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Smith CF, Modahl CM, Ceja Galindo D, Larson KY, Maroney SP, Bahrabadi L, Brandehoff NP, Perry BW, McCabe MC, Petras D, Lomonte B, Calvete JJ, Castoe TA, Mackessy SP, Hansen KC, Saviola AJ. Assessing Target Specificity of the Small Molecule Inhibitor MARIMASTAT to Snake Venom Toxins: A Novel Application of Thermal Proteome Profiling. Mol Cell Proteomics 2024; 23:100779. [PMID: 38679388 PMCID: PMC11154231 DOI: 10.1016/j.mcpro.2024.100779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 04/09/2024] [Accepted: 04/25/2024] [Indexed: 05/01/2024] Open
Abstract
New treatments that circumvent the pitfalls of traditional antivenom therapies are critical to address the problem of snakebite globally. Numerous snake venom toxin inhibitors have shown promising cross-species neutralization of medically significant venom toxins in vivo and in vitro. The development of high-throughput approaches for the screening of such inhibitors could accelerate their identification, testing, and implementation and thus holds exciting potential for improving the treatments and outcomes of snakebite envenomation worldwide. Energetics-based proteomic approaches, including thermal proteome profiling and proteome integral solubility alteration (PISA) assays, represent "deep proteomics" methods for high throughput, proteome-wide identification of drug targets and ligands. In the following study, we apply thermal proteome profiling and PISA methods to characterize the interactions between venom toxin proteoforms in Crotalus atrox (Western Diamondback Rattlesnake) and the snake venom metalloprotease (SVMP) inhibitor marimastat. We investigate its venom proteome-wide effects and characterize its interactions with specific SVMP proteoforms, as well as its potential targeting of non-SVMP venom toxin families. We also compare the performance of PISA thermal window and soluble supernatant with insoluble precipitate using two inhibitor concentrations, providing the first demonstration of the utility of a sensitive high-throughput PISA-based approach to assess the direct targets of small molecule inhibitors for snake venom.
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Affiliation(s)
- Cara F Smith
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Cassandra M Modahl
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David Ceja Galindo
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Keira Y Larson
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Sean P Maroney
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Lilyrose Bahrabadi
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Nicklaus P Brandehoff
- Rocky Mountain Poison and Drug Center, Denver Health and Hospital Authority, Denver, Colorado, USA
| | - Blair W Perry
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Maxwell C McCabe
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Daniel Petras
- CMFI Cluster of Excellence, University of Tuebingen, Tuebingen, Germany; Department of Biochemistry, University of California Riverside, Riverside, California, USA
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Juan J Calvete
- Evolutionary and Translational Venomics Laboratory, Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - Todd A Castoe
- Department of Biology, The University of Texas Arlington, Texas, USA
| | - Stephen P Mackessy
- Department of Biological Sciences, University of Northern Colorado, Greeley, Colorado, USA
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA
| | - Anthony J Saviola
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, Colorado, USA.
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2
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Bartlett KE, Hall SR, Rasmussen SA, Crittenden E, Dawson CA, Albulescu LO, Laprade W, Harrison RA, Saviola AJ, Modahl CM, Jenkins TP, Wilkinson MC, Gutiérrez JM, Casewell NR. Dermonecrosis caused by a spitting cobra snakebite results from toxin potentiation and is prevented by the repurposed drug varespladib. Proc Natl Acad Sci U S A 2024; 121:e2315597121. [PMID: 38687786 PMCID: PMC11087757 DOI: 10.1073/pnas.2315597121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 02/26/2024] [Indexed: 05/02/2024] Open
Abstract
Snakebite envenoming is a neglected tropical disease that causes substantial mortality and morbidity globally. The venom of African spitting cobras often causes permanent injury via tissue-destructive dermonecrosis at the bite site, which is ineffectively treated by current antivenoms. To address this therapeutic gap, we identified the etiological venom toxins in Naja nigricollis venom responsible for causing local dermonecrosis. While cytotoxic three-finger toxins were primarily responsible for causing spitting cobra cytotoxicity in cultured keratinocytes, their potentiation by phospholipases A2 toxins was essential to cause dermonecrosis in vivo. This evidence of probable toxin synergism suggests that a single toxin-family inhibiting drug could prevent local envenoming. We show that local injection with the repurposed phospholipase A2-inhibiting drug varespladib significantly prevents local tissue damage caused by several spitting cobra venoms in murine models of envenoming. Our findings therefore provide a therapeutic strategy that may effectively prevent life-changing morbidity caused by snakebite in rural Africa.
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Affiliation(s)
- Keirah E. Bartlett
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Steven R. Hall
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Sean A. Rasmussen
- Department of Pathology and Laboratory Medicine, Queen Elizabeth II Health Sciences Centre and Dalhousie University, Halifax, NSB3H 1V8, Canada
| | - Edouard Crittenden
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Charlotte A. Dawson
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - William Laprade
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens LyngbyDK-2800, Denmark
| | - Robert A. Harrison
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Anthony J. Saviola
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO80045
| | - Cassandra M. Modahl
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - Timothy P. Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens LyngbyDK-2800, Denmark
| | - Mark C. Wilkinson
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José11501–2060, Costa Rica
| | - Nicholas R. Casewell
- Centre for Snakebite Research & Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, LiverpoolL3 5QA, United Kingdom
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3
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Bittenbinder MA, van Thiel J, Cardoso FC, Casewell NR, Gutiérrez JM, Kool J, Vonk FJ. Tissue damaging toxins in snake venoms: mechanisms of action, pathophysiology and treatment strategies. Commun Biol 2024; 7:358. [PMID: 38519650 PMCID: PMC10960010 DOI: 10.1038/s42003-024-06019-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 03/07/2024] [Indexed: 03/25/2024] Open
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.
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Affiliation(s)
- Mátyás A Bittenbinder
- Naturalis Biodiversity Center, 2333 CR, Leiden, The Netherlands
- AIMMS, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands
| | - Jory van Thiel
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, Liverpool, United Kingdom
- Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Howard Hughes Medical Institute and Department of Biology, University of Maryland, College Park, MD, 20742, USA
| | - Fernanda C Cardoso
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
- Centre for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, Liverpool, United Kingdom
| | - José-María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, 11501, Costa Rica.
| | - Jeroen Kool
- AIMMS, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, The Netherlands.
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands.
| | - Freek J Vonk
- Naturalis Biodiversity Center, 2333 CR, Leiden, The Netherlands
- AIMMS, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands
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4
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Uko SO, Malami I, Ibrahim KG, Lawal N, Bello MB, Abubakar MB, Imam MU. Revolutionizing snakebite care with novel antivenoms: Breakthroughs and barriers. Heliyon 2024; 10:e25531. [PMID: 38333815 PMCID: PMC10850593 DOI: 10.1016/j.heliyon.2024.e25531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 01/27/2024] [Accepted: 01/29/2024] [Indexed: 02/10/2024] Open
Abstract
Snakebite envenoming (SBE) is a global public health concern, primarily due to the lack of effective antivenom for treating snakebites inflicted by medically significant venomous snakes prevalent across various geographic locations. The rising demand for safe, cost-effective, and potent snakebite treatments highlights the urgent need to develop alternative therapeutics targeting relevant toxins. This development could provide promising discoveries to create novel recombinant solutions, leveraging human monoclonal antibodies, synthetic peptides and nanobodies. Such technologies as recombinant DNA, peptide and epitope mapping phage display etc) have the potential to exceed the traditional use of equine polyclonal antibodies, which have long been used in antivenom production. Recombinant antivenom can be engineered to target certain toxins that play a critical role in snakebite pathology. This approach has the potential to produce antivenom with improved efficacy and safety profiles. However, there are limitations and challenges associated with these emerging technologies. Therefore, identifying the limitations is critical for overcoming the associated challenges and optimizing the development of recombinant antivenoms. This review is aimed at presenting a thorough overview of diverse technologies used in the development of recombinant antivenom, emphasizing their limitations and offering insights into prospects for advancing recombinant antivenoms.
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Affiliation(s)
- Samuel Odo Uko
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Biochemistry and Molecular Biology, Faculty of Chemical and Life Sciecnes, Usmanu Danfodiyo University Sokoto, Nigeria
| | - Ibrahim Malami
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Pharmacognosy and Ethnopharmacy, Faculty of Pharmaceutical Sciences, Usmanu Danfodiyo University Sokoto, Nigeria
| | - Kasimu Ghandi Ibrahim
- Department of Basic Medical and Dental Sciences, Faculty of Dentistry, Zarqa University, P. O. Box 2000, Zarqa, 13110, Jordan
| | - Nafiu Lawal
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Veterinary Microbiology, Faculty of Veterinary Medicine, Usmanu Danfodiyo University Sokoto, Nigeria
| | - Muhammad Bashir Bello
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Veterinary Microbiology, Faculty of Veterinary Medicine, Usmanu Danfodiyo University Sokoto, Nigeria
- Vaccine Development Unit, Infectious Disease Research Department, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Murtala Bello Abubakar
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Physiology, College of Health Sciences, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Physiology, College of Medicine and Health Sciences, Baze University, Abuja, Nigeria
| | - Mustapha Umar Imam
- Centre for Advanced Medical Research and Training, Usmanu Danfodiyo University Sokoto, Nigeria
- Department of Medical Biochemistry, College of Health Sciences, Usmanu Danfodiyo University Sokoto, Nigeria
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5
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Li A, Yu H, Li R, Yue Y, Yu C, Liu S, Xing R, Li P. Effects of toxin metalloproteinases from jellyfish Nemopilema nomurai nematocyst on the dermal toxicity and potential treatment of jellyfish dermatitis. Int Immunopharmacol 2024; 128:111492. [PMID: 38218009 DOI: 10.1016/j.intimp.2024.111492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/26/2023] [Accepted: 01/03/2024] [Indexed: 01/15/2024]
Abstract
Jellyfish dermatitis is a common medical problem in many countries due to the jellyfish envenomation. However, there are no specific and targeted medications for their treatment. Here we investigated the possible therapeutic effects of metalloproteinase inhibitors on the dermal toxicity of Nemopilema nomurai nematocyst venom (NnNV), a giant venomous jellyfish from China, using the jellyfish dermatitis model, focusing on inflammatory effector molecules during jellyfish envenomation. Metalloproteinase may further stimulate inflammation by promoting oxidative stress in the organism and play key roles by activating MAPK and NF-κB, in the pathogenesis of jellyfish dermatitis. And the metalloproteinase inhibitors batimastat and EDTA disodium salt may treat the Jellyfish dermatitis by inhibiting the metalloproteinase activity in NnNV. These observations suggest that the metalloproteinase components of NnNV make a considerable contribution to dermal toxicity as the inflammation effect molecular, and metalloproteinase inhibitors can be regarded as novel therapeutic medicines in jellyfish envenomation. This study contributes to understanding the mechanism of jellyfish dermatitis and suggests new targets and ideas for the treatment of jellyfish envenomation.
