242 results on '"Gutiérrez, José María"'
Search Results
2. Skeletal muscle fiber hypercontraction induced by Bothrops asper myotoxic phospholipases A2ex vivo does not involve a direct action on the contractile apparatus
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López-Dávila, Alfredo Jesús, Weber, Natalie, Nayak, Arnab, Fritz, Leon, Moustafa, Kian Rami, Gand, Luis Vincens, Wehry, Enke, Kraft, Theresia, Thum, Thomas, Fernández, Julián, Gutiérrez, José María, and Lomonte, Bruno
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- 2023
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3. Alterations of the skeletal muscle contractile apparatus in necrosis induced by myotoxic snake venom phospholipases A2: a mini-review.
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López-Dávila, Alfredo Jesús, Lomonte, Bruno, and Gutiérrez, José María
- Abstract
Skeletal muscle necrosis is a common clinical manifestation of snakebite envenoming. The predominant myotoxic components in snake venoms are catalytically-active phospholipases A
2 (PLA2 ) and PLA2 homologs devoid of enzymatic activity, which have been used as models to investigate various aspects of muscle degeneration. This review addresses the changes in the contractile apparatus of skeletal muscle induced by these toxins. Myotoxic components initially disrupt the integrity of sarcolemma, generating a calcium influx that causes various degenerative events, including hypercontraction of myofilaments. There is removal of specific sarcomeric proteins, owing to the hydrolytic action of muscle calpains and proteinases from invading inflammatory cells, causing an initial redistribution followed by widespread degradation of myofibrillar material. Experiments using skinned cardiomyocytes and skeletal muscle fibers show that these myotoxins do not directly affect the contractile apparatus, implying that hypercontraction is due to cytosolic calcium increase secondary to sarcolemmal damage. Such drastic hypercontraction may contribute to muscle damage by generating mechanical stress and further sarcolemmal damage. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Comparison of the intrageneric neutralization scope of monospecific, bispecific/monogeneric and polyspecific/monogeneric antisera raised in horses immunized with sub-Saharan African snake venoms.
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Sánchez, Andrés, Durán, Gina, Segura, Álvaro, Herrera, María, Vargas, Mariángela, Villalta, Mauren, Arguedas, Mauricio, Moscoso, Edwin, Umaña, Deibid, Gómez, Aarón, Gutiérrez, José María, and León, Guillermo
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SNAKEBITES ,SNAKE venom ,IMMUNE serums ,COBRAS ,ANTIVENINS ,ANTIBODY formation ,REPTILES - Abstract
Background: Snakebite envenomation inflicts a high burden of mortality and morbidity in sub-Saharan Africa. Antivenoms are the mainstay in the therapy of envenomation, and there is an urgent need to develop antivenoms of broad neutralizing efficacy for this region. The venoms used as immunogens to manufacture snake antivenoms are normally selected considering their medical importance and availability. Additionally, their ability to induce antibody responses with high neutralizing capability should be considered, an issue that involves the immunization scheme and the animal species being immunized. Methodology/Principal findings: Using the lethality neutralization assay in mice, we compared the intrageneric neutralization scope of antisera generated by immunization of horses with monospecific, bispecific/monogeneric, and polyspecific/monogeneric immunogens formulated with venoms of Bitis spp., Echis spp., Dendroaspis spp., spitting Naja spp. or non-spitting Naja spp. It was found that the antisera raised by all the immunogens were able to neutralize the homologous venoms and, with a single exception, the heterologous congeneric venoms (considering spitting and non-spitting Naja separately). In general, the polyspecific antisera of Bitis spp, Echis spp, and Dendroaspis spp gave the best neutralization profile against venoms of these genera. For spitting Naja venoms, there were no significant differences in the neutralizing ability between monospecific, bispecific and polyspecific antisera. A similar result was obtained in the case of non-spitting Naja venoms, except that polyspecific antiserum was more effective against the venoms of N. melanoleuca and N. nivea as compared to the monospecific antiserum. Conclusions/Significance: The use of polyspecific immunogens is the best alternative to produce monogeneric antivenoms with wide neutralizing coverage against venoms of sub-Saharan African snakes of the Bitis, Echis, Naja (non-spitting) and Dendroaspis genera. On the other hand, a monospecific immunogen composed of venom of Naja nigricollis is suitable to produce a monogeneric antivenom with wide neutralizing coverage against venoms of spitting Naja spp. These findings can be used in the design of antivenoms of wide neutralizing scope for sub-Saharan Africa. Author summary: Parenteral administration of antivenoms is the core of the current treatment of snakebite envenomations, and there is an urgent need to produce antivenoms of wide neutralizing efficacy for sub-Saharan Africa. The active substance of antivenoms are antibodies (or antibody fragments) purified from plasma of horses or sheep immunized by the repeated injection of snake venoms. Generally, these antibodies can neutralize the venoms used as immunogens and other related venoms. Normally, the venoms used as immunogens are selected considering their medical importance and availability. To complement these criteria with information regarding the immunogenicity of venoms, we compared monospecific, bispecific/monogeneric, and polyspecific/monogeneric antisera towards venoms of Bitis spp., Echis spp., Dendroaspis spp., spitting Naja spp. or non-spitting Naja spp, regarding their intrageneric neutralization scope, evaluated by the lethality neutralization assay in mice. We found that the polyspecific antisera against venoms of Bitis spp, Echis spp, Dendroaspis spp, or non-spitting Naja gave the best neutralization profile. On the other hand, the monospecific, bispecific and polyspecific antisera towards venoms of spitting Naja venoms showed a similar performance. This information suggests that polyspecific immunogens could be the best alternative to produce antivenoms with the widest neutralizing coverage against sub-Saharan African snake venoms. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Landscape of toxin-neutralizing therapeutics for snakebite envenoming (2015–2022): Setting the stage for an R&D agenda.
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Borri, Juliette, Gutiérrez, José María, Knudsen, Cecilie, Habib, Abdulrazaq G., Goldstein, Maya, and Tuttle, Andrew
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SNAKEBITES , *SNAKE venom , *NEGLECTED diseases , *THERAPEUTICS , *INVESTIGATIONAL drugs - Abstract
Background: Progress in snakebite envenoming (SBE) therapeutics has suffered from a critical lack of data on the research and development (R&D) landscape. A database characterising this information would be a powerful tool for coordinating and accelerating SBE R&D. To address this need, we aimed to identify and categorise all active investigational candidates in development for SBE and all available or marketed products. Methodology/Principal findings: In this landscape study, publicly available data and literature were reviewed to canvas the state of the SBE therapeutics market and research pipeline by identifying, characterising, and validating all investigational drug and biologic candidates with direct action on snake venom toxins, and all products available or marketed from 2015 to 2022. We identified 127 marketed products and 196 candidates in the pipeline, describing a very homogenous market of similar but geographically bespoke products and a diverse but immature pipeline, as most investigational candidates are at an early stage of development, with only eight candidates in clinical development. Conclusions/Significance: Further investment and research is needed to address the shortfalls in products already on the market and to accelerate R&D for new therapeutics. This should be accompanied by efforts to converge on shared priorities and reshape the current SBE R&D ecosystem to ensure translation of innovation and access. Author summary: Snakebite envenoming (SBE) is a neglected tropical disease that exerts a high impact worldwide, especially in sub-Saharan Africa, Asia, and Latin America. Animal-derived antivenoms constitute the only specific, scientifically validated treatment for envenomings, although new therapeutic alternatives are being pursued. Despite the relevance of this disease, there is a critical lack of data on the research and development landscape in antivenoms and novel therapeutics. This study describes a thorough search of the state of SBE therapeutic market and research pipeline. A total of 127 marketed products and 196 candidates were identified. The current antivenom landscape is characterised by a homogeneous market of similar but geographically bespoke products needing improvement. The R&D pipeline analysis component revealed a diverse but immature picture since only eight candidates are in clinical development. This article interprets the findings of the study to provide an initial list of priority areas that sets the stage for further development of an R&D agenda to ensure translation of innovation to reduce the impact of SBE. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Tissue damaging toxins in snake venoms: mechanisms of action, pathophysiology and treatment strategies.
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Bittenbinder, Mátyás A., van Thiel, Jory, Cardoso, Fernanda C., Casewell, Nicholas R., Gutiérrez, José-María, Kool, Jeroen, and Vonk, Freek J.
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SNAKE venom ,VENOM ,PUBLIC health ,CYTOTOXINS ,ACUTE kidney failure ,PATHOLOGICAL physiology ,TOXINS - Abstract
Snakebite envenoming is an important public health issue responsible for mortality and severe morbidity. Where mortality is mainly caused by venom toxins that induce cardiovascular disturbances, neurotoxicity, and acute kidney injury, morbidity is caused by toxins that directly or indirectly destroy cells and degrade the extracellular matrix. These are referred to as 'tissue-damaging toxins' and have previously been classified in various ways, most of which are based on the tissues being affected (e.g., cardiotoxins, myotoxins). This categorisation, however, is primarily phenomenological and not mechanistic. In this review, we propose an alternative way of classifying cytotoxins based on their mechanistic effects rather than using a description that is organ- or tissue-based. The mechanisms of toxin-induced tissue damage and their clinical implications are discussed. This review contributes to our understanding of fundamental biological processes associated with snakebite envenoming, which may pave the way for a knowledge-based search for novel therapeutic options. The snake venom toxins responsible for tissue damage, their mechanisms of action and pathological effects are reviewed, together with the search of novel therapeutic alternatives to abrogate their effects [ABSTRACT FROM AUTHOR]
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- 2024
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7. A Complex Pattern of Gene Expression in Tissue Affected by Viperid Snake Envenoming: The Emerging Role of Autophagy-Related Genes.
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Oliveira, Ana Karina de, Rucavado, Alexandra, Escalante, Teresa, Gutiérrez, José María, and Fox, Jay W.
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SNAKE venom ,VENOM ,GENE expression ,FER-de-lance ,TRANSFORMING growth factors ,APOPTOSIS ,METABOLIC regulation - Abstract
Viperid snake venoms induce severe tissue damage, characterized by the direct toxic action of venom components, i.e., phospholipases A
2 (PLA2 s) and metalloproteinases (SVMPs), concomitantly with the onset of endogenous inflammatory processes, in an intricate scenario of tissue alterations. Understanding the expression of relevant genes in muscle tissue will provide valuable insights into the undergoing pathological and inflammatory processes. In this study, we have used the Nanostring technology to evaluate the patterns of gene expression in mouse skeletal muscle 1 h, 6 h, and 24 h after injection of the venoms of Bothrops asper and Daboia russelii, two medically relevant species in Latin America and Asia, respectively, with somewhat different clinical manifestations. The dose of venoms injected (30 µg) induced local pathological effects and inflammation in muscle tissue. We focused our analysis on genes related to extracellular matrix (ECM) metabolism, immune system, programmed cell death, and autophagy. The results revealed a complex pattern of expression of genes. Regarding ECM metabolism and regulation, up-regulated genes included proteinase inhibitor Serpine 1, thrombospondin 1, collagens 1A1 and 4A1 (at 1 h in the case of B. asper), TIMP1, MMP-3 (at 24 h), and lysil oxidase (LOX). In contrast, collagen chains 5A3 and 5A1 were down-regulated, especially at 6 h. Transforming growth factor β (TGF-β) and several genes related to myofibroblast regulation were also up-regulated, which might be related to the development of fibrosis. Several genes related to cytokine and chemokine synthesis and regulation and NFκB signaling were also up-regulated. Our observations show a variable expression of genes associated with programmed cell death and autophagy, thus revealing a hitherto unknown role of autophagy in tissue affected by snake venoms. These results provide clues to understanding the complex pattern of gene expression in tissue affected by viperid snake venoms, which likely impacts the final pathophysiology of damaged tissue in envenomings. [ABSTRACT FROM AUTHOR]- Published
- 2024
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8. Repurposed drugs and their combinations prevent morbidity-inducing dermonecrosis caused by diverse cytotoxic snake venoms.
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Hall, Steven R., Rasmussen, Sean A., Crittenden, Edouard, Dawson, Charlotte A., Bartlett, Keirah E., Westhorpe, Adam P., Albulescu, Laura-Oana, Kool, Jeroen, Gutiérrez, José María, and Casewell, Nicholas R.
