibrinolytic activities of the snake venom (Bothrops atrox) from different geographical areas in Venezuela. Thromb Res 2007; 120:95-104. [PMID: 17045631 DOI: 10.1016/j.thromres.2006.07.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 06/28/2006] [Accepted: 07/07/2006] [Indexed: 10/24/2022]
Abstract
Venom constitution within the same snake species can present considerable geographical variations. Bothrops atrox venoms were obtained from adult snakes captured at different geographical locations: Parguasa (Bolívar state); Puerto Ayacucho 1, Serranía del Cuao and Puerto Ayacucho 2 (Amazon state). The coagulant and fibrinolytic activities of these venoms were compared. Amidolytic activity of crude snake venom was measured by a micromethod designed in our laboratory. Coagulant activity on plasma and fibrinogen due to thrombin-like activity in venoms was also determined. Crude snake venom fibrinolytic activity by the fibrin plate method was assayed. Chromatographic studies were developed on Protein-Pack 300 column. Polyacrylamide gel electrophoresis was carried out under reduced conditions. After SDS-PAGE of samples, the fibrin-zymography was tested on agarose-fibrin plates. The results demonstrated several differences among B. atrox venoms from different geographical areas. Chromatograms and SDS-PAGE profiles indicated that venoms from the same species presented differences in the molecular mass of their components. The procoagulant activity depended on the utilized method (amidolytic versus clotting). Parguasa and Puerto Ayacucho 2 venoms presented procoagulant activity for both methods. Furthermore, Parguasa venom had also the highest hemorrhagic activity and the lowest LD50. In relation to the fibrinolytic activity, Puerto Ayacucho 1 venom was the most active, equally for fibrin plates as for the amidolytic method (t-PA like). This venom had the lowest coagulant activity, which induced us to think that probably its procoagulant activity was interfered by its fibrinolytic activity.
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Affiliation(s)
- Ana Maria Salazar
- Laboratorio de Fisiopatología, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, Apartado 21827, Caracas 1020A, Venezuela
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Furtado MFD, Travaglia-Cardoso SR, Rocha MMT. Sexual dimorphism in venom of Bothrops jararaca(Serpentes: Viperidae). Toxicon 2006; 48:401-10. [PMID: 16889808 DOI: 10.1016/j.toxicon.2006.06.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Revised: 06/14/2006] [Accepted: 06/19/2006] [Indexed: 11/19/2022]
Abstract
Bothrops jararaca is an abundant snake in Brazil, and its venom has been studied exhaustively. The species exhibits adult size dimorphism in which female are larger. We registered the growth in Snout-Vent Length and weight of one litter (with 11 females and 12 males). We compared growth curves and venom profile between male and female of B. jararaca in order to establish the relationship of those characters and sex. Their venoms were analyzed when they were 36 months old, concerning SDS PAGE, protein content, proteolytic, hyaluronidasic, phospholipasic, blood-clotting, edematogenic, hemorrhagic, myotoxic activities, and lethality. Differences in the growth curves of the females and the males were significantly different after the 12th month of age, with the females growing faster. Females produced five times more venom than males. The electrophoretic patterns were variable: the venom from males had more protein bands than females. Venom composition varied significantly between males and females. Venom from females is more potent for hyaluronidasic, hemorrhagic, and lethality activities, whereas venom from males is more potent for coagulant, phospholipasic, and myotoxic activities. The variability of proteolytic and edematogenic activities were not significant. The important sexual dimorphism in body size and mass, amount of venom produced, and venom composition in B. jararaca may reflect a divergence in niche partitioning.
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Affiliation(s)
- M F D Furtado
- Laboratório de Herpetologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, Sao Paulo, SP, Brazil.