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Affiliation(s)
- Aoyu Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huahua Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China.
| | - Rongfeng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Yang Yue
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Chunlin Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Song Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Ronge Xing
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Pengcheng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
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6
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Clare RH, Dawson CA, Westhorpe A, Albulescu LO, Woodley CM, Mosallam N, Chong DJW, Kool J, Berry NG, O’Neill PM, Casewell NR. Snakebite drug discovery: high-throughput screening to identify novel snake venom metalloproteinase toxin inhibitors. Front Pharmacol 2024; 14:1328950. [PMID: 38273820 PMCID: PMC10808794 DOI: 10.3389/fphar.2023.1328950] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 12/21/2023] [Indexed: 01/27/2024] Open
Abstract
Snakebite envenoming results in ∼100,000 deaths per year, with close to four times as many victims left with life-long sequelae. Current antivenom therapies have several limitations including high cost, variable cross-snake species efficacy and a requirement for intravenous administration in a clinical setting. Next-generation snakebite therapies are being widely investigated with the aim to improve cost, efficacy, and safety. In recent years several small molecule drugs have shown considerable promise for snakebite indication, with oral bioavailability particularly promising for community delivery rapidly after a snakebite. However, only two such drugs have entered clinical development for snakebite. To offset the risk of attrition during clinical trials and to better explore the chemical space for small molecule venom toxin inhibitors, here we describe the first high throughput drug screen against snake venom metalloproteinases (SVMPs)-a pathogenic toxin family responsible for causing haemorrhage and coagulopathy. Following validation of a 384-well fluorescent enzymatic assay, we screened a repurposed drug library of 3,547 compounds against five geographically distinct and toxin variable snake venoms. Our drug screen resulted in the identification of 14 compounds with pan-species inhibitory activity. Following secondary potency testing, four SVMP inhibitors were identified with nanomolar EC50s comparable to the previously identified matrix metalloproteinase inhibitor marimastat and superior to the metal chelator dimercaprol, doubling the current global portfolio of SVMP inhibitors. Following analysis of their chemical structure and ADME properties, two hit-to-lead compounds were identified. These clear starting points for the initiation of medicinal chemistry campaigns provide the basis for the first ever designer snakebite specific small molecules.
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Affiliation(s)
- Rachel H. Clare
- Department of Tropical Disease Biology, Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Charlotte A. Dawson
- Department of Tropical Disease Biology, Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Adam Westhorpe
- Department of Tropical Disease Biology, Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Laura-Oana Albulescu
- Department of Tropical Disease Biology, Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Nada Mosallam
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Daniel J. W. Chong
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Nicholas R. Casewell
- Department of Tropical Disease Biology, Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Albulescu LO, Westhorpe A, Clare RH, Woodley CM, James N, Kool J, Berry NG, O’Neill PM, Casewell NR. Optimizing drug discovery for snakebite envenoming via a high-throughput phospholipase A2 screening platform. Front Pharmacol 2024; 14:1331224. [PMID: 38273832 PMCID: PMC10808766 DOI: 10.3389/fphar.2023.1331224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/19/2023] [Indexed: 01/27/2024] Open
Abstract
Snakebite envenoming is a neglected tropical disease that causes as many as 1.8 million envenomings and 140,000 deaths annually. To address treatment limitations that exist with current antivenoms, the search for small molecule drug-based inhibitors that can be administered as early interventions has recently gained traction. Snake venoms are complex mixtures of proteins, peptides and small molecules and their composition varies substantially between and within snake species. The phospholipases A2 (PLA2) are one of the main pathogenic toxin classes found in medically important viper and elapid snake venoms, yet varespladib, a drug originally developed for the treatment of acute coronary syndrome, remains the only PLA2 inhibitor shown to effectively neutralise venom toxicity in vitro and in vivo, resulting in an extremely limited drug portfolio. Here, we describe a high-throughput drug screen to identify novel PLA2 inhibitors for repurposing as snakebite treatments. We present method optimisation of a 384-well plate, colorimetric, high-throughput screening assay that allowed for a throughput of ∼2,800 drugs per day, and report on the screening of a ∼3,500 post-phase I repurposed drug library against the venom of the Russell's viper, Daboia russelii. We further explore the broad-spectrum inhibitory potential and efficacy of the resulting top hits against a range of medically important snake venoms and demonstrate the utility of our method in determining drug EC50s. Collectively, our findings support the future application of this method to fully explore the chemical space to discover novel PLA2-inhibiting drugs of value for preventing severe pathology caused by snakebite envenoming.
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Affiliation(s)
- Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Adam Westhorpe
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Rachel H. Clare
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Nivya James
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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8
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Thumtecho S, Burlet NJ, Ljungars A, Laustsen AH. Towards better antivenoms: navigating the road to new types of snakebite envenoming therapies. J Venom Anim Toxins Incl Trop Dis 2023; 29:e20230057. [PMID: 38116472 PMCID: PMC10729942 DOI: 10.1590/1678-9199-jvatitd-2023-0057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023] Open
Abstract
Snakebite envenoming is a significant global health challenge, and for over a century, traditional plasma-derived antivenoms from hyperimmunized animals have been the primary treatment against this infliction. However, these antivenoms have several inherent limitations, including the risk of causing adverse reactions when administered to patients, batch-to-batch variation, and high production costs. To address these issues and improve treatment outcomes, the development of new types of antivenoms is crucial. During this development, key aspects such as improved clinical efficacy, enhanced safety profiles, and greater affordability should be in focus. To achieve these goals, modern biotechnological methods can be applied to the discovery and development of therapeutic agents that can neutralize medically important toxins from multiple snake species. This review highlights some of these agents, including monoclonal antibodies, nanobodies, and selected small molecules, that can achieve broad toxin neutralization, have favorable safety profiles, and can be produced on a large scale with standardized manufacturing processes. Considering the inherent strengths and limitations related to the pharmacokinetics of these different agents, a combination of them might be beneficial in the development of new types of antivenom products with improved therapeutic properties. While the implementation of new therapies requires time, it is foreseeable that the application of biotechnological advancements represents a promising trajectory toward the development of improved therapies for snakebite envenoming. As research and development continue to advance, these new products could emerge as the mainstay treatment in the future.
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Affiliation(s)
- Suthimon Thumtecho
- Division of Toxicology, Department of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Nick J. Burlet
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Anne Ljungars
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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9
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Hall SR, Rasmussen SA, Crittenden E, Dawson CA, Bartlett KE, Westhorpe AP, Albulescu LO, Kool J, Gutiérrez JM, Casewell NR. Repurposed drugs and their combinations prevent morbidity-inducing dermonecrosis caused by diverse cytotoxic snake venoms. Nat Commun 2023; 14:7812. [PMID: 38097534 PMCID: PMC10721902 DOI: 10.1038/s41467-023-43510-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 11/11/2023] [Indexed: 12/17/2023] Open
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.
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Affiliation(s)
- Steven R Hall
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Sean A Rasmussen
- Department of Pathology and Laboratory Medicine, Queen Elizabeth II Health Sciences Centre and Dalhousie University, 7th Floor of MacKenzie Building, 5788 University Avenue, Halifax, NS, B3H 1V8, Canada
| | - Edouard Crittenden
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Charlotte A Dawson
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Keirah E Bartlett
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Adam P Westhorpe
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, PO Box 11501-2060, San José, Costa Rica
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
- Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
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10
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Werner RM, Soffa AN. Considerations for the development of a field-based medical device for the administration of adjunctive therapies for snakebite envenoming. Toxicon X 2023; 20:100169. [PMID: 37661997 PMCID: PMC10474190 DOI: 10.1016/j.toxcx.2023.100169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/27/2023] [Accepted: 08/12/2023] [Indexed: 09/05/2023] Open
Abstract
The timely administration of antivenom is the most effective method currently available to reduce the burden of snakebite envenoming (SBE), a neglected tropical disease that most often affects rural agricultural global populations. There is increasing interest in the development of adjunctive small molecule and biologic therapeutics that target the most problematic venom components to bridge the time-gap between initial SBE and the administration antivenom. Unique combinations of these therapeutics could provide relief from the toxic effects of regional groupings of medically relevant snake species. The application a PRISMA/PICO literature search methodology demonstrated an increasing interest in the rapid administration of therapies to improve patient symptoms and outcomes after SBE. Advice from expert interviews and considerations regarding the potential routes of therapy administration, anatomical bite location, and species-specific venom delivery have provided a framework to identify ideal metrics and potential hurdles for the development of a field-based medical device that could be used immediately after SBE to deliver adjunctive therapies. The use of subcutaneous (SC) or intramuscular (IM) injection were identified as potential routes of administration of both small molecule and biologic therapies. The development of a field-based medical device for the delivery of adjunctive SBE therapies presents unique challenges that will require a collaborative and transdisciplinary approach to be successful.
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11
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Gilliam LL, Gilliam J, Samuel SP, Carter RW, Ritchey J, Bulfone T, Gutiérrez JM, Williams DJ, Durkin DM, Stephens SI, Lewin MR. Oral and IV Varespladib Rescue Experiments in Juvenile Pigs with Weakness Induced by Australian and Papuan Oxyuranus scutellatus Venoms. Toxins (Basel) 2023; 15:557. [PMID: 37755983 PMCID: PMC10537020 DOI: 10.3390/toxins15090557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/02/2023] [Accepted: 08/17/2023] [Indexed: 09/28/2023] Open
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.
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Affiliation(s)
- Lyndi L. Gilliam
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA; (L.L.G.); (J.G.); (J.R.)
| | - John Gilliam
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA; (L.L.G.); (J.G.); (J.R.)
| | - Stephen P. Samuel
- Division of Research Ophirex, Inc., Corte Madera, CA 94925, USA; (S.P.S.); (R.W.C.); (S.I.S.)
| | - Rebecca W. Carter
- Division of Research Ophirex, Inc., Corte Madera, CA 94925, USA; (S.P.S.); (R.W.C.); (S.I.S.)
| | - Jerry Ritchey
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA; (L.L.G.); (J.G.); (J.R.)
| | - Tommaso Bulfone
- Center for Exploration and Travel Health, California Academy of Sciences, San Francisco, CA 94118, USA; (T.B.)
- School of Medicine, University of California, San Francisco, CA 94143, USA
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501-2060, Costa Rica;
| | - David J. Williams
- Regulation and Prequalification Department (RPQ) at the World Health Organization (WHO), 1211 Geneva, Switzerland;
| | - Daniela M. Durkin
- Center for Exploration and Travel Health, California Academy of Sciences, San Francisco, CA 94118, USA; (T.B.)
| | - Sally I. Stephens
- Division of Research Ophirex, Inc., Corte Madera, CA 94925, USA; (S.P.S.); (R.W.C.); (S.I.S.)
| | - Matthew R. Lewin
- Division of Research Ophirex, Inc., Corte Madera, CA 94925, USA; (S.P.S.); (R.W.C.); (S.I.S.)
- Center for Exploration and Travel Health, California Academy of Sciences, San Francisco, CA 94118, USA; (T.B.)