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SNAKE venom ,VENOM ,NEGLECTED diseases ,CYTOTOXINS ,ANTIVENINS ,SMALL molecules ,SNAKEBITES - Abstract
Morbidity from snakebite envenoming affects approximately 400,000 people annually. Tissue damage at the bite-site often leaves victims with catastrophic life-long injuries and is largely untreatable by current antivenoms. Repurposed small molecule drugs that inhibit specific snake venom toxins show considerable promise for tackling this neglected tropical disease. Using human skin cell assays as an initial model for snakebite-induced dermonecrosis, we show that the drugs 2,3-dimercapto-1-propanesulfonic acid (DMPS), marimastat, and varespladib, alone or in combination, inhibit the cytotoxicity of a broad range of medically important snake venoms. Thereafter, using preclinical mouse models of dermonecrosis, we demonstrate that the dual therapeutic combinations of DMPS or marimastat with varespladib significantly inhibit the dermonecrotic activity of geographically distinct and medically important snake venoms, even when the drug combinations are delivered one hour after envenoming. These findings strongly support the future translation of repurposed drug combinations as broad-spectrum therapeutics for preventing morbidity caused by snakebite. Three drugs initially developed for other conditions, 2,3-dimercapto-1-propanesulfonic acid (DMPS), marimastat and varespladib, have shown promise in preventing the lethality of snakebite envenoming. Here, Hall et al., show that a combination of these drugs can combat the local dermonecrotic effects caused by diverse cytotoxic venoms. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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9. Industrial Production and Quality Control of Snake Antivenoms
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León, Guillermo, Segura, Álvaro, Gómez, Aarón, Hernandez, Andrés, Navarro, Diego, Villalta, Mauren, Vargas, Mariángela, Herrera, María, Gutiérrez, José María, Gopalakrishnakone, P., Editor-in-chief, and Calvete, Juan J., editor
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- 2016
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10. Skeletal muscle fiber hypercontraction induced by Bothrops asper myotoxic phospholipases A2ex vivo does not involve a direct action on the contractile apparatus.
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López-Dávila, Alfredo Jesús, Weber, Natalie, Nayak, Arnab, Fritz, Leon, Moustafa, Kian Rami, Gand, Luis Vincens, Wehry, Enke, Kraft, Theresia, Thum, Thomas, Fernández, Julián, Gutiérrez, José María, and Lomonte, Bruno
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FER-de-lance ,DIRECT action ,PHOSPHOLIPASES ,STRIATED muscle ,SKELETAL muscle ,VENOM glands ,FIBERS - Abstract
Myonecrosis is a frequent clinical manifestation of envenomings by Viperidae snakes, mainly caused by the toxic actions of secreted phospholipase A
2 (sPLA2 ) enzymes and sPLA2 -like homologs on skeletal muscle fibers. A hallmark of the necrotic process induced by these myotoxins is the rapid appearance of hypercontracted muscle fibers, attributed to the massive influx of Ca2+ resulting from cell membrane damage. However, the possibility of myotoxins having, in addition, a direct effect on the contractile machinery of skeletal muscle fibers when internalized has not been investigated. This question is here addressed by using an ex vivo model of single-skinned muscle fibers, which lack membranes but retain an intact contractile apparatus. Rabbit psoas skinned fibers were exposed to two types of myotoxins of Bothrops asper venom: Mt-I, a catalytically active Asp49 sPLA2 enzyme, and Mt-II, a Lys49 sPLA2 -like protein devoid of phospholipolytic activity. Neither of these myotoxins affected the main parameters of force development in striated muscle sarcomeres of the skinned fibers. Moreover, no microscopical alterations were evidenced after their exposure to Mt-I or Mt-II. In contrast to the lack of effects on skinned muscle fibers, both myotoxins induced a strong hypercontraction in myotubes differentiated from murine C2C12 myoblasts, with drastic morphological alterations that reproduce those described in myonecrotic tissue in vivo. As neither Mt-I nor Mt-II showed direct effects upon the contractile apparatus of skinned fibers, it is concluded that the mechanism of hypercontraction triggered by both myotoxins in patients involves indirect effects, i.e., the large cytosolic Ca2+ increase after sarcolemma permeabilization. [ABSTRACT FROM AUTHOR]- Published
- 2023
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11. Oral and IV Varespladib Rescue Experiments in Juvenile Pigs with Weakness Induced by Australian and Papuan Oxyuranus scutellatus Venoms.
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Gilliam, Lyndi L., Gilliam, John, Samuel, Stephen P., Carter, Rebecca W., Ritchey, Jerry, Bulfone, Tommaso, Gutiérrez, José María, Williams, David J., Durkin, Daniela M., Stephens, Sally I., and Lewin, Matthew R.
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VENOM ,SNAKE venom ,SURVIVAL rate ,PHOSPHOLIPASE A2 ,SPECIES specificity ,SMALL molecules ,SNAKES ,ANTIVENINS ,SWINE - Abstract
Antivenom is currently the standard-of-care treatment for snakebite envenoming, but its efficacy is limited by treatment delays, availability, and in many cases, species specificity. Many of the rapidly lethal effects of envenoming are caused by venom-derived toxins, such as phospholipase A2 (sPLA2); therefore, small molecule direct toxin inhibitors targeting these toxins may have utility as initial and adjunct therapies after envenoming. Varespladib (intravenous, IV) and varespladib-methyl (oral) have been shown to potently inhibit sPLA2s from snake venoms in murine and porcine models, thus supporting their further study as potential treatments for snakebite envenoming. In this pilot study, we tested the ability of these compounds to reverse neurotoxic effects of venom from the Australian and Papuan taipan (Oxyuranus scutellatus) subspecies in juvenile pigs (Sus domesticus). The mean survival time for control animals receiving Australian taipan venom (0.03 mg/kg, n = 3) was 331 min ± 15 min; for those receiving Papuan taipan venom (0.15 mg/kg, n = 3) it was 178 ± 31 min. Thirteen pigs received Australian taipan venom and treatment with either IV or oral varespladib (or with IV to oral transition) and all 13 survived the duration of the study (≥96 h). Eight pigs received Papuan taipan venom followed by treatment: Briefly: Two animals received antivenom immediately and survived to the end of the study. Two animals received antivenom treatment delayed 45 min from envenoming and died within 4 h. Two animals received similarly delayed antivenom treatment and were rescued by varespladib. Two animals were treated with varespladib alone after a 45-min delay. Treatment with varespladib only was effective but required repeat dosing over the course of the study. Findings highlight both the importance of early treatment and, as well, a half-life for the investigational inhibitors now in Phase II clinical trials for snakebite. Varespladib rapidly reversed weakness even when administered many hours post-envenoming and, overall, our results suggest that varespladib and varespladib-methyl could be efficacious tools in the treatment of sPLA2-induced weakness from Oxyuranus envenoming. Further clinical study as initial therapy and as potential method of rescue from some types of antivenom-resistant envenomings are supported by these data. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Effect of the time to antivenom administration on recovery from snakebite envenoming-related coagulopathy in French Guiana.
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Houcke, Stéphanie, Pujo, Jean Marc, Vauquelin, Segolene, Ngoula, Guy Roger Lontsi, Matheus, Severine, NkontCho, Flaubert, Pierre-Demar, Magalie, Gutiérrez, José María, Resiere, Dabor, Hommel, Didier, and Kallell, Hatem
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SNAKEBITES ,ANTIVENINS ,POISONS ,SNAKE venom ,HEALTH facilities ,STROKE units ,BLOOD coagulation disorders - Abstract
Background: Snakebite (SB) envenoming is an acute emergency requiring an early care delivery. We aimed to search for the time to reach healthcare facilities in various regions of French Guiana (FG) and to assess the impact of time to antivenom (AV) on the correction of coagulation parameters in these patients. Methodology: This is a prospective observational study conducted in Cayenne General Hospital between January 1st, 2016, and July 31st, 2022. We included all patients hospitalized for SB envenoming less than 48h after the bite, and receiving antivenom (AV). We assessed the time lapse between SB and medical attention and the time needed to return of the coagulation parameters to normal. Principal findings: Overall, 119 patients were investigated, and 48.7% were from remote areas. The median time from SB to AV therapy was 09:15 h (05:32–17:47). The time was longer in patients from remote rural locations. AV was dispensed within the first six hours after the SB in 45 cases (37.8%). Time from SB to reaching normal plasma fibrinogen concentration was 23:27 h (20:00–27:10) in patients receiving AV≤6h vs. 31:23 h (24:00–45:05) in those receiving AV>6h (p<0.001). Whereas, the time from AV administration to reach normal fibrinogen dosage was similar in the two groups. Conclusions: Patients from rural settings in FG suffer from a delay in AV administration after SB envenoming leading to an extended time in which patients are coagulopathic. Once AV is administered, clotting parameters recover at a similar rate. Supplying remote healthcare facilities with AV and with medical teams trained in its use should be planned. Author summary: Snakebite envenoming is a public health concern in the Amazon region. It represents an acute medical emergency needing early care such as stroke, severe trauma, myocardial infarction, etc. Antivenoms are the most effective treatment of snakebite envenomings. They are part of the WHO List of essential medicines and should be available in any primary health care where snakebite victims are managed. In this context, less than 6 hours delay between the snakebite and the antivenom administration is needed for a maximal chance to prevent and reverse most of the toxic effects of the snake venom. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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13. Mapping the Immune Cell Microenvironment with Spatial Profiling in Muscle Tissue Injected with the Venom of Daboia russelii.
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de Oliveira, Ana K., Pramoonjago, Patcharin, Rucavado, Alexandra, Moskaluk, Christopher, Silva, Dilza T., Escalante, Teresa, Gutiérrez, José María, and Fox, Jay W.
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VENOM ,MUSCLE cells ,SNAKE venom ,EXTRACELLULAR matrix ,BIOMARKERS ,IMMUNOSTAINING ,VENOM glands - Abstract
Pathological and inflammatory events in muscle after the injection of snake venoms vary in different regions of the affected tissue and at different time intervals. In order to study such heterogeneity in the immune cell microenvironment, a murine model of muscle necrosis based on the injection of the venom of Daboia russelii was used. Histological and immunohistochemical methods were utilized to identify areas in muscle tissue with a different extent of muscle cell damage, based on the presence of hypercontracted muscle cells, a landmark of necrosis, and on the immunostaining for desmin. A gradient of inflammatory cells (neutrophils and macrophages) was observed from heavily necrotic areas to less damaged and non-necrotic areas. GeoMx
® Digital Spatial Profiler (NanoString, Seattle, WA, USA) was used for assessing the presence of markers of various immune cells by comparing high-desmin (nondamaged) and low-desmin (damaged) regions of muscle. Markers of monocytes, macrophages, M2 macrophages, dendritic cells, neutrophils, leukocyte adhesion and migration markers, and hematopoietic precursor cells showed higher levels in low-desmin regions, especially in samples collected 24 hr after venom injection, whereas several markers of lymphocytes did not. Moreover, apoptosis (BAD) and extracellular matrix (fibronectin) markers were also increased in low-desmin regions. Our findings reveal a hitherto-unknown picture of immune cell microheterogeneity in venom-injected muscle which greatly depends on the extent of muscle cell damage and the time lapse after venom injection. [ABSTRACT FROM AUTHOR]- Published
- 2023
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14. Role of nitric oxide and signaling pathways modulating the stimulatory effect of snake venom secretory PLA2S on non-opsonized zymosan phagocytosis by macrophages.
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Zuliani, Juliana Pavan, Gutiérrez, José María, and Teixeira, Catarina
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SNAKE venom , *VENOM , *PHAGOCYTOSIS , *ZYMOSAN , *CELLULAR signal transduction , *NITRIC oxide , *FER-de-lance - Abstract
The phagocytic activity of macrophages activated with MT-II, a Lys-49 PLA 2 homolog, and MT-III, an Asp-49 PLA 2 , from Bothrops asper snake venom, was investigated in this study using a pharmacological approach. Stimulating thioglycollate-elicited macrophages with both venom components enhanced their ability to phagocytose non-opsonized zymosan particles. MT-II and MT–III–induced phagocytosis was drastically inhibited by pretreating cells with L-NAME, aminoguanidine or L-NIL, cNOS or iNOS inhibitors, or with ODQ (sGC inhibitor) or Rp-cGMPS (PKG inhibitor). These results indicate that the NO/sGC/GMP/PKG pathway plays an essential role in the β-glucan-mediated phagocytosis induced in macrophages by these venom-secretory PLA 2 s. [Display omitted] • -The PLA2s MT-II and MT-III induced zymosan phagocytosis. • -Nitric oxide is involved in both PLA 2 s-induced phagocytosis. • -sGC, GMP, and PKG are signaling pathways that play a role in phagocytosis induced by PLA 2 s. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. In Vitro Tests for Assessing the Neutralizing Ability of Snake Antivenoms: Toward the 3Rs Principles.