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28
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Assafim M, Ferreira MS, Frattani FS, Guimarães JA, Monteiro RQ, Zingali RB. Counteracting effect of glycyrrhizin on the hemostatic abnormalities induced by Bothrops jararaca snake venom. Br J Pharmacol 2006; 148:807-13. [PMID: 16751793 PMCID: PMC1617072 DOI: 10.1038/sj.bjp.0706786] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. Envenomation by the snake Bothrops jararaca is typically associated with hemostatic abnormalities including pro- and anticoagulant disturbances. Glycyrrhizin (GL) is a plant-derived thrombin inhibitor that also exhibits in vivo antithrombotic properties. Here, we evaluated the ability of GL to counteract the hemostatic abnormalities promoted by B. jararaca venom. 2. GL inhibited the human fibrinogen clotting (IC50 = approximately 1.0 mg ml(-1); 1.2 mM), H-D-phenylalanyl-L-pipecolyl-L-arginine-p-nitroanilide dihydrochloride hydrolysis (IC50 = approximately 0.4 mg ml(-1); 0.47 mM) and platelet aggregation (IC50 = approximately 0.28 mg ml(-1); 0.33 mM) induced by B. jararaca venom, in vitro. 3. The in vivo effect of GL was tested in rats using a model of venous thrombosis in which intravenous (i.v.) administration of B. jararaca venom (100 microg kg(-1)) produced in all animals a thrombus with a mean weight of 10.6+/-1.7 mg. 4. Prior administration of GL (180 mg kg(-1)) or antibothropic serum (27 microl kg(-1)) inhibited thrombus formation by 86 and 67%, respectively. Remarkably, co-administration of ineffective doses of GL and antibothropic serum markedly decreased thrombus weight, suggesting a synergistic effect. 5. Co-administration of GL with antibothropic serum abolished venom-induced bleeding. Ex vivo clotting times showed that rat plasma was non-clotting after i.v. administration of B. jararaca venom. Treatment with GL, antibothropic serum or both before venom administration efficiently prevented this abnormality. 6. Altogether, we demonstrate here that GL prevents both in vitro and in vivo venom-induced changes in hemostasis, suggesting a potential antiophidic activity.
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Affiliation(s)
- Mariane Assafim
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcos S Ferreira
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Flávia S Frattani
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jorge A Guimarães
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Robson Q Monteiro
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Russolina B Zingali
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Author for correspondence:
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Abstract
For centuries snake venoms have been known to interfere with haemostasis and this is now known basically due either to toxins activating/inhibiting clotting factors, having effects on blood vessels or interfering with platelet function. In this short review, the interaction of one major group of toxins, the snake venom metalloproteinases, with platelets is considered. This is relevant for understanding the mechanism of haemorrhage induced by these toxins.
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Affiliation(s)
- Aura S Kamiguti
- Department of Haematology, University of Liverpool, Daulby Street, Liverpool L69 3GA, UK.
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30
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Pardal PPDO, Souza SM, Monteiro MRDCDC, Fan HW, Cardoso JLC, França FOS, Tomy SC, Sano-Martins IS, de Sousa-e-Silva MCC, Colombini M, Kodera NF, Moura-da-Silva AM, Cardoso DF, Velarde DT, Kamiguti AS, Theakston RD, Warrell DA. Clinical trial of two antivenoms for the treatment of Bothrops and Lachesis bites in the north eastern Amazon region of Brazil. Trans R Soc Trop Med Hyg 2004; 98:28-42. [PMID: 14702836 DOI: 10.1016/s0035-9203(03)00005-1] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The efficacies of specific Bothrops atrox-Lachesis and standard Bothrops-Lachesis antivenoms were compared in the north eastern Amazon region of Brazil. The main aim was to investigate whether a specific antivenom raised against the venom of B. atrox, the most important Amazon snake species from a medical point of view, was necessary for the treatment of patients in this region. Seventy-four patients with local and systemic effects of envenoming by Bothrops or Lachesis snakes were randomly allocated to receive either specific (n = 38) or standard (n = 36) antivenoms. In 46 cases (24 in the standard antivenom group, 22 in the other) the snake was identified either by enzyme immunoassay or by examination of the dead snake, as B. atrox in 45, L. muta in one. Patients were similar in all clinical and epidemiological respects before treatment. Results indicated that both antivenoms were equally effective in reversing all signs of envenoming detected both clinically and in the laboratory. Venom-induced haemostatic abnormalities were resolved within 24 h after the start of antivenom therapy in most patients. The extent of local complications, such as local skin necrosis and secondary infection, was similar in both groups. There were no deaths. The incidence of early anaphylactic reactions was 18% and 19%, respectively for specific and standard antivenoms; none was life-threatening. Measurement of serum venom concentrations by enzyme immunoassay (EIA) confirmed that both antivenoms cleared venom antigenaemia effectively. EIA also revealed that one patient had been bitten by Lachesis muta, although the clinical features in this case were not distinctive.