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12
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Morales BGDV, Dos Reis MC, Gomes TJDS, Zeferino NA, de Oliveira GA, Zanchi FB. A rational in silico approach to identify inhibitors of Batroxrhagin from Bothrops atrox. J Biomol Struct Dyn 2022; 40:9620-9635. [PMID: 34060428 DOI: 10.1080/07391102.2021.1932597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bothrops atrox venom comprises several types of bioactive molecules, enzymatic and non-enzymatic, among those, Batroxrhagin is the most predominant SVMP P-III enzyme, which are responsible for induction of local and systemic hemorrhage and muscle fibers damage, impairing regeneration. Due to great difficulties in establishing an antibothropic drug, new strategies must be addressed to achieve a more effective and efficient treatment. There are no studies of specific catalytic inhibitors of Batroxrhagin. However, there are in vitro studies that have described similar metalloprotease inhibitors. The inhibitor batimastat was used as a leading compound for the search and selection of similar candidates. This molecule is widely cited as a metalloprotease inhibitor and as an antimetastatic. In addition to batimastat-like molecules, four other reported metalloprotease inhibitors were included to compose the study's positive control group. Hence, 580 molecules were tested. The three-dimensional structure of B. atrox Batroxrhagin was predicted based on homologous structures using Modeller 9.20. Molecular docking calculation was performed using Autodock 4.2 and molecular surfaces and interactions were analyzed using Biovia/Discovery Studio 2017. Among 576 molecules, 42 similar to batismast resulted in a better energy of interaction than all positive controls, including batimastat itself. The batimastat-like molecules with lowest energy and positive controls were subjected to molecular dynamics for 30 ns in Gromacs 2019.4. This batimastat-like molecule produced better stability among all the Batroxrhagin-ligand complexes analyzed. Overall, the proposed compounds present justifiable evidence for future in vitro tests aiming to inhibit Batroxrhagin. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Bruno Gildo Dalla Vecchia Morales
- Laboratório de Bioinformática e Química Medicinal, Fundação Oswaldo Cruz Rondônia, Porto Velho-RO, Brazil.,Programa de Pós-Graduação em Biologia Experimental, Universidade Federal de Rondônia (UNIR), Porto Velho-RO, Brazil.,FIOCRUZ Rondônia, Porto Velho-RO, Brazil
| | - Marlon Chaves Dos Reis
- Laboratório de Bioinformática e Química Medicinal, Fundação Oswaldo Cruz Rondônia, Porto Velho-RO, Brazil.,Faculdades Integradas Aparício Carvalho/FIMCA, Porto Velho-RO, Brazil
| | | | - Nabia Azevedo Zeferino
- Laboratório de Bioinformática e Química Medicinal, Fundação Oswaldo Cruz Rondônia, Porto Velho-RO, Brazil.,Faculdades Integradas Aparício Carvalho/FIMCA, Porto Velho-RO, Brazil
| | - George Azevedo de Oliveira
- Laboratório de Bioinformática e Química Medicinal, Fundação Oswaldo Cruz Rondônia, Porto Velho-RO, Brazil.,Programa de Doutorado em Ciências - Cooperação IOC/Fiocruz Rondônia: Biologia Computacional e Sistemas (BCS), Porto Velho-RO, Brazil
| | - Fernando Berton Zanchi
- Laboratório de Bioinformática e Química Medicinal, Fundação Oswaldo Cruz Rondônia, Porto Velho-RO, Brazil.,Programa de Pós-Graduação em Biologia Experimental, Universidade Federal de Rondônia (UNIR), Porto Velho-RO, Brazil.,FIOCRUZ Rondônia, Porto Velho-RO, Brazil.,Programa de Doutorado em Ciências - Cooperação IOC/Fiocruz Rondônia: Biologia Computacional e Sistemas (BCS), Porto Velho-RO, Brazil.,Instituto Nacional de Epidemiologia na Amazônia Ocidental - EPIAMO, Porto Velho-RO, Brazil
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13
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Arrahman A, Kazandjian TD, Still KBM, Slagboom J, Somsen GW, Vonk FJ, Casewell NR, Kool J. A Combined Bioassay and Nanofractionation Approach to Investigate the Anticoagulant Toxins of Mamba and Cobra Venoms and Their Inhibition by Varespladib. Toxins (Basel) 2022; 14:736. [PMID: 36355986 PMCID: PMC9695013 DOI: 10.3390/toxins14110736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 01/26/2023] Open
Abstract
Envenomation by elapid snakes primarily results in neurotoxic symptoms and, consequently, are the primary focus of therapeutic research concerning such venoms. However, mounting evidence suggests these venoms can additionally cause coagulopathic symptoms, as demonstrated by some Asian elapids and African spitting cobras. This study sought to investigate the coagulopathic potential of venoms from medically important elapids of the genera Naja (true cobras), Hemachatus (rinkhals), and Dendroaspis (mambas). Crude venoms were bioassayed for coagulant effects using a plasma coagulation assay before RPLC/MS was used to separate and identify venom toxins in parallel with a nanofractionation module. Subsequently, coagulation bioassays were performed on the nanofractionated toxins, along with in-solution tryptic digestion and proteomics analysis. These experiments were then repeated on both crude venoms and on the nanofractionated venom toxins with the addition of either the phospholipase A2 (PLA2) inhibitor varespladib or the snake venom metalloproteinase (SVMP) inhibitor marimastat. Our results demonstrate that various African elapid venoms have an anticoagulant effect, and that this activity is significantly reduced for cobra venoms by the addition of varespladib, though this inhibitor had no effect against anticoagulation caused by mamba venoms. Marimastat showed limited capacity to reduce anticoagulation in elapids, affecting only N. haje and H. haemachatus venom at higher doses. Proteomic analysis of nanofractionated toxins revealed that the anticoagulant toxins in cobra venoms were both acidic and basic PLA2s, while the causative toxins in mamba venoms remain uncertain. This implies that while PLA2 inhibitors such as varespladib and metalloproteinase inhibitors such as marimastat are viable candidates for novel snakebite treatments, they are not likely to be effective against mamba envenomings.
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Affiliation(s)
- Arif Arrahman
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands
- Faculty of Pharmacy, Universitas Indonesia, Kampus Baru UI, Depok 16424, Indonesia
| | - Taline D. Kazandjian
- Centre for Snakebite Research and Interventions. Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Kristina B. M. Still
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands
| | - Julien Slagboom
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands
| | - Govert W. Somsen
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands
| | - Freek J. Vonk
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Naturalis Biodiversity Centre, Darwinweg 2, 2333 CR Leiden, The Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions. Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Jeroen Kool
- Division of Bioanalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands
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14
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Offor BC, Muller B, Piater LA. A Review of the Proteomic Profiling of African Viperidae and Elapidae Snake Venoms and Their Antivenom Neutralisation. Toxins (Basel) 2022; 14:toxins14110723. [PMID: 36355973 PMCID: PMC9694588 DOI: 10.3390/toxins14110723] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/17/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022] Open
Abstract
Snakebite envenoming is a neglected tropical disease (NTD) that results from the injection of snake venom of a venomous snake into animals and humans. In Africa (mainly in sub-Saharan Africa), over 100,000 envenomings and over 10,000 deaths per annum from snakebite have been reported. Difficulties in snakebite prevention and antivenom treatment are believed to result from a lack of epidemiological data and underestimated figures on snakebite envenoming-related morbidity and mortality. There are species- and genus-specific variations associated with snake venoms in Africa and across the globe. These variations contribute massively to diverse differences in venom toxicity and pathogenicity that can undermine the efficacy of adopted antivenom therapies used in the treatment of snakebite envenoming. There is a need to profile all snake venom proteins of medically important venomous snakes endemic to Africa. This is anticipated to help in the development of safer and more effective antivenoms for the treatment of snakebite envenoming within the continent. In this review, the proteomes of 34 snake venoms from the most medically important snakes in Africa, namely the Viperidae and Elipdae, were extracted from the literature. The toxin families were grouped into dominant, secondary, minor, and others based on the abundance of the protein families in the venom proteomes. The Viperidae venom proteome was dominated by snake venom metalloproteinases (SVMPs-41%), snake venom serine proteases (SVSPs-16%), and phospholipase A2 (PLA2-17%) protein families, while three-finger toxins (3FTxs-66%) and PLA2s (16%) dominated those of the Elapidae. We further review the neutralisation of these snake venoms by selected antivenoms widely used within the African continent. The profiling of African snake venom proteomes will aid in the development of effective antivenom against snakebite envenoming and, additionally, could possibly reveal therapeutic applications of snake venom proteins.
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Affiliation(s)
- Benedict C. Offor
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park 2006, South Africa
| | - Beric Muller
- South Africa Venom Suppliers CC, Louis Trichardt 0920, South Africa
| | - Lizelle A. Piater
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park 2006, South Africa
- Correspondence: ; Tel.: +27-11-559-2403
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15
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Bibliometric Analysis of Literature in Snake Venom-Related Research Worldwide (1933–2022). Animals (Basel) 2022; 12:ani12162058. [PMID: 36009648 PMCID: PMC9405337 DOI: 10.3390/ani12162058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/03/2022] [Accepted: 08/09/2022] [Indexed: 11/29/2022] Open
Abstract
Simple Summary Around the world, snake envenomation poses a serious health risk. Proteins with pharmacological effects are present in snake venom. Recent studies elaborate snake venom and its potential application, including as a cancer drug and antibacterial substances. Our study aimed to analyze the global profile of the literature in snake venom research from documents indexed in the Scopus database between 1933 and 2022. In total, 2999 documents were published with Brazil showing the highest productivity. Antivenom, proteomics, and transcriptomics are emerging as hot topics on a global scale. The present study offers a distinctive overview of snake venom research conducted worldwide. Abstract Snake envenomation is a severe economic and health concern affecting countries worldwide. Snake venom carries a wide variety of small peptides and proteins with various immunological and pharmacological properties. A few key research areas related to snake venom, including its applications in treating cancer and eradicating antibiotic-resistant bacteria, have been gaining significant attention in recent years. The goal of the current study was to analyze the global profile of literature in snake venom research. This study presents a bibliometric review of snake venom-related research documents indexed in the Scopus database between 1933 and 2022. The overall number of documents published on a global scale was 2999, with an average annual production of 34 documents. Brazil produced the highest number of documents (n = 729), followed by the United States (n = 548), Australia (n = 240), and Costa Rica (n = 235). Since 1963, the number of publications has been steadily increasing globally. At a worldwide level, antivenom, proteomics, and transcriptomics are growing hot issues for research in this field. The current research provides a unique overview of snake venom research at global level from 1933 through 2022, and it may be beneficial in guiding future research.
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16
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Gómez A, Sánchez A, Durán G, Cordero D, Segura Á, Vargas M, Solano D, Herrera M, Chaves-Araya S, Villalta M, Sánchez M, Arguedas M, Díaz C, Gutiérrez JM, León G. Intrageneric cross-reactivity of monospecific rabbit antisera against venoms of the medically most important Bitis spp. and Echis spp. African snakes. PLoS Negl Trop Dis 2022; 16:e0010643. [PMID: 35960772 PMCID: PMC9374258 DOI: 10.1371/journal.pntd.0010643] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 07/08/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Snakebite envenomation exerts a heavy toll in sub-Saharan Africa. The design and production of effective polyspecific antivenoms for this region demand a better understanding of the immunological characteristics of the different venoms from the most medically important snakes, to select the most appropriate venom combinations for generating antivenoms of wide neutralizing scope. Bitis spp. and Echis spp. represent the most important viperid snake genera in Africa. METHODOLOGY/PRINCIPAL FINDINGS Eight rabbit-derived monospecific antisera were raised against the venoms of four species of Bitis spp. and four species of Echis spp. The effects of immunization in the rabbits were assessed, as well as the development of antibody titers, as judged by immunochemical assays and neutralization of lethal, hemorrhagic, and in vitro coagulant effects. At the end of immunizations, local and pulmonary hemorrhage, together with slight increments in the plasma activity of creatine kinase (CK), were observed owing to the action of hemorrhagic and myotoxic venom components. Immunologic analyses revealed a considerable extent of cross-reactivity of monospecific antisera against heterologous venoms within each genus, although some antisera provided a more extensive cross-reactivity than others. The venoms that generated antisera with the broadest coverage were those of Bitis gabonica and B. rhinoceros within Bitis spp. and Echis leucogaster within Echis spp. CONCLUSIONS/SIGNIFICANCE The methodology followed in this study provides a rational basis for the selection of the best combination of venoms for generating antivenoms of high cross-reactivity against viperid venoms in sub-Saharan Africa. Results suggest that the venoms of B. gabonica, B. rhinoceros, and E. leucogaster generate antisera with the broadest cross-reactivity within their genera. These experimental results in rabbits need to be translated to large animals used in antivenom production to assess whether these predictions are reproduced in horses or sheep.