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Gutiérrez, José María, Vargas, Mariángela, Segura, Álvaro, Herrera, María, Villalta, Mauren, Solano, Gabriela, Sánchez, Andrés, Herrera, Cristina, and León, Guillermo
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ANTIVENINS ,IN vitro toxicity testing ,IN vivo toxicity testing ,EGGS ,SNAKE venom - Abstract
There is an urgent need to strengthen the implementation of the 3Rs principle (Replacement, Reduction and Refinement) in the use of experimental animals in toxinological research and in the assessment of the neutralizing efficacy of snake antivenoms. This is a challenging task owing to the inherent complexity of snake venoms. The state of the art on this topic is hereby reviewed, with emphasis on the studies in which a correlation has been observed between in vivo toxicity tests and in vitro surrogate assays, particularly in the study of lethal activity of venoms and its neutralization. Correlations have been described with some venoms-antivenoms when using: (a) enzyme immunoassays, (b) hemagglutination, (c) enzyme assays (proteinase, phospholipase A
2 ), (d) in vitro coagulant effect on plasma, (e) cell culture assays for cytotoxicity, (f) functional assays for assessing neurotoxicity in vitro , (g) use of hens' eggs, and (h) antivenomics. Additionally, the routine introduction of analgesia in these assays and the design of more 'humane' protocols for the lethality test are being pursued. It is expected that the next years will witness a growing awareness of the relevance of the 3Rs principles in antivenom testing, and that new in vitro alternatives and more 'humane' experimental designs will emerge in this field. [ABSTRACT FROM AUTHOR]- Published
- 2021
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16. Enzyme immunoassays for detection and quantification of venoms of Sri Lankan snakes: Application in the clinical setting.
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Maduwage, Kalana Prasad, Gawarammana, Indika Bandara, Gutiérrez, José María, Kottege, Chaminda, Dayaratne, Rohana, Premawardena, Nuwan Prasada, and Jayasingha, Sujeewa
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SNAKEBITES ,ENZYME-linked immunosorbent assay ,VENOM ,ANTIVENINS ,SNAKE venom ,TROPICAL medicine - Abstract
Background: Detection and quantification of snake venom in envenomed patients' blood is important for identifying the species responsible for the bite, determining administration of antivenom, confirming whether sufficient antivenom has been given, detecting recurrence of envenoming, and in forensic investigation. Currently, snake venom detection is not available in clinical practice in Sri Lanka. This study describes the development of enzyme immunoassays (EIA) to differentiate and quantify venoms of Russell's viper (Daboia russelii), saw-scaled viper (Echis carinatus), common cobra (Naja naja), Indian krait (Bungarus caeruleus), and hump-nosed pit viper (Hypnale hypnale) in the blood of envenomed patients in Sri Lanka. Methodology / Principal findings: A double sandwich EIA of high analytical sensitivity was developed using biotin-streptavidin amplification for detection of venom antigens. Detection and quantification of D. russelii, N. naja, B. caeruleus, and H. hypnale venoms in samples from envenomed patients was achieved with the assay. Minimum (less than 5%) cross reactivity was observed between species, except in the case of closely related species of the same genus (i.e., Hypnale). Persistence/ recurrence of venom detection following D. russelii envenoming is also reported, as well as detection of venom in samples collected after antivenom administration. The lack of specific antivenom for Hypnale sp envenoming allowed the detection of venom antigen in circulation up to 24 hours post bite. Conclusion: The EIA developed provides a highly sensitive assay to detect and quantify five types of Sri Lankan snake venoms, and should be useful for toxinological research, clinical studies, and forensic diagnosis. Author summary: Snakebite is a major medical and public health problem in tropical agricultural world. Detection of the type of snake venom and measurement of venom levels in blood are important for snakebite research, selecting the appropriate antivenom, and assessing venom levels in blood at the clinical setting. Currently, a snake venom detection platform is not available in clinical practice in Sri Lanka. This study aimed to develop a double sandwich enzyme immunoassays (EIA) to differentiate and quantify venoms of Russell's viper (Daboia russelii), saw-scaled viper (Echis carinatus), common cobra (Naja naja), Indian krait (Bungarus caeruleus), and hump-nosed pit viper (Hypnale hypnale) in blood samples of envenomed patients in Sri Lanka. The EIA developed used biotin-streptavidin amplification for detection of venom antigens and showed high analytical sensitivity. The assay allowed the quantification of venoms of the five species in blood samples from envenomed patients. Low level of cross reactivity was noted between species, except in the case of closely related Hypnale species. The presence of D. russelii venom after antivenom treatment is reported, a finding that has implications in the dosing of antivenom in these envenomings. Lack of specific antivenom for H. hypnale envenoming offered an opportunity of study the remaining venom antigen in circulation up to 24 hr post bite. The EIA developed constitutes a useful tool to detect and quantify the five types of Sri Lankan snake venoms, and should be useful for research purposes, as well as for the diagnosis and therapy evaluation of clinical cases of envenomings in this country, and for forensic purposes. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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17. An in vitro α-neurotoxin—nAChR binding assay correlates with lethality and in vivo neutralization of a large number of elapid neurotoxic snake venoms from four continents.
- Author
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Pruksaphon, Kritsada, Tan, Kae Yi, Tan, Choo Hock, Simsiriwong, Pavinee, Gutiérrez, José María, and Ratanabanangkoon, Kavi
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NEUROTOXIC agents ,SNAKE venom ,BINDING site assay ,NICOTINIC acetylcholine receptors ,ANTIVENINS ,POISONOUS snakes - Abstract
The aim of this study was to develop an in vitro assay for use in place of in vivo assays of snake venom lethality and antivenom neutralizing potency. A novel in vitro assay has been developed based on the binding of post-synaptically acting α-neurotoxins to nicotinic acetylcholine receptor (nAChR), and the ability of antivenoms to prevent this binding. The assay gave high correlation in previous studies with the in vivo murine lethality tests (Median Lethal Dose, LD
50 ), and the neutralization of lethality assays (Median Effective Dose, ED50 ) by antisera against Naja kaouthia, Naja naja and Bungarus candidus venoms. Here we show that, for the neurotoxic venoms of 20 elapid snake species from eight genera and four continents, the in vitro median inhibitory concentrations (IC50s ) for α-neurotoxin binding to purified nAChR correlated well with the in vivo LD50s of the venoms (R2 = 0.8526, p < 0.001). Furthermore, using this assay, the in vitro ED50s of a horse pan-specific antiserum against these venoms correlated significantly with the corresponding in vivo murine ED50 s, with R2 = 0.6896 (p < 0.01). In the case of four elapid venoms devoid or having a very low concentration of α-neurotoxins, no inhibition of nAChR binding was observed. Within the philosophy of 3Rs (Replacement, Reduction and Refinement) in animal testing, the in vitro α-neurotoxin-nAChR binding assay can effectively substitute the mouse lethality test for toxicity and antivenom potency evaluation for neurotoxic venoms in which α-neurotoxins predominate. This will greatly reduce the number of mice used in toxicological research and antivenom production laboratories. The simpler, faster, cheaper and less variable in vitro assay should also expedite the development of pan-specific antivenoms against various medically important snakes in many parts of the world. Author summary: Snakebite envenomation is an important public health problem recognized by the World Health Organization (WHO) as a neglected tropical disease affecting about 2 million of poor people of the tropical world. The most effective therapy is the timely administration of efficacious antivenoms which are usually produced in horses. The serum/plasma of horse immunized with snake venoms is purified and tested for its efficacies in neutralizing the target venoms. The neutralization is assayed using mice injected with the venom together with the antivenom. This assay requires about 60 mice for each pair of venom and antivenom. The assay is expensive, laborious, giving highly variable results and is objected on ethical and religious grounds. The present study involves the development of an in vitro assay involving the binding of a snake neurotoxin to a soluble receptor protein called nicotinic acetylcholine receptor. It is shown here that this receptor binding assay gave good correlation with the assay using mice. The test tube assay is simpler, faster, cheaper and less variable when compared with the mouse assay and thus could reduce or even replace the use of life animal. Furthermore, it could expedite the development of effective antivenoms against various venomous snakes in many parts of the world. [ABSTRACT FROM AUTHOR]- Published
- 2020
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18. A pan-specific antiserum produced by a novel immunization strategy shows a high spectrum of neutralization against neurotoxic snake venoms.
- Author
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Ratanabanangkoon, Kavi, Tan, Kae Yi, Pruksaphon, Kritsada, Klinpayom, Chaiya, Gutiérrez, José María, Quraishi, Naeem H., and Tan, Choo Hock
- Subjects
SNAKE venom ,SNAKEBITES ,IMMUNE serums ,NEUROTOXIC agents ,IMMUNIZATION - Abstract
Snakebite envenomation is a neglected tropical disease of high mortality and morbidity largely due to insufficient supply of effective and affordable antivenoms. Snake antivenoms are mostly effective against the venoms used in their production. It is thus crucial that effective and affordable antivenom(s) with wide para-specificity, capable of neutralizing the venoms of a large number of snakes, be produced. Here we studied the pan-specific antiserum prepared previously by a novel immunization strategy involving the exposure of horses to a 'diverse toxin repertoire' consisting of 12 neurotoxic Asian snake toxin fractions/ venoms from six species. This antiserum was previously shown to exhibit wide para-specificity by neutralizing 11 homologous and 16 heterologous venoms from Asia and Africa. We now show that the antiserum can neutralize 9 out of 10 additional neurotoxic venoms. Altogether, 36 snake venoms belonging to 10 genera from 4 continents were neutralized by the antiserum. Toxin profiles previously generated using proteomic techniques of these 36 venoms identified α-neurotoxins, β-neurotoxins, and cytotoxins as predominant toxins presumably neutralized by the antiserum. The bases for the wide para-specificity of the antiserum are discussed. These findings indicate that it is feasible to generate antivenoms of wide para-specificity against elapid neurotoxic venoms from different regions in the world and raises the possibility of a universal neurotoxic antivenom. This should reduce the mortality resulting from neurotoxic snakebite envenomation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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19. "Bad things come in small packages": predicting venom-induced coagulopathy in Bothrops atrox bites using snake ontogenetic parameters.
- Author
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Bernal, Jorge Carlos Contreras, Bisneto, Pedro Ferreira, Pereira, João Pedro Tavares, Ibiapina, Hiochelson Najibe dos Santos, Sarraff, Lybia Kássia Santos, Monteiro-Júnior, Cláudio, da Silva Pereira, Handerson, Santos, Bruno, de Moura, Valeria Mourão, de Oliveira, Sâmella Silva, Lacerda, Marcus, Sampaio, Vanderson, Kaefer, Igor Luis, Gutiérrez, José María, Bernarde, Paulo Sérgio, Fan, Hui Wen, Sachett, Jacqueline, da Silva, Ana Maria Moura, and Monteiro, Wuelton Marcelo
- Subjects
SNAKEBITES ,FER-de-lance ,SNAKE venom ,BLOOD coagulation ,HOSPITAL admission & discharge ,BOTHROPS ,COLUBRIDAE - Abstract
Introduction: Snake venom composition shows significant inter- and intra-species variation. In the case of the viperid species Bothrops atrox, responsible for the majority of snakebites in the Amazon region, geographical and ontogenetic variables affect venom composition, with ecological and medical implications. Previous studies had shown that venom from neonate and juvenile Bothrops specimens have a higher in vitro coagulant activity. The aim of this investigation was to assess the association of clinical outcomes, such as venom-induced coagulopathy and local complications, with B. atrox ontogenetic variables. Methods: This study explored the relationship between some clinical parameters in patients suffering envenomations by B. atrox in the Amazon and several morphometric parameters of the snake specimens causing the bites. Results: There were 248 specimens confirmed as agents of envenomation, mostly female snakes (70.5%) and classified as juveniles (62.7%). Patients bitten by neonates compared to adult snakes [OR = 2.70 (95%CI 1.15-6.37); p =.021] and by snakes with white tail tip [OR = 1.98 (95%CI 1.15–3.41); p =.013] were more likely to develop coagulopathy. Time from patient admission to the unclottable blood reversion was not affected by the snake gender (p =.214) or age (p =.254). Patients bitten by neonate (p =.024) or juvenile snakes (p <.0001) presented a lower frequency of moderate to severe edema, as compared to those bitten by adult snakes. In agreement with experimental observations, patients bitten by neonates and by snakes with a white tail tip were more likely to develop coagulopathy than those bitten by adult snakes. In contrast, envenomations by adult snakes were associated with a higher incidence of severe local edema. Conclusion: Despite these variations, no difference was observed in the time needed to recover blood clotting in these patients after Bothrops antivenom administration. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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20. Immune response to neurotoxic South American snake venoms.
