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Bebal FF, Bagwe AD, D’Souza RC, Sharma BB. Identifying toxic effects and metabolic perturbations of Duttaphrynus melanostictus skin extracts in human erythrocytes. Toxicol Res (Camb) 2024; 13:tfae086. [PMID: 38835821 PMCID: PMC11145735 DOI: 10.1093/toxres/tfae086] [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: 03/28/2024] [Revised: 05/13/2024] [Accepted: 05/28/2024] [Indexed: 06/06/2024] Open
Abstract
Background Skin secretions of toads are widely used in medicine all over the world for their antiviral, anti-infective, and cardiotonic properties. Because these secretions are mostly employed to combat blood parasite infection, it is important to understand their potential toxic effects on human erythrocytes. Therefore, the objective of the current investigation was to elucidate the effects of Duttaphrynus melanostictus (Schneider) skin extracts on the physiology of human erythrocytes. Methods Toads captured from their natural habitat were separated into three groups according to their body size. Hydroalcoholic extracts of toad skin were prepared by reflux heating. These extracts were then evaluated for their hemolytic and hemoglobin denaturation potential. The effects of the extracts on cytosolic and membrane-bound enzymes of human erythrocytes were assessed. Results The hemolysis and hemoglobin denaturation caused by these extracts correlated positively with the respective toad sizes. Extracts from medium and large toads led to increased osmotic fragility even at near iso-osmotic concentrations. Biochemical analysis of hemolysate showed that the treatment induced a shift of metabolic flux toward the glutathione pathway. Analysis of membrane-bound enzymes revealed a significant decrease in the activity of Na+/K+ ATPase and acetylcholinesterase. SDS-PAGE analysis of the erythrocyte membrane did not show the band of tropomodulin for the cells treated with 1000 𝜇g/ml extract from large toads. Conclusions In conclusion, the present study demonstrates that the toxicity of toad skin secretions aggravates with the size of the animal and interferes with the physiology of human erythrocytes, leading to their membrane disruption and rapid lysis.
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Affiliation(s)
- Fatima F Bebal
- Department of Zoology, KET’s V. G. Vaze College of Arts, Science & Commerce (Autonomous), Mithagar Road, Mumbai - 400 081, Maharashtra, India
| | - Akshay D Bagwe
- Department of Zoology, KET’s V. G. Vaze College of Arts, Science & Commerce (Autonomous), Mithagar Road, Mumbai - 400 081, Maharashtra, India
- Department of Zoology, Sophia College for Women (Autonomous), Bhulabhai Desai Road, Mumbai - 400 026, Maharashtra, India
| | - Roshan C D’Souza
- Department of Zoology, Sophia College for Women (Autonomous), Bhulabhai Desai Road, Mumbai - 400 026, Maharashtra, India
| | - Bharatbhushan B Sharma
- Department of Zoology, KET’s V. G. Vaze College of Arts, Science & Commerce (Autonomous), Mithagar Road, Mumbai - 400 081, Maharashtra, India
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He D, Hu S, Huang Z, Mo C, Cheng X, Song P, Li Y, Song T, Guan Z, Zhou Y, Zhang X, Liao M. Metabolomics analyses of serum metabolites perturbations associated with Naja atra bite. PLoS Negl Trop Dis 2023; 17:e0011507. [PMID: 37639406 PMCID: PMC10461852 DOI: 10.1371/journal.pntd.0011507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 07/06/2023] [Indexed: 08/31/2023] Open
Abstract
Naja atra bite is one of the most common severe snakebites in emergency departments. Unfortunately, the pathophysiological changes caused by Naja atra bite are unclear due to the lack of good animal models. In this study, an animal model of Naja atra bite in Guangxi Bama miniature pigs was established by intramuscular injection at 2 mg/kg of Naja atra venom, and serum metabolites were systematically analyzed using untargeted metabolomic and targeted metabolomic approaches. Untargeted metabolomic analysis revealed that 5045 chromatographic peaks were obtained in ESI+ and 3871 chromatographic peaks were obtained in ESI-. Screening in ESI+ modes and ESI- modes identified 22 and 36 differential metabolites compared to controls. The presence of 8 core metabolites of glutamine, arginine, proline, leucine, phenylalanine, inosine, thymidine and hippuric acid in the process of Naja atra bite was verified by targeted metabolomics significant difference (P<0.05). At the same time, during the verification process of the serum clinical samples with Naja atra bite, we found that the contents of three metabolites of proline, phenylalanine and inosine in the serum of the patients were significantly different from those of the normal human serum (P<0.05). By conducting functional analysis of core and metabolic pathway analysis, we revealed a potential correlation between changes in key metabolites after the Naja atra bite and the resulting pathophysiological alterations, and our research aims to establish a theoretical foundation for the prompt diagnosis and treatment of Naja atra bite.