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Affiliation(s)
- Aarón Gómez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Andrés Sánchez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Gina Durán
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Daniel Cordero
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Álvaro Segura
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Mariángela Vargas
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Daniela Solano
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - María Herrera
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Stephanie Chaves-Araya
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Mauren Villalta
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Melvin Sánchez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Mauricio Arguedas
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Cecilia Díaz
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Guillermo León
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
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Menzies SK, Clare RH, Xie C, Westhorpe A, Hall SR, Edge RJ, Alsolaiss J, Crittenden E, Marriott AE, Harrison RA, Kool J, Casewell NR. In vitro and in vivo preclinical venom inhibition assays identify metalloproteinase inhibiting drugs as potential future treatments for snakebite envenoming by Dispholidus typus. Toxicon X 2022; 14:100118. [PMID: 35321116 PMCID: PMC8935517 DOI: 10.1016/j.toxcx.2022.100118] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/18/2022] [Accepted: 03/07/2022] [Indexed: 11/23/2022] Open
Abstract
Snakebite envenoming affects more than 250,000 people annually in sub-Saharan Africa. Envenoming by Dispholidus typus (boomslang) results in venom-induced consumption coagulopathy (VICC), whereby highly abundant prothrombin-activating snake venom metalloproteinases (SVMPs) consume clotting factors and deplete fibrinogen. The only available treatment for D. typus envenoming is the monovalent SAIMR Boomslang antivenom. Treatment options are urgently required because this antivenom is often difficult to source and, at US$6000/vial, typically unaffordable for most snakebite patients. We therefore investigated the in vitro and in vivo preclinical efficacy of four SVMP inhibitors to neutralise the effects of D. typus venom; the matrix metalloproteinase inhibitors marimastat and prinomastat, and the metal chelators dimercaprol and DMPS. The venom of D. typus exhibited an SVMP-driven procoagulant phenotype in vitro. Marimastat and prinomastat demonstrated equipotent inhibition of the SVMP-mediated procoagulant activity of the venom in vitro, whereas dimercaprol and DMPS showed considerably lower potency. However, when tested in preclinical murine models of envenoming using mixed sex CD1 mice, DMPS and marimastat demonstrated partial protection against venom lethality, demonstrated by prolonged survival times of experimental animals, whereas dimercaprol and prinomastat failed to confer any protection at the doses tested. The preclinical results presented here demonstrate that DMPS and marimastat show potential as novel small molecule-based therapeutics for D. typus snakebite envenoming. These two drugs have been previously shown to be effective against Echis ocellatus VICC in preclinical models, and thus we conclude that marimastat and DMPS should be further explored as potentially valuable early intervention therapeutics to broadly treat VICC following snakebite envenoming in sub-Saharan Africa.
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Affiliation(s)
- Stefanie K. Menzies
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Rachel H. Clare
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Chunfang Xie
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, the Netherlands
| | - Adam Westhorpe
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Steven R. Hall
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Rebecca J. Edge
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Jaffer Alsolaiss
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Edouard Crittenden
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Amy E. Marriott
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Robert A. Harrison
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
| | - Jeroen Kool
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, the Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, England, UK
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Varespladib (LY315920) rescued mice from fatal neurotoxicity caused by venoms of five major Asiatic kraits (Bungarus spp.) in an experimental envenoming and rescue model. Acta Trop 2022; 227:106289. [PMID: 34929179 DOI: 10.1016/j.actatropica.2021.106289] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 12/16/2021] [Accepted: 12/16/2021] [Indexed: 11/23/2022]
Abstract
The venoms of Asiatic kraits (Bungarus spp.) contain various neurotoxic phospholipases A2 (beta-bungarotoxins) which can irreversibly damage motor nerve terminals, resulting in rapidly fatal suffocation by respiratory muscle paralysis or oral airway obstruction. Hence, there is a need of adjunct therapy at the pre-hospital stage to prevent or delay the onset of neurotoxicity, so that antivenom can be given within golden hour before the envenoming becomes antivenom-resistant. This study investigated the efficacy of varespladib, a small molecule PLA2 (phospholipase A2) inhibitor, given as a bolus subcutaneously upon the onset of krait venom-induced paralysis in a mouse experimental envenoming and rescue model, where the severity of neurotoxicity was scored and the survival rate was monitored over 24 h. Varespladib at 10 mg/kg effectively alleviated the neurotoxicity of Bungarus sindanus, Bungarus multicinctus and Bungarus fasciatus venoms, and rescued all mice from venom-induced lethality (100% survival). Varespladib at this dose, however, only partially reduced the neurotoxicity of Bungarus caeruleus and Bungarus candidus venoms, while all challenged mice were dead by 23 h (B. caeruleus) and 12 h (B. candidus). An increased dose of varespladib at 20 mg/kg markedly abated the venom neurotoxicity past 8 h of envenoming, and protected the mice from venom lethality (B. caeruleus: 75% survival; B. candidus: 100% survival). The finding is consistent with previous studies which demonstrated varespladib's inhibitory effect against some snake venoms. The findings suggest varespladib could be repurposed as an emergency drug for prevention or rescue (if given early enough) from the acute, neurotoxic envenoming syndromes caused by various major krait species in Asia.
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Abstract
SNAKE ENVENOMATION REPRESENTS AN IMPORTANT HEALTH PROBLEM IN much of the world. In 2009, it was recognized by the World Health Organization (WHO) as a neglected tropical disease, and in 2017, it was elevated into Category A of the Neglected Tropical Diseases list, further expanding access to funding for research and antivenoms. However, snake envenomation occurs in both tropical and temperate climates and on all continents except Antarctica. Worldwide, the estimated number of annual deaths due to snake envenomation (80,000 to 130,000) is similar to the estimate for drug-resistant tuberculosis and for multiple myeloma., In countries with adequate resources, deaths are infrequent (e.g., <6 deaths per year in the United States, despite the occurrence of 7000 to 8000 bites), but in countries without adequate resources, deaths may number in the tens of thousands. Venomous snakes kept as pets are not rare, and physicians anywhere might be called on to manage envenomation by a nonnative snake. Important advances have occurred in our understanding of the biology of venom and the management of snake envenomation since this topic was last addressed in the Journal two decades ago. For the general provider, it is important to understand the spectrum of snake envenomation effects and approaches to management and to obtain specific guidance, when needed.
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Affiliation(s)
- Steven A Seifert
- From the Department of Emergency Medicine and the New Mexico Poison and Drug Information Center, University of New Mexico Health Sciences Center, Albuquerque (S.A.S.); the Department of Internal Medicine, University of Nebraska Medical Center, Omaha (J.O.A.); and the National Natural Toxins Research Center and the Department of Chemistry, Texas A&M University-Kingsville, Kingsville (E.E.S.)
| | - James O Armitage
- From the Department of Emergency Medicine and the New Mexico Poison and Drug Information Center, University of New Mexico Health Sciences Center, Albuquerque (S.A.S.); the Department of Internal Medicine, University of Nebraska Medical Center, Omaha (J.O.A.); and the National Natural Toxins Research Center and the Department of Chemistry, Texas A&M University-Kingsville, Kingsville (E.E.S.)
| | - Elda E Sanchez
- From the Department of Emergency Medicine and the New Mexico Poison and Drug Information Center, University of New Mexico Health Sciences Center, Albuquerque (S.A.S.); the Department of Internal Medicine, University of Nebraska Medical Center, Omaha (J.O.A.); and the National Natural Toxins Research Center and the Department of Chemistry, Texas A&M University-Kingsville, Kingsville (E.E.S.)
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Puzari U, Fernandes PA, Mukherjee AK. Advances in the Therapeutic Application of Small-Molecule Inhibitors and Repurposed Drugs against Snakebite. J Med Chem 2021; 64:13938-13979. [PMID: 34565143 DOI: 10.1021/acs.jmedchem.1c00266] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The World Health Organization has declared snakebite as a neglected tropical disease. Antivenom administration is the sole therapy against venomous snakebite; however, several limitations of this therapy reinforce the dire need for an alternative and/or additional treatment against envenomation. Inhibitors against snake venoms have been explored from natural resources and are synthesized in the laboratory; however, repurposing of small-molecule therapeutics (SMTs) against the principal toxins of snake venoms to inhibit their lethality and/or obnoxious effect of envenomation has been garnering greater attention owing to their established pharmacokinetic properties, low-risk attributes, cost-effectiveness, ease of administration, and storage stability. Nevertheless, SMTs are yet to be approved and commercialized for snakebite treatment. Therefore, we have systematically reviewed and critically analyzed the scenario of small synthetic inhibitors and repurposed drugs against snake envenomation from 2005 to date and proposed novel approaches and commercialization strategies for the development of efficacious therapies against snake envenomation.
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Affiliation(s)
- Upasana Puzari
- Department of Molecular Biology and Biotechnology, School of Sciences, Tezpur University, Tezpur-784028, Assam, India
| | - Pedro Alexandrino Fernandes
- LAQV@REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua Do Campo Alegre S/N, 4169-007 Porto, Portugal
| | - Ashis K Mukherjee
- Department of Molecular Biology and Biotechnology, School of Sciences, Tezpur University, Tezpur-784028, Assam, India.,Institute of Advanced Study in Science and Technology, Vigyan Path Garchuk, Paschim Boragaon, Guwahati-781035, Assam, India
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21
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Yusuf AJ, Aleku GA, Bello UR, Liman DU. Prospects and Challenges of Developing Plant-Derived Snake Antivenin Natural Products: A Focus on West Africa. ChemMedChem 2021; 16:3635-3648. [PMID: 34585514 DOI: 10.1002/cmdc.202100478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 09/23/2021] [Indexed: 11/06/2022]
Abstract
Snakebite envenomation (SBE) is an important public health issue that is now receiving renewed attention following its reclassification as a Neglected Tropical Disease (NTD). Most incidences occur in rural areas of resource-limited countries, as such, timely and appropriate medical care for SBE is often inaccessible. The administration of anti-snake venom serum (ASV) is the only effective definitive treatment of SBE, but treatment failure to available ASVs is not uncommon. Emerging evidence highlights the potential of small-molecule compounds as inhibitors against toxins of snake venom. This presents an encouraging prospect to develop an alternative therapeutic option for the treatment SBE, that may be amenable for use at the point of care in resource-constraint settings. In view of the pivotal role of natural products in modern drug discovery programmes, there is considerable interest in ethno-pharmacological mining of medicinal plants and plant-derived medicinal compounds toward developing novel snake venom-neutralising therapeutics. In this review, we compile a collection of medicinal plants used in the treatment of SBE in West Africa and highlight their promise as potential botanical drugs or as sources of novel small-molecule compounds for the treatment of SBE. The challenges that must be surmounted to bring this to fruition including the need for (sub) regional collaboration have been discussed.