- Author
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Baudou, Federico G., Gutiérrez, José María, and Rodríguez, Juan Pablo
- Subjects
- *
VENOM , *SNAKE venom , *IMMUNE response , *ANTIVENINS , *CROTALUS , *NEUROTOXIC agents , *BOTHROPS - Abstract
South American rattlesnakes (Crotalus durissus spp) and coral snakes (Micrurus sp) venoms are characterized by inducing a limited inflammatory innate immune response, in contrast to Bothrops sp snake venoms which exert a prominent inflammatory activity. Some Crotalus durissus spp venoms, in addition, exert immunosuppressive activities that hamper the development of neutralizing antibodies in animals immunized for antivenom production. Micrurus sp venoms are rich in low molecular mass neurotoxins that elicit a limited immune response. These characteristics make it difficult to generate antivenoms of high neutralizing activity. Therefore, the study of the mechanisms operating behind this limited immune response to venoms is relevant from both fundamental and practical perspectives. This review summarizes key aspects of the immune response to these venoms and discusses some pending challenges to further understand these phenomena and to improve antivenom production. [Display omitted] • South American coral and rattlesnake venoms induce limited inflammation. • Crotalus durissus spp venoms exert immunosuppressive activities attributed to crotoxin. • Micrurus sp toxins such as 3-FTXs, are poorly immunogenic. • This type of venom elicits a poor immune response in immunized animals. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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21. Effects of bleeding in horses immunized with snake venoms for antivenom production
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Angulo, Yamileth, Estrada, Ricardo, and Gutiérrez, José María
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antivenom ,hematological parameters ,neutralization ,bleeding ,snake venom - Abstract
Hematological and clínical alterations were investigated in horses injected with snake venom and subjected to repetitive bleeding, followed by plasmapheresis
- Published
- 2015
22. Effects of Bothrops asper snake venom on the expression of cyclooxygenases and production of prostaglandins by peritoneal leukocytes in vivo, and by isolated neutrophils and macrophages in vitro
- Author
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Moreira, Vanessa, Gutiérrez, José María, Amaral, Rafaela Bacci, Zamunér, Stella Regina, and Teixeira, Catarina de Fátima
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Male ,Snake venom ,Cell Survival ,Neutrophils ,Macrophage ,Neutrophile ,Clinical Biochemistry ,Prostaglandin ,Pharmacology ,Biology ,Dinoprostone ,Proinflammatory cytokine ,Mice ,chemistry.chemical_compound ,In vivo ,Crotalid Venoms ,Leukocytes ,Animals ,Ascitic Fluid ,Bothrops ,Peritoneal Cavity ,Prostaglandin D2 ,Neutrophil ,Membrane Proteins ,Cell Biology ,Cyclooxygenases ,In vitro ,chemistry ,Eicosanoid ,Cyclooxygenase 2 ,Prostaglandin-Endoperoxide Synthases ,Immunology ,Biocatalysis ,Cyclooxygenase 1 ,Macrophages, Peritoneal ,Prostaglandins ,lipids (amino acids, peptides, and proteins) ,Injections, Intraperitoneal - Abstract
In this study, the ability of Bothrops asper snake venom (BaV) to increase the production of prostaglandins PGE2 and PGD2 was assessed in a mouse model in vivo and in inflammatory cells in vitro. In addition, the expressions of COX-1 and COX-2 were assessed. BaV induced an increment in the in vivo synthesis of PGE2 and PGD2, together with an enhanced expression of COX-2, but not of COX-1. However, enzymatic activities of COX-1 and COX-2 were increased. Incubation of isolated macrophages and neutrophils with a sub-cytotoxic concentration of BaV in vitro resulted in increased release of PGE2 and PGD2 by macrophages and PGE2 by neutrophils, concomitantly with an increment in the expression of COX-2, but not of COX-1 by both cell types. Our results demonstrate the ability of BaV to promote the expression of COX-2 and to induce the synthesis of proinflammatory prostaglandins. Macrophages and neutrophils may be important targets for this venom under in vivo situation. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2009
23. Improving the control of snakebite envenomation in Latin America and the Caribbean: a discussion on pending issues.
- Author
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Gutiérrez, José María and Fan, Hui Wen
- Subjects
SNAKEBITES ,SNAKE venom ,MORTALITY ,SCIENTIFIC community - Abstract
An editorial is presented which explores the pending issues to deal with snakebite envenomation in Latin America and the Caribbean with the aim of highlighting areas where urgent actions are required. Topics include the accurate estimation of snakebite incidence and mortality, the need to strengthen the regional research capacity and to foster links between the scientific community, the clinical realm and policymakers and the improvement of antivenom availability and accessibility.
- Published
- 2018
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24. Metalloproteinases in disease: identification of biomarkers of tissue damage through proteomics.
- Author
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Herrera, Cristina, Escalante, Teresa, Rucavado, Alexandra, Fox, Jay W., and Gutiérrez, José María
- Abstract
Introduction: Metalloproteinases play key roles in health and disease, by generating novel proteoforms with variable structure and function. Areas covered: This review focuses on the role of endogenous [a Disintegrin and Metalloproteinase (ADAMs), ADAMs with thrombospondin motifs (ADAMTS), and matrix metalloproteinases (MMPs)] and exogenous metalloproteinases in various disease conditions, and describes the application of mass spectrometry-based proteomics to detect qualitative and quantitative changes in protein profiles in tissues and body fluids in disease. Emphasis is placed on the proteomic analysis of exudates collected from affected tissues, including methods that enrich newly generated protein fragments derived from proteolysis in cells, stroma, or extracellular matrix. The use of proteomic analysis of exudates in the study of the local tissue damage induced by metalloproteinases derived from viperid snake venoms is discussed, particularly in relation to extracellular matrix degradation and to the overall pathology of these envenomings. Expert commentary: The information provided by these proteomics approaches is paving the way for the identification of biomarkers based on particular proteolytic signatures associated with different pathologies. Together with other methodological approaches, a comprehensive view of the mechanisms and dynamics of diseases can be achieved. Such basis of knowledge allows for the design of novel diagnostic and therapeutic approaches within the frame of ‘precision’ or ‘personalized’ medicine. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
25. Engineered nanoparticles bind elapid snake venom toxins and inhibit venom-induced dermonecrosis.
- Author
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O’Brien, Jeffrey, Lee, Shih-Hui, Gutiérrez, José María, and Shea, Kenneth J.
- Subjects
NANOPARTICLES ,NANOSTRUCTURED materials ,SNAKE venom ,LABORATORY mice ,PROTEINS - Abstract
Envenomings by snakebites constitute a serious and challenging global health issue. The mainstay in the therapy of snakebite envenomings is the parenteral administration of animal-derived antivenoms. Significantly, antivenoms are only partially effective in the control of local tissue damage. A novel approach to mitigate the progression of local tissue damage that could complement the antivenom therapy of envenomings is proposed. We describe an abiotic hydrogel nanoparticle engineered to bind to and modulate the activity of a diverse array of PLA
2 and 3FTX isoforms found in Elapidae snake venoms. These two families of protein toxins share features that are associated with their common (membrane) targets, allowing for nanoparticle sequestration by a mechanism that differs from immunological (epitope) selection. The nanoparticles are non-toxic in mice and inhibit dose-dependently the dermonecrotic activity of Naja nigricollis venom. [ABSTRACT FROM AUTHOR]- Published
- 2018
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26. Use of a Synthetic Biosensor for Neutralizing Activity-Biased Selection of Monoclonal Antibodies against Atroxlysin-I, an Hemorrhagic Metalloproteinase from Bothrops atrox Snake Venom
- Author
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Schneider, Francisco Santos, Nguyen, Dung Le, Castro, Karen Larissa, Cobo, Sandra, Machado de Avila, Ricardo Andrez, Ferreira, Nivia de Assis, Sanchez, Eladio Flores, Nguyen, Christophe, Granier, Claude, Galea, Pascale, Chávez-Olortegui, Carlos, Molina, Franck, Gutiérrez, José María, Sys2Diag-Modélisation et Ingénierie des Systèmes Complexes Biologiques pour le Diagnostic (Sys2Diag), Centre National de la Recherche Scientifique (CNRS)-Alcediag, UMR 9921, CNRS/UM1, Laboratoire Agronomie et Environnement (LAE), and Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
- Subjects
lcsh:Arctic medicine. Tropical medicine ,lcsh:RC955-962 ,medicine.drug_class ,[SDV]Life Sciences [q-bio] ,Immunology ,Peptide ,Venom ,Biosensing Techniques ,Monoclonal antibody ,Biochemistry ,Epitope ,Immunochemistry ,Fluorescence Resonance Energy Transfer ,medicine ,Animals ,Humans ,Mass Screening ,Bothrops ,Mass screening ,ComputingMilieux_MISCELLANEOUS ,chemistry.chemical_classification ,biology ,lcsh:Public aspects of medicine ,Immunity ,Public Health, Environmental and Occupational Health ,Antibodies, Monoclonal ,Metalloendopeptidases ,Biology and Life Sciences ,lcsh:RA1-1270 ,South America ,biology.organism_classification ,Antibodies, Neutralizing ,Vaccination and Immunization ,Molecular biology ,3. Good health ,Infectious Diseases ,chemistry ,Snake venom ,Humoral Immunity ,Clinical Immunology ,Antitoxins ,Immunotherapy ,Peptides ,Snake Venoms ,Research Article - Abstract
Background The snake Bothrops atrox is responsible for the majority of envenomings in the northern region of South America. Severe local effects, including hemorrhage, which are mainly caused by snake venom metalloproteinases (SVMPs), are not fully neutralized by conventional serum therapy. Little is known about the immunochemistry of the P-I SVMPs since few monoclonal antibodies (mAbs) against these molecules have been obtained. In addition, producing toxin-neutralizing mAbs remains very challenging. Methodology/Principal Findings Here, we report on the set-up of a functional screening based on a synthetic peptide used as a biosensor to select neutralizing mAbs against SVMPs and the successful production of neutralizing mAbs against Atroxlysin-I (Atr-I), a P-I SVMP from B. atrox. Hybridomas producing supernatants with inhibitory effect against the proteolytic activity of Atr-I towards the FRET peptide Abz-LVEALYQ-EDDnp were selected. Six IgG1 Mabs were obtained (named mAbatr1 to mAbatr6) and also two IgM. mAbatrs1, 2, 3 and 6 were purified. All showed a high specific reactivity, recognizing only Atr-I and B. atrox venom in ELISA and a high affinity, showing equilibrium constants in the nM range for Atr-I. These mAbatrs were not able to bind to Atr-I overlapping peptides, suggesting that they recognize conformational epitopes. Conclusions/Significance For the first time a functional screening based on a synthetic biosensor was successfully used for the selection of neutralizing mAbs against SVMPs., Author Summary In this work, we propose a new screening strategy to produce monoclonal antibodies against Atr-I, a P-I class SVMP from Bothrops atrox, which is the snake responsible for the majority of the accidents in South America. SVMPs are the main toxic factors in Bothrops venom causing systemic and local hemorrhage, which may evolve to inflammation and/or necrosis. Since the toxic effects of SVMPs are related to their proteolytic activity, we have produced a peptide which was used as a biosensor for Atr-I hydrolysis. Hydrolysis of this substrate was monitored and the clones possessing inhibitory activity against the proteolytic activity of Atr-I upon the peptide were selected. Using our new approach, we have obtained four monoclonal antibodies highly specific and with neutralizing capacity against the hemorrhagic activity of either Atr-I alone or Bothrops atrox whole venom. To the best of the authors' knowledge, this is the first time where a functional screening is used for the selection of neutralizing mAbs against SVMPs. It is also the first description of mAbs anti-Atr-I, with inhibitory potential against its toxic activities which may be useful for diagnosis and treatment in the future.