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31
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Santos M, Melo M, Jacome D, Ferreira K, Habermehl G. Avaliação das lesões locais de cães envenenados experimentalmente com Bothrops alternatus após diferentes tratamentos. ARQ BRAS MED VET ZOO 2003. [DOI: 10.1590/s0102-09352003000500020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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32
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Castro KNC, Carvalho ALO, Almeida AP, Oliveira DB, Borba HR, Costa SS, Zingali RB. Preliminary in vitro studies on the Marsypianthes chamaedrys (boia-caá) extracts at fibrinoclotting induced by snake venoms. Toxicon 2003; 41:929-32. [PMID: 12782094 DOI: 10.1016/s0041-0101(03)00087-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The extract of Marsypianthes chamaedrys, a plant used against snakebites, in the present study was shown to inhibit fibrinoclotting induced by several Brazilian snake venoms or thrombin. These data indicate that this extract affected thrombin-like enzymes. In this first report we determine some features of the components present in the extract regarding the antifibrinoclotting action. Our results show that active components responsible for those effects are thermo-resistant and are concentrated in the methanolic fraction.
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Affiliation(s)
- K N C Castro
- Departamento de Bioquímica Médica, ICB/CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-590, Brazil
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33
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Anai K, Sugiki M, Yoshida E, Maruyama M. Neutralization of a snake venom hemorrhagic metalloproteinase prevents coagulopathy after subcutaneous injection of Bothrops jararaca venom in rats. Toxicon 2002; 40:63-8. [PMID: 11602280 DOI: 10.1016/s0041-0101(01)00189-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Coagulopathy is one of the major complications following envenomations by crotalid and viperid snakes. The present study was undertaken to examine the effect of a hemorrhagic metalloproteinase in Bothrops jararaca venom, jararafibrase I (JF I), on the development of coagulopathy using rat snakebite model. Coagulation parameters were monitored after subcutaneous injection of B. jararaca crude venom, JF I-neutralized venom and purified JF I in rats. Crude venom induced unclottable blood and fibrinogen consumption, while JF I-neutralized venom and purified JF I did not induce coagulopathy. Plasma venom antigen level of rats given JF I-neutralized venom was lower than that of rats given crude venom. We conclude that venom hemorrhagic metalloproteinases play an important role in the development of coagulopathy through rapid spreading of venom coagulation components from the injected area into systemic circulation.
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Affiliation(s)
- Keita Anai
- Department of Physiology, Miyazaki Medical College, 5200 Kihara, Kiyotake, 889-1692, Miyazaki, Japan.
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34
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Pinho FM, Burdmann EA. Fatal cerebral hemorrhage and acute renal failure after young Bothrops jararacussu snake bite. Ren Fail 2001; 23:269-77. [PMID: 11417959 DOI: 10.1081/jdi-100103499] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
An unusual case of a patient developing severe coagulopathy disorder and a clinical picture of cerebral hemorrhage and acute renal failure after young Bothrops jararacussu snake bite is reported. The mechanisms of snake venom-induced injury are discussed and similar cases in literature are revised and compared. The use of bothropic-Crotalus antivenom in severe B. jararacussu envenomation is discussed.
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Affiliation(s)
- F M Pinho
- Nephrology Division, Medical School, Goiás Federal University, Brazil
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35
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Lôbo de Araújo A, Kamiguti A, Bon C. Coagulant and anticoagulant activities of Bothrops lanceolatus (Fer de lance) venom. Toxicon 2001; 39:371-5. [PMID: 10978756 DOI: 10.1016/s0041-0101(00)00139-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Bothrops lanceolatus venom contains caseinolytic, phospholipase, esterase and haemorrhagic activities. We have investigated the coagulant and anticoagulant actions of B. lanceolatus venom on human citrated plasma and on purified plasma components. Although B. lanceolatus venom up to 50 microg/ml was unable to clot citrated plasma, at concentrations > or = 5 microg/ml the venom dose-dependently clotted purified human fibrinogen, indicating the presence of a thrombin-like enzyme. Human plasma (final concentration > or = 12.5%) dose-dependently inhibited the venom-induced fibrinogen clotting. This finding suggested that endogenous plasma protease inhibitors can affect the venom's action on fibrinogen. To investigate this possibility, B. lanceolatus venom was incubated with different plasma protease inhibitors and the activity on fibrinogen tested. alpha(2)-Macroglobulin and alpha(1)-antitrypsin did not interfere with the coagulant activity of the venom whereas the antithrombin-III/heparin complex partially inhibited this activity. A non-toxic, acidic phospholipase A(2) purified from B. lanceolatus venom prolonged the activated partial thromboplastin time in human plasma from 39.7+/-0.5 s (control with saline) to 60.2+/-0.9 s with 50 microg of PLA(2) (p<0.001), suggesting an anticoagulant activity associated with this enzyme. This anticoagulant activity may account for some of the effects of the venom on blood coagulation.