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Affiliation(s)
- Amina J Yusuf
- Department of Pharmaceutical & Medicinal Chemistry, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Godwin A Aleku
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
| | - Usman Rabiu Bello
- Biotechnology unit, Department of Life Sciences, Mewar University, Gangrar, Chittorgarh, Rajasthan, India
| | - Dahiru Umar Liman
- Department of Pharmaceutical & Medicinal Chemistry, Usmanu Danfodiyo University, Sokoto, Nigeria
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22
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Nakamoto M, Escalante T, Gutiérrez JM, Shea KJ. A Biomimetic of Endogenous Tissue Inhibitors of Metalloproteinases: Inhibition Mechanism and Contribution of Composition, Polymer Size, and Shape to the Inhibitory Effect. NANO LETTERS 2021; 21:5663-5670. [PMID: 34181420 DOI: 10.1021/acs.nanolett.1c01357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A biomimetic of endogenous tissue inhibitors of metalloproteinases (TIMPs) was engineered by introducing three binding elements to a synthetic tetrapolymer. We evaluated the contribution of composition, size, and shape of the TIMP-mimicking polymers to the inhibition of BaP1, a P-I class snake venom metalloproteinase (SVMP). Inhibition was achieved when the size of the linear polymer (LP) was comparable to or greater than that of the enzyme, indicating the efficacy requires binding to a significant portion of the enzyme surface in the vicinity of the active site. The efficacy of a low cross-linked polymer hydrogel nanoparticle (NP) of substantially greater molecular weight was comparable to that of the LPs despite differences in size and shape, an important finding for in vivo applications. The abiotic TIMP was effective against two classes of SVMPs in whole snake venom. The results can serve as a design principle for biomimetic polymer inhibitors of enzymes.
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Affiliation(s)
- Masahiko Nakamoto
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Teresa Escalante
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501, Costa Rica
| | - José M Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501, Costa Rica
| | - Kenneth J Shea
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
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23
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Gutiérrez JM, Albulescu LO, Clare RH, Casewell NR, Abd El-Aziz TM, Escalante T, Rucavado A. The Search for Natural and Synthetic Inhibitors That Would Complement Antivenoms as Therapeutics for Snakebite Envenoming. Toxins (Basel) 2021; 13:451. [PMID: 34209691 PMCID: PMC8309910 DOI: 10.3390/toxins13070451] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/23/2021] [Accepted: 06/27/2021] [Indexed: 12/28/2022] Open
Abstract
A global strategy, under the coordination of the World Health Organization, is being unfolded to reduce the impact of snakebite envenoming. One of the pillars of this strategy is to ensure safe and effective treatments. The mainstay in the therapy of snakebite envenoming is the administration of animal-derived antivenoms. In addition, new therapeutic options are being explored, including recombinant antibodies and natural and synthetic toxin inhibitors. In this review, snake venom toxins are classified in terms of their abundance and toxicity, and priority actions are being proposed in the search for snake venom metalloproteinase (SVMP), phospholipase A2 (PLA2), three-finger toxin (3FTx), and serine proteinase (SVSP) inhibitors. Natural inhibitors include compounds isolated from plants, animal sera, and mast cells, whereas synthetic inhibitors comprise a wide range of molecules of a variable chemical nature. Some of the most promising inhibitors, especially SVMP and PLA2 inhibitors, have been developed for other diseases and are being repurposed for snakebite envenoming. In addition, the search for drugs aimed at controlling endogenous processes generated in the course of envenoming is being pursued. The present review summarizes some of the most promising developments in this field and discusses issues that need to be considered for the effective translation of this knowledge to improve therapies for tackling snakebite envenoming.
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Affiliation(s)
- José María Gutiérrez
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, San José 11501, Costa Rica; (T.E.); (A.R.)
| | - Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (L.-O.A.); (R.H.C.); (N.R.C.)
| | - Rachel H. Clare
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (L.-O.A.); (R.H.C.); (N.R.C.)
| | - Nicholas R. Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (L.-O.A.); (R.H.C.); (N.R.C.)
| | - Tarek Mohamed Abd El-Aziz
- Zoology Department, Faculty of Science, Minia University, El-Minia 61519, Egypt;
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
| | - Teresa Escalante
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, San José 11501, Costa Rica; (T.E.); (A.R.)
| | - Alexandra Rucavado
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, San José 11501, Costa Rica; (T.E.); (A.R.)
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24
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Clare RH, Hall SR, Patel RN, Casewell NR. Small Molecule Drug Discovery for Neglected Tropical Snakebite. Trends Pharmacol Sci 2021; 42:340-353. [DOI: 10.1016/j.tips.2021.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 12/31/2022]
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Patra A, Mukherjee AK. Assessment of snakebite burdens, clinical features of envenomation, and strategies to improve snakebite management in Vietnam. Acta Trop 2021; 216:105833. [PMID: 33485869 DOI: 10.1016/j.actatropica.2021.105833] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 12/16/2022]
Abstract
The sheer paucity of scientific documentation of herpetofauna in Vietnam and the rudimentary healthcare response to snakebite have stimulated this review. Over six decades of data culled from public data bases and search engines, have been used to assess snakebite burdens, clinical features of envenomation, and strategies for snakebite management in Vietnam. In addition, biochemical and proteomic analyses to decipher venom composition, rapid analytical techniques to be used for clinical diagnosis of snakebite in Vietnam have been discussed in detail. The assessment of efficacy, safety, and quality of commercial antivenom produced in Vietnam and improvement of antivenom production to meet the national requirement has been critically examined. It is apparent that snake bite incidence in Vietnam is exacerbated by mismatch in demand and supply of antivenom therapy, insufficient medical facilities, preference for traditional healers and poor management of clinical records. The impediments arising from geographical and species-specific variation in venom composition can be overcome by the 'Omics approach', and scientific documentation of pathophysiological manifestations post envenomation. The development of next generation of therapeutics, encouraging clinical research, novel approaches and social awareness against snakebite and its treatments have been suggested to significantly reduce the snakebite mortality and morbidity in this region.
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Affiliation(s)
- Aparup Patra
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, Assam, India.
| | - Ashis K Mukherjee
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, Assam, India; Institute of Advanced Study in Science and Technology, Vigyan Path Garchuk, Paschim Boragaon, Guwahati, Assam 781035, India.
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Gutiérrez JM, Vargas M, Segura Á, Herrera M, Villalta M, Solano G, Sánchez A, Herrera C, León G. In Vitro Tests for Assessing the Neutralizing Ability of Snake Antivenoms: Toward the 3Rs Principles. Front Immunol 2021; 11:617429. [PMID: 33505403 PMCID: PMC7829219 DOI: 10.3389/fimmu.2020.617429] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 11/23/2020] [Indexed: 12/24/2022] Open
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 A2), (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.
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Affiliation(s)
| | - Mariángela Vargas
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Álvaro Segura
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - María Herrera
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Mauren Villalta
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Gabriela Solano
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Andrés Sánchez
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Cristina Herrera
- Facultad de Farmacia, Universidad de Costa Rica, San José, Costa Rica
| | - Guillermo León
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
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Chowdhury A, Zdenek CN, Dobson JS, Bourke LA, Soria R, Fry BG. Clinical implications of differential procoagulant toxicity of the palearctic viperid genus Macrovipera, and the relative neutralization efficacy of antivenoms and enzyme inhibitors. Toxicol Lett 2021; 340:77-88. [PMID: 33412251 DOI: 10.1016/j.toxlet.2020.12.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/22/2020] [Accepted: 12/29/2020] [Indexed: 12/20/2022]
Abstract
Species within the viperid genus Macrovipera are some of the most dangerous snakes in the Eurasian region, injecting copious amounts of potent venom. Despite their medical importance, the pathophysiological actions of their venoms have been neglected. Particularly poorly known are the coagulotoxic effects and thus the underlying mechanisms of lethal coagulopathy. In order to fill this knowledge gap, we ascertained the effects of venom upon human plasma for Macrovipera lebetina cernovi, M. l. lebetina, M. l. obtusa, M. l. turanica, and M. schweizeri using diverse coagulation analysing protocols. All five were extremely potent in their ability to promote clotting but varied in their relative activation of Factor X, being equipotent in this study to the venom of the better studied, and lethal, species Daboia russelii. The Insoserp European viper antivenom was shown to be highly effective against all the Macrovipera venoms, but performed poorly against the D. russelii venom. Reciprocally, while Daboia antivenoms performed well against D. russelii venom, they failed against Macrovipera venom. Thus despite the two genera sharing a venom phenotype (Factor X activation) driven by the same toxin type (P-IIId snake venom metalloproteases), the surface biochemistries of the toxins differed significantly enough to impede antivenom cross- neutralization. The differences in venom biochemistry were reflected in coagulation co-factor dependence. While both genera were absolutely dependent upon calcium for the activation of Factor X, dependence upon phospholipid varied. The Macrovipera venoms had low levels of dependence upon phospholipid while the Daboia venom was three times more dependent upon phospholipid for the activation of Factor X. This suggests that the sites on the molecular surface responsible for phospholipid dependence, are the same differential sites that prevent inter-genera antivenom cross- neutralization. Due to cold-chain requirements, antivenoms may not be stocked in rural settings where the need is at the greatest. Thus we tested the efficacy of enzyme inhibitor Prinomastat as a field-deployable treatment to stabilise patients while being transported to antivenom stocks, and showed that it was extremely effective in blocking the Factor X activating pathophysiological actions. Marimastat however was less effective. These results thus not only shed light on the coagulopathic mechanisms of Macrovipera venoms, but also provide data critical for evidence-based design of snakebite management strategies.
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Affiliation(s)
- Abhinandan Chowdhury
- Toxin Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, 4072, Australia; Department of Biochemistry & Microbiology, North South University, Dhaka, 1229, Bangladesh
| | - Christina N Zdenek
- Toxin Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, 4072, Australia
| | - James S Dobson
- Toxin Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Lachlan A Bourke
- Toxin Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Raul Soria
- Inosan Biopharma, S.A. Arbea Campus Empresarial, Edificio 2, Planta 2, Carretera Fuencarral a Alcobendas, Km 3.8, 28108, Madrid, Spain
| | - Bryan G Fry
- Toxin Evolution Lab, School of Biological Science, University of Queensland, St. Lucia, QLD, 4072, Australia.
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Albulescu LO, Xie C, Ainsworth S, Alsolaiss J, Crittenden E, Dawson CA, Softley R, Bartlett KE, Harrison RA, Kool J, Casewell NR. A therapeutic combination of two small molecule toxin inhibitors provides broad preclinical efficacy against viper snakebite. Nat Commun 2020; 11:6094. [PMID: 33323937 PMCID: PMC7738508 DOI: 10.1038/s41467-020-19981-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 11/11/2020] [Indexed: 01/21/2023] Open
Abstract
Snakebite is a medical emergency causing high mortality and morbidity in rural tropical communities that typically experience delayed access to unaffordable therapeutics. Viperid snakes are responsible for the majority of envenomings, but extensive interspecific variation in venom composition dictates that different antivenom treatments are used in different parts of the world, resulting in clinical and financial snakebite management challenges. Here, we show that a number of repurposed Phase 2-approved small molecules are capable of broadly neutralizing distinct viper venom bioactivities in vitro by inhibiting different enzymatic toxin families. Furthermore, using murine in vivo models of envenoming, we demonstrate that a single dose of a rationally-selected dual inhibitor combination consisting of marimastat and varespladib prevents murine lethality caused by venom from the most medically-important vipers of Africa, South Asia and Central America. Our findings support the translation of combinations of repurposed small molecule-based toxin inhibitors as broad-spectrum therapeutics for snakebite.
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Affiliation(s)
- Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Chunfang Xie
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands
| | - Stuart Ainsworth
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Jaffer Alsolaiss
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Edouard Crittenden
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Charlotte A Dawson
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Rowan Softley
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Keirah E Bartlett
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Robert A Harrison
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH, Amsterdam, The Netherlands
| | - Nicholas R Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK.
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK.