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Affiliation(s)
- Dongling He
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Shaocong Hu
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Zhi Huang
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Caifeng Mo
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Xiaoyang Cheng
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Pengshu Song
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Yalan Li
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Tianlin Song
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Zhezhe Guan
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Yi Zhou
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Xuerong Zhang
- Life Science Institute Guangxi Medical University, Nanning, PR China
| | - Ming Liao
- Life Science Institute Guangxi Medical University, Nanning, PR China
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Esmaeilishirazifard E, Usher L, Trim C, Denise H, Sangal V, Tyson GH, Barlow A, Redway KF, Taylor JD, Kremyda-Vlachou M, Davies S, Loftus TD, Lock MMG, Wright K, Dalby A, Snyder LAS, Wuster W, Trim S, Moschos SA. Bacterial Adaptation to Venom in Snakes and Arachnida. Microbiol Spectr 2022; 10:e0240821. [PMID: 35604233 PMCID: PMC9248900 DOI: 10.1128/spectrum.02408-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/14/2022] [Indexed: 11/20/2022] Open
Abstract
Animal venoms are considered sterile sources of antimicrobial compounds with strong membrane-disrupting activity against multidrug-resistant bacteria. However, venomous bite wound infections are common in developing nations. Investigating the envenomation organ and venom microbiota of five snake and two spider species, we observed venom community structures that depend on the host venomous animal species and evidenced recovery of viable microorganisms from black-necked spitting cobra (Naja nigricollis) and Indian ornamental tarantula (Poecilotheria regalis) venoms. Among the bacterial isolates recovered from N. nigricollis, we identified two venom-resistant, novel sequence types of Enterococcus faecalis whose genomes feature 16 virulence genes, indicating infectious potential, and 45 additional genes, nearly half of which improve bacterial membrane integrity. Our findings challenge the dogma of venom sterility and indicate an increased primary infection risk in the clinical management of venomous animal bite wounds. IMPORTANCE Notwithstanding their 3 to 5% mortality, the 2.7 million envenomation-related injuries occurring annually-predominantly across Africa, Asia, and Latin America-are also major causes of morbidity. Venom toxin-damaged tissue will develop infections in some 75% of envenomation victims, with E. faecalis being a common culprit of disease; however, such infections are generally considered to be independent of envenomation. Here, we provide evidence on venom microbiota across snakes and arachnida and report on the convergent evolution mechanisms that can facilitate adaptation to black-necked cobra venom in two independent E. faecalis strains, easily misidentified by biochemical diagnostics. Therefore, since inoculation with viable and virulence gene-harboring bacteria can occur during envenomation, acute infection risk management following envenomation is warranted, particularly for immunocompromised and malnourished victims in resource-limited settings. These results shed light on how bacteria evolve for survival in one of the most extreme environments on Earth and how venomous bites must be also treated for infections.