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Affiliation(s)
- A Lôbo de Araújo
- Departmento de Farmacologia, Faculdade de Ciências Médicus, Universidade Estadual de Campinas, SP, Brazil.
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36
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Serrano SM, Reichl AP, Mentele R, Auerswald EA, Santoro ML, Sampaio CA, Camargo AC, Assakura MT. A novel phospholipase A2, BJ-PLA2, from the venom of the snake Bothrops jararaca: purification, primary structure analysis, and its characterization as a platelet-aggregation-inhibiting factor. Arch Biochem Biophys 1999; 367:26-32. [PMID: 10375395 DOI: 10.1006/abbi.1999.1230] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This paper describes the isolation and primary structure analysis of a new phospholipase A2 with platelet-aggregation-inhibiting activity from the venom of Bothrops jararaca. The protein, named BJ-PLA2, was isolated by means of ammonium sulfate precipitation and anion-exchange and reversed-phase chromatographies and behaved as a homogeneous single-chain protein on SDS-PAGE. Its amino acid sequence was determined by N-terminal sequencing and analysis of overlapped chemical and proteolytic fragments by automated Edman degradation and mass spectometry determination. BJ-PLA2 consists of 124 amino acid residues and has the structural features of snake venom class II phospholipases A2. Chemical modification with p-bromophenacylbromide caused complete loss of enzymatic activity and partially affected the platelet-aggregation-inhibiting activity of BJ-PLA2.
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Affiliation(s)
- S M Serrano
- Laboratory of Biochemistry and Biophysics and Laboratory of Pathophysiology Instituto Butantan, São Paulo, 05503-900, Brazil.
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37
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Bogarín G, Romero M, Rojas G, Lutsch C, Casadamont M, Lang J, Otero R, Gutiérrez JM. Neutralization, by a monospecific Bothrops lanceolatus antivenom, of toxic activities induced by homologous and heterologous Bothírops snake venoms. Toxicon 1999; 37:551-7. [PMID: 10080358 DOI: 10.1016/s0041-0101(98)00193-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A monospecific Bothrops lanceolatus antivenom, currently used in Martinique, was tested for its efficacy in the neutralization of several toxic and enzymatic activities of the venoms of B. lanceolatus, B. atrox and B. asper. When tested by the i.p. route in mice, B. lanceolatus venom had an LD50 of 12.8 microg/g. In addition, it induced local tissue damage (hemorrhage, edema and myotoxicity) and showed indirect hemolytic activity, but was devoid of coagulant effect on human plasma in vitro and of defibrinating activity in mice. Antivenom was fully effective in the neutralization of lethal, hemorrhagic, edema-forming, myotoxic and indirect hemolytic effects of B. lanceolatus venom in assays involving preincubation of venom and antivenom. When tested against the venoms of B. asper and B. atrox, the antivenom completely neutralized the lethal, hemorrhagic, myotoxic and indirect hemolytic effects, and was partially effective in neutralizing edema-forming activity. In contrast, the antivenom was ineffective in the neutralization of in vitro coagulant and in vivo defibrinating effects induced by these two venoms.
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Affiliation(s)
- G Bogarín
- Instituto Clodomiro Picado, Facultad de Microbiologia, Universidad de Costa Rica, San José
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38
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Kamiguti AS, Zuzel M, Theakston RD. Snake venom metalloproteinases and disintegrins: interactions with cells. Braz J Med Biol Res 1998; 31:853-62. [PMID: 9698750 DOI: 10.1590/s0100-879x1998000700001] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Metalloproteinases and disintegrins are important components of most viperid and crotalid venoms. Large metalloproteinases referred to as MDC enzymes are composed of an N-terminal Metalloproteinase domain, a Disintegrin-like domain and a Cys-rich C-terminus. In contrast, disintegrins are small non-enzymatic RGD-containing cysteine-rich polypeptides. However, the disintegrin region of MDC enzymes bears a high degree of structural homology to that of the disintegrins, although it lacks the RGD motif. Despite these differences, both components share the property of being able to recognize integrin cell surface receptors and thereby to inhibit integrin-dependent cell reactions. Recently, several membrane-bound MDC enzymes, closely related to soluble venom MDC enzymes, have been described in mammalian cells. This group of membrane-anchored mammalian enzymes is also called the ADAM family of proteins due to the structure revealing A Disintegrin And Metalloproteinase domains. ADAMs are involved in the shedding of molecules from the cell surface, a property which is also shared by some venom MDC enzymes.