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Alangode A, Rajan K, Nair BG. Snake antivenom: Challenges and alternate approaches. Biochem Pharmacol 2020; 181:114135. [DOI: 10.1016/j.bcp.2020.114135] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/25/2020] [Accepted: 07/01/2020] [Indexed: 02/06/2023]
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Fontana Oliveira IC, Gutiérrez JM, Lewin MR, Oshima-Franco Y. Varespladib (LY315920) inhibits neuromuscular blockade induced by Oxyuranus scutellatus venom in a nerve-muscle preparation. Toxicon 2020; 187:101-104. [PMID: 32889027 DOI: 10.1016/j.toxicon.2020.08.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/08/2020] [Accepted: 08/30/2020] [Indexed: 11/28/2022]
Abstract
The phospholipase A2 (PLA2) inhibitors varespladib (LY315920) and its orally available derivative methyl-varespladib (LY333013) have been proposed as potential therapies for the treatment of snakebite envenomings in which toxicity depends on the action of PLA2s. In this study, the ability of LY315920 to abrogate the effect of the potent neurotoxic venom of Oxyuranus scutellatus (taipan) was assessed using the mouse phrenic nerve-diaphragm preparation. LY315920 inhibited the venom when (a) incubated with venom before addition to the medium; (b) added to the medium before addition of venom, and; (c) added to the medium within 30 min after addition of venom, and even after the onset of decline in twitch response. This contrasts with previous results with antivenom using the same experimental model, in which the window of time when antibodies are effective is shorter than 10 min. It is proposed that such differences may depend either on the higher affinity of the inhibitor for PLA2s or on the possibility that LY315920 reaches the cytosol of the nerve terminals, inhibiting neurotoxins that have been internalized. Our findings bear implications on the therapeutic potential of varespladib in neurotoxic snakebite envenomings mediated by presynaptically-acting PLA2s.
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Affiliation(s)
- Isadora Caruso Fontana Oliveira
- Post-Graduate Program in Pharmaceutical Sciences, University of Sorocaba (UNISO), Rodovia Raposo Tavares Km 92.5, 18023-000, Sorocaba, SP, Brazil
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Matthew R Lewin
- California Academy of Sciences, San Francisco, CA, 94118, USA; Ophirex, Inc., Corte Madera, CA, 94925, USA
| | - Yoko Oshima-Franco
- Post-Graduate Program in Pharmaceutical Sciences, University of Sorocaba (UNISO), Rodovia Raposo Tavares Km 92.5, 18023-000, Sorocaba, SP, Brazil.
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Xie C, Albulescu LO, Bittenbinder MA, Somsen GW, Vonk FJ, Casewell NR, Kool J. Neutralizing Effects of Small Molecule Inhibitors and Metal Chelators on Coagulopathic Viperinae Snake Venom Toxins. Biomedicines 2020; 8:E297. [PMID: 32825484 PMCID: PMC7555180 DOI: 10.3390/biomedicines8090297] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 12/27/2022] Open
Abstract
Animal-derived antivenoms are the only specific therapies currently available for the treatment of snake envenoming, but these products have a number of limitations associated with their efficacy, safety and affordability for use in tropical snakebite victims. Small molecule drugs and drug candidates are regarded as promising alternatives for filling the critical therapeutic gap between snake envenoming and effective treatment. In this study, by using an advanced analytical technique that combines chromatography, mass spectrometry and bioassaying, we investigated the effect of several small molecule inhibitors that target phospholipase A2 (varespladib) and snake venom metalloproteinase (marimastat, dimercaprol and DMPS) toxin families on inhibiting the activities of coagulopathic toxins found in Viperinae snake venoms. The venoms of Echis carinatus, Echis ocellatus, Daboia russelii and Bitis arietans, which are known for their potent haemotoxicities, were fractionated in high resolution onto 384-well plates using liquid chromatography followed by coagulopathic bioassaying of the obtained fractions. Bioassay activities were correlated to parallel recorded mass spectrometric and proteomics data to assign the venom toxins responsible for coagulopathic activity and assess which of these toxins could be neutralized by the inhibitors under investigation. Our results showed that the phospholipase A2-inhibitor varespladib neutralized the vast majority of anticoagulation activities found across all of the tested snake venoms. Of the snake venom metalloproteinase inhibitors, marimastat demonstrated impressive neutralization of the procoagulation activities detected in all of the tested venoms, whereas dimercaprol and DMPS could only partially neutralize these activities at the doses tested. Our results provide additional support for the concept that combinations of small molecules, particularly the combination of varespladib with marimastat, serve as a drug-repurposing opportunity to develop new broad-spectrum inhibitor-based therapies for snakebite envenoming.
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Affiliation(s)
- Chunfang Xie
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (L.-O.A.); (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Mátyás A. Bittenbinder
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands
| | - Govert W. Somsen
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Freek J. Vonk
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
| | - Nicholas R. Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK; (L.-O.A.); (N.R.C.)
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Jeroen Kool
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands; (C.X.); (M.A.B.); (G.W.S.); (F.J.V.)
- Centre for Analytical Sciences Amsterdam (CASA), 1098 XH Amsterdam, The Netherlands
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Diagnostic and Therapeutic Value of Aptamers in Envenomation Cases. Int J Mol Sci 2020; 21:ijms21103565. [PMID: 32443562 PMCID: PMC7278915 DOI: 10.3390/ijms21103565] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023] Open
Abstract
It is now more than a century since Albert Calmette from the Institut Pasteur changed the world of envenomation by demonstrating that antibodies raised against animal venoms have the ability to treat human victims of previously fatal bites or stings. Moreover, the research initiated at that time effectively launched the discipline of toxicology, first leading to the search for toxic venom components, followed by the demonstration of venoms that also contained compounds of therapeutic value. Interest from pharmaceutical companies to treat envenomation is, however, declining, mainly for economic reasons, and hence, the World Health Organization has reclassified this public health issue to be a highest priority concern. While the production, storage, and safety of antivenom sera suffer from major inconveniences, alternative chemical and technological approaches to the problem of envenomation need to be considered that bypass the use of antibodies for toxin neutralization. Herein, we review an emerging strategy that relies on the use of aptamers and discuss how close—or otherwise—we are to finding a viable alternative to the use of antibodies for the therapy of human envenomation.
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Albulescu LO, Hale MS, Ainsworth S, Alsolaiss J, Crittenden E, Calvete JJ, Evans C, Wilkinson MC, Harrison RA, Kool J, Casewell NR. Preclinical validation of a repurposed metal chelator as an early-intervention therapeutic for hemotoxic snakebite. Sci Transl Med 2020; 12:eaay8314. [PMID: 32376771 PMCID: PMC7116364 DOI: 10.1126/scitranslmed.aay8314] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 01/22/2020] [Accepted: 03/19/2020] [Indexed: 12/18/2022]
Abstract
Snakebite envenoming causes 138,000 deaths annually, and ~400,000 victims are left with permanent disabilities. Envenoming by saw-scaled vipers (Viperidae: Echis) leads to systemic hemorrhage and coagulopathy and represents a major cause of snakebite mortality and morbidity in Africa and Asia. The only specific treatment for snakebite, antivenom, has poor specificity and low affordability and must be administered in clinical settings because of its intravenous delivery and high rates of adverse reactions. This requirement results in major treatment delays in resource-poor regions and substantially affects patient outcomes after envenoming. Here, we investigated the value of metal ion chelators as prehospital therapeutics for snakebite. Among the tested chelators, dimercaprol (British anti-Lewisite) and its derivative 2,3-dimercapto-1-propanesulfonic acid (DMPS) were found to potently antagonize the activity of Zn2+-dependent snake venom metalloproteinases in vitro. Moreover, DMPS prolonged or conferred complete survival in murine preclinical models of envenoming against a variety of saw-scaled viper venoms. DMPS also considerably extended survival in a "challenge and treat" model, where drug administration was delayed after venom injection and the oral administration of this chelator provided partial protection against envenoming. Last, the potential clinical scenario of early oral DMPS therapy combined with a delayed, intravenous dose of conventional antivenom provided prolonged protection against the lethal effects of envenoming in vivo. Our findings demonstrate that the safe and affordable repurposed metal chelator DMPS can effectively neutralize saw-scaled viper venoms in vitro and in vivo and highlight the promise of this drug as an early, prehospital, therapeutic intervention for hemotoxic snakebite envenoming.
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Affiliation(s)
- Laura-Oana Albulescu
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Melissa S Hale
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Stuart Ainsworth
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Jaffer Alsolaiss
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Edouard Crittenden
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Juan J Calvete
- Laboratorio de Venómica Estructural y Funcional, Instituto de Biomedicina de Valencia, CSIC, Valencia 46010, Spain
| | - Chloe Evans
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Mark C Wilkinson
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Robert A Harrison
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
| | - Jeroen Kool
- Amsterdam Institute for Molecules Medicines and Systems, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081HV Amsterdam, Netherlands
| | - Nicholas R Casewell
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK.
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA Liverpool, UK
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Varespladib (LY315920) and Methyl Varespladib (LY333013) Abrogate or Delay Lethality Induced by Presynaptically Acting Neurotoxic Snake Venoms. Toxins (Basel) 2020; 12:toxins12020131. [PMID: 32093386 PMCID: PMC7076770 DOI: 10.3390/toxins12020131] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 11/21/2022] Open
Abstract
The phospholipase A2 (PLA2) inhibitor Varespladib (LY315920) and its orally bioavailable prodrug, methyl-Varespladib (LY333013) inhibit PLA2 activity of a wide variety of snake venoms. In this study, the ability of these two forms of Varespladib to halt or delay lethality of potent neurotoxic snake venoms was tested in a mouse model. The venoms of Notechis scutatus, Crotalus durissus terrificus, Bungarus multicinctus, and Oxyuranus scutellatus, all of which have potent presynaptically acting neurotoxic PLA2s of variable quaternary structure, were used to evaluate simple dosing regimens. A supralethal dose of each venom was injected subcutaneously in mice, followed by the bolus intravenous (LY315920) or oral (LY333013) administration of the inhibitors, immediately and at various time intervals after envenoming. Control mice receiving venom alone died within 3 h of envenoming. Mice injected with O. scutellatus venom and treated with LY315920 or LY333013 survived the 24 h observation period, whereas those receiving C. d. terrificus and B. multicinctus venoms survived at 3 h or 6 h with a single dose of either form of Varespladib, but not at 24 h. In contrast, mice receiving N. scutatus venom and then the inhibitors died within 3 h, similarly to the control animals injected with venom alone. LY315920 was able to reverse the severe paralytic manifestations in mice injected with venoms of O. scutellatus, B. multicinctus, and C. d. terrificus. Overall, results suggest that the two forms of Varespladib are effective in abrogating, or delaying, neurotoxic manifestations induced by some venoms whose neurotoxicity is mainly dependent on presynaptically acting PLA2s. LY315920 is able to reverse paralytic manifestations in severely envenomed mice, but further work is needed to understand the significance of species-specific differences in animal models as they compare to clinical syndromes in human and for potential use in veterinary medicine.
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Abstract
Snakebites are a hazard in the tropical world. Although antivenom therapy is effective, it is beset with inherent drawbacks. A better understanding of the major components of snake venoms and their neutralisation will help in improving snakebite treatment. Snake venom metalloproteinases (SVMPs) are responsible for severe haemorrhage, the inhibition of coagulation and platelet aggregation, observed in the victims of snakebite envenoming. Inhibitors from various sources including medicinal plants, animal venoms, and sera are sought to block the pharmacological functions of SVMPs. In this review, we describe the interaction of natural inhibitors with SVMPs. To understand their inhibitory mechanisms, we focussed on the complex structures of these inhibitors and SVMPs. There are three distinct classes of inhibitors; namely, chelators, competitive inhibitors, and non-competitive inhibitors. A small number of inhibitors show their anti-hemorrhagic activity in invivo animal models in treatment mode, but most studies evaluate either invitro neutralisation of enzymatic activity or invivo effects in pre-incubation protocols. We propose the distinct strategies and limitations to design either broad-spectrum or highly selective SVMP inhibitors. The goal of designing broad-spectrum inhibitors against SVMPs capable of effective treatment of snakebites without toxicity has been elusive, probably because of the narrow molecular footprint of inhibitors against a large number of SVMPs with distinct molecular surfaces. Our ability to design highly selective inhibitors is limited by the lack of information of interactions between selective inhibitors and SVMPs. Comparisons of structures of hemorrhagic and non-hemorrhagic SVMPs revealed different distributions of electric charge on the surface of SVMPs, which may be exploited to design specific inhibitors. The specific inhibitors may also be useful to identify target molecules of the SVMPs and help to understand their mechanism of action.