- Published
- 2014
27. Proteomic analysis of Bothrops pirajai snake venom and characterization of BpirMP, a new P-I metalloproteinase
- Author
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Bernardes, Carolina P., Menaldo, Danilo L., Camacho Umaña, Erika, Rosa, José C., Escalante Muñoz, Teresa, Rucavado Romero, Alexandra, Lomonte, Bruno, Gutiérrez, José María, and Sampaio, Suely V.
- Subjects
Proteomics ,Snake venom ,Basement membrane ,Proteome ,Molecular Sequence Data ,Biophysics ,Bothrops pirajai ,Hemorrhage ,Venom ,Viper Venoms ,Biochemistry ,Serine ,FOSFOLIPASES A (ISOLAMENTO E PURIFICAÇÃO) ,Crotalid Venoms ,Disintegrin ,Animals ,Humans ,Bothrops ,Amino Acid Sequence ,Metalloproteinase ,chemistry.chemical_classification ,biology ,Molecular mass ,Fibrinolysis ,Fibrinogen ,biology.organism_classification ,Molecular biology ,Amino acid ,Molecular Weight ,Phospholipases A2 ,chemistry ,Metalloproteases ,biology.protein ,Sequence Alignment - Abstract
Bothrops pirajai snake venom was analyzed by a proteomic strategy. Proteins were separated by RP-HPLC, followed by SDS-PAGE, in-gel tryptic digestion, identification by MALDI-TOF/TOF mass spectrometry, and assignment to known protein families by similarity. Proteins belonging to six families were found in B. pirajai venom, including abundant PLA 2 s and metalloproteinases, with the remaining proteins distributed among l -amino acid oxidase, serine proteinase, disintegrin and lectin-like families. A P-I class metalloproteinase, named BpirMP, was isolated from this venom by three chromatographic steps. The enzyme has a molecular mass of 23.1 kDa, as determined by mass spectrometry. Its proteolytic activity on azocasein was inhibited by chelating and reducing agents, with optimum activity at higher pH values and 37 °C. BpirMP presented weak hemorrhagic activity, with an MHD of 50 μg, and was able to hydrolyze basement membrane components in vivo and in vitro. The toxin cleaved both Aα and Bβ chains of fibrinogen and was also able to degrade fibrin and blood clots in vitro. The primary sequence analysis indicates that BpirMP contains a zinc ligand motif and a CVM motif that is associated with a Met-turn structure. These results demonstrate that BpirMP is a zinc-dependent hemorrhagic metalloproteinase with fibrin(ogen)olytic and thrombolytic activities. Biological significance This manuscript describes the diversity of protein components present in the venom of Bothops pirajai , a threatened snake species from northeastern Brazil, as well as the isolation and biochemical properties of a PI-SVMP. The results showed distinct mechanisms of action that should contribute in the elucidation of the differences in the hemorrhagic potential of SVMPs, allowing a better understanding of this class of enzymes and of the biology of Bothrops pirajai species.
- Published
- 2013
28. Unresolved issues in the understanding of the pathogenesis of local tissue damage induced by snake venoms.
- Author
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Gutiérrez, José María, Rucavado, Alexandra, Escalante, Teresa, Herrera, Cristina, Fernández, Julián, Lomonte, Bruno, and Fox, Jay W.
- Subjects
- *
SNAKE venom , *TISSUE wounds , *SNAKEBITE treatment , *DISEASE complications , *PATHOLOGICAL physiology - Abstract
Snakebite envenoming by viperid species, and by some elapids, is characterized by a complex pattern of tissue damage at the anatomical site of venom injection. In severe cases, tissue destruction may be so extensive as to lead to permanent sequelae, with serious pathophysiological, social and psychological consequences. Significant advances have been performed in the study of venom-induced tissue damage, including identification and characterization of the toxins involved, insights into the mechanisms of action of venoms and toxins, and study of tissue responses to venom-induced injury. Nevertheless, much remains to be known and understood on the pathogenesis of these alterations. This review focuses on some of the pending issues in the topic of snake venom-induced local tissue damage. The traditional ‘reductionist’ approach, which has predominated in the study of snake venoms and their actions, needs to be complemented by more integrative and holistic perspectives aimed at capturing the complexity of these pathological alterations. Future advances in the study of these topics will certainly pave the way for innovative therapeutic interventions, with the goal of reducing the impact of this aspect of snakebite envenoming. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
29. Preclinical assessment of the neutralizing efficacy of snake antivenoms in Latin America and the Caribbean: A review.
- Author
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Gutiérrez, José María
- Subjects
- *
SNAKE venom , *ANTIVENINS , *TOXICOLOGY , *METALLOPROTEINASES , *BOTHROPS - Abstract
The preclinical evaluation of the neutralizing efficacy of antivenoms is mandatory before a product is introduced for clinical use. The World Health Organization (WHO) guidelines for antivenoms categorize the tests used in preclinical studies as ‘essential assay’ (neutralization of lethality) and ‘additional recommended assays’ (neutralization of other relevant toxic activities). The present review presents an overview of the methodological aspects of snake antivenom preclinical efficacy tests, and summarizes the studies performed in this subject on antivenoms used in Latin America and the Caribbean. General trends emerging from this analysis show that: (a) Bothrops antivenoms have a broad spectrum of neutralizing efficacy against venoms of snakes of the genera Agkistrodon , Atropoides , Bothriechis , Bothrops , Cerrophidion , and Porthidium . (b) Crotalus antivenoms show a dichotomic pattern of efficacy depending on whether the venoms used for immunization are crotoxin-rich or metalloproteinase-rich. (c) A complete neutralization of Lachesis sp venoms is achieved only by antivenoms that include Lachesis sp venoms in the immunizing mixture. (d) Micrurus sp venoms have a high immunological heterogeneity which impacts in the cross-neutralization by available antivenoms. There is a need to further expand the knowledge base of the preclinical efficacy of antivenoms in Latin America and the Caribbean. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
30. A synthetic biology approach for consistent production of plant‐made recombinant polyclonal antibodies against snake venom toxins.
- Author
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Julve Parreño, Jose Manuel, Huet, Estefanía, Fernández‐del‐Carmen, Asun, Segura, Alvaro, Venturi, Micol, Gandía, Antoni, Pan, Wei‐song, Albaladejo, Irene, Forment, Javier, Pla, Davinia, Wigdorovitz, Andrés, Calvete, Juan J., Gutiérrez, Carlos, Gutiérrez, José María, Granell, Antonio, and Orzáez, Diego
- Subjects
SYNTHETIC biology ,RECOMBINANT antibodies ,SNAKE venom ,ANTIVENINS ,PHYTOTHERAPY - Abstract
Abstract: Antivenoms developed from the plasma of hyperimmunized animals are the only effective treatment available against snakebite envenomation but shortage of supply contributes to the high morbidity and mortality toll of this tropical disease. We describe a synthetic biology approach to affordable and cost‐effective antivenom production based on plant‐made recombinant polyclonal antibodies (termed pluribodies). The strategy takes advantage of virus superinfection exclusion to induce the formation of somatic expression mosaics in agroinfiltrated plants, which enables the expression of complex antibody repertoires in a highly reproducible manner. Pluribodies developed using toxin‐binding genetic information captured from peripheral blood lymphocytes of hyperimmunized camels recapitulated the overall binding activity of the immune response. Furthermore, an improved plant‐made antivenom (plantivenom) was formulated using an
in vitro selected pluribody againstBothrops asper snake venom toxins and has been shown to neutralize a wide range of toxin activities and provide protection against lethal venom doses in mice. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
31. Characterization of alpha-Neurotoxin and Phospholipase A2 Activities from Micrurus Venoms. Determination of the Amino Acid Sequence and Receptor-Binding Ability of the Major alpha-Neurotoxin from Micrurus Nigrocinctus Nigrocinctus
- Author
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Bougis, Pierre Edouard, Rosso Julien, Jean Pierre, Vargas Rosso, Orietta, Gutiérrez, José María, and Rochat, Hervé
- Subjects
Snake venom ,food.ingredient ,Molecular Sequence Data ,Neurotoxins ,Venom ,Biochemistry ,Phospholipases A ,food ,Micrurus nigrocinctus ,Animals ,Micrurus ,Amino Acid Sequence ,Elapidae ,Amino Acids ,Chromatography, High Pressure Liquid ,Phylogeny ,Toxins, Biological ,Coral snake ,Elapid Venoms ,Sequence Homology, Amino Acid ,biology ,biology.organism_classification ,Alpha-neurotoxin ,Phospholipases A2 ,Americas - Abstract
New World elapids are coral snakes that belong to the genus Micrurus, and for which the venom biochemistry is mostly unknown. Analysis has been difficult because the coral snakes produce small quantities of venom. Clinical observations following bites show mainly neurotoxic effects. Experimentally, cardiotoxic, haemolytic and myotoxic activities are also reported. An experimental approach, using reverse-phase high-performance liquid chromatography and specific assays for alpha-neurotoxin and phospholipase A2 activities, was conducted on milligram quantities of venoms from three Micrurus species from Costa Rica; M. nigrocinctus nigrocinctus, M. alleni yatesi and M. multifasciatus. Neurotoxicity was determined by competition binding experiments with the Torpedo marmorata acetylcholine receptor. Phospholipase A2 activity was measured by fluorimetry using a pyrene lipid substrate. In this way, we purified and characterized seven alpha-neurotoxins, five phospholipases A2 and four toxin homologs. The amino acid sequence of the major alpha-neurotoxin from M. nigrocinctus nigrocinctus venom was fully determined and compared to Old Word representatives. Distance matrix data were generated to set up phylogeny relationships among elapid short-chain alpha-neurotoxins, which proved to be in accordance with the taxonomic classification and geographical distribution of snake species. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 1996
32. Comparative study of the efficacy and safety of two polyvalent, caprylic acid fractionated [IgG and F(ab0)2] antivenoms, in Bothrops asper bites in Colombia
- Author
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Otero Patiño, Rafael, Segura Ruiz, Álvaro, Pereañez, Jaime Andrés, Herrera Vega, María, Angulo Ugalde, Yamileth, León Montero, Guillermo, Gutiérrez, José María, Barona, Jacqueline, Estrada, Sebastián, Quintana, Juan Carlos, Vargas Muñoz, Leidy Johana, Gómez, Juan Pablo, Díaz, Abel, Suárez, Ana María, Fernández, Jorge, Ramírez, Patricia, Fabra, Patricia E., Perea, Monica, Fernández, Diego, Arroyo, Yobana, Betancur, Dalila, Pupo, Lady, Córdoba, Elkin, Ramírez, Eugenio, Arrieta, Ana Berta, Rivero, Alcides, Mosquera, Diana Carolina, Conrado, Nectty Lorena, and Ortiz, Rosina
- Subjects
Antivenom ,F(ab0)2 ,Caprylic acid fractionation ,Snake venom ,Envenoming ,IgG ,Early adverse reactions ,Bothrops asper ,Colombia ,complex mixtures ,Venom - Abstract
2082-02 Embargo por política editorial The efficacy and safety of two polyvalent horse-derived antivenoms in Bothrops asper envenomings were tested in a randomized, double-blind, clinical trial performed in Colombia. Both antivenoms were manufactured from the same pool of hyperimmune plasma. Antivenom A was made of F(ab′)2 fragments, generated by pepsin digestion and caprylic acid precipitation, whereas antivenom B consisted of whole IgG molecules produced by caprylic acid precipitation followed by ion-exchange chromatography. Besides the different nature of the active substance, antivenom B had higher protein concentration, slightly higher turbidity and aggregate content. No significant differences were observed in the efficacy of antivenoms. Both halted local and systemic bleeding (P = 0.40) within 6–12 h of treatment in 100% of the cases, and restored blood coagulation (P = 0.87) within 6–24 h in 84.7% of patients, and within 48 h in all of them, in agreement with restoration of plasma fibrinogen concentration. Venom concentrations in serum dropped significantly (P < 0.001), to very low levels, 1 h after antivenom infusion. Nevertheless, eight patients (11.1%), four for each antivenom, presented recurrence of venom antigenaemia at different times, from 6 to 96 h, with clinical significance (recurrent coagulopathy) only in one group B patient (2.9%). Serum creatine kinase (CK) activity was increased, as a consequence of local myonecrosis. There was no significant difference (P = 0.51) in the incidence of early adverse reactions to antivenom administration (28.9% for patients of group A and 20.6% for patients of group B), most of the reactions being mild, mainly cutaneous. The most frequent complications were cellulitis (16.7%), abscess formation (5.6%), acute renal failure (8.3%), and compartmental syndrome (5.6%). In conclusion, IgG and F(ab′)2 antivenoms, prepared by caprylic acid fractionation, presented similar efficacy and safety profiles for the treatment of B. asper envenomings in Colombia. Instituto Colombiano para el Desarrollo de la Ciencia y la Tecnología Francisco José de Caldas//Colciencias/Colombia Universidad de Antioquia///Colombia Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo/[206AC0281]/CYTED/España Universidad de Costa Rica/[741-A9-003]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2012