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Affiliation(s)
- A S Kamiguti
- Department of Haematology, Royal Liverpool University Hospital, University of Liverpool, UK.
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39
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THEAKSTON RDG, KAMIGUTI AS. VIPER ENVENOMING: EVALUATION OF TREATMENT BY RESTORATION OF HAEMOSTASIS AND VENOM CLEARANCE. ACTA ACUST UNITED AC 1998. [DOI: 10.1590/s0104-79301998000200002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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40
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Sano-Martins IS, Santoro ML, Castro SC, Fan HW, Cardoso JL, Theakston RD. Platelet aggregation in patients bitten by the Brazilian snake Bothrops jararaca. Thromb Res 1997; 87:183-95. [PMID: 9259109 DOI: 10.1016/s0049-3848(97)00118-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Patients bitten by the lancehead snake Bothrops jararaca usually develop systemic bleeding. Our aim was to evaluate platelet function in whole blood of 17 human patients bitten by this snake in São Paulo State, Brazil. Bleeding occurred in 71% of these patients, and thrombocytopenia in 53% of them. On admission, most of the patients presented with hypoaggregation to 50 microM ADP and 1.2 mg/ml ristocetin, and only 35% of them to 5 micrograms/ml collagen. Abnormal plasma levels of fibrinogen and fibrin(ogen) degradation products (FDP/fdp) were also observed. Twenty-four hours of finishing serumtherapy, bleeding had already ceased, fibrinogen and FDP/fdp levels returned to hemostatic levels, and values for platelet aggregation returned to the reference range of controls, except for ADP that still remained decreased. These findings evidence that disturbances of platelet function are also an important factor for the development of bleeding in Bothrops envenomation, as well as other known hemostatic disturbances that occur concomitantly.
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Affiliation(s)
- I S Sano-Martins
- Laboratory of Pathophysiology, Butantan Institute, São Paulo, Brazil
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41
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Kamiguti AS, Hay CR, Theakston RD, Zuzel M. Insights into the mechanism of haemorrhage caused by snake venom metalloproteinases. Toxicon 1996; 34:627-42. [PMID: 8817809 DOI: 10.1016/0041-0101(96)00017-7] [Citation(s) in RCA: 158] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Local and systemic haemorrhage are common consequences of crotaline and viperine envenoming. Several studies carried out using purified toxins have indicated that local haemorrhage can be attributed to a distinct class of venom metalloproteinases. Analyses of their cDNAs predict multi-domain enzymes, with an N-terminal metalloproteinase domain, a disintegrin-like domain and a Cys-rich C-terminus. Haemorrhagic metalloproteinases are responsible for degrading proteins of the extracellular matrix and they also have cytotoxic effects on endothelial cells. However, to date very few investigations have been carried out on the effects of venom haemorrhagic metalloproteinases on components of the haemostatic system. We describe here the effects of a high molecular weight haemorrhagic metalloproteinase, jararhagin, from the venom of a South American pit viper Bothrops jararaca, on platelet and plasma components involved in haemostasis. Jararhagin, which is not inhibited in plasma, causes the loss of the platelet collagen receptor alpha 2 beta 1 integrin (gpIa/IIa or VLA-2) and degrades the adhesive plasma protein von Willebrand factor. Alterations of these haemostatic components are known to result in bleeding. This suggests that venom haemorrhagic metalloproteinases, in addition to causing local bleeding, may also contribute to systemic haemorrhage.