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Potential of Matrix Metalloproteinase Inhibitors for the Treatment of Local Tissue Damage Induced by a Type P-I Snake Venom Metalloproteinase. Toxins (Basel) 2019; 12:toxins12010008. [PMID: 31861940 PMCID: PMC7020480 DOI: 10.3390/toxins12010008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/07/2019] [Accepted: 12/12/2019] [Indexed: 12/16/2022] Open
Abstract
Snake bite envenoming is a public health problem that was recently included in the list of neglected tropical diseases of the World Health Organization. In the search of new therapies for the treatment of local tissue damage induced by snake venom metalloproteinases (SVMPs), we tested the inhibitory activity of peptidomimetic compounds designed as inhibitors of matrix metalloproteinases on the activities of the SVMP Batx-I, from Bothrops atrox venom. The evaluated compounds show great potential for the inhibition of Batx-I proteolytic, hemorrhagic and edema-forming activities, especially the compound CP471474, a peptidomimetic including a hydroxamate zinc binding group. Molecular dynamics simulations suggest that binding of this compound to the enzyme is mediated by the electrostatic interaction between the hydroxamate group and the zinc cofactor, as well as contacts, mainly hydrophobic, between the side chain of the compound and amino acids located in the substrate binding subsites S1 and S1′. These results show that CP471474 constitutes a promising compound for the development of co-adjuvants to neutralize local tissue damage induced by snake venom metalloproteinases.
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Knudsen C, Ledsgaard L, Dehli RI, Ahmadi S, Sørensen CV, Laustsen AH. Engineering and design considerations for next-generation snakebite antivenoms. Toxicon 2019; 167:67-75. [DOI: 10.1016/j.toxicon.2019.06.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 05/22/2019] [Accepted: 06/03/2019] [Indexed: 11/27/2022]
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Pucca MB, Cerni FA, Janke R, Bermúdez-Méndez E, Ledsgaard L, Barbosa JE, Laustsen AH. History of Envenoming Therapy and Current Perspectives. Front Immunol 2019; 10:1598. [PMID: 31354735 PMCID: PMC6635583 DOI: 10.3389/fimmu.2019.01598] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 06/26/2019] [Indexed: 01/15/2023] Open
Abstract
Each year, millions of humans fall victim to animal envenomings, which may either be deadly or cause permanent disability to the effected individuals. The Nobel Prize-winning discovery of serum therapy for the treatment of bacterial infections (tetanus and diphtheria) paved the way for the introduction of antivenom therapies for envenomings caused by venomous animals. These antivenoms are based on polyclonal antibodies derived from the plasma of hyperimmunized animals and remain the only specific treatment against animal envenomings. Following the initial development of serum therapy for snakebite envenoming by French scientists in 1894, other countries with high incidences of animal envenomings, including Brazil, Australia, South Africa, Costa Rica, and Mexico, started taking up antivenom production against local venomous animals over the course of the twentieth century. These undertakings revolutionized envenoming therapy and have saved innumerous patients worldwide during the last 100 years. This review describes in detail the above-mentioned historical events surrounding the discovery and the application of serum therapy for envenomings, as well as it provides an overview of important developments and scientific breakthroughs that were of importance for antibody-based therapies in general. This begins with discoveries concerning the characterization of antibodies, including the events leading up to the elucidation of the antibody structure. These discoveries further paved the way for other milestones in antibody-based therapies, such as the introduction of hybridoma technology in 1975. Hybridoma technology enabled the expression and isolation of monoclonal antibodies, which in turn formed the basis for the development of phage display technology and transgenic mice, which can be harnessed to directly obtain fully human monoclonal antibodies. These developments were driven by the ultimate goal of producing potent neutralizing monoclonal antibodies with optimal pharmacokinetic properties and low immunogenicity. This review then provides an outline of the most recent achievements in antivenom research, which include the application of new biotechnologies, the development of the first human monoclonal antibodies that can neutralize animal toxins, and efforts toward creating fully recombinant antivenoms. Lastly, future perspectives in the field of envenoming therapies are discussed, including rational engineering of antibody cross-reactivity and the use of oligoclonal antibody mixtures.
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Affiliation(s)
- Manuela B. Pucca
- Medical School, Federal University of Roraima, Boa Vista, Brazil
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Felipe A. Cerni
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
- Department of Biochemistry and Immunology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Rahel Janke
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | - Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - José E. Barbosa
- Department of Biochemistry and Immunology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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Williams HF, Layfield HJ, Vallance T, Patel K, Bicknell AB, Trim SA, Vaiyapuri S. The Urgent Need to Develop Novel Strategies for the Diagnosis and Treatment of Snakebites. Toxins (Basel) 2019; 11:E363. [PMID: 31226842 PMCID: PMC6628419 DOI: 10.3390/toxins11060363] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 01/09/2023] Open
Abstract
Snakebite envenoming (SBE) is a priority neglected tropical disease, which kills in excess of 100,000 people per year. Additionally, many millions of survivors also suffer through disabilities and long-term health consequences. The only treatment for SBE, antivenom, has a number of major associated problems, not least, adverse reactions and limited availability. This emphasises the necessity for urgent improvements to the management of this disease. Administration of antivenom is too frequently based on symptomatology, which results in wasting crucial time. The majority of SBE-affected regions rely on broad-spectrum polyvalent antivenoms that have a low content of case-specific efficacious immunoglobulins. Research into small molecular therapeutics such as varespladib/methyl-varespladib (PLA2 inhibitors) and batimastat/marimastat (metalloprotease inhibitors) suggest that such adjunctive treatments could be hugely beneficial to victims. Progress into toxin-specific monoclonal antibodies as well as alternative binding scaffolds such as aptamers hold much promise for future treatment strategies. SBE is not implicit during snakebite, due to venom metering. Thus, the delay between bite and symptom presentation is critical and when symptoms appear it may often already be too late to effectively treat SBE. The development of reliable diagnostical tools could therefore initiate a paradigm shift in the treatment of SBE. While the complete eradication of SBE is an impossibility, mitigation is in the pipeline, with new treatments and diagnostics rapidly emerging. Here we critically review the urgent necessity for the development of diagnostic tools and improved therapeutics to mitigate the deaths and disabilities caused by SBE.
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Affiliation(s)
| | | | - Thomas Vallance
- School of Pharmacy, University of Reading, Reading RG6 6AH, UK.
| | - Ketan Patel
- School of Biological Sciences, University of Reading, Reading RG6 6AH, UK.
| | - Andrew B Bicknell
- School of Biological Sciences, University of Reading, Reading RG6 6AH, UK.
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Ferraz CR, Arrahman A, Xie C, Casewell NR, Lewis RJ, Kool J, Cardoso FC. Multifunctional Toxins in Snake Venoms and Therapeutic Implications: From Pain to Hemorrhage and Necrosis. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00218] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Strategy for a globally coordinated response to a priority neglected tropical disease: Snakebite envenoming. PLoS Negl Trop Dis 2019; 13:e0007059. [PMID: 30789906 PMCID: PMC6383867 DOI: 10.1371/journal.pntd.0007059] [Citation(s) in RCA: 225] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Neutralizing properties of LY315920 toward snake venom group I and II myotoxic phospholipases A2. Toxicon 2019; 157:1-7. [DOI: 10.1016/j.toxicon.2018.11.292] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/25/2018] [Accepted: 11/09/2018] [Indexed: 12/22/2022]
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Kini RM, Sidhu SS, Laustsen AH. Biosynthetic Oligoclonal Antivenom (BOA) for Snakebite and Next-Generation Treatments for Snakebite Victims. Toxins (Basel) 2018; 10:toxins10120534. [PMID: 30551565 PMCID: PMC6315346 DOI: 10.3390/toxins10120534] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 11/16/2022] Open
Abstract
Snakebite envenoming is a neglected tropical disease that each year claims the lives of 80,000–140,000 victims worldwide. The only effective treatment against envenoming involves intravenous administration of antivenoms that comprise antibodies that have been isolated from the plasma of immunized animals, typically horses. The drawbacks of such conventional horse-derived antivenoms include their propensity for causing allergenic adverse reactions due to their heterologous and foreign nature, an inability to effectively neutralize toxins in distal tissue, a low content of toxin-neutralizing antibodies, and a complex manufacturing process that is dependent on husbandry and procurement of snake venoms. In recent years, an opportunity to develop a fundamentally novel type of antivenom has presented itself. By using modern antibody discovery strategies, such as phage display selection, and repurposing small molecule enzyme inhibitors, next-generation antivenoms that obviate the drawbacks of existing plasma-derived antivenoms could be developed. This article describes the conceptualization of a novel therapeutic development strategy for biosynthetic oligoclonal antivenom (BOA) for snakebites based on recombinantly expressed oligoclonal mixtures of human monoclonal antibodies, possibly combined with repurposed small molecule enzyme inhibitors.
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Affiliation(s)
- R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
| | - Sachdev S Sidhu
- Department of Molecular Genetics, The Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada.
| | - Andreas Hougaard Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
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Lewin MR, Gilliam LL, Gilliam J, Samuel SP, Bulfone TC, Bickler PE, Gutiérrez JM. Delayed LY333013 (Oral) and LY315920 (Intravenous) Reverse Severe Neurotoxicity and Rescue Juvenile Pigs from Lethal Doses of Micrurus fulvius (Eastern Coral Snake) Venom. Toxins (Basel) 2018; 10:E479. [PMID: 30453607 PMCID: PMC6265968 DOI: 10.3390/toxins10110479] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/14/2018] [Accepted: 11/14/2018] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE There is a clear, unmet need for effective, lightweight, shelf-stable and economical snakebite envenoming therapies that can be given rapidly after the time of a snake's bite and as adjuncts to antivenom therapies in the hospital setting. The sPLA2 inhibitor, LY315920, and its orally bioavailable prodrug, LY333013, demonstrate surprising efficacy and have the characteristics of an antidote with potential for both field and hospital use. METHODS The efficacy of the active pharmaceutical ingredient (LY315920) and its prodrug (LY333013) to treat experimental, lethal envenoming by Micrurus fulvius (Eastern coral snake) venom was tested using a porcine model. Inhibitors were administered by either intravenous or oral routes at different time intervals after venom injection. In some experiments, antivenom was also administered alone or in conjunction with LY333013. RESULTS 14 of 14 animals (100%) receiving either LY315920 (intravenous) and/or LY333013 (oral) survived to the 120 h endpoint despite, in some protocols, the presence of severe neurotoxic signs. The study drugs demonstrated the ability to treat, rescue, and re-rescue animals with advanced manifestations of envenoming. CONCLUSIONS Low molecular mass sPLA2 inhibitors were highly effective in preventing lethality following experimental envenoming by M. fulvius. These findings suggest the plausibility of a new therapeutic approach to snakebite envenoming, in this example, for the treatment of a coral snake species for which there are limitations in the availability of effective antivenom.
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Affiliation(s)
- Matthew R Lewin
- Ophirex, Inc., Corte Madera, CA 94925, USA.