33. Snakebite poisoning in Latin America and the Caribbean: An integral view from a regional perspective
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Gutiérrez, José María
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Snake venom ,antivenenos ,Envenenamientos ,training ,research ,América Latina y el Caribe ,prevención ,mordeduras de serpiente ,antivenoms ,Latin America and the Caribbean ,Envenomings ,prevention ,investigación ,snakebites ,capacitación - Abstract
Se analiza la situación de los envenenamientos por mordeduras de serpiente en América Latina y el Caribe, los cuales representan un importante problema de Salud Pública en la región. Esta patología afecta, fundamentalmente, a la población rural de nuestros países, y tiene un alto impacto en sectores desatendidos por los programas de salud. Estos envenenamientos son causados, en su gran mayoría, por especies de la familia Viperidae, especialmente del género Bothrops. Existe un conglomerado de laboratorios públicos y privados productores de antivenenos en la región, aunque en algunos casos la producción no satisface las necesidades de algunos países, por lo que los antivenenos deben ser importados de países vecinos. Las investigaciones científicas y tecnológicas efectuadas en América Latina han generado un gran bagaje de conocimiento sobre las serpientes y sus venenos, así como sobre la clínica de los envenenamientos y el perfil de eficacia y seguridad de los antivenenos, a niveles preclínico y clínico. Pese a los indudables logros obtenidos en el manejo de esta enfermedad en la región, se debe redoblar esfuerzos para garantizar: (a) un mejor conocimiento de los venenos y sus efectos; (b) una visión más realista de la incidencia de estos envenenamientos; (c) un mejoramiento cualitativo y cuantitativo en la producción de antivenenos; (d) un mejor control de calidad de los antivenenos que se importan en algunos países; (e) una más adecuada distribución de los antivenenos en la región, especialmente en zonas rurales de alta incidencia de envenenamientos; (f) una mayor capacitación del personal de salud en el tratamiento de estos envenenamientos, incluyendo el correcto uso de antivenenos; (g) un seguimiento y atención a las personas que han sufrido secuelas como producto de estos accidentes; y (h) programas comunitarios de prevención y atención de esta patología. Estas tareas deben ser enfrentadas con una filosofía de equidad, solidaridad y cooperación en la región, con la participación de múltiples protagonistas a muy diversos niveles. The public health problem of envenomings induced by snakebites in Latin America and the Caribbean is analyzed in this work. This pathology affects predominantly the rural population and has a high impact on regions where the provision of health services is insufficient. The majority of envenomings are inflicted by species of the genera Bothrops and Crotalus, classified in the family Viperidae. There are several laboratories in the region which manufacture antivenoms for the treatment of these envenomings, although the volume of production in some cases does not fulfill the national demand and, consequently, antivenoms have to be imported. A significant body of knowledge has been gained in the taxonomy of the snakes and the biochemistry, toxicology and immunology of venoms, as well as in the preclinical and clinical performance of antivenoms. Despite significant advances in the control of this neglected tropical disease in Latin America, there are pending tasks in the region, such as: (a) To improve our knowledge on snakes and their venoms; (b) to assess the actual incidence and mortality of snakebite envenomings; (c) to increase the volume of antivenom produced and, in some cases, to improve the quality of antivenoms; (d) to improve the national quality control laboratories; (e) to develop more effective strategies of distribution of antivenoms, especially to remote rural areas where snakebites are frequent; (f) to foster permanent education programs for the health staff in charge of the treatment of these envenomings; (g) to follow up and provide support to people that suffer physical or psychological sequelae as a consequence of these envenomings; and (h) to strengthen community programs aimed at improving the prevention and adequate management of snakebites. This conglomerate of tasks should be approached with a philosophy of solidarity, integration and cooperation in the region, with the involvement of multiple actors and institutions. Universidad de Costa Rica//UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2011
34. Membrane cholesterol modulates the cytolytic mechanism of myotoxin II, a Lys49 phospholipase A2 homologue from the venom of Bothrops asper
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Rangel Hasbún, José Andrés, Quesada, Orestes, Gutiérrez, José María, Angulo Ugalde, Yamileth, and Lomonte, Bruno
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Snake venom ,Cholesterol ,Phospholipase A2 ,Cytolysis ,Myotoxin ,Membrane ,C2C12 myoblasts ,lipids (amino acids, peptides, and proteins) ,Fluidity - Abstract
19-04-2081 Embargo por política editorial Lys49 phospholipase A2 (PLA2) homologues present in crotalid snake venoms lack enzymatic activity, yet they induce skeletal muscle necrosis by a membrane permeabilizing mechanism whose details are only partially understood. The present study evaluated the effect of altering the membrane cholesterol content on the cytolytic activity of myotoxin II, a Lys49 PLA2 isolated from the venom of Bothrops asper, using the myogenic cell line C2C12 as a model target. Cell membrane cholesterol depletion by methyl-β-cyclodextrin (MβCD) treatment enhanced the cytolytic action of myotoxin II, as well as of its bioactive C-terminal synthetic peptide p(115-129) . Conversely, cell membrane cholesterol enrichment by preformed cholesterol-MβCD complexes reduced the cytolytic effect of myotoxin II. The toxic actions of myotoxin I, a catalytically active PLA2 from the same venom, as well as of the cytolytic peptide melittin from bee venom, also increased in cholesterol-depleted cells. Although physical and functional changes resulting from variations in membrane cholesterol are complex, these findings suggest that membrane fluidity could be a relevant parameter to explain the observed modulation of the cytolytic mechanism of myotoxin II, possibly influencing bilayer penetration. In concordance, the cytolytic effect of myotoxin II decreased in direct proportion to lower temperature, a physical factor that affects membrane fluidity. In conclusion, physicochemical properties that depend on membrane cholesterol content significantly influence the cytolytic mechanism of myotoxin II, reinforcing the concept that the primary site of action of Lys49 PLA2 myotoxins is the plasma membrane. Universidad de Costa Rica/[741‐A9‐513]/UCR/Costa Rica international Centre for Genetic Engeneering and Biotechnology - Collaborative Research Programme/[COS‐ 08‐03)]/ICGEB‐CRP/Italia UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2011
35. Antivenomics of Atropoides mexicanus and Atropoides picadoi snake venoms: Relationship to the neutralization of toxic and enzymatic activities
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Antúnez, José, Fernández, Julián, Lomonte, Bruno, Angulo, Yamileth, Sanz, Libia, Pérez, Alicia, Calvete, Juan J., and Gutiérrez, José María
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Antivenom ,Snake venom ,antivenom ,Atropoides mexicanus ,Neutralization ,Immunodepletion ,Toxicity ,Antivenomics ,Atropoides picadoi ,complex mixtures ,Research Article ,Antivenoms - Abstract
11 pages, 3 figures, 3 tables. PMID:21544177[PubMed] PMCID: PMC3086187, Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an 'antivenomics' approach, the ability of a polyspecific (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are not included in the immunization mixture. In addition, the neutralization of lethal, hemorrhagic, myotoxic, coagulant, proteinase and phospholipase A(2) (PLA(2)) activities of these venoms by the antivenom was assessed. The antivenom was highly-effective in immunodepleting many venom components, particularly high molecular mass P-III metalloproteinases (SVMPs), L-amino acid oxidases, and some serine proteinases and P-I SVMPs. In contrast, PLA(2)s, certain serine proteinases and P-I SVMPs, and a C type lectin-like protein were only partially immunodepleted, and two PLA(2) molecules were not depleted at all. The antivenom was able to neutralize all toxic and enzymatic activities tested, although neutralization of lethality by A. nummifer venom was achieved when a challenge dose of 3 LD(50)s of venom was used, but was iffective when 4 LD(50)s were used. These results, and previously obtained evidence on the immunoreactivity of this antivenom towards homologous and heterologous venoms, revealed the low immunogenicity of a number of venom components (PLA(2)s, CRISPs, P-I SVMPs, and some serine proteinases), underscoring the need to search for innovative immunization protocols to improve the immune response to these antigens., This study was supported by projects from the Vicerrectoría de Investigación, Universidad de Costa Rica (741-A7- 611), CRUSA-CSIC (2007CR0004), CONARE, and grants BFU2007-61563 and BFU2010-17373 from the Ministerio de Ciencia e Innovación, Madrid, Spain
- Published
- 2010
36. Preclinical Evaluation of the Efficacy of Antivenoms for Snakebite Envenoming: State-of-the-Art and Challenges Ahead.
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Gutiérrez, José María, Solano, Gabriela, Pla, Davinia, Herrera, María, Segura, Álvaro, Vargas, Mariángela, Villalta, Mauren, Sánchez, Andrés, Sanz, Libia, Lomonte, Bruno, León, Guillermo, and Calvete, Juan J.
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ANTIVENINS , *SNAKEBITE treatment , *SNAKE venom , *PATHOLOGICAL physiology , *NEUTRALIZATION (Chemistry) - Abstract
Animal-derived antivenoms constitute the mainstay in the therapy of snakebite envenoming. The efficacy of antivenoms to neutralize toxicity of medically-relevant snake venoms has to be demonstrated through meticulous preclinical testing before their introduction into the clinical setting. The gold standard in the preclinical assessment and quality control of antivenoms is the neutralization of venom-induced lethality. In addition, depending on the pathophysiological profile of snake venoms, the neutralization of other toxic activities has to be evaluated, such as hemorrhagic, myotoxic, edema-forming, dermonecrotic, in vitro coagulant, and defibrinogenating effects. There is a need to develop laboratory assays to evaluate neutralization of other relevant venom activities. The concept of the 3Rs (Replacement, Reduction, and Refinement) in Toxinology is of utmost importance, and some advances have been performed in their implementation. A significant leap forward in the study of the immunological reactivity of antivenoms against venoms has been the development of "antivenomics", which brings the analytical power of mass spectrometry to the evaluation of antivenoms. International partnerships are required to assess the preclinical efficacy of antivenoms against snake venoms in different regions of the world in order to have a detailed knowledge on the neutralizing profile of these immunotherapeutics. [ABSTRACT FROM AUTHOR]
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- 2017
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37. Understanding the Snake Venom Metalloproteinases: An Interview with Jay Fox and José María Gutiérrez.