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Affiliation(s)
- A S Kamiguti
- Department of Haematology, Royal Liverpool University Hospital, University of Liverpool, U.K
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42
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Sugiki M, Maruyama M, Yoshida E, Mihara H, Kamiguti AS, Theakston DG. Enhancement of plasma fibrinolysis in vitro by jararhagin, the main haemorrhagic metalloproteinase in Bothrops jararaca venom. Toxicon 1995; 33:1605-17. [PMID: 8866618 DOI: 10.1016/0041-0101(95)00102-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Jararhagin, a haemorrhagic metalloproteinase from Bothrops jararaca venom, plays an important role in systemic as well as local haemorrhage. In this study, the effect of jararhagin on the fibrinolytic system was investigated. The fibrinolytic activity of various kinds of animal plasmas was measured by the fibrin plate method. No activity was detected in plasma alone. However, after mixing plasma with jararhagin, strong fibrinolytic activity was recorded in guinea-pig, horse, dog, rabbit and human plasmas. The mechanism of the increase of firbinolytic activity by jararhagin was studied further in guinea-pig plasma. Fibrin-zymographic studies indicated that jararhagin increased tissue-type plasminogen activator (tPA) activity by the dissociation of a complex of tPA with type 1 plasminogen activator inhibitor (PAI-1). alpha 2-Plasmin inhibitor (alpha 2-PI) activity in the plasma was measured using a synthetic chromogenic substrate method after incubation with jararhagin. The alpha 2-PI activity in the plasma decreased in both time-dependent and dose-dependent manners. These in vitro results suggest that, in some animal plasmas, jararhagin increases plasma fibrinolytic activity by causing dissociation of the tPA/PAI-1 complex and by the inactivation of alpha 2-PI. It is possible that this direct action of jararhagin on the enhancement of plasma fibrinolytic activity may contribute to the aetiology of systemic haemorrhage frequently observed in human victims of B. jararaca envenoming.
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Affiliation(s)
- M Sugiki
- Department of Physiology, Miyazaki Medical College, Japan
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43
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Jorge MT, Cardoso JL, Castro SC, Ribeiro L, França FO, de Almeida ME, Kamiguti AS, Santo-Martins IS, Santoro ML, Mancau JE. A randomized 'blinded' comparison of two doses of antivenom in the treatment of Bothrops envenoming in São Paulo, Brazil. Trans R Soc Trop Med Hyg 1995; 89:111-4. [PMID: 7747293 DOI: 10.1016/0035-9203(95)90678-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
An earlier study in São Paulo state suggested that the dose for patients with mild or moderate envenoming by Bothrops snakes (mainly Bothrops jararaca) could be effectively decreased to 4 ampoules (40 mL) of Brazilian Brothrops polyspecific antivenom. The present 'blinded' study examined the lowest dose studied in the first trial (equivalent to 4 x 10 mL ampoules) and half that dose of antivenom (equivalent to 2 x 10 mL ampoules) in 2 similar groups of 170 patients who were comparable in all respects before treatment. The majority of patients showed rapid clinical improvement after treatment with either dose regimen and rapid restoration of blood coagulability and cessation of bleeding. There was no apparent difference between the 2 groups of patients in any respect. The study confirmed that, in such patients, the dose of antivenom can be decreased from 4 ampoules to 2 ampoules without reduction of therapeutic efficacy, and it is highly likely that this reduction will result in a decrease of early anaphylactic reactions caused by the antivenom.
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Affiliation(s)
- M T Jorge
- Hospital Vital Brazil, Instituto Butantan, São Paulo
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44
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Sano-Martins IS, Fan HW, Castro SC, Tomy SC, Franca FO, Jorge MT, Kamiguti AS, Warrell DA, Theakston RD. Reliability of the simple 20 minute whole blood clotting test (WBCT20) as an indicator of low plasma fibrinogen concentration in patients envenomed by Bothrops snakes. Butantan Institute Antivenom Study Group. Toxicon 1994; 32:1045-50. [PMID: 7801340 DOI: 10.1016/0041-0101(94)90388-3] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Reliability of the simple 20 minute whole blood clotting test (WBCT20) as an indicator of low plasma fibrinogen concentration in patients envenomed by Bothrops snakes. Toxicon 32, 1045-1050, 1994.--A simple whole blood clotting test (WBCT20) was assessed for its efficacy in determination of severe defibrinogenation in patients envenomed by Bothrops snakes in Brazil. There was a close relationship between the results of the WBCT20 and plasma fibrinogen levels in 69 moderately envenomed patients. The advantage of the WBCT20 over estimation of plasma fibrinogen concentrations in patients is that it is a simpler, faster and more reliable test. It is also of use in assessing the effectiveness of antivenom therapy in relation to the restoration of blood coagulability.