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Affiliation(s)
- Elham Esmaeilishirazifard
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Louise Usher
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Carol Trim
- School of Psychology and Life Sciences, Faculty of Science, Engineering and Social Sciences, Canterbury Christ Church University, Canterbury, Kent, United Kingdom
| | - Hubert Denise
- EMBL-EBI European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Vartul Sangal
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
| | - Gregory H. Tyson
- Food and Drug Administration, Center for Veterinary Medicine, Office of Research, Laurel, Maryland, USA
| | - Axel Barlow
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Keith F. Redway
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - John D. Taylor
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- School of Environment and Life Sciences, University of Salford, Salford, Greater Manchester, United Kingdom
| | - Myrto Kremyda-Vlachou
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Sam Davies
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
| | | | | | - Kstir Wright
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Andrew Dalby
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Lori A. S. Snyder
- School of Life Sciences, Pharmacy, and Chemistry, Kingston University, London, United Kingdom
| | - Wolfgang Wuster
- Molecular Ecology and Evolution at Bangor, School of Biological Sciences, College of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
| | - Steve Trim
- Venomtech, Ltd., Sandwich, Kent, United Kingdom
| | - Sterghios A. Moschos
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
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Ajisebiola BS, Adeniji OB, James AS, Ajayi BO, Adeyi AO. Naja nigricollis venom influenced reproductive and neurological functions via modulation of pro-inflammatory cytokines and oxidative damage in male rats. Metabol Open 2022; 14:100188. [PMID: 35633732 PMCID: PMC9130106 DOI: 10.1016/j.metop.2022.100188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 04/30/2022] [Accepted: 05/12/2022] [Indexed: 01/03/2023] Open
Abstract
Reproductive and neurological anomalies are often characterized by malfunctioning of reproductive and nervous organs sometimes attributed to systemic toxins. However, limited information is available on the impact of snake venom toxins on male reproductive and nervous system. This study investigated the toxicological effects of Naja nigricollis venom on male reproductive and neural functions in rat model. Twenty male Wistar rats weighing between 195 and 230 g were divided randomly into two groups of ten rats each. Group 1 served as normal control while rats in group 2 were envenomed with a single intraperitoneal injection of 0.25 mg/kg−1 (LD12.5) of N. nigricollis venom on first and twenty fifth day within the period of fifty days experiment. The venom significantly decreased sperm counts, motile cells and volume combined with increased sperm abnormalities. The venom induced hormonal imbalances in the envenomed group as levels of testosterone, luteinizing and follicle stimulating hormones depreciated compared to the control. Oxidative stress biomarkers: malondialdehyde significantly increased parallels with depletion of glutathione level and catalase activities in testis, epididymis and brain of envenomed rats. Furthermore, N. nigricollis venom up-regulated tumor necrosis factor-alpha (TNF-α) and interleukin1-beta (IL-1β) production in testis, epididymis and brain of envenomed rats compared to the control. Also, various histological alterations were noticed in tissues of testis, epididymis and brain of envenomed rats. Findings indicated that N. nigricollis venom is capable of inducing reproductive and neurological dysfunction in envenomed victims.
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Affiliation(s)
| | | | - Adewale Segun James
- Department of Chemical Sciences (Biochemistry Program), Augustine University, Lagos, Nigeria
| | - Babajide O. Ajayi
- Onco-preventives and Systems Oncology Research Laboratory, Biochemistry Unit, Department of Chemical Sciences, Ajayi Crowther University, Oyo, Nigeria
| | - Akindele Oluwatosin Adeyi
- Animal Physiology Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
- Corresponding author.