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Fox, Jay W. and Gutiérrez, José María
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SNAKE venom , *METALLOPROTEINASES , *TOXINS , *MOLECULAR structure , *PATHOLOGICAL physiology - Abstract
Jay W. Fox and José María Gutiérrez recently finished editing a Special Issue on the topic "Snake Venom Metalloproteinases" in Toxins. The Special Issue covers a wide range of topics, including the molecular evolution and structure of snake venom metalloproteinases (SVMPs), the mechanisms involved in the generation of diversity of SVMPs, the mechanism of action of SVMPs, and their role in the pathophysiology of envenomings, with implications for improving the therapy of envenomings. In this interview, we discussed with JayW. Fox and José María Gutiérrez their research on the SVMPs and their perspectives on the future trends and challenges for studying snake venoms. [ABSTRACT FROM AUTHOR]
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- 2017
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38. Effects of neutrophil depletion in the local pathological alterations and muscle regeneration in mice injected with Bothrops jararaca snake venom
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Teixeira, Catarina de Fátima, Chaves Mora, Fernando, Zamunér, Stella Regina, Fernandes, Cristina Maria, Zuliani, Juliana Pavan, Cruz Höfling, Maria Alice, Fernandes, Irene, and Gutiérrez, José María
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Snake venom ,Neutrophils ,Hemorrhage ,Myonecrosis ,Muscle Regeneration - Abstract
In order to study the role of neutrophils in the acute local pathological alterations induced by Bothrops jararaca snake venom, and in the process of skeletal muscle regeneration that follows, an experimental model was developed in mice pretreated with either an anti-mouse granulocyte rat monoclonal immunoglobulin G, which induces a profound neutropenia, or an isotype-matched control antibody. B. jararaca venom induced prominent haemorrhage and oedema, but only a moderate myonecrosis. No significant differences were observed in the extent of local haemorrhage, oedema and myonecrosis between neutropenic and control mice, suggesting that neutrophils do not play a determinant role in the acute pathological alterations induced by B. jararaca venom in this experimental model. Moreover, no differences were observed in skeletal muscle regeneration between these two experimental groups. In both the cases, limited areas of myonecrosis were associated with a drastic damage to the microvasculature and a scarce inflammatory infiltrate, with the consequent lack of removal of necrotic debris during the first week, resulting in a poor regenerative response at this time interval. Subsequently, a similar regenerative process occurred in both groups, and by 30 days, necrotic areas were substituted by groups of small regenerating muscle fibres. It is suggested that the drastic effect exerted by B. jararaca venom in the microvasculature precludes an effective access of inflammatory cells to necrotic areas, thereby compromising an effective removal of necrotic debris; this explains the poor regenerative response observed during the first week and the fact that there were no differences between neutropenic and control mice. As neutropenia in this model lasted only 7 days, the successful regenerative process observed at 30 days is associated with revascularization of necrotic regions and with a successful removal by phagocytes of necrotic debris in both groups. Fundação de Amparo à Pesquisa do Estado de São Paulo/[00/08890-5]/FAPESP/Brasil Fundação de Amparo à Pesquisa do Estado de São Paulo/[98/0162-9]/FAPESP/Brasil Fundação de Amparo à Pesquisa do Estado de São Paulo/[97/13089-5]/FAPESP/Brasil Universidad de Costa Rica/[741-A3-025]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2005
39. Role of TNF-α, IL-1β and IL-6 in the local tissue damage induced by Bothrops asper snake venom: an experimental assessment in mice
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Chaves Mora, Fernando, Teixeira, Catarina de Fátima, and Gutiérrez, José María
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IL-6 ,Snake venom ,Bothrops Asper Venom ,IL-1β ,TNF-α ,Hemorrhage ,Pentoxifylline ,complex mixtures ,Myonecrosis - Abstract
The role of the cytokines TNF-α, IL-1β and IL-6 in the acute local pathological effects induced by Bothrops asper snake venom was assessed in mice. Intramuscular injection of this venom induced increments in IL-1β and IL-6 in muscle, but no elevations of TNF-α were detected. Pentoxifylline (PTX), a methylxanthine derivative that inhibits the synthesis of TNF-α, and antibodies against these three cytokines were used to assess the role of these cytokines in venom-induced effects. As a control, PTX pretreatment was effective at abrogating lethality and serum TNF-α increments in mice subjected to endotoxemia induced by injection of Escherichia coli lipopolysaccharide, although it did not affect the increment in IL-1β and IL-6 in such endotoxic model. PTX failed to reduce lethality, hemorrhage, myonecrosis, dermonecrosis and edema induced by B. asper venom. Moreover, pretreatment with anti-cytokine antibodies was also ineffective at reducing venom-induced myonecrosis and hemorrhage. It is concluded that TNF-α, IL-1β and IL-6 do not have a significant role in the pathogenesis of the acute local pathological effects induced by B. asper venom in mice, although this does not exclude the possibility that these cytokines play a role in other aspects of venom-induced local pathology, as well as in the reparative and regenerative responses that take place after the onset of tissue damage. Universidad de Costa Rica/[741-A3-025]/UCR/Costa Rica United Nations Educational, Scientific and Cultural Organization/[883.701-3]/UNESCO/ UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2005
40. Characterization of events associated with apoptosis/anoikis induced by snake venom metalloproteinase BaP1 on human endothelial cells
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Díaz Oreiro, Cecilia, Valverde, Lorena, Brenes García, Oscar Gerardo, Rucavado Romero, Alexandra, and Gutiérrez, José María
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Snake venom ,Endothelial Cells ,Apoptosis ,Anoikis ,Metalloproteinase - Abstract
Human endothelial EA.hy926 cells were incubated with BaP1, a hemorrhagic metalloproteinase purified from Bothrops asper snake venom. Since the first hour of incubation with the proteinase, cells started showing DNA fragmentation, detected by a terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling (TUNEL)-based photometric enzyme-linked immunosorbent assay (ELISA). At later times, DNA fragments were predominantly located outside the cells, evidencing plasma membrane rupture. DNA fragmentation was completely abolished by Batimastat, a potent inhibitor of metalloproteinase enzymatic activity. Apoptosis induced by BaP1 on endothelial cells was independent of two Bcl-2 family members (anti-apototic Bcl-xL and pro-apoptotic Bax), that did not show any changes in their expression during a 24 h-treatment period. Interestingly, IkappaBalpha, an inhibitor of NFkappaB, decreased after 24 h of treatment, suggesting further activation of the transcription factor. When some elements of the apoptotic extrinsic pathway were assessed, it was observed that procaspase-8 completely disappeared after 24 h of treatment with BaP1, probably indicating its activation by a death receptor, whereas caspase-8 inhibitor, cellular FLICE-inhibitory protein (cFLIP(L)), increased its expression since the first hours of BaP1 incubation. In conclusion, treatment of human endothelial cells with BaP1 induces apoptosis/anoikis, independently of Bcl-2 family members Bax and Bcl-xL and associated with caspase-8 activation and cFLIP(L) up-regulation. Apoptosis was completely dependent on BaP1 enzymatic activity. Similarities between this and other endothelial cell anoikis-related systems suggest that BaP1 and other snake venom metalloproteinases may be useful experimental tools in the study of death-related events that occur when adherent cells loose contact with extracellular matrix. Wellcome Trus/[062043]//Estados Unidos Universidad de Costa Rica/[741-A0-049]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2005
41. Effects of PI and PIII Snake Venom Haemorrhagic Metalloproteinases on the Microvasculature: A Confocal Microscopy Study on the Mouse Cremaster Muscle.
- Author
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Herrera, Cristina, Voisin, Mathieu-Benoit, Escalante, Teresa, Rucavado, Alexandra, Nourshargh, Sussan, and Gutiérrez, José María
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SNAKE venom ,METALLOPROTEINASES ,HEMORRHAGE ,CONFOCAL microscopy ,IMMUNOSTAINING ,LABORATORY mice ,IN vivo studies - Abstract
The precise mechanisms by which Snake Venom Metalloproteinases (SVMPs) disrupt the microvasculature and cause haemorrhage have not been completely elucidated, and novel in vivo models are needed. In the present study, we compared the effects induced by BaP1, a PI SVMP isolated from Bothrops asper venom, and CsH1, a PIII SVMP from Crotalus simus venom, on cremaster muscle microvasculature by topical application of the toxins on isolated tissue (i.e., ex vivo model), and by intra-scrotal administration of the toxins (i.e., in vivo model). The whole tissue was fixed and immunostained to visualize the three components of blood vessels by confocal microscopy. In the ex vivo model, BaP1 was able to degrade type IV collagen and laminin from the BM of microvessels. Moreover, both SVMPs degraded type IV collagen from the BM in capillaries to a higher extent than in PCV and arterioles. CsH1 had a stronger effect on type IV collagen than BaP1. In the in vivo model, the effect of BaP1 on type IV collagen was widespread to the BM of arterioles and PCV. On the other hand, BaP1 was able to disrupt the endothelial barrier in PCV and to increase vascular permeability. Moreover, this toxin increased the size of gaps between pericytes in PCV and created new gaps between smooth muscle cells in arterioles in ex vivo conditions. These effects were not observed in the case of CsH1. In conclusion, our findings demonstrate that both SVMPs degrade type IV collagen from the BM in capillaries in vivo. Moreover, while the action of CsH1 is more directed to the BM of microvessels, the effects of BaP1 are widespread to other microvascular components. This study provides new insights in the mechanism of haemorrhage and other pathological effects induced by these toxins. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
42. Functional analysis of DM64, an antimyotoxic protein with immunoglobulin-like structure from Didelphis marsupialis serum
- Author
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Rocha, Surza Lucia Gonçalves, Lomonte, Bruno, Neves Ferreira, Ana Gisele da Costa, Trugilho, Monique Ramos de Oliveira, Junqueira de Azevedo, Inácio de Loiola Meirelles, Ho, Paulo Lee, Domont, Gilberto B., Gutiérrez, José María, and Perales, Jonas
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Didelphis marsupialis ,Snake venom ,Inhibitor ,Myotoxin ,Phospholipase - Abstract
Bothrops snake venoms are known to induce local tissue damage such as hemorrhage and myonecrosis. The opossum Didelphis marsupialis is resistant to these snake venoms and has natural venom inhibitors in its plasma. The aim of this work was to clone and study the chemical, physicochemical and biological properties of DM64, an antimyotoxic protein from opossum serum. DM64 is an acidic protein showing 15% glycosylation and with a molecular mass of 63 659 Da when analysed by MALDI-TOF MS. It was cloned and the amino acid sequence was found to be homologous to DM43, a metalloproteinase inhibitor from D. marsupialis serum, and to human α1B-glycoprotein, indicating the presence of five immunoglobulin-like domains. DM64 neutralized both the in vivo myotoxicity and the in vitro cytotoxicity of myotoxins I (mt-I/Asp49) and II (mt-II/Lys49) from Bothrops asper venom. The inhibitor formed noncovalent complexes with both toxins, but did not inhibit the PLA2 activity of mt-I. Accordingly, DM64 did not neutralize the anticoagulant effect of mt-I nor its intracerebroventricular lethality, effects that depend on its enzymatic activity, and which demonstrate the dissociation between the catalytic and toxic activities of this Asp49 myotoxic PLA2. Furthermore, despite its similarity with metalloproteinase inhibitors, DM64 presented no antihemorrhagic activity against Bothrops jararaca or Bothrops asper crude venoms, and did not inhibit the fibrinogenolytic activity of jararhagin or bothrolysin. This is the first report of a myotoxin inhibitor with an immunoglobulin-like structure isolated and characterized from animal blood. Conselho Nacional de Desenvolvimento Científico e Tecnológico//CNPq/Brasil Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro//FAPERJ/Brasil Fundação de Amparo à Pesquisa do Estado de São Paulo//FAPESP/Brasil Fundação Oswaldo Cruz//Fiocruz/Brasil UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2002
43. Characterization of aspercetin, a platelet aggregating component from the venom of the snake Bothrops asper which induces thrombocytopenia and potentiates metalloproteinase-induced hemorrhage
- Author
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Rucavado Romero, Alexandra, Soto Morera, Mónica, Kamiguti, Aura S., Theakston, R. David G., Fox, Jay W., Escalante Muñoz, Teresa, and Gutiérrez, José María
- Subjects
C-type lectin ,Snake venom ,Aspercetin ,Platelet aggregation ,Hemorrhage ,Bothrops asper venom ,Thrombocytopenia - Abstract
Thrombocytopenia occurs in a number of patients bitten by Bothrops asper, a species responsible for the majority of snakebites in Central America and southern Mexico. In this work we describe the isolation of a new platelet-aggregating protein, named aspercetin, from the venom of B. asper, which induces thrombocytopenia in mice. Isolation was carried out by a combination of ion-exchange chromatography on DEAE-Sepharose and affinity chromatography on Affi-Gel Blue. Aspercetin is a disulfide-linked heterodimer, with a pI of 4.5 and a molecular mass of 29,759 Da, detemined by MALDI-ESI mass spectrometry. N-terminal sequence shows homology with a number of venom proteins which belong to the C-type lectin family. Aspercetin has functional similarities with botrocetin, from B. jararaca venom, since it induces platelet aggregation only in the presence of plasma or purified von Willebrand factor. Aspercetin-mediated platelet aggregation results from the interaction of von Willebrand factor with platelet receptor GPIb. Aspercetin lacks anticoagulant effect and does not agglutinate erythrocytes, in contrast with other representatives of the C-type lectin family isolated from snake venoms. Moreover, aspercetin is not lethal, nor does it induce myonecrosis, hemorrhage and edema. When injected intravenously or intramuscularly in mice it induces a rapid, dose-dependent drop in platelet counts and prolongs the bleeding time, suggesting that it may play a role in the thrombocytopenia that develops in a number of B. asper envenomations. Moreover, mice injected intravenously with aspercetin and then receiving an intradermal injection of B. asper hemorrhagic metalloproteinase BaP1 develop a larger hemorrhagic lesion than mice receiving only BaP1. This suggests that aspercetin, by reducing platelet numbers, may contribute to the hemorrhagic effect characteristic of B. asper envenomations. International Foundation for Science/[F2707-2]/IFS/Suecia Universidad de Costa Rica /[741-98-505]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 2001
44. Characterization of a novel snake venom component: Kazal-type inhibitor-like protein from the arboreal pitviper Bothriechis schlegelii.