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Affiliation(s)
- I S Sano-Martins
- Pathophysiology Laboratory, Instituto Butantan, São Paulo, Brazil
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45
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Kamiguti AS, Desmond HP, Theakston RD, Hay CR, Zuzel M. Ineffectiveness of the inhibition of the main haemorrhagic metalloproteinase from Bothrops jararaca venom by its only plasma inhibitor, alpha 2-macroglobulin. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1200:307-14. [PMID: 7520756 DOI: 10.1016/0304-4165(94)90172-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Observations that a haemorrhagic metalloproteinase (jararhagin) from Bothrops jararaca venom had less effect on platelets suspended in plasma than in washed platelet suspensions, suggested that plasma contains naturally occurring inhibitor(s) of this enzyme. By using radiolabelled jararhagin and crossed immunoelectrophoresis, we have demonstrated the binding of this enzyme to alpha 2-macroglobulin in plasma. SDS-PAGE analysis of this binding revealed the presence of radioactivity in four bands with relative molecular masses of 640, 570, 520 and 410 kDa; in addition a small amount of 47 kDa free enzyme was demonstrable. Reduced samples showed an additional non-complexed 90 kDa fragment of alpha 2-macroglobulin generated by jararhagin. These results are compatible with a model in which, upon multiple cleavages of alpha 2-macroglobulin, the enzyme becomes covalently bound to the inhibitor, and the two halves of the inhibitor become crosslinked. However, jararhagin activity was not completely inhibited even after long incubation (60 min) with a large (10-fold) molar excess of alpha 2-macroglobulin either in plasma or a purified alpha 2-macroglobulin preparation. Kinetic studies showed that inhibition was comparatively slow, although jararhagin readily cleaved alpha 2-macroglobulin in the bait region. Therefore, the ineffectiveness of the inhibition could have resulted from a low tendency of this proteinase to form covalent complexes with the inhibitor. We conclude that the pronounced haemorrhagic activity of jararhagin can be attributed to prolonged access of this enzyme to high molecular weight substrates, even in the presence of a large molar excess of alpha 2-macroglobulin.
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Affiliation(s)
- A S Kamiguti
- University Department of Haematology, Royal Liverpool University Hospital, UK
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46
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Maruyama M, Sugiki M, Yoshida E, Shimaya K, Mihara H. Broad substrate specificity of snake venom fibrinolytic enzymes: possible role in haemorrhage. Toxicon 1992; 30:1387-97. [PMID: 1336630 DOI: 10.1016/0041-0101(92)90514-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We found previously that two fibrinolytic enzymes (jararafibrases I and II) purified from Bothrops jararaca venom displayed a haemorrhagic activity. To elucidate the mechanisms involved and the role of the enzymatic activity in haemorrhage, the enzymatic properties of the purified enzymes were examined. The substrate specificity of the enzymes was determined using type I collagen, type IV collagen, gelatin, laminin and fibronectin as substrates. The enzymes degraded type IV collagen, gelatin, laminin and fibronectin into smaller fragments, but degraded type I collagen only partially in a non-specific manner. The specific activities of jararafibrase I for type IV collagen and gelatin were 172 +/- 5 units/mg protein and 1315 +/- 177 units/mg protein, respectively. The specific activities of jararafibrase II for type IV collagen and gelatin were 9.2 +/- 0.6 units/mg protein and 143 +/- 15 units/mg protein, respectively. It was evident that the enzymes had rather broad substrate specificities and degraded basement membrane components including type IV collagen. The number of type IV collagen units of bacterial collagenase which gave the minimal haemorrhagic dose was 191.4, while the numbers of type IV collagenase units of jararafibrases I and II which gave the minimal haemorrhagic dose were 1.5 and 0.25, respectively. It is suggested that the broad substrate specificity of the enzymes is essential for inducing haemorrhage with a single enzyme.