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Profiling the Murine Acute Phase and Inflammatory Responses to African Snake Venom: An Approach to Inform Acute Snakebite Pathology. Toxins (Basel) 2022; 14:toxins14040229. [PMID: 35448838 PMCID: PMC9028489 DOI: 10.3390/toxins14040229] [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: 02/01/2022] [Revised: 03/03/2022] [Accepted: 03/15/2022] [Indexed: 11/17/2022] Open
Abstract
Snake envenoming causes rapid systemic and local effects that often result in fatal or long-term disability outcomes. It seems likely that acute phase and inflammatory responses contribute to these haemorrhagic, coagulopathic, neurotoxic, nephrotoxic and local tissue destructive pathologies. However, the contributory role of acute phase/inflammatory responses to envenoming is under-researched and poorly understood—particularly for envenoming by sub-Saharan African venomous snakes. To provide data to help guide future studies of human patients, and to explore the rationale for adjunct anti-inflammatory medication, here we used an in vivo murine model to systematically assess acute phase and inflammatory responses of mice to ten African snake venoms. In addition to investigating snake species-specific effects of venom on the cardiovascular system and other key organs and tissues, we examined the response to intravascular envenoming by acute phase reactants, including serum amyloid A, P-selectin and haptoglobin, and several cytokines. Venoms of the spitting (Naja nigricollis) and forest (N. melanoleuca) cobras resulted in higher acute phase and inflammatory responses than venoms from the other cobras, mambas and vipers tested. Naja nigricollis venom also stimulated a 100-fold increase in systemic interleukin 6. Thin blood films from venom-treated mice revealed species-specific changes in red blood cell morphology, indicative of membrane abnormalities and functional damage, lymphopenia and neutrophil leukocytosis. Our ex vivo assays with healthy human blood treated with these venoms identified that N. nigricollis venom induced marked levels of haemolysis and platelet aggregation. We conclude that African snake venoms stimulate very diverse responses in this mouse model of acute systemic envenoming, and that venoms of the African cobras N. nigricollis and N. melanoleuca, in particular, cause marked inflammatory and non-specific acute phase responses. We also report that several African snake venoms cause haemolytic changes. These findings emphasise the importance of understanding acute responses to envenoming, and that further research in this area may facilitate new diagnostic and treatment approaches, which in turn may lead to better clinical outcomes for snakebite patients.
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Okafor AI, Ogban NN, Odinigwe AA. Kolaviron alleviates haematological abnormalities and hepato-renal damage in Naja nigricollis nigricollis venom-treated rats. Toxicol Rep 2022; 9:1869-1876. [DOI: 10.1016/j.toxrep.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/29/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
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Effects of 3FTx Protein Fraction from Naja ashei Venom on the Model and Native Membranes: Recognition and Implications for the Mechanisms of Toxicity. Molecules 2021; 26:molecules26082164. [PMID: 33918763 PMCID: PMC8070352 DOI: 10.3390/molecules26082164] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/27/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Three-finger toxins are naturally occurring proteins in Elapidae snake venoms. Nowadays, they are gaining popularity because of their therapeutic potential. On the other hand, these proteins may cause undesirable reactions inside the body′s cells. A full assessment of the safety of Naja ashei venom components for human cell application is still unknown. The aim of the study was to determine the effect of the exogenous application of three-finger toxins on the cells of monocytes (U-937) and promyelocytes (HL-60), with particular emphasis on the modification of their membranes under the influence of various doses of 3FTx protein fraction (0–120 ng/mL). The fraction exhibiting the highest proportion of 3FTx proteins after size exclusion chromatography (SEC) separation was used in the experiments. The structural response of cell membranes was described on the basis of single-component and multi-component Langmuir monolayers that mimicked the native membranes. The results show that the mechanism of protein–lipid interactions depends on both the presence of lipid polar parts (especially zwitterionic type of lipids) and the degree of membrane saturation (the greatest-for unsaturated lipids). The biochemical indicators reflecting the tested cells (MDA, LDH, cell survival, induction of inflammation, LD50) proved the results that were obtained for the model.