- California Academy of Sciences, San Francisco, CA 94118, USA.
| | - Lyndi L Gilliam
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA.
| | - John Gilliam
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Stephen P Samuel
- California Academy of Sciences, San Francisco, CA 94118, USA.
- Queen Elizabeth Hospital, Kings Lynn, Norfolk PE30 4ET, UK.
| | - Tommaso C Bulfone
- Ophirex, Inc., Corte Madera, CA 94925, USA.
- California Academy of Sciences, San Francisco, CA 94118, USA.
| | - Philip E Bickler
- Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143, USA.
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501-2060, Costa Rica.
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Lewin MR, Gutiérrez JM, Samuel SP, Herrera M, Bryan-Quirós W, Lomonte B, Bickler PE, Bulfone TC, Williams DJ. Delayed Oral LY333013 Rescues Mice from Highly Neurotoxic, Lethal Doses of Papuan Taipan (Oxyuranus scutellatus) Venom. Toxins (Basel) 2018; 10:E380. [PMID: 30241297 PMCID: PMC6215158 DOI: 10.3390/toxins10100380] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/17/2018] [Accepted: 09/17/2018] [Indexed: 11/25/2022] Open
Abstract
There is an unmet need for economical snakebite therapies with long shelf lives that are effective even with delays in treatment. The orally bioavailable, heat-stable, secretory phospholipase A₂ (sPLA₂) inhibitor, LY333013, demonstrates antidotal characteristics for severe snakebite envenoming in both field and hospital use. A murine model of lethal envenoming by a Papuan taipan (Oxyuranus scutellatus) demonstrates that LY333013, even with delayed oral administration, improves the chances of survival. Furthermore, LY333013 improves the performance of antivenom even after it no longer reverses neurotoxic signs. Our study is the first demonstration that neurotoxicity from presynaptic venom sPLA2S can be treated successfully, even after the window of therapeutic antivenom has closed. These results suggest that sPLA₂ inhibitors have the potential to reduce death and disability and should be considered for the initial and adjunct treatment of snakebite envenoming. The scope and capacity of the sPLA2 inhibitors ability to achieve these endpoints requires further investigation and development efforts.
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Affiliation(s)
- Matthew R Lewin
- Ophirex, Inc., Corte Madera, CA 94925, USA.
- California Academy of Sciences, San Francisco, CA 94118, USA.
| | - José María Gutiérrez
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, an José 11501-2060, Costa Rica.
| | - Stephen P Samuel
- California Academy of Sciences, San Francisco, CA 94118, USA.
- Queen Elizabeth Hospital, Kings Lynn, Norfolk PE30 4ET, UK.
| | - María Herrera
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, an José 11501-2060, Costa Rica.
| | - Wendy Bryan-Quirós
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, an José 11501-2060, Costa Rica.
| | - Bruno Lomonte
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, an José 11501-2060, Costa Rica.
| | - Philip E Bickler
- Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, CA 94143, USA.
| | - Tommaso C Bulfone
- Ophirex, Inc., Corte Madera, CA 94925, USA.
- California Academy of Sciences, San Francisco, CA 94118, USA.
| | - David J Williams
- Department of Pharmacology and Therapeutics, Australian Venom Research Unit, University of Melbourne, Parkville, VIC 3010, Australia.
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Herzel BJ, Samuel SP, Bulfone TC, Raj CS, Lewin M, Kahn JG. Snakebite: An Exploratory Cost-Effectiveness Analysis of Adjunct Treatment Strategies. Am J Trop Med Hyg 2018; 99:404-412. [PMID: 29869597 PMCID: PMC6090346 DOI: 10.4269/ajtmh.17-0922] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 04/15/2018] [Indexed: 01/22/2023] Open
Abstract
The cost-effectiveness of the standard of care for snakebite treatment, antivenom, and supportive care has been established in various settings. In this study, based on data from South Indian private health-care providers, we address an additional question: "For what cost and effectiveness values would adding adjunct-based treatment strategies to the standard of care for venomous snakebites be cost-effective?" We modeled the cost and performance of potential interventions (e.g., pharmacologic or preventive) used adjunctively with antivenom and supportive care for the treatment of snakebite. Because these potential interventions are theoretical, we used a threshold cost-effectiveness approach to explore this forward-looking concept. We examined economic parameters at which these interventions could be cost-effective or even cost saving. A threshold analysis was used to examine the addition of new interventions to the standard of care. Incremental cost-effectiveness ratios were used to compare treatment strategies. One-way, scenario, and probabilistic sensitivity analyses were conducted to analyze parameter uncertainty and define cost and effectiveness thresholds. Our results suggest that even a 3% reduction in severe cases due to an adjunct strategy is likely to reduce the cost of overall treatment and have the greatest impact on cost-effectiveness. In this model, for example, an investment of $10 of intervention that reduces the incidence of severe cases by 3%, even without changing antivenom usage patterns, creates cost savings of $75 per individual. These findings illustrate the striking degree to which an adjunct intervention could improve patient outcomes and be cost-effective or even cost saving.
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Affiliation(s)
- Benjamin J. Herzel
- Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, San Francisco, California
- Loma Linda University School of Medicine, Loma Linda, California
| | - Stephen P. Samuel
- Queen Elizabeth Hospital, King’s Lynn, United Kingdom
- TCR Multispecialty Hospital, Krishnagiri, Tamil Nadu, India
| | - Tommaso C. Bulfone
- California Academy of Sciences, San Francisco, California
- Ophirex, Inc., Corte Madera, California
| | | | - Matthew Lewin
- California Academy of Sciences, San Francisco, California
- Ophirex, Inc., Corte Madera, California
| | - James G. Kahn
- Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, San Francisco, California
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Bulfone TC, Samuel SP, Bickler PE, Lewin MR. Developing Small Molecule Therapeutics for the Initial and Adjunctive Treatment of Snakebite. J Trop Med 2018; 2018:4320175. [PMID: 30154870 PMCID: PMC6091453 DOI: 10.1155/2018/4320175] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/03/2018] [Indexed: 01/19/2023] Open
Abstract
The World Health Organization (WHO) recently added snakebite envenoming to the priority list of Neglected Tropical Diseases (NTD). It is thought that ~75% of mortality following snakebite occurs outside the hospital setting, making the temporal gap between a bite and antivenom administration a major therapeutic challenge. Small molecule therapeutics (SMTs) have been proposed as potential prereferral treatments for snakebite to help address this gap. Herein, we discuss the characteristics, potential uses, and development of SMTs as potential treatments for snakebite envenomation. We focus on SMTs that are secretory phospholipase A2 (sPLA2) inhibitors with brief exploration of other potential drug targets on venom molecules.
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Affiliation(s)
- Tommaso C. Bulfone
- California Academy of Sciences, San Francisco, 94118 CA, USA
- Ophirex, Inc., Corte Madera, 94925 CA, USA
- University of California, San Francisco, 94118 CA, USA
| | - Stephen P. Samuel
- California Academy of Sciences, San Francisco, 94118 CA, USA
- General Medicine, Queen Elizabeth Hospital, King's Lynn, PE30 4ET, Norfolk, UK
| | | | - Matthew R. Lewin
- California Academy of Sciences, San Francisco, 94118 CA, USA
- Ophirex, Inc., Corte Madera, 94925 CA, USA
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Panda S, Kumari L. Anti-Ophidian Properties of Herbal Medicinal Plants: Could it be a Remedy for Snake Bite Envenomation? Curr Drug Discov Technol 2018; 16:319-329. [PMID: 30019647 DOI: 10.2174/1570163815666180718095655] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 07/10/2018] [Accepted: 07/11/2018] [Indexed: 01/09/2023]
Abstract
Snake bite envenoming causes high rates of morbidity and mortality and is one of the serious health-related concerns all over the globe. Around 3200 species of snakes have been discovered till date. Amid these species, about 1300 species of snakes are venomous. On account of its severity, World Health Organization (WHO) recently included snakebite envenoming in the list of neglected tropical diseases. Immunotherapy has partially solved the issues related to snakebite envenomation. However, it is associated with numerous adverse effects, due to which alternative treatment strategies are required for the treatment of snakebite. Traditionally, a large repository of herbal medicinal plants is known to possess activity against snake venom. An exploration of the therapeutic benefits of these medicinal plants used for the treatment of snakebites reveals the presence of various potential phytochemicals. The aim of the present review is to provide an outline regarding poisonous snakes all over the world, various compositions of snake venom, adverse effects related to anti-snake venom and numerous medicinal plants used for the anti-ophidian activity.
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Affiliation(s)
- Subhamay Panda
- Department of Pharmacy, Gupta College of Technological Sciences, Ashram More, Asansol-713301, India.,Indian Institute of Human and Social Sciences (IIHSS), Sitarampur, Asansol-713359, India
| | - Leena Kumari
- Department of Pharmaceutical Technology, Jadavpur University, Kolkata-700032, India
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Laustsen AH. Toxin-centric development approach for next-generation antivenoms. Toxicon 2018; 150:195-197. [PMID: 29857088 DOI: 10.1016/j.toxicon.2018.05.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 05/17/2018] [Accepted: 05/28/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark.
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50
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Ainsworth S, Slagboom J, Alomran N, Pla D, Alhamdi Y, King SI, Bolton FMS, Gutiérrez JM, Vonk FJ, Toh CH, Calvete JJ, Kool J, Harrison RA, Casewell NR. The paraspecific neutralisation of snake venom induced coagulopathy by antivenoms. Commun Biol 2018; 1:34. [PMID: 30271920 PMCID: PMC6123674 DOI: 10.1038/s42003-018-0039-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 03/26/2018] [Indexed: 01/19/2023] Open
Abstract
Snake envenoming causes several potentially lethal pathologies. The specific pathology is dictated by the toxin composition of venom, which varies by species, geography and ontogeny. This variation severely restricts the paraspecific efficacy of antivenoms used to treat snakebite victims. With a view to devising pathology-specific snakebite treatments, we assessed the procoagulant activity of 57 snake venoms and investigated the efficacy of various antivenoms. We find that procoagulant venoms act differentially on key steps of the coagulation cascade, and that certain monospecific antivenoms work in a previously unrecognised paraspecific manner to neutralise this activity, despite conventional assumptions of congener-restricted efficacy. Moreover, we demonstrate that the metal chelator EDTA is also capable of neutralising venom-induced lethality in vivo. This study illustrates the exciting potential of developing new, broad-spectrum, toxin-targeting antivenoms capable of treating key snakebite pathologies, and advocates a thorough re-examination of enzyme inhibiting compounds as alternative therapies for treating snakebite victims.
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Affiliation(s)
- Stuart Ainsworth
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Julien Slagboom
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, 1081 LA, The Netherlands
| | - Nessrin Alomran
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Davinia Pla
- Laboratorio de Venómica Estructural y Funcional, Instituto de Biomedicina de Valencia, CSIC, Valencia, 46010, Spain
| | - Yasir Alhamdi
- Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE, UK
| | - Sarah I King
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Fiona M S Bolton
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Freek J Vonk
- Naturalis Biodiversity Center, 2333 CR, Leiden, The Netherlands
| | - Cheng-Hock Toh
- Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE, UK
- Roald Dahl Haemostasis and Thrombosis Centre, Royal Liverpool University Hospital, Liverpool, L7 8XP, UK
| | - Juan J Calvete
- Laboratorio de Venómica Estructural y Funcional, Instituto de Biomedicina de Valencia, CSIC, Valencia, 46010, Spain
| | - Jeroen Kool
- Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, 1081 LA, The Netherlands
| | - Robert A Harrison
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Nicholas R Casewell
- Alistair Reid Venom Research Unit, Parasitology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
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