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Affiliation(s)
- M Maruyama
- Department of Physiology, Miyazaki Medical College, Japan
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Paine M, Desmond H, Theakston R, Crampton J. Purification, cloning, and molecular characterization of a high molecular weight hemorrhagic metalloprotease, jararhagin, from Bothrops jararaca venom. Insights into the disintegrin gene family. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)50027-2] [Citation(s) in RCA: 162] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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48
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Maruyama M, Kamiguti AS, Tomy SC, Antonio LC, Sugiki M, Mihara H. Prothrombin and factor X activating properties of Bothrops erythromelas venom. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 1992; 86:549-56. [PMID: 1288438 DOI: 10.1080/00034983.1992.11812706] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The enzymatic properties of Factor II (FII) and Factor X (FX) activators from Bothrops erythromelas venom were investigated. Both activators were inhibited by ethylenediaminetetraacetate (EDTA) and 1,10-phenanthroline, and are thought to be metalloproteinases with molecular weights of 90 kDa and 70-90 kDa, respectively. The activity of the FII activator in the crude venom was about 30 times greater than that in Oxyuranus scutellatus venom and the level of FX activator activity, which was CA2+ ion dependent, was similar to that in Daboia russelli venom. The venom also had two haemorrhagic factors (58 and 105 kDa) and two fibrinolytic enzymes (18 and 58 kDa).
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Affiliation(s)
- M Maruyama
- Department of Physiology, Miyazaki Medical College, Japan
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Maruyama M, Sugiki M, Yoshida E, Mihara H, Nakajima N. Purification and characterization of two fibrinolytic enzymes from Bothrops jararaca (jararaca) venom. Toxicon 1992; 30:853-64. [PMID: 1523677 DOI: 10.1016/0041-0101(92)90383-g] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two fibrinolytic enzymes, jararafibrase I and jararafibrase II, were purified from Bothrops jararaca venom. The purified jararafibrase I and jararafibrase II ran as single protein bands on analytical polyacrylamide gel electrophoresis and had mol. wts of 47,000 +/- 2000 and 21,400 +/- 500, respectively, by SDS-polyacrylamide gel electrophoresis. The isoelectric points of jararafibrase I and jararafibrase II were 4.6 and 6.5, respectively. The specific activities of jararafibrase I and jararafibrase II were 2.2 units/mg protein and 6.3 units/mg protein, respectively. Both enzymes exhibited no detectable plasminogen activating activity. The activity of the enzymes was completely inhibited by 1,10-phenanthroline and ethylenediaminetetraacetate, suggesting that both enzymes were metalloproteinases. Jararafibrase I and jararafibrase II had single-chain protein compositions, and the amino acid sequence up to the 49th amino acid from the NH2-terminal of jararafibrase II was: Leu-Pro-Glu-His-Gln-Arg-Tyr-Ile-Glu-Leu-Phe-Ile-Val-Val-Asp-His-Gly-Met- Phe-Met-Lys-Tyr-Asn-Gly-Asn-Ser-Asp-Lys-Ile-Arg-Arg-Arg-Ile-His-Gln- Met-Val-Asn-Ile-Met-Lys-X-Ala-Tyr-Arg-Tyr-Leu-Tyr-Ile-(X = not confirmed).
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Affiliation(s)
- M Maruyama
- Department of Physiology, Miyazaki Medical College, Japan
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Kamiguti AS, Cardoso JL, Theakston RD, Sano-Martins IS, Hutton RA, Rugman FP, Warrell DA, Hay CR. Coagulopathy and haemorrhage in human victims of Bothrops jararaca envenoming in Brazil. Toxicon 1991; 29:961-72. [PMID: 1949067 DOI: 10.1016/0041-0101(91)90079-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Thirty-four patients envenomed by Bothrops jararaca in Brazil were studied. Of these, 20 (59%) had incoagulable blood associated with local and/or systemic bleeding and 10 of the 20 were thrombocytopenic. Among 14 patients with coagulable blood, 6 (43%) had bleeding symptoms and 3 (21%) were thrombocytopenic. High levels of von Willebrand factor (vWF), plasminogen activator inhibitor type 1 (PAI-1) and tissue type plasminogen activator (t-PA) antigens were also recorded in some patients with systemic bleeding with or without incoagulable blood. These substances may have been released from endothelial cells. Admission serum venom antigen levels were similar in both groups. The study indicated that systemic haemorrhage may occur in patients with coagulable blood and thrombocytopenia and that coagulopathy is not therefore the primary cause of haemorrhage.
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Affiliation(s)
- A S Kamiguti
- Haemophilia Centre, Royal Free Hospital, London, U.K
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