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Imam TS, Tukur Z, Bala AA, Ahmad NB, Ugya AY. In vitro trichomonocidal potency of Naja nigricollis and Bitis arietans snake venom. INTERNATIONAL JOURNAL OF ONE HEALTH 2021. [DOI: 10.14202/ijoh.2021.6-11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: Trichomonas vaginalis drug's limited efficacy and high toxicity, justify the need to explore other therapeutic agents, including animal toxins. In this study, the Naja nigricollis and Bitis arietans snake venoms were used to assess such trichomonocidal effect.
Materials and Methods: The median lethal dose (LD50) value for both snake species was calculated by probit analysis using a statistical package for the sciences version 20.0 with an LD50 of 4.04 μg/mL for the N. nigricollis, and no mortality was observed in the B. arietans envenomed rats.
Results: The trichomonocidal potency of the snake venom on T. vaginalis was evident with a growth inhibitory concentration of 89% with a half-maximal inhibitory concentration (IC50) of 0.805 μg/mL in B. arietans while 95% for N. nigricollis at an IC50 of 0.411 μg/mL.
Conclusion: The statistical analysis of one-way analysis of variance shows a significant difference (p<0.05) between the venoms and positive control group (p<0.001), and there is no significant difference between each venom and its varying concentration (p>0.05). As the least concentration can be useful, interestingly, there is no significant difference in the efficacy of N. nigricollis and B. arietans to T. vaginalis (p>0.05); as such, either of the venom can be used for the treatment of trichomoniasis.
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Affiliation(s)
- Tijjani Sabiu Imam
- Department of Biological Sciences, Bayero University Kano, Kano, Nigeria
| | - Zainab Tukur
- Department of Biological Sciences, Bayero University Kano, Kano, Nigeria
| | | | | | - Adamu Yunusa Ugya
- Key Lab of Groundwater Resources and Environment of Ministry of Education, Key Lab of Water Resources and Aquatic Environment of Jilin Province, College of New Energy and Environment, Jilin University, Changchun, China; Department of Environmental Management, Kaduna State University, Kaduna, Nigeria
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Okafor AI, Onyike E. Inhibition of key enzymes linked to snake venom induced local tissue damage by kolaviron. J Basic Clin Physiol Pharmacol 2020; 32:1121-1130. [PMID: 34898137 DOI: 10.1515/jbcpp-2020-0176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/30/2020] [Indexed: 06/14/2023]
Abstract
OBJECTIVES Snakebite envenoming is an important public health problem that threatens the lives of healthy individuals especially in many tropical countries like Nigeria. Antivenins, the only efficient approach for snakebite envenoming, are limited in their efficacy in the neutralization of local tissue damage. Snake venom phospholipase A2 (PLA2), protease, hyaluronidase and l-amino acid oxidase (LAAO) are the major hydrolytic enzymes involve in local tissue damage. Therefore, this study evaluates the inhibitory effect of kolaviron (KV) against Naja n. nigricollis (NNN) snake venom hydrolytic enzymes involved in local tissue damage. METHODS Kolaviron was evaluated for its ability to inhibit the hydrolytic enzyme activities of NNN venom phospholipase A2 (PLA2), protease, hyaluronidase and l-amino acid oxidase (LAAO). Present study also deals with the neutralization of NNN venom enzyme(s) induced complications such as myotoxic, edemic, hemolytic and procoagulant effects. RESULTS Kolaviron inhibited the PLA2, protease, hyaluronidase and LAAO enzyme activities of NNN venom in a dose-dependent manner. Furthermore, myotoxic, edemic, hemolytic and procoagulant effects induced by NNN venom enzyme were neutralized significantly (p<0.05) when different doses of KV were pre-incubated with venom before assays. CONCLUSIONS These findings clearly present kolaviron as a potent inhibitor against NNN venom hydrolytic enzymes involved in local tissue damage and may act by either forming an inhibitor-enzyme complex that restricts the substrate availability to the enzyme or direct binding to the enzyme active site that affects the enzyme activity thereby mitigating venom-induced toxicity.
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Affiliation(s)
| | - Elewechi Onyike
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria
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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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