- Author
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Fernández, Julián, Gutiérrez, José María, Calvete, Juan J., Sanz, Libia, and Lomonte, Bruno
- Subjects
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SNAKE venom , *BOTHRIECHIS schlegelii , *PEPTIDE analysis , *PROTEOMICS , *AMINO acid residues , *SERINE proteinases - Abstract
Snake venoms are composed mainly of a mixture of proteins and peptides. Notably, all snake venom toxins have been assigned to a small number of protein families. Proteomic studies on snake venoms have recently identified the presence of Kazal-type inhibitor-like proteins in the neotropical arboreal snakes Bothriechis schlegelii and Bothriechis supraciliaris . In the present study, a Kazal-type component from B. schlegelii , named Kazal-type inhibitor-like protein (KTIL), has been completely sequenced and characterized for the first time. This protein, which contains 54 amino acid residues, shows sequence similarity to the third domain of the ovomucoid from avian species, which is a Kazal-like domain. KTIL did not inhibit the enzymatic activity of various serine proteinases at pH = 7.2 or pH = 8.0, but partially inhibited the activity of trypsin at pH = 5.4, and the only toxic effect in mice observed after different in vivo tests was the induction of footpad edema. KTIL was not lethal when injected in mice or chickens. The presence of Kazal-type proteins and mRNA only in species of the genus Bothriechis suggests a genus recruitment event in the early-Middle Miocene, the estimated time of emergence of this clade. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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45. Venom of the Coral Snake Micrurus clarki: Proteomic Profile, Toxicity, Immunological Cross-Neutralization, and Characterization of a Three-Finger Toxin.
- Author
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Lomonte, Bruno, Sasa, Mahmood, Rey-Suárez, Paola, Bryan, Wendy, and Gutiérrez, José María
- Subjects
CORAL snakes ,SNAKE venom ,MICRURUS (Reptiles) ,PHOSPHOLIPASE A2 ,AMINO acid sequence ,VENOM glands - Abstract
Micrurus clarki is an uncommon coral snake distributed from the Southeastern Pacific of Costa Rica to Western Colombia, for which no information on its venom could be found in the literature. Using a 'venomics' approach, proteins of at least nine families were identified, with a moderate predominance of three-finger toxins (3FTx; 48.2%) over phospholipase A
2 (PLA2 ; 36.5%). Comparison of this venom profile with those of other Micrurus species suggests that it may represent a more balanced, 'intermediate' type within the dichotomy between 3FTx- and PLA2 -predominant venoms. M. clarki venom was strongly cross-recognized and, accordingly, efficiently neutralized by an equine therapeutic antivenom against M. nigrocinctus, revealing their high antigenic similarity. Lethal activity for mice could be reproduced by a PLA2 venom fraction, but, unexpectedly, not by fractions corresponding to 3FTxs. The most abundant venom component, hereby named clarkitoxin-I, was identified as a short-chain (type I) 3FTx, devoid of lethal effect in mice, whose target remains to be defined. Its amino acid sequence of 66 residues shows high similarity with predicted sequences of venom gland transcripts described for M. fulvius, M. browni, and M. diastema. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
46. Hemorrhage Caused by Snake Venom Metalloproteinases: A Journey of Discovery and Understanding.
- Author
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Gutiérrez, José María, Escalante, Teresa, Rucavado, Alexandra, and Herrera, Cristina
- Subjects
- *
SNAKE venom , *HEMORRHAGE risk factors , *METALLOPROTEINASES , *BASAL lamina , *VIPERIDAE , *SNAKEBITES - Abstract
The historical development of discoveries and conceptual frames for understanding the hemorrhagic activity induced by viperid snake venoms and by hemorrhagic metalloproteinases (SVMPs) present in these venoms is reviewed. Histological and ultrastructural tools allowed the identification of the capillary network as the main site of action of SVMPs. After years of debate, biochemical developments demonstrated that all hemorrhagic toxins in viperid venoms are zinc-dependent metalloproteinases. Hemorrhagic SVMPs act by initially hydrolyzing key substrates at the basement membrane (BM) of capillaries. This degradation results in the weakening of the mechanical stability of the capillary wall, which becomes distended owing of the action of the hemodynamic biophysical forces operating in the circulation. As a consequence, the capillary wall is disrupted and extravasation occurs. SVMPs do not induce rapid toxicity to endothelial cells, and the pathological effects described in these cells in vivo result from the mechanical action of these hemodynamic forces. Experimental evidence suggests that degradation of type IV collagen, and perhaps also perlecan, is the key event in the onset of microvessel damage. It is necessary to study this phenomenon from a holistic, systemic perspective in which the action of other venom components is also taken into consideration. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
47. Danger in the reef: Proteome, toxicity, and neutralization of the venom of the olive sea snake, Aipysurus laevis.
- Author
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Laustsen, Andreas H., Gutiérrez, José María, Rasmussen, Arne R., Engmark, Mikael, Gravlund, Peter, Sanders, Kate L., Lohse, Brian, and Lomonte, Bruno
- Subjects
- *
PROTEOMICS , *SEA snakes , *SNAKE venom , *TOXICITY testing , *HIGH performance liquid chromatography - Abstract
Four specimens of the olive sea snake, Aipysurus laevis , were collected off the coast of Western Australia, and the venom proteome was characterized and quantitatively estimated by RP-HPLC, SDS-PAGE, and MALDI-TOF-TOF analyses. A. laevis venom is remarkably simple and consists of phospholipases A 2 (71.2%), three-finger toxins (3FTx; 25.3%), cysteine-rich secretory proteins (CRISP; 2.5%), and traces of a complement control module protein (CCM; 0.2%). Using a Toxicity Score, the most lethal components were determined to be short neurotoxins. Whole venom had an intravenous LD 50 of 0.07 mg/kg in mice and showed a high phospholipase A 2 activity, but no proteinase activity in vitro . Preclinical assessment of neutralization and ELISA immunoprofiling showed that BioCSL Sea Snake Antivenom was effective in cross-neutralizing A. laevis venom with an ED 50 of 821 μg venom per mL antivenom, with a binding preference towards short neurotoxins, due to the high degree of conservation between short neurotoxins from A. laevis and Enhydrina schistosa venom. Our results point towards the possibility of developing recombinant antibodies or synthetic inhibitors against A. laevis venom due to its simplicity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
48. Evaluation of the neutralizing ability of antivenoms for the treatment of snake bite envenoming in Central America
- Author
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Gutiérrez, José María, Rojas Céspedes, Gustavo, Bogarín, Guisella, and Lomonte, Bruno
- Subjects
Snake venom ,571.95 Toxicología ,Central America ,Toxicology - Abstract
De nombreuses envenimations ophidiennes en Amérique centrale sont dues aux crotales (famille des Viperidae) parmi lesquels Bothrops asper est le principal responsable. Quelques accidents sont provoqués par les serpents corail (famille des Elapidés, genre Micrurus). Des sérums antivenimeux (SAV) polyvalents et anti-serpent corail sont produits depuis 1967 á I´Institut Clodomiro Picado, Costa Rica. Les envenimations par crotales sont sévères et complexes, et caractérisée par des lésions locales et des désordres systémiques. L´envenimation par Micrurus sp. est caractérisée par un syndrome neurotoxique paralytique. Une série de tests de laboratoire a été adaptée á I´Institut Clodomiro Picado pour évaluer le pouvoir neutralisant des sérums antivenimeux de L´Amérique Centrale. Ces tests portent sur le pouvoir neutralisant des effets létaux, hémorragiques, oedémateux, myotoxiques, coagulants, défibrinants, neurotoxiques, protéolytiques, et des activités phospholipase A2 et hyaluronidase des venins. Ils permettent donc une évaluation précise des sérums antivenimeux fabriqués distribués en Amérique Centrale. Les résultats indiquent que les sérums antivenimeux fabriqués au Costa Rica sont efficaces contre les venins des espèces d´Amérique Centrale testées, tandis que d´autres produits disponibles dans la région ont un pouvoir neutralisant moins efficace. Ces observations montrent la nécessité d´un contróle de qualité rigoureux des sérums antivenimeux. Most snake-bite envenomings in Central America are inflicted by pit vipers (family Viperidae, subfamily Crotalinae); Bothrops asper is responsible for most accidents. A few envenomings are caused by coral snakes (family Elapidae, genus Micrurus). Polyvalent and Micrurus antivenoms have been produced in Costa Rica since 1967. Envenomings induced by pit vipers are severe and complex and are characterized by local and systemic pathophysiological alterations. Neurotoxic paralysis is the most severe effect in Micrurus envenomigs. A series of laboratory assays has been adapted at the Instituto Clodomiro Picado for evaluating the neutralizing ability of antivenoms in Central America. It includes tests for the neutralization of lethal, haemorrhagic, oedema-forming, myotoxic, coagulant, defibrinating, neurotoxic, proteolytic, phospholipase A2 and hyaluronidase activities. Thus, these assays allow for a complete, detailed evaluation of antivenoms distributed in Central America. Our studies indicate that antivenoms produced in Costa Rica are effective against the Central American venoms tested, whereas other products that are commercially available in the region are less effective in neutralizing the activities of several venoms. Our observations stress the need for rigorous quality control of antivenoms. Universidad de Costa Rica/[]/UCR/Costa Rica International Foundation for Science/[F/1388-1]/IFS/Suecia International Foundation for Science/[F/1388-2]/IFS/Suecia International Foundation for Science/[F/1388-3]/IFS/Suecia International Foundation for Science/[F/0883-1]/IFS/Suecia International Foundation for Science/[F/0883-2]/IFS/Suecia International Foundation for Science/[F/0883-3]/IFS/Suecia International Foundation for Science/[F/0883-4]/IFS/Suecia UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiología
- Published
- 1996
49. Phospholipase A2 myotoxins from Bothrops snake venoms
- Author
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Gutiérrez, José María and Lomonte, Bruno
- Subjects
Snake venom ,615.373 Toxinas y toxoides ,Phospholipase A2 - Abstract
The genus Bothrops is distributed over all Latin America, From Mexico to Argentina, and comprises nearly 31 species of snake. In most of these countries, Bothrops spp. cause the majority of snake bit envenomations, which are characterized by conspicuous local tissue damage including hemorrhage, edema and myonecrosis. In recent years, research efforts to understand the Bothrops venon-induced myonecrosis have resulted in the isolation and characterization of a group of toxic proteins which are mainly responsible for this effect. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiología
- Published
- 1995
50. Immunological studies on BaH1 and BaPI, two hemorrhagic metalloproteinases from the venom of the snake Bothrops asper
- Author
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Rucavado Romero, Alexandra, Borkow, Gadi, Ovadia, Michael, and Gutiérrez, José María
- Subjects
Snake venom ,Immune Sera ,Crotalid Venoms ,Animals ,Metalloendopeptidases ,Bothrops ,Hemorrhage ,complex mixtures - Abstract
No immunological cross-reactivity was observed between BaH1 and BaP1, two hemorrhagic metalloproteinases isolated from B. asper venom, by gel immunodiffusion, Western blotting and neutralization studies. Cross-reactivity was detected with antisera against these toxins in several crotaline and viperine snake venoms by ELISA, whereas no reactivity was observed with either antiserum against the venoms of Bothrops nummifer, Crotalus durissus terrificus, Vipera russelli and several elapid venoms. Antiserum against native BaH1 neutralized hemorrhagic activity of the venoms of B. asper, B. atrox, B. jararaca, Crotalus atrox, C. durissus durissus, Echis carinatus and Trimeresurus flavoviridis, being ineffective against the venoms of Agkistrodon bilineatus and Lachesis muta. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Published
- 1995
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